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MICROSCOPICAL MORPHOLOGY.

Digitized by tine Internet Arciiive

in 2010 witii funding from
Columbia University Libraries

http://www.archive.org/details/microscopicalmorOOheit

Ml( 1{()S( ()1>1( AL MOniMIOLOCwV

ANIMAL 1U)T)Y

IX HExVLTII AM) DISEASE.

C. HEITZMANX, M.D.

Late Lecturer on Morbid Anatomy at tiii: ITmvkksitv in Vienna, Austria.

WITH 380 ORIGINAL ENGRAVINGS.

I

NEW-YORK:

J. H. VAIL & COMPANY, 21 ASTOR PLACE.

1883.

Copyright, 1882, by C. Heitzmann, M. D.

Pri^Bs of Francis Haht & Co.
New-York.

IMJEFACE.

"I^N presenting: tliis book, the result of ten years' intense labor, to the
-^ pnblie, I am aware that not all the facts and conclusions here laid
doAvn will meet the immediate approval of professional microseopists.

The cell-theory, which for more than thirty years held sway over the
minds of scientists, was contradicted by me in 1873, when I demonstrated
the continiuty of all elements engaged in the construction of tissues. In
1872, I discovered the coiniections between cartilage-corpuscles, which,
thanks to a simplitied method, are now easily seen. Shortly afterward,
the intimate structure of "protoplasm" was discovered, and it was found
that the same structure is pi'esent throughout all the interstitial sub-
stances which had hitherto been considered lifeless.

As many of the assertions made in 1872 and 1873 have already been
found correct by good observers, I confidently expect that the others
too will, in time, be accepted, although directly contrary to the cell-
theory.

In the autumn of 187'4 I left Vienna, and, on the first of November
of the same year, opened a laboratory for microscopical investigation in
New-York. This has proved successful beyond all expectation. Over
seven hundi-ed attendants, among them some of the most intellectual
and independent members of the medical profession, have here satisfied
themselves of the correctness of my assertions. A number of these have
made valuable investigations in my laboratory, the results of which will
be fovmd embodied in various articles in this book.

In view of these facts, I can await patiently the approval of scientists
abroad. A doctrine which is accepted by good observers in America
cannot be lost, but Avill develop independently of Em'opean microseop-
ists, who, to a great extent, are prejudiced by the teachings of the older
mastei's.

Again have facts made it evident that the United States of America
are ahead whenever new ideas of practical importance are to be acknowl-
edged. I have received, in New- York, much encom-agement from my
students and co-workers. I have also been magnanimously supported by
a fi'iend, who is not a medical man, but a prince in character and wealth,
and who siu'passes most Em-opean princes in that he will not allow me to
inscribe his name upon the dedicatory page.

The illustrations of this book are, without exception, my own draw-
ings, and have been transferred on metal to my complete satisfaction by
the Moss Engraving Company, of this city.

C. Heitzmaxx.

39 West 45tii Ptukkt. Nkw-York, August, 1882.

CONTEXTS.

1'a<;k.

I. Methods 1

Infusion '2 Cutting 6

Moist chinnber 3 Mounting 7

Hcdialilc stage 3 Staining 9

Elvvlriritii i Injections 10

rrejMiration of fre^h tissues. . . i How to vorlc u-itli the microsrope 10

Preservation of tissues 5

II. Gexekal Properties of Living Matter 13

Cheni istnj 13 Generation 15

Manifestation of life 14 Historical sketch of the study of tiring

Projjerties of living matter 14 matter 18

III. The Arra^'gemext op the Living Matter in "Protoplasm".. 21

Ama'bas 21 Colorless blood-corpuscles of man 26

lilood-corpHscles of the craw- Colostrum corpnscles 28

•"■'•''' "-3 Conclusions 28

Blood of the neict 25

Analysis of the assertions made in 1873 30

Only a part of " protoplasm" is Analysis of contraction and extension, 34

living matter 33 Analysis of tetanus 35

Chemical re-agents 33 Analysis of investing layers 35

Analysis of rest 34 Analysis of vacuoles 36

Comparison of amoeba and man 36

The Structure of the Blood-corpuscles of the Oyster. By A. M.

Hurlbutt 37

The Structure and Growth of Some Forms of Mildew. By William

Hassloch 40

IV. The Phases of Development of Living Matter 46

Amecba- 46 Corpusclesof the medulla of bone 50

Cartilage-corpuscles 47 Conclusions. . .51

Bone-corpuscles 50

The cell-theory in the light of these researches 53

Structure of plants 57 Xomenclaturc 57

The general constitution of the body, as recognized by single

plastids 58

V. The Structure and Origin of Colored Blood-corpuscles... 64

The Structure of Colored Blood-corpuscles. By Louis Elsberg 64

Observations 64 Conclusions 94

History 73

\-iii CONTENTS.

I'AOE.

The origin of colored blood-corpuscles 98

Formation of blood from carti- Formation of bloftd in inflamed hone.. 100

luge 98

Formation of Blood in Cartilage and Bone of Birds. By L. Sehoney. 103
Experimental and Mieroscoi)ieal Studies on the Origin of the Blood-
globules. By A. W. Johnstone 105

VI. Tissues ix General Ill

Origin Ill

Definition 114

Division 114

1. Connective tissue 114 3. Xerve-tisstie 115

2. ilnscle-t issue 115 i. Epithelial tissue 115

The relation of living matter to the interstitial substance 115

Life of cartilage-corpuscles 116 Blood-ressels 127

Medullary tissue 117 JHuscle-l issue 127

Tissue of the umbilical cord — 120 .Struct u)-e-elemenfs of the nervous system 128

Tissue of tendon 122 Epithelial tissue 130

Tissue of periosteum 1-24 Conclusions 131

Tissue of bone 126 Is blood a tissue ? 134

Researches and deductions since 1S73 . 135

VII. CoxxECTivE Tissue 143

Definition and division 143

1. Myxomatous or mucoid tissue 146

fa) Medullary tissue 147 fc) Myxomatous tissue of the umbilical

(b) Reticular tissue 147 cord 150

Fat-tissue 155

2. Striated or fibrous connective tissue 158

fa) Delicate connective tissue dies running in a longittidinal

composed of fibrillm or of direction 164

comparatively thi7i bundles (d) Dense connective tissue composed

of flbrilla; 159 of interlacing ribbons 168

(b) Dense connective tissue (e) Coalesced layers of elastic basis-
composed of coarse, interlae- substance, arranged in a sheath-
ing bundles 162 like manner 168

(c) Dense connective tissue (f) Lamellated layers of fibrous inter-
composed of coarse bun- lacing connective tissue 169

Researches on the Microscopical Struetiue of the Cornea. By

William Hassloeh 171

Development of fibrous connective tissue 179

Secretion theory 181 Territories 182

Transformation theory 181 Bioplasson theory 182

Elastic substance 182

3. Cartilage-tissue 185

History. By Louis Elsberg 185

Varieties of eartUage tissue 190

fa) Reticular or elastic cartilage 191 fc) Hyaline cartilage 195

fb) Striated or fibrous cartilage 193

The structure of hyaline cartilage 198

The Structure of the Th\Toid Cartilage. By Louis Elsberg 206

Development of cartilage 212

COXTh'XTS. ix

I ■ \ ' . i; .

4. Bone-tissue j 1 ^

Ilislori/ "jiK iiiiiif-i-'irjiiisitis jji

Mrtliixls 22"

Varieties of l>one-tissue 'J'Jli

(a) ('aiiri'lloiis, rpi/i/ii/sedl, or rcriostrimi ". 228

s/joiij/!/ boiH'-lissiie 223 IU<»ul-Femtrln 230

(b) Corliriil or roiiijnirt bone- Mcdiillii of bone 230

tissue 225

The relation of the systems of lamelhv to the l)loo<l-vessels 'J'A]

Development of bone 23G

(A) Derelopmeut of bone from (c) Forninlion of red blood-corpuscles
cartilayc 238 and blood-ressels 243

(a) CalrificafioH 238 (d) Formation of bone from medulla.. 2-17

(b) Formation of mcduUanj tis-
sue 242

The Process of Ossilicatiou in Birds. By A. L. Sehoney 251

(B) Development of bone from (C) The grou-th and retrogression of
yibrous connective tissue. .. . 254 bone 258

VIII. Muscle-tissue 262

1 . Smooth or unstriped muscle 263

2. Striped muscle 265

The Structure of the Muscle of the Lobster. By M, L. Holbrook. . 274

IX. Nerve-tissue 270

1. Nerve-centers 280

(A) Brain 280 (E) The connective tissue investments

The origin of the cerebral of the brain and the spinal cord .. . 292

nerves 282 Dura mater 292

(B) Gray substance 283 Arachnoidea 293

(C) Ganglionic elements 285 Pia mater 293

(D) White substance of the (F) The ganglia 293

spinal cord 290

2. Nerves 29-i

(a) ilcdullatcd nerves 295 (b) \on-medullated nerves 298

3. Terminations of nerves 298

(a) Termination of meduUatcd (b) Termination of non-medullated

nerve-fibers 299 nerve-fibers 300

Development of nervous tissue 302

Methods for the preparation of nerve-tissue 303

Analysis of bioplasson in its relations to nerve-action 305

X. Epithelial and Endothelial Tissue 311

Definition : 311

Peritoneum 315 Crystalline lens 316

Division 318

Single epithelial layers 321 Stratified epithelial layers 322

Termination of nerves 323

Glands 325

Performances of epithelium 327

fa) Watery secretion 328 (c) Fatty secretion 332

(bj Mucous secretion 329

X COXTEXTS.

I'AGK.

The vascular system. . . . 333

1 . The heart 333

2. The arteries 335

3. The veins 337

■i. The capillaries 339

Derelopment of eapiUaries 341

The Ij-mphatic system 343

Lymph -vessels 343 Thyrokl body 348

Lymph -yanylia and lymph - Siipra-rcttal capsule 349

tissue 345 Spleen . . 350

Thym us body 348

XI. Inflammation 353

Historical sketch 353

1. Inflammation of connective tissue 356

(A) Inflammation of the perios- Injuries at the lateral portions of the
teum' 356 articular cartilage 363

Inflammation of the tendon — 360 Feeding of cartilage-corpuscles icith in-

(B) Inflammation of cartilage. 361 soluble granular substances 364

Superflcial injuries in the mid- (C) Inflammation of bone 367

die of the condyle 361 A'eir formation of blood-ressels in in-

Sitn ultaneous injuries of the flamed bone-tissue 373

articular cartilage and the Conclusions arriretl at in 1873 376

subjacent epiphyseal bone.. 362

The healing process of fractured bones . 381

Necrosis. By C. F. W. Biidecker 390

Rachitis and osteomalacia 393

Rachitis. liiekets 395 Osteomalacia. 399

2. Inflammation of muscle. Trichinosis 401

3. Inflammation of nerve-tissue 407

Microscopical Studies on Abscess of the Brain. By H. G. Beyer. . 407

(a) Wall of abscess 410 (d) Xon-medullated nerre-flbers 414

(b) W7iite substance 412 (dj Gray substance 414

4. Inflammation of epithelia and endothelia 418

Varieties of inflammation 422

(a) Catarrhal inflammation . . . 423 (e) Suppurative inflammation 424

(b) Croitpous inflammation.. . 423 Healing process of tcounds 424

Diphtheritic inflammation 424

Secondary changes 42.5

Fatty degeneration 425 Waxy degeneration — 427

Pigmentary degeneration 426 Colloid corpuscles. 429

Waxy Degeneration of the Cerebellum. By J. Baxter Emerson 430

Waxy Degeneration of the Brain. By .lolm A. Rockwell. 434

XII. Tuberculosis 439

Tuberculosis of the lungs 440

Chronic tuberculosis 440 Tuberculous pneumonia 445

Subacute tuberculosis 442 Acute miliary tuberculosis 447

Tuberculosis of the serous and mucous membranes 448

Chronic tuberculosis 448 Acute m iliary tuberculosis 449

Subacute tuberculosis 449

CONTENTS. xi

I'AiiK.

TubtTCMilosis of the mucous memJjraues 4r)(>

Tuhereulosis and scrofulosis of the lymph-^uiiKlia 451

Tuberculosis of the kidneys. Concomitant nephritis -io'.i

Theory of tuberculosis .... 45()

Anutomicnl iiif/i)s of the hihrrcle 456 Oompariaon with suppuration 402

Titberrnloiis and nrrofiiloun (tiaHiesin. . 404
Uccvnl thcoricH 40(1

Origin of tubercle 458

Further chani/es of tubercle 401

XIII. TCMORS

Detinition

Origin

Composition aiul localization

Benignity and malignity

(a) Clinical and pathological
features 472

(b) Histological features .

Secondary changes ...

Classification 477

4 OS
408
40!)
470

471

474

47t>

1. Myxoma. Mucoid tumor

(a) Myxonia of reticular slriicl-
■ure 479

(b) 2fgxonia of the structure of
the umbilical cord 481

47!>

(c) Myxoma of the stnicturc of the thy-
roid body — so-called lymph-ade-
noma 4H-J

. Fibroma. Fibrous tumor 48;i

(a) Fibroma of loose, fibrous (c) Fibroma of dense, interlacing bun-
connective tissue 484 dies of fibers 480

(b) Myxo-flbroma, or soft fibro- (d) Scar-shaped fibroma. Keloid 480

ma 484 Combinations 480

3. Chondroma. Cai'tilagiuous tumor

4. Osteoma. Osseous tumor

(a) Cancellous or epijjJtyseal or

spongy osteoma 489

r>. Myeloma or sarcoma

(A) Globo-myeloma

(a) Globo-myeloma composed of
laryeplustids 493

4.S()

48!)

(b) Compact or eburncal osteoma 490

Psammoma 491

492

493

(b) Globo-myeloma composed of small
plaslids — lymphosarcoma 493

(c) Glioma or glio-sarcoma 493

(B) Spindle-myeloma 494

(a) Spindle-myeloma composed

of large plaslids 495

(b) Spindle-myeloma composed

of small plaslids 495

(c) Spindle-net myeloma 495

Giant-eell sarcoma of Virchoic 490

Melanotic myeloma 497

49S

(d) Osteo-myeloma 50<)

Alveolar myeloma 502

Combinations of myeloma

(a) Fibro-mycloma 498

(b) Myxo-myeloma 499

(c) Chondro-myeloma 500

Clinical features 503

The Changes of Epithelia produced by Growth of Myeloma. By

Kud. Tauszky 504

Inflammatory changes 506 Transformation of epithelium intomye-

loma-elcments 509

0. Lipoma. Fatty tumor oil

7. Angioma. Vascular or erectile tumor 512

xii CONTENTS.

I'AGK.

(a) Simple angioma 513 Li/m/ihaii(jlotna 515

(b) Lobular aufjloma 513 Emlolhelioma 517

(c) Cavernous angioma 513

Myoma. Muscle-tumor 517

9. Neuroma. Nerve-tumor ,519

10. Papilloma. Warty tumor 521

(a) Homy papilloma 522 (b) Myxomatous jidpiUoma 523

Microscopical Study of Papilloma of the Larynx. By Louis Elsberg 524

11. Adenoma. Glandular tumor 528

Adenoma of the skin 529 Adenoma of the female breast 530

Adenoma of mucous membranes 530 Adenoma of the thyroid body 531

Cysts 531

1 2. Carcinoma. Cancer 533

(a) Scirrhus orhardcancer 534 Cc) Medullary eancer 536

(b) Epithelioma 535 Pathological features of cancer 536

The Origin of the Carcinoma Elements. By E. W. Hoeber 539

Local origin and transmission 544

The Development of Carcinoma in Lymph-ganglia. By A. W.

Johnstone 545

Secondary changes of cancer .547

(a) Fatty metamorphosis 548 (d) Cystic metamorphosis 548

(b) Waxy metamorphosis 548 (e) Pigmentary metamorphosis 548

<c) Colloid metamorphosis 548

The Development of Colloid Cancer. By H. G. Beyer 549

XIV. The Skin 553

1. Subcutaneous tissue 554

2. The derma or cutis 554

3. Blood-vessels 558

4. Lymph-vessels 559

5. Nerves 559

6. The epithelial cover of the integument 561

7. Implantation of the hair 563

8. The hair 569

Shedding of the hair 570 Development of the hair 572

9. The sebaeeons glands 572

10. The sudoriparous glands 574

11. The nails 576

12. The lacteal glands 578

Inflammation of the skin 580

Tumors of the skin 583

XV. The Digestive Tract 586

1. The oral cavity 588

2. The tongue 589

(a) Filiform impillw 589 (c) Circumvallate painllcB 590

(b) Fungiform papiUie 590

3. The pharynx and oesophagus 592

4. The stomach 593

5. The small intestine 597

Yilli 597 Absorption of fat-granules 599

coMhXTS. xiii

(). Tht' hirjjt' iiiti'stim- «;()5

Ulood-rrssrls of Ihr inlmlims i'ltn Xirrfso/ (lir inlisliiirs . 0()8

Li/iuph-rmm-ls »/ the iiiltslinrM <M»7

7. The suHvary glaiuls 008

SaUrtt CIO Crinipoiin ami fli/tlil/ii-ritic iu/l(ttiiina-

Thrugh «10 //'(/(. 610

Catdrrhttl sloiti(ilili.s CIO

XVI. The Teeth 012

Dentine, f'enient, and Enamel. By C. F. W. Bodecker 013

Drnlini-. 613 Enamel .621

(•fluent 616 KesnUs 623

Seek of tooth 619 Uislonj 824

Dentine and Enamel of Deciduous Teeth. By Frank Abbott 029

Secondary Dentine. By C. F. W. Bcidecker 0.'30

Seeondarij dentine, resembling Heeondurij dentine of lamellated

priniaii/ dentine C36 structure 636

Osteo-dentine 638

The Pulp of the Tooth. By C. F. W. Bodecker 640

1. Met/iods 640 fbj Pulp-stones composed of regularl;/

■J. The minute structure of nor- deteloped lamellated bone 648

mal pulp-tissue 640 (c} Pulj>-slones composed of a mixture

i. Pulpitis 643 of regular bone and dentinal

4. Calcification and tcaxy dc- tissue 648

generation. 645 (dj Pulp-stones composed of dentine,

5. Dentini/ication, eburnijica- with the features of primary den-

tiou, and ossification 646 tine 648

laj Pulp-stones of the character History 649

of secondary dentine 647

The Pericementum. By C. F. W. Bodecker 6.52

f^A ) Forms and development . . . . 652 Alveolar abscess 660

' B) Pericementitis 655 Literature 661

Hyperplasia 658 Results 662

Pyorrhoea alceolaris 659

Caries. By Frank Abbott 003

ilethods 663 Caries of cement 669

Caries of enamel 663 Results 670

Caries of dentine 665 History. 671

Destruction of the temporary teeth 073

Development of the teeth 073

XVII. The Liver 675

Portal vein 675

Capillaries of the lobules 676

Hepatic vein 677

Liver epithelia 678

Bile-capillaries 679

Bile-ducts 681

Oall-bladder 683

The Termination of the Nerves in the Liver. By M. L. Holbrook. 684

Pathology 687

Catarrhal or Interstitial Hepatitis. By H. Chr. Miiller 688

Miliary tuberculosis of the liver 694 Syphilitic gumma 694

xiv CONTENTS.

TAGK.

Microscopical Studies ou Abscess of the Liver. By J. C. Davis. . . . 695

Pymmic abscess of the liver 699 IHfjmentary deyenerution 702

Fatly dttjencration 701 Waxy deyeneration 7^'3

Yellow Atrophy of the Liver. By J. A. Rockwell 70;j

XVin. The Eespiratory Tract 700

1. The nasal cavities 709

2. The larynx 711

3. The trachea 712

4. The lungs 713

Pathology 71()

(Edema of the lungs 716 (b) Catarrhal 2>neumonia 722

Pigmentation 717 Tuberculosis 723

Emphysema 718 (c) Plastic interstitial jmeumonia' 725

Inflammation. Pneumonia 718 fd) Supjnirative jmeumonia 726

(aj Cronjions imeumonia 719

Syphilitic Hepatitis and Syphilitic Pneumonia. By J. H. Ripley. . 727
Examination of the sputa : 730

Tuberculous ulceration 731 Myeloma of the lungs 731

Echinococcus of tlie lungs 731

XIX. The Urinary Tract 733

1. The kidneys 734

Renal artery 734 Uriniferous tubules 739

Tufts ' . . . 735 Lymjihatics 743

Veins 738 Nerves 743

Researches in the Minute Anatomy of the Epithelia of the Kidney.

By Henry B. Millard 744

The endothelia of the urinary tubules 747

Nephritis 7i5 1

Acute Inflammation of the Kidneys. By Alfred Meyer 7o3

1. Catarrhal (desquamative, in- 2. Croupous (parenchymatous) ne-

tcrstitial) nephritis 755 phritis 7C0

3. Suppurative nephritis 765

Chronic Inflammation of the Kidneys. By Jeannette B. Greene .. . 707

1. Chronic catarrhal nephritis. 3. Chronic suppurutiee nephritis 774

Cirrhosis 768 Formation of cysts 775

2. Chronic croupous nephritis. . 771 Fatty degeneration 776

Atrophy 772 Waxy degeneration 777

Hypertrophy 773 Results 779

2. The calices, the pelvis, and the ureter 771>

3. The imnary bladder 781

4. The urethra 781

XX. The Urine 783

Normal urine 783

Pathological lu-ine 785

Amount of urine 786 Albumen 786

Pathological constituents 786

Determination of the specific gi'avity •. . . . 787

CONTENTS. XV

TAIiK.

('liriiiic:il tests 7.SS

Ttsts /or siii/ar . THl) 'J'roiiuiicr'n IrsI 7H9

MiiDir's IrsI .. 7H9 Jioberls's /ernienlation ten! 7H'J

JUilli/er's test. 7H'.> FehUno's rnliimrtrir )iiftliinl I'M)

Microscopic exaiiiinatioii 7U(>

ExtronvDua tiiiiltrrs T'.hi Mdi/nrsiimi /iJio.iitlKilr 7'.ii'.

Cri/slalliiic sciliiiiciils . 7'J'J Mucus 7'.»r.

1. I'ric aeid 792 >Spenn 71";

2. Oxalate of liiuc 793 Colloid corpuscles of the prostate (/land ''Jl

3. Urate of soda . 794 Pus-corjiiisrles 7'.iT

4. Hippiiric acid . 7 '1 Diaunosis of the nenvral constitution . . 797

Cj/stinc 795 Ciliiilvd /)iis-cori)USclcs 7L'7

Tj/rosine . 79.") I'ifjincnicd pus-corpuscles 798

Leucine 795 lied Idood-corjniscles 798

5. Urate of Ammonia 795 Ha'maloidin 798

C. Triple phosphates 795 Shreds of connceticc tissue 798

7. Simple phosphates . 705 Fal-i/ranules and fat-r/lobulcs 799

8. Calcium carbonate 7D0

Epithelia S0<)

2[alc urine 801 Common to both scves 80;j

Female urine 803

Tul)iilar casts 804

Ui/aline and epithelial casts . . . 805 (Iran ular and fatty casts 805

Blood-easts 805 Waxi/ easts 800

Entozoa • 808

Hooldets of echinococci 808 Trichomonas vaginalis . 8i)8

Distoma hwmatobiiim 808 Ascaris Inmbricoides 808

Diagnosis from examination of urine 808

Urethritis 808 Villous tumors 810

Prostatitis 809 Pijelitis 810

Vaginitis 809 Ha'inorrhage from the kidneys 810

Cervicitis 809 Catarrhal nephritis 810

Endometritis 809 Croupous nephritis 811

Cystitis 809 Su2»2»i>'(ttii'e nephritis 811

XXI. The Male Genital Tract 81i2

Spermatozoids 812

1. Testis 813

Formation of spermatozoids 814

Terminations of Nerves in the Testicle. By H. G. Beyer 81()

2. Epididymis 818

3. Vas deferens 819

4. Ampulla and seminal vesicles 819

5. Remnants of embryonal formations 820

The paradidymis 820 Hydatid of Morgagni 820

Vas aberrans Halleri 820 Pedunculated hydatid 820

6. Prostate gland 820

7. Cowper's glands 821

8. Penis 822

XXII. The Female Genital Tract 824

xvi CONTEXTS.

I'AfiE.

The o%iira ^--4

Detenn ination of *< j- 824

1. Ovary 825

Follicles 826 Bemains of embryonal fonualions. .829

Corpus luteum 827 Epooplioron 829

Paroophoron 829

12. Oviducts 829

:;. Uterus 829

Pathology of the uterus 831

Catamenial decidua. By Jeannette B. Greene 832

4. The vagina and external genitals 838

The placenta and the umbilical cord 839

A Contribution to the History of the Development of the Human

Decidua. By J. W. Frankl 839

Waxy Degeneration of the Placenta. By Jeannette B. Greene 842

Waxy degeneration of the am- Waxy degeneration of the nmhilical

nion 847 cord 847

Conclusions. . . 849

LIST OF (OX 1 niiu Tons.

Frank Abbott, M. I)., New- York.

TLe Minute Auatouiy i)f Deiitim- and Enaiucl. The Dental Cosmos, Philartelpliia,
1880. Abstrat-t: "Dentine and Enamel of Dfcicluous Teeth." Pa^e «29. Carien of
Iliuuau Teeth. The Dentul Cosmos, Pliiladelphia, 1878 and 1879. Aljstract : "Ca-
ries." Page G63.

H. G. Beyer, M. D., M. R. C. S., Passed Assistant Surgeon,
U. S. Navy.

Microseopieal Studies on Ab.scCKS of the Braiu. Jourmtl of Xcrvous and Menial Dis-
ease, ChicafTo, July, 1880. Abstract. Page 407. A Contribution to the IliKtory of
the Development of Colloid Cancer. T/ie Medical Gazette, Xew-York, April, 1880.
Abstract. Page 549. The Terminations of the Nerves iu the Testicle. Printed in
abstract from the author's mamiscript. Page 816.

C. F. W. BoDECKER, D. D. S., M. D. S., New- York.

Necrcsis. The Dental Cosmos, Philadelphia, 1878. Abstract. Page 390. The Distri-
bution of Liviug Matter iu Human Dentiue, Cement, and Enamel. The Dental
C'osMios, Philadelphia, 1878 and 1879. Abstract: "Dentine, Cement and Enamel."
Page 013. Secondary Dentine. The Dental Cosmos, Philadelphiii, 1879. Abstract.
Page 630. On Pcricementuiu aud Pericementitis. The Dental Cosmos, Philadelphia,
1879-8'. Abstract: " The Pericementum." Page Ooi. The Minute Anatomy of the
Dental Pulp in its Physiological and I'athological Conditious. The Dental Cosmos,
Philadelphia, ;882. Abstract : " The Pulj) of the Tooth." Page 640.

J. C. Davis, M. D., New-York.

Microscopical Studies ou Abscess of the Liver. AT-chires of Medicine, August, 1879.
Al)stract. Page 695.

Louis Elsberg, M. D., New- York.

Notice of the Bioplasson Doctrine. Transactions of the American Medical Associa-
tion, 1875. Pages 57, 135. The Structure of Colored Blood-corpuscles. Annals of the
Xew-Tork Academy of Sciences. Vol. I. 1879. Page 64. Microscopical Study
of Papilloma of the Laryux. Archives of Laryngology, New-York. Vol. I.

1880. Abstract. Page 524. Coutributions to the Normal and Pathological Histol-
ogy of the Cartilages of the Larynx. Archives of Laryngology, New- York. Vol. XL,

1881. Vol. III., 1882. Pages .57, 185, 206, 305.

J. Baxter Emerson, M. D., New- York.

Perieucephalitis. Journal of Xervous and Mental Disease, Chicago, April, 1880.
Abstract : " Waxy Degeneration of the Cerebellum." Page 430.

J. W. Fraxkl, M. D., New- York.

A Contribution to the Historj- of the Development of the Hiunau Dccidua. Ameri-
can Journal of Obstetrics and Diseases of Women and Children. Vol. XI. October,
1878. Abstract. Page 839.

xviii LIST OF COXTBIBUTOJRS.

Jeanxette B. Greene, M. D., New-York.

C'bionic Inflauiiuatiou of the Kidneys. Printed from the author's munusrript.
Page 767. Waxy Degreneratiou of the Placenta. American Journal of Obstetrics-
and Diseases of Women and Children. Vol. XIII. 1880. Abstract. Page 842.
Microscopical f^tiulies on the Catamenial Decidua. The A merican Jourmd of Obstet-
rics and Diseasesof Women and Children. Vol. XV. April, 1882. Abstract. Page 832.

WiLLLOi Hassloch, 31. D., Xew-York.

The Structure and Growth of Some Forms of Mildew. Xcw Tori: Medical Journal.
November, IHIS. Page 40. Researches on the Microscopical Structure of the
Cornea. Ardiices of Opthahnology and Otoloijtj. Vol. VII. 1878. Page 171.

C. Heitzmaxn, M. D., New- York.

Zur Keuutniss der Diinndarmzotten. Sitzungsber. dcr Akademic der Wissen-
schaften in Wien, IvUi. Bd. 1868. Abstract. Pages 401, 600. Stndien am Kuocheu
imd KuoriK'l. Wiener Med izinische Jahrbiicher. 1872. Pages 98, 11.5,198,221,250,
356. Ueber die Riicb- und Xeubilduug von Blutgefasseu im Knocheu und Knoriiel.
Wiener Medizini.fche Jahrbiieher. 1873. Pages 118, 231, 244, 342, 3.5G, 373. Ueber
Kiinstliche Erzeugimg Ton Rachitis und Osteomalacie an Thieren. Anzeiger der
Akademie der Wissenschaften in Wien. 19 Juui, 1873. Vorlrag in der Gescllschafi
der Aerztc in Wien. October, 1873. Uutersuchungeu iiber das Protoplasnia. I.
Bau des Protoplasmas. Sitzunysber. der Kais. Akademie der Wissenschaften in
Wien. April, 1873. Page 21. II. Das Verhiiltuiss zwischeu Protoplasma und
Grundsubstauz im Thierkoi-per. Hitzutujsber. der Eais. Akademic der Wissen-
schaften in Wien. Mai, 1873. Page 115. III. Die Lebeusphasen des Protoplasmas.
Sitzungsber. der Eais. Akademie der Wissenschaften in Wien. Juni, 1873. Page 46.
IV. Die Eutwickelung der Beiuhaut, des Kuocheus und des Knorpels. Sitzungs-
ber. der Kais. Akademie der Wissenschaften in Wien. July, 1873. Pages 179,
212, 247. V. Die Entziindung der Beinhaut, des Knocheu s und des Knorpels.
Sitzungsber. der Kais. Akademie der Wissenschaften in Wioi. July, 1873. Page
356. Ueber Tubcrkelbildung. Wiener Medizinische .Jahrbiieher. 1874. Page 439.
The Cell Doctrine in the Light of Recent Inve.stigatious. A paper read before
the County Medical Society of New York, 1876. Xeic York Medical Journal.
1877. Pages 13, 30. On the Nature of Suppurative Processes of the Skin. A paper
read before the County Medical Society of New York, 1877. Uuprinted. Page 59.
The Aid which Medical Dia.gnosis Receives fi-om Recent Discoveries in Mi-
croscopy. A paper read before the County Medical Society of New York, 1878.
Archives of Medicine, New York, February, 1879. Pages 58, 140, 474. Epithelium
and its Performances. A paper read before the American Dermatological -Associa-
tion, at their meeting in Saratoga, August 27, 1878. Pu1>lished in abstract. Xetc York
Medical Journal. 1878. Page 311. Microscopical Studies on Inflammation of the
Skin. Read before the American Dermatological Association, New York, August 27,
1879. Published in abstract iu The Chicago Medical Journal and Exanti)icr, Octo-
ber, 1879. Page 580. Tumors of the Skin. Read before the American Dermato-
logical Association, Newport, R. I., August, 1880. Printed in abstract in Archives
of Dermatology, Philadelphia, October, 1880. Page 583. A Contribution to the
Minute Anatomy of the Skin. Read before the American Dei-matological Asso-
ciation, Newiiort, R. I., September 1, 1881. The Chicago Medical Journal and
Examiner, December, 1881. Page .563.

E. W. HOEBER, M. D., New- York.

Ueber die erste Eutwicklung der Krebselemente. Sitzungsber ichte der Eais. Aka-
demie der Wissenschaften in Wien, 1875. Abstract: "The Origin of the Carcinoma-
Elements." Page 539.

M. L. HoLBROOK, M. D., New- York.

The Structiire of the Muscle of the Lobster. Printed from the author's manuscript.
Page 274. The Termination of the Nerves in the Liver. Printed in abstract from
the author's manuscript. Page 684.

LIST OF CONriUnUTOIiS. xix

A. M. HuRLBUTT, New- York.

The Stnictiiro of tlu- Elooil-forpusilt'M of tin- Oyster. .Srii-lOrL- Malicnl Joiiniiil,
January, 1879. Abstraet. Pn'<e 37.

A. W. Johnstone, M. D., Danville, Ky.

Experimental and Mieroseopieal i*tn<Hes on tlie Origin of tlie Ulood-^'loltulcM.
Art-hires of Medici lie. Vol. VF. .Vn^nst, 1881. Pa^e 105. The Develoitnuiit of Car-
einonia in liyniith-jranfrlia. Printed in abstraet from the author's mannserijit.
Pajre 545.

Alfhed Meyer, New- York.

rutersuehunfjen iiber aeiite NiereuentziindunjL?. Silzungsberirhte dcr Kais. Ak<i-
deiiiie der ^yissellschaftell in Wien, Ixxv. Rd., 1877. Translated by the author.
Abstraet. Page 753.

Henry B. Millard, A. M., M. D., New-York.

Rosoarelies in the Minute Anatomy of the Epithclia of the Kidney. The \eir-York
Medical Journal, June, 1882. Abstraet. Page 714.

H. Chr. Muller, M. D., New- York.

Beitriige zur Kentuiss der interstltielleu Leberentziiuduug. Sitzungsberichte der
Eais. Akadeniie der Wisseiischaften in Wien, Bd.lxxiii. 187C. Abstract. Page 688.

J. H. Ripley, M. D., New- York.

Syphilitic Hepatitis and Syphilitic l*ueumouia. Printed front the author's ntana-
scri2)t. Page 727.

John A. Rockwell, M. D., New-Y''ork.

A Contribution to the Pathology of the Brain. The Xeir England Medical Gazette,
March, 1882. Abstract: "Waxy Degeneration of the Brain." Page 434. Micro-
scopical Studies in Y^ellow Atrophy of the Liver. The New England Medical
Gazette, June, 1882. Abstract. Page 703.

L. ScHONEY, M. D., New- York.

Ueber den O.ssificatiousprocess bei Vogeln, und die Neubilduug von rothen Blut-
korpercheu an der Ossificationsgreuze. Archiv fiir Mikroskopischc Anatomie,
Bd. xill. Abstract. Pages 103, 251.

Rudolph Tauszky, M. D., New^-Y^ork.

Ueber die durch Sarcom-Wucherung bedingten Vei'anderungen des Epithel.^. Sitz-
ungsberichte der Kais. Ahademie der Wissenschaften in Wien, Bd. Ixxiii. 1875.
Translated by the author. Abstract. Page 504.

METHODS,

THE methods of preparation of the liquid and solid constit-
uents of the animal liody are of the utmost importance.
Every progress in histology is largely due to an ini])rovement in
the methods of i)reparation employed as well as of the optical
apparatus.

The main purpose obviously must l)e to examine liquids and
tissues in a condition as nearly as possible like that in which
they exist within the living body. The history of histologj-
teaches that the greatest errors have resulted from a neglect of
this rule. From the moment a specimen for examination with
the microscope is allowed to dry, such a specimen has become a
mummy, and unfit for further research. Almost all tissues, in
former times, were allowed to dry before their minute structure
was examined. The results of such researches are considered
worthless nowadays. Despite of all experience gained in the
last four decades, — that is, the time in which microscopic mor-
phology has gradually developed into a science, — even in our
day, dry bone-tissue is examined in all laboratories ; but such
examinations are necessarily of very small value. Another
objectionable procedure is the tearing, teasing, and pulling of
tissues. By such methods, the parts which in the body are
connected become l)roken and disfigured, ih'hris are produced,
sometimes with the greatest skill, which, as a matter of fact,
are useless for fruitfid microscopic investigations. Both me-
chanical and chemical isolation of the constituent parts of tissues
should be used to a very limited degree only. Just as objection-

2 METHODS.

a))le is boilings, or a complicated chemical treatment, which, as a
nile, yields results far from the truth.

Infusion. Among the liquids useful to he examined for bio-
log'ieal purposes first ranks the " infusion." Torn blades of
grass are, with the careful avoidance of the admixture of
particles of earth, transferred to a china soup-plate, common
water is j)()ure(l upon them, and they are left uncovered and
undisturbed at the temperature of the laboratory. To make up
for evaporation, some water may caiitiously be added from time
to time. After from six to ten days, sooner in summer than in
winter, this liquid will swarm with newly formed organisms, the
study of whicli is most fascinating to the biologist. A droplet
of the infusion is brought on a glass slide, covered with a thin
covering-glass, and is a ready specimen for microscopic research.

If we mix together some water with orgiuiized bodies, such as grass,
apparently destined to decay, there will sprout up a remarkably rich gener-
ation both of plants and animals. To explain this fact is quite difficult.
Some observers believe that the decaying particles of vegetables themselves
change into new orgaiiisms imder favorable circumstances ; while others, and
doubtless the majority, are of the opinion that there are floating in the air
millions of invisible germs of plants and animals, which, on finding a favorable
soil for development, begin to grow and prosper. The germ-theory, first
thoroughly established by Pasteur, has not as yet been contradicted in a
satisfactory manner; we have, therefore, every reason still to adhere to it.
Certainly no development of infusoria takes place if the air be prevented
from reaching the infusion.

Among the numerous organisms in a drop of infusion perhaps
the most elementary is the amoeba, which is best obtained from
the border of the infusion in the plate, or from the blades of the
decaying grass, gently scraped with a knife. The amoebge are
pale, with lower powers of the microscope finely granidar, trans-
parent lumps, which continually change their shape and locality.
In the first few weeks after the ^preparation of the infusion, we
olitain amoebaj of the shape and motion of caterpillars, which are
the most suitable for microscojDic examination, especially if in
slow motion.

It is remarkable that I succeeded in raising almost identical fonns of living
organisms on mixing together the same material several thousand miles away
from New York, viz., in Vienna. There is a slight difference, however, im-
portant enough to be mentioned. In Viemia I never saw an ama'ba without
a distinct lump in its interior, the nucleus ; while in New York, the more
common occurrences are ama-bse without nuclei. As these animalcules are
identical in every other respect, both in Vienna and New York, this fact

MF/niODS. 3

disproves the opinion of many histolot^ists that tlie nueleus is soniethiiij^
essential to the so-called " nnicellular" orpmisni. Haeckel's view, viz., that
there is a marked ditTerence between forms devoid of a nueleus, termed by
him •' eytodes." and those with nuclei, termed "cells," must be considered
to be untenable.

Moist Vhiimhev. Von Reckliii<;hauseii inveuted the moist
chamber for the purpose of ]>reventiii^ mierosco])ie specimens
from evaporation, witliout cutting oft" the sup])ly of air. 3Iany
devices have been invented for this jturpose. One of the simpk^st
is L. Ranvier's — a shde on wliieh a circular furrow, for holding
air, surrounds the central plane surface ; on the latter a droplet
of the liquid is placed, and the covering-glass, which must be
large enough to cover the whole of the furrow at its edges, is
hermetically sealed to the slide by a frame of melted paraffine.
S. Strieker uses a slightly elevated frame of glazier's cement, on
the top of which he sticks the covering-glass holding the speci-
men, while a droplet of water on the bottom of the chamber
supplies moisture. The same investigator uses a moist chamber,
which, for examinations not exceeding one or two hoiu-s' dura-
tion, proves to be the best and simplest of all. He oils the edge
of one side of the covering-glass, and after having transferred a
droplet of the fresh liquid to the slide, he covers it so that the
oil-frame of the covering-glass adheres to the sm'face of the slide
around the specimen.

Heatuhh Stage. Max Schultze introduced the so-called heatable
stage with the view of keeping up in a specimen the temperature
of the l>ody, or raising it at will. As a matter of coiu-se, liquids
of cold-blooded animals, especially their blood, need no such
apparatus. A droplet of blood of the newt (triton, salamandra),
which we obtain by cutting otf the end of the tail of the animal
with a pair of scissors, may be transferred upon the slide by
simply touching the wound. The specimen must immediately
be covered with a very thin covering-glass, the edges of which
have been oiled beforehand. With a little skill, a specimen is
obtained fit for examinatic^n even Avith the highest powers of the
microscope. The warmer the temperature of the room the
sooner the colorless blood-corpuscles will begin to change then-
shape and location. They will prove to be identical with the
amoebte found in an infusion of grass. The examination of
the colorless blood-corpuscles, or other isolated bioplasson bodies
of warm-blooded animals, by means of the heatable stage, has
proved their identity also with amdebte. Such bodies within the

4 METHODS.

tissues may, as long as they i-eniain alive, exhibit under the
heatal)le stage changes of shajje, hut, on aeeount of their })eing
inihedded in basis or cement substance, no loc^omotiou.

The heatable stage of S. Strieker is a shallow metal case, the
central cavity of which is connected with small pipes for the
conduction of gases to l)e Tn-ought in contact with the living
specimen. The latter rests on the lower surface of the covering-
glass. In front of the case a metal peg can be connected with a
spiral copper wire, the distal extremity of which is heated over
an alcohol or gas lamp. The temperature is shown by a small
thermometer outside the case. If a drop of blood be inclosed
between two thin covering-glasses, with greased edges, the
phenomena of amoeboid motion and locomotion are much better
observed than in a drop hanging on the lower surface of one
cover only. For high powers of the microscope, a condenser of
light must be put into the diaphragm of the stage, as a good deal
of light is lost on account of the unavoidable depth of the stage.

Uln-fricifi/. Li\dng specimens are sometimes exposed to the
influence of the electric cui'rent, preferably the induced, inter-
rupted, as that alone admits of proper action upon the specimen.
Both the constant and an induced cm-rent extending over several
minutes are objectionable, as electrolysis with formation of gas-
bubbles occurs, and the thermic action may destroy the effects
of electricity upon the specimen. The simplest apparatus for
applying electricity under the microscope is that of E. Briicke.
A glass shde is covered with strips of tin-foil, between which, in
the center of the slide, rests the specimen. The lower surface
of the glass slide, also covered with tin-foil, is moved on two
parallel copper supports attached to a larger glass plate, and in
connection with the electrodes.

Preparation of Fresh Tissues. Tissues from the freshly killed
animal are, as a rule, unfit for microscopic research beyond a
limited time. There is no liquid which keeps the specimen un-
changed, and, without the addition of some liquid, the specimen
soon dries. As preser\ang fluids have been iised the liquid of the
anterior chamber of the eye, sermn of blood, the amniotic li(piid
of calf or sheep embryos, with the addition of a little metallic
iodine, normal urine, one-half per cent, solution of chloride of so-
dium, very dilute solution of bichromate of potassa, etc. The two
latter answer all purposes. Water is objectionable, as the bio-
plasson matter swells and becomes destroyed l)y it ; the same
destructive action is noticeal>le on the addition of glycerine.

MirriioDs. 5

Frt'sli sju'cinHMis, if in the sh;i|M' of delicate nieniliraiies, are
spread over the glass slide, while, if in the shape of masses not
transparent, they are ent with the nizor in a frozen condition.
The free/inu- mixture may l)e snow oi- hroken ice with salt in one
compartment of a metal 1k)X, while the other compartment holds
the specinieu, fixi'd, if necessary, by mucilage of gum arable.
Numerous freezing microtomes have been invented; in some,
rliigolene or ether-spi-ay is i)roduced, by means of which a fresh
specimen may in a few minutes be frozen to such a consistence
that it can be cut with a razor. Specimens so obtained are
useful for temporary examinations or for staining, especially
witli chloride of gold. Freshly cut specimens may be preserved
by tlie addition of a very ddute solution of l)icliromate of po-
tassa, which is aUowed to flow under the covering-glass, and is
drained off by strips of faltering ])aper held against the edge of
the cover.

Preservation of Tissues. The best method of preservation and
hardening of normal and morbid specimens is to divide a large
mass of the tissue by incisions into small pieces, of one or two
inches diameter, and to place these pieces in a wine-yellow solu-
tion (one-half per cent.) of chromic acid. The chromic acid is kept
ready in strong solution, of which a small quantity is added to the
water holding the specimen in a glass jar. It is important that
the specimens be placed in a large quantity of liquid, its hulk
exceeding that of the specimen at least five or six times. These
precautions are necessary, as the hardening action of chromic
acid does not penetrate very deeply. In t)ne oi- two days, the
liquid having become cloudy, the chromic acid solution must be
renewed, and such renewal is to be repeated every few days until
the solution remains clear. Specimens of bone or teeth are
treated in the same manner, and the extraction of the lime-salts
may be hastened by a very cautious addition of dilute muriatic
acid every foui'th or fifth, day. If the chromic acid be apphed in
this way, it hardens the tissues in a few days or weeks, with
no other change than a slight shrinkage, and renders them fit
for cutting with the razor. After the specimens have been
hardened, we still may keep them in very dilute solutions of
chromic acid, to which we add small quantities of alcohol in
order to prevent the growi:h of mildew, the most unpleasant
enemy of a laboratory for microscopic research.

A dark wine-yellow solution of bichromate of potassa is also
suitable for the preservation of specimens, though in such a

6 METHODS.

solution hardening goes on very slowly, or not at all. The
hardening may he aecomplislicd by the solution of ehroniic acid
as described above, or by alcohol. The latter method is the best
for preservation of l)rain specimens, which, by the slightest
excess of chromic acid, Ix^come too l)rittle to be cut. Eyes are
placed fresh into Miiller's liquid (two parts of bi(;hromate of
potassa, one part of sulphate of soda, and 100 parts of water).
After a few weeks the eye may be cut open and transferred into
a one-half per cent, solution of chromic acid, or into strong alcohol,
in order to accomplish the hardening process. The advantage of
these re-agents is that they do not interfere with the structure
of the tissue, and render all constituent parts very distinct.
Chromate of ammonia or picric acid solutions are by no means
superior to the above-described liquids. Alcohol, for preser-
vation of specimens, is objectionable, as it makes the tissues
shrink, and leaves them too pale and indistinct for good observa-
tion. Specunens kept in alcohol for a while should be placed in
a one-half per cent, solution of chromic acid, in which they harden
very quickly, and become well adapted for microscopic purposes.
Bone and teeth, after a long-continued action of chromic acid,
on account of the reduction of the latter, assume a dark green
color, without change of their structure.

Cuffing. After the specimens have become sufficiently hard,
they are i-eady to be sliced into thin and transparent sections.
For this purpose a good razor, flattened on the side which slides
on the specimen, is the simplest and most convenient tool. The
specimen is rid from chromic acid by being placed in water ; it
is held in the left hand, flattened out by one stroke of the razor,
and the flat surface is kept in a horizontal position over a china
soup-plate filled with water. We take up a little water on the hol-
low surface of the razor, and, while the water runs over the level
of the specimen, the razor is drawn slowly and unifoi-ndy through
the tissue without producing ridges. The thinner the specimen
the better. With the assistance of a flat copper spoon and a
needle, the thin sections are transferred to a china saucer hold-
ing water, in which, if desired, staining re-agents are applied.
Common water answers all purposes, and neither alcohol nor
distilled water are required. Small or hollow specimens, which
cannot be held in the left hand, such as halved eyes, teeth, etc.,
must he imbedded in the following way: The hardened specimen
is placed in strong alcohol for twelve to twenty-four hours, in
order to l)e rid of its water. A square paper box, according to

Mirr NODS'. 7

the size and sluipc of the s|)c<'iiii('ii, is iiukIc ; we fill the l)(»ttom
■with !i iiu'ltcd niixtiu't' of pai'amiMc and wax, six or fi^ht parts
of the former t(» owe of the latter, with the addition, perhaps, of
a. little nintton-tallow. As soon as the layer of the niixtnre in
the box heeomes cloudy, tlie s])eeiinen, from which the surplus
of alcohol meanwjiile was allowed to evaptn-ate, is ti'ansferred
into the hox, and the j)araffine mixture, not too hot, is poured
over it. The hox, when full, is j)laee(l in cold water, where the
surronntlino- paper is destroyed, and the fat becomes hard in a
short time. The sections are made simultaneously throug'h the
paraffiue aud the specimen, in the same way as described before.
No clearin<>' re-at»'euts, such as turpentine or oil of cloves, should
be used ])efore imbedding- the specimen, as such re-agents render
the details of the structure indistinct. 'Small specimens may be
fitted into two pieiies of the best so-(!alled velvet-cork, properly
hollowed out, and cut together with the cork.

Everybody can learn to cut sections by more or less practice,
though a certain amount of cleverness and steadiness of the
hands is i-equired to reach perfection. The rule is, that the
section should be very thin, transparent, while its size is of much
less importance. Valuable specimens, of which very little ought
to be lost, may be cut with a section-cutter. The simplest style
is a metal tube mounted at right angles with a circidar black-
glass or India-rubber plate. The centi'al perforation of the plate
opens into a cylindiical metal box of varying diameter, which,
by means of a screw, slides within the metal tube. The paraifine
mixture is poured into the metal box, and the imbedded speci-
men is gradually lifted to the level of the plate, over w^hich the
flat surface of the razor-blade is passed. Complicated cutting-
machines, in which the blade of the knife works on the principle
of a plane, are invented in large number, and prove to be
satisfactory in the hands of their inventors, or whenever a large
number of specimens is required for distribution or for trade.
The greater the complication, the less is the value of such
machines.

Mounthu). The sections, after being stained, are transferred
on a metal spoon with the assistance of a needle. The best
spoon for the purpose is one made of hammered copper wii'e, the
flattened and rounded extremity of which is at a right angle to
the wire, the latter constituting the handle. Perforations of
the spoon are superfluous. The sm*plus water is soaked away
from the lower surface of the spoon l)y means of good white

8 METHODS.

filtering-paper ; a dro]) of dilute glycerine is added — best with the
glass stem of the hottlc liolding glycerine — to the specimen, which
is then worked down to the center of a glass slide. Here the
specimen is spread out, if necessary, with two needles, its position
corrected, and the covering-glass gently placed over the drop, so
as to avoid including aii--l)ul)])les. With a little pra(;tice and
skill we learn to add the exact quantity of glycerine. Should
the drop prove to he too small, — \t.z., if a (corner or edge of the
covering-glass wants glycerine, — a small droplet is approached to
that edge, and will flow under by capillary attraction. If too much
glycerine be taken, it must be drained off l)y moist flltering-paper,
and the slide cleansed carefully with a j)iece of such paper folded
up and moistened. The sealing together of both glasses should
be accomplished by painting varnish in the shape of a narrow
but heavy rim along the edge of the covering-glass ; but great
care must be taken to have both slide and cover first absolutely
clean and dry.

The only liquid which can be fully recommended for mount-
ing hardened specimens is glycerine in the purest chemical
condition, to which distilled water (aljout one part of water to
three parts of glycerine) is added. Mounting in Canada balsam
or in damar varnish is objectionable, as the specimens in these
liquids in time clear up to such an extent as to become unfit for
ampHflcations of the microscope exceeding 300 or 500 diameters.
Long-continued trials, as regards the value of both methods,
have led me to this conviction. Specimens of any description,
mounted in Canada balsam or in damar varnish, are not suitable
as test objects. To-day, the power of definition of a lens shoidd
be tested exclusively on living objects, such as infusion organ-
isms, fresh blood corpuscles, saliva corpuscles, etc. The process
of mounting in glycerine is simpler and easier than any other
method, and, if all precautions mentioned are carried out with
care, no change of the specimen will take place. True, glycerine
specimens need more careful handling than balsam specimens,
but their value is decidedly greater than that of the latter.

In order to make glycerine mounting safe, it is preferable to
delay applying the varnish for twenty-four hours, as the surplus
water by that time will have evaporated. Should too little
glycerine be used, the inclosing varnish will run under the cover
and deprive the specimen of its neat appearance ; shoidd too
much glycerine be left between the two glasses, it often happens
that after months or years the glycerine finds its way through

Miri/foDs. 9

the rim of varnish, and the siH'cinicn l)e('<)nies si)()iled. As an
inchtsinir varnish, asplialt dissolved in tnrpentine is f^enerally
used, thonjj^h any ntlicr vai-nish answers the pnrpose if ])ut on
in suffieient (piawtity. The ni()untin<i: and varnisliinj; «»f •glycer-
ine specimens is easier with sc^nare than with circnlar covering-
classes.

Sf<iiiiinf/. The amnioniacal carininc solnti<)n ((lerlach) is the
most satisfactory for stainini^ specimens obtained after hardening
in chi-omic acid solution. To the best cochineal powder we add
distilled water and a few di'ops of aqua ammoniap fortis, until
the cochineal is c(mipletely dissolved. The amount of the car-
mine solution to be poured into the saucer holding the sections
depends on the concentration of the solution. The best way is
to take but little carmine, and let it act on the specimen for
twenty-four hours. The various compounds of carmine in use
may be dispensed with, as all carmine staining is very unreliable,
and, except for the handsome appearance it gives to the speci-
men, of no material valiu\

HamiatoxyL)n (logwood) and eosine are re-agents used for
alcohol specimens exclusively, but not suitable for chromic acid
preparations. The action of the picric acid is kindred to that of
chromic acid. AniUne colors as a rule are not fast, neither are
solutions of picro-indigo.

Osmic acid (M. Schultze) in a one per cent, solution stains fat
black in both the fresh and the preserved condition of the speci-
men ; it renders the c( )ntours of the tissue, especially nervous tissue,
more distinct, but other-wise has a very limited value.

Important re-agents are the nitrate of silver (Von Reckling-
hausen) and the chloride of gold (Cohnheim) ; though specimens
treated \nth either of these re-agents become indistinct after five
or six years. Nitrate of silver is brought into contact, in a one
per cent, or two per cent, solution (kept in black bottles), exclu-
sively with fresh specimens, for only a few minutes, or used for
injections into blood and lymph vessels. Distilled water is needed
for washing off the re-agent. The solid nitrate of silver may be
applied directly on dense tissues, such as cornea or cartilage,
though the layers which come in direct contact with the stick
are destroyed. Silver-stained specimens are suitable for glycer-
ine mounting.

Chloride of gold is invariably used in a one-half per cent,
solution, and is fit for fi-esh and frozen specimens, as well as for
those preserved in chromic acid ; in the latter case, after careful

10 . METHODS.

soaking in distilled water. The exposure to this re-agent may
vary from fifteen to sixty niinntes, or even over this time. After
the re-agent is washed off with distilled water, especially for
staining nerves, a few drops of acetic, tartarii;, or formic acid
may be added. Such specimens are mounted in glycerine.

Al)solute alcohol (Spina) is a re-agent which has recently
become of ini})ortance for bringing to view certain features
in the varieties of connective tissue. The tissue is kept for only
two or three days in alcohol, cut and examined in alcohol, but
cannot be preserved.

I)ij('riions. In order to render the vessels of a tissue plainly
visible, stained liquids are driven into them. The best liquid is
fine melted gelatine, stained red with carmine, or blue with
soluble Prussian l^lue. As a rule, the injection is made into a
larger artery, whence the liquid spreads through CMpillaries and
veins. The artery is fastened to a small metal or glass tube
fitting at one end the caliber of the artery, at the other end the
caliber of the tube of the syringe or other apparatus. All other
vessels must be ligated except one vein, which, by emptying
the injected liquid, indicates a complete filling of the vascular
system. Both the gelatine and the tissue must be kept at a
temperature preventing coagulation. The injection is made by
a syi'inge, or by more complicated pressure apparatus, which
latter, by their slow action, yield better residts than the former.
Injected specimens are placed and kept in alcohol, as the chromic
acid solution destroys the colors added to the gelatine. Spon-
taneous injection has been used on frogs. So-called parenchy-
matous injections, in which colored liquids are di-iven with a
pointed syringe directly into the tissue, were thought to be of
great value at one time, but they are aljaiidoued nowadays.

How to WorJx- with the Microscope. After a specimen is trans-
ferred to the table of the stage of the microscope, and by the
coarse adjustment or by pushing the tube is brought into focus,
one hand is placed on the fine adjustment, tlie micrometer screw,
and should not be removed during the examination. Both eyes
must be kept open, and no ocular accommodative power exercised,
as the careful handling of the micrometer screw renders accommo-
dation superfluous. Every specimen should T)e examined at fii'st
with low powers of the microscope, and a gradual increase of
the power is accomplished by changing the systems of the
objectives. For illumination of the object we use dispersed day-
light or kerosene-light, which latter is tar superior to gas-light.

MirnioDs. 11

For l<iw i»o\vrrs. tlir |>laii(' inirroi- iiiid tin- larj^t' diapliraf^n are
in (»i"(lcr, while liiiilirr powt rs r('(|iiii-<' the ns«* of the concave
mirror and small diaplii-aiiiiis. .Ml powers of the microscope
exceeding: SOU diameters are reached to-day ))y immersion lenses.
If an immersion lens be emph)yed, tlie microscope should be
])laced at a certain distance from the window, or else kerosene-
liirht be resorted to. For rest^arches with immersion lenses in
dayli<;ht, the time between eleven and two o'clock is the l)est,
thoujfh light-eoudensiug lenses placed below the level of the
specimen may i)rove useful at other times of the day.

As soon as investigation commences, the note-l)ook and the
pencil must be on hand, in order to fix every observation on
paper, thouprh even in no better shape than that of a rough sketch.
Nol)ody can ])e a good observer with the microscope unless he is
a draughtsman. If the eyes be not educated in seeing, and the
hand in reproducing on paper what the eyes perceive, all efforts
to gain correct ideas of what the microscope teaches are in vain.
To see with the microsc<)i)e is a difficult art, re(|uiring many
years of thorough education. The assistance of a rehable
teacher cannot be dispensed mth, for in the art of microscopy
no autodidact can reach perfection any more than in any other
art. Learn to draw, if you desire to see with the microscope.

A number of devices have been invented for facilitating the
di-awing of microscopic specimens by means of prismatic glasses.
All these are supertluous. If we want to represent a microscopic
image on paper, exact in size and shape, we place the paper at
the height of the stage of the microscope, very near the right
side of the specimen. Looking into the eye-piece with the left
eye, keeping the right open, the image is seen i)rojected on the
paper, and the point of the pencil can exactly follow the outlines
on the image itself.

A great deal of time is wasted by apjdying manifold staining
methods to microscopic specimens, and they are deceived persons
who imagine that the value of a specimen is the greater the
nearer it approaches a rainbow appearance. In wasting time
by projecting images on screens by means of complicated mechan-
isms, many forget that microscopy can reaUy be learned only by
handling the microscope, and both eyes and judgment can be
educated only by looking into the microscope itself. Too great
stress is laid, also, on photographing nucroscopic specimens.
Those who are delighted with nice staining of microscopic
specimens, splendid projections on screens, and large micro-

12 METHODS.

photographs, generally lose sight of the aim of the microscope.
We have better things to df) than to play with methods of stain-
ing and projections. We study the relations of jdiysiologieal
and morbid ax)jjearanees to their anatomical bases — a more serious
and diffieidt task. Photographing microscoi:)ical specimens has
reached its highest jjerfection in America, where technical talent
is so remarka1)ly developed. Although such photograjjhs are
useful in certain respects, their value should not be over-
estimated, because they are indistinct wherever the specimen is
not even, or shows several strata. Under such circumstances,
photogi-aphs can hardly replace drawings made by an experi-
enced and conscientious observer.

II,

GENERAL PROPERTIES OF LIVING MATTER.*

LIVING, or organized, matter is the substauee which builds
up plants as well as aninuils — the simplest infusorium as
well as the most highly developed inammal.

Clieniisfri/. The question what living matter really is^ cannot
yet be answered from a chemical stand-point, and there is reason
to doubt whether it ever will ])e settled, inasmuch as it is impos-
silile to obtain pure li\'ing matter in a quantity sufficient for
chemical analysis. As every substance, also, the living matter
must necessaiily be composed of minute particles, whicli can
never be seen, even with the highest magnifpng powers, /. p., the
simplest units, the so-called molecules, whicli admit of no further
division. After Elsl)erg''s at present almost generally adoi)ted
designation, we shaU term the molecules of the living matter
'' plastidules." Molecides. again, are composed of simple ele-
mentary atoms, the (piantity and nature of which give the
essential character to every substance. ' While the molecules of
inorganic bodies are formed by relatively few atoms, we know
that the plastidides are much more complicated in their atomi.stic
construction. Every })lastidule is constituted >)y at least five
elements, namely: carbon, oxygen, nitrogen, hydrogen, and
sulphur. The nature of the union of these elements is a very
complicated one in every i)lastidide. but not as yet elucidated.
We generally call the organic substances simply proteinates, or

* "The Cell Docti-ine in the Light of Recent Investigations, " .\>»r York-
Medical Joiinidt, IS 77.

14 GENERAL PROPERTIES OF LIVING MATTER.

albuminates, conipreliencling by these terms both the living-
matter and its derivations or products. According- to Hoppe-
Seyler, the proteinates are composed of: carbon, 51.5 to 54.5 per
cent.; oxygen, 20.9 to 23.5 percent.; nitrogen, 15.2 to 17.0 per
cent.; hydi-ogen, 6.9 to 7.3 per cent. ; and sulphm-, 0.3 to 2.0 per
cent.

Manifestation of Life. Wliile ehenncal examination has re-
vealed ver}^ little of the intimate natui'e of living matter, we
know certain properties to be essential to living matter as long
as it is really alive, and we know, also, some of its morphological
features, to as great an extent as direct observation is possil)le with
our l)est modern magnifying apparatus. The physiological proper-
ties are \dsible in every nio\dng and growing organism, and they
must be attributed to the minutest living particles as well as to
the whole organism. We consider living matter alive only so
long as it exhibits to us certain physiological properties ; when
motion and reproduction cease, it is dead. Life is evidently a
peculiar kind of motion of the molecules (plastidules) of living
matter, of a relatively short duration. A change of the motion
is disease ; cessation is death. The chemical changes of living
matter are different during life and death ; the former are mani-
fested by motion and reproduction, the latter by decomposition,
which means simplificatiou of the atomic construction. The
shape of living matter is changed by decomposition, but hy
preservation we succeed in retaining the shape of the substance,
which we know was once the seat of life, and microscopic
morphology is largely leased upon oliservation of deiid but pre-
served living matter.

Pt-operties of Living Matter. The physiological properties are
mainly two: motion and reproduction — viz., the capability of
producing its own kind. In speaking of the motion of li\dng
matter, we do not mean the motions to which everv substance is
subject, and of which light, heat, electricity, etc., are peculiar
manifestations. There are certain forms of motion dependent
on the contractility or irrital:)ility of living matter which do not
occur in inorganic bodies, nor in organic matter after it has
ceased to be alive. This kind of motion enables Hving matter to
work, at least to a certain limited degree, against the law of
gravity. It is controlled by complicated laws, which we term
the "will '' and the " spontaneity " of living matter. According to
M. Foster, the term " automatic motion" is preferable to " spon-
taneous," inasmuch as it does not necessarily carry with it the

ciKXEUM. ri,'(U'i:irrn-:s or i.ivisa matti:!!. iT)

idea of inv^ularity, and l)rars n(» i-ctVrciirc to a "will." This
motion is of two varieties: one leadinjij to ehanj^es of siiap*- — the
(tm(i'hi>i(l motiou ; the other to ehanjtj:e!< of place — loroitiofinii.
Botli kinds are due to a peeuliar structui-e of tlie liv-inj^- matter
in a certain sta«ie of its development, and will oecui)y us after-
ward. Ilci-e I will only mention that, in former times, locomo-
tion was considered as a characteristic quality of animals.
To-day we are aware that a trrcat many of the low forms of
vegetable life in different stages of development are endowed
■with h)comotion, apparently depending on a certain degi'ee of
indix'idual ^\'iU.

The proj)erty of producing its own kind is exclusively
possessed by living matter, and is also of two varieties, \dz. :
production for the benefit of the individual itself, with the result
of increase of size — f/roniJi ; and production of new individuals
— (jt lit ration. We kn<^w that every li\TJig body is originally
small ; the ovum of the largest animal is just perceptible to the
naked eye, but it increases In' taking up nourishing material
from without — it grows. After having reached a certain size it
does not grow larger, but only reproduces, renews the used-up
material, until at last it ceases to renew an\i;hing, and then
becomes what we term dead. To-day, scientists have arrived at
the conviction that the building-material of plants cannot be
essentially different from that of animals. With advancing
knowledge of natural philosophy, the boundaries between the
animal and vegetable kingdoms have more and more fafled away.
It is impossible, in many cases, to say exactly at which point of
development an organism is a plant or an animal.

It has been claimed that the only distinguishing character
between plants and animals is that the former feed on simple or
elementary inorganic material, while the latter take in organized
food ; but this opinion can hardly be maintained, inasmuch as it
is impossible to say how the lowest forms of animals are nourished
at all. We know, moreover, through Charles Darwin's researches,
that there are carnivorous plants.

Generation. The property of generation may be looked upon,
in accordance with E, Haeckel's definition, as a growth of the indi-
vidual beyond its indiWdual limits ; at least, every organism must
reach a certain degi'ee of development before it is fit for propa-
gation. It is known that among the lowest forms of organisms
propagation takes place Avithout sexual intercourse, whereas there
is a division of labor among the higher organisms. l)oth vegetable

16

GEXEBAL FliOVEBTIES OF LIVING MATTER.

and animal; in the former ease, one individual gives rise to a new
one ; in the latter, two individuals (male and fenuile) are required
to produce a third. It is known, furthermore, that the simplest
form of propagation is division, when one individual, after having
increased in size, splits into two organisms of smaller size. A
variety of this process is the " gemmation '" : c r/., a small bud,
growing fi'om the surface of the mother-])ody, becomes gradually
pedunculated, and at length separates by breaking of the pedicle,
and foi-ms anew indi\T:dual. Another variety is the " endogenous
formation," in which a lump originates and grows ^^'ithin the
mother-body, and is freed afterward through bursting or active
perforation of the mother. Essentially all these processes are the

Fig. 1. — Diagram of Gexeratiox.

The aeries A represents simple division. Tho body at first sliows a slight impression on the
periphery of the nucleus, a ; the impression becomes deeper on the nucleus and visible on the
body. (' ; the nucleus has separated into two nuclei, and tlie two halves of the body are connected
by a thin pedicle, c ; two new individuals have been formed by breaking of the pedicle, d.

The serits B represents the yeneration by ijemmation or exogenous formation. The body
projects a solid, homogeneous bud of living matter, a ; the bud is attached to the mother-
body by a broad pedicle, h ; the bud, by taking into its interior some liquid from witboat
became vacuoled, and is attaclied to the mother-body by a very thin pedicle, c ; the pedicle
has broken, and two new individuals are formed, the original bud having assumed the struct-
ure of the mother-bod.v, d.

The series C represents the generation by endo(jenovs fonnation. Tlie body exhibits by the
side of the nucleus a larger lump of living matter, growing from a small srranule. a ,- the lump
has grown larger and become attached to the wall of the mother-l)ody by a pedicle, at the
same time around the lump a space has formed, closed by a flat layer of living nuitter, b ; the
lump has become enlarged and supidied with vacuoles, c ; the lump, now of the structui-e
of the mother-body, has escaped through a perforation of the wall of the mother, rf.

dKXF.HM. I'uoi'i'.in ii:s or i.ivi.\<i mmikh. it

saiiu'. Jiiul the itiain form of ]tl•(»|».•^^^•lti(»^^ is always a division.
Even in tlu' most lii^lily (Icvt'lopcd mammals the embryo orij^inally
forms a i»art of the mother-body, and, after having grown, by
internal «;('mniation or endogenons production, up to a certain
size, separates from tlie vehicle, the womb, and represents a new
individual. (See Fij,'. 1.)

Kemak was the finst to draw attention to tiie three forms of
propagation, but he was not aware of their being materially
identical, though morphologically different, manifestations of one
and the same process.

There is a striking peculiarity a])()ut generation, viz. : the
resemblance of the newly formed })ody to the prodiicing organ-
isms, the parents. It is an easy matter to understand that both
indi\dduals will ))e aUke in a case of simple diN'ision, because both
formerly made one single body ; but how shall we explain the
remarkable fact that, in higher animals, the off'sjiring so closely
resembles the progenitors, though <tnly vin-y minute parts of
these — the ovum and the spermatozoids — contributed to give
rise to a new individual ?

The opinion ()f E. Hering, that organized matter is endowed
universally with an " unconscious memor}-," a function upon which
depends, besides the capacity of imagination, of thinking, of
habit, also nutrition and propagation, is not an available one. I
therefore take into consideration only the three modern hy-
potheses of Charles Darwin, Louis Elsberg, and Ernst Haeckel.
Darwin promulgated in 1868 the " Pro\dsional Hypothesis of
Pangenesis," which consists essentially in the assumption that
thi'ough all stages of development the li\nng cells or units of the
body thi-ow off small granules, or "gemmules," which accumulate
to form the sexual elements ; and all the cells of the body, there-
fore, participate indirectly in the new formation of organisms. In
1872, Elsl)erg published his theory of the " Regeneration or Pres-
ervation of the Plastidules." He lays down the proposition that
the germ of every living individual contains plastidules of all its
ancestors ; so that these are liodily regenerated in their offspring,
simply because bodily particles are preserved directly from gener-
ation to generation. In 187.'3, Haeckel announced the h\i3othesis
of the '' Perigenesis of the Plastidules,'' according to which, in
opposition to the opinions of Darwin and Elsberg. no regeneration
or preservation and transmission of plastidules takes place, but
only a transmission of motion through inheritance.

Among these theories, I confess that that of Elsberg seems

18 GENERAL PllOPERTIES OF LIVINd MATTER.

to me the iiK^st probal)le one, inasmuch as it tries to exphiiii why-
certain jn'operties of ancestors, even in the second or thii'd
generation, may re-appear ; why bodily and mental peculiarities
are directly transmitted from parents and grandparents to their
offspring. With this theory, which suggests a direct increase
of plastidules within a limited hulk of living matter, we may
readily understand why, with progressive development of a
species, a perfection takes place which leads to the production of
more and more advanced beings from relatively lower ancestors.
Haeckel's view can scarcely be supported so long as we know
that a change of niotion as function is always due to a material
cause, namely, change of molecules in quality and quantity. All
this is speculation only, though entirely legitimate as an attempt
to bridge over precij^ices which present insurmountable obstacles
to the passage of our intellect.

Historical SJtetch of tJie Hftahi of Lining Matter. In 1835,
Dujardin discovered a contractile substance common to low
animals, which he termed " sarcode," but he was far from the
knowledge that this substance exists in all animals, believing it
to be pecuKar to the lowest forms. After Schleiden, of Jena, in
1838, discovered the form-elements of plants, and proposed for
them the name of '' cells," Theodor Schwann, of Berlin, in 1839,
found a striking analogy l)etween the intimate structure of
vegetable and animal organisms, and asserted that the ** cells"
are the simplest constituent parts of all tissues of the animal
body as well as of the plant. In his opinion, each cell is a
vesicle composed of a transparent membrane, containing a
fluid in which is suspended a central solid body, the nucleus.
Schwann beheved that cells may originate in a substance, the
plasma, independently of former cells, and through the authority
of Johannes Miiller, who fuUy accepted Schwann's doctrine, this
became the leading one, so that even C. Rokitansky held at first
that the plasma of the l^lood may, under favora1)le circum-
stances, produce cells. It was the discovery of Rudolph Vir-
chow, in 1852, that the cells are really the seats of Hfe, and that
every cell must originate from a former cell: Oinuis celhda e
cellula. Virchow, however, adhered to Schwann's original idea
as to the construction of cells, although a very simple considera-
tion wiU show that this cannot be correct — viz., the consideration
of the fact that no living material is ever a fluid, but always
either a solid or a jelly-Uke, semi-fluid substance. The next
who advanced the cell-theory was Max Schultze, of Bonn. He

(iiiM'.KAL i'U()i'i:irni-:s of Livi.sa MAiTKit. id

showed, in iSfil, tliat cliiiii^es of foi'iii, locomotion, and division
arc inn)ossiblc to coi-pnsclcs surrounded l)y a resistant mcni-
hrane; he maintained tliat the smaUest individual elements of
orj^anisms arc lumps of a jelly-like matter endowed with life, for
which he proposed, for jiood reasons, in accordance with the
German hotanist, Iluyo von Mold, the tei-ni '' pi-()to])lasm." This
jelly-like substance is identical with Dujai-din's '"sarcode." Max
Schnltze was the first to announce that the liviiiu- matter of the
infusi(m-animalcules and that of the cells of all animals are one
and the same substance. The cell consists, according to this
ol)server's views, of a nunute particle of protoplasm, in which
there are imbedded the nucleus and gran ides. In the same year
(1861), E. Briicke, of Vienna, though accepting Max Schultze's
views, asserted that the inicleus is not an essential part of the
cell, as he knew of many living lumps without any nucleus.
Briicke defined the " cell," for which he also proposed the name
of "elementary organism," to be a structureless lump of pro-
toplasm ; though fully aware of the necessity of the existence of
some structure, as in every substance, he regarded the structure
of the cell as imperceptible to our senses. S. Strieker, in
accordance wdth Briicke, in 1868, explained that the (;eU is
nothing but a particle of structureless protoplasm, usually con-
taining granides, but that these granid.es are nat essential
characteristics. He especially examined the form-elements of
the ovula of frogs while studWug their development, and
obsei'ved in these elements hyaline flaps, which he took for pui*e
protoplasm, whereas the greater part of the protoplasm was
fiUed with granides, or particles of yoke. The fact that every
living lump is capable of taking in foreign minute corpuscles,
granules of carmine or aniline, for instance, from without, led
him to the conclusion that protoplasm, perhaps, is devoid of any
visible structure, while the \'isible granules are secondary prod-
ucts of the protoplasm, or foreign substances accidentally taken
into the interior of the protoplasmic lump. S. Strieker, in his
" Histology," discusses the question, " how large the lump of
protoplasm must be to be entitled to the name of ' cell,' " and
comes to the conclusion that we should call a living corpuscle a
^'eell" only when we perceive in it the properties of a living
organism — \dz., growth, motion, and reproduction. Lionel Beale
(1860), independently of Max Schultze's doctrine, announced sim-
ilar views, arriving, however, at conclusions qiute different froni
those of German biologists. Apparently his microscopes, al-

20 GENERAL PROPERTIES OF LIVING MATTER.

though magnifying very much, did not show him the details
within the protoplasm, and thus, judging especdaUy from carmine
staining, he asserted the nucleus to be living or " germinal "
matter, while a great deal of protoplasm was to him identical
with the basis-substance of connective tissue, and he termed this
the "formed material," designating by this term even the most
active tissues, the muscles, and nerves.

Since M. Schultze's proposal, the term "protoplasm" has
largely been used, and my own researches in 1872 began on the
basis of the cell doctrine, as understood at that time, viz. : that
each cell is a structureless lump of protoplasm.

Ill

THE ARRANGEMENT OF THE LIVING MATTER
IN "PROTOPLASM."*

THIS chapter was published in 1873, in German. Nine years
of continuous observation have corroborated all the facts
published, and I simply translate from the German what I said
in 1873.

Amalxp. On watching a slowly moving amoeba, obtained
from an infusion, with high amplifications of the microscope
(1000-1200 diam. immers.), we see the following : In the body
of the amoeba is imbedded a globular, homogeneous, pale gray
nucleus. This is surrounded by a narrow light rim, which is
traversed by delicate grayish threads. Many of these thi-eads,
often visible only temporarily, are conical ; all of them emanate
at their base from the nucleus, and have their point directed
toward the periphery of the amoeba. Each point blends wath one
of the gray granules scattered throughout the body of the
amoeba. Many of the gi-anules again are connected with their
neighboring granules by means of filaments, so as to convey the
impression that the amoeba is traversed by an extremely delicate
net-work, whose points of intersection are the granules. The
outer contour of the amoeba consists of a continuous thin layer
of a slightly shining substance, into which penetrate filaments
of the most peripheral granides.

* Untersuehungen iiber das Protoplasma. I. Bau des Protoplasmas. Sitz-
imgsber. der Kais. Akademie der Wissensehaften in Wieu. April, 1873.

22 THE ABRANGEMENT OF THE

Oil soiiu! anitt^ha^ during- tlie locomotioii the following obser-
vations can be made. Most favorable for this study are amoebaB
containing a certain number of foreign bodies. The droplet of
the infusion should not be taken too large, as a floating amoeba
changes its shape, but not its place. The creeping ])egins after
the amoeba, if little fluid be present, reaches the surface of the
covering-glass or the slide.

We notice that in a central portion of the body, near the
nucleus, the granules approach each other, slightly increasing in
size, and that foreign bodies accidentally present between them
are retained. At the periphery of the body corresponding to
the contracted portion, a bulging of a pale protrusion takes place
simultaneously; in this protrusion a delicate reticulum is, at
first, still recognizable. The more the protrusion bulges out, the
more it flattens on the surface of the glass, the more does the
reticulum fade, until there is left only a light, structiu'eless flap.
In a moment, the foreign bodies then rush into the hyaline flap,
followed by a floating of the granules of the protoplasm,* and
the body of the amoeba, including the nucleus, is dragged toward
the protruded portion, which, meanwhile, has re-assumed the
reticular structure ; in other words, the locomotion is accom-
plished.

In infusions over one week old we find in almost every
amoeba coarse, shining granules, in varying iiuml)er. The
nucleus of such an amoel^a, which I briefly call an old one, often,
instead of looking homogeneous, contains one or several minute
cavities — vacuoles. Such vacuoles sometimes appear in the body
of the amoeba, too, and each vacuole is seen bounded by a con-
tinuous thin layer of a shining substance. Not infrequently,
two vacuoles coalesce by the breaking of the thin separating
layer, and thus, at fii'st, an hour-glass shaped, later, a roundish
cavity, is established. The vacuoles may disappear, as a rule,
suddenly, and in their place the reticulum l)ecomes visible, just
as in the rest of the Ijody ; sometimes within a vacuole, one or
more granules are seen in aii oscillating motion.

Upon placing a di*op of glycerine at the edge of the covering-
glass, each amoeba contracts into a homogeneous, yellowish,
shining, and immovable lump the moment it is reached by the
glycerine. Here and there a small vacuole is perceptible in such

* W. Kuehne has already observed the floating of the granules in the
amoeba. Untersuchungen iiber das Protoplasma uud die Coutractilitaet.
Leipzig, 1864.

LI visa M.[iri:i! is ■' moron. .\sMr 23

;i liiitip. Sdiiic of the lumps rciiiiiiii in tlie sliai)e described;
most of tlu'in, however, iifter Ji few iiiiiiutes, j^Tadiially resiinu^
the granular condition with increase of their cii-cninfci-ence; at
the same time tliey become gloltnlai- and .luiiiii nucleated. Such
an ama'ba remains motionless.

In still older infnsions, amoeba> make their appearance which
are characterized by large size, slowness of locomotion, and the
property of pushing out radiating offshoots. Such amoeba^
are especially sensitive to the action of distilled water. By
placing a dro]) of distilled Avater at one edge of the covering-
glass, and draining off the infusion water from the opposite
edge, the folhnving observation was made: Instead of long,
radiating offshoots, broad and short flaps weri^ protruded, the
long offshoots already present were gradually retracted, and loco-
motion ceased. Slowly the amoeba assumed a blunt, polygonal
shape. In its body vacuoles appeared, at first small, gradually
largei" ; the nucleus became indistin(?t, and afterward completely
faded away. Some of the granules, with jerking movement,
united into lai-ger groups, while others were seen to float in larger
meshes. The more the number of such free granules increased,
the more the amoeba approached the globular shape. At the
same time, many small vacuoles coalesced into a single large one,
and a globular protrusion at the periphery of the l)ody resulted.
Both the protrusion and the body of the amoel)a were seen to be
inclosed by a continuous shining layer. Within the vacuole,
small granules moved about. In the meantime the jerking
motion of the groiiped granules had ceased, and the number of
the floating ones became considerably augmented.

This description of the appearances after addition of water is
taken from one amoeba ; but all amoebge of the radiating variety,
under similar circumstances, exhibited the same features.

Blood-corpuscles of the ('rfor-fish (Astacns). In a drop of
blood, transferred from a broken limb of a living fresh craw-fish
upon a slide, and covered with a covering-glass oiled on its edges,
we recognize the l)lood-corpuseles with moderate powers of the
microscope. E. Haeckel * found these corpuscles to be amo-boid.
Two kinds of such corpuscles are noticeable, \\z. : pale and finely
granular ones with nuclei, which are either large and pale or small
and coarsely granular; and, second, others having only coarse,
yellowish, very shining granules. The granules of the latter
kind, as a rule, encircle light spaces containing scanty granules.

* Ueber die Gewebe des Flusskrebses. Miiller's Archiv. 1857.

24 THE ABRANGEMENT OF THE

If at the ordinary temperature of the room we watch a pale
corpuscle, we recognize lig^ht offshoots slowly changing their
shapes, which protrude from the })eriphery of the coi'puscle, while
the groups of the granules in the jjrotoplasm are also changing
their shape and location. The latter changes consist in an alter-
nating accumulation and separation of the granides, or their
transformation into a delicate reticulum.

Almost every coarsely granular body shows under a high
amplification the following, in the course of from half tu one
hour : Each single granule at first represents a globular, yellow-
ish, very shining body, which is separated from its neighboring
granules by a light, narrow rim, and this rim is traversed by
rather indistinct delicate spokes, connecting each granule with
all its neighbors. Each granule continually changes its location,
the more noticeably the gi*eater the distances between the single
granules. At the same time, hyaline flaps begin to protrude fi-om
the periphery of the granular blood-corpuscle. Soon each gran-
ide becomes flattened, cup-shaped, and all of them are now seen
distinctly connected by gi'ay spokes. Meanwhile the circumfer-
ence of the whole body has enlarged. Next, in every single
granule there appear one central or two excentric vacuoles, which
by enlarging and coalescing hollow out the granide so as to make
it look like a single or double shell, or ring. Two or more hollow
granules suddenly coalesce and are transformed into a delicate
reticulum, to such an extent that in place of the former coarse
granules a pale, finely gi-anular protoplasm has made its appear-
ance. Inside of it a hollow body becomes visible, inclosed by a
relatively thick and scolloped shell, and containing several coarse
granules. Such a body, in accordance with our usual terminolog}^
must be called a nucleus.

The pale protoplasmic bodies come from coarsely granular
ones, continue for a time to change their shape ; the nucleus and
its gTanules (the nucleoli), on the contrary, from the moment
they have appeared, d<j not change.

Upon adding a one-half per cent, solution of chloride of gold
to a fresh specimen of blood, the liquid was transformed into a
finely granular coagulum. The pale protoplasmic l)odies had be-
come globidar, and the coarsely granidar transformed into many-
shaped masses, having in their interior a delicate reticulum
surrounded by a continuous layer. In both kinds the nuclei
remained coarsely gi*anular and coarsely reticidar. After one
hour, the solution of gold being drained off, and the specimen

i.ivixa M.\rri:i! /.v - I'ltoiori.ASMr 25

exposed to (lnylijj:ht, tlu' yellow, sliiniiij^- suhstaiiee wliieli pi-odiiees
the reticulum in the i)r(»t()i)l;isiu and its nucleus assumed a
vaolct coloi', while the su])stance within the meshes remained
nncolored. *

li/ood of fill' Xiirt (Triton J. In a dro}) of l)lood of the newt,
transferred to the glass slide and covered with a <'overing-glass
oiled on its edges, we can observe tlu' motion of the coloi-less
})h)od-corpuscles for hours at the temperature of the room. The
changes of shape result from a })rotrusion of light flaps and
granular offslioots of varying l)i-cadth, and sometimes of con-
siderable length, from the periphery of the protoi)lasmic l)ody.

Many finely granular l>odies exhi})it in their interior a con-
tinuous change of the grouping of the grannies. Especially
after addition of a one-half ])er cent, solution of chloride of
sodium, during the locomotions of the body, vacuoles arise, and
the inner surface of the wall of many vacuoles looks jagged, as
if beset with torn points. For moments the whole body is
vacuoled, the smallest, just percei)tible, vacuoles l)eing transitions
to still smaller meshes, the filaments of w'liich show pale gray
granules as points of intersection ; this appearance is only tem-
porary, as the next moment most, or even all, of the vacuoles
may have disappeared.

In fresh blood, some coarsely granular colorless blood-cor-
puscles distinctly show filaments emanating from the gi*anules.
With the assistance of an immersion-lens, Xo. 13 of Hartuack,
I became con\dnced that, during the locomotion of the corpuscle,
the single granules continually keep changing their size and
shape, as well as their location.

In the blood of newts which had been kept aU winter, the
nuclei of many colored blood-corpuscles were ^isil)le, ])oth imme-
diately after the mounting of the specimen and after it had
remained a time on the glass slide. Each nucleus exhibits a
number of coarse, very shining granules, some of which show
filaments that are united with the neigh])oring granules. The
nucleus is bordered by a continuous layer of a sul>stance of the
.same refraction and color as the granules. There is often seen
around the nucleus a very narrow light rim, which at times

* According to N. Lieberkiibn (Uebor Bewegungserseheiiiimgen der
Zelleu, 1870), in blood-corpuscles of many caterpillars thei'e exists a space
between the contractile layer and the nucleus which is traversed by fila-
ments extending from the inner surface of the contractile layer to the outer
surface of the nucleus.

26 THE ARBANGEMEM OF THE

looks traversed by delicate radiating spokes, lost to sight in the
colored portion of the blood-corpuscle.

The specimen shows numerous free bodies of the aspect of
nuclei of red blood-corpuscles, and the surface of many of such
bodies is beset with pointed, as if irregularly torn, filaments.
Besides, there are globular bodies in smaller number, which
decidedly surpass the size of these, though they are coarsely
granular, and inclosed 1)y a shell, like the nuclei. Neither of
these formations exhibited locomotion at the ordinary tem-
perature of the room.

Colorless Blood-Corpuscles of 2[an. I have transferred to the
heating stage my own Ijlood, which I took from a small prick of
the palmar surface of the thumb. No structure was recognizable
in the shining colorless corpuscles at the temperature of the
room. As soon, however, as the temperature of the specimen
reached about 30 deg. C. (86 deg. F.), the colorless T)lood-cor-
puscles — I mean the finely granular ones, resting in plasma
encircled by red blood-corpuscles — always exhibited the follow-
ing features :

In the center of the corpuscle one or tw^o gray, opaque, homo-
geneous lumps made their appearance. From every lump
emanate radiating conical spokes, which unite the two lumps,
when such exist, or wliich are directed toward the periphery of
the body and inosculate 's^•itll a net-work traversing the whole
corpuscle — a net- work the points of intersection of which appear
slightly thickened, in the shape of nodules, or granules. On the
periphery of the corpuscle the reticulum is inclosed by an

apparently continuous, somewhat
shining, layer. The central lump,
the spokes, and theii- nodides are
identical in their optical features,
v\ while the mesh-spaces gi^'e the im-
r i»ression of light, structm'eless

fields. (See Fig. 2.)
"J;' As the temperature of the speci-

men rises gradiuilly toward 35 deg.
=^^ C. (98 deg. F.), continuous changes

Fig. 2.-DIAGKAM of a Living ^>f ^^ape occur, both in the central
Colorless Blood-Corpuscle. lump and in the net-work of the

corpuscle. Simultaneously with
changes of the shape of the latter, a smaller or greater portion
of the central body at times is transformed into a reticulum,

i.nisc M.\iri:i; is •• I'h'ojoi'LAs.y." 27

while, ill tilt' rest (if the corjjiisclc, coarser «^r(tii]is (tf jiraiiiiles
arise, with either no iMesli-si»aees or else very narrow ones. Tlie
groups at times are dissolved, and re-ai)i)ear in different plaees,
and such altornatious <;ontinue even when the temperature is
gi'adually lowered.

In one eohn-less blood-eorpuscle (temperature 2-i.') dr<x. C,
73.6 detj. F.), a vaeuole made its appearance, in which a torn
o-ranule oscillated. I observed that the granule changed its
shape, and, at its periphery, delicate filaments appeared and
disappeared. On one occasion, three unusually long filaments

were thi'own out so as to I'cacli

^..-s^.j-.-.B,.^ the wall of the vacuole, where-

. upon the vacuole suddenly disap-

. ^ peared. Afterward, a new vacu-

( ole, containing a granule, pre-

_ T.^--OV seuted itself in nearly the same

^(^V"^/ !> place; but this vacuole became

^^5=^^^ dumb-beU shaped and enlarged

\ V / by the rupture of the wall of a

neighboring vacuole. StiQ later,

„ o Tx 17- the whole blood-corpuscle was

Fig. 3.— Diagramof aVacuoled ^^^ . i n i

Blood-Corpuscle. transmuted mto a vacuoled lump,

which continued to change its
shape, though very slowly. (See Fig. 3.)

In some blood-corpuscles, small, vesicular nuclei, with dark
contours, and constantly one or two
nucleoH, often arose at an ascending
temperature below^ 30 deg. C {S6 deg.
F.). Such nuclei, on raising the tem-
perature, originated in different places
of the coi"puscle, as I could dii-ectly
observe, from pale gray, compact
lumps, devoid of a dark contour. In
addition to the larger, distinctly boi--
dered nuclei, up to the nuniljcr of four,

I also met with a varving number of ^ , t^ „ . TA,,.r.

_-, - f ,. ... Fig. 4.— Diagram of a Dead

smaller nuclei. The nucleoh within a Blood-Corpuscle.

dark-contoiu*ed nucleus possess deli-
cate radiating spokes, which go to the boundary layer of the nu-
cleus. The boundary layer, invariably suiTOunded by a light
rim, sends off numerous spokes, and these inosculate with a net-
work traversing the whole corpuscle. (See Fig. 4.)

28 THE ARRANGEMENT OF THE

Blood-corpuscles in whicli nuclei of the above description had
originated, did not materially change their shape, even if the
temperature was raised up to 35 deg. C. (91 deg. F.) ; the only
noticeable change consisted in a temporary bulging from the
periphery of the corpuscle, of a hyaUne flap which slowdy increased
in size. In such a flap, no structure was perceptible, but some-
times very smaU vacuoles, which were invariably inclosed by a
somewhat denser, slightly shining substance.

Colostrum Corpuscles. The colostrum, as is well known, holds
a variable number of protoplasmic lumps, which sometimes
contain fat-granules, and, as first demonstrated Ijy 8. Strieker,*
upon raising the temperatui-e up to 40 deg. C. (104 deg. F.),
change their shape and location — therefore are alive. If we
look, T\'ith an amplification of an immersion-lens, No. 15 of
Hartnack, at a pale lump ever so small, which, with lower powers
appears to be structureless, we find in every one of them, even
though a nucleus be wanting, a reticulum identical with that of
a colorless blood-corpuscle. The points of intersection of the
reticulum are granules, either very small and pale gray, or
somewhat larger and glistening. Some granules exhibit the
pecuhar luster of fat, but are in connection mth the rest of the
corpuscle by means of delicate filaments. Larger di'oplets of fat
apparently lie isolated in the mesh-spaces. The author named
has proved that gTanules of fat may be discharged from the
protoplasma during its contractions.

In the foregoing, I have collected a number of facts, observ-
able by every one who has a well- versed eye and a good lens. I
now proceed to draw conclusions from my observations.

First, it is obvious that a reticulum in protoplasm, as con-
ceived but not seen by E. Briicket and S. Strieker, | is visible.
The protoplasm, therefore, is not structureless, but has a reticular
structure, and the granules are not foreign, but belong to living
protoplasm, being the points of intersection of the reticulum.

The N'ueleolus, the N'ucleus, and the Granules, with their Con-

* Ueber contractile Korper in der Milch der Wochnerin. Sitzungsber. der
Wiener Akad. d. Wissensch. 18G6.

t Ueber die sog. Molecularbewegiing in thierischen Zellen, iusonderheit
in den Speichelkorperchen. Sitzungsber. d. Wiener Akad. d. Wissensch.
1863.

t Untersuchungen uber das Leben der farblosen Blutkorperchen des
Menschen. Sitzungsber. d. Wiener Akad. d Wissensch. 1SG7.

I.IVlSa MAIl'Kli IS '' I'UOIOI'I.ASM:

'1\)

tu'cthuj FihiiiH'iifs, ((re t/ic Lirint/, or CoiilrtK/i/r M(tfftr Projxr.
This solid iiiiitter is susj»»Mid('(l in a ii(>n-li\iiig-, not contractile
lit|ui(l. In other words, flw confntrfi/r mutter in nicsh-sjKifcs ron-
fdinx <ni(I, ((s (t s/irll, incloses, t( iKni-eontntrtile Jhiid iii<iff<r. whicli
latter cannot be simple water, as the
phenomena of diffusion prove.

Startin<i' from the roiidition of rest
of the protoplasma as it ajjpears in a
colorless blood-corpuscle which has
just become dead, we may considei"
every granule as a central portion of
contractile matter, which connects
with that of its neighbors by means
of narrow bridges. (See Fig. 5.)

Contraction consists in an in-
crease of the size of the granules,
and their approachment to each
other. Hereby the filaments are ob-
viously shortened for the benefit of the granules. (See Fig. 6.)

Tetanus I will term the condition which I observed in
amoebae brought in contact with glycerine. It is caused by an
intense contraction of the living matter. (See Fig. 7.)

Fig. 5. — Diagram op Rest.

Fig. G. — Diagram of
Contraction.

Fig. 7. — Diagram of
Tetanus.

Extension, on the contrary, consists in a decrease of the size
of the granules until they almost disappear, with their simul-
taneous moving apart, and an elongation of the filaments at their
expense to apparent fading of the structure, as in the hyaline
flaps. (See Fig. 8.)

30 THE AliBANGEMEXT OF THE

111 additioii to these differences in the shape of liWiig matter,
I would mention the siveUed f/lohiile (Qiielluiigskugel). This shape
occurs under tlie influence of a liquid less concentrated than that
held in the protoplasma, as, for in-
stance, on addition of distilled water. p
Some authors have considered this as
the condition of rest. It is preceded
by a jerking of some groups of gran-
ules, without change of the general
shape of the protoplasmic body. At
the same time many granules are
torn asunder, and float about in the
mesh-spaces, which have become en-
larged by numerous ruptures.

Increase of the liquid in the proto-
plasm is accompanied by the/o/v«rtf/o// Yia. s.— Diagram of
of vacuoles. In the liquid contained in Extensiox.
the vacuole, granules torn off float

about, and may throw out filaments ; these filaments may extend
so far as to reach the waU of the vacuole. In such a case the
latter instantaneously disappears, and the former condition of
the net-work is reestabhshed.

Should the waU of a vacuole near the sui'face break in con-
sequence of an increasing tension, or that of the protoplasmic
body itself Ijreak, the protoplasmic liquid will escape in the first
instance ; while in the second, a piece of the protoplasmic body
may be torn off, the debris of which, to the minutest gi-anule, are
still viable. Or the whole reticulum may break down, and the
surrounding liquid, water, not favoring the life of the contract-
ile matter, deprives every particle of its life.

Analysis op the Assertions Made in 1873.

The reticulum in the "protoplasm" was seen and depicted by Nasmyth
(1839), in coi'puscles which to-day are known to be the covering epithelia of
the tooth ; by C. Frommann (1807) in "ganglion-cells," and by others in the
same and other corpuscles. What I have described, is a reticular structure
of the "protoplasm" as a universal occurrence, and my assertions have
since been corroborated by all good observers.

In 1877, I added the following remarks : *

* "The Cell Doctrine in the Light of Recent Investigations," JN'eu; York
Medical Journal, 1877.

I.niMi MAIIKI! IS •• I'UolOI'I.ASMr 31

•'Tlif t'tilly (k'Vflttpcil in'otopliismic body is foiistnictcil like a spoii^ic, hut,
at the same time, im-losed on all sidi's by tlic same Hubstanee which forms
the tnibeeiilu' of the s])on<,'e — the trabeeiihe anil tlie sliell l)ein}< the living
matter.

"An analysis of the observations of the livin;:; jji'otoplasmic body teaelies
us that there can be distiuffuished maiidy three <Ufferent appearanees of tlie
net-like living matter — namely, that of rest, that of active contraction, and
tliat of passive extension.

"In the state of rest, as seen in a motionless amreba, or immediately after
death, the granules are almost uniformly distributed throughout the pro-
toplasm, united witli each otlier by slender threads, the bridges of living
matter.

"In eoutraction, we observe an enlargement of the granules by shortening
of their uniting threads and approximation to each other. Xotliing has been
added to the living matter and nothing lost from it ; only tlie distribution of
tlie phistidules has changed, leading to the narrowing of the net-work, and a
partial expulsion of tlie fluid formerly contained in its meshes. Contraction
is tlie active property of living matter, and on it are based the simple change
of .shape and the h)coniotion of tlie whole organism.

" Extension depends upon a decrease of size of the gi-anules, with a
removal from each other and au elongation of the vmiting threads at the
expense of the bulk of the granules, even to the disappearance of all
structure. The extension takes i)lace in a passive manner ; the fluid con-
tained in the meshes of the living matter is pu-shed out toward the peripherj-,
and there leads to the formation of a protruding offshoot — the hyaline flap.
At the beginning of the protrusion we still observe in the flap the presence
of structure, while at the highest point of extension the structure can no
longer be seen, because gi-anules and threads have been elongated to their
utmost capability. We may compare this phenomenon to the extension of
glass rods, melted on a flame until the threads become so thin as to disap-
pear to the naked eye.

" These three states of liAing matter explain to us not only the movement
of a simi)lo protoplasmic lump, but also the action of the most highly developed
muscles, which, as I have demonstrated, are entii-ely identical in their
structure with the simple amoeba. Were the amoeba a sponge ^vithout an
inclosing layer of living matter on its surface, every contraction would lead
to au escape of the fluid, and no locomotion would be possible ; the pres-
ence of an outer, although very thin, layer of liWug matter is necessary to
the various movements of living protoplasmic bodies.

" By adding a drop of glycerine to the creeping amoeba, or to any pro-
toplasmic body, we can bring about a fourth state of li\-ing matter, viz.,
the highest degi-ee of contraction, for which S. Sti'icker and I have proposed
the term ' tetanus.' The fluid of the protoplasm being suddenly extracted
by the glycerine, all granules flow together, forming a structureless lump of
much smaller size than that of the original corpuscle, without ^^sible limits of
the single granules. A rehaliilitation of the former net-like structm-e is pro-
duced by taking awaj^ the glycerine and adding water, without reestablishment
of motion.

"All these changes of li\'ing matter can be directly seen under the
microscope. But we cannot observe the formation of a flat, extended layer

32 THE ARBANGEMENT OF THE

at the boundaries of the whole body, at those of a hollow nucleus and of every
vacuole. I therefore had to have recoiu-se to the liypothesis that a granule
may send out olfshoots in great number, leading to the disappearance of the
central mass, and that these offshoots, melted together, may produce a con-
tinuous layer. By the union of Tuany such areas an extensive layer could

be produced, large enough to cover in the
whole protoplasmic body. (See Fig. 9.)

"The presence of a layer of living sub-
stance on the outer surface of the body ex-
plains to us why every protoplasmic lump can
so easily take up foreign bodies, and why
vacuoles can form and disappear almost sud-
denly. We must imagine that the living
matter is capable of entering any of the de-
scribed states at any time, so that a flat
layer, for instance, may immediately change
into a net-work, and rice versd. When the
lump swells up through the adtlition of water,
the gi-anides are torn apart and float freely in
Fig. 9. — Diagram of the the fluid, as occurs in swelled amcebfe and
Flat Layer. saliva-cori^uscles. The breaking of the outer

shell, with escape of minute particles of the
amceba, still endowed with life, and the process of the di\asion, can also
easily be understood. . . .

"In conclusion, I may draw attention to the fact that the amount of
li^^ng matter varies greatly within a limited bulk of protoplasm, both in
normal and morbid conditions. The colorless blood-corpuscles of persons ex-
hibiting signs of lymphatic, strumous, scrofulous constitution, contain much
less living matter than those of strong, vigorous persons. Further examina-
tions will in all probability teach us to make use of these differences for
practical purposes. I announced three years ago that the protoplasmic lumps
forming tubercle are characterized by a relatively small amoimt of living
matter. Last year I published my observations on pus-corpuscles, which
enable me, fi-om the relative amount of living matter contained in an indi-
vidual corpuscle, to say from what kind of organism such a pus-corpuscle
is formed; whether the person from whom the pus comes is healthy and
strong, or weakened by chronic disease, as tuberculosis."

The idea of a structureless protoplasm was little satisfactory.
Since 1873 this structure is known to be reticular, tlioug-h the
reticulum itself, with all its nodulations , allows of no fui'ther
discrimination of structure. How complicated the reticular or
filamentary structure of the nucleus may be, is brought to evi-
dence by the researches of Auerbach, Flemming-, E. Van Beneden,
O. Hertwig, and others. The radiating: " suns" as they appear
in the process of division of the nucleus, the " Karyokinesis "
of Flemming, become explicable by the presence of a substance
able to gi"ow, to move, and to assume different shapes.

LI\L\(! MATTKR L\ '' J'UOTOl'LASM." 33

Onh/ (I rurt of J*n>fo}>](ist)i is Liriiif/ Mdffir. Tlu' main stress
is to 1)0 laid on my assertion tliat not tlic whole mass hitherto
termed protoi)lasm is endowed with properties of life, l)ut only
a part of it — the livinij^ matter j)roper. As I shall later on
demonstrate, the livinjif matter ap})ears first in the shape of a
solid, hoinoi«-eneous, ap})arently strnetureless <;ranule. wlii<']i by
ji^rowinji:, by taking in liquid, and ))y splitting into a retieulum,
becomes what has been termed protoplasm. Protoplasm^ there-
fore, is oiiJi/ one sfii(/(' i)i the (JcrcJopiiirHf of Jiriiif/ matter, and by
nt) means its exelusive api)earan<'e under the mi('ros('oi)e.

The two main properties of living matter, motion and
growth, are possessed by every, even the smallest, lump of living
matter. The motion is relatively little marked in a solid lump,
and becomes the more evident the more the living lump has split
up into a reticulum, the more it has assumed the ai)pearance of
*' protoplasm." Growth, on the contrary, is a marked property
of every granule of li\'ing matter; on the increase of its size
depends generation, formation of complicated organs and organ-
isms, and new formation, so striking in inflammation and in
tumors. All varieties of generation (see page 10) are due to
a motion and growth of the living matter, while the protoplasmic
liquid, probably nitrogenous too, a substance of secondary for-
mation, is a carrier of nutritive and used-up material of the li\dng
matter. The formation of basis and cement substance, and the
process of secretion, furnish direct proofs of the significance of
the protoplasmic liquid.

Chemical Re-agents. Verj'- little is known as to chemical tests
of living matter. Carmine solutions, as a rule, stain it, and
this explains why the nucleus, which holds a good deal more
living matter than the rest of protoplasm, is more deeply stained ;
the action of h^matoxylon (in alcohol specimens) is similar ;
chloride of gold renders living matter violet ; but neither are
absolutely rehable. Acids destroy living matter ; consequently
also acetic acid. The former method of bringing to view the
nucleus by treatment with acetic acid simply destroyed the rest,
due to the fact that the bidky formations of the nucleus resist
the action of acetic acid more than the scattered formations in
the protoplasm. This re-agent has scarcely any value. The dif-
ferent stainings of tissues l)y re-agents, especially combinations
of indigo, picric acid, and aniline colors, are caused by a differ-
ence of the chemical products of living matter, rather than by a
difference of the living matter itself.
3

34 ' THE AERAXGEMEXT OF THE

Analysis of Rest. Lh-ing matter, as long: as it is alive, can never
be at absolute rest, and in the protoplasm a uniform distribution
of the reticulum is not observable as long as motion is present.
The condition of comparative rest (Fig. 2) may be exhibited by a
portion of the protoplasm ; while another portion is in the con-
dition of contraction, another again is in that of extension. Rest
is death, and seen in motionless blood or pus corpuscles, which
on dying often assume the globular shape — viz., an accomplished
equilibrium of the reticulum. By evaporation of the liquid, even
such globular bodies may present a jagged, irregular shape,
which is not amoeboid, as erroneously has been asserted, but the
result of shrinkage. Death, however, may ensue at any moment
during coutracti(jn or extension, if the li\'ing matter be killed
instantaneously by a re-agent. Motionless pus-corpuscles — f. i.,
in urine — may be found in greatly varying amoeboid shapes, and
the peculiarities of the reticulum in the contracted and extended
condition remain fixed in such corpuscles if kept in ])reserving
fluids — f. i., solution of chromic acid.

Anah/sis of Contraction and Extension. Contraction of the
reticulum causes the amoeboid motion and the locomotion of a
protoplasmic mass. The liquid held in the meshes, being di-iven
out of the contracted portion, will rush into a portion at the time
at rest, and will extend this portion in the shape of what has
been termed pseudopodia. If contraction takes place in one half
of the protoplasmic mass, the other half will be in extension ; if
two peripheral segments be contracted, the intermediate portion
will be extended. The latter was suggested by Hermann, long
before the structm-e of protoplasm was known. In the former
instance a flap "SiTll protrude, nearly of the diameter of the body
itself ; in the latter a narrow offshoot, a ^' pseudopodium,'' will
make its appearance, var\dng in length, and exhibiting either an
indistinct structure or being apparently devoid of structure, on
account of the great sti-etching of the reticulum. To allow loco-
motion to be accomplished, the protruded flap must adhere to a
solid base, so as to have a point of fixation, toward which the
balance of the T)ody is dragged. An amoeba, a colorless l)lood-
corpuscle, can commence creeping only after one of the protruded
flaps has reached the upper surface of the slide or the lower
surface of the covering-glass, for the same reason that a man
can make a step only on a solid ground, and climl> only by
attaching himself with arms or legs to a support. The motion
of protoplasmic lumps is liveliest if the slide and cover be close

i.ivisd M.ir'i'hi; i.\ " Pii-o'ioi'LASM." 35

to t'iich other, ;ni(l \\u- inlcrvcniii^^ layt-r of liiiuid, tlicrcfon',
very small.

AtKilt/sis of Tt'faiins. Totiinic oontraction was first observed
l)y S. Strieker, in colorless hlood-eorpiiseles in lively motion, the
slide and eoverin^-<;lass being- elosely attached to each other, at
the moment when the cover was lifted a little by the addition of
an indifferent liqnid to the edfjc of the specimen. As soon as the
liipiid evaporated, motion and locomotion set in once more. I
have prodnced the same condition l)v the addition of glycerine.
Tetaniis is also ol)served in most of the colorless blood-corpuscles
and amoebae, immediately after their transportation to the slide,
evidently due to mechanical shock. Similar results were \delded
by the electric current. To call such a condition "rest," is cer-
tainly erroneous.

Anali/sis of Investing L(uiers. The production of a continuous
layer of living matter around the protoplasmic mass and a h(jllow
nucleus can be explained by a hypothesis only (Fig. 9). Such a
layer is far from being an investing membrane, in the sense of the
old cell theory ; it is identical in every respect with the reticulum
present within the protoplasm. Its capacity of admitting exten-
sion is surprisingly great. The thicker this wall is, either around
the nucleus or around the protoplasm, the less is the capacity of
producing amoeboid motion or locomotion. Solid nuclei and
nuclei with a broad investing shell do not themselves move,
but are carried along in a mechanical, passive way by the
moving reticulum around. Coarsely granular protoplasmic
bodies with a very marked investing layer do not move. The
finer the reticulum, respecting its points of intersection, and
the thinner the covering layer of li^dug matter, the more pro-
nounced is the capacity of amoeboid motion and locomotion.

The continuous layer of living matter may at any time and almost instan-
taneously be transformed into a reticulum. A foreign body may be taken
into the interior of a protoplasmic body by offshoots embracing the foreign
mass, the distal ends of the offshoots then coalescing, and lastly at the proxi-
mal ends, the investing layer being converted into a reticulum. The thinner
a flat layer, or the more it is stretched, the more prone is it to fuse together
with neighboring formations of the same kind. Long offshoots of amoebae, f. i.,
easily coalesce to form a coarse reticulum. Not all foreign bodies that are
taken into the interior of the amoeba can serve as a pabulum, as, f. i., carmine
or aniline granules, silicious shells of diatomes, etc.

The bursting of the outer investing layer is necessary for the
extrusion of foreign bodies, or fat-granules, or a liquid. Such a
wound at the periphery of the protoplasmic body may heal imme-

36 THE ARRANGEMENT OF THE

diately Ijy coalescence of the flat layer. Obviously, the bursting
must be due to a sudden and intense (-ontraction of the reticulum
close beliind, and as the foreifz^ii particles are often driven out
with a certain force, like a sliot, we may conclude that, together
with the foreign body, also a certain amount of liquid has escaped
from the interior. A momentary reestablishment of comparative
rest in the contracted portion would seem to 1)6 required for the
coalescence of the separated portions of the outer flat layer. A
part of the reticulum itself may penetrate the investing layer, or
a single granule Avith adhering filament. The result will be a
small protT'usion, or a single granule attached to the outer surface
by a slender pedicle.

Analysis of Vacuoles. A vacuole is a lake in the middle of the
protoplasmic body, inclosed by a continuous layer of living matter.
Without sucli an investing wall the lake could not ))e formed.
The vacuole may increase in size, either by stretching of the
encircling layer, or by confluence with a neighboring vacuole, if
the wall between the two should break. The vacuole may sud-
denly appear, and also suddenly disai)pear. Granules of living
matter are sometimes floating in the lake ; sometimes offshoots
of a granule reach the inner surface of the wall of the vacuole,
and the reticular structure is immediately reestablished. Vacu-
oles may be formed, and may disappear suddenly, in ways and
for reasons which we do not understand as yet. Formerly, the
vacuoles were thought to be stomachs of the protoplasm, an
assumption for which we have no ground whatever. Embryo-
logical research, on the contrary, proves that vacuoles are ele-
mentary vascular organs, containing plasma; as E. Klein first
demonstrated, the heart and the blood-vessels are originally
nothing else but vacuoles.

Comparison of Amceha and Man. The analysis of a single
protoplasmic lump is of the greatest importance, inasmuch as
such a lump is the simplest animal organism, on the plan of
which are Tniilt up all, even the most complicated organisms.
It will be demonstrated farther on that the human })ody is con-
structed on the plan of an amoeba, and the comparison wiU be
carried out in all details. Man is a cojnplex amoeba with per-
manent protrusions, the extremities, with a wonderfully compli-
cated division of labor of the groups of the living matter. Man,
in toto, is an individual, as is the amoeba, and in both, isolated
lumps of living matter float about — in the one case in vacuoles,
in the other in the blood and lymph vessels.

I.I visa M.[lli:i{ IS " I'L'OTOJ'LASM." ;{7

TllK StUICTI UK OK THK lil.(»()I)-(,'l»llinS('LKK OF TlIK (JYSTKK.

By a. M. Hi'iii.HiTT.*

Il" \vc lircjik tlic slicll of nil I'lilircly fresh oyster on its thinnest edge, a
siiiail (luaiitity of sea-water will ooze out. If we open the oyster by jdiUiiif;
apart the two valves, around the injured oyster a largo quantity of lluid
uoeuniulates. This fluid contains the blood-eorpuscles. P^irst we oil the
etlgi's of an extremely tliin cover on one side, place a small drop of the
juice of tlie oyster upoTi a slide, and cover it with the covering-glass, the
gi-eased edges looking toward the slide. We then have a speciTneu ready
for examination with the highest i)owers of the microscope.

A power of aV)out five hundred diameters will reveal numerous granules
floating in tlie fluid, in what has been termed molecular motion. These are
gi-anules of fat, of pigment, and of broken protoplasm. In the fluid there
are swimming very often parasites, whicli I do not wish to consider at this
time. Furthermore, debris of the tissues of the oyster and epithelia are to be
seen, and lastly, numerous gi*anular bodies, varying considerably in size
and form, and continually changing their shape or locality for at least two
hours. These are the blood-corpuscles of the oyster. Let us now put on a
lens with a magnifjang power of twelve hiindred. I used an immersion-
lens of Tolles, of Boston, and one of C. V^rick, of Paris, both maguif\ang
about twelve hundred diameters with a short eye-piece, and both giving the
same results as to the structure of the protoplasmic bodies.

We find globular bodies of the size of human red blood-corpuscles to be
considered as free nuclei, suspended in the fluid, and of which nuclei it is
impossible to say whether they exist as such in the live oyster, or are freed
by the injuring manipulation. Besides, spindle-shaped bodies are present,
not surpassing the nuclei in size. Lastly, protoplasmic bodies are visible,
varying in size fi-om one and a half to seven or eight diameters of a human
red blood-corpuscle, partly roundish, partly elongated in one or several direc-
tions, or stellate, — that is, provided with a number of delicate radiating off-
shoots. These protoplasmic bodies are in amoeboid motion, changing their
shape continuously by projecting flaps or elongated offshoots — the so-called
pseudopodia — on different parts of their perii>heries, and withdi*awing them
again. The changes of shape are not very lively — about as slow in character
as we observe them on the amoeba difluens, or in colorless blood-cor-
puscles of the newt. At the same time locomotion of the protoplasmic bodies
takes place, so that a corpuscle might migi-ate through the field of vision of
the microscope within one hour. On the fi'ee nuclei I tlid not observe changes
of shape or locomotion.

The blood-corpuscles are either devoid of a nucleus, or during the observa-
tion there may appear roundish bodies within the protoplasm, looking like
nuclei and disappearing again from om- view. Other corpuscles fi-om the very
beginning show fi'om pne to five or six nuclei. When nuclei are thus visible
at the beginning of the observation, they remain unchanged until the cor-
puscles in which they exist become motionless. In corpuscles in which no
constant nucleus can be made out, sometimes a nucleus becomes \"isible when
the corpuscle approaches the time of its death — that is, when it becomes
motionless.

Let us now watch a corpuscle in which a nucleus is plainly marked, and

* Xcw York Medical Joiiniaf, January, 1879.

38 THE ARRANGEMENT OF THE

we shall see as follows : The nucleus is surrounded by a yellowish shining
shell, which either is uniform in its width or looks Vjeaded, as if built up by a
number of granules, which are connected with each other by a thinner layer
of the same substance of which they themselves are composed. Within the
nucleiis we again find gi'anules, either uniform in size or some appearing to
be considerably larger than others ; these latter bear the name of nucleoli.
The granules vary greatly in number, and are either scattered irregularly
throughout the nucleus or are an-anged in the shape of wreaths, concentrical
with the outer shell of the nucleus. Sometimes two or even three of such
wreaths are to be observed within the nucleus, a fact to which Th. Eimer first
drew attention. In small nuclei we observe sometimes only one central
granule (nucleolus), and from this gi'anule there jiroject fine threads, from
three to six in number, conical in shape, the bases of the cones arising from
the granules, their thin ends tending toward the wall of the nucleus, with
which all the cone-like threads are invariably in direct union. Thus a wheel-
like figure is constructed, the hub of which is represented by the central
gi'anule (nucleolus), the spokes by the conical tlu-eads, and the felloes by
the shell or outer layer of the nucleus, the latter representing only the
optical section of the surrounding layer of the spheroidal body. All the
described formations are suspended in a pale, colorless, and structiu'eless
substance, between which and the fluid part of the blood outside the
corpuscles no distinction can be drawn. When there are several gramiles
present in the nucleus, all are joined together by means of fine, grayish
threads, the granules thus representing the points of intersection of a net-
work which traverses the whole interior of the nucleus. The granules next
to the wall of the nucleus — it is immaterial whether regulai'ly or irregulai"ly
placed — send delicate grayish threads toward the wall of the nucleus, with
wliich they inosculate. The meshes of the net-work within the nucleus, filled
with the homogeneous colorless substance, vary in size. I, however, was not
able to decide whether, during the motions of the whole corpuscle, there
were also changes in the shape of the net-work of the nucleus, which S.
Strieker asserts he has noticed in the net-work of the nuclei of the colorless
blood-corpuscles of the frog and newt.

The structure of the nuclei, as jiist described, is visible on all nuclei, no
matter how many may be seen within a protoplasmic body, and also on bodies
floating in the fluid specimen which were described before as fi-ee nuclei. In
none of the latter could I ever discover changes of shape or active locomotion.
Not very rarely, however, we meet with small nuclei in the blood-corpuscles,
which look almost homogeneous and of a pale, grayish-yellow color, appar-
ently devoid of structure. Such nuclei, which we might consider as some-
what larger granules, are also suspended in the outside fluid part of the blood,
as well as in the protoplasmic bodies.

Whenever a nucleus is to be seen in a protoplasmic body, outside its shell
a light seam can be observed, always traversed by conical, radiating thi-eads,
which spring by their broad bases from the shell of the nucleus, and unite by
their thin ends with the granules next to the light seam. Such conical off-
shoots arise also from compact nuclei, thus giving them the appearance of
angular bodies. Throughout the whole protoplasm gi-anules of different sizes
ai'e scattered, all of which show the same color and the same power of refract-
ing the Light as those within the nuclei. These granules are united with each
other by slender threads in the same manner as those in the nuclei. Very

LIVING MATTE U IX '' I'Jx'OTOPLASM.''^ 39

often the api)earanci' is presented of a single granule surrounded by wreaths
of other gi-anules, all the latter being united, by means of radiating conical
threads, both to the central gi-anule and to each other. Such small, wheel-
like bodies may arise in different i)laces in the protoplasmic body during its
changes of shai)e. Besides the gi-ayish-yellow granules, there are numerous
others of a more yellow color and of a gi-eater refi-acting power, identical with
that of fat-gi-anules. Experience shows that such fat-gi-anules are more
numerous in the latter part of the breeding season of the oyster — viz., in
Jidy and August. Many of these fat-gi-anules are connected by means of
delicate threads with the neighltoring ])rotoplasmic gi-anules.

During the changes of shape of the blood-corpuscle, round spaces often
aj>pear in the protoplasmic bodies, the so-called vacuoles. These vacuoles
vary gi-eatly in size ; they are filled with the light, structureless fluid sub-
stance which we see within and without the meshes of the net-work. In the
fluid of the vacuoles sometimes there are gi-anules floating about. Each
vacuole is suiTOunded by an extremely thin grayish-yellow layer, which is
always in union, l)y means of delicate threads, with the neighboring gi-anules
of the protoplasm. Sometimes several vacuoles arise within the corpuscle,
and are separated fi-om each other by a continuous layer, like the shells of a
nucleus, and these shells give the appearance of a frame-work. The same
appearance of vacuoles, though on a considerably smaller scale, I have
repeatedly observed also on nuclei originally homogeneous and structureless-
looking.

A continuous, though extremely thin, layer can be seen on the periphery
of and closing in the protoplasmic body. The outer surface of this layer looks
smooth, while its inner surface is in connection with the neighboring graniiles
by means of delicate threads.

While we watch a blood-corpuscle of the oyster at the common tempera-
ture of the room, continuous changes of its shape are visible, as mentioned
above. At the same time, changes of the net-work within take place. Tem-
porarily, the gi-anules seem gi-ouped together and the meshes considerably nar-
rowed ; opposite to such a gi'oup of closely packed granules flaps bulge out from
the periphery of the protoplasmic body. Within a flap there is faintly visible
a net-work only at the beginning of its protrusion ; very soon this net-work is
completely lost to sight, and the flap looks homogeneous, and apparently
structui-eless. At other times, delicate naiTow hyaline offshoots are projected
from the periphery of the blood-corpuscle, varying in number, and sometimes
considerably surpassing in length the diameter of the ijrotoplasmic body.
These so-called false legs (pseudopodia), as a rule, look homogeneous, and
run either in a straight direction or are curved and repeatedly bent. They
are being projected and withdi-awn fi-equently diiring the changes of shape of
the corpuscle ; sometimes they are thrown out so regularly, and in so gi'eat a
number, that the corpuscle assumes a beautiful star-shape, the central body
at this time being considerably decreased in size and its granules closely
packed together. The offshoots may also be irregular, and the blood-
corpuscle may take on a considerably elongated, iiTegularly angular, and
branching shape. On the thicker parts of the offshoots the net-like
structure of the protoplasm is to be seen, while their ends always look
hyaline and structureless.

Dui'ing the changes of shape, sometimes a number of granules melt
together, thus producing the appearance of a temporary nucleus; such a

40 THE ARRANGEMENT OF THE

nucleus, after a few minutes, may disappear again, and a net-work be
reestablished, where shortly before there was a compact lump. Sometimes
round bodies looking like nuclei jump forth fi"om the interior of the blood-
corpuscle, and float freely in the surrounding fluid. Sometimes protruded
flaps become pediculated, and shortly afterward, tkrough breakage of the
pedicle, a pale body is separated from the original blood-corpuscle. Some-
times the protoplasmic body itself is becoming constricted on different parts
of its bxilk, and such constrictions may terminate in a separation of smaller
lumps fi'om the original body. On some of these limips, even the net-like
sti'ucture of the protoplasm is still xdsible. Thus a larger blood-corpuscle
may be di^-ided into smaller lumps of dififerent shapes.

After from one to two hours' observation, the majority of the blood-
corpuscles, in part considerably decreased in size through repeated divisions,
swell up and are pro\'ided with large vacuoles and large, structureless flaps.
In this condition the net-work in the protoplasm is evidently broken apart,
inasmuch as the granules are no longer connected with each other, but float
in the interior of the protoplasm m a sort of motion, for which the term
"molecular motion" has been adopted. Lastly, such a swelled protoplasmic
body biu'sts, and the granules are spread in the siurounding fluid, and with
this complete death of the blood-corpuscle has ensued. Blood-coi-puscles of
perfectly fresh oysters die after having been kept for about two hours under
the microscope, whereas those fi'om oysters which have been kept out of the
sea for a couple of days die much sooner and more rapidly.

The Structure axd Growth of Some Forms of Mildew. By William
Hassloch, M. D., of New York.*

During researches in which I stained the corneas of dogs and cats with
chloride of gold, many of my preparations became mouldy, and, as repeated
application of the chloride produced well-marked characteristic violet colora-
tion of the mildew, I succeeded in studj-ing its intimate structure.

The application of one-half per cent, solution of chloride of gold, for
from one to six hours, sufficed to stain the parasitic growth fi-om a light-red
violet to a dark blue. The preparations were mounted in the common way,
in a mixture of distilled water with glycerine, and remained unchanged for
months.

"With a magnifj-ing power of ."JOO, thallus-threads (myeelia), hyphas, and
conidia coidd be seen, as well as numerous branching chains of conidia, all
united with myeelia. These formations appear finely granular. Many of the
granules are not round, b\it look jagged and pointed ; moreover, both the
hyphas and mycelia-threads show, on their periphery, accumulations of
minute, generally dark %'iolet, partly pediculated granules, to such an extent
as to conceal, in some places, the contom-s of the plant. For greater ampli-
fication I used an immersion-lens of ToUes, with a power of 1200 diameters,
and immersion-lenses of V^rick. With these the myeelia, mostly uncham-

* Xeic York Medical JounuiJ, November, IS 78.

LIVING MATTKU IN '' riiOTOPrASM." 41

berod, show thin, (hirk-viok't cdf^os, and coiitaiii a hirj^o Tiurnbcr of {^•aiiuh's
of difftMHMit sizes, which, aiiiiost without oxc'<<])ti()ii, am united by fine, viohft
tlireads. This urnin^i'intMit produces an exccediiif,dy delicate, violet net-work
in the interior of the niyceliuin-tliread, the meshes of which are either
uncolored or only slij^htly violet. The smallest {j^anules are homogeneous,
while the larger ones sometimes contain central spaces, vacuoles, which
appear in the optical section as small rings. Occasioiuilly larger vacuoles
are seen within the mycelium, each surrounded by a wreath of violet
granules. Not only are the majority of the granules connected with each
other, but threads pass also from the wall of the mycelium to neighbor-
ing granules. Wliere hyphro grow from the mycelium, the wall of the
latter looks as if perforated, but its outer contour is continuous with
that of the hypha^

The hyplue, always of less diameter than the mycelia, are more finely
gi-anulated ; but there is no doubt that their gi-anules are also connected by
exceedingly delicate threads, both among each other and the wall. The
majority of the hypha^ are covered with fine graimles, occasionally accumu-
lating in gi"oups, either attaclied with a broad base or by means of a minute
stem. Sometimes such a little body, or such gi'oups, may be seen coimected
by fine threads with gi'anules in the interior of the hyphaj. Just as in the
mycelium, we find also in the hyphaj a number of round or oval vacuoles,
which, uncolored themselves, are surrounded by a violet outline, or by a
wreath of gi'anules.

Many hyphie terminate in spherical or oblong conidia. Often a second
conidium is directly attached to the terminal one, or by means of an inter-
vening hypha. From this may proceed again a hypha, ending in a conidium,
and so on, frequently repeated.

The conidia are of two kinds — viz., thin-walled, the walls of which do
not sm-pass those of the hypha? ; or thick-walled, with a relatively broad
shell, interrupted only at the union with the hyphae or an attached conidium.
When two or more conidia are near together, that next to the hypha has
usually thin walls, while the succeeding ones have markedly thicker walls.
Both kinds contain granules, which, without exception, are connected among
each other and the conidium-wall, here and there being provided with vacu-
oles. The smaller of the vacuoles are ungranulated, while the lai'ger contain
either single granules or groups of granules, with filamentous connections in
all directions. ^V^leIl two conidia are directly attached to each other, the
place of union is broad enough to allow of a dii-ect connection of the granules
of both conidia.

The thin-walled conidia possess lateral or polar shoots, in the form of
sessile or pediculated gi'ainiles, or of projections of varying lengths, covered
with fine gi'anules. The structure of these projections is either homogeneous
or reticular. In thick-walled conidia I have never met with such shoots ; here
the homogeneous, shining shell is always smooth on the outside.

Many hypha; terminate in simple or compound conidia-chains. These
arise with the formation of successive notches, with increasing diameter of
the hypha. Such chains are mainly formed by thin-walled conidia, with
numerous, either granular or prolonged, buds. These buds not seldom appear
dark violet on their ends, while the stem near the conidia is uncolored. There
is either an iuteiTuption in the wall of the conidium, or a direct connection of
the stem of the bud with granules in the interior. (See Fig. 10.)

42

THE ARRAXGEMEXT OF THE

To obviate the suspicion that these appearances were produced, at least
in part, artifieiaUy, fresh mould was examined in an indiflferent medium, such
as bichromate of potash, aiid a complete con-espondence with what chloride
of gold showed was found, althou»h in a less marked degree ; so that I would

^^^^^.

Fig. 10. — Mildew Staixed with one-half per cent. Solution
OF Chlop.ide of Gold.

a a. threads of mycelium ; b h, hyphip ; c c, conitUa : d il, chains of conidia. Granolar buds are
visihlc on all hyphae and chains of conidia, while buds are missing altogetlier on thick-
■waUed conidia, cc. At ee conical buds or projections are present, the thicker ends of
■which are compact and staine<l dark violet, while .their stems appear Ught. Magnified
1200 diameters.

assert that only those who have studied the chloride of gold preparation
previously will find the fine threads connecting the granules in a fresh
preparation.

I have also examined several kinds of oidium, of which the close rela-
tionship among each other, as well as with the spores of mildew, has been
repeatedly demonstrated by other observers.

The structure of beer-yeast is identical, both in the fresh condition and
after staining with chloride of gold, only in the latter case the appearances
are more marked than in the former. In fresh preparations, free granules of
various sizes are recognized, of which some are at the limit of the visible,
even with an amplification of 1200, and groups composed of numerous
homogeneous, yellowish, shining, apparently structureless granules, which
are connected with each other by extremely delicate threads. The latter
are not yellow, but gray. Some granules have fine offshoots, the con-

T.TVixa ^f^rTl':n rx '^ j'L'ororrAs.v."

43

nj €/

Fig. 1 1 . — OiDiUM of Yeast.

a, hoiUKgoiieous fp-anulcs, partly
isolated, partlj- in shape of cliaius ;
6, oitlia with larfre vacuoles, whose
walls arc either coiiipa<-t or gran-
uhir, or traversed by minute vacu-
oles ; c, oidium devoid of a vacuole,
Its living matter in net-like ar-
rangement, the points of intersec-
tion being the granules. Magnified
1200 diameters.

nectinj; bridges bi'iiif^ no Uirif^cr visililc, even with tlie j^reatest iriaf^iifyiiig

powers.

Tile essential oidiii of yeust are, as is well known, mainly oblong

bodies, the majority of which contain a large central vacuole. High ampli-

lication shows that the outer shell represents
a usually homogeneous shining, yellow ring,
thickened at one pole of the oidium. Within
the shell, granules are ])resent, each of which
is separated from the other contents by a light
seam, and connected with the shell by minute
threads. The siu'faee toward the vacuole is
either smooth or covered Vjy granules, a part
of which projects into the vacuole. The thick-
ened portion of the shell is not seldom per-
forated by smaller vacuoles, each surrounded
by a layer of the yellowish, shining substance.
In the interior of the vacuole, isolated minute
granules may be found in active motion, while
smaller vacuoles contain a varying number of
gi'anules, connected among each other and with
the shell by finest filaments. (See Fig. 11.)

Oidia vrithout vacuoles have always a rela-
tively thin shell, and contain a number of
granules of different sizes, which, without ex-
ception, ai*e united. Only the yellowish, shin-
ing substance of the shell and the granules

become dark violet from the solution of chloride of gold ; all other parts

remain uncolored, or, at most, become only pale violet.

In fcrmentitKi wine, I met with a great number of small, free granules,

with short, rod-like formations (bacteria), and the round or oblong oidia.

Numerous oidia form chains of two or more members, the single links of

which are united by short, broad

bridges. Occasionally a small bud

is attached tlirectly, with a broad

basis, to a larger oidium. High

magnifying power shows that here

vacuoles are less numerous, and

of markecUy smaller size, than in

beer-yeast. Each oidium is bounded

by a yelloAvish, shining shell, per-
forated only at the union with its

neighboring oidia, and containing

in its interior a varjing number of

granules of different sizes, all con-
nected by delicate threads. The

granules show the same refraction

and color as the shell, while the

threads between the single gi'an-
ules and the different oidia are colored gray. Smaller buds and smaller

isolated oidia are almost always compact, yellowish, shining, and apparently

without structirre. (See Fig. 12.)

Fig. 12. — OiDirM of
Wine.

Fermenting

a, isolated oidia; b h, oidia in chain-like con-
nection. In all these the living matter is arranged
net-like ; the shell, being also a formation of living
matter, looks homogeneous, and is perforated
where the uniting bridges inosculate. Magnified
1200 diameters.

44

THE ARRANGEMENT OF THE

Fig

A

13. — OiDiuM OP Thrush from
Child's Mouth, after being
KEPT FOR Forty-eight Hours
IN THE Moist Chamber.

The grayish-wliite patches occurring in the mouths of infants, known as
fliriish, contain beside epithelia the following: Very delicate granules in
active, dancing motion — micrococci; short, single or double oscillating rods
— bactaria ; delicate threads, straight or variously curved, smooth or granu-
lar, and in the latter case occurring in
chains, mostly without movement —
lejitothrix ; and finally oidia. After
being kept for forty-eight hours in a
moist chamber, the mass removed from
the mouth shows a number of delicate
mycelia, the hyphae of which have small
sporangia. This vegetation is perfectly
identical with that of mildew. The oidia
correspond in their size to those of wine ;
many contain large vacuoles, in all de-
tails like those obtained from beer and
wine, only the color of the shell and the
granules is more gi'ay and very slightly
yellowish. In preparations kept for
forty-eight hours in a moist chamber,
many oidia are united in chains, and
many show prolongations, the extreme
ends of which are always compact and
structureless.* (See Fig. 18.)
Finally, I have seen in the oidia of acid urine, kept quiet for several days,
a structure perfectly identical with that of the mentioned various oidia.

From the description of different forms of the mildew, it is clear that its
intimate structure is perfectly analogous to that of animal protoplasm, as it
was first described by C. Heitzmann. This investigator, from his observations
of the phenomena of motion and growth of animal protoplasm, has arrived
at the conclusion that there are two kinds of constituent substances in it, —
viz., first, a gray or yellowish substance, which forms the limiting layer or
shell of the protoplasmic body, the granules, the central nucleus, and all the
connecting threads — the living matter ; and, secondly, a liquid not possessed
of life, which fills the vacuoles and the meshes between the net-work of the
living matter — the protoplasmic liquid.

Only the living matter becomes easily and distinctly violet when the prep-
aration is stained with a solution of chloride of gold.

The net-like structure is plainly marked in the low vegetable organisms

a, oidia with vacuole.^, with formation of
granules in the latter ; within tlio vacuole
single granules, with thread-like connec-
tions to the wall: '', oidinni, willi net-like
arrangement of the living matter ; c, chain
of oidia in budding ; the bud is compact,
liomogeneous ; behind this are links with
successively larger vacuoles. Magnified
1200 diameter.s.

* The fungus of the thrush recently has been studied also by Paul (Jrawitz (" Zur Bo-
tanik des Soors undder Derniatomykosen," T/. Zcltscltr. f. prakt. 3Iedicin, 1877). He made
experiments of raising, in transparent, nourishing fliiiils, and found in fluids rich with sugar,
after tweuty-four hours, iustea<l of single round ipr olilong coiiidia, clusters of oidia in budding
process. The more sugar was jprescnt in th(^ nourishing fluid, the denser and less tiaus-
parentwere the colonies of the oidia, while in fluids containing less sugar the dumb-bell
shapes of the oidia were prevalent. In the latter tiuid there occurred chains of oidia, on the
uniting bridges of which numerous grape-like buds weie visible. In fluids with a small quan-
tity of sugar and salt, pediculated buds grew in several directions from the periphery of
oblong oidia, and in one main dii-ection links sprang from the mother body, lastly forming a
chain-like thread. The oidia of the thrush, as raised in a fluid rich with sugar, produced, if
transported into a dilute finid, thin mycelia of the same shape in which we see them in fresh
thrush. Grawitz holds that the fungus of the thrush is in no relation to the oidiuin of milk,
but rather identical with the mycoderma vini. first described by Cienkowski.

JJVIXa MATTER IN '' I'h'OTOl'LASM." 45

tlescribiHl. Hero, too, tlu' yoUowish, sliiiiiiitj suhstiinco, f^'ay in tliin layers,
which is easily stained violet with ehloride of mM, forms a wall or shell of
varying; thiekness, the ^rannU's and eonneetinj^ threads; while the vacuoles
and meshes are tilled with a liquid which not seldom contains isolated
grannies.

('. lleitzniann declares that living matter presents at first a compact,
homogeneous little lump ; that this matter, on growing, is differentiated by
the formation of vacuoles into a frame-work, which includes the licjuid, not
endowed with life ; that, finally, at a certain degree of giowth, the differentia-
tion of a net-work takes place, the meshes of which contain the not living
fluid. These stages are demonstrable also in gi-owing mildew and oidia. The
first visible form-elements are homogeneous gi-amdes, and the fii'st appearing
buds are compact little projections, either globular or prolonged. The first
differentiation consists in the occurrence of a central vacuole, and only after
a certain development has been attained does the protoplasm appear in the
form of a net-work.

That the yellowish or gray substance is in fact the living matter, is
proved by the formation of buds on the hypha?, conidia, and oidia, and the
conidia-chains. The minutest l)uds are, in every instance, ilii-ect prolongations
of the shell, or a granule contained in the interior.

IV

THE PHASES OF DEVELOPMENT OF
LIVING JVIATTER.*

THIS article is a translation of a publication in German in
1873. What at that time were considered to be phases of
life of the protoplasm, must to-day be taken as different phases
in the develoj)ment of Ii\dng matter, one of which is its retic-
ular arrangement in protoplasm. This latter term, then, in the
present view, is applicable to only oup of the phases of devel-
opment.

AtnoeJxe. In sj^ecimens taken from an infusion on the third or
fourth day after its preparation, we meet with a few lumps of
protoplasm, not over 0.008 mm. in size, in slow locomotion. These
lumps are shining, yellowish, and formed by a very dense reticu-
lum of living matter ; some of them contain vacuoles. A nucleus
is not recognizable in such a youthful amoeba. A few days later
on, besides amoebas of the described size, others are found which
are larger, finely granular, and execute Hvely changes of shape
and locomotion. Every one of these amcebae has a pale gray,
homogeneous nucleus.

Specimens taken from the infusion in the third or fourth
week contain, in addition to younger forms, many amcebfe, with a
varying number of coarse, shining, yellowish granules. These are

* Untersuchimgen uber das Protoplasma. III. Die Lebensphaseu des
Protoplasmas. Sitzungsber. der Akademie der Wissenseh. in Wien. June,
1873.

DEVKLOl'MKM OF LIVINd MATTER. 47

either scattered tliroujjch the hody of the ani<jL'))a, or accumulated
in f,n-()ui>s, hut litth' exceedingly in size that of the nucleus. Both
kinds of <;raiiules are connected, l)y UK'ans of delicate filaments,
with the reticulum of the living matter of the lump. The pale
^•ay uuclei of sucli older amoeba? always exhibit vacuoles.

If we add a drop of f>-lycerine, diluted with one-half water, to
a specinuMi containinji; am(e})a' of early formation, each amfje])a
will, the moment it is reached by the glycerine, suddenly contract
into a homo^-eneous, yellowish, very shining lump, the size of
which is only a small fraction of its former circumference, or the
amoeba shrivels to a scolloped lump, which by the bursting of
peripheral vacuoles becomes in a few seconds nearly homo-
geneous. Such lumps remain, as a rule, unchanged.

Ama^l)a^ of a later period do not react uniformly to glycerine.
If both a finely and coarsely granular amoeba should be present
in the field of vision, the latter, on addition of glycerine, will
rapidly be transformed into a homogeneous lump, while the
former will slowly shrivel, sometimes only become corrugated
on its surface, and retain its finely granular character, becom-
ing, however, motionless and globular. Most of the lumps,
sprung from coarsely granular amoebcP, enter the globular con-
dition slowly. Some even remain unchanged. Whether this
difference is due to difference of concentration of the glycerine
which reaches different amoebse, even in one field of vision, I
am unable to decide.

By draining off the glycerine and replacing it with water,
all lumps are gi-aduaLly transformed into globules, but none of
them recover mobility.

The series of changes which the coarse granules of the blood-
corpuscles of craw-fish undergo, without the addition of any re-
agent, are described in Chapter II., page 23. An originally
solid, homogeneous lump of living matter, in a short time,
under our very eyes, becomes at first vacuoled, and at length
transformed into a delicate reticulum.

Cartilage-corpuscles. In comparing the corpuscles of cartilage
of mammals (I have examined the cartilage of the knee-joints of
dogs, cats, and rabbits) of different age, marked differences are
observed, dependent on the age of the animal.

The cartilage cavities of a pup, five days old, hold proto-
plasmic bodies, the nuclei of which are homogeneous, yellowish,
and very shining, and sometimes contain vacuoles. Besides,
there are mmierous smaller cavities entirely filled with a mass,

48

THE PHASES OF

in every particular like the nuclei of the cartilage-corpuscles
mentioned before. (See Fig. 14.)

When the solid substance forms the nucleus of a proto-
plasmic body, conical spokes arise from its peripher\^, which

blend with the reticulum of the

"^~ " protoplasm. "VMien the solid

substance alone fills the ca\'ity,

A —-^-^- the syjokes traverse the light

'""-'^ "^S" — ^~ "^ rim between its peripherj^ and

'-"■'^■^^r^' the border of the basis-sub-

..^ 'I stance of the cartilage.

5^-1^ , ^ In the cartilage of a pup,

^ — ~~ ' -:;:-r->-:0 six weeks old, ca\aties are

found whif^-h contain granular
pr<7toplasm, and lumps of a
homogeneous, yellowish, shin-
ing substance, variously dis-
tributed. (See Fig. 15.) There
are some cartilage-corpuscles
with a central soUd mass of the
shining substance ; other cor-
puscles with several solid lumps of different size : lastly, corpuscles
in which the shining substance ajjpears as an incomplete shell, in
the optical diameter as a semi-lunar ledge. Cavdties fiUed with the

Fig. l-i.— Cu'.tila'jE-cokpv.-cles from
A Frontal Section of the Coxdyle
OF the Femur of a Pup, Five Days
Old.

A, solid vacnoled corpuscle ; B, corpuscle with
one solifl naclens; C, corpuscle with two solirl
nuclei. Ma^ified 800 diameters.

\.

2>

Fig. 1.5.— Cartilage-corpuscles from a .SA<:.iTT.^ Section of the
Condyle of the Femur of a Pup, Slx Week.s Old.

A . corpuscle liolding, besides the nucleus, several larper /granules ; B, corpuscle with a soUd
oblong nucleus at the periphery ; C, con>u8cle with two solid nuclW ; J>, soUd, vacuoled
coTpnscle. Magnified 800 diameters.

shining substance are less frequent than in the cartilage of a newly
born animal, and the substance often exhibits larger vacuoles.

I)h'\'j:iJ)J'Mh'X'J' OF LIVIXa MATTEU.

49

In tlu' tliiii layer of cartilapfe of a (lo^^ ci^lit to ten years
old, the eonipaet shinin<r suhstanee is relatively scarce, and, as
a rule, traversed by vacuoles. Most of the cartilage-cavities con-
tain a ])ale <rranular ])r()to])lasm and vesicular nuclei with dark

contours, and a varying
number of nucleoli. (See
Fig. IG.)

These features were
found in the middle re-
gion, between the articu-
lar surface and the border
of the epiphyseal bone. In
young animals, the yellow
substance, on an average,
occurs the more the nearer
to the bone the examina-
tion is made. Immediately
on the border of the bone
the centers of the large
cartilage-cavities, which
are inclosed by a calcified
basis-substance, are occu-
pied by large masses of the
yellow substance, which
in this situation is supplied with numerous vacuoles, and with
lower powers appears coarsely granular. Each central lump is
suiTOunded l)y a zone of a pale, finely gTanular or structureless
substance, which is separated by a light, narrow rim from the

Fig. 10. — Cartilage-corptiscles from a
Sagittal Section of the Condvle of
THE Femur of a Dog, Eight to Ten
Years Old.

A, corpuscle with sevei'al gra}- lumps besides the
vesicular nucleus ; B. corpuscle with au hour-glass-
shaped nucleus ; C, corpuscle with au oblong central
nucleus. Magnified 800 diameters.

:^\i

Fig. 17. — Boxe-corpuscles from a Longitudinal Section of the
Thigh-bone of a Pup, Five Days Old.

/', corpuscle witli a vacuoled shining nucleus; B, basis-substiince.
diameters.

4

Magnified 800

50 THE PHASES OF

calcareous basis-substance. Sucli formations are absent in old
animals.

Bone-corpuscles. In comparing bone-corpuscdes of a newly
born with those of an old dog, a difference in the structure is
apparent. The cavities of the former contain a central globular,
oblong, or angular vacuoled lump of a yellowish color, and
intensely shining. Around this lump there is a j)ale, finely
gi'anular protoplasm ; the spokes springing from the central
hmip blend with the pale protoplasm, or, in places where the
latter is apparently wanting, with the basis-substance of the
bone. We not infrequently meet with bone-cavities entirely
filled with the yellow, shining substance. (See Fig. 17.)

In the bone of a dog, about ten years old, there are but few
corpuscles, with pale yellow shining nuclei ; whereas cavities
with pale protoplasmic bodies and pale nuclei largely prevail.

m

I m

Fig. 18. — Bone-corpuscles from a Longitudinal Section of the
Thigh-bone of a Dog, Eight to Ten Years Old.

P, corpuscle, with a vesicuLir iiucltMis ; B, 1)a8i8-siil)stance. Magnified 800 diameters.

The latter represent gray, vacuoled lumps or vesicles, with one
to two yellow shining, or one to three gray opaque nuclei,
of which the former usually are larger than the latter. (See
Fig. 18.)

Corpuscles of the 2Ie(lulla of Bone. The medulla of bone also
exhibits marked differences of age. In the medullary spaces of
a shaft-bone of a new-born pup, the apparently homogeneous
basis-substance holds small, yellowish, shining lumps, either
globular or elongated, either homogeneous or vacuoled. Besides,
there are pale protoplasmic bodies with globidar nuclei, similar
in aspect to the lumps just described ; also pale bodies are seen
without nuclei, but in their place cavities with one or two opaque

Dh'Vh'lJU'Mh'XT or LI Visa MATTKIL 51

corpuscU's ; and. lastly, we iiu'ct with pale, finely jifranular proto-
plasmic bodies devoid of nuelei and nucleoli.

As the growth of the animal advances, no medullary spaces
are found in the ])one, but canals for vessels instead. The medul-
lary elements in the space Itetween the wall of the ])lood- vessel
and the border of the l)one are mostly spindle-slia])ed, and either
yello\\'ish, vacuoled lumps, or pale protoplasmic bodies, with and
without distinct nuclei and nucleoli. In all instances the com-
pact lum})s, the ])ale ])rotoplasmic bodies, the nuclei and nucleoli,
are bordered by light rims, which are traversed by radiating
spokes.

In old aninuils. pi-otoplasmic bodies of the above description
ai-e rare ; in the nuirrow spaces of the shaft-bones they are usually
transformed into fat.

My conclusion, drawn from these observations, is that the
proiophismn shows difftreiires (icronliny to its (ujc

The shape of the youngest protoplasm is that of a compact
lump of the li\'ing matter, \A'ith the following properties : It is
homogeneous, has a yellow tint of varpng intensity and shade, a
considerable luster, and admits of being stained red by a solution
of carmine, and violet by a solution of chloride of gold.

In this condition, with our present means of examination, no
reticulum is demonstrable. This condition is similar to that of
a tetanic lump of a contracted amceba, and identical w4th
the condition of the living matter which I termed, in 1872,
*' ha?matol)lastie," in which the li^'ing matter produces both red
blood-corpuscles and the wall of the blood-vessel. For small
lumps of this substance, which are directly converted into red
blood-corpuscles, the term " hfematoblastic '' remains appUcable,
though the hfematoblastic substance has a significance wider in
sense than it seemed to have at the time the name originated.

The first noticeable differentiation in young protoplasm con-
sists in an accumulation of liquid in vacuoles. The vacuoled
condition of haematoblastic sul)stance is the first step in devel-
opment, as observed in the lumps and nuclei of the tissues of
somewhat older animals. The first formation of the walls of a
vessel depends on this differentiation, inasmuch as the vacuole
represents the earliest ca\dty of a vessel.

Owing to an aceiunulation of a liquid in several closed cavi-
ties of the young protoplasm, the Li\dng matter assumes the
shape of a frame- work. The points of intersection of the frame
becoming granules by a rupture of many of the walls of the vac-

52 THE PHASES OF

uoles, a net-work is established, wliieli represents a later phase
of development of protoplasm. The more coarse, yellow, and
shining', and the more densely arranged the points of intersection
of the li\ing reticulum are. the nearer it is to its youth : on the
contrary, the more delicate, devoid of color and luster, the gran-
ules are, the more advanced is the age of the protopla.sm. That
under certain circumstances the liWng matter in the proto-
plasmic lump, by endogenous formatif»n, rejjroduces its own
kind, is proved by observations of older amoebae. Here the
coarse granules are newly formed living matter in a juvenile
condition.

"SVith this explanation we can easily understand the differ-
ences of age in the elements of tissues, described above. The
originally homogeneous lump of protoplasm, with increase of
size, is transformed in its peripheral portion into a net-work,
whereas the central portion, the nucleus, remains homogeneous.
Xext a differentiation into a frame- work, and in turn into a net-
work, takes place in the central lump, the nucleus, so as to leave
smaller, compact centers, the nueleoU. This condition furnished
the scheme of the " cell" of the authors.

At last the differentiation into a net- work has involved the
whole protoplasmic body. At this stage no nucleus, and later
on even no nucleolus, is perceptible, for the whole body is split
up into a reticulum, with coarser and finer points of intersection,
and this condition immediately precedes the formation of a basis-
substance.

The li%'ing matter passes through these stages, not only in the
normal, progi-essive development of all tissues, but, as I will
demonstrate later, also in the process of inflammation, though
here in a reversed manner.

The first assertions as to a difference of the nuclei depend-
ing on age are made by Th. Schwann.* According to this author,
the nuclei in the juvenile condition are solid, later become hol-
lowed, and at length completely disayjpeai-, or are absorbed. S.
Strieker i maintains that the nucleus of the first globule of .seg-
mentation originates in the protoplasm, and that the nucleus in
its youth represents a lump, while with advancing age it may be
transformed into a vesicle.

* Mikroskop. Untersuchungen iiber die Uebereinstimmung in der Stmetar
und dem Wachsthum der Thiere und Pflanzen. 1839. Pages 205 and 211.

t Handbuch der Lehre von den Geweben. Art. *' Allgemeines uber die
Zelle." 1868. Page 24.

DEVKLOl'MEXT OF LIVlMi MATTKK. 53

Lastly, I wonlil take into consideration a j)eculiarity in
tlu' pliases of litV of the protoplasm, as evidenced In' obser-
vations on living corpuscles in a healthy as well as a diseased
condition.

Yonng:, compact protoplasm is in a high degree possessed of
the property of coalescing with analogous protoplasm, and thus
change its configuration, whereas it exhibits the property of
active mobility in a slight degi-ee only. The power of locomo-
tion is entirely al)sent. Under certain circumstances — f. i., on the
border of ossification of the epiphyseal and intemiediate carti-
lage"— the living matter is split into pieces, broken apart. The
best representation of a normal di^'ision I have ol)served in the
hjiematoblastic sultstance within the cavities of the cartilage, the
results of which division are the haematoblasts.

The power of active motion e\adently increases by degrees ;
the more the liquid accumulates in the mesh-spaces of the proto-
plasm, within certain limits of its bulk, the smaller and paler,
therefore, the gi-auules become. The ''pale and finely granular"
protoplasm of the authors, which holds a very delicate reticulum,
has also the most marked capacity of locomotion, upon raising
its temperature to that of the whole body in a normal condition
and in fever. The capacity of compact nuclei and nucleoli of
changing shape and place, on the contrary, seems to be ver^-
limited or wanting. We must consider the protoplasma of the
latter foi-mations as relatively the younger, so far as its shape is
concerned.

Thf^ Celhfheortj in the Light of these Researches. The theory of
the animal cells, as established by Th. Schwann,* was greatly
altered in 1861, by the researches of Max Sehultze.t Since then,
the best obsers^ers have agreed that '' cell" was to designate a lump
of protoplasm, without a membrane and even without a nucleus.
It was added that the protoplasm appeared structui-eless. E.
Briicke'sl attempt to show that the lump was an "elementary
organism " was, for that time, in a certain sense, progress.

The term " ceU '' remained, although a different meaning was
attached to it than at the time of its origin, and aU observers

* Mikroskopische Untersuchiingen iiber die Uebereinstimmung in der
Structur und dem Waclisthxim der Thiere und Planzen. Berlin, 1S39.

t Ueber Muskelkorperchen und das, was man eiue Zelle zu nennen habe.
Mulleins Arehiv. 1861.

t Die Elementarorganismen. Sitzungsber. d. Wiener Akademie der Wis-
sensch. IS 01.

54 THE PHASES OF

seemed to consider it a necessity to include all possible form-
elements within this improved scheme of a cell.

S. Strieker,* in 1868, for instance, discusses the question
how larg^e a lump of protoplasm ought to he to entitle it to the
name of a cell, and comes to the conclusion that we should
speak of a cell only if the lump exhibits growth and repro-
duction. At that time it was already known that, with the
highest powers of the microscope, very minute, just perceptible,
granules grow under our very eyes. The doctrine of the
so-called zymotic diseases almost necessitates the assumption
that the carriers of the contagion are organisms, not subject
to our observation even with the best lenses. Are not the
innumerable corpuscles in decomposing liquids individual organ-
isms in spite of their minute size, which renders them hardly
perceptible even with our best optical apparatus ? And all
these minute organisms should be called cells. Very probably,
a granule of living matter may be altogether too small to be
perceived, and such a granule will agree as little with the idea
of a cell as it will with the idea of an elementary organism.

Wbat at that time was called a structureless, elementary
organism, a "cell," I have demonstrated to consist only in part
of living matter, while even the minutest granules of this matter
are endowed with manifestations of life. The cell of the
authors, therefore, is not an elementary, but a rather compli-
cated organism, of which small detached portions will exhibit
amoeboid motions.

The nucleus cannot be considered an essential part of the
cell, for all good observers know that there are cells destitute of
nuclei, and some authors have distinguished nucleated cells from
" cytodes" — ceU-like bodies devoid of nuclei. (See page 2.)

We can escape from the difficulties of a definition only by
abandoning the designation " cell," in the sense of the zoologists.
By this, our usual terminology wiU remain unaltered. The
amoeba, f. i., or the colorless blood-corpuscle, the • protoplasmic
lump in the colostrum, the pus-corpuscle, are formations to
which the term " cell " is not usually applied. We need no such
word for properly designating what we mean by saying the
amoeba, the colorless blood-corpuscle, etc., are alive ; or the
amoeba, the colorless blood-corpuscle, are organisms.

Such were my conclusions in 1873 (1. c.J^ and here I wish to
add a few remarks more as to the propriety of the term " cell."

*Handbueh der Lehre von den Geweben. Art. " Allgemeines iiber die
Zelle." 1868.

nhrhijij'MK.XT OF Livixa mattkr.

55

Till' size of a living- Ixxly is not included in the definition
of an or<>^anized individual. In the infusion, f. i., we see
g^rowingf g7'aniiles, just percepti])le to the highest inao;nifying
powers of the mieroseope, in a fluid in which none were seen
a short time before.- The smallest individuals which we are
ca])able of seeing with the best mici-oscopes of to-day, are
granules ; but we must admit that germs or particles of living
matter may be present in the air or in fluids in infinite numbers,
which cannot be seen at all, and l)econu' visil)le only after having
attained a certain size. How comj)licated the structure of a
minute particle of living matter may be, we can hardly imagine ;
what we do know is, that the so-called '' cell " is composed of
innumerable })artieles of living matter, every one of which is
endowed with properties formerly attributed to the cell-organism.

The observati(m of the phases of development of the living
matter demonstrates that the term ''cell" was attached to only
a limited number of forms, diu'ing the changes that take jilace
in a growing granule of a substance known to be the seat of
life. As the term " protoplasm " was adapted to the original
idea of the cell, it also meant only one or a few phases in the
development of a lump of living matter. (See Fig. 19.)

Fig. 19. — Diagram of the Phases of Development of the
Living Matter.

L, series of developiiient of a small granule, a, into a vacuoled lum]), h and c, and into a
frame-work, d. P, series of development into jjrotoplasm of a reticular structure ; tlie so-called
•' cell," e, -n-ith a solid, /, </, li, with vacuoled nuclei. B, series of development tending toward
the formation of basis-substance ; in i, the nucleus reticular, the nucleolus solid ; In k and I,
the nucleolus splitting; and in m, the original granule a transformed into a fiuelj- reticular
mass, destitute of nucleus and nucleolus.

56 THE PHASES OF

The series of progressive changes, tending toward the forma-
tion of protoplasm, proves that the original grannie is the
morphologically simplest appearance for our present means of
observation. The growth and splitting of the granule results in
the appearance of a reticular lump, a rather complicated organism,
hitherto termed '' protoplasm "' ; and thus the relation between
the two is about the same as that between an oxuvn and a grown
animal body. That a single lump of protoplasm — f. i., an
amoeba — is endowed wdth all fundamental ^-ital properties attrib-
uted to the whole organism — f. i., a mammal — is acknowledged
to-day by all physiologists. M. Foster attributes to the amoeba,
which he considers an '' undifferentiated protoplasm," the follow-
ing properties: It is contractile; it is ii'ritable and automatic ; it
is receptive and assimilative ; it is metabolic and secretory ; it
is respii'atorj^ ; it is reproductive.

All this holds good for isolated lumps of li\'ing matter, sus-
pended in the liquids of the animal body. Is it applicable to
complex masses of this matter — to tissues ?

As I shall demonstrate later, there is no such thing as an
isolated, individual cell in the tissues, as aU cells prove to
be joined throughout the organism, thus rendering the body
in fofo an indiv-idual. What was formerly thought to be a cell
is, in the present yievr, a node of a reticulum traversing the
tissue. Neither is there a good reason for speaking of proto-
plasm, or for claiming that it is protoplasm which builds up the
animal body; for Hving matter appears in the organism in
various shapes, and it is but one of these, viz., an advanced
stage of development of the living matter, which was hitherto
termed " protoplasm."

According to my observations, we have not to deal with
cells as foi-m-elements, either in the fluids or in the tissues of
the animal body, but only with living matter, varving in its ap-
pearance from the just perceptible gi-anuleto the bulk of the body
of the largest animal. Single limips of living matter may either
look homogeneous or show a net-like arrangement, whereas the
body of an animal is a continuous mass of living matter or net-
work aiTangement, and contains fluids in blood and Ivinph vessels,
in which there are suspended isolated bodies, either homoge-
neous or reticular in structure, as analogous to the gi-anules
which float in the vacuoles of an amoeba. The difference in
the aspect of the tissues depends on the presence of a lifeless
basis-substance onlv, a derivative of the lifeless '• protoplasmic

1U:VKL()PMK}<T OF LI VIS (J MAlTKli. 7)1

fluid," while tlie liviiif^ matter of the tissues exists mainly in the
reticular stajife, and is intereonneetcd without iut('rru])ti()n
throuj^lumt the l)ody.

The question arises, are we justified in speakiujy^ of " cells" as
the formative elements of jilants ? The li\4n^' matter of plants is
not nuiterially different from that of animals, so far as its appear-
ance is concerned. W. Kuehne discovered vegetable lumps of
protoplasm exhibiting amoeboid motion and locomotion, almost
identical with that ( )f ama^bji?. In fresh tissues of plants the liv-
ing nuitter was for a long time known to 1)6 endowed with motion,
as the granules were seen by E. Brlicke and others, floating briskly
in a liquid. My own limited researches enable me to assert that
the gi-anides of living matter in vegetable protoplasm are, as a
rule, united in the shape of a reticulum in the same manner as in
animal protoplasm. Besides, the researches of W. Hassloch (see
page 40) elucidate the identity of both animal and vegetable liv-
ing matter in a satisfactory manner. I may add that all cells of
the vegetable organism are uninterruptedly connected by means
of delicate offshoots, piercing the walls of the cellulose. The
gi'anules of amylum are transformed living vegetable matter.
The plant in tofo is an individual, and not composed of indi-
vidual cells.

The present generation of histologists will very probably
never realize the harm done by the misnomer " cell," so tirmly
established diu-ing the last forty years. Nevertheless, I shall
make an attempt to replace former misnomers by new words
and terms, the originator of which is L. Elsberg.* He says :

The formerly unquestioned" cell" views of histologists are giving way to
a more correct appreciation of tlie li\'ing matter of the body. In pathology,
as in physiology, the cell doctrine has led to great advances in accurate
knowledge as an aid and means of research, but it has outlived its useful-
ness. Instead of adhering to Virc how's comparison, "that every higher organ-
ism is like an organized social community or state, in which the individual
citizens are represented by the cells, each ha\ang a certain morphological
and physiological autonomy, although, on the other hand, interdependent and
subject to the laws of the whole," we now compare the body to a machine
in which, though there are single parts, these are materially connected to-
gether, and no part is at all autonomous, but all combine to make up one
individual. According to the former view, the body is composed of colonies
of amoebae; according to the latter, the body is composed of one complex

*Xotife of the Bioplasson Doctrine. Transactions of the American Medical Association,
1875. Contrihutions to the Normal and Pathological Histologj- of the Cartilages of the
Larj-nx. Arcliives of Laryngologry, 1882.

58 THE PHASES OF

amoeta. I have named this biological doctrine, which is based on Heitzmann's
discoveries, the "bioplasson doctrine," nsing the word "bioplasson" only as a
technical synonym for the two words " living matter" ; and I use the term
" plastid," proposed by Haeckel, or that of " bioplast," proposed by Beale, to
denote a so-called " in'otoi)lasmic body," or a form-element, a formerly so-called
" cell." Perhaps it would ])e the best to restrict the word "bioplast " to a small
mass of living matter exliibitiug no differentiation, and to distinguish from it
as " plastid" the larger mass showing an interior structure more or less like the
fully developed corpuscles. Thiis, I would always use the terra '' plastid" in
the place of "cell."

The word " protoplasma " is etymologically incorrect for designating living
and formative matter, as it has already been used by some authors with a
meaning other than the simple one here intended ; and as it has not yet be-
come so common that its retention or rejection is a matter of much conse-
quence, I propose the designation "bioplasson doctrine."

The word plasma (xi TtXaajJia) really means the formed, that which is
formed, and plasson (to rCka—oy) the fornihif/, that which forms or does
the forming. The distinction is the one so justly insisted upon by Beale in
his discrimination between f/erminal or liri)i{j matter and formed material. The
term plasm may, perhaps, be appropriately applied to the material formed
from the fluid of living matter, the intermediate or intercellular substance of
authors ; but the term plasson only can be applied to active, living, forming
matter. Proto (TCpwxo-) is a prefix signifying first, primary, primordial;
and protoplasma has been used by some to denote the original or first-formed
organic matter. But the term we are in need of for our biological doctrine is
one that shall be an expression for living formative matter in its simple
elementary form ; and for this purpose, it seems to me, bioplasson may appro-
priately be chosen.

The General Constitution of the Body, as Recognized by Single
Plastids. In 1879* I published facts which, perhaps, are of
some vahie to practical medicine, and certainly elucidate the prac-
tical value of the new discoveries. I reprint my assertions with
the only alteration that, in accordance with the new terminology,
as suggested in the foregoing article, instead of ''protoplasm''
and "protoplasmic body,'' I use the terms " bioplasson " and
" plastid."

The amount of living matter within a limited bulk of a plastid
varies greatly in diif erent individuals. It is obvious that what is
called a healthy or vigorous constitution is based upon a large
amount of living matter in the l>ody, the new growth of which
in morbid processes is very lively ; while a strumous or scrofu-
lous or phthisical constitution nnist be caused by a relatively
smaU amount of living matter, the new growth of which is

* " The Aid which Medical Diagnosis Receives from Recent Discoveries in
Microscopy." Ai'chives of Medicine, February, IS 79.

DKVKLOl'MKXT OF LlVlMi MAITEU. oO

scanty in morhid processes. In other words, a plastid will ('xhi))it
coarse <irannlations, oi- it will be almost homof^eneons-lookin^
under the niicroscoj)e, owinji; to the lar«;e amount of livin*i^ matter
in strouf? individmds of good constitution, while a j)histid taken
from a person with weak or strumous constitution will be finely
i:;rannlar, as but little livin<j- matter is ]n-esent in it.

Two years a«»'o, I announced* that pus-corpuscles show
remarkable differences in their minute structure in different
individuals. Those from otherwise healthy and strong persons
jvre yellow, almost honiogt'neous, or coarsely jz;ranular, I said,
while those from broken-down, weakened, or strumous persons
are pale ijray and finely granular. This fact has been made use
of in hundreds of cases, when pus-corpuscles, mainly in urine,
were broug-ht by different x>hysicians to my laboratory for exam-
ination, for telling: whether the pus belongs to a good or a bad
constitution, of course without any knowledge of the patients
themselves. I was right in every instance ; not one mistake has
occmTed.

About one year ago I announced t that the colorless blood-
coi-puscles also demonstrate striking differences as to theii'
minute structure, according to the general constitution. I said
that the colorless l^lood-corpuscles are coarsely granular and
slow in their amoeboid motions under the microscope, if taken
fi'om healthy, vigorous, strong persons ; on the contrary, they
are pale gray, finely granular — viz., poorly provided Avith living
matter — in broken-down or phthisical individuals. I expressed
my hopes that at some future tiiue i^ractical use might be made
of these differences. To-day my hopes have turned, after three
years' earnest study, into accomplished facts.

The method of examination of the blood for our purpose is
extremely simple. We oil the edges of a thin covering-glass on
one side with a cui-led piece of paper, serving as a brush. Prick
with a pointed pin the palmar surface of the thumb, neai' the
wrist-joint, thus giving a good convex surface, and being least
incommoded by the injury. Squeeze out a small drop of blood,
the size of which has to be learned by some practice. Place the
glass slide on the tb'op for transportation, and immediately cover
up the specimen with the covering-glass, the oiled edges looking
toward the slide. Such a specimen holds the blood in a living

* See page 32.

+ "On the Nature of Suppiirative Proeesses of the Skin." A paper read
before the County Medical Society of New York, 1877. Unprinted.

60 THE PHASES OF

condition at least one hour. It is not necessary to use the heated
stage, because the cok)rless blood-corpuscles exhibit their struct-
ui'e in an ordinary comfortable temperature of the room — nay,
sometimes show slight amoeboid motions. The magnifying power
should be at least 800 diameters, the lens to be used being best a
one-tenth of an inch immersion. As a matter of course, the lens
we use must be first-class. Considerable skill is required for
such studies, which embrace first the knowledge of the structure
of the bioplasson in general. A few months' — nay, a few weeks'
— thorough study under the direction of a reliable teacher will
suf&ce to enable every one to see what really can be seen in the
plastids, and to entitle him to judge also of the differences. I
never had difficulties in demonstrating the net- work structure of
the plastids to any one who was in earnest with his microscopical
studies, and took them for more than play. After having ob-
tained a certain practice, one is enabled to tell differences in the
anatomy of the colorless blood-corpuscles with a power of 500
diameters only.

Several years ago, I was first struck by the fact that the ele-
ments establishing the condition of catarrhal pneumonia and of
tuberculosis, both acute and chronic, are decidedly pale and finely
granular. Next I learned that pus and colorless blood-corpuscles
of strong men are partly homogeneous, or at least coarsely
granular. Then I followed these studies by examining the blood
of different physicians who came to work in my lal)oratory, and
who could give reliable histories of both theu* families and their
own bodies. Thus I have arrived at a point of perfection which
allows me to tell the constitution of a person without knowing
anything of his former life.

Besides the differences in the structure of the colorless blood-
corpuscles, as described above, valuable hints may be obtained
from other circumstances. The number of colorless l)lood-cor-
puscles in a given drop of blood is surprisingly different in differ-
ent persons ; the better the constitution, the fewer are these
bodies. A sleepless night, however, is sufficient to increase theu'
number, which fact often enal)led me to tell physicians, by exam-
ination of theii' blood, whether business was going slowly or hvely,
the latter inducing sleepless nights, or repeated awakening by
patients, or so-called nervousness.

Catarrhal processes, so-called colds, of any of the mucous
membranes, lead to increase of the number of the colorless blood-
corpuscles ; a chronic condition of these processes is indicative

DEVEIJU'MKM' (JJ' LI VIS a MMTKIt. Gl

of a poor constitution per se. The colored blood-corpuscles
gfreatly vary in their yellow tinge in different persons; the paler
this tintje is, the more readily we can tell i)ale looks of the face or
chlort)sis. The colored Ijlood-corpiiscles stick together in coin-
like rows only when the plasma holds a larger amount of fibrin ;
in the blood of persons Avith a poor constitution, such rows do
not occiu"; in individtials of moderate vigor, the rows temporarily
may be missing, at other times present. In the blood of persons
of good constitution, who had passed through severe ailments, I
several times found l)oth coarsely aud finely granular colorless
blood-corpuscles, just as in originally healthy persons who, by
chronic diseases, become broken down. In fact, the microscope
reveals so much of the general health of a person that more can
be told by it, in many instances, than by the naked eye, or by
physical examination.

Life insuranee should be based upon microscopical examination, as well
as on percussion and auscultation. Mamages should be allowed, in doubtful
eases, only upon the pei-mit of a reliable microscopist. Last season a young
physician asked me whether I believed in the maiTiage among kindred. He
fell in love with his cousin, and so did the cousin with him. I examined his
blood, and told him that he was a '" nervous" man, passing sleepless nights, and
had a moderately good constitution. The condition being suspected in the
kindred lady, marriage was not advisable for fear that the offspring might
degenerate. So gi-eat was his faith in my assertions that he gave up the idea
of maiTying his cousiu — offering her the last chance, viz., the examination of
her blood. This beautiful girl came to my laboratory, and, very much to my
surprise, I found upon examination of her blood a first -class constitution. The
next day I told the gentleman, " You had better marry her."

As a matter of course, every particle of the organism, either in
a normal or in a morbid condition, will exhibit characteristics as
attri})uted to the colorless blood-corpuscles. The bioplasson is
one uninterrupted mass throughout the body, and is connected
from the top of the head to the heels, in what we call tissues.

Several months ago, Dr. Paul F. Munde brought me a specimen of the
size of a pea, which, he said, he found in a large amoimt of fluid blood
vomited out half an hoiir before by a patient. After immediate examination
of a section fi'om the specimen, I told the doctor that his patient was a pale,
emaciated, narrow-chested person, who had catarrhal pneumonia, which led
by localized gangrene to sloughing of the piece of the lung, on which a broken
blood-vessel was Aisible. I foretold, besides, that the patient woidd die within
one year. I explained to the doctor and to Dr. L. Elsberg, who also was
present in the laboratoiy, what led me to such a diagnosis and prognosis.
There were Aisible alveoli of the lung, and both the walls of the alveoli and
their calibers were crowded with inflammatory corpuscles, coagulated fibrin
being absent. These are symptoms of catarrhal pneiimonia. In some parts

62

THE J'l/ASKS OF

clusters of micrococci could be seen — characteristic of putrefaction, there-
fore gangrene of the tissue. The inflammatory corpuscles looked very pale
and finely granular, the evidence of a bad, phthisical constitution, and all
these signs together allowed the diagnosis of a limited viability, hence the
disastrous prognosis. The doctor told us that no physical symptoms could be
found in the lungs justifying rny diagnosis. Still he admitted right away
that the patient was a j»ale-looking, thin, and narrow-chested young man,
whose Vjrother had been sent to Florida some time ago for chronic tuV^ercu-
losis of the lungs. One week afterward, the doctor came to tell me that the
physical symptoms at present were so marked in the lungs, that the diagnosis
of catarrhal pneumonia was evident. Seven weeks afterward the j>atient
was dead.

The facts here laid before the m
vince even the most skex^ti'-al pliv

'^

Fig. 20. — Diagram of Pus-corpuscles
OP Persons of a Different Consti-
tution.

K, \iUv,Mir\ix\w\ft of an excellent wjnstltntion ; Die
bloi»Ia«»ori nearly wtnipact, containing a few Hruall
vacuolftH, alive In a, alive ami contracted In h, deail
and wjntracted in c. G, iMiH-coi7)U»cle« of a ffotxl
conHtitullon ; the bioplaHMOn eoaim^ly Kranular,
alive in a, alive anrl contracted in h, dead and
contract<;d in c. M, imH-corjinMclr- of a niiddlinK
gfKMl conHtitiition ; the bioplaHHon Ichh coarne, with
a compact niicleuH ; alive in a, anxeboid in b, dead
in c. i\ piiH-cori>ii»cle of a i»oor (lonHtitiition ; the
bioi)la«w>n comparatively Hcaice, finely (ri-annlar,
vesicular nuclei veiy diHtinct ; alive in a, amo!boid
in h, dead and burftted in c.

cdieal j^rofession may con-
sician that microscopy is
destined to play an impor-
tant part in the science of
medicine. Let us proceed
in skillful, honest work, and
we shall succeed in raising
the standard of microscopy
still hig'her, and make it not
only a valuable, Vjut rather
an indispensable, assistance
to clinical work. Mue-h more
could and should be done in
this country by the jjrofes-
sion at large than is done
at i^resent, for the perfection
of that most interesting and
useful science, the science of
ourselves — Biology.

Only little is to >)e added
to these assertions. Several
years' more study has con-
vinced me of their correc^t-
ness, and the difference in
the appearance of biojjlas-
son, according to the differ-
ence in the general consti-
tution, is so striking as to
admit of a diagrammati<;
representation, for which
we may choose pus-corpus-
cles. (See Fig. 20.)

ni':vj:i.<>i'MJ':xT of uvisa mmtkh. 63

Wln'iu'vt'r we inoi't witli |)us-cor|nisclrs in a spofimoii of
iiriiic or sjnita, or, for iiistiiiicc, with colorless Itlood-corpiisclcs
in a dro]) of blood, wliieh exhibit the features liere illustriitcd in
a uniform ninniicr, tlu" conclusion as to the general constitution
of the individual can be made with certainty. Tlu^ exclusive
presence of ])us-corpusclcs of the series P is a sui"e siii'u of a
so-called '' tuberculous or phthisical" constitution.

Should jms or l)lo()d corpuscles of the series E be mixed with
those of the series (i and .1/, this means that an ori<,nnally excel-
lent constitution has become lowered l)y disease — the more so
the greater the numlx'r of the corpuscles like those of the series
P. Persons of a modei-ately ^ood constitution, broken down by
chronic ailments, or by circumstances not favorable to their
nutrition, <i:radually exhil)it, mixed with corpuscles of the series
il/, those of the series I*. The presence of the series I* admits of
longevity rarely, and only under the most favorable external
Ciuiditions ; the more the formations r of the series /' prevail,
the surer it is that the death of the individual is approaching.

Many other conclusions as to the significance of the amount
of bioplasson ])resent nnist l)e postponed, as they are not as yet
suiTticiently proved. Ol)viously, these may in the future lead to
an important medical achievement in the prevention of disease.

The features I have described as to the stages of develop-
ment of living nuitter must l)e combined with the conclusions
just stated, l)ecause the plastids of tissues — I am sure of those
of bone and cartilage — exhibit, in all stages of development,
differences due to differences in general constitution.

V.

THE STRUCTURE OF COLORED BLOOD-
CORPUSCLES.

By Louis Elsberg.*

THE discovery of red corpuscles in the blood was one of the
first resiilts of microscopical study, over two hundred years
ago. Since that time no other constituent of the body has been
more frequently examined. Nevertheless, the structure of col-
ored blood-corpuscles has not heretofore been ascertained.

The examination of a small drop of fresh human blood, mixed
with a drop of from 40 per cent, to 50 per cent, saturated solu-
tion of bichromate of potash, and highly magnified,t reveals in
the course of a few hours the following :

Perhaps the fii'st thing noticed is that the colored corpuscles
vary in size.

* "Annals of the New York Academy of Sciences," vol. i., 1879.

t My investigations were made with a ,V immersion objective, mami-
factured by ToUes, of Boston, and a No. 12 immersion made by Verick, of
Paris, either of which, with the eye-piece that was used, magnities about 1000
times. An exceedingly thin cover having been oiled near the edges, the drop
of blood obtained from a pin-prick in the palm of the hand, and transfeiTed
on a slide, is mixed with a drop of the solution previously prepared, covered,
and vrithout delay placed on the microscope stage. By a 50 per cent, satu-
rated solution, I mean a saturated solution diluted with an equal quantity of
distilled water; by a 40 per cent., one containing three-fifths water; by a
60 per cent., one containing two-fifths water, etc. : I always prepare a sat-
ui'ated solution, and then dilute.

STurcrrui': of coloih-:]) iu.ood-coki'USCles. (m

llaviuji" iiKulc a uuiuIxt of meiisuri'iiicuts, 1 can state that in
I'verv person's hlood that I have examined, there are some as
small as, or smaller than, the j^y-;, and in nearly every j)erson's
some as lary;e as, or larger than, the ^t'cT *'^ ^^^ ineh in diameter
(i. ('., .OCX)");") and .00917 mm.), with transitional sizes between
these. The extremes are sometimes not met with in eacth field of
a drop, nor even in every drop of a person examined ; hut I have
not found any adult of either sex from whose blood the smaller
extreme was al)sent, and only i'ery few without the larger. I
have repeated the measurements of blood-corpuscles without
the addition of the re-agent, both with and without oiling the
edges of the covering-glass, — /. e.^ with and without preventing
the ordinarily rapid evaporation, — with practically the same
results; drying of course contracts blood-corpuscles, and cor-
responding variations are observed. Some of the disks are in
outline not perfectly circular ; by measuring the largest diameter
of the largest and the smallest diameter of the smallest disks,
the extremes I have met with in one and the same specimen of
human- blood are, as to the smallest, about the goVo? '^^^ ^^ to
the largest, the a^-Vo? ^^ ^^ inch fi e., .00422 and .01016 mm.).
If the detached globules, which I shall describe, be counted as
blood-corpuscles, there are even still smaller ones. In each speci-
men of blood, the majority of red corpuscles, however, are of about
one size, which differs in different specimens, but is most fre-
quently between the ifg-Vs and the ^tju) of ^^ i^ich (.006.").") — .00819
mm.), or somewhere about the g^yg of an inch (.0075 mm.). The
calculated average of the size of the red coi'puscles in a drop —
i. e., the arithmetical mean of the measurements — is usually a
little higher than the size of the majority of the corpuscles.

A very few, especially the smallest, but occiu'ring exception-
ally also among the larger, seem more or less globular ; all others
are bi-concave disks, the periphery being more shining and thick
than the central portion.

So-called "rosette" and "thorn-apple" forms may be seen,
either immediately or in the course of a little while. I have often
watched the individual corpuscles while these forms, and many
others, were being produced ; and in Part III. of this communica-
tion I shall offer an explanation of their production.

Concentrating our attention upon the shape of the circular
disks, we soon find that the round outline of a few (and the same
is at times also true of the smooth sm-face) begins to be made

66 STBUCTUBE OF COLOliED BLOOD-COIUTSCLES.

iiTegular at one or more points. This occurs in either of two
ways, viz. : by indentation and by protrusion ; sometimes the
one, sometimes the other, first takes place ; frequently both
appear in different corpuscles at about the same time; occa-
sionally l)oth are met with in the same corpuscles ; in differ-
ent preparations either the one
or the other predcmiinates.

First. In from fifteen min-
utes to an hour a very slight
indentation may appear, and
gradually deepen, so that the
corpuscle be nearly cleaved
through ; then the clefts may
gi'adually become shallower, so
that again a mere indentation
is seen ; finally, even this may
disappear, and the corpuscle be
rounded again (see Fig. 21, aj.
Division into two separating
halves I have never ol)served
under these cii'ciimstances, al-
though I have often watched
for it. The furrow of every
coi-puscle that I have caught
nearly cleaved through, either
remained stationary, or usually
reti'ogressed to a greater or less
extent. The retrogression may
stop at any point, and the fur-
rowing again increase ; and
this going and c(miing of a
cleft, though taking place
slowly, may continue for some time, and then stop at any stage
of indentation. Sometimes indentations appear at two or more
points of the same corpuscle, and in their progress give ri^e to a
great variety of angular, regular, and irregular " rosette," " scal-
loped," '' crenated," " thorn-apple," and '" stellate" forms (see Fig.
21, &, c, dj. The sharp-pointed ends seen in the last figure of d
are the extremes met \Wth,- and exceptional ; usually the ends are
plump and rounded. These forms, as well as those of single
cleft, after changing backward and forward, either persist or
become finally rounded off to a greater or less degree ; in some

-Q

Fig. 21.-
Blood

TION.

- Shape-chaxges of Colored
•corpuscles by ixdexta-

a, progressing and retrogi-essing furro-vriiifr ;
h, indentations leading to irregular foi-ms:
c, indentations leading to more or less regular
forms; d, instances of extreme and excep-
tional forms, esiiecially the .sharp-pointed stel-
lated figure ; e, four phases of form-change,
observed in one corpuscle, vrith separation of a
constricted portion.

STUrCTCliE OF COIJJJU'^JJ JllJJOJJ-COJa'l'SCJJ'JS.

(u

cases constriction of ])ortions more or loss inirmtc occurs, with
scj)aration t(»llo\vin^^ cousti-iction (sec Fi<x. 21, cj. Sometimes con-
stricted portions remain attached for a lon^ time 1)y a moi-e or
less loufX and slender i)edicle. Trausitioiially or permanently, in
any of the cases mentioned, the most curious and jL^otesque shapes
maybe nu't with. In tlie cases, too, of constriction and separa-
tion, the corpuscles, with the porti(ms attached and unattaclied,
sometimes ^adually bec^ome rounded off so as to look like a
])arent ijlobule surrounded by a number of little ones.

Sirondlii. Usually in tlie course of half an hour, the protrusion
of little round or roundish, more or less light colored, knobs takes
place. At first, only very few corpuscles show knobs, and the
knobs are extremely small and few in number, say only one, or
at most two or three, on a corpuscle ; but in the course of an
hour or two, more cor-
puscles protrude knobs,
more knobs are pro-
truded from one corpus-
cle, and the knobs grow
larger (Fig. 22, (i). Occa-
sionally a knob is drawn
in again, and the former
contour reestablished. In
some instances protru-
sion and retraction occur

repeatedly, so that knobs a, Nos. l ami 2, progressive and retrogressive protru-

' -J 1 . ^ siou ; No. 3, one pedunculated and three sessile knobs ;

appear and disappear, or j^^ 4, detachment of two knoljs; &, protrusion of knobs

become larovr and small- ** t''*5 perlpliery and on tlie surface; in No. 3, the knobs

'^ surround the whole body of the cori'uscle ; and In No. 4,

er, very slowly init repeat- tluy are still more numerous.

edly, for some time. Oc-
casionally a knol) is pedunculated, and sometimes becomes de-
tached from the corpuscle, while, on the other hand, some knobs
are qmte sessile.

I have measured portions detached in either of the two w'a^'s
described, and found them to vary fi-om the 3oooi> ^^ the - Jgo of
an inch (.00084 — .00338 mm.). All except the very largest may
usually be seen in constant oscillatoiy (molecular) movement,
and, unless entangled between larger stationary corpuscles, easily
moving across the field (the latter probably caused by minute vari-
ation from absolute equilibrium level of the microscope stage).

In some dentated or so-caUed "miilberry" forms, knobs or
small eminences protrude from the face of the disk, which may

Fio. 22.

-KXOB-FORMATIOX, PHIXCIPALLV

BY Protrusion.

68 STRUCTUBE OF COLOliEl) BLOOD-CORFUSCLES.

give to the inexperienced observer the impression of internal
gi*auules; )3ut proper focusing corrects this impression, and
shows the knobbed surface. (Fig. 22, h).

Fig. 23. — Coalescence of Two or More Corpuscles, Givixg Rise to
Chains and Irregularly Shaped Compound Bodies, with the Net-
work Structure Visible.

In addition to the protean changes in shape initiated by in-
dentation and protrusion, there are still others occasionally met
with, due to combination or coalescence of two or more cor-
puscles. In the coui-se of twenty-four
hours or more — though this occurs
in by far the smaller number of prep-
arations of blood examined — two or
more adjacent colored blood-cor-
puscles may, with a larger or smaller
portion of tlieii' periphery, unite
and form compound bodies, some-
times chains or other strange shapes.
(Fig. 23.)

Almost immediately on being ready
for examination, a very few colored
blood-corpuscles show a light central
vacuole. In the course of the examina-
tion, a number of vacuoles, either of
different sizes or all of the same size,
may appear in a corpuscle. Usually,
a vacuole is round or roimdish, but it

Fig.

24. — Vacuoled Cor-
puscles.

In the upper liue are seen three
corpuscles, each ■witli a different
sized central vacuole ; in the middle
line, the first ligure shows three vacu-
oles in one corpuscle; these vacuoles
are represented in the second figure

tobeclosetogether, and in the third ^n^Y aSSUUlC VariOUS UTCgular fomiS
figure, the separating walls of ap- -^ » i • i ^ i, l,

parently five vacuoles luive broken SOmC ot WhlCh may JjernapS UaVC

down, and one irregulai-lv shaped j-gg^^g^J fp^j^ a uuiou of SeVSral, and
larger vacuole is seen. The lower " _ » i -•

line shows the appearance of vacu- the breaking down of the Separating

oled corpuscles seen on edge. ^^^^^ ^^^_^ j,.^.^ 24. The three loWCr

figures show appearance of vacuoled corpuscles seen on edge.)
Vacuoles sometimes persist, and sometimes, after a longer or

sThTcrriiH or coi.oiiFjt lu.ooD-coin'rscLKs. m

shorter coiitinuaiKH', suddenly dis;i])i»('ar. Tlit^y are either empty
or else eoutaiii one oi- iiioi*e ^rautdes.

Soon after the eoi'pnscles are studied, sometimes from the
first, a difference is noticeable as to the intensity of their colora-
tion ; some are paler tlian others. Gradually a larger number of
corpuscles become pale, and the degree of paleness, too, increases.
There is a great difference in respect to the rapidity of "paling"
of colored corpuscles, in blood taken from different persons, even
in blood of the same person taken at different times, and with
different strengths of the admixed solution of bichromate of
potash.

Usually, in l)lo()d of healthy persons, examined as I have
described, in about an hour from the time the drop of blood is
placed on the slide, a few of the corpuscles that are least deeply
colored appear to have become somewhat granular in their inte-
rior. Focusing shows that this is notthe optical illusion alluded
to in the case of knobbiness of the siu'face.

Soon the granules or dots seem more distinct ; short, conical
thorns, or more delicate spines, appear to issue from one or two
of the largest of them ; and, on close inspection and focusing,
some appear to be connected by ii-regularly concentric filaments.
In the course of five minutes more, a complete net-work is dis-
tinctly seen in the interior of one or more corpuscles, and what at
first appeared to he granules turn out to be thickened points of
intersection of the threads forming this reticulum. These points
or dots are irregularly shaped, and vary in size. (See Fig. 2").)

Fig. 2."). — The Structure of Five Colored Blood-corpuscles.

In the liist, tliere is seen an ciiciiclinir hand of unifovm tliickncss, in wliicli are inserted
nnnierons tliroails of a network; a nninlxT of knots are in tlie interior, wliicli are seen to
1)0 the points of intersection of tlireails eonstitntinfr a net-work: in tlie lower portion of the
ilisk there is a larjrer knot, which may be called a unelens. In the fifth coriiiiscle the com-
plete net-work strneture is best seen ; in this cori'nscle there is seen at the periphery, instead
of an encircling hand, a number of knots united by threads, having the appearance described
a.s beads, each a little separated from its neighlxn-s on the string. Tlie second corjiuscle
shows the net-work and encircling band, as the nia.lorit.v of corpuscles show them. In the
third, a lighter baud is seen, and an irregular tlaj), produced by either indentation or protru-
sion, or both. The fourth exhibits a large flap or knob at its lower portion, with a stretched or
extended net-work.

Radiary threads of the net- work terminate at the periphery
of the corpuscle, either with thickened ends connected by threads

70 STRUCTURE OF COLORED BLOOD-CORPUSCLES.

— giving an appearance of unevenness to the outer boundary, as
though it were constituted by a wreath of beads, each bead sepa-
rated from its neigh})()rs on the string — or, far more frequently,
with terminal points lost in an encircling band of a uniform
thickness, often greater than either the interior threads or most
points of intersection. From this appearance, as well as that of
the so-called '' ghosts," to be pr(!sently described, it is not to be
wondered at that careful observers have ascribed to colored blood-
corpuscles the possession of an investing membrane.

As the "paling" progresses, an increasing Jiumber of cor-
puscles show the interior net-work, essentially as I have just
described, and identical in construction with
the net-work discovered by C. Heitzmann
in amoebae, colorless blood-corpuscles, and
other living matter of the body, a discovery
which I communicated to the American
Medical Association more than three years
ago.

Gradually an interior net-work structure
])ecomes visible in nearly all the corpuscles
in the field, except the smaUest, which appear
more or less compact ; and occasionally a
corj)uscle is met with having a central, or
slightly eccentric, dot of such relatively large
size that it might be interpreted as a nucleus.
Some movement takes place in the net- work;
for sometimes the threads change in length,
and perhaps in thickness, and the dots change
their position and their size.

In the course of another half -hour or hour,
the net-work becomes less distinct in the
palest corpuscles; and in these gradually
fades away. Then, for some time, the net-
work remains visible in nearly all corpuscles
except those that are too pale or too small;
vacuoles, one or more, appear in many of
the latter ; while the former occasionally
show indications of irregularly massed matter in their interior,
though usually nothing is seen of them but double-contoured
rings which have been called their ''ghosts" (see Fig. 26).
During this time, also, a quantity, sometimes rather large, of
detritus accumulates.

Fig. 26.— The Final
Phases op Colored
Blood - corpuscles
Treated with an
Appropriate So-
lution OF Bichro-
mate OP Potash.

In the ui)per left-hand
ligure there is a doubl(^
coutouicd ling, with ir-
regularly massed matter,
showing traces of a net-
work; in the lower right-
hand ligure this is less
distinct; and in the two
lower lef t-liand figures are
represented two so-called
"ghosts'"; above these
there is detritus —i. e.,two
or three detached por-
tions; and to tlie riglit-
hand upper ligure there is
attached a muss which has
appaiently been extruded.

STitucTvni': of colokkd iilooh-coui'Usci.ks. 71

It a|)))('!ii-s as though the net-work is in<»st plain in corjmscles
that liavi' sutft-rcd either not at all or bnt little from detaeh-
meut of a portion of their substance. The active changes of
indentation and pi'otrusion have usuallv disa])peared in a large
nnniber of corpnscles, l)v the time " paling- " has snfificieutly
progressed to render the interior structure visible. As before
stated, some corpuscles permanently retain scalloped and
knobbed forms, while the majority are finally more or less
rounded olf; bnt the i)lay of changing shape of many corpuscles
is going on at the same time that this net- work is seen.

After a while, further '' paling " stops, and the net- work
structure of all corpuscles which show it, remains visible
indefinitely long.

Blood-coi-puscles, from hemorrhage in the bladder, in the
urine of the late Di-. H****y, preserved with some bi(;hromate of
potash, still show the net-work after three years.

Specimens of blood taken from different individuals exhibited
all the phenomena described, but with some slight differences
among each other as to the order and time of appearance.

A 40 per cent, saturated solution of bichromate of potash,
admixed with the blood, was found entirely satisfactory for the
demonstration of all the phenomena; and some variation of
strength — /. ^., between the limits of a 35 per cent, and a 50 per
cent, saturated solution — made no appreciable difference.

Of other solutions of bichromate of potash, it is sufficient to
state the following :

With a 30 per cent, satui-ated solution, the phenomena are
also to be seen, but appear more slowly, and quite a number of
corpuscles usually remain more or less unpaled.

With a 20 per cent, satnrated solution, the changes proceed
still more slowly; comparatively few indentations occui*; the
net- work of the majority of corpuscles is visible after the lapse
of twenty-foiu- hours, l^ut many remain entirely unaffected.

With a 10 per cent, saturated solution, vacuolation appears,
also a little changing indentation and protrusion, but not suf-
ficient paling to render the net-work visible even after several
days.

With a GO per cent, saturated solution, the majority of the
corpuscles had already become pale by the time the specimen
was in place for examination. Some showed interior net-work,
some only double-contoured rings. Protrusions were seen,

72 STRUCTURE OF COLORED BLOOD-CORPUSCLES.

especially iu the corpuscles not iniicli paled ; in one instance,
a pale ring "was also seen with a large pedunculated protrusion
(Fig. 26). During two hours, changes of scalloping and of knobs
took place faster than is usual with blood mixed with a 40 per
cent, or 50 per cent, saturated solution, but they could not be fol-
lowed so distinctly. Extreme paling rapidly proceeded, and much
detritus filled the field, with only very few compact globules.

"With a 90 per cent, saturated solution, the process of scallop-
ing was completed in twenty minutes ; and in thirty minutes a
net-work was visible in a few roundish corpuscles, sun'ounded
by masses of granular detritus. In addition, a large number of
" ghosts " could be seen. Here and there a " ghost " would show
a faint net- work.

"With a saturated solution added undiluted, the net- work was
after one hour visible iu some corpuscles, but most of them were
destroyed ; of a few left intact, some looked homogeneous, and
some vacuoled. The field was full of faint, double-contoured
rings and a large quantity of granular detritus.

The net- work structure of colored blood-corpuscles is \'isible
also in anatomical preparations which have been kept for a length
of time in Miiller's fluid.

In some of my examinations, especially the earlier, I used the
heated stage ; but as the phenomena described were seen at the
ordinary temperature of a well-warmed room, I deem it best not
to say an}i;hing here of variations of temperatui*e.

In this communication I omit the mention, also, of the
remarkably varying amount of fibrine threads seen in different
preparations of blood ; nor do I enter at length into the question
of '' detritus formation,'' or whatever else one may interpret as
the appearance in the field of an increasing number of free gran-
ules, and granular masses or plaques.*

In addition to himiau colored blood-corpuscles, I have exam-
ined those of lower animals. Essentially the same intimate
structm-e as that which I have described exists in all. As exam-
ples, I will quote from my note-book a few words referring to
the examination of the colored blood-corpuscles of the ox and
the newt — the one an example of the unnucleated, the other of
the nucleated corpuscles.

* Max Seliiiltze, who saw some of these gi-anules and gi-anular plaques in
healthy blood, prefers the designation ''granule foi-mation," as being non-
committal.— Archiv fiir MiJcroslcoinsclie Anatomic, vol. 1, p. 38.

STllUCTUUE OF (U)lAUiKD BLOOD-CORVLSCLES. 73

A drop of fresh ox-])loo(l, iiiixod witli a ;")() per cent. Haturated solution of
hicliroiiuite of i)()t!isli, and liijjldy niaj^nified (Tolles's \\, immersion) exhibited,
within twenty nnnutes, vacuohition l)e;jinninfx in several red corpuscles.
Within forty minutes, knobs were protruded, thouf^h not <'Oi)iously. In the
course of an hour, " paling " proceeded regularly, so that the net-work Ijecarae
\isible in some, and within two hours in a large number, of the coi-puscles.
After three hours the net-work, the note-book says, was very distinct in
many corpuscles, with some detritus and a few "ghosts." Twelve hours
later, about one-half of the whole luimber of corpuscles showed the reticulum,
while the other half were either vaciuiled or unchanged. No further change
was observable for two days. After the third day, some few corpuscles, per-
haps, that had not sho^ni the net-work structure before, now did; but the
paled ones had become too pale to do so, except a very few which showed it
finally. The rest had become " ghosts," with much detritus. A week later,
nearly all the corpuscles that had exhibited the net-work had become
"ghosts," only in a very feAV of which faint traces of the reticulum could
be made out. The rest were still unchanged, as on the first day, and remained
so as long as the specimen was kept.

The red blood-corpuscles of the newt, exaniiued iu a 50 per
cent, saturated solution of bichromate of potash, into which, a
drop of the blood from the freshly cut tail had been allowed to
fall, presented peculiar changes of shaj^e, consisting- mainly in
contractions of the body around the nucleus.

The nuclei always exhibited the net-work structure, either
perfect, and more distinct than in specimens unmixed with the
solution, or, when the nucleus was swelled to double or treble its
original size, with the net-work torn. Just as in the case of the
coh:)rless corpuscles, there were seen two kinds of red corpuscles,
finely granulated and coarse granular, the granules always l)eing
the points of intersection of the threads of the net-work. In
both kinds, the body as well as the nucleus exhibited the reticu-
lum structure. The net- work of the body and that of the nucleus
were connected by fine threads passing thi'ough the nuclear
envelope. In many instances the body was reduced, either to two
polar flaps, bulging from each side of the nucleus, or to one flap,
more or less colored, at the side of the nucleus ; in other instances,
it was uniformly contracted around the enlarged nucleus.

Many colored corpuscles contained vacuoles, in varying niun-
ber, which were either empty or traversed by an exceedingly
delicate, apparently stretched, reticulum, or else contained u'reg-
ular accumulations of matter with remnants of the net- work.

II.
My observations as to amoeboid movements of colored blood-
corpuscles, as well as to varieties of size and shape, — observations

74 STEUCTUME OF COLORED BLOOD-COBPUSCLES.

which were really only incidental while investigating the struct-
irre, the main object of my researches — have been anticipated
by previous investigators. One saw, and reported as an extraor-
dinary finding, one or more forms or active form-changes like
those I have described ; another others ; some a far greater num-
ber than I. " Fehlt Jeider nur das (jeisiuje Band.'' The band
which connects and explains the phenomena observed is the
discovery of the structural arrangement.

In the following historical sketch of points bearing on my
observations, I shall refer to a few only of the legion who
have made colored Ijlood-corpuscles the subject of their investi-
gation.

More than a hundred yeai's ago, William Hewson, after asserting that the
red eorpiiscles are of different sizes in different animals, added : "I have like-
wise observed that they are not all of the same size in the same animal, some
being a little larger than others,"* etc. Hewson's editor, Gulliver, who has made
a very large number of measurements of red blood-eorpuseles of different
animals, and is " our highest authority upon the subject," said of his own
elaborate tables : "We are only speaking now of the average size, for they vary
like other organisms ; so that in a single drop of the same blood you may find
corpuscles either a third larger or a thii-d smaller than the raean size, and
even still gi'eater extremes " ; t and more recently,]: ' ' But as I have long since
shown, the corpuscles in one species of the vertebrate class, as seen in a
single individual thereof, vary so much in size that their average dimensions
cannot be determined with absolute precision ; and were this fact kept in
view much needless discussion might be spared."

Beale, also, long ago called attention to the fact that "corpuscles may be
found which are not more than the fifth or sixth of the size of an ordinary
blood-corpuscle. "§ Again : "The red corpuscles vary in size, and more than is
usually supposed " ; || and again : "It is generally stated that the red blood-
corpuscles of an animal exhibit a certain definite size ; but it will be foimd
that they vary extremely, so that corpuscles exist of various dimensions." If

Welcker ** found in the blood of Dr. Schweigger-Seidel colored blood-cor-
puscles as small as. 0051, and as large as .0085 mm. Altogether, the mini-

■ •' Pliilosoijhical Transactions," vol. Ixiii., Part n., \i. 320 (read June 24, 1773). The works
of William Hewson, F. 11. S., Edited, with an Introduction and Notes, by George Gulliver,
F. K. S., London. Pul>Iisheil by the Sydenham Society, 184C ; j). 23-1.

t " Lectures on the Blood of Vertebiata." Medical Times and Gazette, vol. ii. of 1862,
p. 157.

t "Comparative Photographs of Blood-disks." Motitltly Microscopical Journal, Novem-
ber, 1876, p. 240.

§ "Archives of Medicine," vol. ii. (No. 8), p. 236, and Quarterly Journal of Microscopical
Science, April-May, 1861 ; p. 249.

II " Observations upon the Nature of the Red Blood-corpuscles." Transactions of the
Microscopical Society of Loudon (read Dec. 9, 1863), vol. xii., N. S., p. 37. Quarterly
Journal of Microscopical Science, 3a.ii., 1864.

» " The Microscope in its Ai)plication to the Practice of Medicine," third edition. Re-
published in Philadelphia, 1867 ; p. 170.

** •' Grosse, Volnm und OberHache und Farbe der Blutkorperchen bei Menschen und bei
Thieren." Zeitsclirift fiir rationelle Medicin, S. ill., vol. xx. (1863), p. 237.

STliVCTriiK OF COLoni:!) HLOOD-COIU'ISCLP^S. 17)

mum measurcmiMit recorded in his table \h .004;") mm., and the maxitiium,
thoufrh not in tlie same specimen, .()0<,»7 mm. He remarks : " I have always,
both in animals and in man, fonnd tlie transverse diameter of the blood-
corpuscles of one and the same individual vary from one-fourth to one-half of
the mean nu>asurement ; and it api)ears that all the sizes lyinjj ])etween the two
extremes are i)resent in toleral)ly ecjual numbers, with the exception of the
smallest corpuscles, which occur ft)r the most ])art sinj^ly and at intervals."*

Max Schultze distin-fuished in liis own and other persons' healthy blood two
forms of colored corpuscles, viz. : globidar aiul disk-like ; the globular, few in
number, vary from .005 to .00() mm. in size ; and from these there are ^&A-
ual transitions to the ordinary disks, which measure from .OOSto .(»!(» mm. t

The snuiUest colored corpuscles wliich Klebs reported t having toimd in his
own blood varied from .OOTiS to .OOOti mm. ; but in blood fi'ora the corpse of
a leucivmic child he observed a few as small as .00-411) mm.

Woodward said : " The trutli is that not only do the individual corpuscles
in every drop of blood vary considerably in size, but as might be anticipated
from this very fact, the average size obtained by measuring a limited number
of corpuscles (;")() to 17.5, still more in the case of but 10 to 50, as usually
practiced), varies considerably, not only betsveen different individuals, but
also between different parts of the very same drop of blood." Both the maxi-
mum and the minimum which he found — \'iz. : the 39 G millionths and the
210 millionths of an inch, or .01005 and .00548 mm. — were present in the
same field of one droj).!}!

Berchon and Perrier|| state that the colored blood-corpuscles of the
foetus and the newly born are on an average smaller than those of
adults. The extremes given are: minimum, .0031 to .0002 mm., and
maximum, .0091 to .0093 mm. ; but they do not mention that the extremes
occun'ed in one and the same case. More recently, PeiTier If measured
blood-corpuscles of thu-ty-five intUviduals of different ages, and found that
those of .010 mm. were very frequent in the first days after birth, w-hile later
they occiirred much more rarely. After the first year, blood-corpuscles meas-
uring .0093 mm. were rarely present in gi-eater proportion than ten in a hun-
di-ed ; and in adults often absent. Such of .0043 mm. occurred most often in
the aged and in childi-en. The diameter of the gi-eat mass at every age varies
from .0050 to .0087 mm. ; within these limits those of .0075 mm. are most
frequent and never absent. The form of the smaller is more or less globular ;
the larger are flattened.

* Cited bj' Woodward, " On tlie Similarity between the Red Blood-conniscles of Man and
thoae of certain other Animals, especially the Dog : considered in connection with the diajnio-
sis of Blood-stains in criminal cases." American Journal of Medical 6'Cit'nces, Jan., 1875.
Monthly Microscopical Journal, Feb. 1, 1875, p. G9.

t " Eiu heitzbarer Objecttisch iind seine Verwendung bei Untersuchungen des Blutes."
Archiv fiir Mikroskopisclie Anatomic, vol. i. (1805), p. 35.

i " L'eber die Kerne iind Scheinkerue der rotlien Blutkorperchen der Saugethiere.'"
Virchctw's Archiv fiir pathologische Anatomic und Physiologie und fiir Klinische Medicin :
vol. xxxviii. (18()7), p. 105.

i " The Application of Photographj' to Micrometry, with special reference to the micro-
metry of blood in criminal cases." Transactions of the American MeiUcal' Association, vol.
xxvii. (1876), p. 303-315.

II " Note sur les globules du sang chez le foetus." Bordeaux Medical., p. 123 and 237 ;
Canstadt's Jahresbericht for 1875, I., p. 46.

^ " Sur les variations liu diam^tre des globules rouges du sang dansl'espece humaine, au
point de vue de resperti.-*e legale." Conipt. Rendus, tom. 84 (1877), No. '24, p. 1404.

70 STRUCTURE OF COLORED BLOOD-CORPUSCLES.

Accordiiif^ to Hayejn,* the red l)lood-corpuscles in the newly born are
much less uniform ill size than in adults; corpuscles larger than the largest
and smaller than the smallest adult corpuscles occur comparatively often.
The size varies between .00325 and .010135 mm. Hayem also calls atten-
tion t to the still smaller ones — measuring only .002 mm. — which he considers
young and growing blood-corpuscles, so-called h^matoblasts. He asserted
having observed all transition sizes between these apd the largest. He found
hsematoblasts increased whenever, under physiological or pathological condi-
tions, a reparation of blood occurs — e. g., he found them more abundant in
children than in adults, and more abundant during menstruation, and after
losses of blood, also during reconvalescence after acute diseases. t

Netsvetzki reported § having found minute corpuscles moving in all direc-
tions, as constant constituents of normal human blood. [Although my obser-
vations as to the diversity of size of colored blood-corpuscles refer to healthy
blood, I will not omit to mention here that Vanlair and Masius having, in the
blood of a patient who had symptoms of interstitial hepatitis, found a number
of small globular corpuscles, gave them the name of microcytes, and called the
patient's disease ''microcythsemia," which they considered to be a peculiar
alteration of the blood. || Cases of so-called microcythemia have since been
reported by Litten, in a tuberculous individual ; IT by Osier in pernicious
anaemia ** ; and by Lepine and Germont in cases of cancer of the stomach. tt
Soernsen distinguished in disease between oligocythemia, in which the num-
ber of red blood-corpuscles is diminished, achroiocythemia, in which their
richness in coloring matter is diminished, and microcythemia, in which their
size is diminished. In a case of chlorosis observed by him, the average size
of the colored corpuscles was found to be only .0045, instead of the normal
.006 to .0075 mm.tt

Hicks § § found in the fluid from an ovarian cyst small, transparent, color-
less, globular bodies, which had been detached from red blood-corpuscles, and
which were of a diameter of about the tttJutt of an inch.

Laptsehinsky reported |||| finding very small corpuscles, only one-third as

■ " IH-H caractfeit'S anatomiqiies «Ui sani? chex lo nouveau-iie poiidaiit les in-emicrs jours de
la vie." Conipt. Rendiis, toiii. 84 (1877), )). IIGO.

t " Snr la nature et la .siyiiitication des petils Klobules rouges ilii saug." Ihid,, No. 22,
p. 1239.

: " Note SUV I'ln'olutiou (U-s gloljulcs rouges dans le saug dcs vcrtdires ovipares." Conipt.
Reiidus, toni. 8.5, No. 20, p. 907-909. " Siir revolution des globules rouges dans le sang des
aniiuaiix superieurs" (verteb. ovipares). Ihid., No. 27, p. 128r>.

(> " Zur Histologie des Mensclienblules. Kleine sieh iiarh alien Itielitungen Iiiii bewc-
gende Korperclieii als eonstanto Bestandtlieile des normaleii MenM(lieiil)lutes." Ceiitral/.eit-
uiig t'iir die Medicinisclien Wissenscliafteii, 1873, No. 10.

II " ])e la Mieroeytliemie, Bruxelles, 1871 ; 101 pji.

i; •' Aus del- Kliiiik lies Jlerni Geli. Itath. Prof. Frerichs, " Ueber eiiiige Veriinderuugeu
rotlier Blutkorpercben." 15erliner Klinisclie Wocliensclirit't ; 1877, No. 1.

*-■ " I'elier die Kntwickelung von 151utkdrperelieii in Kiioclienniark bei pernicio.ser Aiiifi-
niie." Centralblatt t'iir die medicinisclien Wissenseliaftcn ; 1877, No. 28 ; 1878, No. 26.

it Note sur la pri^seiiee teinixuaire dans le sang liiiniain d"un grand nonibie de globules
rouges tres petits (microcytes)." (iazclte Medicale de Paris : 1877, No. IS, pp. 218 and 219 ;
and " Note relative a riiitliieuee des saignees sur I'apparition dans le sang liumain des iietits
globules rouges (microcytes)." Id., No. 24, iJ. 206.

tt " Undersogelser oni Antallet af rode og lioide Blodlegenier under forskjellige pliysio-
logiske og patliologisko Tilstande." Inaugural Dissertatiim, Koi)eiiliageu ; 1876,236 pp.

'A " Obs<ivatioiis on PatlKilogical Clianges in the Red Corpuscle." Quarterly Journal
of NicroHCoiiical SeU'iicc, \-ol. xii. (1872), jt. 114.

III! "Zur I'atholDgie des Jiliites." Ceiitrall)latt f. d. med. Wiss., 1874, No. 42, p. (i58.

STRVCTriil-: OF iOLOliKl) liLOOD-COlil'i'SCLKS. 77

larfj»' us tlu< iioriniil onos, in conditions of tin- Ixxiy accompanicfl with \\\v\\
fevor, t'spi'ciiilly in infections tJiscascs.

Haycni has come to the conclnsion* lliat in anieniia tlie l)loo(i-cori)nscles
are in general siiniUer tiian in normal conditions; Imt that tlu' extremes
which are met witli are {greater, viz. : .OO'J'J and .(» 1 () to .(» 1 4 mm.

Piper found in u case of "ulcerated scrotum and inflamed testicle, with
apparently tuhercidous deposit in the gland," on one and the same slide,
specimens which measured 4,,'s • of an inch ; while on other parts of the same
sli<lo alike extensive fields of cori»nscles which measured only a fraction less
than the classic ^V|,n of an inch.t

Pontick,} Osier, ikS and Ohermeier || have reported other abnormities.]

According to Kichardson,!! the variations above and below the standard
size of corpuscles from any particular animal are comparatively slight in fresh
blood, as proved by the following experiments, ma<le with his ,'t inch
objective, which gives with the micrometer eye-piece an amplification of
3700 diameters. When thus magnified, the human red blood-disks appeared
about an inch and one-eighth in diameter, so that even slight differences in
their size could be accurately measured. Among one hundi'ed red coi-puscles
freshly drawn from five different persons, the maximum and minimum diam-
eters in i)arts of an inch were as follows :

Twentv from a white male aged 30, maximum 1-32.31, minimum T-3r)00

'' " " " " " 38 " 1-3281 '■ l-3r)20

" " " female " 44^ " 1-3241>', " 1-3500

" " an African " " ,50, " 1-3182, " 1-3559

" " a white male " 8, " 1-3231, " 1-3500

Moreover, the smallest red disks of man, as usually met with in mechani-
cally unaltered blood, whether dry or moist, are, according to him, larger than
the largest corpuscles of an ox, and a fortiori of a sheep.

More recently,** he measured corpuscles of individuals of foiu-teen different
nations, one himdi'ed of each. Of the 1400 corpuscles measm-ed, the average
was 3^4 (.007878 mm.), the maximum ttTt, and the minimum 40^)^ of an
inch ; 1158, or 83 per cent., measured between -^}f-f and ^0'^^ of an inch in
diameter, and consequently under a power of two hundred would appear
about the same magnitude ; the total number of corpuscles of minimum
measure was only sLx, or less than one-half of one per cent. ; and the total
number which measured the maximum w:as ten, or less than one per cent.

• " Des Caracttres Auat<iuii<iues ilu Sang ilans les Anemics." CDinptos Reudus, tome 83
(1876), pp. 8'.'. 85, p. 152, p. 230.

t ••('oiitiaction of Blood-corpuscles tliroiijrh the action of Cold." Ne%o York Medical
Journal, Manli, 1877, p. '2m.

t " Ueber das Vorkonmien abnormer Zellcn ini 151ute von Recurrenskranken." Central-
blatt f. d. med. Wiss., 1874, No. 25.

§ ''An Account of Certain Orffani8iu.s occurrinj; in the Liquor San.iruiuis." Monthly
Microscopical Journal, fSepteinber, 1874, p. 141.

II " Vorkoniiuen feinster, eine Kigenbeweftung zeijjender Fiiden in\ Blut von Recur-
renskranken." Centralblatt liir die nied. Wiss., 1873, No. 10. Coufirnied by Laptscliinsky.
/(/., 1875, No. 9. p. 84.

U "On the Value of High Powers in tlie Diagnosis of Bloo<l-stains." American Journal of
the Medical ficicnccg, July, 1874; and London Monthly Microscopical Journal, September,
1874, p. 135.

'-■ "On the Identity of the Red Rlood-eorpnscles in Different Races of Mankind."
American Journal of the Medical .Sciences, January, 1877, p. 112.

7ft STJU'CTT'liE OF rOLOTiET) TiLOOJj.rOJiPrSf'LES.

All thi« is ven.- remarkable, unless he measured mainly the majority,
or average-sized corpuscles. He made some selection, for he tells us :
*' Instead of measuring all corpuscles, deformed or otherwise, in two direc-
tions, as proposed by Dr. Woodward ( I'hUa. Mcdmd TimcM, vol. vi., p. 457),
I prefer to determine the size of unaltered, i. e. circular, corjjuscles otily " ;
further, "I cautiously avoided reeorfling those which manifested even slight
departnres toward an oval form," but, on the other hand, " to secure the most
infallible accuracy for my deductions, as the jjrejjaration was moved along, I
measured erery isolated circular red disk which came into the field of the
microscope."

In the year 17G1, Padre Jo. Maria de Torre, of Naples, made a present to
the Royal Society of London of four sjiherical glasses for the microscope,
made by himself, of which the diameters and magnifying powers were said to
be as follows :

Diameter. ilAOXirriXG Power.

] . Near 2 Paris points. 640 times, and upward, in diameter.

2. iParispoint. 1,280 " '' "

.3. 1 " " 1,280 " ♦' "

4. Half a Paris point. 2,.560 " " "
(t47 of an inch.)

Sir Francis Haskins Eyles Stiles, at the time in Naples, through whom the
presentation was made, wrote several letters, in which he communicated
Father de Torre's direction for the use of the glasses, as well as an account of
some obser^-ations on the human blood, made by him, together with Torre,
during .July and Augu.st, 1761, and read before the Society during
November, 176.5. They saw in the blood-globules the central depression,
which had not theretofore been ol»served, and which carried with it so
strongly the apx^earance of a perforation that they concluded the corpuscles
to be rings. They also thought the rings to be articulated ("the transverse
lines at the joints being very distinguishable")-" -Aj» to their shape, "the
figure of the rings, where they were free and in their natural state, was
circular; but where they were so crowded together as to compress one
another in their passage, they assTimed a variety of different figures,
although they generally restored themselves to a circular figure again,
unless broken by the compression, which frequently happened, and then
the broken parts floated separately ; or, if they opened at a single joint only,
the whole of the ring would float along, varying its figure occasionally from
that of a portion of a circle, which it would firs-t assume, to a straight line, an
undulated one, or some other accidental incurvature." t

Hewsont declared the so-called globules in the blood of man and all ani-
mals to be disks — "in reality, flat bodies," "as flat as a guinea." The dark
spot in the middle, which Father de Torre had taken for a hole, he found
"was not a perforation, and therefore that they were not annular." He denied
that they were jointed, and inferred " they are not fluid, as they are commonly

* "An Acconntof some Microscopic Observations on the Human Bloo<L" Philosophical
Transactions, vol. Iv. (1765), p. 254.

t Ibid., p. 256.

t " On the Figure and Con)jK)8ition of the Red Particles of the Blof)d. commonly called the
Re«l Olobnles." Philosophical TransactionM, vol. Ixiii., Part n. (177:^), pp. 303-323.

sTiiVCTVUK or (()Ij)j;j:j) nuxnt-coui'iscLKs. 7!)

believod to be; Imt, on the ooiitriuy, are solid; heeaiiKe every fluid swiminiiifj
in another, which is in hirger (juantity, if it lie not soluble in that fluid,
becomes jjlobiilar." He also observed chaufjes of Hlia])e ; for, speakinj^ of the
l)lood-cori)iiscles of a lobster, he said: "But there is a curious chanj^e pro-
duced in their shape by being exposed to the air; for, soon after they are
received on the j^lass, they are corrufjated, or from a flat shape are changed
into irregular spheres, as is represented in Plate XII., No. 12";* and on
turning to the jilate we find represented "angular," "rosette," and "stel-
lated " forms. He was the first wlio likened the appearance of coi'j)uscles,
with tlieir external surface corrugated, to tliat of small mulberries, t

It would be impossible for me, as well as useless, to give a list of all those
who have described changes of form in red blood-corpuscles since Hewson's
time. Different shapes — and some of them far more curious and irregular
than those I have described — have been observed, imdev many physiological
and pathological conditions, as well as on subjecting the l)lood to the action
of various chemical and physical agencies. Text-books and monogi-aphs
give sufficient information on this point, especially the article on the blood by
Alexander Kollet, in Strieker's " Handbuch der Lehre von den Geweben des
Menschen uud der Thiere," which has been translated by Henry Power and
published by the London New Sydenham Society, and which has been repub-
lished in this country. X

Since that article was written the following observations have been made :

Langhans,!^! in experiments on rabbits, saw, in extravasated blood, red
corpuscles with numerous tine projections, and in pigeons' red blood-cor-
puscles, also, observed morphological changes.

Lieberkiihn || described remarkable form-changes in the red corpuscles of
the blood of salamanders and of pikes.

WedlH observed changes of shape in human and frogs' red blood-corpuscles
on adding a drop of concentrated aqueous solution of pyrogallic acid to a drop
of fresh blood.

Ray Lankester*'* found in his own healthy blood, in addition to the ordi-
nary biconcave forms, "thorn-apple" and "single and double watch-glass"
forms. In the two latter there is, Avhen the corpuscle is seen on edge, instead
of a concavity, a convexity on either one or both sides. He also described
and figured varieties of shape in both human and frogs' colored blood-
corpuscles subjected to the action of various re-agents. Of these I shall cite,
later on, the effects of very dilute ammonia gas and acetic acid vapor.

Braxton Hicks ft observed colored blood-corpuscles of various shapes in
fluid from an ovarian cyst, and in blood in other pathological conditions.

* Ihid., p. 321. Opus postliumum, pp. 19, 20 ; Collected Works, edited l>y GuUiver, cit.,
p. 234.

t Jbia., p. 313, etc.

t " A Mami.il of Ilistolofry." By Prof. S. Strieker. American translation edited by Albert
H. Buck. New York: Win. Wood A- Co.. 1872.

J " Beobaclitungeii iiber Resorption der Kxtrava.sate uud Pigmentbilduujj: in denselben."
Virehow's Arcliiv, vol. xlix. (1870), pp. 6G-116.

II " TJeber BewegunK.sersclieinungen der Zellen." Schriften der Gesellscliaft zur Beforde-
nuig der gesanimten Naturwissenseliaften zu Marburg, vol. ix. (1870), p. 335.

TI " Histologisclie ]Mittlieiluiigeu ; Ueber die Kiuwirkung der PsTogallussiiure anf die
rothen Blutkorperchen." Sitzungsbericlite der Wiener Akadeniie der Wi.«i.senschaften, vol.
Ixlv. (1871), 1 Div.. p. 40.5.

**" Observations and Experiments on tlie Bed Blood-corpuscle, chiefly with regard to
the Action of Gases and Vapours." Quarterly Journal of Microscopical Science, October,
1871, p. 3fil-387.

tt Observations cit. Qttartcrly Journal of Microscopical Science, vol. xii. (1872), p. 114.

<S0 STKUCTUliE OF COLORED BLOOD-COUP U SOLES.

Huels * described frogs' red blood-corpuscles acted on by carbolic acid.

Fabert observed, in the urine of a patient with Bright's disease, colored
blood-corpuscles of a great variety of different shapes, some of which showed
him phenomena of contractility and amoeboid movement, "very similar" to
those of colorless blood-corpuscles.

Hiiter j reported seeing in the capillaries of the frog lung a few red blood-
corpuscles adliere to the sides by means of a drawn-out pedicle, with half the
body on each side, having a saddle-bag-like shape (" s we rf/>i(trlc<Hni licit ").

Laptschinsky described and figured § the effects of various re-agents,
among them aniline Idue, magenta, and tannin, on the red blood-corpuscles
of triton and man. He confirmed and enlarged the older observations of
Eoberts.ll Laptschinsky H also described some variations of shape which he
met with on examining human blood in different diseases.

Arnold, ** in the course of his observations on diapedesis of colored blood-
corpuscles after ligating the median vein of the frog's tongue, saw that in the
various phases of transit these corpuscles assumed various shapes, sometimes
pear-shaped, with slender stem, sometimes caudated, oval, etc. Similar
shapes have under similar circumstances been described by others.

Hiller tt refuted the supposition of Huter (II. DeutseherChirurgen Congress,
April IS, 1873), that the stellate and thorn-apple forms of red blood-corpus-
cles are due to immigration of monads into the substance of the corpuscles.
He found such forms in blood during febrile and non-febrile diseases ; they
were absent in some cases in which large quantities of monads had been in-
jected into the blood of animals ; and he observed in many cases their develop-
ment directly under the mici'oscope.

Rommelaere tt observed in various diseases changes of shape of the red
blood-eqrpuscles.

Landois^^ saw corpuscles assume, before theii" dissolution, a spherical
form with exceedingly fine points.

Ebert,|l|| Bottcher,U1f Fuchs,*** and Schmidt ttt have reported variations of
the ordinary shape. The latter has also called attention to the fact that human
red blood-corpuscles, seen in exact profile and closely examined, are repre-

*■• " Wiikiuif? iler Carbolsiinre aiif rotlie Frosclibhitkoiperclien." Inaiig. IJissertatioii,
Grcifswalrte, 1872, 43 pp.

t " Ueber die rotheu Blutkorperclieu." Arcliiv der Heilkunrte, 1873, xiv., p. 481-511.

t " Ueber den Kieislauf mid die Kieislaiifstiiniuseii in der Frcscliluuge." Centralblatt
fiir die Medicinischeu Wis.seimcliaften, 1873, No. (J, p. 82.

^ " Ueber das Verhalteu der rothcn JJIiitkiirperelien v.n einigen Tiuctionsmitteln und zur
Gerbsiire." SitzuiigsberieUte der Wiener Akadeniie, vol. Ixviii. (1873), ])iv. ni., p. 148.

II " On peculiar appearauce.s exhibited by blood-cuipu.scle.s under tlie influence of .solution
of magenta and tannin." Quarterly Journal of Microscopical Science, 18(53, p. 170.

11 "Zur Patliologie des Blutea." Centralblatt fiir die Medicinischeu Wissenschafteu, 1874,
No. 42, pp. 660 and 661.

i> " Ueber Diapedesi.s." Virchow's Archiv, vol. Iviii. (1873), pp. 203-2.'>4.

tt " Ueber die Veriinderungen der rothen Blutkorperchen nebst Beinerknngen iiber
Microcyten." Centralblatt f. d. Med. Wiss., 1874, Nos. 21, 25.

XX " Do la deformation de^s Globules rouges du .Sang." Bruxelles, 1874. 47 pp.

?? " Aufiii-sung iler rothen Blutzellen." Centralblatt f. d. Med. Wiss., 1874, No. 27, p. 419.

nil " Ueber Formveriinderungen der rothen Blutkorperchen." Greif.swald, 1875.

inf " Ueber einige Veriinderungen weh^he die lothen Blutkorperchen in Extravasaten
erleiden." Virchow's Archiv, vol. 69 (1876), p. 295-307. Also in other articles which I quote
in this review.

*** "Beitragzur Kenntniss des Froschblutes und der Froschlymphe.' VircUow's Archiv,
vol. 71 (1877), pp. 78-107.

ttt " The Structure of the Colored Blood-corpuscles of Amphiuma tridactylum, the
Frog, and Man." Journal of the Microscopic Society of London, May and July, 1878, i)p. 66,
68, 110, etc.

STRVCTVHI-: OF ('OlJUiEIi llUXtD-COIirUSCLKS. SI

seiitod by two straiKlit and parallel lines, eonnec-ted at their extremities by
two seinioireular ones, and not showing merely tlioir central concavity, as
usually represented.

The ([uestion whether or not colored Itlood-eorpuscles possess an investing
niembrane has l)een nnich discussed. Hewson, who, as I have already stated,
showed that these corpuscles are not perforated, contended that the dark spot
in the middle, believed by Torre to be a perforation, "is a solid particle con-
tained in a Hat vesicle, whoso middle oidy it fills, and wliose edges are hollow,
and either empty or filled with a subtile fluid." * He detailed the following
experiments : " Take a drop of the blood of an animal that has large particles,
as a frog, a fish, or, what is still better, of a toad ; put this blood on a thin
piece of glass, as used in the former experiment, and add to it some water —
fii'st one drop, then a second, and a third, and so on, gradually increasing the
quantity; and in proportion as water is added, the figure of the particle
will be changed from a flat to a spherical shape; ... it will roll
dowm the glass stage smoothly, without those phases which it had when
turning over when it was flat ; and, as it now rolls in its spherical shape, the
solid middle particle can be distinctly seen to fall from side to side in the
hollow vesicle, like a pea in a bladder." He added: "From the gi-eater
thickness of the vesicles in tlie human subject, and from theii* beuig less
transparent when made spherical by the addition of water, and likewise from
their being so much smaller than those of fish or frogs, it is more difficult to
get a sight of the middle particles rolling from side to side in the vesicle,
which has become round ; but with a strong light (these experiments were all
made with daylight, in clear weather) and a deep magnifier, I have tlistinctly
seen it in the human subject, as well as in the frog, toad, or skate." Another
experiment he describes thus: "If a saturated solution of any of the common
neutral salts be mixed with fresh blood, and the globules (as they have been
called, but which for the future I shall call flat vesicles) be then examined in
a microscope, the salt will theu be foimd to have contracted or shriveled the
vesicles, so that they appear quite solid, the vesicular substance being closely
applied all around the central piece." Fui'thermore, "the fixed vegetable
alkali and the volatile alkali were tried in a pretty strong solution, and found
to corrugate the vesicles."

The vesicular natm-e of colored blood-corpuscles, thus announced more
than sixty years before the publications of Schleiden and Schwann, so per-
fectly fits into their cell-schema that many suppose that they have originated
this \aew of the constitution of the corpuscles. But in point of fact they have
in this respect followed Hewson. According to Schwann,t the red blood-
corpuscle is a cell, and consists, like every other cell of the body, of a
membraneous envelope, a nucleus, and liquid contents; the credit of the
observation of the "rolling around" of the nucleus is given by Schwann to C.

* " On the Figure and Composition ol tlio l{eil Tarticles of the Blood, commonly called
tlio Ked Globules." Pliilosoi)liical Transactions, vol. 63, Part 11., p. 310 et seq. (read Juue
17 aud 20, 1773). "A Description of the Red Particles of the Blood in the Humau
Subject and in other Animals, beinj; the remaining part of the Observations aud Experi-
ments of the late Wm. Hewson." By Magnus Falconer. London, 1777. p. 221 et seq.

t " Jlikroskopische rnteisuchungeu iiber die Uebereinstimmung in 8ti'uctur uud Waclis-
thum der thierischen und ptlanzliehen Organismen." Berlin, 1S39. pp. 74. 75.

6

82 STBUCTURE OF COLOBED BLOOD-CORPUSCLES.

H. Sehultz, who, however, has only repeated and confirmed * the experiment*
of Hewson.

Although not accepted without some opposition, it was not until the year
1861 that the existence of a cell-wall was positively denied. Beale declared :t
" I have never succeeded in seeing the cell-wall said to exist, neither have I
been able to confirm the oft-repeated assertions with regard to the passage of
liquid into the interior of the corpuscle by endosmose, its bursting, and the
escape of its contents through the ruptured cell-wall. When placed in some
liquids, many of the corpuscles swell up and disappear ; but I have never seen
tie ruptured cell-walls." He also published observations which he considered
" fatal to the hjT)othesis that each corpuscle is composed of a closed membrane
with fluid contents." i Briicke expressed the opinion that the rolling around
of the nucleus is illusory, that other phenomena do not conclusively prove the
presence of a membrane, and that " the unanimity with which the vesicular
nature of blood-corpuscles had for a long time been taught was owing more
to the silence of the opponents than to the force of the arguments of the
believers." $ Vintschgau || and Rollett 1" also argued against the existence of
an investing membrane ; and the opinion seemed doomed.

But before the end of the year in which Beale and Briicke contested the
existence of an investing membrane, Hensen defended it. ** He reports
having obsei'ved in the blood of frogs, both in fresh preparations — /. e., in red
corpuscles examined without the addition of any re-agent — and in corpuscles
placed in varioiis mixtures, especially a solution of sugar, that sometimes the
membrane, as a distinct outer contom*. is lifted up from the interior contents
at one or more points of the circumference, these interior contents being
retracted more or less densely upon the nudeiLS. A few years later, tt Hensen
reiterated his conviction as to the presence of a membrane ; it is certain,
therefore, that Lankesterit has misapprehended hLs meaning. Kolliker, who
had previously asserted that the red blood-corpuscle possesses "a very
delicate but nevertheless tolerably firm and at the same time elastic colorless
cell-membrane, composed of a protein substance closely allied to fibrin," $$
continued to uphold their vesicular constitution. |||| Preyer reported that the

* " Das S3-st<>in der Circulation." Stuttgart and Tubingen, 1836, p. 19, et seq.

t " Let-tares on the Structure and Growth of the Tissues of the Human Borly. Delivered at
the Royal College of Physicians. Lecture III., April 22, 1861.' Archive.? of Medicine, vol. ii.,
No. 8 (May, 1861), p. 236. Kepublished in Quarterly Journal of ilicroncopical Science,
vol. i., N. S. (Apnl-May, 1861), p. 240.

t " Observations iipim the Nature of the Red Blootl-corj'uscle." Transactions of the Micro-
scopical Society, vol. xii., >'. S., p. 37. QuarUrly Journal of Microscopical Science, Jan., 1864.

^ "Die Elenientarorganismen." Sitzungsberichte der Wiener Akademle, vol. xliv., Div.ll.,
p. 389 (read Oct. 17, 1861).

II " Sopra i Corpusculi Sangnigni della Rana." Atti del Instituto Veneto, vol. viii., Ser. in.

f " Versuehe und Eeobachtungen am Blnte." Sitziujgsberichte der Wiener Akademie,
vol. xlvi. (1862), p. 65.

** 'Tntersuchnngen zur Physiologic der Elutkorperchen sowie fiber die Zellennattir
derselben.'" Zeit-schrift fur wis.senschaftliche Zoologie, vol. xi.. Heft 3 (Ansgegeben Dec.
23, 1861), pp. 25»-278.

ttin a foot-note of an article entitled " Ueber das Ange elniger Cephalopoden." Jbid.,
vol. XV.. Heft 2 (April 1, 1865), p. 170.

ttLankester, in liis article on the red bloofl-corpnscle, in the Qvarterly Journal of
Microscopical Science. October. 1871, already cited, says, p. 366, that Hensen " distinguishes
a layer of fluid ]irotoplasm surroumling the coloring matter, by cadaveiic alteration of which
he believes the supposed membrane of the <:ori>nscle to be formed."

^"Manual of Human Histology." Trau.slate<l and edited by George Bu.sk and Thomas
Huxley, London, Sydenham Society. 1854, vol. ii., p. 326.

nil Handbuch der Gewebelehre. 1863, p. 627.

sTnrcrriy'h' or ciujmKh HLooit-coiwrscLKs. H3

oarly ol)S(M'vati()n of the rolliiif^ nucleus (erroneously ascrihed \ty him, after
Sehwauu, (o Sehultz instead of to Hewson) afjreetl with what he himself had
seen, and, at least so far as red eorpuscdes of the blood of salamanders are
eoneerned, positively declared a membi-ane normally to exist.* As proof of
the existence of a memlirane, and of its taking no part in the formation of
lilood-crystals, Bryanowski refers to his success in demonstrating it by means
of distilled water, t Owsjannikow says : " To prove with certainty the exist-
ence of the membrane is no easy task. Preparations occur which seem to be
convincing that there is no membrane ; but other preparations show it with-
out the addition of any re-agent. The interior contents retract away from it,
so that between it and the yellowish colored contents an empty space remains.
Still more distinctly than in pure blood is the membrane seen on the addition
of a weak solution of sugar, either without or with admixture of a little
alcohol. Then it appears in many, or perhaps in most, of the blood-corpuscles."
Furthermore, he describes interior crystallization in which he has seen the
membrane pushed out lengthwise by a crystal, and other cases in which
" the membrane becomes very distinctly visible as it passes from nucleus to
crystal." With high magnifying power, he says, human red blood-eoi-puseles
not seldom show a very delicate membrane ; and one of his conclusions is :
" In the blood-coi-puscles of most animals an independent membrane can be
proved to exist, which behaves toward serum, water, etc., tlifferentlyfrom the
cell-contents, and which occasionally possesses considerable firmness. " +
Richardson argued iS in favor of the same view, mainly on account of experi-
ments upon the gigantic blood-disks of the menobranchus, in which "crystals
of hsemato-crystallin were seen. to prop out a visible membraneous capsule."
More recently, Richardson exhibited before the members of the Section on
Biology of the International Medical Congress of Philadelphia, a slide with a
colored blood-corpuscle of the amphiuma tridactylum, of which it is reported
that "the imperfectly crystallized cell-contents occupy the iipper end, while
the oval gi-anular nucleus fills the inferior extremity, leaving the membraneous
capsule relaxed and wrinkled longitudinally, hanging like part of a half-flaccid
balloon between them." || Arloing, as the result of his observations, U ascribed
a membrane to red blood-eoi-puscles. Kollmann, after expressly declaring
that when he uses the word membrane in relation to red blood-corpuscles, he
means to speak of what may be called an "artefact," /. c, "that apparent
membrane which is made visible by the action of reagents," ** discusses the
arguments \>vo and eon, and concludes that "the adherents of a membrane
have for theu- opinions at least as many reasons as the opponents." ft He
himself believes in "the existence of a membrane in the fresh condition,

* " Ueber aiu(tl)<)iile Hlutkiirperclit^u." Vircliow'a Arcliiv, vol. xxx. (1864), p. 437.

t " Beobaclitiiniien iiUer die Bliitkrystalle." Zeitsclmft fiir wissenschaftliclie Zoologie,
vol. xii., Heft 3 (Noveinber 17, 18G2), p. 317.

fZnr Histologie der UliitkiirpiTclicii." Bulk-tiu de TAcadeuiie des Sciences de St.
Peteisbotirjr, t. viii. (1865), pp. 5(j4, 508-.570.

? " On the Cellular Structure of the Ked Blood-corpuscle." Transactions of the Americau
Medical Association for 1870, pp. 259-271.

II Transactions of tlie International Medical Congress of Philadeli>hia, held in 1876.
Philad.li.hia, 1877. p. 488.

H " RechiTclies snr la nature du Globule Sanguin." Compt. Kendus, t. Ixxiv. (1872),
No. 19, pp. 1256-1259.

>'* " Banderrotlien Blutkorpercheii." Zeitschrift fiir wis.senscliaftUclie Zoologie, vol. xxiii..
Heft 3 (November 18, 1873), p. 467.

tt Ibid., p. 482.

84 STRUVTVBE OF COLORED BLOOD-CORPUSCLES.

Avhich can be made visible by the action of re-agents by depriving the cor-
puscle of coloring matter, and which, when it does not become visible, has
been destroyed by the re-agent. " * According to Bottcher, the outer layer of
the same blood-corpuscle is not the same at all times and imder all circum-
stances. He seems to regard the appearance of a distinct membrane as an
artificial production; but considers "the cortical layer as the result of a
process of development which deprives the blood-cells more and more of
their protoplasm, and finally converts them into homogeneous bodies." He,
therefore, classes it "with the capsule of cartilage cells, and with the cellu-
lose membrane of vegetable cells." t Fuchs observed a membrane of a
certain power of i-esistanee in fi'ogs' red blood-corpuscles after keeping them
a few days on the slide without addition of any re-agent, which membrane was
particularly obvious when the nucleus made its exit out of the corpuscular
mass, t According to A. Bechamp, § and J. Bechamp and Baltus, |1 the red
blood-corpuscles of mammals, birds, and amphibia possess a distinct mem-
brane, which can be thickened by adding a solution of starch to the blood,
and then becomes more resistant to the action of water.

It has even been siipposed that blood-corpuscles had more than a single
membrane; thus Roberts saidH his observations had led him "to the belief
that the envelope of the vertebrate blood-disk is a duj)licate membrane; in
other words, that within the oiiter covering there exists an interior vesicle
which incloses the colored contents, and in the ovipara, the nucleus."
Bottcher has refuted this notion, ** and it is characterized by Wedl, too, as
incorrect ; according to Wedl, when the cortical layer becomes swelled and
condensed, the double contour which is seen indicates its thickness — but he
is " quite certain that whether it be called membrane or not, it is not simply
an artificial product." ft Lankester, in his conclusions regarding the verte-
brate red blood-corpuscle, says: "Its surface is differentiated somewhat
fi'om the underlying material, and forms a pellicle or membrane of gi'eat
tenuity, not distinguishable with the highest powers (whilst the corpuscle is
normal and liA-ing), and having no pronounced inner limitation." tt Ranvier
thinks that the double eontom" — the effect of dilute alcohol — "proves the
existence, if not of a membrane, at least of a differentiated cortical layer. " 9$

Schmidt |||| calls attention to the double contour as being "the only proof

* lbUl.,v- 480.

t Conipare " Xfuc Untersuchungen iiber die rotlien Blutkorperclien." Memoires <le
rAcadeuiie. IiiiiHiiitln des Scu'iict't= tie St, Peteisboui^s vii. Serie, t. xxii. (1876), Xo. 11,
p. 8; aud tlie " Untersucliiiuiren " in Virchow's Arcliiv, vol. xxxvi. (1866), pp. 357, 383,
387-9, and 404, -vs-ith Arcliiv fiir Mikroskoiiische Anatomie, vol. xiv. (1877), p. 93, or
" On the Minute Structural Rel}ition.s of tlie Red Blood-corpiiscles " (translated from the
preceding in), Quarterly Journal of Microsco}>ieal. Science. October, 1877, p. 392.

i " Beitras zur Kenntniss de.s Froschblutes," etc., I. c, p. 91.

I " Recherche.'* snr la Constitution Physique du Globule Sangniu."' C'oinpt. Reudus,
t. Ixxxv. (1878), No. 16, pp. 712 715.

II " Sur la structure dii Globule Sangniu, et la r^si.stauce de son envelloppe k raction de
I'eau." Ibid., No. 17, p. 761.

Hi. c.

** Op. cit. Virchow's Archiv, vol. xxxvi. (1866), pp. 392-395.

ft L. c, p. 408.

tt L. c, p. 386.

??"De I'Eniploi d'Alcool Dilu6 en Histologic" Archiv de Physique, 1874, pp. 790-793.
And again, " Recherches sur les Elements du Sang." Id., 2 Serie, vol. ii. (1875), pp. 1-15.

nil "The Structure of the Colored Blood-corpuscles of Amphiunia tridactylum, the Frog,
and Man." .Journal of tlie Royal Microscopical Societ.v; containing its Transactions and

STliUCTlliK OF I'DLOKKl) llLOOD-COUri: SCLES. 85

of tlie presoneo of a inembnino, whetlier prei'xisterit or artificially produced."
In t'rt'sh blootl of ainphiinna he has observed colored blood-coi'puscles with a
j;reoiiish border, indicating "the existence of a thin layer at the surface, dif-
ferinj;, if not in ch(>niical coniposition at least in density, from the substance
of the disks." He lias freqiU'utly met with "specimens of Idood-corpuscles,
on which, by a contraction of the protoplasm I'ejjresentiiig the gi'eater ])oi"tion
of the whole body, the jiellicle in (piestion appears separated fi'ora the latter."
Once he saw a fragment of a corpuscle on which "the membraneous layer was
seen projecting on the torn surface "; and at another time he found "a fresh
blood-corpusch» of the anipliiuma on which the membraneous layer had appai'-
ently l)urst and retracted, leaving a portion of the underlying malerial, the
protoplasm, exposed." He says: " The changes taking place in these blood-
corpuscles, wlien treated with the solution of the hydrate of chloral, are very
interesting and important ; as they manifestly show the existence of the mem-
braneous hiyer of these bodies, such as I have described it. Thus, after the
solution has been applied, the protoi)lasm of the blood-corpuscle, without
much or any alteration of form, gracbially contracts upon the nucleus. As the
result of this contraction, it becomes entirely separated from the membraneous
layer, which manifests itself in the form of a delicate double contour. The inter-
space left between the contracted protoplasm and the double contour repre-
senting the membraneous layer is very considerable, as will be seen from the
di-awings, and, it seems to me, should be sufficient evidence to prove the
existence of such a layer to an unbiased mind." In the colored blood-
corpuscles of the frog, he has also seen a distinct stratum, or membraneous
layer.

" The colored blood-corpuscles of man show a double contour under vari-
ous circumstances and conditions, indicating the existence, if not of an
enveloping membrane, at least of a membraneous layer on its surface." As
one proof, Schmidt recommends the experiment of pressing down, by means
of the point of a forceps, a small round covei'ing-glass upon a very small drop
of fresh himian blood placed upon the slide, " with the object of compressing
or crushing the Itlood-corpuscles as far as possible." " Carefully examined
with a first-class objective of sufficient amplification, it will be foiuid that they
have not run into each other ; but that, on the contrary, the outlines of
almost every individual may be discerned, however distorted they may be."

Almost all investigators nowadays agree that the colored blood-corpuscles of
birds, reptiles, amphibia and fishes liave a nucleus ; while in those of man and
other mammalia, except in developmental forms, a nucleus does not occur.
On this difference, Gulliver has founded his division of all vertebrate animals
into pyi-ensemata and ai^jTensemata.* Biit the existence of a nucleus in
living corpuscles of oviparous vertebrata has been denied on the one hand ;
while, on the other, the opinion has been advanced that the mammalian red
coi-puscles, as well as those of other vertebrata, are in reality nucleated,

Proceertiugs, -with otlier Microscopical liitcllijicucc. Lomlon, vol. i., No. 2 (Ma}-, 1878), pp.
57-78; No. 3 (July, 1878), pp. 67-120.

* "Lectures on the Klood ot Vertebrata," f. c. ; in Journal of Anatomi/ and Physiology,
vol. ii. ; Proceeiiiiigs of the Zoological Society of February 25, 18(52 ; and Hniiteri;ui oratiou.
1863, referred to in "Observations on the sizes and shapes of the red corpuscles of the blood
of vertebrates, with drawings of tlieni to a uniform scale, and extended and revised tables of
measurement." Proceedings of the Zoological Society of London, for the j'ear 1875, Part UI.,
1.. 47'.l.

86 STRUCTURE OF COLORED BLOOJJ-CORPUSCLES.

Not to cite older authors, I will mention that Funke* asserts that the
nucleus of nucleated blood-corpuscles does not exist during life, but is a prod-
uct of decomposition after death. Likewise Savory, in a paper t read before
the London Eoyal Society, urged that "when living, no distinction of parts
can be recognized ; and the existence of a nucleus in the red corpuscles of
ovipara is due to changes after death, or removal fi'om the vessels"; and
furthermore, "the shadowy substance seen in many of the smaller oviparous
cells, after they have been mounted for some time, is very like that seen under
similar circumstances in some of the corpuscles of mammalia." But Bottcher
has reported t seeing nucleated blood-corpuscles in the capillaries of living
fi'ogs, and more recently Hammond saw a nucleus in the red blood-eoi-puscles
of young trout, varying as to age from a day to three weeks, swimming in a
cell full of water ; $ and afterward also in those of the tail of frog-embryos
and in other animals. ||

Bottcher has by numerous methods and for a long time sought to demon-
strate the existence of a nucleus in mammalian red blood-coi-puscles. In his
fii'st publication^ he gave a historical sketch of the literature of the subject,
and described the effects of chloroform, magenta, tannin, and other re-agents.
He also treated corpuscles with serum of other blood; next** he placed them
in aqueous humor ("methods which alter the red blood-corpuscles as little
and as slowly as possible ") ; afterward tt he treated them with alcohol and
acetic acid, and still more recently t+ by means of a concentrated alcoholic
solution of corrosive sublimate (methods of "hardening the blood-corpuscles
and then extracting the haematin fi'om them ''). Freer, using reflected instead
of transmitted light ( by means of Wales' Illuminator), affirmed ^ ^S independently
of Bottcher the existence of a nucleus in human blood; and Piper |||| seems
very desirous to confirm Freer. Brandt, having, Hlf in the red blood-corpuscles
of living sipunculus, occasionally found a nucleus, though usually there is
none, thought that perhaps the nuclei are unstable formations which by slight
influences are produced or made visible, and by others are destroyed or made
invisible ; on examining a drop of blood from his finger, on which he had
before pricking placed a little fresh chicken albumen, he usually found in

* " Lehrbuch iter Pliysiologie." Leipzig, 1863, vol. i., p. 17.

t " On the Structure of till' Red Blooil-corpvisole of Oviparous Vertebrata." Pioceediiig.s
of the Koyal Society, vol. xvu., 1868, 1869 (read March 18, 1869). Monthly Microsco2)ical
Journal, April, 1869, p. 235.

t " Untersuchuugeu iiher die rothen Blutkorperchen der Wirbelthiere." Virchow's Archiv,
vol. xxxvi. (1866), (i)p. 342-423), p. 351.

§ " Ob.servations on the Structure of the Red Blood-corijuscles of a Young Trout."
Monthly Microscoiiical Journal, June, 1876, pp. 282, 283.

I) "Observations on the Stiuctiire of the Red Blood-corpuscles of Living PyrcnuMuatous
Vertebrates." Id., September, 1876, p. 147.

H The "Untersuchungen" just cited, pp. 359, 363, 367, etc., and 376.

** " Nachtragliche Mittlieilung iiber die Eutfarbung rother Blutkorperchen und iiber den
Nachweis von Kernen in denselben." Virchow's Archiv, vol. xxxix. (1868), pp. 427-435.

tt " Neue Untersuchungen iiber die rothen Blutkorperchen." Meuioires de I'Acad. Imp.
des Sci. de St. Petersbourg, vii. .Ser., t. xxii., J\'o. 11.

tt " Ueber die feineren Structurverhiiltnisse der rothen Blutkorperchen." Archiv fiir
Mikrosk. Anatomie, vol. xiv. (1877), pp. 73-93.

ii " Discoverj- of a new Anatomical Feature in Human Blood-corpuscles." CJiicago Medi-
cal Journal, May 15, 1868, and April 15, 1869.

nil " Contraction of Blood-corpuscles through the Action of Cold." Jfew York Medical
Journal, March, 1877, p. 244.

nil " On the Nucleus of Red Blood-corpuscles." Arbeiten der St. Petersb. Gesellach. d.
Naturf., vol. vii. (1876), p. 129. (In the Russian language.)

STBUCTURE OF COLOh'h'J) liLOOD-COUrUSCLEH. 87

muny roil c'orimsfk'.s wliat lie was iiicliiu-il to iiitt'rprot as a central nucleus, in
oonfirniatiou of tiie observations of Bottcher.* More recently, Stowell has
written a communication to corroborate Bottcher. t And Strieker has ex-
pressed the opinion that tiie nuclei of embryonal colored blood-corpuscles of
mammals persist as circular thin disks; he argues that these "disks are so
large that the body proper of the corpuscle appears on a surface view as only
a narrow zone; and that, therefore, except with high powers, the exist-
ence of a nucleus is easily overlooked ; and he asserts that, l)y means of
objective No. ir>, he has in the blood-corpuscles of man, dog, rabbit, and cat
seen the nucleus in both surface and profile views. X

On the other hand, Schmidt and Schweigger-Seidel, who repeated Butt-
Cher's early methods, using especially chloroform as he had done, failed in
finding tmclei, and suspected ojitical illusion. ^ Klebs contradicted Bottcher's
statements as to the presence of nuclei in normal mammalian red blood-cor-
puscles ; but described the occurrence of nucleated red corpuscles in blood
taken from the corpse of a child who had suffered from leucfemia, agreeing in
so far with a like observation of Bottcher. || Brunn said If that he had con-
vinced himself that the appearances produced by both of Bottcher's later
methods are artificial and optical effects, due to action of the re-agents on the
substance of the corpuscles. And, similarly, Eberhardt has come to the
conclusion that the remains after the action of different decolorizing re-agents
are not nuclei, but stromata deprived of coloring matter ; and that a forma-
tion iinmistakably a nucleus has not yet been demonstrated in adult human
and mammalian red blood-corpuscles.** "

Among other questions as to the red blood-corpuscle stated by Beale,tt he
asks: "Is it a living corpuscle that distributes vitality to all parts of the
organism, or is it simply a chemical compound which readily absorbs oxygen
and carbonic acid gases and certain fluids ? Is it composed of formative
living matter, or does it consist of matter that is inanimate ? Does it absorb
nutrient matter, grow, divide, and thus give rise to other bodies like itself, or
does it consist of passive material destitute of these wonderful powers, and
about to be dissolved into substances of simple composition and more nearly
related to inorganic matter ? "

He answers the fii'st parts of these iuten'ogatories in the negative, and
holds that it is "not living, but results from changes occurring in colorless
living matter, just as cuticle, or tendon, or cartilage, or the formed material
of the liver-cell, results from changes occurring in the germinal matter of
each of these cells." He says: "The colorless corpuscles, and those small
corpuscles which are gradually undergoing conversion into red corpuscles,

* " Bemeikungen iiber die Kerue der rotUen Blutkorperchen." Arcliiv fiir Mikrosk.
Anatoniie, xiii. 2 (1870), i). :^92.

t " Structure of Blood-cm-puscles." American Journal of Microscopy and Popular
Science, Xew York, June, 1878, p. 140.

t " Vorlesungen iiber allgemeine und experimentelle Pathologic." II. Abtheiluiig. Wien,
1878, p. 438.

i " Eiiiige Bemorkiingen iiber die rothen Blutkorperchen." Bericht der Kouigl. SacU-
sisclien Ge.sellscliaft der Wlssen.schaften, 1867, p. 190.

II '■ Ueber die Kerne uiid scheinkerne der rotUen Blutkorperchen der Saugethiere."
Virchow's Arcliiv, vol. xxxviii. (1807), p. 200.

IF " Ueber die den rothen Blutkorperchen der Saugethiere zugeschriebenen Kerne."
Archiv fiir Mikro.skopi.sche Anatomic, vol. xiv., Heft 3 (1877), pp. 333-342.

** "Ueber die Kerne der rothen Blutkorperchen der Saugethiere und des Men.scheu."
Inaugural- Dissertation der niedizinischen Fakultat zu Konigsberg. April, 1877, p. 30.

tf "Observations upon the Nature of the Red Blood-corpuscle" ; I. c, p. 32.

88 STRUCTURE OF COLOR ED BLOOD-CORTUSCLES.

are living, but the old red corpuscles consist of inanimate matter. They are
no more li\iiig than the cuticle or the hard, liorny substance of nail or hair is
living."* He therefore denied the contractility and amceboid movement of
colored blood-corpuscles.

Klebs was the first who accorded them life and contractility, t He did this
because, on preventing evaporation and raising the temperature of blood, he
noticed, aside from motion of the corpuscles, the protrusion and retraction of
knobs, and the formation and disappearance of scallops. But though the
correctness of his observation was not doubted, his inferences were strenu-
ously contradicted by Rollett and others, t Lankester observed " amoeboid
figiires" when colored blood-corpuscles had been subjected to the action
of dilute ammonia and acetic acid, of which he says ; $ "The behavior
of these corpuscles under alternate weak ammoniacal and acid vapors
furnished a very curious parallel to the movements of amoeboid proto-
plasm, and a careful consideration of the phenomena may throw some
light on the nature of protoplasmic contractility." Bottcher admits
the possibility of vital contractility, but thinks it cannot be compared
to that of colorless blood-corpuscles. || Brucke,!! also, admits cautiously
this possibility. Preyer** uses many qualifying expressions, such as "only
in part," " under certain circumstances," " in some degree," "temporarily,"
"at certain times." He observed active form-changes of red corpuscles
in extravasated amphilnan blood, examined in the moist chamber, which led
him to the conclusion that " the substance of these corpuscles consists of dis-
solved coloring matter and a colorless material (protoplasma) which, both
when still in connection with the coloring matter and when fi-ee from this,
shows imder certain circumstances phenomena of contractility similar to those
observed in many lower organisms." He adds : " As a rule it evinces no con-
tractility, and constitutes, as a modified protoplasm, the stroma of !\niphibian
blood-corpuscles." tt Max Schultze, who denied the contractility of red blood-
corpuscles of man and mammals (although when subjected to a very high
temperature — fifty to fifty-two degrees C, nearly enough to kill them — he
saw protrusions and detachments of portions), admitted that the red blood-
corpuscles of very young chicken-embryos are contractile, it Friedreich §$
observed in an enfeebled anaemic patient polymorphous red blood-corpuscles,
with active though very slow form-changes, which he could not but interpret
as the result of contractility. In the post mortem blood of a woman who had
been leuciemic he saw similar polymorphous corpuscles ; and in a case of
albmninoiis urine he repeatedly observed colored blood-corpuscles from which
minute portions became constricted and separated, as well as those which

Ibidem, p. 43.

t Ceiitialblatt fiir iiipdiziiiische Wissenscli., 1863, No. 514, p. 851.

X For the views of Rollett, Max Schultze, Kiilme, etc., see "Strieker's Haudbucli," cit.,
Leipzig (1869) editiou, p. 287 ; American reprint (1872), p. 286.

i Op. c, p. 378.

II Archiv fvir Mikr. Anat., vol. xiv. cit. p. 91 ; translated in Quarterly Journal of Micro-
gcopical Science, Oct., 1877, p. 391.

H L.c.

** Op. c, p. 417 ct seq.

tt Ibid., p. 440.

tt Vevlian<llunffen cler Niederrlieinisehen Gesellscliat't liir Natur unil Ileilkiuide in Bonn,
am 8 Juui, 1864 ; Berliner Kliiiische "Wocheuschrift, 1864, No. 36, p. 358.

§? " Ein Beitrag zur Lebeusgeschichte tier rotheu Blutkijrperclieu." VircUow's Archiv,
vol. 41 (1867), p. 395.

STltrCTVlil': (iF lOLORlll) nLOOD-l'Olil'rSCLKS. 89

exliibitt'tl iiiiKpltoid protrusion iind retraction of short Muiit ju'ojt'ctions,
whi'n«tiy a slow locomotion nl' tin- cnrimsclc was acconiplislicd. He aHsumed
that tlii« contractility which the colorless corpuscles possess in sohifjh a dep^-eo
is jireserved in uiidiniinished strent,4h in the reil corpuscles in certain patho-
lofjical cases. Accordiuf^toCliiirlton Bastian,* red blood-coiiiuscles leave under
certain circumstances the vessels hy virtue of active am<L'bohl movements;
and he thinks it would he well if "the attention of future observers should
be directed to these ])eculiarities, and to the particulars above mentioned, in
order to (h'termine more certainly than has yet been done how far amfcboid
movements and contractions do take place in the much-examined and much-
writ ten-about red blood-corpuscles."

Ijieberkiihn observe<l in the red coiiiuscles of salamandra and pike's blood
active protrusion and retraction of bead-like processes. He also saw move-
ments of granules or small molecules in the interior of the red blootl-corpuscles
of living frog embryos. t

Fal)er, t in addition to his own observations of contractility and si)ontane-
ous locomotion of colored blood-corpuscles in albuminous urine, — phenomena
which continued to be manifested for a longer time in colored than in colorless
corpuscles, — has given a rather complete account of the literature of these
phenomena, including the reports of diapedesis observed by Virchow, Strieker,
Cohnlieim, Prussak, and Hering. The observations of amoeboid movements
by Bastian (just cited), Owsjannikovk^,^ Winkler,|| and Brandt H seem to have
escaped him; Arnold's experiments concerning diapedesis,** and Belfield's
observation of emigration of certain small-sized red corpuscles of the frog, ft
were published more recently. Since the publication of Faber's article, fur-
thermore, Koramelaere has described amoeboid movements of colored l»lood-
corpuscles ; t+ Brandt ^Si^S has spoken of the peculiar forms of the red blood-cor-
puscles of sipunculus and phascolosoma referable to amoeboid movements,
and of the fact that occasionally in the temperature of an ordinarily warmed
room considerable movements are accomplished ; and Schmidt has observed
spontaneous motion (expansion and contraction) in a fresh colored blood-
corpuscle of amphinraa in one instance, |||| and in those of man in a number
of instances. He reports that he had witnessed the phenomenon in the col-
ored blood-corpuscles of man as early as the sunmier of 1871. He says:
"In examining a specimen of human blood, and whilst my attention was
directed to the colored corpuscles as they were carried along by a moderate
current of the liquor sanguinis under the covering-glass, I noticed on some of

* " Passage of the Eed Bliio(l-cori)U8cles through the Walls of the Capillaries in Mechan-
ical Congestion." British Medical Journal, May 2, 18(58, pi). 425, 42G.

t " Ueber Beweginigscrscheiuimgen der Zellcu."' Schriftcii der <4('sell8chaft zur Bcfiirde-
rung der gesainmten Naturwissenschaften zu Marburg, vol. ix. (1870), p. 335.

t " Ueber die rothen Blutkiirperchen." Arcliiv der Heilkuude, xiv. (1873), pp. 481-511.

§ Op. cit., p. 503.

II "Textur, Structur, unil ZelUeben in den Adnexen des Menschlicheu Eies," Jeua, 1870,
p. 33.

H " Anatomisch-hist. Untersuchungen iiber A. Sipunculus nudus, L." Memoires di-
rAcadeiiiie Iiiiperiale des Sciences de St. Petersbourg, vii. Serie, t. xvi.. No. 8.

** Loc.cit.

tf "Kniigration in Passive Hypera?mia." American Quarterly Microscopical Journal,
October, 1878, p. 39.

tt " De la Deformation des Globules Rouges du Sang." Bruxelles, 1874, p. 47.

a In a foot-note to his " Bemerkungen iiber die Kerne der rothen Blutkorperchen," I. c,
pp. 391, 392.

||||0;;.c(7..p. <;7.

90 STBUCTURE OF COLORED BLOOD-CORPUSCLES.

them the projection aud immediate withdrawal of minute, conical, thorn-like
processes, whenever one blood-corpuscle came into the vicinity of another,
'\\'ithout, however, actual contact. It seemed almost as if one corpuscle were
attracting or drawing out the thorn-like process from the surface of the other.
In other instances, however, I observed the shooting forth and quick with-
drawal of these ijrocesses from the margins of corpuscles not in close vicinity
to others. As these processes appeared at the marginal surfaces of the blood-
corpuscles, before the latter had come in contact with other of their fellows,
I naturally regarded the phenomenon as one of spontaneous motion, mani-
fested by the colored blood-corpuscle. But as in most instances the phenom-
enon was observed in corpuscles passing near each other, I was inclined to
attribute it to a certain power of mutual attraction, residing under certain
conditions in the colored blood-corpuscles. Having taken the precaution of
slightly warming the glass slide before jjutting the blood, quickly taken
from the vessels of the skin of a \agorous young man, upon it, and the tem-
perature of the surroiinding air being ninetj'-six degrees F., or even more, at the
time, I also considered a certain amount of heat, at least ninety-eight degrees
F., as essential to the manifestation of the phenomenon. This view, how-
ever, proved to be erroneous, as I shall show directly. Although I have wit-
nessed this phenomenon on blood-corpuscles when in a state of rest, it
nevertheless is more fi-equently observed on blood-corpiiscles in motion, as
when they are caiTied along by a current arising in the specimen under the
covering-glass, and resembling in character the cuiTentin the cajjillary vessels.
With this vdew, the drop of blood should be thinly spread upon the glass slide,
and quickly covered with the thin plate of glass. TiTiile the blood-corpuscle
is projecting the thorn-like process, its body elongates, resembling a uni-
polar cell, but with the withdrawal of the process generally assumes its
original round form ; bipolar or lemon-shaped corpuscles are also very fre-
quently met with in specimens of human blood. The same pi'ocess is also
observed when the margins of two corpuscles actually touch each other very
slightly, and then slowly separate again. While separating, the thorn-like
processes will be cb'awn out at the exact place of contact, and either remain
pennanent or disappear again after the separation has taken place.

" That the normal heat of the human blood is not essential to the manifesta-
tion of spontaneous motion in the colored corpuscles, I discovered during the
past winter, while repeating my examinations of the structure of these bodies.
I then witnessed the phenomenon above described, without having warmed the
glass slide and covering-glass, and at the temperature of a moderately warmed
room. However, I observed a colored corpuscle of a constricted form, similar
to a figure of eight, slowly expanding, and finally resuming its original round
form.

"From this we may conclude that the colored blood-corpuscle of man pos-
sesses not only a certain inherent power of contracting its body, but also of
resuming its original form by a subsequent expansion, a characteristic
property of the living protoplasm enabling the colored coi-puscle to manifest
spontaneous motions, though not to so great an extent as is seen in the color-
less."*

In his ''General Conclusions and Summary," Lankestert says that the
•\dscid mass constituting the red blood-corpuscles of the vertebrata " consists

* Op. cit.. pp. 113-115. t pp. cit.. p. 386.

STlillTlUE OF COLOUKl) BLOtU) COUP lUCLKS. 1)1

of (or rather yields, since the stato of combination of the components is not
known) a variety of albuminoid and other bodies, the most easily separable of
which is luemoglobin ; secondly, the matter which segregates to form Robert's
macula ; and thirdly, a residuary stroma apparently homogeneous in the
manmialia (excei)ting so far as the outer surface or pellicle may be of a differ-
ent chemical nature), but containing in the other vertebrata a sharply defin-
able nucleus; tliis nucleus being already differentiated but not sharply
delineated during life, and consisting of (or separal)le into) at least two com-
ponents, one (paraglobulin) i)recipitable by CO2, and removable by the action
of weak NH3 ; the other pellucid and not granulated by acids."

A residuary stroma, such as Lankester here speaks of, seems to have been
fii'st recognized by Nasse, who said* that the red blood-corpuscle "consists
of a basis tissue, insoluble in water, which is penetrated by a red substance,
probably tlissolved, or at least in water easily soluble (the red coloring matter
of the blood), and some water, and within which there is an aggregation of
solid granules not connected with the coloring matter." Rollett, t also,
assumed that a stroma or matrLx enters into the structure of the colored
elastic extensible substance of the red blood-corpusele, to which the form and
the peculiar physical properties of the corpuscle are due. This stroma is,
however, accoriliug to Bottcher, an artificial product, " nothing more than a
residue of the colorless part of the red blood-corpuscles, varying much in
form and extent, which remains after the dissolution of the original structural
relations." } Briicke considered the most probable interpretation of the forms
of colored blood-corpuscles, based on theii- appearances after the addition of
boracie acid, to be the existence of a porous mass of motionless, very soft,
colorless, hyaline substance, which he calls oeeoid, in the interspaces of which
is imbedded the living body of the cori:)uscle ; which body he calls zooid, and
which consists of the nucleus (where that exists) and all the remaining part
of the coi"puscle containing the hsemoglobin. ^ But Rollett insisted that the
forms on which Briicke based this interpretation are products of decompo-
sition. II Strieker agrees with Briicke as to the existence of the oeeoid, but
separates, in oviparous corpuscles, the remaining portion into nucleus and
body. H Of the thi-ee views thus presented, Lankester gives, after Strieker,
the following tabrdar statement : **

' Stroma. ? According to

Coloring matter. ^ Rollett.

Red blood-corpuscles f'^'^f = ^^f ^r part of stroma i According to
„ . ^v • • Zooid = rest of stroma plus liae- > T3„-„i,r^

of ovipara, divisi- j ^.oglobin. ^ S

^^f^^'^^^^=^^oi^- I According to

I Body=zooia minus nucleus. > Strieker

I, Nucleus == zooid minus body. j

ble into

* " Blut." E. Wagiier'8 " Handworterbucli der Pliysiologie." Braunschweig, 1842, vol. i.,
p. 89.

t " Versnche und Beobaclitungen am Blute." iloleschott's I'ntersucliuugen, ix. ; also
Sltzungsbericlite der Wiener Akademie, vol. xlvi., Div. 2 (1862), pi). 65-98; aud Strieker's
" Haiidbucli," cit. Leipzig edition, 18C9, p. 295 ; American, p. 28-1.

t Op. cit., Arcliiv fiir Mikroskopische Anatomic, p. 90, translated in Quarterly Journal of
Microscopical Science, October, 1877, p. 390.

S"Ueber den Ban der rothen Blutkorper"; Sitzung.sberichte der Wiener Akailemie,
vol. 1\-1., Div. 2 (1867). p. 79.

II " Ueljer Zersetzuugsbilder der rothen Blutkorperchen " : Vutersuchinigen aus dem
Institute der Pliysiologie und Histologie in Graz. Leipzig, 1870, p. 1.

'y " Mikroehemische Untersiicliungen der rothen Blutkorperchen"; Archiv fiir die ge-
sammte Physiologic des Mensclieu und derThiere (Plliiger's), vol. i. (1868), p. 592.

** Op. cit. in a foot-note to p. 374.

92 STRUCTUIiE OF COLORElJ BLOOlJ-COIiFUSCLES.

If it had not been for the deserved eminence in other respects of the three
investigators, Rollett, Briieke, and Strieker, these notions of the structure of
colored blood-corpuscles would proba>>ly never have attracted any attention.

Laptschinsky * considered colored corpuscles to consist of two kinds of
substance, — viz., one which appears smooth, soft, extensible, assumes mostly
a roundish foi-m, and altogether possesses some if not all of the proper-
ties of the so-called stroma ; the second, visible under the microscope
only when through the action of different re-agents it is precipitated,
or swelled, or both. It is this second substance which, on staining, takes up
the coloring matters, and, by sex^arating in the interior of the corpuscle from
the first substance, or protruding from it, gives rise to the various shapes
observed. At present it cannot be determined in what relation these two
substances stand to each other previous to the precipitation of the stainable
portion. The separating the blood-corpuscles into the two substances men-
tioned is brought about by various external influences.

In amphibian, i. e., frogs' and salamanders', red blood-corpuscles, Hensen,
Bottcher. Kollmann, and Fuchs have seen a net-work; and although they
have failed to interpret it correctly — as is evident from the context of their
descriptions — I beg to call special attention to their observations.

Hensen ascribed to the corpuscle the possession of protoplasm accumulated
at the nucleus and at the inner surface of the membrane ; the two being
connected by delicate radiating filaments, in the spaces between which the
colored cell-liquid lies.t

Bottcher, from his observations, "inferred that around the nucleus of the
amphibian blood-corpiiseles a mass of protoplasm is collected, which radiates
in the form of filaments into the homogeneous red substance. . . . The pro-
toplasm aj)pears sometimes collected uniformly round the nucleus, at other
times it is accumulated more to one side of it. It is either provided with only
a few processes, or is arranged round the nucleus in the shape of an elegant
star, whose points extend to the margin of the corjmscle, or else it forms
round the nucleus a peculiar lobed figure. Very often it appears beset on one
or all sides with fine, hair-like processes. Then, again, it may represent a sort
of net-work, which either appears separated from the less darkly colored cor-
tical layer and more contracted, or else it throws out into the cortex innu-
merable very fine rafliating filaments, so that its processes approach the
extreme periphery of the blood-corpuscles. In this case, therefore, the whole
blood-corpuscle is permeated by a net-work of fine filaments." t

According to Kollmann, the membrane incloses a net-work of delicate
slightly granular albumen threads. These in their totality constitute the
stroma, and in the small spaces between the threads of the stroma lies the
haemoglobin. The soft, elastic albumen threads are stretched between mem-
brane and nucleus. Only by a certain degree of their tension is the charac-
teristic form of the blood-corpuscle possible. The haemoglobin in the meshes
coimteracts excessive shortening of the threads. $

Fuchs expresses himself similarly as to the net-work of fibers emanating
from the nucleus, and going to the peripherj' of the frog's red blood-corpuscle.

* " TJeberdas Verlialten derrothen Blntkiirperchen," loc. cit.. pp. 178, 174.
t "Untersuchuntcen," I. c, p. 261.

t " On tJie Minute Structural Relations of the Red Blowl-con>u.scle.>i." Quarterly Journal
of ificrogcopical Science, Oct., 1877, pp. .SH8-390.
'i "Bau (ler rotlien Blutkiiri'eiclien," '. c, p. 482.

^sThTcrr/fh' or coi.o/n.n iiLooD-coinTscLKs. 9:;

He adds tliat the not-work f^ivcs tlie c'()i}iusclc its sliupo, and fixates tlie
nneh'us in the center. Deatli of tlie eorpusele ]>roduc'»'S first eoa^uhilioii,
afterward li(|uefaetion of tlie fibers of the net-work. Whenever tlie fibers are
eoajjuhited tiiey are shortened, and ]irodnee indentations at tlie surface by
tlrawinj; npon the points wliere they are attached ; when the shortening I)ro-
ceeds too far, the fibers are torn off from the membrane, and in fjoth cases of
shorteninfj there are places at the snrface which look protruded. Li(iuefac-
tion of the fibers is assnnied when the corpuscle has a vesicular appearance,
when it seems to contain a semi-fluid jiiass in which the nucleus may take any
position, and from which it sometimes exudes, proving in exuding the exist-
ence of a membrane as already described.*

Sclimidt seems to have seen something like an an-angement of filaments,
but, if so, has misinterpreted it entirelj'. He has reported obsei-ving in V)lood
of amphiuma treated fii'st with^water under the microscope, and then with a
very weak solution of chromic acid (strength not ascertained), "a series of
fine lines, radiating from tlie periphery of the nucleus through the protoplasm
to the inner surface of the membraneous layer of the blood-corpuscle." He
remarks : '' Now this pietiu-e w'ould almost seem to corroborate the theory of
Hensen, as well as that of Kollmaun ; the fine double lines representing the
filaments, which they suppose to radiate from the nucleus to the enveloping
membrane. But this is not tlie case ; for a closer examination reveals that
these lines represent nothing but fissures in the protoplasm, which appears to
have assumed some form of crystallization. This becomes more evident by
observing some of these fissures deviating fi'om their course, and giving rise
to subordinate branches." t He has also reported a somewhat analogous
appearance in the colored blood-corpuscles of the f^'og, both fresh and treated
with the same re-agents. This he explained by contraction of the interior
mass. He says : " The protoplasm in such a case retracts upon the nucleus,
which it completely suiTounds, while the membraneous layer appears isolated,
manifesting itself by a double contour. And again, if the same process should
take place without entirely separating the protoplasm from the membraneous
layer, but leaving at certain small points a union between the two parts, the
result must be the production of a number of filamentary processes, arising
from the main bidk of the protoplasm, and passing to those points of the
membraneous layer." t

Kneuttinger considered the two surfaces of the biconcave disk of blood-
corpuscles to be connected at the place of the depression by protoplasma
threads ; if these tear, the biscuit form changes to a sphere. §

According to Ki-ause, the red blood-corpuscle con.sistsof: 1. A colorless
stroma foi-med by a solid albuminous matter aiTanged into radial fibers, and
2. Ha?moglobin, which is a colored fliud albuminous matter lying in the
interspaces of these fibers. ||

Lieberkiihn has found that the free nuclei of red blood-corpuscles of
salamanib'a and tritons (the blood having been kept for some time in
colored glass tulies) consists of two substances, of which one foiTus the

' O)). cit., i>. 95.

t Op. cit., p. 72.

tllji(l.,v. 10(i.

i •' Zur Hi.stolofrif iles Bliites." Wurzburj;, 18G5, p. 22.

II " Allgemeiiie iiml Mlkru8koi)i.scbe Auatoiuie," \i. 325-334.

94 STRUCTURE OF COLORED BLOOD-CORPUSCLES.

envelope and septa or threads passing? more or less regularly through the inte-
rior, the other being contained between these septa.*

In the nuclei of colored blood-corpuscles, Biitschli, W. Flemming, and Klein
have repoi'ted the existence of a net-work, viz. :

In the nuclei of red blood-corpuscles of frog and newt, Biitschli observed
fibrils, with gi-anular thickenings, traversing the nucleus and passing to and
connecting with its envelope. t

Flemming saw a very delicate and dense net-work of fibers pervading the
interior of the nucleus, and attached to the nuclear membrane in many so-
called cellular elements of the bladder of eurarized salamandra maculata.
He inferred that the net-work is present also in the nuclei of the red blood-
corpuscles, though he did not see it there, t

Speaking of some capillary blood-vessels of a newt, Klein said: "Some
such capillaries contained blood-corpuscles, and the nuclei of these showed a
very distinct net-work." $ Also : " The examination of the nuclei of fresh
epithelium of frog, toad, or newt, the nuclei of fi-esh colored corpuscles of
these animals, especially of toad, with a Zeiss's F lens, or a Hartnack's
immersion. No. 10, reveals fibrils in the nucleus, and also shows that the
' gi'anules' are due to the twisted or bent condition of them."

III.

The method employed in my investigatiou, viz. : treatment of
fresh blood with solution of bichi'omate of potash, and examina-
tion with high magnifying power, has revealed certain appear-
ances as the structural arrangements of colored blood-corpuscles.
Do these arrangements exist in the living corpuscle, or are they
artificial productions of the re-agent ?

Dilute solutions of bichromate of potash and Miiller's fluid are
known as the best preserving media for the most delicate animal
structures : nervous tissue, the eye, embryos, etc., are kept in
them unchanged for any length of time. In the fecundated
chicken-egg of only twenty hours, placed in such a solution, the
heart, but just formed, has been known to continue for a time
to beat. Rollett has investigated the influence of bichromate of
potash on protoplasm, and found that no alterations were pro-
duced. In my series of observations, the weakest solutions (ten
per cent, saturated solution or less) produced no paling of the
colored corpuscles; while, on increasing the strength up to a

* Loc. cit.

t " Stiirtien iiber ilie ersten Entwickelungsvorfriinge tier Kizelle, die Zelltliciluiig uud
(lie Conjugation der Int'nsorien." Abhandluugen tier Seuckenbeigischen Natuiforschendeu
GeseUschaft, vol. x., Heft H, i (1876), p. 260.

i " Beobachtnngen iiber die Beschaffouheit des Zelll<ernes." Arcliiv fiir Mikioskopisclie
Anatomie, vol. xiii. (1876), p. 693 ct scq.

? " Obseivations on tlie Structure of Cells and Xuelei." Qnartci-lij Juiinial of Micro-
scopical Science, July, 1878, p. 337.

II Ibid., p. 332.

STJirCTlli'h' or ('oLOlil'J) IlLooD-COUrUSCLES. i).")

eertiiin jtoiiit, pjilinii occurred in an increasing deforce, and a
niori)li<)loiiical s(iiictni-c l)ccainc visible at the same time that the
nninifestations of life (contraction and anitt'l)oid movement) con-
tinued. From this we certainly may infer that the re-ap:ent has
not altered, at all events not seriously impaired, the livinj^ matter ;
and when we find that the structural arranjji^ements thus revealed
are the same as those demonstrable without re-agents in other
li\anf^ matter, the inference that they were preexisting, and not
artificially ])ro(luced by the re-agent, becomes a certainty.

The knowledge of the structure of colored blood-corpuscles
will not enable us to solve all the problems regarding their
nature ; but some questions are answered pretty conclusively by
my investigation.

The colored blood-corpuscle is not a cell in any proper sense
of that word, Init, like the colorless coi-puscle, is an unattached
portion of the living matter (bioplasson) of the body. Broadly
speaking, the essential difference l>etween the two kinds of cor-
puscles is the presence of haemoglobin, using this term to desig-
nate the substance or substances — no doubt chemically very
complicated — constituting the coloring matter under all the
varjdng physiological circumstances.

In size, human colored blood-corpuscles vary so much, that
claims to be able to distinguish them by their size from certain
other mammalian colored blood-corpuscles are inadmissible.

The colored blood-corpuscle has no separate investing mem-
brane ; nevertheless, the outer portion, essentially like the inner
substance forming the net- work, may be considered to be differ-
entiated from the latter, especially at the periphery of the disk,
where it constitutes an encircling band of uniform thickness,
or occasionally of a wreath-of -beads appearance. In the colored
blood-corpuscles of the lower classes of vertebrate animals there
is usually a nucleus to be seen, which is not the case, as a rule, in
those of man, and other mammalians ; but there is in the interior
of these an accumulation of matter occasionally met with, which
may be interpreted as a nucleus.

In the communication to the Vienna Academy, in 1873,
Heitzmann demonstrated the existence of a net-work in amcebae,
blood-corpuscles of astacus and of tritou, human colorless blood-
corpuscles and colostrum cor2)uscles ; and, from direct observa-
tion of the changes in the reticulum during the contraction of
the living body, announced that the substance constituting the
net-work is itself the living matter or bioplasson — /. <'., ''the

96 STRUCTURE OF COLORED BLOOD-CORPUSCLES.

nucleolus, the nucleus, the granules with their threads, are the
living- contractile matter proper.'' Aside from some conditions
which do not here concern us, he descri])ed and illustrated three
states of the net-work — viz., that of rest, that of contraction, and
that of extension.

A fourth state of the hving matter is assumed (hypotheticaUy)
by the same investigator, to account for the formation of a flat
layer of living matter, such as forms the walls of a vacuole, the
membrane of a nucleus, or the outer layer of the whole bioplas-
son mass.

Heitzniann beheves that each of these states may at any time
change into the other — /. e., that the net-work may from the
condition of rest be transformed into that of contraction, or
of extension, or of flattening, and from each of these into
either of the others. At all events, there may arise in the
bioplasson body a vacuole having a continuous thin wall, and
containing lifeless fluid and detached particles of the living
matter. Or, a bioplasson mass may take into its interior foreign
bodies l)y forming around them a cul-de-sac, which then opens
toward the center and closes at the periphery, and the net- work,
rent during the process, reestablishes itself. Again, a bioplasson
body, which by flap or knob protrusion and separation has lost a
portion of its substance, as well as the portion detached, may
become rounded off — the rui)ture at the place of detachment
healing in each case without loss of Hfe. And further, two bio-
plasson bodies may coalesce, and a portion of the periphery of
each be transformed into the uniting net-work.

By adopting these views, and applying them to the living
matter of colored blood-corpuscles, we may explain the changes
which they have been observed to be subject to. What are the
changes that occur on the addition of a 40 per cent, saturated
solution of bichromate of potash ? I have described indentations
and protrusions which either persist or are leveled again ; pro-
trusion of knobs, either pedunculated or sessile, which sometimes
are so numerous that they surround the body of the corpuscle
like a wreath ; decrease of the size of the main body by detach-
ment of knobs ; appearance of net- work structure, most marked
in the corpuscles which have not lost much of their substance ;
vacuolation of corpuscles, and transformation of many of the
portions detached into vacuoled globules which increase in
size ; finally, change into faint, almost structureless disks, the
so-called '' ghosts.*'

srnrcrrRi-: of cojjjjikj) lii.ooD-coiwrscLKs. \)i

The rc^niliir rosette, stellated, and th<)i-ii-ai»i>le sliai)es are
euused ])V a unifonii ('(Hieeiitric eontraetioii <»t" the livin<; matter ;
— the fiiiid in the interior, bein^ pressed toward the outer layer
between the points of attaehnient of the threads, will prodnee
a biilfiriii^r oiit at the })erii)herv. Irre^idar conti-actions of the
livinj; matter will <i:ive rise to irrej^ular flaps at the periphery.

An indentation is due to loeally limited eontraetion of the
net- work in the interior of the eorpusele. Contraction of the
living matter at one part of tlie ])eriphery will l)rin<j: about a
protrusion of a flap at another, the fiaj) ])ein<i: bounded by the
outer layer of the corpuscle.

Se<;mental contraction of the net-work will pj-oduce a rupture
of the outer layer of the corpuscle, with i)rojection of a pedun-
culated granule or knob, formerly a part of the interior net-work.
Continued contraction will be followed by the rupture of the
pedicle and the production of either so-called detritus or small
gri'anules, or when the protruded knob is larger, or has become
swelled, of a pa]e-gra_\dsh disk.*

Lastly, a large amount of the net- work having been separated
from the parent body, the latter becomes transformed into a pale
disk, in which no traces of a net- work, or but very indistinct
ones, are visible, a so-called ghost.

At every stage of the protrusion of either flaps or pedunculated
knobs or gi-anules, the living matter may be overtaken by death,
and the contraction become fixed by cadaveric rigidity. It may
perhaps be worth while to notice that irregular contractions have
a somewhat greater tendency to such permanency than regular
ones ; these more frequently \nelding, by relaxation of the net-
work, or reestablishment of the state of rest, at impending death.
But in the blood-corpuscles kept for over two years in bichromate
of potash, all the described forms can be observed just as well
as in freshly made specimens.

* The peculiar coi-puseles believed to be characteristic of sj^philis by Los-
torfer, and proved by Strieker to be present in the blood of individuals broken
down by that and various other diseases, are nothing but such disks — /. e.,
portions of the colored blood-corpuscles protruded fi-om the interior, detached
and more or less swelled. As persons in low states of healtli have a relatively
small amount of living matter in the same bulk, or, in other words, only a
delicate net-work within the bioplasson body or plastid (the so-called " cell"),
such a net-work suspended in a relatively large amoimt of fluid can much
more easily contract and bring about a rupture of the outer layer, than in the
case of healthy persons, within whose plastids there is relatively less room for
contraction to take place.
7

98 ORIGIN OF COLORED BLOOD-CORPUSCLES.

The reason why the corpuscles of the smallest size do not
chang:e in the sohition of bichromate of potash of medium con-
centration, is, perhaps, that, l)ein<j: compact masses of living mat-
ter in which the htemoj^lobin is not as yet accumulated within
meshes, the solution does not reach and cannot extract the
haemoglobin. These small globules are probably intermediate
stages of development of colored blood-corpuscles, or the so-called
haematolilasts of Hcitzmanu * and of Hayem.t

The Origin of Colored Blood-corpuscles. In 1872, | at a time
when I was ignorant of the structm-e and differences of bio-
plassou, according to its development, and consequently adhered
to the cell-theory, I made the following statements :

Formafioii of Blood from Cartilage. In a horizontal section
of the condyle of a femur of a recently killed dog, several weeks
old, we recognize, upon adding a cb'op of a one-half per cent,
solution of chloride of sodium, ^^'ith moderate powers of the
microscope, two kinds of cartilage-corpuscles, — Hr.^t : large, pale
gi'anular, distinctly nucleated cartilage-corpuscles; and second:
smaller shining, yellowish, indistinctly granular corpuscles,
devoid of nuclei. There are transitions between these two kinds.
Still more marked is the difference in sagittal (antero-posterior)
sections of the cartilaginous epiphysis of the same dog. Near
the articular sui'face, the corjjuscles, closely arranged, look
uniform ; but the nearer we come to the diaphysis, the more
marked is the difference between the pale and the yellow, shining
corpuscles. The glistening substance is often found in a crescent
shape around the pale granular, or it occupies the center of the
latter in the shape of a globular or irregularly angular body.

Close to the border of the calcified basis-substance, the
difference between the two kinds of cartilage-corpuscles is very
marked. In a cavity of the basis-substance we often find the
shining, coarsely granidar substance characterized by thorny
offshoots, and surrounded by a pale, granular zone, between
which and the basis-substance there is an apparently structure-
less rim. Solution of chloride of gold renders the finely granidar
bodies pale violet, whereas the coarsely granular ones assume a
dark violet color, retaining their luster.

* " Studien am Kuochen und Kiioi'pel." Med. Jabrbiicher, 1872.

t " Suv I'Evolutioii des Globules rouges daus le Sang des Vertebres."
Cornpt. rend. Aead. des Sci., Nov. 12, 1877; Idem. See. de Biologie, Nov.
24, 1877. " Sur TEvolution des Globules rouges dans le Sang des Auimaux
sup^rieurs." Compt. rend. Acad, des Sci., Dec. 31, 1877.

t " Studien am Knochen und Knorpel." Medic. Jalu'biicher, Wien, 1872.

(HU(iis OF coLoh'hn ni.()()i)-(()i{i'rscij':s.

\)\)

The olilor an iuiiiual (do?;", cat, oi* ral»l)it) we cxaiiiiiH', the
Ihiinicf we find its articnlar <*artila}^(', and Mjc U'ss of shining,
coarsely <;ranulai- coi-puseles ; iu the cartilage of a very old
dog such corpuscles were cntii'i^ly wanting — only ])ale gi-annlar
nucleated were j)resent.

On the calcified ))()rder of the articular cartilages of a young
rabbit, I found large spaces in the narrow calcified l)asis-substance,
which were partly filled with a colorless, finely granular proto-
plasm, and their centers exhibited the glistening su1)stance. In
the large spaces below these, groups of bright lumps of difter-

Fir;. L' 7.— Condyle of Femur of a Young Rabbit, at the Border of
Calcificatiox of the Diaphyseal Cartilage. Sagittal Section.
[Published in 1872.]

CC, t-aitilajje-corpuscles, filling the spaces of the calcified basis-substance, CA ; changing
in one level into liiiniatoblasts, X, and below this level into medullary corpuscles, P. The
spindles in the middle of the medullary spaces are forniinir blood-vessels. Magnified 800
diameters.

100 ORIGIN OF COLO It ED BLOOD-CORPUSCLES.

ent shapes were present, which had the appearance of having
originated by the splitting- np of larger lumps. (See Fig. 27.)

As the shining, solid corpuscles exhibited stages of develop-
ment advanced to the formation of nearly perfect red blood-
corpuscles, I considered them as juvenile forms of the latter, and
proposed for their designation the term " hannatoblasts." I

concluded that a
part of the carti-
lage-corpuscles, or
:^ a portion of the

^ \ fl^fe body of such a

; , *li: corpuscle, had be-

. come transformed

into ha?matoblasts.

p^ Formation of

'•- Blood in Inflamed

1 ^ Bone. In speci-

'^^^^h^" ■H^K^:-'' mens obtained

Fig. 28.— Bone-corpuscles from the Compact from a dog s tibia,

Portion of a Dog's Tibia, Injured with a which, eight days

Red-hot Iron. Eighth Day of Inflammation, before the death of

Chromic Acid Specimen. [Published in 1872.] the animal, was

The number of blood-corpuscles varies in A. B, C. Magnilletl pui'DOSClv iuiurcd
800 iliaiueters. ■ -, \ t ■

With a red-hot u'on,
without opening the central medullary sjjace, I found in the
bone-tissue numerous cavities, which, besides a finely granular
protoplasm, contained red blood-corpuscles. (See Fig. 28.)

The suspicion arose that the blood-corpuscles had formed
from the bone-corpuscles, which might be confirmed b}- finding
stages of transition.

Such stages were really discovered in many of the specimens.
I met in the cavities of the bone-tissue with manifold formations
of a substance the characteristics of which were : absence of a
visible structure, a high degree of luster, and a yellow color.
This substance appeared either in the shape of ledges bordering
the pale, granular protoplasm, or of lumps with fine scallops or
of glistening disks, and lastly, of corpuscles looking like red
blood-corpuscles with the central cup-shaped depression, and,
in side-view, biscuit-shaped. Lumps of this substance may some-
times be composed of coarse granules. (See Fig. 29.)

Identical formations were also found in blood-vessels. We
are justified in calling corpuscles that we find within blood-
vessels, blood-corpuscles of some kind. Now, as these corpuscles

OliUllS OF COLOltKI) IlLOOD-COlWrsCLKS. 101

do not, citlicr inside or outside of the vessels, wliieh tlieniselves
are not fnlly developed, exhibit the features of ])erfeet red Idood-
eorpuseh's, but show the most convineinji; transitions toward
such, we are eertainly justified in sayin<^ that they are stages of
deveh)pnient of colorless proto})lasin into colored (corpuscles.
We may designate such fonnations as lia'niatoblasts.

I thus saw formations also met with by \V. II. C'armalt and
S. Strieker * in the inflamed cornea of the frog and rabbit, and

\l/^Mm: ''

l<I1Iil'

TJ

"-. -.4;'-— — *-^~ L^

Fig. 29. — ILi:MATOBLASTS in Bone-corpuscles op a Dog's Tibia, Purposely
Injured with a Red-hot Iron. Eighth Day of Inflammation. [Pub-
lished IX 1 S72.]

Bright lioiiiofjL'iu'ous lumps, X' ami V, contain a few vacuoles, T', or numerous vacu-
oles, D. The shininif substance borders tlie bone-corpuscle at J/,- a fully formed re<1
blood-corpuscle at B. Magnitied 800 diameters.

could corroborate the statement of C. Rokitansky t that in
" mother-cells," when they ramify in order to produce a capillary
system of vessels, blood originates.

In 1873 (page 46), I claimed all the formations described to
l)e li\dng matter at an early, juvenile stage, from which, in turn,
liy vacuolation and reticulation, protoplasmic bodies may arise.

* Medic. Jalirbiicher. Wien, 1S71.

t Handbuch der aUg. patholog. Anatomie. Wien, 1 S4(i.

102 ORIGIN OF COLORED BLOOD-CORPUSCLES.

Lumps of living matter, however, separated from the neighbor-
ino^ formations and suspended in plasma, in blood-vessels, I still
considered as blood-formers — hiematoblasts.

The idea prevailed at that time that red blood-corpuscles
originate from nucleated, colorless corpuscles, although no other
support was found for this idea except that in the embryo there
are numerous nucleated corpuscles in the blood-vessels. All
attempts to transform colorless into colored blood-corpuscles
outside the body, l)y their exposure to oxygen gas, proved to be
failm'es. I have shown that whenever one tissue is transformed
into another, — f. i., cartilage into bone, and also in an inflamed
tissue, f. i., that of bone, — colored blood-corpuscles grow from
granules of living matter in a waj'' entii^ely different from that
supposed by other histologists.

E. Neumann* first drew attention to a difference in the
shape of the corpuscles of the medulla of bone. In the liquid
pressed out of this tissue he found colorless, granular lymph-
corpuscles and yellow corpuscles, characterized by a homogeneous
appearance, and a size only a little exceeding that of red blood-
corpuscles. He met with colored cells in the medulla of bone,
in numbers the greater the younger the individual, and inter-
preted these to be stages of transition to red Ijlood-corpuscles.
He also concluded that during life a continuous transformation
of lymphoid into red blood-cells takes place.

G. Bizzozero t found in the medulla of l)one, besides colorless
I)rotoplasmic bodies, siich with homogeneous, reddish-yellow
nuclei, and also bodies about to di\dde, which contained two
homogeneous reddish-yellow nuclei. He also interpreted these
bodies as transitions of colorless to colored cells, and came to
the conclusion that the medulla of bone was of importance in
the production of colorless and red blood-corpuscles, and
that the formations of the latter started from the nuclei of
the former.

It is obvi(nis that the formations described by these investi-
gators are identi(;al with those I had termed haematoblastic,
which oceiu' not only in the medidla of bone, but also in bone
and cartilage in the normal process of ossification. The yellow
lumps which all of us have seen arc l)y no means blood-cor-
puscles, though under certain circmnstances they may furnish
the material for the formation of blood-corpuscles.

* Ceutralblatt fiir diemed. Wissenschaften, 1868. Archiv der Heilkunde, x.
t Gazetta medica Lombarda, 18(58 and 1869.

omais OF coLoh'h'n iu.ood couitsclks. \m

Based upon rcscarclu's in (•artila<;«' and Ixnu' of ])ird8,
L. Scluint'v, in iSTd,* makes tlu' following" statements:

'' E. Neumann t has denied the new formation of red })lood-
eorpuseles on the l)order of ossifieation of tlie cartihiffe. At tlu'
same time he draws attention to Aeby, wlio ah-ead}' in iH.jS
sn<i-i;ested sueli a new fonnation. From tlu; ([notation of Aeby's
words, it foUows that he only supposed the new formation (m
the border of ossification, as his researches in this direction did
not yiehl positive results, wh(n*eas Heitzmann positively asserts
the fact of sucli a new fonnation.

"E. Neumann's reasonin«;' I cannot consider correct; he, f. i.,
could not understand that lucnuitoblasts should stain Avith
carmine, while perfect red blood-(;orpiiscles remain unstained.
Heitzmann claims that the haematoblasts are in a juvenile con-
dition of the protoplasm, from which, after certain changes have
taken ])lace, red blood-corpuscles arise. Corpuscles may react
on being stained, in a different way, in their youth and old age.

" E. Neumann, furthermore, makes a point of the absence
of nuclei in haematoblasts, assuming, as he does, that blood-
corpuscles in their juvenile condition must have nuclei, though
they are destitute of such later. My own researches may also
clear up this point.

'' E. Metschnikowf found in the impregnated and hatched germ
of fowl, at fii'st nucleated, slightly colored, and later, nucleated,
distinctly colored, blood-corpuscles, and concluded that the latter
had originated from the former. This conclusion is not fidly
justified, as it is possible that, from the same source, at first
slightly and aftei'ward deeply colored blood-corpuscles may arise
and pass into the circulation without necessarily having directly
changed from one into the other. The same reasoning also holds
good for the blood-corpuscles of mammals. If at first nucleated
and afterward non-nucleated blood-corpuscles are visible, who is
willing to maintain that the latter have originated from, the
former, and that each red blood-corpuscle must have had a stage
of nucleation ?

* "Ueber den Ossificationsproeess bei Vogeln, uiid die Neubildung von
rothen Blutkclrpercheu an der Ossiiieationsgrenze." Archiv fiir mikrosko-
pische Anatomie. Bd. xii.

t Heitzmann's " Hsematoblasten." Ai'cliiv fiir mikroskopisclie Anatomie,
November, IS 74.

+ " Zur Ent^vieklungsgeschiehte der rotlien Blutkorperchen." Virchow's
Archiv, 41 Bd., 18G7.

104

ORIGIN OF COLOBET) BLOOD-rOTiPUSCLES.

" On watching si)ecimens from the horder of ossification of a
growing chicken, we see within melted portions of the calcified
basis-substance, homogeneous, shining lumps, in club-shaped
spaces, inclosed by spindle-shaped elements. These spaces are
not connected with perfect })lood-vessels. The authors agree in
considering such club-shaped formations as the first appearance
of blood-vessels in the center of a medullary space. What are
the shining corpuscles in the interior of a future vessel ? What

else than not fully de-

^.

"Tjit

(^

yi

4V-4

veloped blood -corpus-
cles ? — therefore, hae-
matoblasts. It is re-
markable that these
corpuscles have no nu-
clei, and corpuscles
crowded in blood-ves-
sels toward the bone-
tissue, the connection
which with older
blood-vessels is not yet
evident, also want nu-
clei. Nucleated blood-
corpuscles, so charac-
teristic in birds, are
visible only in deeper
layers of the fully
formed bone-tissue. If
we admit that the
youngest medullary
formations are found
in the ossif;\4ng borders
of the cartilage, and
that in the medullary
spaces there are pres-
ent corpuscles, to be considered as blood-coi-puscles, we may
readily accept the possibility that the nucleus is not an early,
but rather a later, formation. This would agree with the state-
ment of E. Briicke, concerning the formation of the nucleus in
different other protoplasmic bodies. (See Fig. 30.)

'' The specimen illustrated above admits of but one interpreta-
tion, viz. : that in fowls the first formed blood-corpuscles, the
haematoblasts, have no nuclei; whereas complete red blood-

I

Fig. 30. — Oblique Section through the
Border of Ossification op the Condyle
OP Femur of a Young Chicken,

Tlie central medullary space is surrouudeil by tlie
calcified frame, C, of the hyaline cartUage, and in its mid-
dle there are several club-shaped si)aces containing
haematoblasts, H. In the lowest space, B, the red blood-
corpuscles do not yet exhibit nuclei. Magnif. 700 diam.

<n{i(iis or coLojn-.j) nuxtn-coKruscLES. la")

coi-jjiisclos hjive nuclei. Tlie iiuclt'us is evidently not a j-e(|nire-
nient of juvenile red l)lo()d-corpuseles.

"In t'ull-<jfrown bii-ds sueh a new formation of blood-eor-
puseles does not occur. In a pigeon nine months (^Id, the layer
of globular cartilage-coi-puscles is directly bounded by bone-
tissiu'. containing mednlhirv spaces filled with fat. The blood-
vessels of these si)aces at their upper ends, looking toward the
cartilage, are looped. The intermediate stage of ossification of the
basis-sul)stance and new formation of blood-vessels and hajmato-
blasts is absent. In still older animals, in whi(;h the layer of
hyaline cartilage is much reduced in thickness, the upper ends of
the medullar}' spaces toward the cartilage are closed by concentric
systems of lamella^ of completely formed bone-tissue."

llayem (see ])age 98) in 1877 described small shining lumps
in the fluid of l)lood, more numerous in the foetus than in the
adult, which he, I think justly, termed " haematoblasts."

Red blood-corpuscles are very early formations of the middle
layer (mesoblast) of the embryo. Probably they originate in
every part of the body wherever there is living matter, especially
in all varieties of that tissue which is exclusively supplied with
))lood- vessels, viz. : the connective tissue. Red blood-corpuscles
are produced from lumps of living matter whenever, in the young,
one variety of connective tissue is transformed into another — f . i.,
cartilage into bone. After the organism has reached full develop-
ment, the production of colored blood-corpuscles continues in
that variety of connective tissue which longer than any other
remains in a juvenile condition, namely, the lymph-tissue. This
tissue is present in large quantity in the body — the larger the
younger the individual. It exists in all mucous layers, in the
medulla of juvenile bone, in the lymph-ganglia, and in the spleen.
Unfortunately, in consequence of former misapprehension of the
nature and significance of this tissue, it bears the misnomer
"adenoid tissue." That this tissue is a source of red blood-
corpuscles during the entire life-time, will be demonstrated in the
next article.

Experimental and Microscopical Studies on the Origin of the Blood-
globules. By a. W. Johnstone, M. D., Danville, Ky.*

The objects of this paper are to give the result of a repetition of Onimus's
experiments on the " origin of the white blood-corpuscles," and to place on
record an account of an undeseribed method of development that is constantly

* " Arcliivesof Medicine," vol. vi.. Auf,'U'<t. 1881.

ion OlilGIX OF COLOBEJ) BLOOD-CORPUSCLES.

going on in the adenoid tissues. His conclusions are that the corpuscles have
sprung up de novo from the Vjlastema, and by analogy he argues that there is
a spontaneous generation going on in serum wherever it is found. As given by
Flint, these experiments on animals are as follows : The serum from quickly
drawn blisters, after ha\ing been freed by filtration, etc., etc., from all its
organized elements, is placed in bags of gold-beater's skin. These sacks are
then placed in the subcutaneous tissues of rabbits, and after a sojourn of two
or three days their serum is found to contain a variable nimiber of leucocytes.
I have repeated these investigations, and in two directions have pushed them
farther than their author ; that is, instead of the blastema, in the coiirse
of the experiments I used four different liquids, and in all cases, besides the
fluids, I examined the gold-beater's skin after its removal.

In ad<lition to the serum, I used a weak solution of chloride of sodiima in
water, a mixture of this \vith the white of an egg, and lastly the clear part of
the egg alone. The animals used were cats ; the length of experiments from
seventeen to fifty hoiu-s ; the thickness of the inclosing membranes was in
most instances one, but in two cases two, layers of the gold-beater's skin. In
all cases I examined both membrane and blastema before the introduction to
the eat, and thus made sure that no organisms were present. My results were
that in every case, except where I used a varnished membrane, I found leu-
cocytes in the blastema, and wherever they were found in the liquid, the
walls of the inclosing bag were sure to be crowded with the same organisras.

The only things that seemed to influence the number of the corpuscles
were the condition of the containing membrane and the length of time the
sack remained imder the skin. If these conditions were the same, there were
just as many corjjuscles in the solution of chloride of sodium, or the egg mixt-
ures, as there were in the serum. In the cases where the skin was doubled
after a longer time than was ordinarily employed, a few corpuscles made their
appearance in the blastema, a few were found in the inner layer of the bag,
whilst the outer one contained a great many.

From these facts we are forced to the conclusion that the corpuscles
migrated through the walls of the bags, just as they do to the interior of the
catgut ligatures that are left in similar conditions.

This, however, is only a negative land of proof, and for something positive
I wiU ask the reader's attention to my recent study of the so-called adenoid
tissue.

It is not necessary here for me to give the histology of the organs that
contain this tissue, and to repeat that in the Ij-mph-gangUa it is aiTanged into
h-mph foUicles, lymph cords, and interfoUicular striags ; in the alimentary
canal into follicles such as are contained by the tonsil, base of the tongue,
pharynx, stomach, solitary glands, Peyer's patches, etc. ; in the spleen into
the ensheathing coats of the arteries, and the so-called Malpighian corpuscles,
etc. But for our purpose, all that we need to know is that, wherever this
tissue may be, there is a stream of fluid coming into it on one side, which,
after working its way through the sponge-like mass, passes out on the other,
and eventually empties into the blood.

The two questions to which we will now address om-selves are : Whence
comes and what is the function of the "adenoid" tissue.

All histologists agi-ee that in the animal kingdom we find but fom-
varieties of connective tissue, and that they are the myxomatous, the fibrous,
the cartilaginous, and the osseous. The myxomatous connective tissue is met

ouiais OF ('()L()iii:i> j!L()()H-(()i,'i'i'scjj':s. 107

witli almost (>x<'lusiv<>ly in t lie t-arlicst stiifj^cs of dcvoloimu'iit of tlic ciiiliryonal
I'oiiiu'ctivc tissiu', and in transient fo'tal orpins, such as tlm innl)ilicai t-ord
and phuHMita. This tissue a])])ears in two varieties : first, in tlie shajje of a
I)roto{)hisniie reticulum of f^reiitly varying size, with nuclei at its points of
intersection, the meslies of which hold tlie j(dly-like mucoid Itiisis-substance
(umbilical cord). In the centers of the meshes, globular and ajiparently
isolated bodies are seen. The otlier form consists of a delicate fibrous
reticulum, haviufj oblong nuclei at the jmints of intersection, the meshes
lieing filled with single protoplasmic bodies (so-call(Ml " decidua cells" of the
placenta), or with a mucoid basis-substance with scanty bodies (derma and
mucosa of the embryo in the earliest stages).

Recent researdies have i)roved that this mucoid basis-su>>stance is not a
structureless mass, but tliat it is pierced by a living reticulum, wliich is
continuous with a smaller net-work pervading all protoplasmic formations.
As the fibrous reticulum of myxomatous tissue is a protoplasmic formation,
its fibers, too, contain a fine reticulum of living matter, which is also con-
tinuous with the fine reticulum of its neighbors. So the basis-substance, in
either its mucoid or fibrous variety, differs from protoplasm only by a chemi-
cally altered substance witliin the meshes. This substance in the protoplasm
is a liquid, in the basis-substance a semi-solid, though not strictly glue-
yielding mass.

As has been known for a long time, comparatively low powers, when
brought to bear on the adenoid tissue, demonstrate the presence of a delicate
fibrous reticulum, which at the points of intersection is generally slightly
thickened and flattened so as to present a plate-like ap|)earance.

These intersections are sometimes pro\dded with nuclei, and tlie meshes
of the net-work are alw-ays filled with lymph-corpuscles. Although these cor-
puscles are so closely packed that they often flatten each other, still each one
is generally separated from its neighbors by a narrow, light substance which
is probably liquid.

Unless the lymph-corpuscles be torn apart by mechanical injuries, such as
ciitting, washing, etc., etc., they are all connected with each other by ex-
tremely delicate, gi-ayish spokes, which traverse the intermediate substance
in all directions. A like connection always exists between the lymph-
corpuscles and the fibrous reticulum nearest to them.

Most authors claim that this fibrous reticulum of the adenoid tissue is
structiu-eless, and exhibits nuclei only at its points of intersection. This
assertion must be based on Canada balsam specimens, for it makes all minute
details fade away. My own specimens, cut from fresh lymph-ganglia, or sucli
as had been preserved in a dilute solution of chromic acid, show a well-
marked net-work in the fibrous reticulum, both in the imstained and in the
carmine specimens.

While we are on this subject of the preparation of specimens, let me say,
once for all, that if we hope to see the minute structure of this tissue, our sec-
tions must be cut from fresh or from chromic acid preparations, for alcohol or
water destroys the details. If stained at all, it should be done with carmine,
or, what is better, the one-half per cent, of chloride of gold. Tliis last-named
agent has a peculiar faculty for taking hold of the living matter of the most
minute organisms and making it stand out in a very satisfactory manner.
Lastly, I would state that glycerine seems to be the only mounting substance
now known that will j)reserve tissues absolutely unchanged.

108

OBIGIN OF COLOEEl) BLOOD- CORPUSCLES.

Reasouing by analogy, it seems that we are forced to conclude that
adenoid tissue is myxomatous, and therefore a remnant of foetal tissue. We
know that the myxomatous tissue is abundant in the embryo, and relatively
scarce in the fully developed foetus. In the adult, the vitreous body was
considered the only remnant of embryonal myxomatous tissue. To this,
however, we should add the adenoid, and thus answer our first question.

To get a better idea of this tissue, let us turn to its most minute anatomy,
and for the present we will confine our attention to its frame-work. As I

Fig. 'SI. — Lymph-ganglion of Cat.

R, myxomatous reticulum, exliibiting in its interior a delicate retionhun of living matter ;
a, granules of living matter arising from the growth of the inteiseclions of the contained
reticulum ; I', granules grown into vacuoled coiiiusckjs and intermediate stages of develop-
ment; i, full grown nucleated lymph-corpuscles: M. mesh of the myxcmiatous net-work,
tilled with lymph-coriniscles of all stages of develoi)ment. ilagnitied 1200 diameters.

have already said, in the frame-work, which looks perfectly homogeneous
under a 500, with a 1200 (immersion) we can readily recognize a delicate
reticulum piercing nearly all its fibers and plates. In some places, even
without the use of a staining re-agent, this net-work is just as plain as in the

oiiiais OF ((jij)iiKi) r.i.ooD-coui'rscLKs. lo'j

corpusdos themselves, the only difference being that its meshes are a little
wider than those in the glolmle. But the point to which I wish to draw
particular attention is that the fji-anules, at the points of intersection, varj-
very much in size. Sometimes, wiiere they are seen along the edges of broad
fibers, or in the centers of very tine ones, they give it a beaded ajtpearance.
At others they are so small that they are just barely ajipreciable. This
inequality in size is most proljably due to a gi'owth that is c«jnstantly going
on in these granules, and oiu* finding different ones at different stages of it.
(See Fig. :n.)

This process <loes not stop where the lumjt of living matter can lie called a
gi-anule, but it keeps on until it has converted it into what is known as a
corpuscle. This is accomplished by the smaller granide increasing until it
has become so large that the liber can no longer contain it without sho^ving
a slight bulging at the point where the gi-anule lies. This is what gives the
beaded appearance just referred to. But as the bead still gi-ows, it protrudes
more and more from the free sm-face of the fiber, until it has the appearance
of a small homogeneous yellowish corpuscle sticking to the side of the fiber.
The corpuscle is not separated fi-om the fiber in this immatui-e state, but
retains a connection in the shape of verj' delicate gi'a\"ish spoke-like threads,
that can be traced dii'ectly to the gi-anides within the fiber. This connection
is constant in all the different-sized coi-puscles, except the very largest, and
in all probability is the route through which the corpuscle draws its nourish-
ment. We can see no differences in these growing corpuscles until they are
about three-quarters the size of a red blood-globule. Then, however, they
seem to be divided into two classes. Whether there are two sets of fibers
that produce the different corpuscles, or how else it is done, is more than I
can say; but I am sure that, at the stage I have indicated, one set become
more highly refracting than the other, and take more and more of the char-
acteristics of a red blood-globule, which they eventually become. The others,
however, follow the coui-se that C. Heitzmann has described, as the ele-
mentary homogeneous gi-anule takes in its development into a higher grade
of protoplasm. After they reach the size I have already spoken of, a ca\T.ty
containing a small amount of liquid forms, then similar excavations show
themselves, imtil only a frame-work of the li^-ing matter is left between the
vacuoles. There are communications established between these cavities, and
the frame-work is transformed into a net-work ^sith thickened points of
intersection, which are the granules.

With tliis view of the development of protoplasm we are better able to
understand the meaning of the vacuoled corpuscles that we so often meet
with. But the different sizes of the corpuscles, the different numbers of their
granules, and the varying conditions of their nuclei and reticula. speak for
themselves. They are the different stages through which an original gi'anule
of the fine reticulum contained by the fibrous net-work is developed into a
full-grown Ij-mph-coi-puscle.

This is further substantiated by the fact that the connection, already
described, between the granule that has just passed to the outside of the fiber
and the reticulum within it, is kept up through all sizes and shapes of cor-
puscles, luitil the full-gro\vn condition is reached. Then, however, this attach-
ment is severed, and the globule passes away with the lymph stream in which
it has been bathed so long. This is true of both sets of cori)uscles, and can be
shown as well in the young red as in the white. Thus we add a new proof

110 OEIGIN OF COLORED BLOOD-CORPUSCLES.

to the old idea that a red globule is nothing but a mass of protoplasm contain-
ing ha^moglobine within its meshes ; for the elaboration of this subject I refer
to the researches of L. Elsberg.

The organs that I have used in these investigations are the lymphatic
ganglia of man, horse, and cat, the spleen of man and cat, as well as the tonsil
and thymus gland of childi'en. The charactei'istics of the adenoid tissue were
found to be the same in all, the principal differences being in the proportion
of red to white globules. In the tonsil and lymphatic ganglia, the red are
very scanty, though they can be found in most fields ; but in the spleen they
are far more frequent. In this organ, like the rest, the corpuscles are formed
by the development of the gi-anules of the net-work within the frame, and not
by budding of the endothelial plates, as claimed by some. We are now ready
to give the reason for the lymph of the efferent vessels containing so many
more corpuscles than that of the afferent, as well as to say where the few red
globules that are found in the lymph of the thoracic duct come from. The
lymph stream, as it passes through each successive ganglion, carries along an
increased number of the ftdly gTown elements that have become detached
fi'om the parent fiber, and eventually empties them into this duct, through
which they reach the blood.

In answering these questions, we are also gi%dng the function of the ade-
noid tissue, which is to produce the corpuscular elements of the blood.

It has been known for a long time that as age advances the adenoid tissue
becomes more and more scarce, and that the mucous layers and other organs
that were once so rich in it, at extreme old age present scarcely a trace. In
reality, the thymus gland may be taken as the type of the whole class. For
while their degeneration is by no means so rapid, still they all show a tendency
to follow its example. Tliis is most strikingly shown in the history of Peyer's
patches, as has been brought out by the study of tj^phoid fever. From this
we woidd conclude that a young animal is the best subject for the study of the
adenoid tissue. This I can testify is the case, for as age advances the gran-
ules of the I'eticulum within the fibers become more scanty, and the retic-
ulum itself is by no means so rich as in the early days of life. Shoidd it ever
be conclusively proved that the white blood-corpuscles share in the formation
or repair of the structures of the body, we would then have the complete
chain of their history ; for we are now sure that they represent only one stage
of a development that is going on as long as Life lasts, and I am not inclined
to believe that this stage is the highest of the series.

The conclusions that I have di-awn from these studies are :

1st. We must have more and better proof before we can believe that a
lymph-corpuscle ever arises from a blastema.

2d. That both red and white blood-corpuscles are developed from the gi-an-
ules of the reticulum of living matter within the fibers of all adenoid tissues.

.'^d. That in different organs there is a difference in the proportion of red
to white globules that are produced.

■ith. That the adenoid tissue is myxomatous, and, jn-operly speaking, a
remnant of foetal life.

5th. That this tissue is stored-up material, from which the lilood-corpuscles
are made throughout life.

Gth. That it is highly probable that the exhaustion of this nuiterial plays
an important part in senile atrophy, and the other torpid conditions of the
aged.

VI.

TISSUES IN GENERAL.
Origin, Definition, and Dr'^ision of Tissues.

ORIGIN. All complex org-anisms, the higher developed ani-
mals, originate from an ovum of the female impregnated by
the admixture of spermatozoids of the male. The ovum,
inclosed l>y a hyaline layer (zona pellucida of Yon Baer), is
composed of li\'ing matter in reticular arrangement (the germ of
Remak), which contains a nucleus-like body, the vesicula germ-
inativa, with a varying numl)er of coarser gTanules, the nucleoli,
the macula? germinativae. In mammals and some amphibia,
the germ, in foto, is transformed into the animal, whereas in the
eggs of birds, scaly amphibia, and osseous fishes, a portion of the
germ is changed to yolk, which serves as a pabulum.

After the spermatozoids have entered the germ — viz. : after
fructification has taken place — its living matter increases rapidly,
the vesicula germinativa disappears, and the germ, by a process
of di^-ision, splits at first into tAvo portions, separated fi"om each
other by a light narrow rim, but connected by extremely delicate
filaments, which traverse the light rim. Each half of the germ
spUts into a number of lumps, which, in the same manner as the
fii-st half, remain connected ; thus the segmentation of the ovimi
results in the formation of numerous corpuscles, which by col-
lecting in a flat layer represent the germinal disk of Pander, in

112 TISSUES IN GENERAL.

the germ of the impregnated egg of the chieken. The segmenta-
tion was first observed by Prevost and Dumas (1824) in the ovum
of frog ; by Coste (1848) in the ovum of fowls ; and by Bischoff
(1842) in the ovum of manmials. According to this last-named
observer, the subdivision into smaller elements in the rabbit's
germ does not go on uniformly throughout its whole extent,
inasmuch as in the germ a cavity is formed, around which the
elements of segmentation accumulate, in order to build up the
germ-membrane proper, with a slightly thickened spot, the
germ-hill of Von Baer.

The first differentiation of the germ-disk, or the germ-
membrane, consists iu the formation of layers, of which at first
two, shortly afterward three, are recognizable. The formation
of such layers became known first thi'ough the researches of
Caspar Friedrich Wolff' (1768), who claimed that the whole
S3^stem of the intestines is developed from simple laminae.
Pander, in 1817, perfected the theories of Wolff; he knew that
after hatching had continued for twenty-four hours, three easily
separable layers coidd be found in the germ-membrane. Von
Baer, in 1822, des(;ribed four layers, of which the two upper he
termed the animal, the two lower ones the vegetative. Remak,
in 1855, maintained that the germ-membrane of the impregnated
but luihatched Qg^ consists of two layers, and iipon hatching
the lower is again split into two layers, the lower of which
lines the one above it like an epithelial cover. Having ascer-
tained the individuality of each of these three layers, he
endeavored to find out their relation to the developing organs ;
he called the upper layer the horny or sensorial ; the middle
layer the motorial and germinative ; the under layer intestinal
and glandular. According to S. Strieker's researches (1860-
1870), the original under layer of Remak consists — at least above
the germ-cavity, and before the middle layer has made its appeai'-
ance — of only a single stratum of flattened cells, and the
formation of the middle layer is due to the immigration between
the two layers of new cells. He termed the Tipper layer of
Remak the combined horny and nervous layer, as he found that
in batrachia the horny layer is quite distinct fi'om the nervous
layer, the former being iiniformly thin ; the latter, on the con-
trary, thickened even in the earliest stages in that part where
later the brain is formed. He is unable to confii*m, despite of
Remak's positive assertions, that nervous elements are also
developed from the middle layer.

TISSUES /\ (iF.XF.HM.. \V.\

Strii'kor (" Mamiiil of Ilistolojiy," Anu'ricaii edition, 1 S7'_'), in Hiioakiiif? of
the tk'Vt'lopnu'nt of tiic fowl's giTin, says: " Tlu- fells of the vinder layer
change their form and arningenient during the tirst hours of incultation.
They beeoine flattened, and, when seen in transverse section, appear spindle-
shaped. Henee, after ineul»ation has gone on for a few hours, we can ascer-
tain, beyond even the shadow of a doubt, that there are two and only two
layers. . . . The under layer, immediately after its separation from the
subdivided germ, consisted in some places of a single thickness of cells,
while in other places, in a transverse section, small heaps of cells could be
recognized projecting from the layer. . . . Peremeschko, however, has
made the communication that the largo granular cells lying on the bottom of
the germ-cavity increase very consi<lerably in numbers during the first hours of
incubation. Now, since with this increase in numbers there is not at the same
time a corresponding diminution in size, it is very natural to suppose that the
cells which project from the under germ-layer fall to the bottom of the cavity.
This supposition appears all the more probable when we recall the fact that
some of the elements of segmentation which are situated in the lower portion
of the germ, remain lying at the bottom of the cavity at the time when the
germ, in the production of this very ca\ity, separates itself fi'om the subjacent
parts. . . . We are led to conjecture that the process is one of trans-
location ; that the granular bodies, which before lay at the bottom of the
cavity, liave found their way to the space between the two first germ-layers."
Strieker, based upon Oellacher's researches, says that similar relations are
also found in the trout's germ.

At present, investigators agree that the body of vertebrates is
at first a flat sheet, consisting of three main layers, for the desig-
nation of which the following names have been proposed : Exo-
derma, Mesoderma, and Entoderma, or, preferably, ppibJast, the
upper layer ; mesohlasf, the middle layer; and Ju/pohJasf, the under
layer. Of these, the epi blast and hypoblast are very thin, composed
of but one layer of plastids, whereas the mesoblast is a bulky
heap of plastids, all of which are interconnected and represent the
main mass of the future organism. As the originally flat sheet
of the germ becomes curved downward, so that the two lateral
halves are bent toward the median line, where they grow to-
gether, cavities are formed in the interior of the germ, which are
lined by the under layer and its derivatives. The horny layer
furnishes the external covering of the body and the lining of the
external glands, while the under layer provides the lining of the
intestinal ca\'ity and its glandular organs. Linings of this descrip-
tion are called "■ epithelia," and it follows that the epiblast and
hv'poblast give rise to all epithelia, viz. : the epiblast to those of
the skin and its epithelial formations (including the crystalline
lens) ; the h\^oblast to those of the intestines and their glandu-
lar elongations and accumulations. The main Ijidk of the body
8

114 TISSUES IN GENERAL.

is a product of the mesoblast ; from it proceed the tissues termed
connective tissue, which ah)ne contains blood and lymph-vessels,
muscles, and nerves, the latter arising- from the uppermost portions
of the mesoblast.

DefdsITION. In comparing the earliest formations of the germ
with a single plastid formerly called a " uni-cellular organism"
or a " protoplasmic body," such as the amoeT)a, valual)le hints
may be obtained as to the significance of the three germinal
layers. The amoeba is covered by an extremely thin layer of
living matter. If the amoeba be flattened out and bent, its cover
will represent the upper and under thin layer of the germ, which
exclusively serves as an investing layer of both the outer surface
and all ca\4ties of the body, being directly or indirectly con-
nected ^\'ith the outer world. The main bulk of the amoeba is
living matter in reticular arrangement, with thickened points of
intersection of the threads of the net-work; this matter, retaining
in the mesoblast and its derivations its reticular shape, furnishes
in higher organisms the tissues, as a result of a sort of division
of labor. The nature of the tissues is determined, fil'st, by the
manner in which the living matter is distributed, and, secondly,
by the chemical changes of the fluid t-outained in the meshes of
the reticulum.

Tissues are complex formations of livdng matter in a net-work
arrangement. The meshes of the net-work contain a Hquid which
allows the living matter to exhibit contractility in a high degree,
as in muscles and nerves, or the net-work contains a more or less
solidified basis-substance, which limits its contractility, as in the
connective tissue. The latter, on account of the presence of this
basis-substance, mainly serves as a support for the more active
tissues (muscles and nerves), and as a carrier of liquids in closed
spaces.

Dn^isiox. According to this \aew there are but four element-
ary tissues in the animal body. All these are interconnected
and built upon one and the same plan.

1. Connective tissue. In this the reticulum of living matter con-
tains in its meshes a more or less solid, nitrogenous (glue-yield-
ing) basis-substance ; while points of intersection rich in li\'ing
matter, susj)ended in a liquid, represent the C(mnective tissue
corpuscles. Of all tissues only the connective tissue carries in
closed vessels the liquids which serve for nutrition, such as blood
and lymph. Aside from this, and acting as support for other
tissues, its physiological acti\'ity is relatively small.

TTssrKs Tx (ii-:xi:h'Ar. llf)

2. Muscle tissue. The ivticulum of liviiifi; matter at its ])()iiit.s of
intiTsoction consists of moiv or less reti;ularly distiiliuted larj^e
l)risinatie, (n'lindrieal, or granular thickeuin^s (sanguis eleiuents),
eonneeted Uy thin tilainents, while the meshes eoiitaiu a li(iuid
which admits of [)owei-fid contractions of the livin<^' matter in hirj^e
territories. This tissue is the motor apparatus proper. It is
accompanied by and attached to connective tissue, carrying
the vessels.

3. Kerre tissue. Here the living matter is arranged in the
shape of either a very delicate reticulum, with very small points of
intersection (ganglionic corpuscles, gray matter), or delicate solid
cords (axis-cylinders), while the meshes contain a liquid which
allows the li\-ing matter in limited territories to contract rapidly.
This tissue serves as an apparatus of sense-impression, intellect,
and sensory and motor conduction. It is largely accompanied
by and mixed with connective tissue, carr^dng l)lood- vessels.

4. Epithelial tissue. The reticulum of living matter is very
deUcate, and arranged in flat layers, which at certain regidar in-
tervals contain a horny cement sul)stance. The function of epi-
thelial tissue is to cover the surface and the cavities of the body ; it
alone serves as apparatus of secretion, and for the formation of
the essential parts of reproduction — spermatozoids and ovum.

The Relation of Living Matter to the Interstitial
Substance.

This article is translated from a publication in German made
in 1873,* with some unimportant statements omitted.

In my studies of bone and cartilage, t I have demonstrated
that the cartilage-corpuscles send numerous offshoots into the
basis-substance termed " hyaline," and that these offshoots freely
anastomose and connect the "cells" with one another. The
material was furnished by fresh living hyaline cartilage, silver-
tinction, gold-tinction, normal calcification of cartilage, and
inflammatory calcification after simultaueoiisly wounding car-
tilage and bone.

The deposition of lime-salts in hyaline cartilage, in conse-

* " Uutersuchiuigen iiber das Protoplasma. II. Das Verhaltniss zwischeu
Protoplasma und Grundsiibstanz im Thierkorper." Sitzuugsber. der Akademie
d. Wissensch. in Wieu. Mai, 1873.

t " Studien am Kiiochen und Knorpel." Med. Jahrbiicher, 1872.

116 TISSUES IN GENERAL.

qiience of inflammation, especially served for l^ringing to view a
delicate reticulum in the l)asis-su})stance, as su(^li a deposition
took place in the chondrogenous substance, while the protoplas-
mic bodies and their offshoots remained unchang-ed. This reticu-
lum corresponded with the light (negative) figures obtained by
treatment with nitrate of silver and with the violet (positive)
figures after gold-tine tion.

I wish to add a few more observations concerning the life and
the structure of cartilage-corpuscles.

If we examine a thin section from the condyle of femiir of a
middle-sized rabl)it, in a one-half per cent, solution of chloride of
sodium, or a little serum of blood, with high amplifications, we will
see in many cartilage-corpuscles a structure identical with that I
have described in colorless l^lood-eorpuscles of man. The nucleus,
if visible, appears either homogeneous or constructed of a dense
reticulmn of a shining substance, — the living matter, — and in-
closed by a continuous layer of the same substance. The nucleus
sends delicate conical filaments into the reticulum of the cor-
puscle, and the points of intersection of this reticulum are thick-
enings, granules, or lumps of living matter. In the narrow
light rim between the protoplasm and the basis-substance we
also see delicate spokes emanating from the cartilage-corpuscles,
which are lost to sight in the finely granular Ijut in some places
distinctly reticular basis-substance.

If we heat a fresh specimen to 30-35 degrees C. (86-91 degrees
F.), we can observe in cartilage-corpuscles having a reticular
structure a continuous though very slow change in the configu-
ration of the living matter. Points of intersection flow together
into homogeneous lumps ; the latter again are differentiated into
a reticulum, and such change continues vmtil rest of the living
matter occurs — these changes in the reticulum not noticeably
altering, however, the general shape of the corpuscle.

A direct proof is thus obtained that cartilage-corpuscles are
alive, which was made probable by R. Heidenhaiu and A. RoUett
by observations of cartilage-corpuscles of the frog and newt on
the application of induced electricity.

A one-half per cent, solution of chloride of gold is a suitable
re-agent for plainly bringing to view the structure of cartilage-
corpuscles,* and for this purpose a slight tinction is sufficient.
(See Fig. 32.)

* Method of J. Cohiiheim. " Ueber die Endigung der seusiblen Nerven
in der Hornhaut." Virehow's Archiv, 38. Bd. 1867.

TISSUES IN (iKSEUAL. 117

T(» these ohsei-vations in ('artila«;e I add a series of rescai-clifs
in dirt'ei'eiit other tissues of the Ixxly.

Mfdnlhiri/ fissuf. Tlie medulla between the trabecular of a
shaft-bone of a newly hoi-n ])U]) consists of lumps of protoplasm,
whieh are iiHl)t'dded in a homogeneous V)asis-substanee. These
lumps vary «i-reatly in their aspect. However the cor{)uscle nuiy
look, invariably spokes enuiiuite from it which pierce the sur-
roundin<i- li«rht zone radiatinji:ly, and are visible with high ampli-
fication only. Where the lumps are near each other, the sjxikes
directly connect them; if, on the contrary, the lumps are
separated from each other by broad layers of basis-substance, the
spokes of a lump enter the latter, and in most instances disap-
pear. (See Fig. 33.)

The eleinents of the medulla termed "osteoblasts" by Gegen-
])aur* exhiliit the same features both in the medullary spaces of

■7^-77

Fig. .'}!'. — Cartilage Corpuscles from the Condyle op Femur of a
New-eorx Pup. [Published in 1873.]

Clironiic acid specimen slislitly stained with chloride of gold. C, coi-puscle with one
compact, vaciioled nucleus : C'^, with a pale heap of granules above it ; d, with two nuclei and
several heaps of gran iili's. Magnified 1000 dianietcis.

newly born pups, close to the bony trabecular, and in the vascular
canals of shaft-bones of older animals.

Where the elements lie close to the bone- wall, they are sepa-
rated from the latter by a light rim, and the filaments, springing

* Jenaische Zeitsehr. f. Mediz. tniil Naturwissensch. I. Band. 1864, This
observer knew already delicate offshoots, like cilia, emanating from osteo-
blasts.

118

TISSUES IN GENERAL.

from the medullary corpuscles, pass through the rim into the basis-
substance. Where the medullary corpuscles are near the border
of a vessel, their offshoots truA-erse the light, perivascular rim
and inosculate \\-ith tlie wall of the blood-vessel. *

Upon slight gold tinction of chromic acid specimens previously
exposed to water, the spokes exhibit a distinct violet color. The
longer the solution of gold acts, the more distinct will be a differ-
entiation in the basis-substance. The protoplasmic lumps at last
appear as dark violet, densely reticular corpuscles with numerous

Fig. 33. — Medullary Tissue from a Longitudinal Section of the
Femur of a New-born Pup. Chromic Acid Specimen. [Published
IN 1873.]

B, bonc-rori)uscIe ; P', vacnoled plsi.stid ; P2, reticular nucleated ]>lastiil ; M, apparently stnict-
nrelesH l)asis-8iib.stance : ^', capillary blood-vessel. JIa;rnitie<l S()(l diaiueters.

delicate radiating spokes, which blend witli a partly coarse, partly
delicate, reticulum. (See Fig. 34.)

* Coiifr. "Ueber die Rik-k- iiiiil Nculiililung von Blutgefassen im Knoehen
iind Kiiorpel." Med. Jahrbiieher, 1S73.

Tissi'J'JS jx (ii:.\i:i!.\L.

119

Tlic l)iisis-sul)stanco is travorscd bv si rt'ticuliini wliicli lias for
points of intersection of its threads coarser and finer fi:rannles.
By tracinji; the action of the ^ohl solntion, we can satisfy ourselves
that the (h'nsest reticulum with the smallest mesh-spaces belonj^s
to the yellowish, shininj; medullary elements, and the larger
violet lumps are either homojivneous nuclei or nucleoli. The
most delicate reticulum with smallest {i:ranules as points of inter-
section, aiul the largest mesh-spaces, correspcmds to those places

'■^^"^ '

Fig. 34. — Medullary Tissue from a Longitudinal Section of the
Femur of a New-born Pup. The Bone-tissue Decalcified by
Chromic Acid, and the Specimen Intensely Stained with a Solu-
tion of Chloride of Gold. [Published in 1873.]

BR, bone-corpuscles ; P, partly vacuolert, partlj- reticular plastids : M, the basis-substance
exhibiting a reticular structure. Magnitied 800 diameters.

of the medullar^' tissue which, in the unstained condition of the
specimen, appeared as an apparently homogeneous and structure-
less basis-substance.

120 TISSUES IN GENERAL.

Tissue of the VmhiUcal Cord. Longitudinal sections of the
human umbilical cord, hardened in a chromic acid solution,
exhilnt, as is well known, a striated or fibrous structure. The
fibers are densest at the periphery of the cord and around the
blood-vessels, and these layers are interconnected by a relatively
coarse reticulum of fibers, the meshes of which contain a homo-
geneous substance. In the fibrous layers we meet with large,
nucleated, freely branching protoplasmic masses, also with
smaller, spintlle-shaped bodies, and with very smaU protoplasmic
cords and lumps, devoid of nuclei. In the mesh-spaces, traversed
by a few fibers which the cutting has partly torn, we encounter
apparently isolated globular corpuscles, havdng one or several
nuclei, but no offshoots.* The amount of h\'ing matter in the
protoplasmic bodies is variable. We find compact lumps char-
acterized by a nearly homogeneous structure, considerable luster,
and yellow color; furthermore, coarsely and finely granular
corpuscles, with either homogeneous, shining, or finely granular
pale nuclei, some containing nucleoli; lastly, very pale, deli-
cately gi-anular bodies destitute of both nuclei and a marked
boundary line toward the basis-substance. The periphery of all
these corpuscles, while they are in connection Avith the tissue,
looks more or less scalloped or thorny, and the same is the case
with their nuclei.

Upon rubbing a fresh umbilical cord vdXh a stick of nitrate of
silver, and exposing the specimen, kept in water, to the daylight,
it will soon become brown, t

Longitudinal sections of an umbilical cord colored in this
way exhibit, even with lower amplifications, numerous many-
shaped light and colorless fields in the brown basis-.substance.
High amplifications demonstrate that the light fields in different
directions send branches into the basis-substance, | and that from

* For reference: Kud. Virchow's " Cellularpathologie," 4 Aufl., 1S71.
Weisman. ■ ' Zeitschi-ift fiir rat. Mediz." 3 Eeihe, Bd. xi., 1S61. K. Koster,
•'Ueber die feinere Struetur der menschl. Nabelschnur," Wiirzbm-g, 1868.
Koster found the globular corpuscles in the mesh-spaces, and the spindle-
shaped cells near the spaces without fibrils, to be amoeboid.

t Method of F. von Recklinghausen (" Die Lj-mphgefiisse und ihre Bezie-
hung zum Bindegewebe." BerUu, 1862). Specimens containing black,
granular precipitations I consider as useless. The features described can bo
observed only when the basis-substance is stained light or dark brown, and
the fields con-esponding to the protoplasmic bodies are colorless.

t Koster (J. c), by means of the silver tinction, brought to ^-iew the larger
light fields onlv.

TISSIKS IX (iKXKRAL.

121

all those liijlit fields mikI their offshoots a delicate varicose
reticulum starts, wiiich traverses the whole of the lirown basis-
substance. (See Fig. 35.)

Sli^rht (Told tinetion shows that the violet nucleated l>odies
and their coarser otlslioots correspond, both in size and shape,
with the lar<;e lif^ht tields lu-ou^ht to view l)y nitrate of silver.
In specinu'us deeply st<iined with chloride of gold, we observe
that, from each dark v-iolet corpuscle and its offshoots, numerous

Fig. 35.— Longitudinal Section from the Cortical Portion of the
Human Umbilical Cord, Stained with Nitrate of Silver. [Pub-
lished IN 1873.]

s anil B. largtr and smaller light siiates traversing the biown basis-suhstant e, whirli every-
where is pierced by a delieate light retictUinn. Miagnitteil 800 diameters.

very delicate dark violet filaments proseed, penetrating a vari-
cose gi-anular net- work. The latter traverses the basis-substance

122

TISSUES IX GENEBAL.

in a dii-ectiou mainly vertical to that of the fibers. Even a single
fiber can be seen to be composed of alternating light \-iolet and
dark violet portions. (See Fig. 36.)

Fig. 36. — LoxGiTrniXAL Section from the Cortical Portion of the
Human Umbilical Cord, Intensely Stained with Chloride of
Gold. [Published in 1873.]

P, the i)lastiils (protoplasmic bodies) with nuclei; S, siualler spindle-shaped plastids,
connposinj; the liasis-suhstance ; F, torn tibrilla, with an alternating light and dark stain.
MagniJied 800 diameters.

Numerous torn fibers originate fi-om bipolar nucleated lumps,
and each fiber appears to be pierced by a dark violet reticulum.

Tissue of Tendon. Similar features are found in the tendon.
On rubbing the silver stick over the tendon Achillis of a freshly
killed dog several years old, or of a gi'own rabbit, exposed to
daylight, the brown tinction will appear after a while.

With lower powers we recognize in longitudinal sections of a
tendon-bundle numerous narrow, spindle-shaped light fields,

TfSSf'h'.s' I.\ (Ih'Xhh'AL.

12.']

tlie (lark-brown Ixn-dcr of wliicli i;^ ^■t'l•ti('ally pci'foi-atcd liy li^'lit
lines, while tlif surrounding- l)asis-sul)stanee looks uniforndy
brown and lionio<i;oneous.* Toward the perij)lii ry, the lijjht
fields are lai-jicr and often lonj^'itudinally forked; in the peri-
tendinous tissue they are very nunu'rous, numy-shuped, and
separated by nai'i-ow, lirown fields, or streaks of the basis-
substane*'.

Hi<ih ainplifieation shows that from the periphery of the light
fields and their offshoots delicate light lines arise in a vertical
direction, which l)lend with a varicose reticulum throughout the
basis-substance, and thus connect each larger uncolored field
with its neighbors. (See Fig. 37.)

Fig. 37. — Longitudinal Section op the Tendo Achillis of a Grown
Dog, Stained with Nitrate of Silver, [Published in IS 73.]

.S"', liglit liraucliiiiff fielil, with a i>ale, dini imclcus: ,S'2, offshoot of a li^lit lield in the
iniilillc of basis-siibstauce ; .S'^, bifurcatioii iiichjsiug a narrow pes of hasis..siil).staiic«- ; B, dark
brown basis-sub.stauce pierced by a mostly rectangular lijrlit reticulum. Magnified 800
diameters.

Slight gold tinction reveals the identity of the pale violet
bodies with the protoplasmic corpuscles seen in chromic acid
specimens ; they are identical, as regards their shape, also, with
the negative fields ol)tained l)y silver tincti(m.t After intense
gold-stain, the striated basis-substance looks pale violet. There

* V. Reekliughausen (I. e.) also has obsei-ved anastomosing light fields in
the silver-stained tendon.

t In this respect I concur with Giulio Bizzozero (Rendiconti del R. Isti-
tuto lomb. delle seienze, 18G9) and Paul Giiterbock (Centralblatt fiir die
Med. Wissensch., 1870).

124

TISSUES IN GENERAL.

are dark Wolet, in part branchinii' bodies iu it, which send dark
xdolet filaments into the basis-substau(;e, mainly at ri^ht angles.
Where the tendinous tissue is torn into bundles or single fibers,
we easily recognize the dark violet reticulum, and in each single
fiber the pale \'iolet basis-substance contains, at in-egular
intervals, dark violet granules. On the border of some fibrous
bundles small scallops protrude. The cross-section of a small
bundle shows two kinds of formations : one granular, partly
branching, dark violet ; the other, homogeneous, colorless, or
pale \dolet. (See Fig. 38.)

Tissue of the Periosteum. In chromic acid specimens of the
periosteum of shaft-T)ones of gi-own dogs and cats, the light

Fig. 38. — Loxgitcdinal Section of the Texdo Achillis of a Grown
Dog, Deeply Stained with Chloride of Gold. [Published in
1873.]

P, the brandling tcii»\on-cori>H8i'les, with liglit nuclei: B, buniUe with (lir«tinrt rectanK"lar
(lark violet filaments; F, single dotted tibiilUe ; TS, transverse section of a bnnille. Magnified
800 diameters.

basis-substance, partly striated, is composed either of rhomboidal
plates or of broad ri})l)ons, which may exhibit a mosaic of
rhombs. These formations are intermixed and interlaced in a
vertical or oblique direction.

The variety of basis-sul)stance consisting of broad ribbons is
met with, as a rule, on the surface of the bone.* while the other

* The protoplasmic layer between periosteum and bone, which Th. BiUroth
(Ai-chiv fiir Klinische Chirurgie, Bd. y\.) has termed "cambium," exists in
juvenile animals only.

'jissiKs i\ a km: UAL.

125

varietios ])rovail at the periphery of the periosteum, bU'iidiuf;
with iiei<>lil)()riiii»" tissues. Tlie ribbons are separated from ea<*h
other in a hniiiitudiiial direction by straitj^ht so-eaUed ehistii;
fibers, wiiieh renck'r eaeh ribbon rhomb-shaped. At the corners of
the rhoml), the elastic fibers anastomose with eaeh other in acute
anjjh's. A In-oad ri1)l)ou is not infrequently subdivided by elastic
fibers into smaller rhombs.

MT

ML

Fig. 30. — Longitudinal Section op the Periosteum of the Femur of
A Grown Dog, Stained with Nitrate op Silver. [Published in
1873.]

C, liglit si)afe.s corrcspoiKliuft to tin- plastids, all of wliicli are interconnectetl ; MT. smooth
nmscU' fibers of an artt'ry in trausviTse section; ML, tlie same iu loiigitiulinal section; K,
emlothelium. Masniitied 800 diameters.

The protoplasmic bodies are spindle-shaped in the striated,
rhomboidal in the rhomb-shaped, and oblong in the ribboned
basis-substance. In the interstices between the lavers similar

120 TISSUES IN GENERAL.

corpuscles are imbedded. Properties common to all of these
corpuscles are : tliey lie in cavities of the basis-suhstance, their
l)eri]>liery is scalloped, and they are possessed mostly of one
nucleus. The nucleus and nucleoli look exactly like those of
colorless blood-corpuscles.

In the basis-substance, stained lu-own })y nitrate of silver,
lig-ht fields of varjdng- shape appear, which behave Uke those of
the umbilical cord and the tendon. Here, too, the basis-substance
is traversed by branching lines, which interconnect the large Kght
fields. (See Fig. 39.)

Slight gold tinction of the periosteum brings to view deli-
cate radiating scallops at the periphery of the corpuscles, and

delicate vertical filaments in the
\ - ,., interstices between the rhombs.

The shining elastic ledges are
transversely striated, being
pierced by violet filaments. Deep
gold-stain shows a dark ^dolet
3^ reticulum throughout the basis-

H^ ' - . ^ sul)stance, iust as in other va-

^ rieties of connective tissue.

^*^ The perkJiondrimx in all es-

'V sentials is identical in its struct-

"I ure with the periosteum. Where

t fihroHS rarfilagc blends with peri-

%^ -, chondrium, as on the lateral sur-

1!^-=*^ > H* faces of the condyles of femurs

'"" ''' ^'''^" of younger animals, the gold

Fig. 40.— Bone-corpuscle from a tinction evidences a dense re-

PuRPosELY Wounded Scapula of ^i^^^^,^ of offshoots of the cor-

Cat — TmRD Day of Inplamma- , „ „, ^.,

TioN. Chromic Acid Specimen. P^scles of fibrous cartilage.

[Published IN 1872.] Tissue of hone. The basis-sub-

f, the Loaiiy iiomogeneous piastid, with stauccof juveuilc boucis striated,

numerous lanniyiug offshoots. Masnifie.! 800 that of older l)one lamcllated.

uiameteis.

The lamell* are plates separated
from each other by a non-calcified basis-substance, and each
lamella is composed of flat, ol)long lenticular masses, which are
curved according to the lamella and contain one central bone-
corpuscle.

In the earliest stages of inflammation of bone, the protoplasma
swells so that, without any re-agent, numerous ofl'shoots of the
bone-corpuscles become visible, which freely anastomose and pro-

yv.s'.sr/'.'.v IX CKXKUAL. 127

duce a drlicatt' rfticulmii tlii-(»iiL''li<»ul the liasis-substance. (See
Fi-.40.)

lihxul-vcssch. Fi<;. ;]1) represents an artery from the silver-
stained periosteum ot a g^rown do^, in wliich we reeojrnize
that the hrown basis-suhstanee of the adventitial eouneetive
tissue, the cenient-sul)stance between the spindle-shaped muscle
fibers, and the eement-sul^stanee between the endothelia, are all
traversed by lifjht lines, which intereonneet the light fields cor-
responding to these formations.

Gold-stains bring to view, in the interstices between the single
elements, conical filaments which connect all. The walls of capil-
laries of the compact snl)stance of shaft-bones are, by means of
filaments, in dii-ect connection with the neighboring corpuscles,
both of medulla and bone. These filaments penetrate the space
around the hollow ])rot()])lasm of the vessel, the '' perivascular
lymph-space" of autliors.

Miisch-fisuHP. In continuous layers of smooth muscle, both in
the fi'esh condition and after the gold stain, we see that from
each spindle arise numerous spokes, which, after having pierced
the surrounding cement-substance, inosculate with the neighbor-
ing spindles. In such spindles, especiall}' from the muscular
wall of the blood-vessels of the umbilical cord, there is an accu-
midation of li\4ng matter which renders the corpuscle nearly
homogeneous and highly refractive. In very shining spindles
there are no nuclei. Wherever nuclei are seen, they are by
means of conical spokes connected with the reticulum of li\'ing
matter of the corpuscle.

The examination of Jiring striated muscle fi'om the thigh of the
water-beetle (Hydi-ophilus) or craw-fish (Astacus) shows that
the distri])ution of the contractile or '* main " substance varies
greatly. In opposition to the conceptions of W. Krause,* V.
Hensen.t Th. W. EngeLmann,t and others, I adopt the view of E.
Briicke,§ \iz., ''that the sarcous elements do not exist as solid
and unchangeable masses in the li^dng muscle, ])ut are groups of
molecides an-anged in colimms of a varying configuration at the

* "Ueber den Bau der quergestreiften Muskelfaser." Zeitschrift f. rat.
Medizin, 1868.

t " Ueber ein neues Structurverhaltniss der quergestreiften Muskelfaser."
Arbeiten des Kieler physiolog. Institutes, 1868.

t * ' Mikroskopische Untersuehungen tiber die quergestreifte Muskelsub-
stanz." Pfliiger's Archiv, 1873.

6 ' • Untersuehungen iiber den Bau der Muskelf asern mit Hiilf e des polar.
Lichtes." Denkschrifteu d. Wiener Akademie d. Wissensch. , Bd. x^^

128

TISSUES IN GENERAL.

m

.\'-

-t^U"

iiiomont of death." I am unable to see in the li\'ing, striated
muscle anything else than in the li\ang protoplasma in general —
namely, granules and heaps of granules of li%-ing matter, the
sareous elements, and between these a non-contractile interstitial
substance.

Whatever form the distribution of the contractile substance
may give rise to, we can prove that every granule and every
sareous element is in all directions connected with its neighbors
by means of delicate gray filaments piercing the interstitial sub-
stance in vertical and transverse directions. From each so-caUed

" muscle-nucleus," and in case
the nucleus is surrounded
by protoplasm, from the lat-
ter, emanate delicate conical
threads, which, after ha^^ng
penetrated the narrow light
rim, blend with the neigh-
boring sareous elements.
(See Fig. 41.)

In gold-stained specimens
these features are far more
striking than in fresh muscle,
as the chloride of gold, acting
for a sufficient length of time,
Q. — viz., twenty to forty min-
utes,— stains the contractile
substance of muscle \aolet.

Sfrucfure-eJeinenfs of the
Xervous System. Thin sec-
tions from the cortex or the
main ganglia of a gi'own, re-
cently killed rabbit are the best specimens for examination with
high powers of the microscope. The section may be transferred
to the slide without or with the addition of a preser\'ing fluid ;
in the latter case, a very dilute solution of l)ichromate of potash
is preferable, because, as proved by A. Rollett. this does not alter
the structure of protoplasm. Layers of protoplasm, with numer-
ous formations like nuclei, ganglion-corpuscles of varying shape,
and non-medullated* nerve-fibers of different size are seen. The
li^-ing matter in the formations termed nucleoli, being compactly
accumulated, is homogeneous, and has a yellowish luster ; while

* The original reads by mistake "mediillated,"

Fig. 41. — Portion of the Fresh Thigh-
muscle OF Hydrophilus Piceus.
[Published ix IS 73.]

X, nucleus : G, grannies in the longitudinal ilirec-
tion of the nucleus. Magnified 800 diameters.

1 1 ss I ■ j-:s 1 x a k.\ i:ii. i l

Vl\)

iu the |)r()t()])lasm!i of all structure-elements of the iiei-vous
system it is disti-ihuted in thin layers as "granules and lumps,
and is of an opaciue f^ray color. All jiranules and lumps of the
livinjr nuittor are interconnected 1)V delicate radiating spokes.
(See Fi^rs. 42 and 43.)

In the irauirlion-corpuscles. especially in their nuclei, the
spokes have been observed )>y a hirii;e number of investigators,*
who interpreted these spokes as belonging exclusively to gan-
glion-corj)uscles, or as ])rod-
iiets of coagulation. I am
unable to see iu these forma-
tions a structure different
from that of cartilage-corpus-
cles or that of living proto-

.V

#

Fig. 42. — Section from the Cor-
tex OF THE BrAIX of A RECENTLY

Killed Grown Rabbit ; Kept in
A One-half per cent. Solution
of Chloride of Sodium. [Pub-
lished IN 1873.]

/', the graj-ish rftictilum of liv-ing matter,
vritli mimerous nuclei, X. Maguified 800
diameter.s.

Fig. 43. — Specimen from the Cor-
pora Quadrigemina of a Recently
Killed Grown Rabbit ; Kept in
A Dilute Solution of Bichro-
mate OF Potash. [Published in
1873.]

lu tlie gTa3-lsli reticulum of living matter
there are nuclei, X; gangliou-conniscles, (? ;
witli axis-C3limUr offshoots, A. Some axis-
cjiinders with varicosities, V. Magnified 800
diameters.

plasm in general ; true, iu the

ganglion-corpuscles the struct-

ui-e is very promineut. Such spokes are in some cases also dis

tiuctly seen to project from the periphery of the ganglionic cor

* The literature is found in Jul. Ai-nold, " Ein Beitrag zu der feinereu
Striiettir der Ganglienzellen." Virchow's Arcliiv, 41 Bd. 1867.

9

130

TISSUES IN GENERAL.

iMi

FF-

MF—

puscles, as well as to proceed from the inediillated and non-
mediillated nerve-fibers, and to traverse the light rim around all
these formations.

Th(^ same strnctiire is visible in the ganglionic corpuscles of
the sympathicus nerve of the rabbit. Here the spokes directly con-
nect corpuscles lying
near each other, and
penetrate also the inter-
•"EL stiee between the cor-
puscles and the cap-
sule, being lost to sight
in the latter.

The pale protoplas-
ma of the nervous sys-
tem, as is well known,
is easily stained violet
with solutions of clilo-
ride of gold, and such
solutions, cautiously ap-
plied, furnish a valua-
ble means more plainly
to bring to view the
features of the struct-
iu*e of nerve-elements
described.

Ep ifhelia I Tissue.
The forms of the so-
called '' prickle and
ridge cells" are known in many epithelia; they hav^e been first
described by Max Schultze * as normal occurrences in the pave-
ment ejnthelia of the skin, the lips, the mucosa of the oral
cavity, the tongue, and the conjunctiva of the ej-elids. The
thorns are nothing but offshoots of an epithelial corpuscle, which
traverse the light rim of cement-substance to join all the neigh-
boring corpuscles. The thorns are conical. They are either so
arranged that from one element alternately the liroad base of a
cone projects, and the next thorn is inserted with its point into
the element ; or, as Bizzozero has demonstrated, the points of the
thorns projecting from two neighboring corpuscles meet in the
rim of the cement-sul)stance.

Owing to these offshoots, the cement-substance, if cautiously
stained brown by nitrate of silver, is pierced by transverse light
* Centralblatt fiir die Mediz. Wissenschaften, 1864.

Fig. 44. — Surface-epithelium of a Villus of
THE Small Intestine of a Grown Dog.
Slight Gold Stain. [Published in 1873.]

EL, coUiuiiiar epithelia iu side view ; JEF, columnar epi-
thelia in top view ; ML, epith(>liiini traiiMformed to mucus,
in side view ; MF, same in top view ; .S', tlie striated seam
of tlie epitlielia. Magnified 800 diameters.

TISSUES IN GENERAL.

i:n

liiifs: wlu'ivas ^old tinction colors tlio projections intorconiicct-
iiii>- the \iolct epithelial Ixxlies also violet, leaving the cenient-
sul)staiice nnstained.

I liave not seen elements in e])ithelia other than so-called
•• priekle-eells " interconnected with one another. (See Figs. 44
and 4"),)

; From my descriptions it follows that all elements of the
tissnes of the animal body are '' prickle-cells," all nuclei are
" priekle-nnclei," and all nucleoli " prickle-nucleoli.''

Examining the epithelial corpuscles of glands, we are satis-
tied that the projections of one '' enchyma-celP' not only reach all
neighboring " enehyma-cells,'' but that at the periphery of the
lobule or tubule of a gland they estalilish a direct union between
the enchyma and the connective-tissue corpuscles.

The first conclusion to ^*%\!r\ 4 />\i -

be drawn from my re-
searches is that in no
tissue whatever do there
exist " cells " as isolated
individuals.

Each tissue represents,
speaking in the usual way,
a colony of cells, in which
one cell is uninterrupt-
edly united by filaments
of living matter with all,
and all with one. Each ^
" cell-colony " again is con-
nected with the neigh-
boring colonies without
interruption, so that the
whole animal body may
be considered as a sin-
gle cell-colony. In other
words :

The animal hodi/, as a
ivJiole, is one protoplasmic mass, in ivhich are imhedded a relatively
small numher of isolated protoplasmic corpuscles (migrating, color-
less, and colored blood-corpuscles), and various other non-livine/
substances (glue-yielding and mucous substances, fat, pigment-
granules, etc.).

-^

Fig. 45. — Section of the Submaxillary
Gland op a Middle-sized Rabbit.
Slight Gold Stain. [Published in
1873.]

AA, acini lined by epitlielia (temieil also "encliyina-
cells"); C, conuoftive-tissuc frame. Magnilifd 300
iliaineteis.

132

TISSUES IN GENERAL.

Just as the amoelja is a protoplasmic lump, iu which the
living matter is arranged in the form of a reticulum, whose
points of intersection are also living matter, so the body of even
a highly organized mammal is a lump, traversed by a living
reticulum, whose points of intersection are living matter in the
shape of 'protoplasmic corpuscles, hitherto termed cells.

Fig. -iLi. — Schema of the Stri'ct the Varieties of Con-

nective Tissue. [Pcblished in 1873.]

Every tissue, as the history of development teaches, is built
up by a number of protoplasmic lumps, Avhich we may consider
as the eleiiip)its of the tissue. In a completely formed tissue, the
cell and its territory (Virchow) represent the i(nif of the tissue.

TrSSFES TX (iEXKUAL. 133

which is l>v no iiu'uns an individnal, as eacli unit is in direct,
livinu; connection with all ncighl)oring nuits.

Let us bejrin with the analysis of the units in the formations
termed " c(»nne<'tive tissue." In the center of the element is the
nucleolus, annind this the nucleus, and next a protoplasmic body,
hitherto termed " cell" ; this is surrounded by a protoplasmic mass,
infiltrated with a ixlue-yielding- basis-substance, and within this
unit of the tissiu' the living nuitter is uninterruj)tedly c(jnnected.
It is accumulated in the center in the shape of a compact uurlcolus -,
next it constitutes a sometimes narrow, sometimes wide, reticu-
lum, and incloses this reticulum as a continuous layer in the
shajte of the nucleus ; then it forms a somewhat Avider reticulum,
holding protoplasmic liquid, and, as a rule again, a continuous
sheU, inclosing this reticulum in the shape of the cell; and, lastly,
is spread out in the shai)e of a relatively wide reticulum, whose
meshes are infiltrated with 1)asis-substauce, as the ccU-ttrritonj.
(See Fig. 46.)

This schema may exhil)it modifications if either the nucleus in
foto or the whole element in fofo is a compact, homogeneous mass
of living matter. Such conditions are due, as I have explained
before (see page 46), to differences of age of the protoplasm.

Each of the constituents of a unit described is separated from
the neighboring constituents by a space, as a rule, containing a
liquid, traversed not by a reticulum, but simple filaments of the
living matter. Such spaces, therefore, exist around the nucleolus,
around the nucleus, around the protoplasm, or cell, and around the
infiltrated portion of the unit, although until the preseW time
only the pericellular spaces were known. In aU these spaces a
circulation of liquids can take place, and each may be filled by
parenchymatous injection with colored substances. Such injec-
tions have been made around the nucleus (by Mac-Gillavry) ;
around the cell (by Kowalewsky and others) ; around the bor-
ders of the units of the tissue, and, lastly, around the perivascu-
lar spaces. By such foi'cible injections the connecting filaments
are torn and the protoplasmic bodies become displaced and com-
pressed. We can readily understand how^ lymph-clefts, desti-
tute of walls, could be manufactured by such parenchymatous
injection.

The schema of the units of epithelium is different. In
the center of the element is the nucleus with the nucleolus.
Both are imbedded in a protoplasmic body surrounded by the
shell of cement-substance common to all neighboring elements,

134 TISSUES IX GENERAL.

wliich contains the spokes or pi-ickles connecting the elements.
Features similar to those of epithelia may also be exhibited by
some connective-tissue corpuscles, especially those of the medul-
lary tissue (osteoblasts) and the endothelium ; the same are found
in the tissue of smooth muscle. I intend to demonstrate here-
after that the development of a unit of connective tissue is
invariably preceded by a stage which corresponds to the schema
of epithelial formation ; we are therefore not justified in making
an essential difference between the elements of connective tissue
and those of epithelium, exclusively based on tlifferences in theii*
shape.

Just as each independent protoplasmic lump, and within it
each vacuole, is bordered by a continuous layer of living matter,
so the body of a mammal, and in its interior every cavity, is
covered by a continuous layer of protoplasm.

Based upon the facts hereinbefore described, we may obtain,
as I shall later show, a clear ^dew of the development of the
tissues and of the inflammatory process. During inflammation,
especially that of certain tissues, conclusive proofs are fiu'nished
that there is in the basis-substance a large amount of li\dng
matter which is liable to become diseased.

Is Blood a Tissue ? As one of the consequences of the
modern \dews regarding individuals, it is held that blood, pus,
secretions, etc., are fluid tissues. I have demonstrated that every
animal tissue is a continuous mass of protoplasm, with zones of
ditferent structure. An " intercellular substance " exists here as
little as "cells," in the modern sense, are present. We are
justified in speaking only of basis-suhsfance.

That single lumps, as migrafiiir/ cells, discovered by Von
Recklinghausen, are, for a time, disconnected fi'om other ele-
ments and execute locomotion of theii* own, does not alter the
general rule. Migrating corpuscles are not essential constituents
of a tissue.

In the blood, isolated protoplasmic lumps, the red and colored
blood-corpuscles, float in a liquid plasma. Protoplasmic lumps
are likewise suspended in liquids such as pus, colostrum, bile,
sperm, etc. Such li(piids we have no right to call tissues.

The analogy between a living amaba and the body of a
higher animal as to its lixing blood-corpuscles is apparent
enough. In the amoeba there arise transient vacuoles, in some
of which, as I have demonsti-ated liefore (see page 22), granules

TfSSrES TX aKXKJiAT.. KJ')

of the ('ontractiU' matter may be susiK'iided ; and Ijlood-vcssels
arise from the formation of vacmdes (see pa^je 'M\), eontaining
from tlieir very oriiriu a liquid in which isolated Inmps of living
matter are snspendtd.

Keseakcues anj> Deductioxs SIXCE 1873.

I have ])ur]»()sely given an accurate translation of my
assertions in 1878, in order to show that the eell-theory and
its consequences, in the light of my investigations, had to Tdc
al)andoued. At present, after nine years' further research, I
have nothing to alter in my previous statements, and but little
to add.

Various publications, based on studies made in my laboratory
during the last seven years by unprejudiced observers, fully
corroborate the new ^dews. Not only physiological and histo-
logical research, but pathological investigation as well, ajnoU
become more fruitful. Inflammation, tul)erculosis, formation of
tumors — in short, all morbid processes — will be better under-
stood than is possible with cellular-pathological views.

L. Elsberg, in 187.1,* makes the following statements :

" Not only in the wide domain of organic physiology, but
especially also in human pathology, the cell doctrine has been
accepted so universally that it seems to me eminently proper to
bring the new \-iews to the notice of the American Medical Asso-
ciation, even at this early stage of their crystallization into a
complete doctrine. AU that I shall present to you as histological
fact has been repeatedly observed and demonstrated by C. Heitz-
mann, both at Vienna and New York ; and a number of others,
as well as I, have been enabled to confirm his observations.

" The ideas of humoral and solidistic pathologists long con-
tinued to influence medical teachings after Schwann's dis-
coveries of the elementary sti-uctm-e of tissues were generally
acknowledged as correct, and more or less consistently applied.
It was really not until Virchow promulgated his celebrated
lectures on cellular pathology, less than twenty years ago, —
lectiu'es which reached and deeply impressed the medical pro-
fession in every portion of the globe, — that the ceU-doctrine
has had undisputed sway."

* Notice of the Bioplasson Doctrine. Transactions of the American
Medical Association, 1875.

]3G TISSUES IX GEXEIiAL.

In Lecture I., delivered February 16, 1858, Virchow said: "K we con-
sider the extraordinary influence which Biehat, in his time, exercised upon the
state of medical opinion, it is indeed astonishing that such a relatively long
period should have elapsed since Schwann made his great discoveries without
the real importance of the new facts having been duly aijpreciated. This has
certainly been essentially due to the great incompleteness of our knowledge
with regard to the intimate structure of our tissues, which has continued to
exist until quite recently, and, as we are sorry to be obliged to confess, still
even now prevails with regard to many points of histologj, to such a degree
that we scarcely know in favor of what view to decide. Especial diflficulty
has been found in answering the question from what parts of the body
action really proceeds, what parts are active, what passive ; and yet it
is already quite possible to come to a definite conclusion upon this point, even
in the case of jjarts the structure of which is still disputed. The chief point
in this application of histology to pathologj- is to obtain a recognition of the
fact that the cell is really the ultimate moi-jihological element in which there
is any manifestation of life, and that we must not transfer the seat of real
action to any point beyond the cell." And further on he said: "According
to my ideas, this is the only possible starting-jjoint of all biological doctrines.
If a definite corresj)ondenee in elementary- form jjervades the whole series of
all li\-ing things, and if in this series something else which might be placed
in the stead of the cell be in vain sought for, then must every more highly
developed organism, whether vegetable or animal, necessarily, above all, be
regarded as a progressive total, made up of a larger or smaller number
of similar and dissimilar cells. Just as a tree constitutes a mass arranged
in a definite manner, in which, in every single part, in the leaves as in the
root, in the trunk as in the blossom, cells are discovered to be the ultimate
elements, so it is also with the forms of animal life. Every animal presents
itself as a sum of vital unities, every one of which manifests all the character-
istics of life. The characteristics and unity of life cannot be limited to any
one jjarticular sx>ot in a highly developed organism (for example, to the brain
of man), but are to be found only in the definite, constantly reiurring, struct-
ure which every indi\'idual element displays. Hence it follows that the
structural composition of a body of considerable size, a so-called indi\'idual,
always represents a kind of social arrangement of parts, an arrangement of a
social kind, in which a number of individual existences are mutually depend-
ent, but in such a way that every element has its own special action, and
even though it derive its stimulus to activity from other parts, yet alone
effects the actual performance of its duties. I have therefore considered it
necessary, and 1 believe you will derive benefit from the conception, to portion
out the body into cell-territories (Zellen-territorien). I say territories, because
we find in the organization of animals a peculiarity which in vegetables is
scarcely at all to be witnessed, namely, the development of large masses of
so-called intercellular substance. Whilst vegetable cells are usually in imme-
diate contact with one another by their external secreted layers, although in
such a manner that the old boundaries can still always be distinguished, we
find in animal tissues that this species of arrangement is the more rare one.
In the often very abundant mass of matter which lies between the cells
(intermediate, intercellular substance) we are seldom able to perceive at a
glance how far a given part of it belongs to one or another cell ; it presents
the aspect of a homogeneous intermediate substance. According to Schwann,

'nssij-:s i.\ <;j:xKT{\r.. vm

the intorcpUular sulistniu'i' was tlu- cvtoldastcma <h'.stiiieil forthedevolo])intM)t
of new cells. This I do not eonsidiT to be coiTet-t, but, on tlu' contrary, I
have, by means of a series of jiatholof^ical oV)servatioiis, aiTived at the concdu
sion tliat tlie intercellular substance is dependent in a certain definite manner
upon the cells, and that it is necessary to draw l)Oundaries in it also, so that
certain districts lielong to one cell, and certain others to another. You will
see how sharjdy these boundaries are defined by pathological processes, and
how direct evidence is affoi-ded that any given district of intercellular sub-
stance is ruled over by the cell which lies in the middle of it, and exercises
influence upon the neighboring parts.

" It must now be evident to you, I think, what I understand by the terri-
tories of cells. But there are simple tissues which are composed entirely
of cells, cell lying close to cell. In these there can be no difficulty with
regard to the boundaries of the individual cells, yet it is necessary that I
should call your attention to the fact that, in this ease, too, every individual
cell may run its own peculiar course, may undergo its own peculiar changes,
without the fate of the cell Ijing next to it being necessarily linked with its
own. In other tissues, on the contrary, in which we find intermediate sub-
stance, every cell, in addition to its own contents, has the supei'intendence of a
certain quantity of matter external to it, and this shares in its changes — nay,
is fi-equently affected even earlier than the interior of the cell, which is ren-
dered more secure by its situation than the external intercellular matter.

'' Finally, there is a third series of tissues, in which tlie elements are more
intimately connected with one another. A stellate cell, for example, may
anastomose ^^•ith a similar one, and in this way a reticular arrangement may
be produced similar to that which we see in capillary vessels and other analo-
gous structiu-es. In this case it might be supposed that the whole series was
ruled by something which lay, who knows how far off ; but iijion more accu-
rate investigation, it turns out that even in this chain-work of cells a certain
independence of the individual members prevails, and that this independence
evinces itself by single cells undergoing, in consequence of certain external
or internal influences, certain changes confined to their own limits, and not
necessarily participated in by the cells immediately adjoining." *

" Now, according to Heitzmami, what Virchow asserts of ' a
third series of tissues ' is really true of all tissues. Not only are
there contained no cells as isolated individuals in any tissue of
the body, Init no tissue in the body is isolated from the others.
He prefers not to use the term ' cells ' ; he speaks of ' living
matter,' and this he asserts is continuous throughout the whole
body. If we desire to retain the use of the word cell to desig-
nate the li^'ing-tissue elements, we must regard each cell to
contain a net- work of living matter within it, and every cell
connected by threads of living matter with every other cell in its
neighl)orhood. . . .

* " Cellular Pathology, as based npou Physiological ami Patholojrical Histolotry." By
Rmlolf Virdiow. Translated from the second edition by Frank Chance, B. A.. M. B.. Cantab.,
«tc. New York : Robert M. DeWitt. Pp. 29, 40, et seq.

138 TISSUES IN GENERAL.

''Allow me to impress this fact upon you, that these are
things which each and every one of you can see for himself if he
only has a g-ood microscope, good eyes, and an unprejudiced mind.
Don't look for any so-called ' cells,' and don't imagine, as I used
to do, that it is given to only a favored few to be al)le to pene-
trate these mysteries of nature. The only danger is that you
become so much fascinated with histological investigations as to
neglect other important things.

" It is the merit of Heitzmann to have discovered, in the first
place, that the living matter in its simple form, as seen in an
amoeba, the so-called basis-matter of hfe, to which hitherto the
name of protoplasma has been applied, but which I propose to
designate as bioplasson, is not without structure, as has before
his accurate investigations been supposed, and that its structure
is that of a net-work, in the meshes of which the bioplasson fluid,
or the not contractile, not living portion of the organism exists.
He discovered that the gi-anules, which had been observed before,
are not foreign or accidental occurrences, but that they are part
and parcel of the Hviug matter — that, in fact, they are the thick-
ened points of intersection of the threads of bioplasson consti-
tuting the living net-work. Extending his investigations, he
found that wliat was true of the structure of liioplasson in the
amoeba, where a single unit-mass of living matter constitutes the
entire individual, is true of the structure of bioplasson of all,
even the highest, Mving organisms. The idea connected with the
word cell^ when this term was fh'st applied to the organic form
element, had, with the advance of microscopical and histological
knowledge, gradually undergone such changes that the name had
become a complete misnomer. Although ' cells ' were still spoken
of, it was imderstood that their essential constituent was li\dng
matter individualized into small, distinct masses. The existence
in these of a nucleus, a nucleolus, even a nucleolinus and gran-
ules, was known ; even thorns and processes had been observed
occasionally. But all this knowledge of the structure of these
elementary masses was fragmentary, until Heitzmann announced
that the nucleus, nucleolus, granules, and thi'eads are really the
li\dng contractile matter ; that it is ari*auged in a net- work con-
taining in its meshes the non-contractile matter which is trans-
formed into the various kinds of matrix characterizing different
tissues ; and that the tissue unit-masses of bioplasson throughout
the whole body are interconnected with fine threads of the same
living matter.

TISsrES IN GENE UAL. l;5!)

" On the si«jiiil1<'!iii('(' of these discoveries, aiid their ))eariiijjf
upon the questictn of physioh)gy and i)athoh)^y, I can liere say
but a few words. The more our knowledge of the minute
anatomy, or rather morphoh)»;y, of the orj^anism advances, the
more explieable beeomes the functional activity of the various
l)arts and tissues. So long as the cell was looked upon as the
simplest form element of the body, we could not hope to go
beyond the cells, and their performances in health and disease.
Unfortunately, their investigation could not exj)lain essential
vital i)henomena, the real activity of living matter. To-day we
have it in our power to examine almost all tissues of the animal
body while they are alive, ])y preventing, in thin sections placed
under the microscope, evaporation or drying upon the one hand,
and by supplying, on the other, such artificial temperature and
other conditions as are necessary for the yM'aX manifestation of
the particular tissue imder investigation. And, ena])led directly
to observe the phenomena which accompany movement of living
matter, its contraction, we may hope to attain clear conceptions
of the mysterious activity of muscles, of nerves, even of epithelia,
which form secretory organs. I may instance Heitzmann's dis-
covery of the manner in which primary muscle-bundles are
constituted, as showing how easy it is to understand the observed
phenomena of muscular contraction and innervation, if we have
correct information as to the morphological arrangement. With-
out going into the details, I may say that a primary bundle is made
up of rows of sarcous elements and muscle fluid, the former
united by threads of living matter, as mentioned before. Con-
traction of the whole muscle consists in this : that the sarcous
elements become larger, and the threads slnn-ter. Klihne has
shown that the motor nerve does not enter the muscle fiber, but
ends knolvlike at its side, in about the middle; here the con-
traction commences, and proceeds toward each end. In fact, we
find everywhere that definite physiological functions depend
upon definite moii^hological arrangements, and we may well
make deductions from the latter as to the former.

" Pathology will doubtless derive much advantage from the
bioplassou doctrine. We are enabled to observe quantitative
and quahtative changes of living matter in the smallest con-
stituents of the body. We know that the disposition of li\^ng
matter is different in different persons, and that, in the case of
increased supply of food, the reaction is different in strong and
healthy people on the one hand, and the sick and weak on the

140 TISSUES IN GENERAL.

other. Indeed, upon this knowk^d^e rests, to-day, the whole
doctrine of tnl)erculosis. It may he that we shall yet learn to
know the differences in the behavior of livin<; matter toward
different re-agents, or differences in its quantitative arrangement,
so that we may, perhaps, become able, from the examination
of a few colorless blood-corpuscles, to gain an insight into the
condition and ^•ital power of the whole indi\adual. If this come
to pass, it will be possil)le to recognize certain diseases by means
of the microscope before they are sufficiently developed to do
much hai-m ; and we may thus come a step nearer to the highest
aim of the physician — the prevention of disease. At all events,
every exact scientific investigation, even though at first of theo-
retical value only, sooner or later brings with it some practical
benefit."

The hopes here expressed have already, to a certain degree,
been realized, and the practical value of the new discoveries
demonstrated.

In 1879, I said in the introduction of an essay : *
'' I am far from ])laming any ph^'sician who, perhaps ten or
even five years ago, has studied microscopy, and left it disgusted
or in despair. The standard doctrine of ' cells ' and the ' cellular
pathology' was unsatisfactory indeed. Beyond the proof of
the presence of cells, microscopy did not advance, and the
examiners have been satisfied if they could see cells, the
greatly var^ydng shape and size and appearance of which
they had to admit, without knowing any of the causes of the
variations.

''To-day the cell-doctrine is surpassed ])y new discoveries.
Instead of looking at the shape of the cell, we have learned to
study the minute structure of its mass, the so-called protoplasm,
of which we know that it represents a constituent part of the
organism. Many of the morbid relations of the protoplasm have
been revealed, and made use of for practical purposes. We climb
upward upon the shoulders of the ingenious founder of the
cellular pathology, R. Virchow ; and that the new doctrine, for
which has been proposed the term ' bioplasson-doctrine,' has
really arrived at a certain point of })erfection, I presently intend
to demonstrate."

For the researches and deductions here alluded to, see
page 58.

* "The Aid wliieli Medical Diagnosis receives from Recent Discoveries
in Microscopy." Archives of Medicine, 1870.

Tisschs i.\ ^•y•;.\7•;/.•.ly.. 141

Tilt' iv-ajiH'iits which I used in ls7;{, with prcdih-ction, viz.,
tht' iiitnite of silver and chloride of j^old. are not ulvvays
relia]>le. and I admit, had my asserti<ms l)een Imscd exelusively
on specimens treati'd with tliese re-aj>vnts, they wouhl justly
have been considered as neai-ly woi-thless. Besides, a certain
amount of skill in nsinii' those re-ajicnts, and a well-trained eye,
are re([uiivd to see what really can be seen. This is evitlently the
reason why in Europe, of the many investigators who tried to
brin<'' to \'iew the connections of cartilai>'e-corpuscles after 1872,
when I first found these connections, only very few have suc-
ceeded. Still it was a])solutely necessary to demonstrate the
presence of such connections, because on cartilage-tissue have
mainly rested, for the last forty years, our biological views.

A. S])ina * deserves great credit for the discovery of a new
method, by which the connections of cartilage-corpuscles become
readily demonstrable even to a relatively untrained eye. This^
method is as follows: the cartilage, best from the articular ends
of l)one, for three or four days is placed in alcohol, cut and
examined in alcohol. '' We are satisfied," Spina says, " that from
the cells of the hyaline cartilage project solid offshoots ; these, as
is easily seen, arise from the l)odies of the shriveled cells, pervade
the basis-sidistance, and blend with the offshoots of other cells.
The thickness and number of the offshoots greatly vary ; the
most numerous and most delicate were found in specimens
from the superficial portion of articular cartilages of middle-
sized frogs," etc., etc.

From what I have seen, I can heartily recommend this method
for the demonstration of the connections, though it is, on account
of the shrinkage due to the preservation in alcohol, imperfect.
This method brings to view, also, the delicate, mostly rectangu-
lar reticulum in the basis-substance of fibrous connective-tissue
formations, adjacent to cartilage.

kS. Strieker t recently makes the follo^\'ing statements:

'^ The so-called migrating cells in the substantia propria of
the cornea, so far as can be ascertained by direct, continuous
observation, are neither migrating nor isolated cells. "VVe can
easily see, under suitalile conditions, that portions of their
bodies gradually assimie the looks of basis-substance, while new

* " Ueber die Saftbahnen des hyalinen Knorpels." Sitzungsber. d. Wiener
Akad. der Wissensch., 1870.

t " Mittheiluug liber Zellen uiid Grundsubstaiicen." Wieuer Mediz. Jahr-
biieher, IS SO.

142 TISSUES IX GENEBAL.

additions to the cell-body are formed from the neighboring basis-
substanee.

" The basis-substance, under favorable conditions, exhibits in
its interior form-changes like those of amoeboid cells. A net-
like arrangement, fi1)rill*, and other forms, come and go.
The basis-substance and the migrating cells in it represent a
continuous mass, which, according to circumstances, may assume
the featiu'es of basis-substance or of wandering cells. A lump
of this mass becomes a real migrating cell only if separated from
its surroundings, which, however, does not occur in the con-
tinuity of the substantia propria.

" The epithelia of the cornea, with their so-called cement-
ledges, likewise form a continuous living mass. Under favorable
conditions, we can easily realize that neither the cement-ledges
nor the cells are stal^le formations. The cement-ledges are
transformed into constituent parts of the neighboring cells, while
within the cells new cement-ledges arise, so that after a while the
configuration of the epithelium has changed, or else the whole
form of the cells of the anterior epithelium is lost to sight, and it
appears as a uniform mass, such as is the rule in the normal
living cornea.

" Changes of the branching cells in the substantia propria
are easily seen during the first few minutes after excision of the
cornea, by suitable methods of preparation.

'' The interior of the cell-bodies undergoes manifold visible
variations. One of the most remarkable instances is furnished
by the saliva-corpuscles. The assumption that a so-called molec-
ular motion takes place in the saliva-corpuscles, is eiToneous.
The gi-anules seen with insufficient amplifications are transverse
sections of trabeculae. The saliva-corpuscle is traversed by a
sharply marked trabecular structure (Balkenwerk), which, so
long as the corpuscle is fresh, executes lively wavy motions.
The waving gradually ceases on the addition of solutions of salts
in certain concentration, and the reticular structure disappears.
The wa\-ing is now replaced by very slow form -changes in the
interior mass."

VII.

CONNECTIVE TISSUE.

Definition and Division.

THE term counccilve tissue is applied to that tissue which con-
stitutes the frame of the body (skeleton), covers the articular
surfaces of bones (articular cartilag-e), incloses the whole body
(derma of skin), supports and surrounds muscles and nerves
(tendon, perimysium, perineimum), produces tlat layers for all
epithelial formations (basement layers), contains as a physiologi-
cal product fat-globules (fat-tissue), and forms the blood and
lymph vessels. It is composed of living- matter which, having a
reticular structure, contains in its meshes a lifeless, more or less
solid, interstitial basis-substance. At certain regular intervals the
reticulum is nodulated, and these nodules are the formerly so-
caUed connective-tissue cells, preferably termed connective-tissue
coi*puscles.

The distinguishing feature of connective tissue is the inter-
stitial hasis-substance, which is generally termed " glue-yielding,"
because some of its varieties on being boiled fiTrnish gelatine,
although other varieties, by the same treatment, yield a substance
which is not strictly glue, but kindred to it. For twenty years
(1840-1860) a lively controversy was carried on regarding the
relation between the basis or intercellular substance and the
plastids, the connective-tissue cells. Henle was the main repre-
sentative of the \'iew that the intercellular substance contains only

144 CONNECTIVE TISSUE.

cavities, while VltcIiow asserted that the intercellular substance
contains " cells," the seats of life. Between 1860 and 1870, his-
tologists began to be aware that the intercellular suV^stance
contains cavities, in which the cells are imbedded. Virchow^
in 1851, was also the first to recognize that all varieties of connect-
ive tissue belong to one group, for the designation of which he
proposed the rather unsatisfying term '' connective substances."

As A. Rollett * says: "The connective tissues are developed from the
middle germinal layer, in which blood and muscle also originate. The tj^neal
connective substances are recognized histologically by the circumstance
that they contain extensive and continuous layers of material (intercellular
substance), which, when compared with the cellular structures distributed
through its substance (protoplasma), or the morphological elements in other
tissues, always appears as a more passive suVjstance and one which participates
but slightly in the processes characteristic of life. These masses consist, for
the most part, of gelatine-forming substances, such as collagen, chondrogen,
and ossein. The connective tissues fi-equently pass by substitution or genetic
succession into one another; they appear, therefore, to be morphologically
equivalent, so that in many instances certain organs, or parts of organs,
belonging to animals nearly allied to one another, are formed sometimes of
one, sometimes of another, of these tissues."

The basis-substance, the hitherto called intercellular substance^
is a product of the lifeless bioplasson liquid which, probably
nitrogenous from the very beginning, is transformed by chemical
changes into the nitrogenous, more or less solid, mass termed
basis-substance. In the same variety of connective tissue, espe-
cially in the fibrous, the basis-substance may exhibit different
degrees of solidification. Bundles of fibrous connective tissue are,
f. i., built up of striated, glue-peldiug hasis-sxhsfanre ; the
bundles are separated from each other by the less solid cement-siib-
stance ; and they are bounded, both at their peripheries and around
the plastids, by a more solid, dense, and chemically indifferent
elastic suhstdnce. The so-caUed elastic fibers are but a variety
of the glue-yielding basis-substance, in a high degree of solidi-
fication.

According to the nature of the interstitial substance, the
morphological properties of which are far better known than the
chemical, we may distinguish four varieties :

Myxomatous or mucoid basis-suhstance, a jelly-like, translucent
substance, not yielding gelatine ;

■' "A Manual of Histolop3'," by S. Strieker. American translation edited by Albert H.
Buck, 1872. Chapter : " The Connective Tissues."

CONNECriVK TISSUE. 145

Fibrous basis-suhsfaiirc, a somi-solid, opiKpic sul>staii(M', diar-
actorizt'd 1)V a striatrd, fibrous, or laiiicllated appcaraiiec', yielding,
on bt'ing boiled, ^\ne or a substance kindred to glue ;

CorfiltK/iiioiis or rho)i(h'o(/('iious h(isissuhsf(inri\ii dense, opaque
sul)stanee of a uniform hyaline or striated appearance, which
on being boiled also yields a liquid kindi'ed to glue, as indicated
by its odor ; and

Osseous or bony hasis-siibstance, a dense, opaque, glue-yielding
substance, of a striated or laniellated appearance, infiltrated
"with lime-salts.

The character of any variety of connective tissue is exclu-
sively defined by the character of its basis-substance, whereas the
connective-tissue corpuscles, though greatly varying in size and
shape, are all essentially the same, viz. : living matter hitherto
called *' protoplasm." These protoplasmic bodies, plastids, as a
rule nucleated, lie in cavities of the basis-substance, representing
what has been termed the '^ fixed cells " of connective tissue. Be-
sides, in some varieties of connective tissue, plastids are met
with which, under favorable conditions, exhibit rapid changes of
shape and locomotion. Von Recklinghausen* first drew attention
to the presence of these " migrating cells." Such corpuscles can
change their location only in the interstitial liquid portions of the
basis-substance. Their presence is by no means the rule.

Of the connective-tissue corpuscles, of coui'se the '' fixed cells "
alone are united with each other. In myxomatous tissue the cor-
puscles are connected by thick and wide offshoots, constituting
the " stellate cells" of Virehow. In hyaline cartilage the union is
by delicate offshoots ; while in the fibrous tissue, in fibrous car-
tilage and bone, the corpuscles are joined by both thick and slender
offshoots. The basis-su])stance, w^hich was formerly supposed to
be structureless, is to-day known to be traversed by a delicate
reticulum of li\4ng matter, the meshes of which are somewhat
larger than that of the plastids ; by means of this reticulum the
connection between the plastids is established.

The reason why the reticular structure of the basis-substance is not, or
so little, marked in the fresh condition of the tissue, is that there is not
sufficient difference between the refracting power of basis-substance and of
living matter. It can be brought to \'iew either by staining re-agents, such as
nitrate of silver and chloride of gold, or by alteration of the refraction of
the basis-substance, such as its liquefaction in the inflammatory process or
deposition of lime-salts. The latter occurrence, both in normal and morbid

* Yirchow's Ai-chiv. Bd. xx\Tii.

10

146 CONNECTIVE TISSUE.

conditions, is an excellent means to render the reticulum in the basis-
substance of cartilage visible, without any re-agent. In gi'ound specimens
of dry bone the canities (lacunte) and their offshoots (the canaliculi) are very
marked, especially if filled with air or other extraneous matter, because the
difference in the refraction of the calcified basis-substance and the cavities,
deprived of their bioplasson, is very great. The more the lime-salts are
extracted from the basis-substance — f. i., by a solution of chromic acid,
which at the same time preserves the bioplasson — the less visible are the
cavities and theii* offshoots. A small amoxmt of lime-salts, left behind even
after chromic-acid treatment, renders both cavities and canaliculi, both the
bone-corpuscles and their offshoots, plainly visible.

The development of basis-substance invariably takes place
from the bioplasson liquid. Either single plastids are infiltrated
with basis-substance and rendered pale, apparently structureless,
or the process takes place in a number of coalesced plastids, from
which the formation of a territory results. "Within this territory
unchanged plastids are left, the connective-tissue corpuscles
proper. The first manner of formation of basis-substance occurs
in the simplest and earliest varieties of m^^omatous connective
tissue, the latter manner in all higher developed forms of
fibrous, cartilaginous, and bony connective tissue.

(1) Myxomatous or Mucoid Tissue. Mj^omatous tissue is the
earliest connective-tissue formation in the embryo, and all later
varieties of connective tissue arise fi'om this. As soon as the
mesoblast is produced, we recognize it by the presence of numer-
ous plastids, uniform in size and shape, some homogeneous,
others granulai- and nucleated. All are connected by means of
delicate filaments, traversing the light rim around each plastid.
This tissue is called the emhryonal or indifferent tissue, the latter
term meaning that no difference can be discovered in the char-
acter of the plastids.

During the first few weeks of embryonal life we meet vrith
myxomatous connective tissue only, and also during the entire
period of intra-uterine development this kind of tissue largely pre-
vails ; it also forms the tissues destined for the attachment of the
embryo to the woml) and for its nutrition, viz. : the placenta and
the umbilical cord. With advancing development of the body
the myxomatous tissue is replaced by more advanced formations,
and in the full-gTown individual only the vitreous body of the eye
exhibits features similar to those of the umbilical (?ord ( Yirchow).
We also meet ^vith it in all remnants of embryonal development,
such as medulla of bone, adenoid or lymph-tissue (l^anph-ganglia,
spleen, submucous adenoid layers), and tooth-pulp.

rOXXh'f -77 \ 'K TISSVE.

147

Fig.

^mm: i^^...

•47. — Medullary Tissue of Chest
Human Embryo, Four Weeks Old.

C, meil Hilary tissue, probably tending toward the forma-
tion of cartilaf;e of ribs ; P, medullary tissue, probably tend-
injr toward the formation of fibrous perichondrium. Mafmi-
lied GOO dianietei.s.

Ill tlic aiiiiiml oi-j^aiiisin, niyxomatous tissue appears in tlic
l()ll()wiu«if varieties :

(a) MednUarji Tissue, fouiid in nicdiilla of Ixme at an early
sta*;*' of (IcNM'lopiiient. Tlic limnaii ('in)>rvo exhibits tliis tissue
in tlie Hrst few weeks.
Plastids, either solid,
or gfrauular and nu-
cleated, i^lobular or
spindle-shaped, and
of varying size, are
scattered in a scanty
jelly-like basis-sul)-
stance. This siili-
stance, examined
without any re-agent,
looks granular with
lower powers of the
microscope, but with
high powers exhil)its
a delicate reticulum,
which blends with
the delicate, tlu*ead-like offshoots from the plastids. Each field
of the liasis-substance corresponds in size and shape to one plastid
or to a small group of plastids ; the earliest formations of basis-
substance arise from single plastids, by a chemical alteration of
the bioplasson liquid, without the formation of territories. (See
Fig. 47.)

The medulla of bone exhibits this variety of myxomatous
tissue at the fourth and fifth month of embryonal life of man,
and in the case of pup or kitten at the corresponding stage, viz. :
time of birth.

Fig. 33 represents this tissue in a chromic-acid specimen ;
Fig. 34, stained with chloride of gold, in order to demonstrate
the structure of the basis-substance.

The plastids in medullary tissue often assume the spindle
shape, and here, too, we are satisfied that every field of basis-
substance arose from an original plastid, without formation of
territories. The embryonal and the medullary tissue in both va-
rieties are prototypes of tumors, termed " round-cell and spindle-
cell sarcoma" (globo and spindle myeloma). (See Fig. 48.)

(h) Reticular Tissue. This is the next stage in the development
of mvxomatous connective tissue. It consists of a reticulum of

148

CONNECTIVE TISSUE.

either plastids or fibers, with nuclei at their points of intersec-
tion, inclosing a jelly-like basis-substance. The center of a field
of basis-substance often contains a nucleus, which indicates that
the field has originated from a plastid, the peripheral portion of
which, by a chemical change of its liquid, was transformed into
basis-substance, while the nucleus remained unchanged.

The placenta is, to a great extent, composed of this tissue,
the reticulum being of a fibrous character, while distinctly nucle-
ated plastids, the so-called " decidua-cells," fill the mesh-spaces of
the reticulum.

The villi of the placenta consist of a reticulum of plastids
with thickenings at the points of intersection, in close connection

Fig. 48. — Medullary Tissue of Bone from the Scapula of a
New-born Kitten.

£, bone-tissue ; 8, myxomatous tissue composed of spindle-sliapeil plastids, traversed by
a capillary blood-vessel. Magnified 800 diameters.

with the endothelial wall of the capillaries. Most of the mesh-
spaces exhibit central nuclei. (See Fig. 49.)

The tissues of the body, which after more advanced develop-
ment show the structure of fibrous connective tissue, are origi-
nally reticular. In many instances we encounter in very young
embryos spaces, inclosed by a fibrous or plastid reticulum, which
contain a jelly-like basis-substance, too large for admitting them
to have originated from a single plastid. In some other instances

CONNECTIVE TISSUE.

149

of n'ticuhir tissue no doubt a single plastid has become l)asis-
substance, but here two or more plastids must have coalesced
in order to jiroduce a nucleated field of basis-substance — the
first evidence of a tei'i'itoiy. Formations of both these varie-
ties, however, may oecui- in one and the same specimen. (See
Fig. 50.)

Fig. 49. — Reticular Myxomatous Tissue of a Villus of the
Placenta of a Humax Embryo, Four Months Old.

EE, epithelial cover of the villus ; S. solid bud of a growing villus ; CC, capillarj- blood-
vessels, overlapped bj- the myxomatous reticulum. Magnified 500 diameters.

The lymph-ganglia, including the thymus of embryos and the
spleen during the whole of life, exhibit the reticular mj^omatous
structiu-e in a mai'ked manner. (See Fig. 31.) The reticidum is
either fibrous or composed of nucleated branching plastids,* while
the meshes, varying gi-eatly in size, contain plastids, either single
or in gi'oups, in aU stages of development : the lymph-coii)uscles.
Of this variety of lymph-tissue the substance of the th\Toid body
may perhaps consist, although the spaces holding the lymph-

* C. Toldt has demonstrated that in the thj-mus of low vertebrates (frog,
newt) the reticulum retains its protoplasmic chax-acter for life. Lehrbuch
der Gewebelehre, 1877.

150

CONNECTIVE TISSUE.

corpuscles in that substance are closed alveoli, and the walls of
the alveoli are distinctly fibrous in character.

The reticular myxomatous tissue of the lympli- ganglia is the
prototype of tumors termed Myxo-Sarconia (Myxo-Myeloma).
The more advanced tissue of the character of the thyroid body
is found in all formations called lymph-adenoma. Some histolo-
g-ists claim that the connective tissue which surrounds the epi-
thelial formations in the kidneys, in the salivary glands, and the
connective tissue in the central nervous system, are reticular in
structure. M. Schultze found this structure in the retina.

Fig. 50. — Reticular Myxomatous Tissue of the Muscle-fascia
OF A Human Embryo, Two Moxths Old.

E, reticulum of plasties, or fibers with oblong nuclei at tlie points of intersection ; M,
striped muscle at an early stage of formation; C, capillary blootl-vessel ; T', vein. Magiii-
tied 500 diameters.

(c) Myxomafons Tissue of the UmhUkal Cord. Virchow discov-
ered in 1851 that the umbilical cord, formerly considered as a gela-
tinous formation (Wharton's jelly), is a regular mucoid tissue,
traversed by a delicate reticulum of branching cells, in the meshes

CONNKCTIVI': TISSUE.

151

of which is (h'])(>sit('(l tin' jclly-likr " iiitfrcclluhii' " siiltstaii<-c. In
this substance globiilai- and isolated cells occiii-. X'irchow found
that, Ix'sidt's the thrcr main blood-vessels (two artcrii's caiTyiiij;
venous bhxxl, and oiu' vein cari'vinj^" arterial l)h)od), there ai-e no
othi'r vessels thron^hout the entire length of the umbilical cord.
Cai)illaries exist only at a short distance (a})ont one-lialf inch)
close al)ove the insertion of the cord into the abdominal wall.
Mrcliow draws attenti<ni to the heavy coats of the vessels, the
muscular character of which was discovered afterward l^y
Kiilliker, and concludes that these coats play an important part
iji the occlusion of the vessels whenever they are severed or torn,

■ CuCCfiN.t.

Fig. 51. — Segment ok iuk l .muu-kal (Okd of a Human Embryo.
Four Months Old, in Transverse Section.

A, artery; V, veili; M, mj'xoiiiatous tissue, the common adveiititia; i', ei>itlielial cover.
Magiiifie<I 25 diameters.

without ligature. The mucous tissue, Virchow * says, is attached
to the imperfectly developed adventitial coat of the three vessels.
In my conception the umbilical cord in into is the adventitial
coat, common to the three blood-vessels, of which tlie vein, as a
rule, has a much narrower muscle-coat than the two arteries.
(See Fig. 51.) No capillary blood-vessels and no lymphatics have
been discovered in this tissue, neither is anything certain in re-
gard to nerves, though it is probable that the three vessels are

* "Die Cellularpathologie." Vierte Auflage. Berlin, 1871.

152 CONNECTIVE TISSUE.

under the control of vasomotor nerves. The myxomatous tissue
is often found to contain spaces, greatly varying in size and num-
ber, filled with liquid ; these, doubtless, are secondary formations,
so-called cysts. The outer surface of the umbilical cord is
covered by a single layer of flat epithelia.

Now, if we compare a transverse section of the umbilical cord with an
amoeba (see page 21), the similarity between the two becomes evident.
The epithelial coat of the cord con-esponds to the continuous layer of living
matter in amoeba ; the complex reticulum of plastids corresponds to the
simple reticulum of living matter in the amoeba ; the closed cavities of the
blood-vessels holding isolated plastids, the blood-corpuscles of the cord, cor-
respond to the closed spaces, the vacuoles containing isolated gi'anules of
living matter. In fact, the simple amoeba is the representative of the com-
plex structure of the umbilical cord, as well as of all other tissues of the
human body. ,

Fig. 52. — Umbilical Cord of a Human Fcetus, Nine Months Old.
Chromic Acid Specimen.

P, bioplasson cords with nuclei at their points of intersection ; B. partly homogeneous,
partly fibrous, l>a8is-sul)8tanc(^ Magnified 500 diameters.

With lower powers of the microscope we recognize in sec-
tions of the umbilical cord of a fully developed himian foetus, both
fresh and preserved and hardened in a chromic acid solution, a
relatively coarse reticulum of plastids, Virchow's branching cells.
The best sections are obtained from the portion about midway
between the vessels and the surface, because nearer the vessels and
the surface the reticulum, being very dense, does not admit of dis-
tinct demonstration. We see ramifying so-called protoplasmic
strings of a delicate granular structure, containing oblong nuclei

CONNECTIVE TISSUE.

irj3

usually at the points of intersection.* In the meshes the l)asis-sul>-
stauee is in part homogeneous, in part traversed by delicate fibrillar.
Not infreciucntly a. nucleated strin<i' passes directly into a bundle
of tibrilla'. In the center of a mcsh-s})acc wc encounter sometimes
a jjlobular plastid, apparently isolated — /. e., unattached to the
strings forming the reticulum. (See Fig. 52.)

If we rub a stick of nitrate of silver over the surface of a
piece t)f a fresh umbilical cord, it will soon become brown
on exposure to daylight. Sections from such an umbilical
cord will show light, brautihing spaces in a dark brown basis-

FiG. 53. — Umbilical Cord uf a Human Fietus, Nine Months Old.
Stained with Nitrate of Silver.

.5, liglit spaces, corresponding to the bioplasson cords in Fig. 52, branching and anas-
tomosing; B, dark brown basis-substauce, indistinctly striated aud granular. Magnified
500 diuniet<>rs.

substance. The light spaces correspond in size and shape to the
strings seen in specimens preserved in chromic acid. They anas-
tomose, and some of them send into the basis-substance smaller
branches, which often divide and subdivide so much as to show a
delicate, pencil-like appearance. The contours of the light spaces
and their branches are in many places serrated. The brown

* In the umbilical oord of the pig-foetus the nuclei of the cord are much
more numerous than in the human.

154

CONNECTIVE TISSUE.

basis-substance appears indistinctly striated and granular. (See
Fig. 53.)

If we expose a piece of the fresh umbilical cord for some
hours to the action of a large quantity of a one-half per cent,
solution of chloride of gold, the specimen assumes in the daylight
a dark violet color. Sections exhibit branching and connecting
strings of dark violet color, whose nuclei at the points of inter-
section are either black or pale violet, while the basis-substance
is but faintly stained either pale violet or pink. The strings in
their general features and size correspond both to those seen in
specimens preserved in chromic acid and to the light spaces
found in specimens stained with silver. The pale basis-substance

— p

Fig. 54.

-Umbilical Cord, of a Human Fcetus, Nine Months Old.
Stained with Chloride of Gold.

P, dark violet bioplasaon cords, corresponding to tliose in Fij?. 52, and to the light
spaces in Fig. 5'i; B, i)ale pink basis-svibstance, indistinctlj" striated. Magnified 500
diameters.

exhibits an indistinct striation, and some smaller offshoots from
the violet strings pass into and are lost in striated bundles.
(See Fig. 54.)

By comparing the chromic-acid, the silver-stained, and the
gold-stained specimens, it is apparent that the light spaces are
identical with the violet tracts, and these again identical with
the bioplasson strings of the unstained specimen. In other

CONNECTIVE TISSUE. 155

words, tlu' nitrate of silver has stained the myxomatous basis-
substanee, and left the strings unstained, whereas the gold has
stained the strings very mueh, the basis-substanee, on the eon-
trary, very litth'.

These faets eonvinee us that Von Keeklinghauscn's tlieory,
that lymph-spaees traverse the basis-substance and contain
cells, is erroneous. The spaces produced by silver stain are
not lympli-spaces, but l)iop]ass()n spaces, viz. : they are the
biophisson itself, unstained, or the cavities containing the
unstained bioplasson. Unquestionably, such light spaces in
silver specimens of various other tissues anastomose with the
light spaces of the lymphatics, as bioplasson formations (plas-
tids) are directly attai^hed to the walls of the latter, and neither
are stained by nitrate of silver. For further details of the
minute structure of the umbilical cord I refer the reader to page
120, and to Fig. 35 and Fig. 36.

The (larhpiiicut of the myxomatous tissue of the umbilical cord has not
as yet been sivfficiently studied for any positive statement. Of the minute
structure of the vitreous body very little is known. From what I have
seen in gold-stained specimens, and in the changes that occur on the borders
of tumors of the choroid growing into the vitreous, I am convinced that the
plastids of the vitreous body, most numerous at its peripheral portions, send
delicate offshoots of living matter into the myxomatous basis-substance, which
is alive throughout and liable to active morbid changes.

The myxomatous tissue of the pulp of the tooth will be dwelt upon in the
chapter treating of teeth.

Fat-tissue. Our knowledge of fat-tissue is very limited. The
main facts are as follows :

Fat-granules may arise from any bioplasson granule in
isolated plastids and in plastids producing tissues of any descrip-
tion. The granules of living matter assume a higher degree of
luster and increase slightly in size whenever they are about to
change into fat-granules. As I have observed in colostrum cor-
puscles, the fat-granule at first remains connected by delicate fil-
aments with the rest of the reticulum, and S. Strieker has
observed that on the heating-stage fat-granules are expelled
from a colostrum corpuscle. (See page 28.)

The chemical change by which the nitrogenous substances
are converted into fat is not understood. It is even possible,
according to a suggestion of L. Elsberg, that the plastidides are
not directly transformed into molecules of fat, but are only
mixed with them, so that in early stages of development of fat.

156 CONNECTIVE TISSUE.

the plastidules may, by a retrograde metamorphosis, be reestab-
lished in their original structure. *

The fat-tissue met with in other varieties of connective tis-
sue, chiefly the fibrous, consists of a number of fat-globules,
aggregated into groups, which are termed fat-lobules. Such
formations are seen, in greatly varying amount, in the subcuta-
neous tissue, the female breast, the omentum, and around the
heart and the kidneys. The lobules being freely supplied with
capillary blood-vessels, besides these contain only a small amount
of a delicate fibrous connective tissue between the fat-globules.

Fat-globules, which vary greatly in size, are inclosed by a
delicate continuous layer, termed the capsule of the globule. In
this capsule there is almost invariably found an oblong, nucleus-
like body, which in edge view appears to be fusiform, and blends
with the capsule. The fat substance proper contained in the
capside is semi-fluid, and can be pressed out on artificially ruptur-
ing the capsule. Alcohol renders the fat coarsely granular, and
causes it to shrink. Chromic acid solution, after a certain length
of time, produces vacuoles in the fat-globule. Turpentine and
oil of cloves dissolve the fat, and the nucleated capsule becomes
plainly visible after the application of these re- agents.

In fat-globules preserved for a period of several months
in a one-half per cent, solution of chromic acid, J. A. Rockwell,
in my laboratory, discovered bioplasson masses in the middle of
the fat. These masses, as a rule, appear coarsely granular with
lower powers of the microscope, often branch, and sometimes
contain a central nucleus-like body. High amplifications show
that the granules and the nucleus are interconnected by means
of delicate filaments. It also occurs that the bioplasson forma-
tion is flattened out near the capsule, or its granules are scattered
at greater distances through a portion of the fat. Small globules
contain one such granular formation, while large globules may
hold two or more in addition to a varying number of scattered

* According to L. Eanvier ("Des Lesions du Tissu Cellulaire Kiehe dans
l'(Edeme,"Comptes Eendus, 1871), in oedema produced by ligation of tlie vena
cava and discision of one sciatic nerve of dogs, the connective tissue infil-
trated -wdtli serum, twenty-four hours after the beginning of the oedema,
shows cells, the peripheral protoplasma of which contains gi-anules of a fatty
appearance. Their refracting power is lower than that of fat, but if treated
with a weak solution of chromic acid or bichromate of potassa, they become
more highly refracting and smaller. These peripheral gi-anules seem to be
composed, he says, of fat and an albuminous substance, just as in the devel-
oping fat-cells.

CONNECT] VP: tissue. 157

granules. Tho «;r!uuil('s lu-c, in most iiistaiicos, of a dim, j^i'ay
color, and readily distinguished from tlu! surroundinji; yellow
fat. These formations are evidently those long known in
speeinu'ns obtained from emaciated persons, and preserved in
alcohol, as the nucleated, stellate })rotoplasmic bodies within the
cai)sulc. The intra-capsular [u-otoplasm, according to 0. Toldt,*
retains its vital contractility even in the highest degrees of
emaciation, and from it starts, under favorable conditions, the
fornuition of new fat.

Fat-globules often contain a coloring matter, either diffused
or in the form of pigment-granules ; and even in the fresh con-
dition they may contain needle-like formations, usually termed
margaric acid crystals. More recent chemi(!al researches show
that these crystals are much more complicated formations of fat-
acids than was thought formerly. Such crystals are frequently
seen in rancid fat, where they produce large, dark clusters of
radiating needles, standing out like the bristles of a porcupine.

Fat-globules originate from indifferent or embryonal plastids,
which are considered by C. Toldt to be specific fat-formers. At
first small granules of fat appear, which by coalescence produce
globules. It has l)een maintained that each plastid will furnish
a complete fat-globule, often of large size ; whereas the researches
of Flemming, Czajewicz, and others make it highly probable that
a number of plastids are fused together in order to produce
a large fat-globule. Flemming drew attention to the fact that,
in highly emaciated fat-tissue, cells are often found which
exhil)it a proliferation of their nuclei, and even contain a large
number of "young cells." He terms this condition the "pro-
liferating atrophy," in contradistinction to the simple " serous
atrophy." Czajewicz asserts that the fat in rabbit disappears
after a few days' abstinence from food, but rapidly re-appears
in the original globules upon the resumption of abundant feed-
ing. The substance which under these conditions replaces the
fat is said to be serum or mucus. In inflammation, the same
observer noticed a splitting of the fat-globules into numerous
plastids.

From all these facts we ma}^ conclude that fat-tissue is closely
allied to myxomatous connective tissue, although the metamor-
phosis in each is materially different. A certain number of
plastids changed to fat may coalesce into what we know to be
a territory, in which unchanged portions of bioplasson are left.

* Lehrbuch der Gewebelehre. 1877.

158 CONNECTIVE TISSUE.

Around the territory a connective-tissue capsule originates, in
a way similar to the formation of the myxomatous reticulum of
fibers, and the nucleus in the capsule of the fat- globule is analo-
gous to the nuclei found at the points of intersection of the
myxomatous reticulum.

(2) Striated or Fibrous Connective Tissue. The term " connect-
ive tissue" was employed by Johannes Miiller, in 1835, for desig-
nating the tela ceUulosa of older anatomists. B. Reichert, in 1845,
first maintained the continuity of this tissue, and, considering
it to be structureless, attributed the fibrous appearance to the
presence of folds or striations. Virchow, in 1851, demonstrated
the presence of corpuscles, the supposed hollow and so-called
" connective-tissue cells," imbedded in the fibrous intercellular
substance ; and W. Kiihne, in 1864, proved by the means of
electricity that these corpuscles possess vital properties — viz.,
contractility.

At present we know that the tissue corpuscles, being bioplas-
son formations, are imbedded in cavities of the basis-substance.
The latter is CTninently glue-yielding, and composed of numerous
delicate spindles, arranged in lines. It is only after teasing of
the specimen that an isolated fiber is discovered, while in the
continuity of the tissue isolated fibers are not observed.

We know, furthermore, that the fibrous basis-substance (syn-
onymous with the matrix and intercellular substance of former
histologists) is traversed by a delicate reticulum of living matter,
whose meshes present an almost uniformly rectangular arrange-
ment. This reticulum is visible within delicate bundles in speci-
mens preserved in chromic acid, without the addition of any
re-agents ', or in other specimens by the use of re-agents, as
described before (page 122). The alcohol treatment (page 141)
also serves for bringing the reticulum to view.

The basis-substance varies greatly in its degrees of density.
It is very dense in the tendon, the sclerotic, the cornea, and less
dense in the formations termed " loose connective tissue." The
delicate spindles, which constitute the fibrillae by coalescing in a
longitudinal du"ection, are separated from each other by a less
dense so-called cement-substance, while bundles of fibers are
separated from each other by a more liquid substance, which, as
a rule, contains, besides the blood-vessels and lymphatics, numer-
ous plastids, all being connected with each other as well as with
the walls of the vessels and the reticulum in the basis-substance
proper. In some varieties of this tissue the basis-substance.

CONNFJ 'TI\ 'J'J TISS 1 7<;. ] 59

insti'iul of bi'iii^ fibrous, is coiniKKsod of ril)l)oii-lik<' foriii.itioiis,
as in till' {x'l-iosti'um ; and in otluTS it is disposed of in flat
layers, as in the corncii. In many instances we meet with an
extremely dense basis-snl)sfanee, termed the elastic substance,
which either occurs in the shape of fibers at the boundary of
territories, or almost entirely replaces the ^'lue-yieldinf^- l)asis-
substance. This formation ajjpears in the shape of either a dense
reticulum or a uniform flat layer. Examples of fibrous elastic
basis-substance are found in the ccmnective tissue of the derma
of the skin, in the periosteum, etc. ; examples of an elastic retic-
ulum arc furnished by the Lig. nuchsB, the adventitial coat of
arteries, etc. ; examples of flat elastic layers are found in all the
so-called '' hyaline or structureless membranes," beneath epithe-
lial and eiulothclial formations, in the sarcolemma, etc.

The different varieties of fibrous connective tissue may be
classified according to the following characteristics :

Delicate bundles of fibrous tissue, running mainly in one
direction, and being separated by a basis-substance of slight
density, form the so-called loose connective tissue — f. i., in the
omentum and the arachnoid;

Bumlles of fibrous connective tissue, interlacing in all direc-
tions, produce a felt- work structure — f. i., in the derma, the
interarticular ligaments, the sclerotic ;

Coarse bundles arranged in onl}' a longitudinal direction are
found in the tendons and in the articular ligaments ;

Flat bundles transformed into ribbons, freely interlacing,
appear in the periosteum, the dura mater, the pericardium, and
the aponeuroses ;

A coalesced layer of elastic basis-substance produces a flat,
sheet-like formation — f. i., in the hyaline or basement layers, and
in sarcolemma ;

Lamellated layers of considerable breadth, freely interlacing,
build up the cornea.

(a) Delicate Connective Tissue Composed of Fibrilhe, or of
Compdrativehj Thin Bundles of Fibrilhe. This variety, usually
termed " loose connective tissue," is arranged in bundles, in which
the fibers are connected by a small amount of a cement-sub-
stance, soluble in lime and baryta water. Between the bundles
are spaces which contain either a semi-fluid, \'iscid, myxomatous
basis-substance or a l^'mph-like liquid. These spaces may become
expanded by accumulation of a serous liquid, as in oedema, or of
air or liquids introduced from without.

160

CONNECTIVE TISSUE.

The plastids in the bundles are flat corpuscles, either irreg-
ularly scattered or presenting a chain-like arrangement ; these
bodies are frequently small, not surpassing the size of nuclei. In
the mj^omatous portion, however, they are larger, and have
coarse offshoots, sometimes directly joining in a stellate form.

The myxomatous portion
may also contain, in a
varying number, the " mi-
grating cells" of Von
Recklinghausen and the
coarsely granular " plas-
ma-cells" of ' Waldeyer, es-
pecially in the neighbor-
hood of capillary blood-
vessels. Their significance
is not yet understood, nor
is their presence constant.
The delicate bundles, if
treated with dilute acetic
acid, swell and are con-
stricted in such a manner
as to give the bundle an
■^^^^ hour-glass or rosary-like
^\£'\ \ \ appearance. These con-
^^ ^^ strictions are due, accord-
FiG. 55.— Arachnoid op the Spinal Cord ing to Henle, to the pres-
OF AN Adult. enceof elastic fibers twined

around the bundle, which
are not acted upon by the
acetic acid. Their origin
is explicable, as I shall
show hereafter, by the formation of territories, a number of
which compose the bundle, while at the boundaries of the ter-
ritories the basis-substance is solidified into elastic substance.
A. Rollett maintains that the elastic fibers are offshoots of cells
similar to the reticular variety of connective tissue ; according to
Franz Boll, these ceUs, originally twined around the bundle in
shape of a reticulum, fuse in advancing development into an
elastic membrane, wliich envelops the bundle and exhibits linear
thickenings, branching after the manner of veinlets in leaves.

The best examples of loose connective tissue are the arach-
noid and the trabeculae traversing the sub-arachnoideal space.
(See Fig. 55.)

Delicate buutUes of fibrous connective tissue, B,
run in different directions and contain very small
idastids in the sliai)e of oblong nuclei. Tlie inter-
stitial basis-substance slightly fibrous. E, a portion
of the covering endothelium. Magnified 500 tUams.

CONNECTIVE TISSUE.

161

In serous iiu'iiil)i-aiK's, especially in tlic (Hiiciitimi, the delicate
hundles of fibrous connective tissue are arranged in the shape of
a roticuluin, the meshes of which are very hwfro, constitutinj^
what has l)een termed ''areolar connective tissui^" (Hassal).

The fibrilliV, com])')sino- delicate bundles, freely interhu^e in
the i)apillai'y layer of the derma of the skin, and in the mucous
membranes; while in the subcutaneous tissue the bundles are
coarser and their interstices contain the fat-lobules. Similar
features are observed in the loose connective tissue around the
eyeball and in the female breast.

The delicate bundles of the pia mater are also interlaced, and
generally enter the gray cortex of the brain and the white cortex

Fig. 5G. — Delicate Fibrous Connective Tissue from the Border
OF the Thyroid Cartilage of a Young Man.

C, cartil.nge ; B, V. blood-vessels in transverse ami oblique section ; G, dense tibious con-
nective tissue. Masuified 800 diameters.

of the spinal cord in radiating directions. They are freely sup-
plied with blood-vessels in their interstices, and upon entering
the nervous tissue gradually divide, and their fibers form a delicate
reticulum which supports the nerve-formations, the '* neuroglia "
of Virchow.

In muscle, a delicate loose connective tissue is found around
the muscle-fibers and their bundles (perimysium internum and
11

162

CONNECTIVE TISSUE.

extermim) ; this tissue, especially in its juvenile condition, is
freely supplied with large and branching plastids.

Delicate fibrous connective tissue is often largely intermixed
with other varieties of connective tissue in the form of either
scattered fibrillaB or interlacing bundles of fibrillae. It blends
with the true myxomatous tissue, as well as with the dense
fibrous varieties. Bundles of the latter, in the tendon and the
interarticular ligaments, are suiTounded and inclosed by loose

ill a J. Iv- \ I.;l„j;...

Fig. 57. — Ixterarticular Ligament from the Knee-joint of a
Grown Dog.

L, bundles cut in a lonjatndinal direction: C, bundles cut in a transverse direction; P,
the nucleated, finely granular x)lastids forming- a continuous laj'er around tlie bundles. Mag-
nified 500 diameters.

connective tissue, which is the exclusive carrier of blood-vessels.
(See Fig. 56.)

fbj Dense Connecfice Tissue composed of Coarse Inferlacing
Bundles. The essential feature of this variety is the presence
of comparatively coarse bundles, which, interlacing either
at right angles or in an oblique direction, produce a very

CONNECT I \ E TISS UK.

lG:i

bundles exhibit
often reduced t<»

scattered

the size

firm and dense felt-woi-k. Tlu
obloni; or spindle-shaped plastid;
of nuclei. The interstices be-
tween the bundles, the inter-
fascicular si)aces, l)eing- filled with
a more or less lit^uid substance,
contain a continiu)us layer of
plastids and a few blood-vessels.
The bioplasson is freely supplied
with nuclei, and by its arrange-
ment between and around the
bundles presents a reticiduni simi-
lar to that in the myxomatous tis-
sue of the umbilical cord, the dif-
ference being- that in the latter
the meshes contain a jelly-like,
myxomatous basis-substance, in
the former a solid, fibrous one.
The peripheral portions of the
intervertebral disks and the inter-
articular ligaments are examples
of this tissue. We may cut
through such a tissue in any di-
rection, and invariably meet with
longitudinal, oblique, and trans-
verse sections of bundles. While
the longitudinal sections exhibit
a dense striation or fil^rillation,
the transverse sections look ho-
mogeneous or slightly dotted, cor-
responding with the transverse
sections of the fibriQae. (See
Fig. 57.)

In the derma of the skin, the
bundles or groups of bundles are
coarser the nearer they are situated
to the subcutaneous tissue; to-
ward the surface they gradually

become finer, and in the UT)permOSt 1">'^'-- contaimu- m.mer<.u8 i.igmeut grau-
' ^ ^ ules. Maguifleil 500 iliaiueters.

portion, the papillary layer, the

bundles are extremely delicate. In the derma, too, the bundles

are separated from each other by a continuous layer of nucleated

Fig. 58. — Sclerotic of the Bull's
Eye. Vertical Section.

L, buudles cut in a longitudinal direc-
tion ; T, bundles cut iu a transverse direc-
tion; O, bundles <'ut in an obli(|ue direction :
P, the continuous interstitial bioplasson

164 CONNECTIVE TISSUE.

plastids, and in this layer scanty capillary blood- and lymph- ves-
sels are found. Both blood- and lymph-vessels ramify the more
the nearer they approach the surface, so that the papillary layer
has the greatest nujnber of vessels. In every du-ection we meet
with longitudinal, oblique, and transverse sections of bundles, the
latter being characterized by a doll luster and a homogeneous or
finely dotted appearance. At the periphery of the bundles we see
elastic fibers branching at acute angles, in correspondence with the
territories composing a bundle. The elastic basis-substance is

Fig. 59.— Tendon of Achilles in a Longitudinal Section. Stained
WITH Chloride of Gold.

1-8 are tlic bundles, between wliich the interfascicular .spaces are .seen ; T, torn bundles
exhibiting isdlated flbrilla;. Magnified 100 diameters.

marked by yellow color and high degree of luster ; it increases
in amount with the age of the individual.

The sclerotic shows bundles and groups of bimdles, interlac-
ing usually at right angles. In transversely cut groups we see
that the single bundles are separated from their neighbors by a
cement-substance, which, on account of its lower degree of den-
sity, refracts the light less than the basis-substance of the bundles
themselves. The groups of bundles are separated by a continuous
layer of bioplasson, which therefore exhibits a reticular arrange-
ment. In specimens from the sclerotic of dark-colored cattle
this bioplasson layer is very prominent, owing to the presence
of black pigment granules. (See Fig. 58.)

fcj Dense Connective Tissue composed of Coarse Bundles run-
ning in a Longitudinal Direction. The principal representative of
this varietv is the tendon.

CONNECT I Vl<: TISSUE.

Kif)

In thin sections from a fresh ten(h)n, or a tendon prescirved in
(•hroniic acid solution, either stained with chhmde of ^old or not,
we rcco«;nize with h)wer ]>owersof the niicroscopc tliat tlie ti-ndon
is made up of buncUes of a finely sti-iated tissue. All bundles
are spindle-shaped, and vary greatly in size ; they are separated
from each other by lii'lit interstices, in whi<^h, {)articularly in the
injected specimens, the blood-vessels ai'e seen to course aloug and
around the l)undles. The appearance of a bundle is striated as
lon^as the eontinuitj^ of the tissue is unbroken. But where the

Fig. 60. — Tendon of Achilles of a Young Person. Longitudinal
Section. Chromic Acid Specimen.

B, bimdles of striated coiinuctive tissue, liere aud tliere finely dotted; TC, tendon
coi'puscles within the bundles or between the smallest bundles ; IT, interstitial medul-
lary tissiie can-ying capillary blood-vessels, C. Magnified 500 diameters.

razor has torn the bundle, isolated fibrillas appear, which, owing
to their elasticity, retract and (airl. (See Fig. 59.)

Higher amplifications reveal that the larger bundles divide
into a number of smaller ones, all of which exhibit a spindle
shape, and in correspondence with the boundary lines of the sec-
ondary bundles we see spindle-shaped plastids, either single or
in rows or chains, and either nucleated, and, as a rule, pale
granular, or reduced to the size of homogeneous or granular
nuclei. All of these are included under the term " tendon
corpuscles." In advanced age the apparently isolated nuclei
prevail, especially in the middle of the tendon, while in younger

166 CONNECTIVE TISSUE.

individuals, and at the periphery of the bundles at any age, the
rows and chains are more nunierous. The interstices between
the larger bundles contain, besides a few capillary blood-vessels,
a large number of nucleated plastids, either isolated or united in
a continuous layer. The sum total of these plastids, together
with a slight amount of basis-substance, constitutes what we
have called (see page 147) medullary tissue. In advanced age
the medullary corpuscles are much less numerous, and a loose
fibrous connective tissue carries the blood-vessels. Elastic fibers
are, as a rule, not present at the borders of the bundles. A
comparison between the plastids within and those between the
bundles shows them to be alike in size and general appearance,
with the only difference that those within the bundles are rela-
tively few in number, while those in the interstices are very
numerous. The view can, therefore, be maintained that between
the larger bundles there are numerous, and between the small
fasciculi, composing one bundle, there are few, plastids — a view
which, as I shall later on demonstrate, proves useful for under-
standing the structure of the tendon as well as its development.
(See Fig. 60.)

In the transverse section of a tendon we notice fields of basis-
substance very finely dotted, the dots being the transverse sec-
tions of the fibriUae. In the bundles we recognize the gi'anular,
usually nucleated, plastids or tendon corpuscles, with numerous
stellate offshoots, the '' wings " of authors. Offshoots connect
the plastids with each other and with the medullary tissue, or
the loose fibrous connective tissue, present in the interfascicular
spaces. The smaller bundles do not usually show distinctly
marked outlines, as neighboring bundles frequently coalesce, and
are not separated by offshoots of the tendon corpuscles. When
we recall the spindle shape of each bundle, we can readily under-
stand why their sizes vary in transverse section. We may call
a bundle a field which is completely surrounded by interfascicular
tissue, and contains in its center a branching plastid, or, we may
say, a larger bundle is composed of a number of smaller ones,
though not distinctly separated, between which lie the branching
plastids. The blood-vessels are met with only in the interfas-
cicular spaces, running both in transverse and longitudinal direc-
tions ; they penetrate the tendon through the tenaculum, which
connects it with its sheath, and the elongations of which con-
stitute the interstitial formations between the tendon bundles.
(See Fig. 61.)

coxyj'ji Ti \ K nss ue.

107

In oUl aiiiinals, the loose interfascicular connective tisHue is sometimes
fomul freely supplietl with elastic fibers. As Treitz and Koliiker have shown,
the tendons attached to smooth muscle bundles are composed mainly of elas-
tic fibers. L. Kanvier discovered at the periphery of the Itundles of tendon
flat "c(>ll-plates," aiTauf^ed in rows, »>xhil)itinfj elastic ridj^es, either single or
in numbers up to five. His method of examination of tendon is teasing and
l)ulling, and he pulled from ])reference rats' tails, in order to obtain the broken,
fringy ends of the delicate tendons along the vertebral column. After he had
pulled and severed tlie tendons, he transferred the fringe to the glass slide,
and, in order to prevent it from shrinking, sealed it at both ends to the slide.
Although this method is not very inviting, pulling rat-tails became quite fash-
ionable in the laboratories in Europe a numl)er of years ago. Kamier denies
the existence of cell-formations in the tendon other than the endothelial
plates. Perhaps these are flat, endothelial investments of the larger bundles

Fig. 61.-

MisitatCtN.T.

-Tendon of Achilles of a Young Person.
Section. Chromic Acid Specimen.

Transverse

B, bundles fiuely dottetl ; C, tendoncorimsclt' with offshoots, connecting with the inter-
fascicular tissue, IT; the latter contains the capillary blood-vessels, BV. Magnifleil 500
diameters.

similar to the investing sheath of Boll, unquestionably present around the
periphery of the tendon. Liiwe has maintained that such an investment is
also found around the bimdles of the tendon, but he has been contradicted
by other observers. The elastic ridges are probably the place of attachment
of neighboring bundles.

One of the greatest difficulties encountered by former observ-
ers was to explain satisfactorily the wing-like offshoots of the

168 CONNECTIVE TISSUE.

tendon corpuscles seen in transverse sections, as no trace of such
formations is visible in longitudinal sections. This difficulty was
overcome by the discovery of offshoots of the tendon corpuscles,
brought into view in longitudinal sections by the silver and
gold staining. The minutest features in the structure of the
tendon are described on page 122, and illustrated in Fig. 37 and
Fig. 38.

The articular ligaments are formations closely allied to ten-
don ; between their bundles, however, a greater amount of loose
connective tissue is found than in the tendon.

fdj Dense Connective Tissue composed of Interlacing Ribbons.
This variety is essentially constructed in the same manner as
tendons, but instead of spindle-shaped bundles, we find flat, rhom-
boidal ribbons. Periosteum is representative of this tissue, a
description of which is given on page 125. The elastic fibers bor-
der each ribbon or subdivide it into smaller rhomboidal fields, a
feature which is explicable by the history of development of the
territories of the ribbons.

In the dura mater and the pericardium, the bundles are dis-
tinctly striated and not quite so flat as those in the periosteum.

In aponeuroses, the bundles, in ac^cordance with the general
sheet-like form of this tissue, are flattened and interlaced, chiefly
in a rectangular direction. The interstices between the bundles
are quite narrow, but plastids are observed here as well as in the
tendon. C. Ludwig, who forced colored liquids into these inter-
fascicular spaces, mistook the beautiful rectangular reticulum
thus obtained for lymph-spaces. Formations kindred to apon-
euroses are the fasciae and the tendinous capsides of different
glandular organs — f. i., the capsule of the kidney, the albuginea
of the testis, the sheath of the cavernous bodies of the penis, etc.

In some ligamentous formations, such as the Lig. sub-flava of
the vertebrae, the Lig. nuchee, the membr. thyro-cricoidea, the
Lig. stylo-hyoideum, etc., the fibrous basis-substance is almost
completely transformed and condensed into the yeUow, elastic
substance which appears in the form of branching reticidar
fibrillae, between which are scantily found bundles of striated
connective tissue.

fej Coalesced Layers of Elastic Basis-substance, arranged in a
sheet-like manner, are often found at the borders of connective-
tissue formations, close beneath epithelial and endothelial layers.
They bear the names of hyaline, structureless, or basement mem-
branes, in contradistinction to "cuticular formations" of a similar

CONNECTIVE TISSUE. l(i<)

appoaraiU'O fouTul between epithelial layers — f. i., between tin-
root-sheaths of the hair.

Elastic membranes certainly are not strnetureless, bnt exhibit
a reticulum of living; matter of extreme delicacy, concealed in
the fresh condition by the liifi^hly refracting elastic basis-substance.
I am positive that such a retienlum is present in Bowman's and
Descemet's layers of the cornea. By means of this reticulum, the
connective tissue is held in living union with the epithelium.
Such membraneous formations may vary greatly in width, even in
the same tissue, — f. i., the cornea, — and sometimes they may be
entiri'ly al)sent. They, when present, resist the action of acids
and alkalies, and, to some extent, the inflammatory process.

Elastic membranes of the connective-tissue series are the fol-
lowing : Bowman's layer at the outer and Descemet's layer at
the inner surface of the cornea; the capsule of the crystalline
lens and the hyaloid membrane of the vitreous body ; the layer
between the outer root-sheath and the follicle of the hair ; the
elastic layer beneath the endothelial coat of larger arteries ; and
the investing, sometimes fenestrated, layers beneath epithelia of
glands — f. i., the Siilivary, the mammary glands. In the Iddneys,
the connective tissue of the capsule of the tuft, also that which
lies between the tubular formations, contains a large amount of
elastic substance, which produces a very firm support for the
epithelia.

The striated muscle-fibers, with the exception of those of the
heart, are invested by an elastic membrane, termed sarcolemma ;
so are the medvdlated nerves around the axis-cylinder and around
the myeline — /. e., axis-cylinder sheath and myeline sheath.

ffj LameJlated Layers of Fibrous Interlacing Connective Tissue.
The only representative of this variety is the cornea of the eyeball,
the basis-substance of which, although morphologically closely
allied to that of elastic sulistanee, is chemically different from
both " elastine" and '' chondrine." A. Rollett (1859) proved that
the "amorphous" basis-substance of former histologists consists
of bundles of connective tissue, which are connected by a kind
of cement-substance soluble in lime-water and in l)aryta-Avater.
The main feature of the cornea is that the bundles join to form
■very thin flat layers, the lameUaB ; while these lamellae them-
selves are connected by somewhat looser bundles, traversing the
less condensed interstices between them.

In the fresh cornea no trace of plastids (cornea corpuscles) is
visible ; but if the cornea be kept in an indifferent liquid, after a

170

CONNECTIVE TISSUE.

while faint traces of these corpuscles become perceptible, exhibit-
ing a few scanty offshoots. The shape of these corpuscles varies
greatly in different portions of the cornea, as well as in the cor-
nea of different animals.

A clear idea of the nature of the cornea corpuscles can be
obtained only by resorting to re-agents. Von Recklinghausen
(1862) first l)rought to view the lieautiful light and l)ranching
spaces in a dark basis-sul)stance by applying nitrate of silver.
He considered them as lymph-spaces or juice-canals, supposing
them to be the beginnings of the lymphatics proper. In these
spaces, he thought, the "cornea-cells" were suspended. (See
Fig. 62 ~

Fig. 62. — Lamella of the Cornea of a Grown Cat, Stained
WITH Nitrate op Silver.

S, light 1)iaucliing 8i)aces with serrated edges, traversing the dark brown granular
basis-siihstauce. B, F, fibers connecting the lamellie and torn by the process of splitting the
laniellie. Magnified 500 diameters.

Later researches have shown that the "lymph-spaces" of the
cornea are closely related to the cornea-cells, which were mean-
while demonstrated by W. Kuehne (1864) and others to be-
composed of contractile protoplasm, and endowed with properties
of life. The method of gold-staining has proved to be the most
valuable for revealing the structure of the cornea corpuscles and
their relation to the basis-substance. (See Fig. 63.)

coNNEVTi I ■;•; Tissi'j':.

171

Researches on ttik Microscopical Structure oe the Cornea.
By WiLMAM Hassloch, op New York.*

It is generally acknowledged that the substantia jn'opria of the cornea is
made up of fibrils united into fascicles ; that the majority of those Vjundles,
by being more or less parallel to the surface of the cornea, form the lami-
nated structure of the latter, at the same time crossing one another, and so
giving rise to a kind of lattice-work; while other fibers and bundles traverse
the cornea in various directions. The fibrils, as well as the fascicles and
lamella?, are connected with one anotlier by an intermediate cement-sub-
stance, which somewhat differs from the fibrils in its chemical reaction.

A-

UassCNECeiN.Y.

Fig. 63.— Lamella op the Cornea of a Grown Cat, Stained with
Chloride op Gold, after Previous Treatment with Dilute Lac-
tic Acid.

C, dark rtolet nucleated cornea corpuscles, traversiuf; the pale violet granular basis-
substance, B. JV, nerve-tibrilUE, counectinf; with cornea corpuscles. Magnilled r)00
diameters.

But, concerning the relation of the protoplasm to the basis-substance,
observers are of very different opinions. Some of them do not admit the
existence of the protoplasmic bodies at all, asserting that within the basis-
substance of the cornea only a tubular system is present, lined with " cell-
plates." Other histologists hold the view that there is a certain quantity of
protoplasm (cells of the cornea) inclosed in the "serous spaces," in which it
ramifies, but which it does not completely fill. One of the most prominent
advocates of the latter opinion is W. Waldeyer,t deriving his views chiefly

*• " Archives of Oplitlialmology and Otology," vol. vii., 1878.
t Article "Cornea," in Graefe-Saeniisch's Hand-book, 1874.

172

CONNECTIVE TISSUE.

from the results of injeetions made by him and other recent observers into
the tissue of the cornea. Fhiids, pressed into the corneal parenchyma,
produce, indeed, ramified figures resembling the " corneal corpuscles." W.
Kuehne, S. Strieker, and A. EoUett state that there are complete corneal
cells with protoplasmic bodies, with nuclei and nucleoli, within the ramifying
spaces, and that they fill these spaces completely. W. Engelmann denies the
existence of preformed spaces inclosing corneal cells, etc. He states that
there are spaces containing nothing but protoplasm, and this is, in my ojjinion,
the only correct view, as I shall endeavor to prove.

In order to study the relation of the protoplasm to the basis-substance, I
chose the cornea of the dog and of the cat, giving preference, after repeated
trials, to that of the cat, as has previously been done by S. Strieker, on
accoimt of its easy splitting. With some practice one may succeed in obtain-
ing lamellfe which present two or even only one layer of corneal corpus-
cles, and which, therefore, are suflBciently transparent to admit of being
examined even with the highest powers of the mierosenpc.

Fig. 64. — Lamella of Cornea of a Cat, Aged One Year and a Half,
Stained with a Two per cent. Solution of Nitrate op Silver.
Two Layers. [Published in 1878.]

S, light fields with p.ile granular contents, faintly marked nuclei, and coarse and fine
livocesses. Every light field has perforated borders, and thus abundantly communicates
with a delicate light net-work which traverses the dark brown basis-substance, H, in all
directions. Magnified 1000 diameters.

To stain the cornea, I at first tried nitrate of silver. The cornea of a eat
was taken out immediately after death, and was put into a two per cent,
solution of nitrate of silver for one-half to one hom-; then it was washed with
distilled water, and, finally, for several days left under the influence of a very
mild dilution of acetic acid. Instead of the acetic acid, in later experiments,
I substituted lactic acid, which proved even more satisfactory than the
former. After being prepared in this way, the cornea of tlie eat was ready

CONNECTIVE TISSUE.

173

to be split into liiiiit'Uu'. The siicciiiiciis were iiioiiiitcd witli ('(iiiiil piii'ts of
glyccriiic iind water.

Witli ciilur^jeiiu'iits of ;{()()-;■")()() sucii linncllii' show in ii dark j^round —
basis-sul)staiif(> — li^dit fields witli numerous connect inj; hraneiies, K*'i'<'rally
known as Von Kccklinghausen's serous caiuiliculi ; and even an enlarf^enient
of 500 is sufficient to prove tliat the outlines of these light spaces do not
appear smooth at all, but granular — viz., abundantly perforated, and that
the brown or gray-brown looking basis-substance is finely granular.

With higher powers (immersion lenses, with enlargements of 8(»0-1200)
the following facts are observed : Within the light spaces oblong nuclei, with
very faint contours and a gi-eat number of extremely pale gi-anules, are visible.
The light s{)aces are connected with their neighbors by light processes of
various sizes, traversing the basis-substance. The borders of these light
fields and their branches are abundantly perforated, like a sieve, throughout,
so that true outlines do not exist. Fine, light tracts run from every light
space and its braiu-hes through the basis-substance, profusely ramifying and
anastomosing, sometimes radiating, and thus forming an extremely delicate
light net-work, the threads of which traverse the basis-substance in all
directions, and connect with the light fields and their processes at the whole
circumference. What with lower power was recognized as granular struct-
ure is by higher enlargements elucidated as a very fine light net-work, the
meshes of which are filled by the dark brown basis-substance. (See Fig. 64.)

Fig. 65.— Cornka of a Cat, Two Years Old, Stained with Nitrate
OF Silver. TRAxs^^;RSE Section. [Published in IS 78.]

.S', liglit fields cout.ainiu!? fine pale granules, with coarse and fine lijjbt oft'slioots. iV, nerve-
fibers in conn('<>tion with the light reticulum, which traverses the dark brown basis-sub-
stance, Ji, throughout. Magnified 1000 diameters.

On thin transverse sections the silver-stained cornea of the eat shows the
same ramifying light fields as in split preparations, with the only difference
that their vertical diameters are notably smaller, while their horizontal diam-
etersare the same as those of the light fields of the lamella?. The light spaces
branch out in all directions, so that not only the light fields of the same
stratum are connected with each other, but even those of different layers
anastomose by ascending and descending — more or less oblique — processes.
Besides these ramifications, especially in the outer strata of the cornea, some
fine straight light lines are met with, which, for reasons given below, are
proved to be nerve-fibers. On transverse sections, also, the bro\\Ti basis-
substance is traversed by light ramifying tracts, to such an extent that the

174

CONNECTIVE TISSUE.

cement-substance cannot be distinguished from the other components of the
cornea. (See Fig. 65.)

Furtlier, I tried to stain the cornea of the dog affd of the cat with chloride
of gold. Many experiments failed, though I had exposed the cornea to the
influence of the chloride of gold for hours. The after-treatment with acetic
and tartaric acid gave only negative results. I could never see distinct
cornea corpuscles with their ramifications until, at last, by the aid of lactic
acid, I succeeded in obtaining specimens of such beauty and clearness, that
all doubt with regard to the finest structure of the cornea disappeared.

My method is the following : The cornea of a cat is taken out immediately
after death, soaked in a ten per cent, solution of lactic acid for a period of
about twelve hours ; then diu'ing one or two hours it is kept in a one-half per
cent, solution of chloride of gold, slightly acidulated by the addition of a few
di'ops of lactic acid, and finally exposed to the influence of daylight. The
superficial strata of the cornea and a peripheral border of one mm. tiu'u yellow,

[W v^/x.^^

Fig. 66. — Lamella of the Cornea of a Cat, Two Yeaks Old, Soaked
IN Diluted Lactic Acid and then Stained with a One-half per
cent. Solution op Chloride op Gold. [Published in 1878.]

P, (lark violet fields, the cornea cori)U8cles, the nuclei of whicli are mostly hidden, with
offshoots of different sizes. The cornea corpuscles and their oftslioots are connected with a
dark violet net-woi-k traversing tlio pale violet basis-substance Ji ,- the latternet-woi-k shows
broader meshes than that of the corpuscles and tlieir branches. Magiiilied lOOO diameters.

and are of no use for examination, but the other part, the characteristic
purplish tint of which shines through the yellow envelope, is invaluable for
research. After having made the above described experiments, I learned
that F. S. W. Arnold, of New York, had previously used lactic acid for
the reduction of chloride of gold ; but he informed me that his method differs
from mine, inasmuch as he uses the chloride of gold in the first stage of the
preparation, followed by the lactic acid — just the reverse of my plan of
treatment.

CONNECTIVE TISSUE.

17.')

The conu'ii of tlu> cat, jn'cpiircd iil'tcr my inctlidd, si>lits rciidily, ami its
laintllti', aft IT turnini; dark ciioii^di by tlio iiiilueiice of dayli^lit, Jii)in'ar under
tlu> inic'roscoi)o throughout their wliolo extent strewn over witli numerous,
ri(dily ramifying, dark violet corpuscles. In many of the latter the nuclei are
•listinctly visible; the corpuscles themselves crowded with dark granules ; the
basis-substance light, pale violet, and also having a granular appearance. I
have searched through a great many lamella?, but I have never found any
corpuscles that did not shoot off into branches ; everywhere and always I met
with only ramifying, dark violet corpuscles, with numerous connections and
in different strata of varying sizes. The dark violet fields fully coincide with
the light spaces of the silver-stained cornea as to size, figure, and connections,
as has been stated by W. Kuehne. Tlie only difference is that in the silver

Fig. 67. — Lamella of the Cornea of a Cat, Two Years Old, Stained
WITH A One-half per cent. Solution of Chloride of Gold, after
HAVING been Soaked with Diluted Lactic Acid. [Published in 1878.]

P, dark violet fields, the nornea corpuscles, witli onlj-a few broad offshoots, but numerous
dark violet, tliread-like connections, non-mcdullated nerve-fibers, N, the latter partly travers-
ing the cornea cori)U8cles and partly joinin.ff the net-work of the same ; between the cornea
coriniscles and the net- work of tlie basis-substance, B, extremelj' fine retiform connections
are present ; the latter net-work also connects with delicate nerve fibrilla", H. Magnified
1000 diameters.

specimen light fields are visible in a dark ground, while in the gold specimen
the dark corpuscles appear in a light ground — pictru-es which correspond
with each other as the negative with the positive photograph.

Gold specimens examined with high powers (800-1200) show that the
dark violet ramifying corpuscles, without exception, have a retiform structure,
and that the nucleoli, the contoui-s of the nuclei, and all the granules are con-
nected with one another bv innumerable line threads. The whole net-work

176

CONNECTIVE TISSUE.

is tinted equally dark violet, while its extremely naiTow meshes appear pale
violet. (See Fig. OG.)

The borders of the corjiuscles and their branches are nowhere distinct;
contours in the real sense of the word are wanting in the gold specimen as
well as in the silver specimen, inasmuch as from the whole circiimference of
these ramifying, dark violet fields immense numbers of fine threads protrude,
to join their neighboring dark violet granules within the basis-substance. The
examination of any portion of such a specimen will not fail to convince the
observer that also in the basis-substance nearly all dark granules are inter-
connected by fine threads. The cause of the difference between the shade of
the cornea corpuscles and that of the basis-substance is, that in the former the
granules are larger and lie close together, and consequently the meshes are
very small, while within the basis-substance the granules are mostly fine and
more dispersed, and for this reason are separated fi'om one another by larger
meshes.

In some lamellae, and, as it seemed to me, principally in the outer layers
of the cornea, many corpuscles are connected with one another, not by broad
branches, but by dark violet, more or less straight lines, which, for their
characteristic rosary-like structure must be considered non-medullated nerve-
fibers. (See Fig. 67.)

In profile, the gold-stained cornea of the cat offers another proof of the
coincidence of the positive gold image with the negative silver specimen.

Fig. 68. — Cornea of a Cat, Two Years Old, Stained with a One-
half PER CENT. Solution op Chloride of Gold, after being
Treated with Diluted Lactic Acid. Transverse Section. [Pub-
lished IN 1878.]

P, dark violet fields with broad brandies and with fine off'slioots, tlie latter beinj^ nerves,
N ; the net- work of the dark fields every wliere Is in connection with tliat of tlie basis-sub-
stance, B. Magnified 1000 diameters.

Flat, elongated, dark violet bodies are visible, which, in the horizontal direc-
tion, anastomose with one another by means of fine long processes ; while
broad, rather oblique, dark violet branches ascend and descend to connect
the corpuscles of different layers. The net-work of the dark fields and that
of the basis-substance are shown with the same clearness as in split speci-
mens. The laminate structure of the cornea is just as imperceptible in these
transverse sections as it is in those of the silver-stained cornea. (See Fig. 68. )
In transverse sections of the gold-stained cornea of a dog I observed, espe-
cially in the central parts of the cornea, formations which sufficiently explain

CONNECTIVK TISSl'K. 177

the views ol" W. WuliloyiT, wlio iiiiiiiitjiiiis tliat the cornoii corpuscli'S do not
c'oiiipletoly fill the " serous spiicos." There I saw groups of cornea corpuscles
which leaiuMl mainly against one of the walls of the space, while a more
or less considerable portion of the latter appeared empty. A closer exam-
ination, however, proved that these apparent voids are artificial products,
naTuely, vacuoles. It can be observed that the eccentric cavity is situated
within the cornea corpuscle, and on its whole circumference is inclosed by the
jirotoplasni of the cornea cor|>uscle. No matter how thin the strip of pro-
toplasm which is interposed between the vacuole and the periphery of the
" serous space " nniy be, it is always present. It is known that such vacuoles
can arise from contraction of the living matter within the protoplasm. The
cpiestion why these contractions, perliaps as a result of the action of the
chloride of gold, were observed only in certain groups of cornea corpuscles,
remains unsolved. In the cornea of the cat I have never met w'ith any forma-
tions of this kind.

From these observations it clearly follows that a tiihidnr system, <is
described Iii/ J'on lieckliiu/haiisen, docs not exist in the cornea at all. The light
fields which the silver specimens of the cornea show are not " serous
spaces," but protoplasmic bodies, as stated by W. Engelmann and others, viz.,
spaces which are wholly filled with protoplasm. The strongest proof of this
assertion is found in the result of the method of staining the cornea with
chloride of gold, improved by the treatment with lactic acid, as it exhibits the
cornea corpuscles in perfectly clear images, which in every particular corre-
spond to the negative silver images. Whether an interstice filled with fluid
remains between the wall of the so-called serous space and the protoplasmic
body or not, I will not yet venture to decide ; but as the protoplasm itself
contains a considerable amoimt of fluid, it is not necessary to admit the pres-
ence of peripheral cavities tilled with serum. Wherever an interspace between
a cornea corpuscle and the wall of the "serous space" can be observed, its
presence depends upon the formation of a vacuole, and cannot, therefore, be
maintained in opposition to my view. Nor do the parenchymatous injections
prove anything contrary to it, for it is apparent that colored fluids, which
are forced into the protoplasmic spaces, will press the soft protoplasmic
bodies against the walls of such spaces, and thus assume the principal forms
of the latter.

My observations further show that the protoplasm of the cornea cor-
puscles has a retiforra structure, which can be demonstrated by the above-
described method of staining the cornea with chloride of gold. The question
whether or not this reticulum be an artefact should no longer be a matter of
dispute, since in the creeping amoeba, in colorless blood-corpuscles, and in
pus-corpuscles the same net-work has been demonstrated, and by photogra-
phy made visible even to the naked eye. That this net-work (nucleoli, bor-
dering layer of the nucleus, granules, and connecting threads) is the li^'ing
matter, the meshes of which inclose the lifeless protoplasmic fluid, is proved
as well by the reaction of the chloride of gold, as also by the appearances
observed in inflammation, which S. Strieker has so carefully studied and
illustrated.

Finally, my observations show that the living matter thoroughly traverses
the fibrous basis-substance of the cornea in the form of an exquisitely deli-
cate net-work, the existence of which is proved beyond all doubt by the
correspondence of the negative silver with the positive gold specimens,
12

178

CONNECTIVE TISSUE.

though in the fresh condition of the cornea it is as imperceptible as are the
cornea corpuscles themselves. K wandering bodies exist within the normal
cornea, — I have never met with them, — such bodies will find their paths only
in the cement-substance, never within the lamellae. As the lamellae are con-
nected with each other by innumerable fine threads of living matter, which

?g-S

^^-

-^—B

Fig. 69. Periosteum of the Femur of a New-born Pup. Transverse

Section. [Published ix 1873.]

F. striated tissue of periosteum ; S, spintUe-shapert plasties in tbe formation of a striated
basis substance ; Jtf, mednllary tissue between the periosteum and tlie bone; O, medullary
corpuscles in the formation of bone-tissue ; B, fully developed bone-tissue. Chromic acid
specimen. Magnified 800 diameters.

penetrate the cement-substance, — not taking into consideration the connect-
ing broad, oblique bundles of fibers,— the reason why such wandering bodies
move in zigzag lines is readily comprehended.

As for the finer structure of the cornea, I fully agree with C. Heitzmann's
\iews regarding the connective tissue in general. The living connection of

COXXECTT J 7'; TISSUE. 1 7!)

the protdplasmic bodios, wliicli this ohserver has discovered in the myxoina-
tous and (ilirons connective tissue, as well as in that of the cartilage and
hone, lias bt-en successfnlly demonstrated by ine in the cornea also. The
liviiij; matter presents in connective tissne two different net-works : a narrow
one, the meshes of which are tilled with tluid, — protoplasm, — and another
with broader meshes, traversing the basis-substance.

Development of Fibrous Connective Tissue. This article is a
translation of a pnblication which I made in 1873.* I have
notliinfj to add to the oonelnsions drawn at that time, bnt shall
make the explanation of the observations a little more detailed.

Fig. 70. — Periosteum of the Femur of a New-born Pup. Longitu-
dinal Section. Chromic Acid Specimen, Slightly Stained with
Chloride of Gold. [Published in 1873.]

M, layer of medullary corpuscles ; I, layer of corpuscles iu the stage of indifference, pre-
ceding the formation of basis-substauce ; C and Ci, spindles of basis-substance of tibrous
connective tissue ; E, elastic ledge. Magnified 800 diameters.

In transverse sections of a shaft-bone of a newl}^ born pup, we
recoo:nize between the striated periosteum and the bone-tissue a
broad layer of medullary tissue, into which project a few striated
bundles of the periosteum proper.t (See Fig. 69.)

* " Untersuchungen iiber das Protoplasma. IV. Die Entwickelung der
Beinhaut, des Knochens und des Knorpels." Sitzungsber. der Kais. Akad.
der Wissenschaften in Wien. July, 1S73.

t Th. Billroth ("Archiv f. Klin. Chirurgie," Bd. vi.) termed this layer
"cambium." A. Rollett ("Manual of Histology," by S. Strieker) illustrates
it in a transverse section of the fore-arm bone of a human embryo, five
months old.

180 CONNECTIVE TISSUE.

In lon^tudinal sections from the surface of a shaft-bone of
the same animal, we see in the periosteal tissue different forma-
tions corresponding to the stages of deveh)pment of protoplasma.
Between longitudinal bundles of narrow, bright ribbons we
recognize fields of corpuscles like those of the medullary tissue,
or chains of such corpuscles with distinct vesicular nuclei. Fur-
thermore, we see fields of flat, spindle-shaped protoplasmic bodies
of greatly var\dng size, and with either indistinct nuclei or none.
There are fields composed of flat, rhomboidal protoplasmic
bodies, some of which exhibit formations like nucleoli. We also
meet with fields, the rhomboidal bodies of which appear homo-
geneous, and slightly shining. Lastly, we encounter ribbons
and ledges, composed of very much elongated rhombs, character-
ized by a peculiar yello^^'ish color and a considerable luster. The
slightly shining fields are the connective-tissue ribbons proper of
the periosteum ; while the highly refracting ribbons and ledges
are termed elastic. (See Fig. 70.)

The examination of good chromic acid specimens, better still
such specimens slightly stained with chloride of gold, convinces
us that each larger field is separated from the neighboring fields,
and within the fields each gi-auular or homogeneous corpuscle from
the neighboring corpuscles, by a narrow light rim, which is invari-
ably traversed by delicate grayish spokes. Even in the narrow
elastic ribbons a faint transverse striation is here and there seen.

In such a specimen, deeply gold-stained, the differentiation of
fields and ribbons disappears, and there become visible at certain
intervals spindle-shaped, dark violet bodies, coiTcsponding to the
protoplasmic bodies, while the rest of the tissue is split up into a
reticulum, with either fine or coarse gi-anules as nodular points.

The periosteal tissue is composed of narrow, spindle-shaped
fields, wherever it exhibits a striated or fibrous appearance. In
portions made up of broad ribbons, on the contrary, each field
represents an elongated rhomb, in which lie, at pretty regular
intervals, oblong, flat, nucleated protoplasmic bodies (the '' peri-
osteum ceUs")- Between the rhombs are narrow, bright ledges,
the elastic fibers, which either connect several rhomlis into large
})undles, or subdivide a single rhomb into smaller rhomboidal
fields of varjnng size. At the corners of the rhombs the elastic
fibers are interconnected with acute angles.

If, owing to a laceration of the tissue with the razor, a
broader, slightly shining ribbon projects from the border of the
specimen, we often see at its edge, either on one side or on

connective: Tissrh'. ihi

l>()tli, u very bri^lit strij) ilcniarcatiii^ the rihljon Itoni ii(lja(;(;nt
{)r()t(»})ljisnuc bodies.

In tlie periosteal tissue of a new-l»oi-ii iiiip, tlierefore, we are
enabled to traee the transitions of different forms of medul-
lary elements into sometimes narrow, sometimes broad and flat,
spindle-shaped ])r(>t<)i)lasiiii(' bodies. We beeonie eonvineed that
by a gradual change of the latter arise both the '* connective tis-
sue" and the "elastic fibers."

The development of the connective tissue in general is a much
tlisputed, and to this day unsolved, cpiestion.

In looking over the vast literaturo on this subject, we may sura up all the
views of prominent observers into two theories. One of these may be termed
the nccrctioii theory ; it implies that the intercellular- or basis-substance is i)ro-
duced by a sort of secretion of the cells from an originally homogeneous mass
between the cells. The other, which may be styled the transformation
thcorif, maintains that the cells themselves are transformed into basis-sub-
stance, either by a process of splitting in their entirety, or by a process of
transformation of the cell-protoplasm at its peripheral portions.

Secretion Theory. Henle * was the first to assert that an originally homogene-
ous substance splits into tibrilla? and bundles of fibrilla?. According to Reichert,
the homogeneous substance proceeds from a fusion of the cell-membranes with
an intercellular substance, and the fibrilhe are only the optical expression of the
foldings of this substance. The fusiform cells present in embryonal connect-
ive tissue, according to Virchow, Donders, Gerlach, and Kcilliker, do not
share in the formation of fibers, but persist, as Virchow expressed it, as cells,
or are convei-ted into a plasmatic canal-system. The last-named observer is
the originator of the idea that the intercellular-substance is a product of
secretion of the cells, and this \T.ew prevailed for quite a time. Among the
recent observers, A. RoUett, L. Ranvier, and I. Kollmann advocate the modi-
fied theory that fibrous basis-substance may, to a certain extent at least, orig-
inate independently of cells.

Transformation Theory. Th. Schwann t first maintained that the cells, after
being elongated, split into bundles. After Max Schultze's discoveries concern-
ing the protoplasma, \ the theory of Schwann was modified. Max Schultze held
that the fibrous basis-substance of connective tissue arises from a coalescence
of embryonal cells composed of protoplasm, and destitute of an investing mem-
brane, and that a thin layer of unchanged protoplasm remains around the
nucleus of the primary cell representing the connective-tissue cell. Lionel
Beale, in England, ^ independently of the German observers, expressed sim-
ilar views ; he claimed that the connective tissue is originally made up of
elementary parts, consisting of germinal matter, and that subsequently a
part of the germinal matter is converted into formed material. According to
these views, the originally living protoplasm is, by chemical and morpho-
logical changes, transformed into the lifeless basis-substance, though the cen-

* "Allgeraeine Anatomie." Canstatt's Jahresbericlit, 1845.

t " Mikroskopischf Uutersucliuiiffeu," etc. Ui-rliii, 1839.

X Reiclieit auil Du Bois Keyruoud's Arcliiv. 1861.

{"The Structure of the Simple Tissues of the Human Body." 1860.

182 CONNECTIVE TISSUE.

tral portion of the cell may remaiu unchanged protoplasm. This theory was
adopted, with more or less modification, by E. Briicke, Yv&wz Boll, Waldeyer,
and otheii?. Briicke's pupils corroborated the onginal view of Schwann — viz. :
that the fibers of connective tissue originate directly from offshoots of the
cells.

Elastic Substance. The elastic fibers, first discovered by Donders,* were
thought to be by this observer the product of embryonal fu.siform cells which
have passed through transitional forms into a plexus of elastic fibers. This
view was confirmed, with certain changes adapted to the protoplasma theory,
by F. Boll and A. Spina.

Territories. An important discovery concerning the structm-e of the basis-
substance was made by Fiirstenbergt — xaz. : that certain chemical re-agents
may break up the basis-substance of cartUage into globular or polyg-
onal fields, inclosing the central cell. He took these fields, the " territo-
ries," for products of secretion of the cells. VirchowJ con-oborated this
discovery, and based very important biological views upon theii- presence
(see page 136). He considered the central cell the queen of the territory, and
all changes of the latter as depending upon the changes of the cell. R. Hei-
denhain (\ also made noteworthy researches as to the territories of the hyaline
cartilage.

I have stated on a previous occasion (see page 132) that the
territories, which are traceable in all higher developed varieties
of connective tissue, are the true units of this tissue ; so that
anybody who understands the development of a single territory'
understands that of connective tissue /;/ toto.

From what I have described as to the basis-substance of the
earliest formation, — viz. : the myxomatous basis-substance of
medullary tissue (see page 118, Fig. 33 and Fig. 34, and page 147,
Fig. 47), — it is obvious that I essentially agree ^vith those observ-
ers who have maintained a direct transformation of the proto-
plasm into basis-substance. I assert, in entire accord with Max
Schultze and Lionel Beale, that every territory originates from
coalescence of prot<jplasmic bodies — plastids.

If we recall the fact (see page 133) that the basis-substance of
a number of tissues is traversed by a delicate reticulum of living
matter, we can realize that in the process of the formation of a
tissue no living matter, certainly not all of it, perishes, Ijut that
it merely becomes in\dsible in the portions infiltrated with basis-
substance.

If we, furthermore, recall the fact (see page 46) that the pro-
toplasma itself goes through phases of develoj)ment, we can also
realize that the living matter appears in vaiyiug groups and

* "Zeitsclirift f. Wissenscliaftliclie Zoologic." Bd. iii.

t "Mullev's Arcliiv." 1857.

t "Cellular I'atliolofne," i. Aufl., 1858.

§ "Stndien des Pliysiolog. Institutes zu Breslau," ii. 1SG3.

CONNECTl VE TISSUE.

183

aceiimulatioiis — viz. : as a cotnpaot lump, as a niiclcatod body
(plasti(l), or Jis a n'ticuliini inlilt rated with basis-substaiict'.

It is not proved that the livinjf portion of j)rotoplasnia is really
ever changed into basis-substance ; I have discovered the living
matter, just as seen in medullary tissue, in places in which the

Fig. 71. — Diagrams op the Development of Connective Tissue.

.V, (liiiftrain of the secretion theory : a, tlie enibrj-onal ceU ; b, the cell enlarged aiitl its
periphery transformed into basis-siihstanee ; c, the cell in middle of the considerably aug-
mented basis-substance. T, diagram of the transformation theory : a, a number of medullary
corpuscles, grouped in the shape of the future territory; i, the perix)lieral portion of proto-
l)lasm transformed into basis-substance ; c, the cell in middle of basis-substance, sprung from
a transformation of tlie iieripheral protoitlasm. Ji, diagram of the bioj)lasson theory: a, a
number of plastids giouped in the shape of the future territorj-, all being reticular in struct-
ure and interconnected ; b, the plastids coalesced, of the peripheral ones only the nuclei left;
c, the formation of basis-substance accomplislied, the central free plastid being the counectlve-
ti.ssue corpuscle, with coarse and delicate offshoots into the basis-substance.

protoplasm was formerly thought to have perished ; nor is there
any necessity, indeed, to assume that the basis-substance is a
product of the living matter ; for it may just as "well be held
that nofJtiiifj hut the liquid orujinalhi fillimj the meshes of the living
reticulum is transformed into basis-substance.

184 CONNECTIVE TISSUE.

In this ease, we have simply to assume that solution or lique-
faction of an already formed basis-substance sets free the living
matter, and that the new gi-ouping into lumps and elements
(plastids) depends upon the formation of a new basis-substance
in the mesh-spaces. This newly formed basis-substance will look
striated or fibrous if the groups be spindle-shaped, such as in
tendon and young bone-tissue ; it will be ribboned if the groups
be flat plates, such as in periosteum ; it will appear lamellated
should the groups be lenticular bodies, such as in bone-tissue ;
or, lastly, it will become globular with the formation of globular
masses, such as in hyaline cartilage.

Within the basis-suhstance, the reticulum of tiring matter and
the central portion of the protoplasma^ the "cell,'' or " plastid,"
remains intact. From the central corpuscle the reticulum ema-
nates, according to the shape of the unit of the tissue, either in a
prevailing bipolar, or rectangular, or uniformly radiating direc-
tion. The forms of the fields of basis-substance will necessarily
be determined by the main directions in which the li\'ing matter
is distributed. The formation of basis-substance seen in that of
a territory is illustrated in Fig. 71.

In order to elucidate in accord with the new \'iews the forma-
tion of a fibrous basis-substance, we must consider the fact that
one territory may contain several plastids interconnected. If
each of the plastids, including those sharing in the formation of
basis-substance, become elongated and split into delicate spindles,
the result wiU be a large spindle- or rhomb-shaped territory, com-
posed of numerous delicate spindles, which coalesce into fibrillae,
between which remain elongated plastids unchanged. As men-
tioned before (page 158), each fibriUa in reality is composed of
a number of delicate spindles. Between the territories a larger
number of plastids is left, and the blood-vessels take their
coiu-se ; or a more solid fibrous reticulum is developed, inclosing
the territories, as, f. i., in mj^omatous connective tissue.

The gradual development of basis-substance, therefore, admits
of the following analysis :

In mediLllary tissue, a single plastid, or a small number of
such, is converted into myxomatous basis-substance without the
formation of ten-itories ;

In reticular tissue, a single plastid, or a small number of such,
changes into myxomatous basis-substance, the territories of which
are separated by a reticulum of plastids or fibers. The plastids
within the territory remain unchanged in the lymph-tissue ;

CONNECTIVE TISSUE. 185

In the uinLilieid cord, a lar^e numl)er of plastids coalesce
into territories of a partly myxomatous, partly fibrous, basis-
substance, and these territories are sej)arated l)y a broad reticu-
lum of i)lastids, the " stellate mucoid-cells " ;

In fibrous connective tissue, each bundle is the result of
coalescence of plastids much elongated and split uj), and is
composed of one or a nmnber of teiTitories, in which remain the
connective-tissue corpuscles. A large number of plastids is left
between the bundles ;

In tendon, each bundle is a large territory containing a
number of plastids arranged in chains, wHth numerous smaller
bundles between them ;

In periosteum, the plastids have flattened out so as to build up
a rhomboidal ribbon, with a number of unchanged plastids, each
ribbon being composed of one territory or of a number of them ;

In the cornea, the flattened bundles or ribbons have coalesced
into layers, traversed by the cornea corpuscles ; each lamella is a
flattened territory, and between the territories are plastids similar
to those within.

Between the groups, composed of plastids in many instances,
and at an early stage of development, a very dense basis- or cement-
substance appears. This is the " elastic tissue," seen in the
periosteum in the shape of naiTow plates or strips at the borders
of the ribbons and their constituent fields. In the finished tissue,
the elastic strips in var^■ing amount border one or several terri-
tories, sometimes even smaller fields in one territory. The glue-
yielding basis-substance, formed later, is by no means as dense
and resistant as the fii-st-formed elastic substance. This is proved
by observations in inflamed periosteum. The basis-substance,
however, is densified and made resistant, not only at the borders
of the territories, but also around the ca\'ities containing the
plastids. This is the case in fibrous connective tissue as well as
in cartilage- and bone-tissue.

The so-called ^^ elastic tissue^' is evidently no tissue sni generis,
hut a basis- or cement-suhstance, of an early formation and of con-
siderable density. It arises from plastids, just as the glue-yielding
basis-substance proper,

(3) Cartilage Tissue.

History.* From the earliest time of histology to the present, true cartilage,
such as the thyroid cartilage, has been looked upon as one of the simplest

* Written by Louis Elsljer^' : "Contributions to tlie Xornial anil Pathological Histology
of the Cartilages of tlic Larynx," Archives of Laryngolo;:ry, vol. ii., 1881.

186 CONNECTIVE TISSUE.

tissues. To distinguish it from other kinds of cartilage, in which either a
fibrous or a reticuhir aspect has been recognized, it is called hyaline, i. e,,
resembling glass. The description of its structure by Meckauer, in 18,'iG,* is
essentially as that by Klein in 1 SSO,t viz. : that it consists of a firm homoge-
neous basis-substance, in which are imbedded numerous small cartilage
corpuscles. Meckauer wrote before the cell-doctrine, which has exercised
so powerful an influence upon the medical mind, had been thought of. In-
deed, that doctrine itself, as its founder, Schwann, j: has recorded, was based
to a large extent upon investigations of the constitution of cartilage. After
J. Miiller had described cartilage corpuscles that were hollow, and Gurlt had
spoken of some as vesicles ; when Schwann had succeeded, as he thought, "in
actually observing the proper wall of the cartilage corijuseles, first in the
branchial cartilages of the frog's larvae, and subsequently also in the fish," he
was led by these and other researches to conjecture "that the cellular forma-
tion might be a widely extended, perhaps a universal, in-inciple for the forma-
tion of organic substances."

Schwann considered that the cartilage corpuscles, or cartilage cells, as they
were thenceforth called, are imbedded in a matrix which is capable of produc-
ing the cells, and which he therefore called cji;oblastema. Goodsir, Naegeli,
and finally Virchow advanced the histology of cartilage in so far as they
claimed that the cartilage cells cannot possibly arise from the matrix or inter-
cellular substance. Even Vii-chow adhered, however, to the idea of Schwann,
that the cartilage cell is a vesicle filled with a more or less transparent fluid,
in which is suspended the nucleus ; and, although he was aware of the life of
the cell in general, nothing was suggested by him as to the life of cartilage.
It is true, Donders and H. Meyer had observed that the cells of hyaline carti-
lage were capable of proliferation ; § nevertheless the idea became prevalent,
more perhaps fi"om implication — because, on account of the absence of blood-
vessels, it was believed not liable to inflammation — than from any direct state-
ment to that effect, that cartilage was devoid of life. The \4tality of cartilage
corpuscles was made clearly probable by the observation of the efi'ect of elec-
trical shocks upon them, by Heidenhain, || and by Rollett,ir and the investi-
gations of Reitz,' Boehm,^ Hutob,^ and Bubnoff,'' — investigations which
except Boehm's, were made under Strieker ; it was proved positively by Heitz-
mann in 1873.^

With the question whether or not the so-called cartilage cell is alive,

* " De Penitiori Cartilaginiim Structura SyniboUe." Diss, anat.-pliys., auctore M.
Meckauer, M. D. Bieslau : ScliuUz & Co., 1836, tab. 4, p. 16.

t " Atlas of Histology." I.onilou : Siuitli, Elder & Co., 1880, ii. 48.

t "Miki'oskopisclie UuteMuchiiugen iiber die Uebereinstiinmiing iu derStructur unddem
Wachsthume iter Thiere uiid Ptiaiizeu," von Dr. Tli. Sclnvauu. Berliu : G. E.ltcimer, 18.S9,
p. 270. " Microscopical Researches into the Accordance in the Structure and Orowth of
Animals and Plants." Translated by Henry Smith. London : S3-denham Society, 1846. In-
troduction.

i Mueller's " Archiv fiir Anatomic," 1846.

II " StuUien aus dem Physiologischen Institut zu Breslau," ii. Heft, 1863.

ir Strieker's "Handbuch der Lehre von den Geweben," Article, '• Knorpelgewebe,"
1868.

1 " Sitzungsber. der K. Akadcmie der Wissensch. in Wien," Bd. 55, 1867.

^'•Beitrage zur Nornialen nnd Pathologischen Anatoniio der Geleuke." Inaug. Dis-
sertation, Wiirzburg, 1868.

3 " Untersuchungen iiber Knorpelentziindung." Wiener Med. Jalirbiiclier, 1871, p. 399.

4 "Beitrage zur Kenntniss der Structur des Knorpels." Sitzungsber. der K. Akad.
d. Wiss. in Wien, Bd. 57, 1868.

5 "Das Verhallniss zwisclien Protoplasma und Grundsubstanz im Thierkorper." Sitz-
ungsber. der K. Akad. d. Wien ; Wien, Bil. 67, 1873, and Wiener Med. Jalirbucher, 1873.

CONNECriVK TISSUE. 187

another (nu-stioii iirosc, viz. : liowciiii so isolated a corpiiscic (imbedded in a
tiriii "iiiterct'Uular" substance) obtain nutrition? It was a.ssunied tliat tlie
nourisliinj; litjuid reaches tiie corpuscle eitlier ))y diffusion or else throuf?h
eanals, or clel'ts, or fissures in the-hoinogeneous basis-substance. The idea
of the existence of juice-channels originated with Von Kecklinghuusen. He
found in silver-stained preparations of the cornea communicating colorless
spaces on a dark backgi'ouud, and believing that tlie cornea consisted of
fi))rillary tissue knit together by a cement-substance, he thought that this
cement-substance was tunneled by a system of communicating canals, " Saft-
Kaniilchen,'' and that it is this system of canals which is not stained by
silver. Innumerable investigations, under all sorts of circumstances, have
been undertaken to settle satisfactorily whether preformed juice-channels
exist in cartilage, or whether juices can be imbibed without such. In lower
animals corresponding canals had long been reported to be found, by
Queckett* and by Bergmannt in cephalopodes, and by Leydigt in various
fishes ; and certain pathological observations by Virchow, ^ Zahn, || Cornil and
Kanvier,1[ and Kindfieisch,' as well as senile changes studied by Weichsel-
baum,'^ seemed to point to their presence in man. Pigment particles were
introduced into the circulation, in the hope of discovering the manner in which
they penetrate the tissue of cartilage, by Gerlach,^ Maas,* Arnold,* and
Nykarap and Treub ^ ; Kiittner, with the same end in view, introduced solu-
tions into the trachea and examined the bronchial and tracheal cartilages ' ;
and Henoque,* Budge," Tizzoni,'" and others forcibly injected liquids as
well as solid particles into the tissues. The results of these experiments,
and of examinations vrith various re-agents, are contradictory of each
other. For instance, while Bubnoff," Hertwig,'^ Henoque,'^ Loewe,'^ Thin, '*

* '• Catalogue of the Histoilcal Series iii the Museum of tlie Koyal College of Surgeons,"
1850, vol. i., I). 102.

t " Di.s(juisitioiie8 Microscoi>ic;c de Cartilairiiiibus in specie Hyaliiiii-is." luaug. Dissert.,
Dorpat, 1850.

t " Zur Auatomie uuil Histologic der Chiriia.'ia Moustrosa." Mueller's Aicliiv, 1851, \>.
242.

§ " Eiu Fall allgenieiuer Oclironose ilcr Knorpel uiid knorpeliihuliclii-u Theile." Vir-
uhow's Archiv, xxxvii., 18G6, p. 212.

11 " Uebei riginentiufiltratiou ties Knorpi'l.s. " Ibid., Ixxii., 1878.
X " Mauuel il'Histologie Patliologifiue," Paris, 1869, p. 427.

' " Lehrbuch iler Pathologischeu Gewebelehre." i.eipzig, 1878, p. 553.

" Sitzungsber. der K. Akadeuiie d. Wiss. in Wien, Bd. 75, 1877.

s " Ueber das Verhalten de-s iudigschwefelsauren Natrons im Knorpelgewebe lebender
Thiere." Erlangen, 1876.

4 •' Ueber das Wachsthum und die Kegcneration der Hiihrciiknocliiii." Aicbiv fiir
Iclini.sclie Chirurgie, xx., 1877.

8 " Die Abseliei<lung des iudigschwefelsauren Natron im Kuorpelgewebe." VirchoWs
Areliiv, Ixxiii., 1878.

6 " Beitrag zur Kenntuiss der .Structur de.s Knorpels.'' Archiv fiir Mikroskop. Anat-
omie, xiv., 1877.

» '• Die Abscheidung des iudig.scliwefel.sauren Natron in den Geweben der Lunge."
Centralblatt f. d. Med. Wiss., 1875, No. xlii., p. 268.

s "Structure lies Cartilages." Gazette Mtdicale, 1873, p. 589 ; p. (>17.

9 " Die Saftbalineu im hyalineu Knorijcl." Archiv Itir Mikroskop. Anatoniie, xiv., 1877;
xvi., 1879.

10 " .Sulla Istologia Normale o Patologica deUe Cartilagini laliui." Arcliivio per le
Scienze Mediche, ii., 1877. " Loc. cit.

12 •' Ueber die Kntwickelung und den Bau des elastischen Uewebt-s im Netzknorpel."
Archiv fur Mikroskop. Anatomie, ix., 1873, p. 80. " Loc. cit.

" •' Ueber eiue eigenthiiniliche Zeichnung im llyalinknorpel." Wiener Med. Jahrbiieher,
1874.

16 "On the Structure of Hyaline Cartilage." Quarterly Journal of Microscopical Science,
vol. xvi., 1876.

188 CONNECTIVE TISSUE.

Ewetzky,' Petrone, t Budge, t Nykamp,$ Furbringer,|| and a number of others
consider the existence of canals in the basis-substance of cartilage proved by
their experiments and treatment of their preparations with silver nitrate, gold
chloride, hyperosmic acid, chromic acid, ammonia bichromate, etc., etc.; in-
vestigations by exactly the same means have convinced Sokolow,1I Retzius,*
Colomiatti,2 Briickner,' Toldt,'' Genzmer,' Gerlach,*^ Tillmanns,' Tizzoni,* and
others, of just the contrary ; and there is a third party which believes, with
Arnold,' that the basis-substance is made up of fiV>rillfe, that there are deli-
cate fissures between the fibrils, that these fissures penetrate the capsule,
and that " the nutrient material passes through these interfibrillar and intra-
capsular fissures into the pericellular space." Fleseh, the latest writer on the
subject, adds '" that these fissures need not necessarily be, and in fact are
not, empty, but that they are occupied by the interfibrillar cement-substance,
which, being of a "viscous soft" (zahweich) material, permits the imbibition
and conveyance of the nutrient liquid.

It is claimed that hyaline basis-substance consists of fine fibrils, so closely
held together by a cement-substance that the mass appears to be homo-
geneous. This idea, though not entirely novel, as the older anatomists seem
to have had it," has been brought forward by Tillmanns, and is doubtless
original with him.'* It is said that the interfibrillar cement-substance can be
dissolved out by certain re-agents, and then the fibrillation seen under the
microscope. According to the varying arrangement and interrelation of the
fibrillae, Tillmanns speaks of three types of cartilage tissue — viz., parallel-
fibery, net-form, and lamellous. No doubt he saw under the microscope
appearances which underlie the distinction which he thus made, but, unfort-
unately, he misinterpreted these appearances. Nevertheless, he has had
followers. Thus, Baber reported '^ that, having undertaken to test the accuracy
of Tillmanns' assertions, and not succeeding in finding the fibrillation,

* " Entziindungsversnclie am Knoriiel-'' Vorlaulige Mittlieilunjr, Centralblatt f. <l.
Metl. Wiss., 1875, No. 16; " Uutersucliungen aus dem Patli.-anat. Institut zu Ziiricli," iii.
Heft. 1875.

t " Sulla Struttura Xormale e Patologica delle Cartilagine e degli Epitelii." Xapoli. 187G.

t Loc. cit. i Loc. cit.

II "Uelier das Gewelje des Kopfknoriiels der Ceplialoiioden." Jlorpholog. Jalirbiidier,
iii., 1877, p. 453.

U " Uebfci- den Bau des Na.senknorpels," etc., ref. Canstatf s Jahresbericlit. 1870, p. 24.

1 "Bitrag till Kamiedomeu uin BruskDafiiadcD." Noid. Med. Arkiv, iv., 1872.

2 "Sulla Stiuttura delle Caitilagiui laliiii e Fibroelastica Keticolata." GazettaCliniche
di Torino, 1873, No. xxsii. ; Rivista Clinica di Bologna, 1874, No. v.; Glornale della Acad,
di Torino, 1876.

3 " rebel- Eiterbildnng ini Hyalinen Kncrpel." Inang.-Dissert., Dorpat, 1873.

4 '• Lelirbucli der Gewebelelire." Stuttgart, 1874, p. 143.

« " Ueber die Keaction des Hyalinen Knorpels," etc. Vircliow's Arcliiv, Ixii., 1875:
Centralblatt f. Cliinirgie, 1875, No. cxlvi. « -Loc. cit.

I " Beitiage zur Histologic der Geleuke." Arcliiv fur Mikroskop. Anatomic, x., 1874,
j)p. 354, 435.

s Loc. cit. ' Loc. cit.

10 " Untersuclmngen iiber die Grund.substanz des hy-ilinen Knorpels." Wiirzburg: A.
Stuber, 1880.

II See : \Vm. Hunter " On the Structure and Diseases of Articular Cartilages," Pliilosoplii-
cal Transactions, vqI. xlii., p. 514, London, 1742-43 ; M. de LJks<me, " Second Memoire sur
I'Organizatiou des Os," Mem. de 1' Academic lioy. des Sciences, tome Ixix., Paris, 1752;
more recentlj', al.so, Hoppe, Vircliow's Arcliiv, v., p. 175.

12 Loc. cit., p. 401; and"Ueber die librillare Stnictur des liyalineu Knorpels." Arcliiv
f. Anatomic u. Pliy.siologie, Aiiat. Abtli., 1877, p. 9.

13 "On the Structure of Hyaline Cartilage." Journal of Anatomy and Physiology, vol. x..
Part I., October, 1875.

CONNKCTIVE TISSUE. 189

althoufjh ho had followed Tilltniuins' method of inacoration, ho aceidoiitally
iiiadc iiioiin'iilary i)r»'.ssiir»' on the f^lass cover and tlicrciipori ol)taiiied Hatin-
fac'tory proof of the lihrillar eoustitutiou of the basis-snhHtanee. KeeveH *
has also eoiiviiieed himself of the existence of normal fibrillation in hnman
cartilii^'c. Zie<]cler seems to have done the same ; t and Flesch regards it as a
matter beyond (|Uestion. He speaks of it as "generally known and most
easily demonstrable." { Furthermore, he thinks that some portions, or per-
hai)s layers, of the basis-suljstance are mor(> compact than others, and that
this may also account for the facility of cleavage in determinate directions.

Leidy insisted ^ that tiie l)asis-substance of hyaline cartilage has a pecul-
iar filamentous structure, but his interpretation, that the granular filaments
run simply [tarallel to each other, does not cover the truth, and has not
attracted any attention. With the exception of Leidy, however, no one,
until nine years ago, seems to have questioned the homogeneousness of the
mass of basis-substance in which the separate corpuscles were supposed to be
imbedded. In 1872, Heitzmann || first proved the presence of a net-work
structure in the basis-substance. Somewhat similar appearances had pre-
viously been more or less vaguely described, but not properly interpreted or
appreciated, by Reraak, U by Heidenhain/ by Broder,'' by Frommann,' and
possilily by others.

After Heitzmann, Hertwig * observed processes of living matter pene-
trate the basis-substance of reticular cartilage ; and Colomiatti stated ^ that
he had failed to find cell offshoots in hyaline cartilage, either after treatment
with gold or silver or in viro, although he had seen cartilage-cell offshoots in
other than hyaline cartilage.

I have had the opportixnity to repeat Heitzmann's investigations under his
own eye and with his assistance, but the results as to their correctness at
which I arrived were, to the best of my belief, uninfluenced by him. I
reported in 1 875 * that I had seen the net- work structure in the corpuscles
of hyaline cartilage, in the nucleus and in the basis-substance, exactly as
Heitzmann had described it two years pre^^ously.'

In January, 1870, Tliin's memoir was published,' in which he reported
that, in particular preparations, he had seen "fine glistening fibers enter the
cartilage substance, into which, however, he has not been able to follow
them." Again : " The ordinary granular protoplasmic cells of hyaline car-
tilage are analogous, according to the views of the author, to the stellate

*"Oii the structure of the Matrix of Human Articular CartUase." BritisTi Medical
Journal, Nov. 11, 1876, p. 616.

t Beilcht (ler 50. Naturforscli. Versamiulun^ zu Mttncheii, 1877.

t hoc. cit., i>. 74.

i " Proccednifrs of the Acadcni.v of Natural Scieoces of Philadelphia," vol. iv., No. 6,
1848 ; ami Ainerican Journal of Medical Scienceg, April, 1849, p. 282.

II '• Wiener Metiiziii. Jahrbucher,- Heft iv., 1872.

T[ " Ueber die £ut8tehuug des BindegeweUes und de8 Knorpels." Archiv fiir Anatomie,
1852, p. 63. et seq. > Loc. cit.

» "Kill Hcitragzur Histologie dea KnorpeLs." Dis.sert., Zflricli, 1865.

s " UiiterHucluuifren iiber die uoi-male und pathologisclie Anatomie des Riickenmarkes."
II. Theil. Jtna, 1867, pp. 29, :iO.

* Loc. cit. » Loc. cit.

« "Transactions of the Anicnean Medical A.saociation," vol. xxvi., 1875, pp. 163, 164.

^ " Untersuchungen uber das Protoplasma. II. Das Verhaltuiss zwischen Protoplasma
und Oriindsub.stauz ini Thierkorper." Sitzuugsber. d. K. Akad. d. Wissenacb. in W:en, Ixvii.,
May, 1873.

8 It is dated August, 1875, loc. cit.

190 CONNECTIVE TISSUE.

cells of the cornea and connective tissue generally," Thin obtained, by silver-
staining, appearances similar to Heitzmann's, but unfortunately misinter-
preted them.

In 1879, Spina reviewed the subject.* He accorded to Heitzmann the
merit of the discovery, but as in the intervening seven years I alone had
publicly coiToborated it, and he was not aware of that corroboration, he
thought that "the existence of cells with solid offshoots in genuine hyaline
cartilage is not definitely proved," and undertook to settle the question.
After many fruitless attempts, he found out a method of examination "by
which ramifying cells in hyaline cartilage can be demonstrated, not only with
ease, but also with certainty." The method and the results, as he has
described them, are as follows: "The cartilage, best the ai-ticular ends of
bones, is placed into alcohol for three or four days ; then the sections are
made and the examination is conducted in alcohol. From such specimens
positive proof is obtained that the cells of hyaline cartilage have solid off-
shoots. These offshoots emanate mostly from the body of the shriveled
cells, penetrate the basis-substance, and inosculate with offshoots of other
cells. Their number and thickness are subject to numerous variations. . . .
The cell offshoots do not, as a rule, ramify. . . . Examination with powerful
immersion lenses (Hartnack, No. 1.5) teaches positively that the cell offshoots
not only pierce the capsule, but that the capsule extends also to the offshoots
themselves, so that at their origin they are surrounded, like the cell body, by a
wall. . . . Upon adding a drop of glycerine to the alcohol specimen, or on
staining it after one of the usual methods, the cell offshoots disappear more
or less rapidly ; hence, it is clear that the hyaline, structureless aspect of
the cartilage basis-substance is really due to the methods of preparation hith-
erto in use, while, when examined in alcohol, as above described, the cell
offshoots invariably become Wsible." He added that he had succeeded a fe.w
times in seeing — faintly only, it is true — the same structure in liAang hyaline
cartilages. On incorporating, for a sufficient length of time, carmine into
the body of frogs, Spina found cartilage corpiiscles of which the nuclei, the
body, and the offshoots had taken in some of the coloring matter. As the
offshoots disappeared and the carmine granules seemed to lie in the hyaline
basis-substance when a drop of glycerine was added, it is easy to see how
preNdous investigators came to be misled into siipposing the coloring matter
to have passed into the hyaline substance and into interfibrillar fissures.
With excessive caution, Spina adds : " Whether they (the coloring particles)
can also move along outside of the cell offshoots has not yet been proved."

In the same year Prudden,t and, in 1880, Flesch, t also described cilia-like
processes of cartilage corpuscles ; and the latter admitted that in exceptional
cases he had succeeded in tracing them more or less distinctly into the basis-
substance.

Variefiefi of Cartilage Tissue. Cartilage is a very dense,
opaque, and highly elastic tissue, the basis-substance of which is
not strictly gelatinous, as on being boiled it jdelds a cloudy,

* " Ueber die Saftbahncn des hyalinen Knorpels." Sitzuiigsber. dcr K. Akad. d. Wiss. in
Wien, Ixxx., Abth. iii., November, 1879.

t "Beobachtuugeu am lebendeu Knorpel." Virchow's Archiv, Ixxv., 1879, p. 185.
t Loc. cit, pp. 59-63.

CONN IK T 1 1 '/•; TISSl'J':.

11)1

(•oa«;ulatint; li(iui(l, wliicli has an odor similar to tliat of f^luc, l)iit
is not viscid. The rcticiduin of liviiii^ iiiattcr is infiltrated witli
tliis so-callt'd " cliondro'jfcnons'' l)asis-snl)stanc(', tlic cavities of
wliicli hold })lastids varying: greatly in size, nunil)er, and conflj^-
iiration. In the juvenile condition of the individual, the plastids
are ji'enerally solid and hoinoji-eneous; in the iniddle-aj^cd they
are distinctly nucleated, exliildting- a very fine reticulum of living-
matter. That these plastids
in the livinj]^ tissue are
alive, I was the first to dem-
onstrate (paf^e 116). Carti-
lage, as well as other vari-
eties of connective tissue,
should be preserved in a
solution of chromic acid;
to examine fresh cartilage
kept in pure water is very
objectionable, as in this
liquid the plastids soon
become vacuoled and de-
stroyed.

"We distinguish three
varieties of cartilage, wiiich
may be arranged according
to the order in which they
approach the structure of
fibrous connective tissue:
reticular or elastic carti-
lage ; fibrous or striated car-
tilage ; hyaline cartilage.

faj Ketkidar or Elastic
Cartilage resembles the re-
ticular variety of myxoma-
tous connective tissue. The
difference is that its basis-
substance, instead of being mucous, is dense and chondrogenous,
and is traversed in an apparently irregular manner by very dense,
bright, elastic fibers. Owing to the presence of this elastic re-
ticulum, the tissue has a yellowish color and a high degree of
pliability. (See Fig. 72.)

The elastic fibers, as a rule, are very delicate, and sometimes
are packed closely together in slender bundles, their width varj--

FiG. 72. — Reticular Cartilage from
THE Epiglottis op a Child. Chromic
Acid Specimen.

C, lij^aline cartilage traversed by fibers, R, in a
reticular arranseinent ; the reticulum surrounds the
territories of the cartilajre corpuscles ; P, perichon-
drium. Maffuificd 500 diameters.

192 CONNECTIVE TISSUE.

ing greatly in different animals. Sometimes they run parallel
with each other, sometimes they interlace in different directions.
They are coarser in the middle portions of the tissue, and gradu-
ally gi'ow thinner as they approach the periphery ; here they
often blend with the adjacent fibrous connective tissue of the
perichondrium. Not infrequently we see at the points of inter-
section of the (4astic reticulum slender oblong nuclei, which is a
positive proof that the elastic fibers have originated from branch-
ing plastids found between the territories of the cartilage
corpuscles.

The meshes of the elastic reticulum contain a chondrogenous
basis-substance, and usually in the middle of each mesh one or
two cartilage corpuscles can be distinguished. In young individ-
uals these corpuscles are either homogeneous and shining, or
composed of coarse, bright granules and destitute of nuclei.
They are more bulky in the middle of the plate of the reticular
cartilage, and become flattened toward the perichondrium, where
they undergo a gradual but rapid change into the spindle-shaped
corpuscles of the perichondi'ium. Some of the cartilage corpus-
cles are pear-shaped, and unite by means of slender, stem-like off-
shoots with the elastic reticulum. Their periphery is everywhere
thorny, which indicates that then* structure, as well as that of
the chondrogenous and elastic basis-substance, is identical with
that of all other connective-tissue formations.*

Little is known regarding the senile changes of this tissue.
It is asserted that in persons of middle and advanced age the
elastic cartilage of the am*icle of the ear becomes fibrous, and H.
Miiller has observed calcification and ossification in auricles of
dogs.

According to O. Hertwig, the first development of the elastic
fibers takes place in the shape of extremely delicate fibrillae, as
the result of the "formative acti\ity of the cartilage ceUs" in
their most peripheral portions. The further growth, he says, is
the result of " intussusception," independently of the cartilage
corpuscles. I consider the development of reticular cartilage to
be the same as that of the reticular myxomatous tissue. Territo-
ries are formed by coalescence of embryonal plastids, in which

* As a matter of curiosity, it is worth mentioning what method A.
Eollett ("Manual of Histology," by S. Strieker, American edition, 1S72)
recommends for obtaining the best specimens of reticular cartilage. "Boil
the auricle of the ear of man for a short time, dry it, and finally make sec-
tions of these boiled mummies."

CONNECT I VI-: TISSUE.

vx\

one or two plastids iviuaiu as iiiR'lian^i'!! cartilai:;!' CM)r})Uscles.
At the periphery of the territories, l)raiichiii<? phistids form, giv-
iny- rise to tlie elastic reticulum. The whole of the hasis-substance
remains traversed by a delicate reticulum of liviuji^ matter.

Reticular cartilage is met with in a few places only — the auri-
cle of the ear, the wall of
the external auditory canal,
and of the Eustachian tuljes,
the epiglottis, and the small-
est cartilages of the larynx,
including the vocal process
of the arji;ipnoid cartilages.
The tarsus of the eyelids,
which was formerly consid
ered cartilaginous, is no\\
known to be constructed ot
a very dense fibrous con-
nective tissue, riclily sup-
plied with branching plas-
tids.

(h) Striated or Fibrous
Cartilage. There is scarcely
any reason for considering
this tissue to be sui generis.
as it is invariably mixed
with hyaline cartilage,
either in its interior or
at its peripheral portions,
where fibrous cartilage es-
tablishes the connection
between hyaline cartilage
and fibrous connective tis-
sue. Fibrous cartilage,
therefore, blends with both
the last-named tissues, and

Fig. 73. — Striated or Fibrous Carti-
lage FROM THE Condyle of Femur of
A Kabbit, Eight Months Old. Sagit-
tal Section, near the Lateral Sur-
face OF the Condyle. Chromic Acid
Specimen. [Published in IS 73.]

represents a stage of tran- Tiausition of lo-aUne cirtilasf, H. into nbrous car-

sition of one into the other. "'"^"' ^- ^»s°'««'i ^oo .ua.ueteis.
Its basis-substance is glue-yielding and composed of delicate
fibriUcP, usually without a definite formation of bundles, while
the plastids are large and nucleated, either regularly scattered or
an*anged in chain-like rows. (See Fig. 73.)

According to C. Toldt, we meet with fibrous cartilage in the
13

194 CONNECTIVE TISSUE.

interartieular and intervertebral disks ; in the cartilaginous pro-
jections (labra cartilagiuosa) of concave articular surfaces, and
in those portions of the tendons which glide over bones. In the
latter instance, the cartilage corpuscles extend far into the tissue
of the tendon. In the intervertebral disks of middle-aged per-
sons, the upper and under portions consist of a tissue closely
resembling hyaline cartilage, with flat lenticular coi-puscles ; from
this layer arise the bundles of fibrous cartilage interwoven in
oblique direction. The bundles are thinner near the center, and
increase in size from within outward. The most central portion
of the disk is non-striated, of uniform appearance, and of a gela-
tinous consistence, approaching, therefore, the features of myx-
omatous basis-substance ; it is abundantly supplied with plastids
arranged in nests, like cartilage corpuscles. The lateral portions
of the disks consist of a dense fibrous connective tissue, likewise
blending with the fibrous cartilage.

The fibrous tissue which we find within hyaline cartilage,
mainly that of the ribs, the tracheal and larjnigeal cartilages,
but not in normal articidar cartilages, is of considerable interest.
Histologists claim that this fibrous tissue is a product of second-
ary or senile changes, occurring very regularly, some say between
the fifth and sixth, others between the tenth and twelfth, year of
life. A queer senile metamorphosis, indeed, which is of regular
occurrence in childhood.

L. Elsberg has observed in specimens of the thjToid and
cricoid cartilages of human foetus, five to six months old, a deli-
cately striated basis-substance in the middle of the cai'tdagiaous
plates. This striation becomes more distinct with the age of the
individual, and sometimes even in middle life invades nearly aU
the larjTigeal cartilages. The same change has been observed
in articular cartilages of so-called arthritic persons. The most
peripheral portions of the cartilage, as a rule, remain free of
fibrous metamorphosis. The fibers are arranged in either
straight or slightly curved bundles, and exhibit features iden-
tical with those of the lateral surfaces of the condyles, illustrated
in Fig. 73.

We must abandon the opinion that this fibrous tissue is the
residt of a senile metamorphosis. The question remains unset-
tled, however, whether hyaline basis-substance of cartilage is
directly changed into fibrous, or whether this transition goes on
through the intermediate stage of medidlary tissue, in accord-
ance with the general ride of tissue transformation.

CONXFA'TIVK TISSUE.

195

(c) Uf/tilinf (\trfil(iii< . The iiaiiit' implies tliat tlic dense liasis-
substance of this tissue is transparent and devoid of any trace of
structure. This is true only of cartilage specimens mounted in
balsam or varnish, sueli as were formerly used for o])servation.
Both in fresh speeimens and in those preserved in ehromie acid,
the basis-substance, even with moderate powers of the micro-
scope, is not hyaline, but of finely granular appearance.

The ))asis-substance contains cavities, in which lie the plas-
tids, termed cartilage corpuscles. Around the cavities the basis-
substance is often con-
centrically striated.
This featiire led to the

supposition that carti-
lage corpuscles
inclosed in
The capsules
ing but the
pression of different de-
gi'ees of densification,
found in all other va-
rieties of connective tis-
sue. Condensed basis-
substance in the form
of a capsule may occur p.
around single cartilage
corpuscles or around
corpuscles grouped to-
gether, and frequently
such capsules are alto-
gether absent. Their
production is closely Fig. 74.
connected with the
formation of territo-

dlirincr develon C tUe tissue of the Iiyaliue cartilage, with scattered

UUI m^ ueveiOU- g^oupg „f cartilage corimscles ; M, Meilullary spaces, con-

-Hyaline Cartilage from the Con-
dyle OF Femur of a New-born Pup. Chro-
mic Acid Specimen.

ries auring develop-
ment, and their power tainlng blodtl-vessels ami medullary tissue, ilaguitieil

of resistance can be "» '^i""'«t«'«-

proved by long-continued boiling, especially in acidulated water.
Hyaline cartilage, when fully developed, is scantily supplied
with blood-vessels ; large masses of the tissue are met with which
are entirely destitute of vessels. Undeveloped, embryonal car-
tilage, however, is traversed by a relatively large number of
meduUary canals, in which a complete system of blood- vessels' —

19G CONNECTIVE TISSUE.

arteries, veins, and capillaries — is found, besides a certain
amount of medullary tissue, filling the space between the blood-
vessels and the walls of the canals. The medullary canals,
according to C. Langer, appear in the epiphyseal cartilage of
shaft-bones (femur) after the third month of embryonal life. These
canals are all in connection with the outer fil>rous investment
of the cartilage — i. e. the perichondrium, from which the blood-
vessels enter the canals. The vascular medullary spaces decrease
with the age of the individual, although a few such spaces have
been traced up to the thirtieth year of life (Bubnoff). They are
in intimate relation with both the progressive and regressive
development of cartilage. (See Fig. 74.)

The cartilage corpuscles are never scattered uniformly
throughout the basis-substance, but always massed together,
and the amount of basis-substance between the different mem-
bers of a group of corpuscles is less than that which surrounds
the groups. The groups vary in theii- general form in different
portions even of the same cartilage. In epiphyseal cartilage of
young animals, the corpuscles are arranged in flat groups around
the articular surface ; they produce more or less globidar or
elongated clusters in the middle portion, and on approaching the
diaphysis they are arranged in elongated rows. In a sagittal
(antero-posterior) section through such an epiphyseal cartilage,
the corpuscles appear oblong or spindle-shaped along the articu-
lar surface, which indicates that their broadest diameter runs
parallel with the outer surface. In the middle portion they are
more or less globular. Near the diaphysis they again become
discoid, appear flattened, oblong, or spindle-shaped if cut in
a sagittal direction, and circular in a direction vertical to the
shaft of the bone.

With higher powers (300-500) of the microscope we recognize
that, especially in the middle portions of cartilaginous formations,
some corpuscles not infrequently lie very close to each other, so
as to mutually flatten their proximal surfaces. Between so-
called twin formations there is either a very narrow light rim or
a somewhat broader layer of basis-substance, and if an entire
group of corpuscles exhibit such twin formations (seen most dis-
tinctly in the cartilage of the trachea), the narrow frame between
the corpuscles in its regular arrangement presents a very pretty
appearance. These double formations have been considered, for
the last twenty years or more, proofs of the division of cartilage
cells. This is a very mistaken idea, for it is impossible to under-

CONNECTIVE TISSUE. 197

stand how corpusclrs iiiilxMldcd in a dense and tonjj^h hasis-snb-
stance could enlaruc an<l divide — cartilaginous tissue itself,
nioreovei-, beinji" jxTJiaps the most inactive of all tissues. These
niultiitle Itodies cannot be the products of a division, as they are
obviously formed simultaneously with the cartilage, and corre-
spond to the double or treble, etc., corpuscles so often seen in the
ten-itories of other varieties of connective tissue. They cannot
altei-. uidess the dense basis-su])stance around tliem is liquefied,
or they themselves are transformed into basis-substance.

Hyaline cartilage is a very common tissue in the body, and
is found in an amount varjdng with the age of the individual.
At a certain period of eml)ryoual development, the entire skele-
ton is composed of hyaline cartilage, and from this is devel-
oped the whole osseous system, with the exception of the flat
skull-bones. In the fidly develo})ed body this cartilage consti-
tutes all articular surfaces of the bones, the anterior portions of
the ribs, and the frame of the nose, the larjmx, the trachea, and
the bronchi.

The articular cartilage is covered with a single, often indis-
tinct, endothelial layer on the gliding surfaces, and surrounded
by a richly vascularized delicate fibrous connective tissue — the
synovial membrane — on the lateral surfaces. All other forma-
tions of hyaline cartilage are invested by a layer of a dense fil)rous
connective tissue, the perichondrium, holding numerous blood-
vessels, and in its construction more or less identical with that
of the perio.steum (see page 124). A distinct Isouudary-line
between cartilage and perichondrium does not exist, as a gradual
transition of the hyaline into the fibrous basis-substance takes
place, and the cartilage coi-puscles, which are always flattened
near the surface, blend with the oblong or spindle-shaped plas-
tids of the fibrous connective tissue.

Hyaline cartilage is prone to secondary changes. The solid
constituents increase with advancing age. According to E. Von
Bibra, the ash -remnants of the cartilage of ribs of man continually
increase with advancing age to such a degree that, while the
solid remnants of a child six months old were only 2.29 per
cent., those of a man forty years old were 6.1 per cent. Even in
middle age, many of the cartilage-corpuscles contain fat-granules,
which often coalesce into fat-globules, replacing to a certain
extent the living matter. Granular depositions of lime-salts are
often met with in the basis-substance of cartilage of the aged,
especially in the ribs and the laryngeal cartilages. Sometimes

198 CONNECTIVE TISSUE.

these are transformed into regular bone. The older a person
grows, the less hyaline cartilage is found in his body.

KoUiker made the cm-ious discovery of a "parenchymatous or cellular"
cartilage, constructed wholly of cells, without any trace of basis-substance.
Among others, the chorda dorsalis, a light line close above the earliest forma-
tion of the central nervous system in the embryo, is considered to be such a
parenchpuatous cartilage. Such a thing, however, is contrary to all we know of
what could possibly be any variety of connective tissue. According to V. v.
Mihalko\acs, the chorda dorsalis is no cartilage at all, but a duplicature of the
outer, epithelial germ-layer (Toldt). If this be correct, it woidd be another
instance of an epithelial elongation which, after returning to the condition
of an embryonal and medullary tissue, gave rise to connective-tissue forma-
tions. We know that this is the ease with the thyi'oid body and the enamel-
tissue of the teeth.

The Structure of Hyaline Cartilage.*

Fresh, articular cartilage is a suitable object for the study of
the histology of hyaline cartilage. If we place a thin section, to
which is added a drop of one-half per cent, solution of common
table-salt, under the microscope, with an immersion lens No. 10,
we will find a number of details heretofore overlooked. The
following description is a study of a specimen taken fi'om a hori-
zontal section of the condyle of femur of a young, full-grown dog ;
it answers to the corresponding cartilages of the cat and the
rabbit.

The bodies of the cells appear finely granular, bounded by a
somewhat denser layer. The contour of the cartilage cell being
accurately in focus, there appears between the cell and the basis-
substance a light, very narrow rim, which is traversed by numer-
ous extremely delicate, radiating, grayish thorns or streaks. All
these thorns are conical, the broad base emanating from the body
of the cell and the thin point directed toward the basis-substance.
\^Tierever two cells lie close together, the light rim between them
is pierced in a transverse direction by grayish threads.

When in the cell the nucleus is distinctly \^sible, its shape
will be found to correspond to the shape of the cell- body, and in
its finely granular interior the bright nucleolus will be usually
apparent. A narrow light rim is found to surround the nucleus,
which, on being sharply focused, shows radiating thorns, whose

* Translated fi'om "Studien am Knocheu und Knorpel." Wiener Mediz.
Jahrbiieher, 1872.

CONNECTIVE TISSUE.

199

bases oiimnato from the nucleus, and whose })oiuts l)k'ncl with
the protophistua of the cell. These conical spokes are clearly
dcftiit'd oidy when the liji,'ht rim around tlic luudeus is distinct.

On carefully examininj:^ the basis-substance, a very delicate,
almost granular, couforniation is recognizable, as if dark fields
were alternating with light ones, and in some platres giving the
impression that the light fjelds formed ramifications, or even a
delicate net-work.

With the knowledge that from the cartilage cells offshoots
emanate, and the l)asis-substance has an indistinct reticular for-

FiG. 75. — Hyaline Cartilacje from the Border of the Condyle op
Femur of a Young Dog. Transition into Fibrous Cartilage.
Stained with Nitrate of Silver. [Published in 1872.]

iS, light spaces witli indistinct cartilage corpuscles, freely branching and connecting ; JB, dark
brown basis-substance, traversed bj' a light reticulum. Magnified 800 diainuters.

mation, and under the impression of pictui-es of inflamed carti-
lage, w^hich will be dwelt upon later, I proceeded to stain the
cartilage with nitrate of silver.

I prepared the articular extremity of the femur by removing
the muscles and severing: the shaft at a certain distance above

200 CONNECTIVE TISSUE.

the knee-joint, and in this way obtained the condyles, as it were,
on a handle formed by the stump of the femur. After the sjtio-
via was washed off, I rubbed a stick of nitrate of silver for several
minutes over the condyles, transferred the specimen to water, and
exposed it to daylight. After a few days, the parts which had
been brought in contact with the re-agent became dark brown.
The most superficial layer was removed as useless, and the next
layer was examined. I would remark that sections from deeper
portions, which at first are but slightly tinted by the silver-salt,
assume a deep color on exposure to daylight. The deeper layers
of the condyle, too, are dyed brown, and to a certain depth are
well adapted for new sections.

The following description is that of specimens taken from
the condyles of a young and an old dog: they showed the same
features.

From the stained specimens taken from the anterior and
under portions of the condyle, I could obtain nothing satisfactory
for establishing the idea of a reticular structure. As soon, how-
ever, as I reached the lateral surface, close to the edge, the aspect
of things at once became changed. (See Fig. 75.)

The basis-sul)stance at the borders of the cartilage cavities
is stained dark brown, in other portions light brown-red. From
the cavities of varying shapes light offshoots are thrown out in
different directions, which may " be grouped in three orders,
according to their calibers. The broadest offshoots, those of the
first order, either connect cartilage cavities, or run merely into
the basis-substance. The somewhat nairower offshoots, those
of the second order, project from either the cartilage cavities or
the broader offshoots, and ramify freely into the very narrow
ones, those of the third order. The latter shoot out from the
cartilage cavities and the processes of the first and second order,
as well as fi'om the cuds of coarser processes, and traverse the
basis-substance throughout. Thus a rich, extremely delicate
reticulum of light, irregular lines is produced, with numerous
varicose enlargements, the meshes of which reticulum are filled
with the brown basis- substance. In the cavities we recognize
the dim, unstained cell-bodies, with their enlarged, thorny nuclei
and their offshoots, whicli are traceable into the processes of the
cavities of the first order.

In sj)ecimens taken from the anterior and under surface of
the condyles, offshoots of the thii'd, and occasionally some of the
second, order are found, which are readily distinguished, wherever

CONNECT I T 'E TIS.^ UE.

201

the l)Oi'(l(MS of tho cartilan;*' oavntics avo pieroed byradiatiiif; light
lines. Till' lateral surfaces of the eondyles, on the contrary, con-
stantly exhibit cartila,u;e cells witli offshoots of the first order,
vvhicli are more numerous the farther away from the border of
the articular surfaces. In the region where the basis-substance
of tlie cartilau'e beu'ins to be striated, we find the most beautiful
silver images ; here the coarse offshoots, interconnected by deli-
cate ones, are very numerous, and remain so in the fibrous car-
tilage })i-o])er, and also in the tissue of the periosteum and the
tendon, adjoining the liyaline cartilage.

My next purpose was to stain cartilage with chloride of gold.
I placed the condyles of the knee-joint — the stump of the femur

^■"-<>,

^

'" "'^,

Fig. 76.— Hyaline Cartilage from the Condyle op the Femur op an
Old Dog, Stained with Chloride of Gold. [Published in 1872.]

C, rt.irk violet cartilage corpuscles, with inilistinct nuclei and numerous delicate dark
violet offshoots. B, pale violet basis-substance, ti-aversed by a partly dark violet, partly light,
reticulum. Mairnified 800 diameters.

again serxdng as a handle — into a one-half per cent, solution of
chloride of gold, and traced its action on the cartilage for from
ten minutes to twelve hours, always after rejecting the most
superficial sections.

The gold stain of the cartilage corpuscles appeared in fifteen
minutes ; in the violet cell-bod}' the nucleus became easily
seen and sharply marked ; the contour of the cell-body was also
rendered more distinct. In many place's the conical spokes

202 CONNECTIVE TISSUE.

arising from the cell -bodies became violet, but coiild not be traced
into the basis-substance any farther than in uncolored specimens ;
in specimens from the lateral surfaces, numerous coarse and
thorny offshoots of a violet color were seen, similar to that of
the cell-bodies themselves, while the basis-substance remained
uncolored or was pale bluish-red.

After one hour's action of the gold solution, the coarse off-
shoots and the cells appeared dark violet, the offshoots of the
second order became distinctly visible; some of the offshoots of
the third order could be traced far into the basis-substance, or
directly into cells near each other.

After twelve hours' action of the gold-solution, formations
were brought into view which, being granular and crumbly, did
not deserve attention. The cartilage cells were dark violet, the
nucleus recognizable, if at all, as a lighter field. From all around
the cell-body projected delicate offshoots, most of which looked
finely granular, and in many places joined a granular reticu-
lum. The reticulum is most abundant in the immediate vicinity
of the cell and on the borders of the ceU territories ; it connects
directly with neighboring cells, and in some places is so compli-
cated that a precise definition is impossible, even with an immer-
sion lens No. 10. In places where the image is incomplete, we can
satisfy ourselves that we have to deal with a reticulum which is
richly supplied with granular and varicose nodulations, and the
connection of which with the cell-bodies is beyond doubt. Fig.
76 illustrates such a pictui-e.

At the points of transition of cartilage into bone, there exists,
as is well known, a layer of cartilage cells, the basis-substance of
which is calcified. A calcareous deposition in the cartilage can
be produced also by inflammation, following certain injuries of
the cartilage. In horizontal sections of fresh, calcified specimens,
as weU. as in specimens deprived of their lime-salts by chromic
acid, we recognize that the basis-substance is traversed by chan-
nels, which hold offshoots emanating from the cell cavities, and
producing a net work. The image of these offshoots is the same
whether much or little lime-salt be present, either in the wall of
the cavity bordering the cell- body or at the boundaries of the
cell territories. We are satisfied that in all cases a deposition of
lime-salts has taken place in the fields of the basis-substance,
while the cell and its offshoots have remained unchanged. In
old animals, where the calcified cartilage directly borders the
bone- tissue, positive proof can be obtained that the " osteoid"

CONNECTIVE TISSUE.

203

cells are, by means of offshoots, directly connected with tlie
bone-cells.

The results of my researches lead to the following con-
clusions :

The bodies of the cartilage cells have radiatiuf/ offshoots. These
offshoots form a delicate varicose reticulum in the hasis-suhstance.
At the points of transition of hyaline cartilage into striated.,
fibrous curtilage and into periosteum, the offshoots are verg large
and broad ; they connect neighboring cells, either directly or indi-
rectly, by means of delicate offshoots.

In 1872 I was not yet acquainted with the structure of
bioplasson — /. e., the cell-body, nor had I then recognized the

Fig. 77. — Hyaline Cartilage in Transition to .Striated Cartilage,
PROM THE Border of the Condyle of Femur of a Grown Dog.
Stained with Chloride op Gold.

C, (lark violet cartilage corpuscles witli distinct nuclei, projecting offsliools, 0, which
ilirectlj- or indirectly connect the corpuscles ; B, pale violet basis-substance, exhibiting a
partly dark violet, partly light, reticulum. Magnified 800 diameters.

significance of the interconnection of cartilage corpuscles for
elucidating biological views in every respect contradictory of the
cell theory. Still, I felt confident that, on account of the sim-

204 CONNECTIVE TISSUE.

plieity of the methods used, other iuvestigators would encounter
no difficulty in producing what I had produced and seeing what
I had seen. But what happened was just the contrary. A large
bulk of literature was produced on this subject ; nevertheless,
almost all observers failed in bringing to \dew the connections
existing between the cartilage corpuscles. Some claimed that it
was the synovial liquid Avhich assumed, on treatment with nitrate
of silver, the figures I described; others that the connections
between the cartilage cavities could be found only in the super-
ficial portions of the condyles ; still others believed the forma-
tions seen by me to be artificial products, due to a precipitation of
the metal-salt I had employed. All, however, agreed that the
light reticula which eventually became visible in the silver-
stained specimen were only juice-canals, according to views
taken by Von Recklinghausen.

Meanwhile I had convinced many hundi-ed students, in my
laboratory in New York, that the cartilage corpuscles are really
connected with each other, and an unprejudiced observer, L.
Elsberg (see page 138), publicly announced his conviction of
the correctness of my assertions.

In the fii-st place, there coidd be no doubt that the negative
image produced by the silver in every respect answers to the
positive image brought out by the gold. The negative silver
image obtained from the border of the condyles, where the hya-
line cartilage begins to change into fibrous cartilage (see Fig.
75), fully corresponds with the positive gold image produced in
the same place. Fig. 77 is an illustration of specimens which
for j'-ears I have used for demonstrations in my laboratory.

Secondly, I was desirous of satisfying myself if the method
of treatment with silver was really so unreliable as claimed by
some writers. I gave Dr. W. Hassloeh, a physician of unusual
cleverness, attending my laboratory in 1878, my printed pam-
phlet containing directions for procedure, and the fresh condyles
of a human foetus, six months old. A f(^w days later, without
any further advice on my part, the gentleman showed me a
large number of specimens, exhibiting images precisely similar
to those illustrated in Fig. 78. The identity of the light spaces
Avith cartilage corpuscles was beautifully demonstrated in the
thin sections, where dark brown layers were directly followed by
slightly stained or unstained layers.

I admit, however, that my assertions would not have deserved
much attention had the staining methods with nitrate of silver

CONNECTIVE TISSUE.

205

and c'liloride of yolcl bei'ii the (july t'ouiidution on which they
were based. But I said, in 1872, that cahufied portions of the
hyidine ('artihiiiv, the cah'ification l)ein<i a ju-odiK't either of a
normal j)ro('ess preceding- ossifieation, or of a process of inllani-
mation artificially induced, exhibited the reticulum and the
offshoots of the cartilage corpuscles in the larger projections
of the cavities, without the application of any re-agent. The
increased refracting power of the calcified basis-substanee is
sufficient by itself to bring to view everything that can be seen
in the silver and gold specimens, and everything which can be
deduced from a comparison of both. The images obtained in
the earliest stages of infiammation of any variety of connective
tissue are very valuable means of convincing ourselves of the

Fig. 78. — Hyaline Cartilage from the Condyle of the Femur of a
Human Fcetus, Six Months Old. Stained with Nitrate of Silver.

S*, single lijrht space; .52, twins, directly connected by light lines; B, dark brown basis-
substance pervaded by a light reticulnni. Magnified 1000 diameters.

presence of a large amount of living matter within the basis-
substance. There is, indeed, no way to understand the inflam-
matory process unless explained in this manner.

A. Spina (see page 141), by the alcohol treatment of the car-
tilage, discovered an excellent method for demonstrating the
connections of the cartilage corpuscles. An eye with very little
experience can observe to-day what, in 1872, I fii'st maintained,
after a long and tedious research and laborious experiments.

206

CONNECTIVE TISSUE.

The Structure op the Thyroid Cartilage. By L, Elsberg.*

Longitudinal sections through the lateral j>lates of the thyroid cartilage of
a man of about twenty-five years, hardened in chromic acid and stained with
an ammoniacal carmine solution, exhibit with low powers of the microscope

V*

^^^■'^\ ■r'«-r,fv

0> ln|\^i

f

^^/,j.

#

■^

T'n-

PL,

^ s

(150 to 200 diameters) the following: The cartilage corpuscles, either single,
in pairs, or in groups of from three to six, or even more, are imbedded in a
basis-substance which, for the most part, is homogeneous-looking or indis-

* " Contributious to the Normal an<l Pathological Uistology of the Cartilages of the
Laryux," Archives of Larj'iigology, vol. ii., 1881.

CONNECTIVE TISSUE. 207

tinetly ^raiiulur, but in sotnc jiortioiis fiiioly striiitod. The horaoKencous or
indistiiu'tly fjraiiular-lookiiif^ l)asis-su])staii('e is that vvliich bears tin- name
liyaline basis-substanee; tlio striated is termed (il)rous, ultliough actual librilla;
appear only ou the edges of the specimen, or when the tissue is torn and
mutilated. The fibrous basis-substance is intermixed, without any regularity,
with the hyaline, and usually sharply separated from it. Not infrequently a
number of cartilage corpuscles, or groups of cartilage corpuscles, are sur-
rounded by fibrous basis-substance, the striations of which run, as a rule, in
a sagittal direction, /. c, vertical to the surface. Within the fibrous basis-
substance the cartilage corpuscles are at most points sparsely scattered or
absent ; here and there, however, they are more numerous, in rows or elon-
gated, corresponding to the direction of the striations. It also occurs that
striated portions of the basis-substance contain very minute globular or
oblong corpuscles, sometimes to such an extent that the striated structure is
concealed by the large number of these corpuscles. (See Fig. 71).)

The fibrous portion is seen to occupy the center of a longitudinal section
of one of the plates of the thyroid cartilage. This is not regularly the case
in every cut, and was exceptionally well marked in the section from which
the drawing was made. In some sections the fibrous cartilage is altogether
absent, but every laryngeal cartilage contains some fibrous mixed with hya-
line portions.

Under higher magnifying powers (500 to 600 diameters), single cartilage
corpuscles exhibit features, frequently before described, with coarsely granu-
lar nuclei. Around the nucleus finer gi'anules are visible. At the periphery
of the cartilage corpuscle there are several strata of higher refracting power,
especially the zone nearest the basis-substance, which, as a rule, appears
very shining and is what is termed the capsule of the cartilage eoi"puscle.
Not infrequently the cartilage corpuscle is very indistinct, being but slightly
more granular than the siirrounding basis-substance ; then almost nothing
but the nucleus marks its presence and its place. In twin formations of car-
tilage corpuscles, which are often met with, the zone of division between the
two corpuscles is identical with that surrounding both, in the shape of a cap-
sule. Of the same nature are the zones of division that are seen in clusters
of cartilage corpuscles.

The so-called hyaline basis-substance throughout its whole extent now
appears finely granular ; as a rule, the gi-anulation is more distinct midway
between the coi"puscles than in their immediate vicinity. The fibrous por-
tions of the basis-substance are seen to be made up of extremely minute
spindles, which, by being grouped longitudinally, produce the aspect of
striation. The spindles or fibers are separated fi'om each other by light
rims, and both the spindles and the rims look finely granular. Between the
spindles may often be seen small globular bodies, sometimes scattered, some-
times in clusters, of which the size and shape greatly vary, reaching occa-
sionally the size and shape of a regular cartilage corpuscle. In some striated
fields, blood-vessels, both arterial and capillary, can be seen ; the former with
the characteristic muscle-coat, the latter with the endothelial wall, besides
holding red blood-corpuscles in their calibers.*

The highest powers of the microscope (1000 to 1200 diameters) reveal

* These, striated fields are remnants of former medullary spaces, for the striated portions
in the center of the cartilage never contain blood-vessels.

208

CONNECTIVE TISSUE.

the reticular structure of cartilage corpuscles, as it is known since 1873. All
granules within the nucleus and all granules within the corjiusele are unin-
terruptedly connected by delicate threads. The intranuclear net-work is con-
nected with the corpuscular reticulum by radiating conical spokes traversing
the light rim around the nucleus; and, at the periphery of the corpuscle,
similar conical spokes pierce a nan'ow light rim and enter the basis-sub-
stance, in which, especially in the highly refiacting zone termed capsule,
they are usually lost to sight. Cartilage corpuscles, even, which have become
so pale as to leave only a dim trace of their former contour \-isible, still
exhibit more or less distinct traces of the reticular structure.

The same structure may be seen throughout the so-called hyaline basis-
substance — more distinct in the middle of the space between the corpuscles
than immediately around the eoi-puseles themselves. The fibrous portion of

—J

Fig. 80. — Thyroid Cartilage of Adult. Sagittal Section.

C, C. cartilage corpnscles ; B, intUstinctlj' reticular hyaline basis-substance ; F, flbixras
basis-snbstanco. Magnified 1200 diameters.

the basis-substance has also a reticular structure. The bodies of the slender
spindles show a net-work without the application of any re-agent, and the
light rims between the spindles are traversed by deUcate threads running in
a vertical direction to the longitudinal diameter of the spindles. All granules
and lumps scattered through the fibrous basis-substance are surrounded by
light rims, which are pierced by conical spokes inosculating with the reticu-
lum of the neighboring spindles. (See Fig. 80.)

I have treated sections of the same cartilage, after they had for several
days been washed out with distilled water, with a one-half per cent, solution

CONNECTI VE TISSUE.

209

of gold cliloriilc, wli(>roupon tlioy assumed a dark purple color, and showed
all the features descrilx'd. somewhat more distinctly than simple carmine
pre])arations. I deem their detailed description unnecessary.

When I became acquainted with Spina's researches (see page 141), I
deemed it of importance to repeat tlie examination according to his method.
I therefore jdaced a larvnix, immediately after removal from the body of a
girl, aged twenty-four years, into strong alcohol, and after four days made
thin sections from the tli,\Toi(l cartilage in a horizontal direction, transferred
them in alcoliol to the slide, and examined them with both low and high pow-
ers, adding, from time to time, a drop of strong alcohol to prevent the speci-
men from drying. The appearance presented by such a specimen is truly
surprising. As a matter of course, the cartilage corpuscles are shriveled up,
so that more or less space is left between their jagged periphery and the bor-

FiG. 81. — Thyroid Cartilage of Adult, kept in Strong
Alcohol. Horizontal Section.

C, sbriveled cartilage corpuscle; O, longitudinal offslioots; -B, reticulum in basis-sub-
stance; G, granules of living matter. Magnified 1200 diameters.

der of the basis-substance. With an amplification of 500 diameters, the
basis-substance is seen pierced by light filaments, which, in many instances,
can be traced through the intervening space into the body of the cartilage
corpuscle. Most of these filaments radiate around the corpuscle, and, imme-
diately after penetrating the basis-substance, diverge and form a reticulum
throiighout its extent. Cartilage corpuscles located near each other are
directly connected by non-ramifying, and occasionally by ramifying, ofifshoots,
or by bundles of such offshoots of a more or less parallel course. The reticu-
lum in the basis-substance is either radiating or irregularly arranged around

14

210

CONNECTIVE TISSUE.

the corpuscle. Contrary to the assertion of Spina, the filaments or offshoots
do, as a rule, ramify, except those that directly connect the neighboring cor-
puscles. Sometimes thick bundles of offshoots emanate from opposite poles
of the corpuscles, while intervening portions of the periphery are almost
devoid of offshoots. Toward the peripherj- of the thjToid cartilage,— where,
as is well known, the cartilage corpuscles elongate, becoming smaller and
spindle-shaped and more or less parallel to each other,— the offshoots are
given off rectangularly to the axis of the corpuscles.

High magnif\-ing powers, immersion lenses No. 10 and No. 12, con-
clusively prove the connection of the offshoots with the cartilage corpuscles.
Portions of the basis-substance which, with lower powers, looked only granu-
lar, now show a delicate reticulum, which, even when coarser offshoots are

^*:6}H

'^^^m!'"^&l'-.MMiuM

Fig. S 2.— Thyroid Cartilage of Adult. Horizontal Section.

C, C, cartilage corpuscles; F, fibrous portion of cartila-e; G, grauiUes of living matter.
Magnified 600 diameters.

wanting, is connected with the cartilage corpuscle through deUcate and more
or less conical offshoots from the surface of the corpuscle.

The light interstices between the fibers of striated basis-substance are
also traversed bv delicate grayish thorns. Such thorns are ^•isible even in the
perichondrium. ' Through the fibrous bundles of the perichondrium run, in a
nearly rectangular direction, delicate light streaks, while the interstices
between the bundles, and the spaces left between the corpuscular elements
and the bundles, exhibit delicate conical grayish threads, the direction of
which corresponds to these light streaks. (See Fig. 81.)

The highest powers of the microscope disclosed in one of the specimens
examined another feature in the hyaline basis-substance, viz. : the presence
of a number of granules or minute lumps of varj-ing shape, some interwoven

CONNKCTl VK TlSSl'K.

211

with the (Hroc't offshoots of the corpuscleH, and some with the throads foiiniiiK
the liner net-work of the Imsis-substance. They appeared to be thickene<l
points of intersection, knots, or nodes, composed of the same material as the
oiTslioots and threails tliemselves. They were uncpiestionably f^-annles of
iivint; matter. I found their (greatest dev(dopraent in a case exaniini'd witiioiit
Spimi's metliod — a case wliicli I sliall describe presently.

The observation which I am nowal)ont to record was made in specimens of
the thyroid cartilage removed from the body of a rather stout raaji, forty-eight
years old. After having been hardened in chromic aci<l solution, without any
other re-agent, they exiiibited formations in the basis-substance which, so far
as I am aware, have never before been described. I have alluded to them as

/-f'-'t''

-ik.

■X%

'^^^S

FiG. 83. — Thyroid Cartilage of Adult. Horizontal Section.

C, cartilage cori>usclc ; J5, hyaline basis-substance ; fi?, granules of living matter. Mag-
nified 1200 iliameters.

found in one of the specimens examined, with the highest powers of the
microscope, by the alcohol method of Spina.

As to the cartilage corpuscles in these specimens, many of them were
larger and more coarsely granular than are commonly observed ; otherwise,
their characters and the arrangements of the basis-substance, both so-called
hyaline and fibrous, were like those described before. The intranuclear,
intracorpusciilar, and intercorpuscular net-works were with high powers well
shown.

The very remarkable feature was that, with qiute low power, the basis-
substance was seen to be speckled and studded with granules or lumps, varying
from that of a point at the limit of the \isible to that approaching the dimen-

212 CONNECTIVE TISSUE.

sions of a regular cartilage corpuscle. Of course, no one must for a moment
think of anything like the pathological conditions that have been described,
either as granular degenerations of the cartilage basis-substance, or as in-
crustations of the corpuscles. Not only were the appearances entirely differ-
ent and the cartilage healthy, — as otherwise ascertainable, as well as from the
known condition of the man and of the cause of his death, — but the true
nature of the lumps was made perfectly clear by examination with higher
powers. (See Fig. 82.)

When magnified to the extent of 000 diameters, the same relative appear-
ance was preserved. The lumps in the basis-substance still varied in size,
from the limit of the visible to the magnitude of ordinary cartilage corpuscles ;
but, in all the larger lumps, differentiations were visible which approached
them in structure, as well as in size, to cartilage corpuscles. In some, one
or more vacuoles, in others, a small or large nucleus, or even two nuclei,
could he made out; and a few (i. e., occasionally one in some fields) showed
iiTcgular twin, or even triplet, formation.

The highest power threw a wonderful light upon these lumps. They were
seen to be masses of living matter. The larger showed a net-work in their
interior, some without and some with a nucleus, and the latter, when present,
was sometimes homogeneous and sometimes reticulated. All the lumps,
except the smaller, were sun-ounded by a distinct light seam, through which
radiating conical offshoots passed to the net-work in the basis-substance;
and all of them, even the smallest, sent delicate offshoots connecting them
with that net-work, or were themselves part and parcel (i. c, thickened points
of intersection of the threads) of that net-work. (See Fig. 83.)

After ha\'ing studied such a specimen, it was easy to interpret con-ectly
the intrareticular granules seen in the alcohol specimen represented in
Fig. 81.

Development of Cartilage* Hyaline cartilage is developed, in
the same way as fibrous tissue and bone, from the indifferent
medvdlary elements which, in human embrj'os, between the fourth
and fifth month, and in newly born dogs, cats, and rabbits, are
stored up in a still considerable amount in the vascularized
medullary spaces of the cartilage.

Upon the authority of Schwann, the erroneous view has been
generally held that blood-vessels are found in hyaline cartilage
only a short time before commencing ossification. In early
periods of development of cartilage, medullary spaces are pres-
ent containing blood-vessels, — viz. : arteries, veins, and capil-
laries,— which, as Bubnoff t has demonstrated, are preserved to
quite an advanced age.

In .such spaces we find, besides a varying number of blood-

* " Untersuchungen fiber das Protoplasma. IV. Die Eiitwiekelung der
Beinhaut, des Knochens und des Knorpels." Sitzimgsber. der Akad. d.
Wissensch. in Wien, 1873.

t Sitzungsber. der Wiener Akademie d. Wissensch., 1868.

CO^yECTlVK TISSCE. 213

vessels, medullary tissue, ('(>nsistin«i:()t' globular or spindlo-shapcd
corpuscles, with a sliijlit auiouut of a uiyxouiatous and fibrous
reticular l)asis-sul)stauc(\ Lower powers of the niicrosco])e reveal
that the boundary line between ineduUary and cartihiji^e tissue; in
soiue places is sharply defined, while in other places it is indistinct
or invisilde. Tn the most pei-ipheral ])ortions of the m<'<lullary
tiss\ie, /. I'., nearest the cartilagv, we see rows of spiudle-sliapcd
or obh)ng^ bodies, bear-
ing; a close resemblance
to the medullary cor-
puscles found on the
boundaries of forming?
bone-tissue. (See Fig.
84.)

In the cartihige of
the knee-joint, at the

extremity of the femur ''^^^/^".o i """"' -^^

of new-born pups, we
meet not infrequently,
at the borders of a
medullary space, close
to the fully formed car-
tilage, with groups of \'^''^7JAK"
medullary corpuscles, '^/''^ "^Z^/ / /^^^ ^' T^-^^

the peripheral portions fj ^^^/gP^ %%> VA^^'^^^
of which are beginning U^yj'^^^ ^ --V~^^^.\o
to be infiltrated with ^^, fy[^d>[ ^^

an apparently homoge- f/^^\i^fr^^^'ik!^H>^'

neous basis-substance, '^ll
while the central por-
tion retains the charac- Fig. S4.- Hyaline Cartilage op the Condyle
r, ,, ... OF Tibia of a Human Embryo, Four Months
ter of the cartilage cor- ^^^ Sagittal Section. Chromic Acid
puscle. Under these specimen. [Published in 1873.]

conditions, honiOgene- ,^ ^^^^,^,^^^,.^. ^^^^^^, t,,„,,,,,ely cut, contaimn,^ blond.

OUS (in the optical di- vessels aii<l nudiiUaiy tissue ; C, cartilage, with inaiked

i • ■ 1 \ territories in the basis-substance. Maenifietl 200 diam-

ameter semicu*cular) |;jp,."

fields are projected into

the caliber of the medullary space. Or a gradual transition of

medullary into cartilage tissue takes place at the border of the

medullary space, with the result that a number of spindle-shaped

medullary corpuscles are transformed into a tei-ritory of cartilage

tissue, which in this situation sometimes exhibits a delicate

^^

214

CONNECTIVE TISSUE.

striation. In the first case, the result is a globular territory with
a ceutral cartilage corpuscle ; iu the latter, a spindle-shaped terri-
tory, containing an elongated, spindle-shaped corpuscle. (See
Fig. 85.)

There is a marked difference, however, between the territories
of the cartilage in very young and in fully developed animals.
In the articular cartilage of human embryos from four to five

Pig. 85. — Hyaline Cartilage of the Condyle of Femur of a New-born
Pup. Sagittal Section. Chromic Acid Specimen, Slightly Stained
WITH Chloride of Gold. [Published in 1873.]

V, loop of a capillary blood-vessel in a medullary canal of the cartilage : /, elougateil
medullary coipuscles in the stage of indifference ; B', boundary zone of basis-substance ;
.82, fully developed basis-substance. Magnified 800 diameters.

months old, and that of newly born dogs and cats, the latter being
at birth as far advanced in development as man at four or five
months, we see territories only, with numerous cartilage cor-
puscles, between which the basis-substance is scanty, as if sprung

CONNECTIVK TISSFE. 215

from a few fiiilu'vonal (mt'ilullarv) (^orjiusclcs, or from a siii^lf
eori>us('lt>. In the full-grown animal, on the contraiy, the terri-
tory contains hut one ov a few eartilatie eoi-pnseles, the double
and tri})le formations, })etween which the basis-sul)stanee is very
scanty or even absent, while in the peripheral portion of the terri-
tory a lar<;e amount of ])asis-substanee is found, which must have
ori«i:inated from a eorrespondinj^ large numlier of embryonal
(medullary) corpuscles. Although the cartilage cor{)uscles of verj'
young aninuils are decidedly smaller than those of the full-grown,
there is not the slightest evidence of a so-called " interstitial
gi-owth,'' /. e., an increase of the bulk of the corpuscle as well as of
the basis-substance already formed. It is far more probable that
the embrj'onal cartilage is not the same formation from which
the cartilage of the adult arises ; it certainly is not in the same loca-
tion as far as the size of the whole body is concerned. Besides,
a fully formed cartilage, or any other tissue, grows, during the
time that the cartilage is returning to the medullary condition,
only in limited places, when a new grouping of medullary cor-
puscles takes place, and a new basis-substan(;e is developed.

Those who maintain that an "interstitial" growth takes place,
forget that a cartilage corpuscle, once imbedded in the dense,
chondrogenous basis-su})stance, cannot increase in size unless a
liquefaction of the basis-substance has occurred, at least at the
borders of the cavity containing the corpuscle. The same objec-
tion can be raised against the h\"pothesis of the division of carti-
lage corpuscles in the fully developed tissue. The probability is
far greater that cartilage grows with the growth of the whole
body, from medullary corpuscles at the periphery, while the
central portions are reduced into medullary tissue for the ])enefit
of the growing bone-tissue. The "apposition theory" considered
in this light is the only legitimate one, as there is no diflticulty in
understanding that from the perichondrium, or other peripheral
formations of connective tissue, always, of course, through the
intervening stage of medvdlary tissue, new cartilage is produced
during the whole period of development of the body.

The process of development of cartilage with striated basis-
substance is materially the same as that of hyaline cartilage, as I
could trace on the lateral surfaces of the condyle of femm* of
growing rabbits. Here we find intermediate striated cartilage
between the hyaline cartilage and the tendon or ligamentous
tissue ; and the intermediate striated portions may be found to
contain fields of hyaline cartDage. With such evidences it is not

21 G CONNECTIVE TISSUE.

difficult to convince oneself that the character of the cartilaginous
basis-substance, whether hyaline, striated, or fibrous, depends
upon the shape and the grouping of the original, indifferent
medullary corpuscles alone.

The cartilaginous callus, obtained after subcutaneous fract-
ures of the leg-bones of dogs and cats, I found very suitable for
the study of the development of cartilage. Here the new forma-
tion of cartilage arises from nests, identical with medullary
spaces, which in their center contain blood-vessels, at their
periphery spindle-shaped elements, as the result of the inflamma-
tory new formation. The medullary elements close around the
blood-vessel are globular, and are succeeded by layers of spindle-
shaped bodies, the nuclei of which are partly faded, indicating
that these formations are in the stage of transition from a uni-
form granulation into the stage of infiltration with glue-yielding
basis-substance. In such inflammatory nests, also, we observe
the transformation of capiUary blood-vessels into solid strings,
and afterward into small medullary elements. The process is
the same as in the involution of bone-tissue, due to normal senile
changes. In the same cartilaginous caUus we also encounter
numerous nests in which red blood-corpuscles and blood-vessels
arise from cartilage corpuscles (see page 98), and these forma-
tions precede the liquefaction of the calcified cartilaginous basis-
substance, which occurs previously to the production of new
medullary tissue and of bone.

The embryonal or medullary elements are, under aU circum-
stances, the formers of tissue. Those from which bone arises
have been termed *' osteoblasts " by Gegenbaur, who considered
them to be, specifically and exclusively, bone-formers. We are
far from understanding the specific nature and limits of embry-
onal corpuscles, and the designation ^'osteoblasts" is therefore
superfluous. We might with equal propriety speak of *' periosto-
blasts," '' chondroblasts," etc., while, in fact, aU these tissues
originate from one and the same source — namely, the medullanj
tissue. What character the territory will assume, what will be
the nature of the basis-substance in the territory, depends upon
the grouping of these many-named "l)lasts"in the stage of indif-
ference preceding the new formation of a tissue.

In 1873, I admitted the possibility that, under certain physio-
logical conditions and changes, one variety of basis-substance
might be.directly transformed into another ; periosteum, f . i., into
bone or into cartilage, hyaline into striated cartilage, etc. This

COXNECTIVH TISSrK. 217

possibility seems to me, to-day, to be very slif;lit, so iiiucli so
that even a direet transformation of hyaline into fibrous carti-
hijji' is doubtfnl. / <nii positive that one I'aricfi/ of Ixisis-sKhsftiHct,
one kind of connective tisane, can nerer be tr(insforni((l info onotlier
except throu<)1i the intermediate stage of medullary tissue. A com-
pletehj developed tissue must first return to the emhruonal condition,
before a new and diffirenf tissue ran develop from it.

Remak * was the first to ai)proa('h our present views respect-
ing: the formation of basis-substanee of cartibige. He maintained
that it is deposited between the outer and the inner membrane of
the cartihige-eell, whereupon the outer membrane perishes, and
the shells of the " parietal substance " fuse together in order to
form the intercellidar substance.

E. Briieke, t in accordance with the views held by Max
Schultze, considered the outermost layer of the cartilage cells,
destitute of a membrane, to be the former of basis-substance
proper. The layer close around the unchanged portion of the
cell-body he asserts to be more dense than the rest of the basis-
substance, and this condensation causes the appearance of a
capsule. Similar views are held by R. Heidenhain| concerning
the formation of single and stratified capsules. If these views
were correct in every respect, we ought to find in developing
cartilage enormous corpuscles, corresponding in size with the
whole territory, before the changes at theii' periphery had
ensued. But the facts are just the contrary to this, for in the
embryonal cartilage the corpuscles are decidedly smaller than in
that of the adult.

A. Spina § demonstrates that, in fully developed cartilage,
with advancing age the amount of basis-substance increases at
the expense of the cartilage corpuscles. These become pale,
finely granular, destitute of nuclei, and then disappear in the
basis-substance. The protoplasmic reticulum of the cells, he
says, does not perish, but remains, somewhat altered in its
character, in the l>asis-substance. This explains why, in the
articular cartilage of the very aged, the corpuscles are so
extremely scanty and small.

* Miiller's Archiv, 1852.

t " Die Elementarorganismen." Sitzungsber. d. Wiener Akaclemie d.
Wissensch., 18G1.

X Studien des Physiol. Instit. zu Breslau, 1863.

$ " Uutersuchungen iiber die Bildung der Knorpelgrundsubstanz."
Sitzungsber. d. Wiener Akademie d. Wissensch., 1880.

218 CONNECTIVE TISSUE.

I can fully (corroborate Spina's assertions from my own
observations.

(4) Bone Tissue.

Hintorij. The growth of the bones was the subject of careful studies in the
seventeenth and eighteenth centuries, long before anything positive was
known as to their structure. Adrianus Spigelius * was the first to maintain
that the bones gi'ow either fi-om cartilage or by apposition.

Clopton Havers t found that bone arises from cartilage.

Robei't Nesbitt t says that "there is not one single phenomenon to sup-
port the notion of bones being nothing but indiu'ated cartilage, or that they
are produced only by a transmutation of a cartilaginous substance, and all
bony productions are caused entirely by the apposition of cretaceous matter."

In the middle of the eighteenth century, Duhamel, ^ after experiments by
systematically feeding various animals with madder, asserted that the bones
grow from the periostemn, and was contradicted by A. Von Haller, who
denied any participation of the periosteum in the process. Exactly the same
fight is carried on even in our day.

John Hunter II found in the gi'owth of bones "two processes going on at
the same time, and assisting each other : the artei'ies bring the supplies to
the bone for its increase ; the absorbents at the same time are employed in
removing portions of the old bones, so as to give to the new the proper form.
By tliese means the bone becomes larger, without having any material change
produced in its external shape."

J. Howship U speaks of lining-membranes of the canals of the bone carry-
ing the blood-vessels ; he did not see the lining in full-grown bone, "possibly
because the circulation of the red blood is more limited in full-grown than in
young bone." He gives illustrations of lacunar widenings of the canals,
evidently caused by a morbid process.

After the bone-corpuscles (lacunae) and their canalieuli were made known
by Purkinje and Deutsch (1834), Johannes Midler' pointed out their con-
nection, and suggested that all these spaces are filled with lime, and should,
thei'efore, be termed canalieuli ehalicophori.

Lessing - first drew attention to the fact that the dark appearance of the
lacuna} and canalieuli, seen in specimens from (b-y bone, is due to their con-
taining air, and was inclined to regard them as a lacunar system, filled, in
living bones, with fluid. Klebs, much later, made the wonderful discovery
that the contents of these spaces in older, even fi-esh bones, are of a gaseous
nature.

*"De Formatioue Fcetu," 1631. Tlie early literatuie is found in Alb. Kiilliker: "Die
Nonnale Resorption des Knocliensewebes." Leipzig, 1873. Tlie later literature, from 1836 to
1878, is given by M. Kassowitz : " Die Norraale Gasification," etc. Wiener Meil. Jahrbiiclier,
1879.

t " Osteologia Nova ; or, Some New Observations in the Bonos." Loudon, 1691.

% Human O.steogeny, exi>lained in two lectures. London, 1731.

i " M6moircs de 1' Acad^niie do Paris." 1742.

II "Experiments and Observations on the Growth of Bone," fronj the p.apers of the late
Mr. Hunter, bj' Everard Home. London, 1798.

II " Microscojnc Observations on the Structure of Bone." Medico-Chirurgical Transac-
tions. London, 1816.

' Miiller's Arclilv, 1836.

2 " Ueber ein plasmatisches Oefass-System in alien Geweben, insbesonders in Knochen
und Zahueu." Hamburg, 1846.

COXXKCTIVK r ISSUE. 219

R. Virchow " claiined tliat tlio liM-iuiar aiul canalicular spacos aro really
plasmatic, and can be iwolatcd, as true "bone-cells," by the treatment of
dry bt)ne with acids. He was contradicted by E. Neumann,! who con-
clusively proved that Virchow's branching cells are nothing but the densific^d
walls of the lacuniu and the larger camiliculi resisting the action of strong
acids and alkalies (elastic substance). Such a substance was found to line
also the Haversian eaiuils,

A. Kollikert declared that on the external surfaces of gi-owing bones an
absorption takes place. Virchow, in l.S5;i,^ agi-eed that such an absorption
occurs on the cereV)ral surfaces of the skull-bones. Virchow had, in 1H5'2,
asserted that the bay-like excavations (so-called Howship's lacuuro) ou the
surface of pathological bones are due to a melting of the substance of the
bone, in correspondence with the cell territories ; afterward, he maintained
that the boue-ci'lls set free by the solution of the intercellular substance, are
transformed into medullary cells.

Tomes and I)e Morgan || observed erosions in carious and provisional teeth,
and argued in the following manner : " When we connect this condition with
the fact that the nucleated cells, which form the embryo, have the power of
appropriating tiie material which lies about them to the purjjose of their own
growth, ... it is difficult to resist the belief that the cells which lie in con-
tact with wasting bone and dentine take up those tissues. . . . An oV)jection
may be raised to the supposition that the bone is absorbed by cells, on the
ground of the density of the former ; but it must be borne in mind that, as
the density is gradually imparted to the bone through the agency of the
adjoining soft parts, tliere seems no good reason for disbelieving that they
may also be instrumental in its removal." If

Heiurich Miiller, in 1858,' published his epoch-making researches on
development of bone, which are the foundation of our modern views on this
subject. His observations will be dwelt upon in the article on development
of bone. Reference will there also be made to the researches of Gegenbaur
(ISGo) and Waldeyer (18G5).

Ed. Lang ^ was the first to ascertain that, in bone-specimens of recently
killed animals, the lacunas contain protoplasm, which is, to a certain degree,
endowed with the property of amoeboid motion, and from which starts the
inflammatory new formation.

In the last decennium, a lively controversy was carried on regarding the
question whether or not a gi-owth of the bone by expansion, a so-called inter-
stitial gi'owth, occurs.

Ruge,^ as the result of his counting and measuring the tlistances between
bone-corpuscles, became a defender of the theory of interstitial growth. Jul.
Wolff * energetically maintained an interstitial growth, and denied any appo-

* " Wiirzburger Verhandlungen," 1850.

t"Beitiage ziir Kenutniss ties uorra. ZiihuUcin- and Knocliengcwcbes." Koiiigsbeig,
18(i3.

t "Mikroskopisclie Anatoniie," 1850.

i!Vilcliow'8 Arcliiv, Bd. iv. 1852; Bd. v. 1853.

||"Obstivi>tic>iis on the Stiiicture and Development of Bone," 1852. I'hilosophical
Transactions, 1853.

i: All quotations from authors in this historical sketch are from KoUiker (I. c).

1 "Zeitsi'hrift fiir Wissensch.-Zoologle." Bd. ix.

2 " Unteisucliungen iibor die ersten Stadieu der Knoclienentziiudung." Wiener Mediz.
Jahrb., 1871.

s Virchow's Arcliiv. Bd. 49. 4 Virchow's Archiv. Bd. 50.

220 CONNECTIVE TISSUE.

sitioii from cartilage and periosteum. Lioberkiihn," on the contrary, fully
eori'oborated the old and well-estaldislied views of an apposition. Recently,
again, Strolzofft favored the view of an interstitial growth, and was con-
tradicted by Steudener, t w'ho demonstrated that the bone-corpuscles with
advancing age decrease somewhat in size, and consequently aj^pear to become
farther apart as the bulk of the basis-substance increases.

V. Ebner ^ has arrived at the conclusion, based on macerations of bone in a
ten to fifteen percent, solution of chloride of sodium, to which he added one to
three per cent, muriatic acid, that the lamellae of bone-tissue are composed of
fibrilla?. These fibers, according to him, can be isolated only for short distances,
as they are interwoven and held together by a cement-substance containing the
lime-salts, while the fibrillae themselves are glue-yielding, but destitute of
lime-salts. Fibers running fi-om a lamella to the surface of the bone consti-
tute the perforating fibers of Sharpey.

C. Langer || added valuable contributions to the knowledge of the distribu-
tion of blood-vessels in shaft and flat bones.

M. Kassowitz H published an extensive article on the formation of bone,
with special reference to the periosteal cartilage.

Methods. It is one of the strangest facts in histology that,
although for a number of years dry specimens of tissue have "been
acknowledged to be worthless for microscopical research, bone
even in our day is studied in the dry c<nidition. All books of all
nations on histology give accurate directions for slicing dry bone
and grinding the sections thin for mounting in Canada-balsam.
Such specimens are of little value for examinations with the
microscope. Specimens of dry bone are about as usefid for
obtaining histological facts as are the silver-stained specimens of
other tissues — L e., both exhibit the frame of the tissue, while
all the soft parts, the real seats of life, are destroyed.

There is but one way to render bone-tissue suitable for study,
and that is by softening fresh bone in a one-half per cent, solution
of chromic acid, to which from time to time very small quantities
of dilute hydrochlcjric acid may be added. If the chromic acid
solution be changed every fourth or fifth day, and if a large quan-
tity of the liquid be used for small pieces of bone, in a few weeks
the specimens can be easily cut with the razor. This method
was introduced by H. Miiller in 1858, but has been far too much

* Sitziuigsb. <1. Maiburger Gosellscli., 1872.

I Uiitersuclnuigeii aus clem ratliol. Inst, zii Ziiridi, 1S78.

f'Beitrage zur Lelire von d. Knochencntwicklnng." Abli. tier Xaturf. Ge.s. zu Halle,
1875.

5"Ueber den feineren Ban der Knochensubstanz." Sitzuiigsber. d. Wiener Akad. d.
Wissenscli., 1875.

||"Ueberdas Gefftss-System der Rolircnknoclien." Denkscliriftender Wiener Akademie
d. Wi.ssen.scli., 1875. " Ueber die BlutgefSsse der Kuoclieu des .Scliadeldaclies." Denksclilil-
ten d. Wiener Akadeniie der Wis.senscli., 1877.

II " Die Xomiale Ossification," etc. Wiener Mediz. Jalirbiiclier, 1879.

COXXh'CriVh' TISSUE. 221

n('<;ltM'tr(l. Tilt' l)('st sjxM'imcMs arc ohtaiiiiMl from ])()i*ti()tis in
which the hiisis-substaiict' is not entirely decalcified, as in these
the bone-eorpusdes and llicii- offshoots, as well as the corre-
spondinii' cavities in the basis-substance, the laenna' and canal-
ieuli, are l)est preserved. For inonntinj^, only dilute frlyccrine
should be used.

A nuin])er of examiners have attempted to settle the (luestiou
whether the lime-salts are de])()sited mechanically in the ])asis-
su])stance, or whether there is a chemical union of the molecules
of lime and jj^lue. The question probably will never be satisfac-
torily answered. This much is certain, that by the extraction of
the lime-salts by means of cliromic acid, no material changes are
produced in the giue-yielding basis-substance.

Boiie-corpifsdes. As eariy as in 1850, R. Virchow discovered
the identity of the "bone-cells" with other "connective-tissue
cells." Though he at first held the mistaken idea that the walls
of the cavities were the bone-cells proper, he admitted later
that the cavities, being hollow and filled with a liquid, hold
the bone-cells. He was the first who recognized them to be
the seats of life, and able to proliferate and produce meduUary
tissue.

As late as 1871, Ed. Lang, in Strieker's laboratory, recog-
nized the bone-corpuscles to be living matter or protoplasm in
the fresh condition, endowed \\dth the property of amoeboid
change. In this view the bone-tissue, as well as every other
variety of connective tissue, is built up by a calcified, glue-
yielding basis-substance, containing scattered cavities and outlets
of the cavities — the lacuna? and canaliculi of former hist ologists ;
the lacunie are filled with living matter, the bone-cells or bone-
coi-puscles. Nothing positive was known at that time as to the
contents of the canaliculi.

In 1872,* I undertook to stud}^ bone-tissue, both in fresh
and preserved specimens. In fi-esh sections, taken from the con-
dyle of the femur of young rabbits, transferred to the slide
together with a drop of a one-half per cent, solution of table-salt,
or, stiU better, of Mliller's liquid, with an immersion lens No. 10
of Hartnack, I recognized the bone-corpuscles. Thej^ were round
or oblong bodies of a grayish tint, Ij'ing in a shining l)asis-
substance, which appeared traversed by numerous light canals.

**'Studien am Kuoclieu und Kuorpel." Wiener Mediz. Jahrbiicher,
1872.

222 CONNECTIVE TISSUE.

In the bodies, whicli were indistinctly spotted, I could often see
a uiielens-like formation, with scalloped outlines. '' The ceU-
body," I said, " is surrounded by a light, narrow zone, in which
numerous conical offshoots are visible, emanating from the ceD-
body, and exhibiting the same character as tlie cell-body." In
many places I could trace these extremely delicate, branching
offshoots for a considerable distance in the basis-substance, and
saw them unite with the offshoots of neighboring coipuscles.
When the offshoots could not be followed far away from the
body, I found their continuations to be the light, branching
canals in the basis-substance.

The offshoots and their anastomoses I could see very plainly
in specimens stained with chloride of gold, where the dark violet
bone-corpuscles were seen sharply defined upon the pale violet
basis. The offshoots were likewise distinctly ^^sible in speci-
mens of bone, decalcified by lactic acid. With this method
the corpuscles seemed not to have shriveled, as the rim be-
tween them and the basis-substance was not broader than in
fresh specimens.

In specimens preserved in chromic acid, the bone-corpuscles
appeared somewhat shi'iveled. The basis-substanee inclosing their
cavity was traversed by numerous canals. Most of the offshoots
of the corpuscle resembled conical thorns, which terminated in
fine points toward the calibers of the canals, but only in a few of
these could I discern a granular substance which possessed the
characteristics of the corpuscle.

In normal bone, I was convinced that the bone-corpuscles had
offshoots which partly projected in the canaliculi, partly inoscu-
lated with each other. A plain view of these offshoots, however,
could be obtained only in bone, in which an inflammation had
been artificially induced. One of the first noticeable changes in
osteitis was the swelling of the corpuscle and the increased dis-
tinctness of its offshoots. These observations are illustrated on
page 126, Fig. 40.

In 1872 I was not aware of the significance of the union of the
bone-corpuscles, and it was not until a year later that I made use of
the structure of bone-tissue for pointing out new biological views.
I have been led, by careful researches of osteitis, to the conviction
that the basis-substance must be pervaded by a large amount of
living matter in reticular arrangement, which after liquefaction
of the basis-substance is freed and participates largely in the
inflammatory new formation. Direct proofs of the presence of

coNNKcTivr: TisscE. 22:5

this cxti't-mcly (Iclicatc n'ticiiliiin I could not obtain, as all ti'ials
with silver and <;()ld staining' of Ixtuc jji'ovcd to Ix' t"ailur<'s.

The boiie-eorpusclcs, as well as all other eonuective-tissue
eorpuselos, are formations of living matter, which in a juvenile
condition are found to be compact, homoj^eneous, or vacnioled
luni])s, while in full development they are nucleated ])lastids.
Tlu'ir shape varies, to some extent, with that of the territories of
basis-substance in which they exist. We find globular bone-
corpuscles, which have assumed a star-shape by the ai)pearance
of numerous radiating otl'shoots, in the earliest formations of
globular territories. We also meet with globular bone-corpuscles
at the peripheral portions of fully developed Haversian systems,
owing to the i)resence of the first formed territories of this sys-
tem, and again in the interstitial bone-tissue between the systems,
in places where no lamella? are formed. In striated or lameUated
bone-tissue the corpuscles are ol)long or spindle-shaped bodies,
slightly bent in the direction of the stria? or lamellne, intercon-
nected by larger otfshoots, emanating from both poles, and by
numerous delicate offshoots, traversing the basis-substance in a
rectangular direction. The latter offshoots arise at right angles
from both the periphery of the corpuscles and their larger longi-
tudinal branches. In the Haversian systems the bone-corpuscles
are slightly flattened, and in longitudinal sections exhibit their
broadest oblong surface whenever the razor strikes a peripheral
portion of a Haversian system, while they have the apjtearance of
narrow spindles, when the razor runs through the middle of a
lamellated system. In transverse sections of the system the
corpuscles exliibit irregular shapes, and again vary in their diam-
eters according to the depth to which they are cut by the razor.
A spindle will necessarily look broader if the section has been
made transversely through the middle, and narrow if near the
ends.

Varieties of Bone-tissue. There are two kinds of bone-tissue,
which, in the fully developed subject, however, are always com-
bined with each other, viz. : the cancellous, epiphyseal, or spongy
bone-tissue, and the compact or cortical bone-tissue.

(a) Cancellous., Epiphyseal^ or Spouf/ij Bone-tissue is built
up by trabecnlae, arranged as a frame-work inclosing the medul-
lary spaces. It is the only kind found in early stages of develop-
ment of bone. In the foui'th, fifth, and sixth months of
embryonal life of human beings, and in dogs, cats, and rabbits
at birth, no other bone-tissue but the cancellous is found. In

224

CONNECTIVE TISSUE.

the juvenile skeleton, this structure composes the epiphyseal
ends and the central portions of the shaft-bones, and the central
portions of flat and short bones. (See Fig. 86.)

Cancellous bone-tissue of the embryo is invariably striated
and non-lamellated. In the fully developed skeleton it exhibits
usually indistinct laniell*. The spaces between the trabeculae
of cancellous bone are in youth filled with a richly vascular-
ized medullary tissue, the "red medulla" of Virchow ; while with

YiG. 86. — Tibia of a Newly Born Pup. Longitudinal Section.
Chromic Acid Specimen. [Published in 1873.]

T, trabeeuliE of boue-tissue containing bone corpuscles; .1/, nieilullary spaces filled
■with me(Uillary tissue, holding blood-vessels in tlie most central poitions. Magnified 200
diameters.

advancing age the spaces exhibit fat-tissue, Virchow's "yellow
medulla."

In very old persons there is an increasing deficiency of both
the cancellous and compact bone-tissues ; the bone corpuscles are
also very small and few in number, as many of them have been
transformed into basis-substance.

The relation between the cancellous and the compact structure
differs in different bones. As a rule, the short bones are largely

COXXECTIVI'. J/SSIK. 22;')

made up of cancellous tissue, with only a tliin layer of eonipaet
hone at their ]>eri])heri<'s. Fhit hones exliil)it the enneellous
structure in the iniihlle portion, the (iipjoi' of skull-bones,
wliile the layers on the outer and inner surfa(;e an* formed
entii-ely of eoin])a('t bone, the outer layer beinji^ f^enerally
broader Mild i-iciiei- in blood-Ncssels than tlie inner. Thin, small,
flat bones, such as the ethinoideal, tur])inate, etc., may l)e ecm-
sidered as tlattened trabeeuhe of the caneellous variety. The
shaft-bones have a broad investment of compact structure in
theii- middle, /. c, diaphyseal portion, while this tissue gradually
decreases toward the ends, the epiphyses. These parts, as well
as the larji'e central marrow space, exhibit the caneellous struct-
ure ill greatly varying amounts. H. Meyer first drew atten-
tion to the fact that the trabeculse of the cancellous structure,
especially in the epiphyseal extremities of shaft-bones, were built
up according to a cert.iin law, and J. Wolif, with the assistance
of Ciilmann, has explained, according to mathematical principles,
the regular arrangement of the trabeculae in the dii-ections of
lines of pressure and traction.

fbj CorUral or Compact Bone-tissue is composed of parallel
lamellae, closely packed together in intimate relation with the
blood-vessels. The cortex of both flat and shaft bones ('onsists of
a concentric system of lamellae surrounding the central mari'ow
space, and this concentric system in its middle portion is trav-
ersed, usually at right angles, by a number of systems of lamellae,
each surrounding a central lilood-vessel. Thus, two peripheral
systems of lamelhie originate, of which the outer is always the
broader, and well marked, the inner often but little developed.

The middle portion, lying between the two peripheral sys-
tems, is traversed more or less rectangularly by the Haversian
systems. In transverse sections of the cortex of shaft-bones, the
lamellae of the two peripheral systems run longitudinally, while
the Haversian systems are cut transversely or obliquely. Be-
tween the latter there are the longitudinal lamella? of the so-called
" interstitial or intermediate '' bone-tissue. (See Fig. 87.)

The Haversian system is composed of lamellae which are dis-
posed in concentric layers around capillary blood-vessels. Such
systems of lamella? are regidarly arranged in the cortex of the
long bones, and irregularly in the cortex of flat bones. The outer
contour of a system is never smooth and even, but composed of
a number of shallow protrusions, viz., the fii"st-formed territories,
and the aggregation of these formations gives the outer contour
15

226

CONNECTI ^ E TISS VE.

of a Haversian system a fluted appearance. The systems are
sometimes found close to each other, with very little inter-
mediate Tjone-tissue between them; or they may be more or
less apart, with a distinctly lamellated intermediate bone-tissue

4

6

* '/
' if-

^ ^i

?;.i

\

It* '

t- ^^i .?^ ^x^%>-"'-

.. 1 ' • .

". 2 S.

\.

.N""^

between them, the lamella of which run in a direction more or
less parallel with the peripheral lamella?. This probably depends
upon the original distribution of the blood-vessels, which, if rami-

COSNF.CTIVl': TissrK

227

fvinj^ at very Jiciitc aiifilt's, will nmkc their systems of laniellM' lio
dose to»:;ether ; but if raiMifyin<;" at less aeute aiif^les, will leaver in-
terstices filled with (listiiu'tly lamellated intennediate bone-tissue.
In order to render the formation of cortical bone easily understood,
the followiuii' illustration is often used: take a number of nnitches,
around each of which is twined a cord, and wind the cord around
the bundle, tlio nuitch representinji: the Haversian canal, the twines
around t'acli nuitch the systems of lamelhv, and the twines around
the bundle the peripheral lanielhe. This coiu})arison holds ^-ood,
of (rourse, only for the case in which the intermediate l)one-tissue
is absent. The law, however, according to which the peripheral

^^A7yMMWi:^--:J^r^^X,. ''

, ■^r;;j^ I

^.

y-y/.

■~-j: !

'^^rS&^i^m0ynf^^

Fig. S.S. — Tibia of a Grown Dog. Cortical Portion, Transverse
Section. Chromic Acid Specimen.

.V, Havei'siau system of lamellap, coiitainiug the bone-corpuscles, r, witli their radiating
offshoots ; J/, central medullary, so-called Haversian canal, containing a capillar}- blood-
vessel ; /, interstitial bone-tissue indistinctly lamellated. ilagnitied 500 diameters.

and the Haversian systems of lamellae are formed, has not yet
been explained.

With higher amplifications of the microscope each Haversian
system proves to be composed of a number of concentric lamella^,
which are not perfect throughout the S3^stem. Both ^^itllin and
between the lamellae, bone-corpuscles are visible with radiating
offshoots, a number of which traverse the lamellge, without being
in dii-ect connection with a bone-corpuscle. (See Fig. 88.)

228 CONNECTIVE TISSUE.

The center of the Haversian system is pierced by the medul-
lary or vas(nilar canal, which is of a varying caliber, according to
the age of the individual, and contains, besides a certain number
of medullary corpuscles, one or two central capillary blood-
vessels. Whenever the extremity of the animal from which the
shaft-bone was taken had been in a pendent position after death,
the vessels are found tilled with l)lood-corpuscles.

Longitudinal Sections are easily understood after the study of
transverse sections. Here, too, the Haversian system is bordered
by a fluting contour, due to the presence of globular tenitories of
an early formation, and l)etween the systems we find the inter-
mediate bone-tissue, which in this situation, as a matter of
course, will not exhibit lamination. In the intermediate portion
we find the bone-corpuscles cut transversely, \vith most of their
offshoots cut either obliquely or transversely, the latter being
represented by a number of delicate dots.

In the Haversian system the lameUiie take a longitudinal
coiu-se ; within and between them are found the spindle-shaped
bone-corpuscles, exhibiting, for reasons explained before, the
greater bulk the nearer the periphery of the system. The off-
shoots of the bone-corpuscles emanating fi-om their periphery, as
weU as from theii- polar projections, pierce the lamellt^ at right
angles. The central canal contains a varjdng number of medul-
lary corpuscles, and in its middle one or two straight capillaries.
Even with moderate powers of the microscope delicate filaments
are recognizable, l)y which the (jff shoots of the bone-ccn-puscles
connect with the medullary corpuscles, and the latter with the
endothelial wall of the blood-vessel. (See Fig. 89.)

Periosteum. The investing fibrous connective-tissue layer of
all bones, the periosteum as weU as the cartilage, takes consid-
erable part in the development of the osseous system. In human
embryos of four to six months, the outermost layer of the peri-
osteum consists of l)undles of fibrous connective tissue, and
between this layer and the cancellous bone there is a broad layer
of medullary corpuscles, in continuity with the medullary forma-
tion in the spaces of the bone-tissue. "Prom the outer fibrous
portion of the periosteum oblique Imndles of considerable density
are seen to pass into the medullary spaces of the bone, and these
bundles remain unchanged even after the compact portions of
the bone have attained fuU development. Such bundles, faintly
visible in chromic acid specimens, are termed " perforating or
Sharpey's fibers" (described by Sharpey in 185G, l)ut previously

COSSHCI IVF. 11 SSI- 1-:.

229

))y Trojii, ill 1S14). They tmviM'se the outer jxTiphcral system
«)f lanu'lliv, soinctiines in the form of siiij^lc cords, sometimes as
a broad reticulum, hut often they are entirely absent.

Fig. Si).— Tibia of a Grown Dog. Cortical Portion, LoNiJiTUDiNAL
Section. Chromic Acid Specimen.

S, HiiviTsiau system of lamellii', coiitaiuiufi: the bone-corpuscles, C. with their transverBC
offshoots ; M, ceutral meilallarj-, so-called Haversiau canal, containing a capillary blood,
vessel; /, interstitial bone-tissue. Magnitied 500 diameters.

In fnlly developed bone the periosteum consists of two layers,
the outer fibrous portion lieing supplied with numerous blood-
vessels, which inosculate directly with the blood-vessels of the

230 CONNECTIVE TISSUE.

bone-tissue, while the innermost portion, closely attached to the
surface of the hone, is a dense ribboned layer, with a scanty
supply of blood-vessels, but rich in elastic substance. This layer
is often the seat of calcareous deposition, and owing to this fact
its plastids assume iiTegular, jagged contoiu-s similar to those of
bone-corpuscles. The calcified periosteum, however, is not true
lamellated bone. It is often described under the name of the
" osteoid layer.'"' The periosteum is very thick at the points of
the attachment of tendons and ligaments. The inner surface
of the flat skull-bones, after the fifth or sixth year of life, is
destitute of a periosteal investment proper. This can be clearly
understood by the study of the development of these bones.

Blood-vessels. The bone-tissue, its investment, — the perios-
teum,— and its contents, — the medulla, — are plentifully supplied
with blood-vessels. They enter the periosteum mainly at the
points of attachment of the large ligamentous formations men-
tioned above. Arteries and veins are most abundant in the
outermost portion of the periosteum, where extensive ramifica-
tion of these vessels takes place. The arterioles enter the larger
canals at the siu'face of the bones and branch into capillaries,
which unite to form the efferent veins accompanying the arteri-
oles. At the inner surface of the compact bone, also, there is a
free anastomosis with the capillaries of the medulla. The
medulla is supplied "svith numerous capillaries, arising from the
so-called nutrient arteries of the bone, which pierce the corti(!al
substance obliquely and split at acute angles, both within the
canal and after entering the medulla. The veins collect the
blood from tassel-like bundles of capillaries and accompany the
afferent arteries. The epiphyseal portions of shaft-bones, besides
the general medullary vessels, receive blood from the vessels
which supply the articulations. The capillaries terminate, in the
shape of loops, close below the articular cartilage. The veins in
the bone-tissue are \rithout valves, but as soon as they reach the
surface of the bone, we find valves are present (C. Langer).

Lymphatics are not yet known to exist in the bone-tissue.

Xerves, both of the meduUated and non-medullated variety,
accompany the larger blood-vessels, but they are not abundant
in the bone-tissue. In different places in the periosteum, Pacin-
ian coii^uscles are found.

The medulla of the bone is, in juvenile condition, a myx-
omatous tissue, at first of the medullary, later of the reticular
variety (see pages 147 and 148). and, being freely vascularized, is

coxsF.crivE rissri':.

231

tcriiicd " /77/ ))i((liillii." With adviiiiciii^ )»<;•(' tlic iiicdulla is
uliuost I'litiirly tninsfonncd into fut-tissuc, wliilc tln' 1»1<mm1-
vessels decrease in number on aeeoimt of the hirj^c pioixn-tion
of fiit; it is then terjiied the '' ijclhur incdiillti.'^

The Relation of the Systems of LA:vn:LL>i-: to
THE Blood-vessels.*

Tlie eortieal substance of the shaft-bones of a newly born
pup is composed of trabeculae, which form a reticulum, elon-
pited ill tlie loiiiiitudinal axis of the bone, the meshes beings the
medullai-y spaces. Tlie width of a trabecula is about the same
as the diameter of a neighboring- medullary space. The tral)e(;u-
IsB are bone-tissue of a striated appearance, and contain flat
bone-corpuscles in a concentric arrangement. In the medullary
spaces we find the glol)ular elements of the medulla closely
packed together with ramifying blood-vessels, principally in the
center. (See Fig. 90, and also Fig. 86.)

Fig. do.— Tibia of a New-eorx Dog. Transverse Section.
Chromic Acid Specimen.

P, fibrous portion of tlio periostt'iim: .V-V, subperiosteal medullary layer; T. trabecula
of bone ; M, medullary spaces. Magiiitied 25 diameters.

In the compact substance of the bone of a dog about six
months old, the bulk of bone-tissue several times exceeds that of
the medullary tissue. We stiU meet with medullary spaces con-
taining blood-vessels and globular elements. Far more numer-

* Translated from " Ueber die Rik-k- uiid Neubildung von Blutgefassen im
Knochen und Kiiorpel." Wiener Mediz. Jahrb., 1873.

232 CONNECTIVE TISSUE.

ous than niedulhiry spaces, however, are the so-called ''vascular
canals " — /. e., cylindrical or oval tubes, with one or two much
elongated blood-vessels, and oblong or spindle-shaped medidlarj'-
corpuscles. The larger the diameter of a medullary space or a
vascular canal, the narrower, as a rule, is the surrounding bony
layer; the broadest layers of lamellae correspond to the narrow-
est vascular canals. The blood-vessels of the medullary spaces
anastomose with those of the vascular canals by means of trans-
verse and oblique branches; the vessels of the canals anastomose
with each other, and with every vessel we find a varying thick-
ness of lamellae. (See Fig. 91.)

In the diaphysis of the tibia of a dog a little over a year old,
the area of the bone-tissue surpasses that of the vascular canals, in

J,

:^

'''■^r^ ¥ hij^^r^^mm^^^^mMAMW^'

Fig. 91.— Tibia of a Dog, Six Months Old. Transverse Sectiox.
Chromic Acid Specimen.

M, medullary space, with a relative!}- small amount of surroundinff lamclla3 ; -S'l, narrow
system of lamella; around a medullary space : .S'J, broader system around a vascular canal.
Between the systems is the lamellated intermediate bone-tissue. Magnified 200 diameters.

a linear, direction, six to eight times. In the compact bone, larger
medullary spaces are found only in the vicinity of the central
marrow-canal. The vascular canals are surrounded by broad
systems of lamellae, containing the bone-corpuscles in a concen-
tric arrangement. Sometimes we meet, in transverse sections,
with two smaller systems, each with a central canal, the two
encircled by a common layer of an hour-glass shape. The inter-
stices between the systems are filled by a non-lamellated bone-
tissue, whose corpuscles are somewhat larger than those of the
lamellae, and irregularly distributed. The territories of such cor-

( (Lwxh'cn 1 'y<; tissuk.

233

pusclcs arc soinctimcs sliiir])ly iiiiirkcd. Into tlu* iiit(*riii('(liat(!
boiu'-tissue wo can also trace vasciilai- canals — the lateral
branches of the longitudinal vessels of the compact bone.

In the ti])ia of a (l()i>- several years old, the area of the bone-
tissue surpasses that of the vascular canals by twelve or fifteen
linear diameters. Larjje medullary spaces are found only near
the central marrow-tube, while the rest of the cortex exhibits
vascular canals of varying- calibers, the larger of which contain
some reticular connective tissue aud fat-globules around the
vessel. The parallel systems of lamella? belong either to a single
vascular canal or to tw^o or three narrower systems which are
surrounded by a large comnu)n system. The intermediate tissue
is usually lanu'llated ; in porti(ms where lamella? are wanting,
semicircular or circular contours of territories are found surround-

FiG. 92.— Tibia of a Dog, Ten Years Old. Transverse Section.
Chromic Acid Specimen.

S, system of himelliu with a central vascular canal; O, system of lamella' with a central
bone-coriniscle ; /, intermediate lamellateil bone-tissue. Magnified ;200 diameters.

ing small, bay-like spaces. Not infrequently we meet with sys-
tems of lamella^, the centers of w^hich are not occupied by a vas-
cular canal, but' by a bone-corpuscle.

Similar conditions are found in the tibia of a dog eight to
ten years old, although the solid systems of lamellae are stiU more
numerous. The central marrow^-tube is inclosed by a common
lamellated bone-layer, while the layer between the periosteum
and the bone is lamellated only in part. (See Fig. 92.)

The femur of the same animal is encircled bv a broad, lamel-

234 CONNECTIVE TISSUE.

lated layer boneath the periosteum, as well as at the T)()rder of
the eentral iHarrow-tul)e. Where these layers are pierced by
vertical vascular canals, such canals, as a rule, are surrounded
by more or less perfect sheaths of lamellae.

From these observations it follows tliat, independently of the
general growth of the bone, the li\dng matter stored up in
the medullary spaces is the forming- material of bone. The ele-
ments termed '' medullary cells," as well as "• osteoblasts," are
transformed into bone-tissue, and in this way the lamellated
layers of the bone become broader, and the medullary spaces, on
the contrary, narrower. The systems produced by the contents
of a medullary space surround smaller systems, the formation
of which depends upon the single blood-vessels of the f(n*mer
medullary space, which now occupy the centers of the vascular
canals.

All systems of lamella?, therefore, are vascular territories, — as
it were, stratified pillars, — the main longitudinal direction of
which agrees with the course of the blood-vessels in their centers.
From the main longitudinal course of this structure, branch sys-
tems, frequently in the ol)lique, rarely in the transverse, direction.
The formati(m of non-lamellated intermediate bone-tissue also
depends upon the blood-vessels.

Watching the contents of the vascular canals with high ampli-
fications, I observed the following features :

In the bone of a dog about six months old, each vascular
canal contains one or two blood-vessels, of varying caliber and
of a straight course. I have several times seen nerves running
along with the vessels, though my method of preparation was
not favorable to the clearing uj) of nerve-tissue. The wall of the
blood-vessel, as a rule, exhibits the simple structure of a capillaiy,
with occasional spindle-shaped thickenings. The vessel is sur-
rounded by a light rim, traversed l)y delicate gTajish spokes,
connecting the wall of the vessel with the neighboring spindle-
shaped elements. The latter ensheath the perivascular space,
either in a single flat layer or in several strata, and are also inter-
connected by short projections. Between the spindles and the
bone-wall there is again a light rim, traversed l)y delicate off-
shoots, which directly connect the spindles with the offshoots of
the bone-corpuscles.

In the tibia of a dog over a year old, I found similar vascular
canals ; besides numerous canals which, sometimes in places and
sometimes in their whole length, contained only a capiUary

L'osxKcriM': rissih'.

235

vessel. I met witli this arnui^ci
animals. Between the wall of

-P

Fig. 9;^. — Horizontal Section
OP THE Scapula of a Grown
Dog. Specimen Decalcified
with fi'rolignic acid. [pub-
lished in 1873.]

C, capiUary blooil-vessel, containing a
single row of red blood-corpuscles, the
vessel pointed and solidified ; P, elongated
medullary corpuscle, jxnd B, bone-corpus-
cle, both sprung from the solidified blood-
vessel. Magnitieil SOO diameters.

iieiit most fre(in<'iitly in the older
the vessel and that of the bone
there is always a light, narrow
rim, ci'ossed l)y ])roje('tioiis of the
nei<;hl)oriii«;l)(nie-('or{)ns('les, unit-
ing: with the wall of the blood-
vessel. The rim is absent only
when the blood-vessel is overfilled
with an injection mass.

In the eomj)aet portion of
shaft-bones and scapula^ of dogs,
eats, and ral)bits of middle or old
age, I often encountered vascular
canals, which were either con-
stricted in an hour-glass shape
or terminated in points. This
condition was positively recog-
nizable by the fact that, above
and below the vascular canal,
layers of bone-tissue (respectively
bone-corpnscles) could be brought
into focus. Closer examination of
such vascular canals in longitud-
inal sections, as a rule, revealed
the presence of but one blood-
vessel. (See Fig. 93.)

Toward the pointed end the
wall of the vessel became thick-
ened, as if composed of spindle-
shaped corpuscles, between which
the caliber either narrowed sud-
denly or gradually, terminating
close to a spindle-shaped body.
In the caliber of the vessel red
blood-corpuscles were occasion-
ally present, and I repeatedly saw
the injected mass penetrating the
pointed end. The corpuscle which
occluded the fine point of the ves-
sel proved to be a bone-(n>i'j)uscle.
and in the direction of the vessel,
at intervals, similar formations

236

CONNECTIVE TISSUE.

were visible, separated from each othei- \>y finely granular or
honiog-eneous shining- masses.

The same condition was also observed in transverse sections.
I found in the center of a system of lamella solid, finely granular
corpuscles, which, in both an upward and downward direction,
blended with the transvei-se cavities of bone or with the calibers
of vessels. (See Fig. 94.)

The conclusions I arrived at are as follows: The material
contained in the vascular canals is, with advancing growth,
transformed into bone, leaving only the blood-vessel behind.

Fig. 94. — Transverse Section of the Injected Tibia of a Grown Dog.
Chromic Acid Specimen. A Common System op Lamella Incloses
Two Smaller Systems. [Published in 1873.]

BY, the central vascular canal, with a capillary blood-vessel; -BC, a central solid coriniscle
sprmic: from a former blood-vessel. Magnified 800 diameters.

After a time, a transformation of the blood-vessels themselves to
bone-tissue takes j)lace by a solidification of the hollow proto-
plasma of the wall of the vessels, and thereupon a differentia-
tion into bone-corpuscles and bony basis-substance.

Development of Bone.

It is a fact, well known for centuries, that the skeleton in the
embryo is first formed of cartilage. The main question at all

coNNKcnvh: tjssij<:. 2:{7

times luis been : How dovs Ixmc arise from I'jirtila^'c ? A satis-
factorv aiiswci' to this (lucstion was impossil)l(' so loiij; as tlic
minute structure of cartilage was unknown, and, indeed, a fnll
understaiidiiii;' of the process of ossification is of a wry recent
(Lite.

Throuiih the researeiu's of Ratlike, Keiehert, Kolliker, and
others, we know that there are l)ones which do not develop from
cartilage, but from fibrous connective tissue, formerly thought
to be a "blastenni.'' All bones of the skeleton arise from pre-
existing cartilage, except the tiat skull-bones — viz.: the squam-
ous portion of the occipital and temporal bones, the parietal,
frontal, and ])ortions of the sphenoid bone, and the nasal,
lachrymal, vomer, malar, palatine, and upper maxillary bones.
The clavicle was in former times thought to be destitute of a
(cartilaginous basis, but recently it was found to be cartilaginous,
at least at its extremities (M. Kassowdtz). There is, however, a
great similarity between the fornuxtion of the so-called " carti-
laginous" bones and that of bones termed " covering." In all
cartilaginous bones the formation of bone proceeds simidtane-
ously both from the cartilage and from the perichondrium, the
fibrous investing niembi'ane.

The ossification of cartilage was first studied. In former
times it was believed that, by the deposition of lime-salts, the
cartilage was directly transformed into bone — the "cartilage
cells '' dii'ectly converted into " bone-cells." Observers were
much puzzled over the formation of the " canaliculi," and Kol-
liker, in 18.12, inuigined that he had settled the matter by assum-
ing that the cartilage-cells were transformed into bone-cells
by a thickening of their walls, with a simultaneous formation of
canalicidi, similar to the pore-canals of "wood-cells" of plants.

A new era was inaugurated in 1858 by H. Miiller, * who, after
very careful researches, came to tlie conclusion that the cartilage
first breaks down into medullary tissue, and from this tissue bone
is developed. H. Miiller, howevei-, admitted that a direct ossifi-
cation of cartilage (metaplasia of authors) may also occur.
Although he was ignorant of the fact that the whole medullary
tissue giving rise to bone is an offspring of cartilage, the great
merits of this accurate observer must always be recognized.
To-dmj ivc hnoir that a direct transfovmation of cartilage or fibrous

* " Ueber die Entwicklung der Knocheiisubstanz, iiebst Bemerkiuigeii
iiber den Ban rachitiseher Kuoclien." Zeitschr. f. Wissenscb. Zoologie.
Bd. ix.

238 ( OXXECTI 1 7-; TTSSUE.

tissue into hone uerer occurs ; fhat between, these two hinds of com-
pleted tissues the intermediate medullary, or emhryonal tissue, stage
is inrariahhj present.

For the study of this highly interesting question the best subjects are the
bones of human embrj'os, between the fourth and seventh months of intra-
utemie life, or the eoiTespondingly developed bones of newly born pups or kit-
tens. These animals, at the time of birth, are, as I have already stated,
advanced in development as far as human beings in the middle of intra-
uterine life. Dogs and cats one year of age correspond in development of
this tissue to human beings in the twentieth year of life, and dogs and eats
ten to twelve years old are as far advanced in tliis regard as men of sixty
years.

The phases of development of bone can, of course, be studied with
gi'eater ease in dogs than in human beings, and a number of facts obtained
from the bones of animals have not as yet been established by investiga-
tion of human bones. All specimens must be preserved in, and partly or
wholly decalcified by, a one-half per cent, solution of chi-omic acid; many
of the blunders of former histologists, regarding development of bone, re-
STilted fi'oni the examination of dry specimens.

Development of Bone from Cartilage.

Ill sagittal (autero-posterior) sections of shaft-bones of a
hnman eniljryo, about five months old, we see that both ends
of the future bone are composed of hyaline cartilage, containing
many medullary spaces. With low powers of the microscope
we recognize that the cartilage corpuscles are closely packed
together in the outermost portions of the roimded extremities ;
next, the corimscles are less crowded, but arranged, at regular
intervals, in giol)ular heaps, and gradually become arranged in
rows, as the cartilaginous head slopes toward the middle portion,
the future shaft. It is a mistake to suppose that these changes
of shape and situation of the cartilage corpuscles are due to their
own activity — that, as Virchow has expressed it, the corpuscles
'' direct themselves into rows." Before the third month of em-
bryonal life we can easily ascertain the fact that, from the earli-
est stages of formation of cartilage, the rows are present in the
middle portion. It is impossible to understand how cartilage
corpuscles, being imbedded in a dense and tough l)asis-substance,
could perform active locomotions without the basis-substance
having been previously liquefied.

(aj Calcification. At a certain point, nearer the middle, in
the younger embryo, the basis-substance is found to be the seat

coxMnrivi-: nssri:.

239

(liiVrn-iit liiiiiinii

!■ *^csS9 •

.f-:::

,^.

4fla^5 — — t'

of a calcareous deposition. This occurs first in the middle of
the sh.-ift, and gradually proecM-ds toward both exti-einities, varv-
inj^ coiisideralily, l)oth in time and cxtciil, in
eniltrvos and inditt'erent ani-
mal embryos. In specimens
decalcified by chromic acid,
the basis-snbstance, which
was the seat of a deposition
of lime-salts, readily takes
up the carmine stain. (See
Fi- 9.-,.)

The calcareous deposition
occurs only in the broad
masses of basis-substance be-
tween the territories of the
cartilage corpuscles, in con-
seiiuence of which an elon-
gated reticular frame is visi-
ble, which at fii-st surrounds
the territories of the cartilage
corpuscles, and deeper l)elow,
in a nearly level line, it sur-
rounds the spaces filled with
medullary corpuscles. The
calcificaticm is shai-ply de-
fined by pointed ends toward
the unchanged cartilaginous
portion. In the deeper por-
tions of the calcified frame
the first traces of newly
formed bone-tissue are no-
ticeable in the shape of
bright crcifcentic fields, at-
tached by their convex sur-
faces to the calcified frame.
This investment of bone soon
produces a continuous layer
around the frame at its bor-
ders toward the medullary
spaces.

In the cartilaginous heads
of shaft-bones of human embryos, at a somewhat later ])eriod, a

Fju. 95. — HuMERrs of a Human Em-
bryo, Five Months Old. Sagittal
Section. Chromic Acin Specimen.

(\ rows of cartilage corpuscles iu elongated
groups, due to their territories ; /', frame of calci-
ned basis-substance, around wliicli, in the lower
portions, the first traces of boue-tissue arc no-
ticeable; Jl/, medullary space, containing medul-
lary corpuscles. Magnified 300 diameters.

240

CONNECTI VK TIHSUE.

deposition of lime-salts starts from the center of each head, inde-
pendently of the calcified shaft. The frame of calcified basis-
substance in this sitnation is of a roundish form, agreeing with
the general shape of the cartilaginous head. In some cartilagi-

?.A\T'*^/-

Vfl ''(coi

> 32

S 2

^5

>

^ fe

3 a-

S s

S .2

- = «

ft, «

nous heads of long Ijones, the calcification ocinirs at a very early
period, f. i., in the vertebral ends of ribs ; while in short bones
the calcification, always starting from the center of the pre-

CONNECTIVE TISSUE.

241

formed cartilaj^o, is of a lator date ; f. i., in the vertebra?. (See
Fiii-. 9(1.)

In ue\v-l>oni pups, kittens, and riil)l)its these features are
very similar, thoufjjh sometimes the caleification precedin<i^ the
ossifieatiou is wantin«i^, even in shaft-bones (see, f. i., Fig. 98).
It is wantintj, as a rule, at the cartilaginous border of the plate
of the s('a])ul;i.

Fig. 97. — Vertebral Extremity of the Rib of a Human Embryo, Ten
Weeks Old. Horizontal Section. Chromic Acid Specimen.

H, liyaline cartilaRe, with mostlj' multiple formations of corpuscles in the territoiics;
C, calcilietl frame of basis-siihstance; P, cartilage corpuscles CitU jaggetl offshoots, enlarged
l»i' li(iuefaction of the basis-substance. Maguitietl 500 diameters.

We know that the calcification of cartilage is the first step in
the development of l)one, and as this process takes place inde-
pendently in three portions of the shaft-bones, three nuclei of
16

242 COyXECTlVE TISSUE.

bony tissue are formed — one in each epiphysis and one in the
diaphysis. The outer portion of the epii)hyseal cartilage is the
articular cartilage proper; the cartilaginous portion between
the epiphysis and the diaphysis is termed the dia])hyseal or
intermediate cartilage, which in human beings completely disap-
pears about the twentieth year of life.

(h) Formaiion of Merltillarij Tissue. The cartilage eoi"puscles
close above the place of calcification always have a coarse gran-
ular appearance, and are without a distinct nucleus. "We under-
stand from this that the bioplasson of the corjmscle has increased
in amount, and thus begins a retrogression toward the juvenile
condition. In the spaces surrounded by calcified Ijasis-substance
the cartilage corpuscles assume a very coarse gi-anidation ; many
of them are nearly homogeneous, have a bright and vacuoled
appearance, and are furthermore marked by radiating offshoots.
(See Fig. 97.)

At the same time the cai'tilage corpuscles increase in bulk,
also, by the addition of li^-ing matter, which, after the liquefac-
tion of the basis-substance, simply re-appears fi-om where it before
was concealed. This re-appeavance of li\"iug matter is indicated
first by a somewhat coarser granulation of the basis-substance,
and subsequently by the formation of new lines of demarkation,
corresponding to the liquefied i)ortion of the basis-substance.
Even with moderate powers of the microscope all stages of the
re-appearance of bioplasson are traceable, from a distinct granu-
lation of the basis-substance up to the formation of fields exhib-
iting the features which in former times were termed '' pale
protoplasm." Such fields either suiTOuud the original cartilage
corpuscle, or are joined to a part of the corpuscle. If the razor
has struck the peripheral portions in a space suiTOunded by the
calcified frame, only pale granular bioplasson is visible, and
there will be seen basis-substance alone if the section reached
the outermost portion.

The next stage is the splitting of the biojjlasson masses into
numerous smaller indifferent — /. e., embrv(jnal or medullary —
corpuscles, each of which assumes a coarse granulation. It is
obvioiis that at fi^rst only those embryonal corpuscles will appear
which once themseh-ls took part in the formation of the terri-
tory. By an increase of the l)ulk of their bi()i)lasson these cor-
puscles become nucleated, and at first are finely, and later
coarsely, gi-anular. Small lumps of bioplasson may also show
themselves, of a homogeneous appearance, a high degree of luster,

CONNKcriVh: TISSUE. 2A'.\

and ii distinct yellow color. This indicates .i new I'cu'niation of
livinu: matter. In 1S7L', I named these solid Inmps " lui'iimto-
blastic" (see i)a<j:e 98), as I had observed the new formation of
red l>lood-e()r])uscles arisin<r from them. In 1873, I proved this
condition to be the juvenile state of livin<i- matter in general
(see pa«re 51 ).

H. Miiller asserted that many of the medullary corpuscles are
the productions of the oriji'inal cartilage corpuscles, and in this
he was (piite correct. But later ol)servers, their uuml)er unfort-
luiately being- great, have disposed of the cartilage corpuscles by
saying that they fade and perish, and that all medullary cor-
puscles are "leukocytes" — colorl&ss blood-corpuscles, which have
migrated from the blood-vessels of the medullary spaces, or of the
perichondi'ium, through the cartilage and into the medullary
spaces. There is no ground whatever for such assertions. To
assume that leukocytes migrate through newly formed blood-
vessels, which are not yet iu connection even with the old vascu-
lar system, sounds whimsical enough. Further to insist, however,
that leukocytes creep through the dense and unyielding basis-
substance (for, at that time, nothing was known of '' juice-
canals"), is simpW an al)surdity. These hypotheses fall to the
ground when we know that the basis-substance contains a large
amount of living matter ; that a liquefaction only of this basis-
substance is recjuired to free the bioplasson, from which, by its
rapid growth and Ijy the splitting of its lumps, new medidlary
corpuscles arise. The process, in short, is : re-appearance., tUnsion,
and ncir fhrinafinn of hiopJa^son.

That i-eally the whole medullary tissue, filling the space
inclosed by a calcified frame, is a production of both the car-
tilage corpuscles and the living matter in the surrounding
basis-substance, is best illustrated by specimens where, with-
out a jjreliminary deposition of lime-salts, the territories of
cartilage tissue are immediately followed by medullary spaces.
(See Fig. 98.)

Here we see, in certain territories of the cartilage, masses of
medullary corpuscles in no way connected with the medullary
spaces below. The spaces are exactly in a line with the terri-
tories directly above, and are filled with bioplasson lumi)S in all
stages of development. (See page 46.) The centers of the nuisses
exhibit a new formation, also, of red blood-corpuscles and blood-
vessels.

(c) Formation of Red Blood-corpuscles and Blood-vessels.

244

CONNECTIVE TISSUE.

Having ascertained the fact that red blood-corpuscles originate
in places where a transformation of cartilage into bone takes
place, I studied the development of blood-vessels in the same

Fig. 98. — Femur of a Newly Born Pup. Tr^v^tsition of the Epipm'sis

rSTTO THE DlAPHYSIS. No CaLCIFICATIOX OF THE BaSIS-SUBSTANCE.

Sagittal Sectiox. Chromic Acid Specimen.

C, lieaps of cartilage corpuscles ; H, newly formed nieiliillary corpuscles in a territory ;
^[, both cartilage coipuscle.s and basis-substance changed into medullary tissue, with traces
of Hewl3- formed blood-vessels. Magnifii-d 500 diameters.

situation. My subjects for investigation were condyles of the
femur of pups and rabbits and the cartilaginous border of the
plate of the scapula of kittens.*

* Translated from " Ueber die Riick- und Xeubildung vou Blutgefassen
ira Knochen uud Kuorpel." Wiener Mediz. .Jalirb., 1873.

CONNECTIVE TISSUE.

245

The hyaline ('pi})liys('al ciirtilaj^^t' of youusj: animals, as is well
known, is traversed by elonj^ated medullary spaces, which contain,
besides blood-vessels, ineludinji: arteries, a larjj^e number of ele-
ments similar to those Iillini>- the medullary spaces of the bone.
Such spaces also per\'ade the hyaline cartilajje at the border of
the plate of the scapula.

Fig. 99. — From the Calcified Nucleus of the Condyle of Femur of
A Dog, Six Weeks Old. Fresh Specimen. [Published in 1873.]

C, coarsely granular cartilage corpuscles with offshoots ; JT, haematoblasts, iu a club-like
space, which is inclosed by delicate spindles anil terminates in a solid point, P ; L, calcified
baiiis-substauce. Magnified 800 diameters.

In the epiphyseal cartilage of the knee-joint of a newly born
rabbit's femur, I found a radiating frame-work of calcified basis-
substance, which, bordering a larger central medullar}' .space,
inclosed in its trabecidae a number of cartilage corpuscles and

246

CONNECTIVE TISSUE.

their iion-ealcifiod hasis-substanee. In the corresponding epi-
pliyseal cartilage of a pup of five days there was no dcpcjsition of
lime-salts present ; while the same cartilage of a pup six weeks
old contained a central semi-lunar calcareous nucleus, with its
concavity dii'ected toward the diaphysis, the trabeeulae of which
inclosed a number of medullary spaces'. The significance of this

calcareous deposition was
dr." J] already known to Heinr.

Miiller.

Within the calcified
portions of the cartilage
metamorphoses occur in
the medullary spaces,
which, with a simulta-
neous solution of the
calcareous frame, lead
to the transformation of
the cartilage corpuscles
into blood-corpuscles and
blood-vessels, as well as
into medullary elements.
(See Fig. 99.)

The process is the same
in advancing development
of bone-tissue at the bor-
ders of the diaphyseal or
intermediate cartilage, at
the border between the
epiph3'sis and the articular
cartilage, and at the bor-
der between the cartilagi-
nous and the bony plate of
the scapida. The central
yellow and shining portion
of the cartilage corpuscle
is transformed into a vesi-
cle, usually clul)-sliaped,
containing red blood-cor-
puscles. The swelled blunt
extremity of the club is dii-ected toward the periphery, while
the more solid pointed end lies toward the larger central medul-

FiG. 100. — From the Cartilaginous Bor-
der OF THE Scapula of a Kitten.
Fresh Specimen. [Published in 1873.]

C, yellow, bright, vaciioled cartilage corpuscles ;
IS, closed cartilage cavity, pontaiiiing red blood-cor-
imscles ; M, cltib-sUaped spaces, holding red blood-
corpuscles and haematoblasts. Magnified 800 dianis.

vnxxFJTivi': tjssi'k. 247

larv s])ao('S. I also occasionally met with club-sliapcd foi'inations,
holding a li«i:ht, finely ^raiiulai-, or an apparently strncturclcss
mass. (See Fi^'. 100.)

If several of these club-like formations, whether empty or
holdinj; red blood-corpuscles, were crowded toi^ether, they
assumed the appearance of a cauliflower-like rosette, the same
as after perfoi-ation of the calcareous wall between two neigh-
boriiifi- cartilaj^-e cavities, when the spindle- or club-shaped forma-
tions come next to each other. The solid i)oints or the walls of
older fornniti(ms of this kind l)ecame, after a time, hollowed out,
and thus a varicose reticulum of blood-vessels arose which, from
the very earliest jieriod of their formation, contained red l^lood-
corpuscles. Still later, the newly formed vessels may connect
with older blood-vessels, and their contents be taken into the
circulation.

(d) Fornitifioii of Hone from MedxUa* In newly born pups,
the formation of bone-tissue takes place within the medullary
tissue from the medullary elements. The bone-tissue appears in
the form of trabecule^, which occupy the middle, between two
Idood-vessels or groups of vessels (see Fig. 86). The basis-sub-
stance of the trabecul* is finely striated, and here and there is
also indistinctly lameUated.

The transition of medullary into bone-tissue is demonstrated
by the following forms :

In larger medullary spaces, between two blood-vessels, in the
longitudinal section of the bone, we often meet with groups and
tracts of spindle-shaped medullary elements. These are either
homogeneous, bright, of a yellowish color, or granidar, and sup-
plied with vesicidar nuclei, or they may be mtliout nuclei. They
are all separated from their neighbors by narrow rims. In
transverse sections these tracts appear as roundish or oblong
fields, composed partly of shining and partly of pale granular
lumps, which are the cross sections of the spindles. We also
encounter similar groups at the borders of already developed
bony trabecular, and their general shape always corresponds to
an elongated spindle or a rhomb.

From these groups the trabeculre arise, by means of a deposi-
tion of lime-salts at regular intervals in one portion of the

* Translated fiom " Untersuchungen iiber das Protoplasma. IV. Die
Entwickcluug der Beinhaut, des Knochens," etc. Sitzungsber. d. Wiener
Akad. d. Wissensch., 1S73.

248

CONNECTIVE TISSUE.

medullary cori)uscles, while another portion remains unchanged
and represents the bone-cor-puscles. In accordance with the
spindle shape of all medullary elements constitutin<ji- a tract, the
basis-substance assumes a striated appearance.

In growing animals, we often see rows of medullary corpuscles
at the borders of bone-tissue t(jward the medullary space, which
have been termed the " osteoblasts " by Gegenbaur. * That the
elements of these rows really produce the bone was acknowledged

^y^^yyA/^\.^

Fig. 101.— Cortical Substanck op the Tibia of a Dog, Six Months
Old. Transverse Section. Chromic Acid Specimen.

3f, meaullaiy space filled with medullary elcnieuts, which at tlie border of the bouctis.siie
have assumed the shape of " osteoblasts." Tlie ecuter of tlie medullary space is occupied by
a blood-vessel. *', first trace of the formation of a Ilaversiau system, composed of lenticular
territories, which give to the circumference of the system a fiuted appearance. T, f;l"l)ular
territories, evidently the starting formations of new systems of lamella". M.agnificd 500
diameters.

also by later observers, as Waldeyert and A. Rollett. J A row of
osteoblasts is evidently the basis of a future lamella of bone.

Before the infiltration with lime-salts takes place, a number
of the osteoblasts are transformed into finely granular bodies,

* Jenaisehe Zeitschr. f. Mediz. ii. Natui'wissenseh. 18G4 and 18G6.
fUeber den Ossificationsprocess." Areliiv f. Mikroskopisehe Anatomic.
Bd. i. 1865.

t " Handb. d. Lehre von den Geweben." Heransg. v. S. Strieker.

rOXXKC'IlVE TISSUE.

249

destitute of inielei. the eoiuieetion of wliieh with oacli otlier and
with iieiiih boring- forniatioiis of the huiiie nature is estalilished
l)y the delicate spokes whieh traverse the intervening light rims.
After the infiltration with lime-salts is a('eom])lished, an oi)tieal
dirt'erentiation of the lamella into single '' osteol lasts'' is pos-
sible in exceptional instances, when the lamella has the appear-
ance of being composed of polygonal fields. More freciuently
the optical boundaries of the single osteol)lasts fade, and only
central i)ortions of the lamella remain intact in the form of
bone-corpuscles. In this case, therefore, a number of proto-
plasmic l)odies have coalesced into a slightly curved lenticular
formation, a tissue-unit, the center of whieh is the bone-cell.

Fig. 102. — Vertebra of a Human Embryo, Five Months Old.
Horizontal Section. Chromic Acid Specimen.

^f, mcaullaiy space, with central blood-vessels and ineaullarj' tissue ; S, first-formed
globular territories, containing one or two central bonecorpusclfs, witli radiating offslioots.
The territories lie against tlie trabecula of the original culeitied basis-substauce of the
cartilage, F. Magnified 500 diameters.

A number of such lenticular territories constitutes a single
lamella of bone-tissue.

In the compact and the so-called intermediate substance of

250 CONNECTIVE TISSUE.

shaft-hones of growing' and adult animals, we encounter numer-
ous circular fields, containing- one or more hone-corpuscles. We
also find within the medullary spaces glohular hodies, containing
several nuclei, or only a number of nucleoli, sometimes exhibit-
ing a uniform coarse granulation, due to the large points of
intersection of the living matter. These masses, termed "myelo-
plaxes " by their discoverer, Ch. Robin, are likewise the predeces-
sors of bone formation, as I demonstrated in 1872.* Here a
portion of the protoplasma is transformed into basis-substance,
which at once becomes calcified, while the central portion is not
changed into basis-substance, and remains as the bone-corpuscle
or the bone-cell. (See Fig. 101.)

We often find lenticular, multinuclear masses in the shaft-
bones of growing animals, not only in the epiphysis at the
borders of medullary spaces, but also in the vascular canals of
the diaphysis. Such masses are separated from their neighbors
by light rims, but also connected with them by delicate spokes
of living matter. These are the first traces of a third kind of
tissue-units of the bone, the hotie-glohules, which are known by
Virchow to be the cell-territories proper. Each of these origi-
nates from a multinuclear mass, and each coutains one or more
bone -corpuscles.

Formations of this globular variety are met with also in the
calcareous nucleus of the epiphyseal cartilage, at the ossifying
border of the diaphyseal or intermediate cartilage, '' and in the
centers of calcification of short bones.'' [The last words are
newly added.] (See Fig. 102.)

The multinuclear bodies, which have sprung from medullary
elements, are, therefore, the regular bone-formers, appearing
first around the trabeculse of the calcified basis-substance of
cartilage, and later independently of other formations. It
depends entirely on the original shape of the medullary lumps,
whether the hone-tissue assumes a striated, laniellated, or globular
structure.

Bone, therefore, as well as all other varieties of connective
tissue, is a product of the medullary or embryonal tissue, the
elements of which either split into delicate spindles, resulting in
the formation of a striated basis-substance, or coalesce into len-
ticular masses, a number of which unite in the construction of
a lamella, or else coalesce into globular masses, from which arise
the globular territorial formations of the bone-tissue.

* "Studien amKnochen ti. Knorpel." Mediz. Jahrb., 1872.

COXXFJ'TIVI': TlSSl'K. 1>.')1

TiiF. Process of Ossification in Biuds. Hv \,. SciiilNKY.'

My ol)S«.'rviitions wi-rc iiiailo on ;i number of chickens uml pigeons of
♦liiVerent iiges, tlie cartilages of the knee-joint, preserved and ih-calciiieil in
chromic acid, being my subjects of study. Sagittal sections through the knee-
joint of birds demonstrate that tlie bulk of the hyaline cartilage decreases
with age, and that a transformation of cartilage directly into medullary ele-
ments and indirectly into bone takes place only in young animals. In older
ones completi'il bone-tissue bounds the cartilage, and in old pigeons the
medullary spaces of the bone produce elongations wliich at a certain height
penetrate the cartilage.

In sagittal sections of young animals, we see with low powers of the
microscope the following: At tiie articular surface, and near the perichon-
di'iiim, elongated, spindle-shaped cartilage corpuscles are found, which gradu-
ally change into globular, nucleated corpuscles. The latter are met with
in the middle portion of the cartilage, wliich is pervaded by medullary spaces,
containing blood-vessels. The layer of the globular, nucleated corpuscles is
followed by a narrow layer, in which there are small, fiat cartilage corpuscles
of a yellow-red color, bounding the district of calcification. The calcified
basis-substance produces a pretty frame-work, which blends with the first-
formed trabeculte of bone-tissue, surrounding the medullary spaces of the
epiphysis.

With higher powers, we ascertain that the calcareous fi'ame penetrates the
basis-substance of the unchanged cartilage by means of pointed ends. Within
the frame the cartilage cori)uscles are distinctly recognizable. In many places
the trabeculie of bone are directly attached to the calcareous frame, the
feature distingiushing these formations being the bone-corpuscles of the tra-
becula?. The medullary spaces are filled with globular, oblong, or spindle-
shaped medullary elements ; besides these we often encounter protoplasmic
masses of varying size, either multinuelear or destitute of nuclei, but uni-
formly gTanulated. Spindle-shaped elements are most prevalent in the center
of the medullary space, where the spindles are in connection with blood-
vessels. (See Fig. 103.)

The formation of medullary spaces is best studied in. horizontal sections.
First we recognize that at certain intervals a dissolution of the calcified basis-
substance of cartilage takes place. It is true that the dii'ect transformation
of the cartilage into free protoplasma, with the formation of bright lumps,
filling the medullary spaces, cannot be directly observed, but we may readily
deduce such a transformation, as all medullary spaces in the neighboi-hood
are inclosed by a calcified cartilage tissue, and the calcareous frame pi'ojects
into the medullary space, as if broken.

The transition of cartilage into medullary elements is initiated by the
deprivation of a cartilage tissue unit or teiTitory of its lime-salts. Adjoining
the zone of decalcified cartilage there is found a layer of protoplasma con-
sisting of numerous glistening lumps. These lumps are surrounded by a
light narrow rim, which is seen occasionally to be traversed by filaments.
The hunps bear a close resemblance to like formations in mammals,
which have been described under the name of "haematoblasts." The char-

* Extracted from the essay of Dr. L. Sclii)ue3-, in New York. " Ueber rten Ossifications-
process bei Viigeln." Arcliiv f. Mikroskop. Anatomic," Bit. xii., 1875. For the second part
of tliis i)ub)ication, see pajje 103.

252

CONNECTIVE TISSUE.

aeter of many places, one of whieh I have illustrated, forces us to the conclu-
sion that not only the cartilage eorinisclos, but the whole mass of living
matter stored up in the basis-substance of the cartilage, participates in the
formation of medulla. No other interpretation is adniissil)le, for a sudden
transition of an apparently struetin-eless basis-substance into a pi'otoplasmio

Fig. 103.

-Articular Cartilage of a Young Chicken.
Section. Chromic Acid Specimen.

Sagittal

C, liyalino cartilage; CB, calcified l)asis-siibstance of hy.iline cartilage; M, iueilullar3'
si>ace ; U, tralieculae of Dewl5' formed boue. Magnified 450 diameters.

mass takes place without a trace of an intei'veuing di%-isiou of the cartilage
corpuscles. (See Fig. 104.)

At the border where the cartilaginous basis-substance is dissolved, we not
infrequently meet with cartilage coi-puscles, partly imbedded in the basis-
substance, partly freely projecting into the previously formed medullary
space, but I never saw marks of division of such corpuscles. Instead of

COXXECTTVE TISSTE

253

assiiminff, as is {jcnoriiUy doiit', tliat a division of cartilagp oorpusclos takes
placo, it would ho lu'ttcr to liold that, in the |>rotoj)lasina set freo by licijH'fac-
tion of tlu> hasis-substancc, there is at certain intervals a new formation of
liviii';; matter, which results in the formation of the compact, ^listeninf^ lumps.
The multimudear jn-otoplasmic bodies, the " myelopaxes," accordinj^ to this
view, are simply freed territories of the eartilaije tissue, and we can easily
iinderstaiul tiiat occasionally a number of such teiTitories coalesce into a
common layer, before a further differentiation occurs.

Unquestionably, the cartilage tissue is directly transformed into medullary
tissue. The question how bone-tissue arises from medullary tissue is answered
by the careful study of ]»laees where newly formed bone is closely attached to
calcified cartilage. Here we notice a regular layer of finely granular osteoblasts

Fig. 104. — Kxee-joint Cartilage of a Young Chicken, Close to the
Border of Ossification. Horizontal Section. Chromic Acid Speci-
men.

C, calcififU frame of basis-substance of hyaline cartilage ; 11, zone from which the lime-salts
liave been dissolved ; M, uewly formed medullary space. Magnified 700 diameters.

between the decalcified basis-substance of cartilage and the newly formed
bone. We can also trace every transition of free, uninfiltrated osteoblasts
from the fii-st steps till they finally fade in the basis-substance. The delicate
gi-anulation of the new osteogeneous basis-substance indicates that in the
formation of bone the structure of the osteoblasts has not been completely
lost.

The bone of birds is essentially constructed like that of Tuammals. We
find sy.stems of lamella? around vasctilar canals ; we also find in the cavities
of the basis-substance the bone-corpuscles, with their characteristic stellate
offshoots. How far the presence of living matter within the basis-substance
of the bones of birds corresponds with that of the mammal, further researches
must reveal.

254 CONNECTIVE TISSUE.

Development of Bone from Fibrous Connective Tissue.

A great part of the skeleton grows from fibrous connective
tissue, independently of preformed cartilage. The strict distinc-
tion which in former times was made between " cartilaginous "
and "covering" bones (see page 237) can be upheld only to a
certain extent. It is true that in the production of covering
bones no preformed cartilage participates, yet all the other
bones of the skeleton, including the flat, the short, and the shaft
bones, obtain only a part — viz., their cancellous portion, from
preformed cartilage. Their cortical or compact portion is formed
entirely from periosteum. Many observers have noticed, in dif-
ferent places beneath the periosteum, cartilaginous layers ; but
no importance need be attached to the presence of such a layer,
as the formation of bone-tissue is materially similar, whether it
is developed from cartilage or from fibrous connective tissue.

In the shaft-bones of human embryos ten to twelve weeks old,
when no trace of calcification is yet noticeable, the cartilage is
found to be surrounded by a delicate fibrous investment, — the
periehondi'ium, — between which and the surface of the cartilage
there is a broad layer of medullary tissue. From the latter
tissue arises the future cortex, simultaneously with the calcifica-
tion and ossification of the cartilage in the center. At the foiir-
teenth week there is ah-eady a distinct cortex around the
diaphysis, at the same time when the transformation of the
cartilage into medulla and cancellous bone has also commenced
in the central portion of the diaphysis. The cortex and the
calcified cartilage occupy about the same height, the middle por-
tion always being the starting-point for their formation. Both
portions, however, at first exhibit the cancellous structure, while
the formation of regular lamelln? liegins to appear much later.

The first-formed cancellous bone of the cortex has a striated
structure agreeing with the spindle-shaped territories of the
mother-tissue — the periosteum. The first-formed cancellous
bone of the center, on the contrary, is composed of globular ter-
ritories corresponding to the globidar territories of the mother-
tissue — the cartilage. It is only on this ground that we are able
to understand the difference in the structure of the earliest-
formed bones, the formation of '^ perforating fibers,'' and the
vascular system of the cortex. The law, however, according to
which the peripheral lamellae and the Haversian lameUas are
formed is not known. Probably there are three main layers in

CONNECTIVE TISSUE.

the oriijiiial periosteum, tlie filxM-s and ])1()()(1-V('ssels of
stand at ri«>:lit anjifles to eacli other.

Tlie formation of hone frinn fihnms eouneetive tissue
studied in tlie skull of the human emhryo, at about the
month of develoj^ment. (See Fig-. lUo.)

L'.).)
whirli

is best

fourth

, Y) .ill 'FA vr

f V.

111

Fig. lO.j. — Skull of a Human Embryo, Four Months Old.
Horizontal Section. Chromic Acid Specimen.

-V, uuiscIc-laj'tT of tlie scalp; .5.V, .sulmiuscular loose, freely vascularized connective tis-
sue: /', ilense connective, tissue of external pericranium; 5, tirst-forined trabecula; of bone;
O, layer of osteoblasts, attached to the trabecuUe ; Tiil, dense connective tissue of internal
pericranium — the future dura mater. Magnified 100 diameters.

256

COXXECTIVE TISSUE.

We observe in the middle of a layer of fibrous connective
tissue medullary corpuscles in longitudinal tracts (if cut trans-
versely) ; we see that a number of such corpuscles coalesce in
order to be transformed into basis-substance, which almost
instantaneously becomes infiltrated with lime-salts. In this way

■^'U

. I'

.V'

*,;

l-X' ■

W ■■''.

H

Fig. 106.— Skull of Human Embryo, Four Months Old.
Horizontal Section. Chromic Acid Specimen.

I", fibrous connective tissue of the pericranium ; -V, medullary space, witli ccnti-al
blood-vessel ; S. first-fonncd trabecula of bone : O, row of osteoblasts ; C, medullary cor-
jtuscles of the inner peiicianiuni, infiltrated with liuie-salts. Magnified 500 diameters.

trabecula? of l)one, with large and irregular bone-corpuscles, are
formed between two layers of fibrous connective tissue, the
outer of which is the future external, the inner the future inter-

coxsi'jTivi-: Tissrh'. 257

nal. pcricraniuin. Five or six years after ])irtli, the latter sej)arates
from the skull-lxtiie and furnishes the dense investment of the
brain, the dma mater. The lii-st trace of a bony formation is
invariably found in the mi(hih' fiehl between two IJood- vessels,
in those hx-abties, therefore, where there is tlie least nutrition, in
the same numner in whi(^h the })ony fornuition arises from carti-
lage. The further g;rowth of the trabeciiltv always pro(;eeds from
the medullary tissue, partieularly fi-om the medullary eorj)Us<'les,
usually of only one side, lyini;- close to the border of the tra-
l)eeida. This process is identical with that of the gi'owth of
trabecida' which have arisen from original cartilage.

For studying the details of the formation of bone from fibnms
connective tissue, with higli amplifications of the microscojje, the
best subject also is the skull of a human embryo. (See Fig.
106.)

We observe at fii'st that, from single medullary corpuscles,
often grouped together, basis-substance originates, which is at
once infiltrated with lime-salts. The embryonal condition is next
reestablished in these corpuscles by liquefaction of the basis-
substance, and they are again plastids, which may afterward
coalesce to form a larger mass, the fii'st indication of a territory,
exhibiting a central bone-corpuscle. Still later, a number of
such masses, always through the intervening condition of uncal-
cified medullary tissue, coalesce, and a trabecula arises, with a
number of large and irregular bone-corpuscles, with their stellate
offshoots. It makes no difference whether a blood-vessel is pres-
ent from the beginning of the process, or whether it is formed
afterward; it "svill always occupy the center of a medullary
space. Upon close observation of the distances between the
single bone-corpuscles, we are satisfied that at first from only a
single 'corpuscle, and later from a limited number of medullary
corpuscles, calcified basis- substance arises in the same manner,
therefore, in which the myxomatous basis-substance is formed
(see page 148). At first, no distinct territories are present; these
are only recognized later, when the lamellated structure begins
to appear.

Obviously, the originally formed bone-tissue is not perma-
nent. The bony trabecida* in tiu-n are repeatedly reduced by
liquefaction of their basis-substance to the eml)ryonal or medul-
lary condition, and new bone-tissue continues to form up to the
time of full development of the body. A continuous absorption
and reformation of lione is probably going on throughout life.
17

258 CONNECTIVE TISSUE.

This, to some extent, is influenced l)y certain coiiditioiis — for
example, on the skull-bones by the growth of the l^raiu, Ijoth in
a progressive and regressive way (Virchow). The regression is
shown by the absorption in advancing age, producing the thin-
ning of the bones so characteristic of the senile skeleton.

The Growth and Retrogression of Bone.

In the light of my researches, continued for ten years, the
theory of an interstitial growth of the bone is no more tenable
than is the interstitial growth of any other tissue. Basis-sub-
stance, once formed, cannot increase in bulk by simple expansion.
The observation that the bone-corpuscles in the old are farther
separated than in the young is no proof of an interstitial growth,
since Steudener has demonstrated (see page 220) that the periph-
eral portion of each bone-corpuscle in advancing age is trans-
formed into basis-substance. New tissue forms exclusively from
embryonal or medullary tissue, and <in already formed tissue must
return to its embryonal condition, by liquefaction of the basis-
substance, before a new tissue can arise. An augmentation of the
bulk of a tissue can talie place only by new formation of the
living matter of the embryonal corpuscles.^ that is, an increase of
the number of the embryonal corpuscles.

This law was first, though incompletely, establislied by H.
Midler, in 1858 ; it was asserted as to the growth of bone-tissue
by L. Ranvier in 1865, and announced to be a universal law for
all tissues by myself in 1873. The process of inflammation, first
accurately studied by S. Strieker, also illustrates the law. In-
flamed tissue, according to 8. Strieker, returns first to its embry-
onal condition before new formation arises.

We are indebted to A. Kolliker's accurate researches * for the
discovery that every growing bone on its surfaces exhibits regu-
larly recurring '' planes ot resoi^jtion " (Resorptions-flachen). The
bone to the naked eye looks rough, as if coiToded ; under the
microscope the bone-tissue proves to be spongj^, pro\'ided with
bay-like erosions or excavations, which, as a rule, contain multi-
nuclear bioplasson masses. KoUiker maintains that these bodies
are growing into the bone-tissue from without, and that they
actually absorb and destroy the bone structure. For this reason

* ' ' Die Normale Resorption des Knochengewebes u. ihre Bedeutung fiir
die Entstehimg der T\-pisehen Knoehenformen." Leipzig, 1 873.

CONNECTI I '!<: TISSUE,

259

he proposed for tlit-ir (Icsijjnatioii tlic rutlicr ;iliU'miiiL:,- iiiiiiK' of
l)Oiio-l)iTak('i's — "ostt'oklasts."

The iiiultimiclcar bioplasson hodios were first described by
Robin uiuU'r the title of " mycloplaxes." Virchow termed the
same forinations "giant-cells''; English anthors, "myeloid
cells." They are, as I demonstrated in 1878 (see chapter on
iiitlamination), the bi()])lassoii formations of the bone-tissue itself,
the teri-itories of the bMsis-substanee of )>one, (Mthei- after decalei-
fication and liquefaction of the basis-substance, or before the
formation of a territory of ])one. (See Fig. 107.)

Ij

.1)

Fig. 107. — Surface op the Scapula op a Kitten.
Chromic Acid Specimen.

C, lanielLitt'il bone, with bone-corimscles ; G, a siugle territory of boue-tissue liquefleil,
reBulting in the formation of a niultiuuclear plastid; M, coalesced masses of multlnuclear
Itlastids. Magnified GOO diameters.

We see these bodies, not oidy in medullary spaces of all
juvenile bones, but also in the planes of absorption at ihe surface
of growing bones, l)eneath the periosteum, and in inflamed l)one.
They certainly are not extraneous, but the medullary corpuscles
themselves, coalesced into larger layers for the production of

260

CONNECTIVE TISSUE.

territories in forming bone. An already formed bone, being
deprived of its basis-substance either by advancing- gi-owth or by
the inflammatory process, at once falls back into the bioplasson
stage, and exliibits fli'st bioplasson territories, which later again
divide into mednllarv^ corpuscles. All territories and all medul-

-. J

< <

lary plastids remain interconnected by means of delicate filaments,
which traverse the sm-rounding light rims, and such a connection
is also established with the adjacent reticulum of bioplasson of
unchanged bony basis-substance. In these masses we usually
obsem^e all stages of development of bioplasson, from the solid

COXXECTTVE TTS'sri':. 201

homoiivnoons luni]) into ii nucli'atcd })lasti(l, and from this into
plastids with nucU'oli only, and linally into ^ranuhir phistids,
destitute of nuclei and mieleoli. (See paji^e oo.)

The interpretation here <i,iven does uot, however, explain the
appearanee of sueh l)ioplasson bodies in dead bone. Ivory sticks,
driven into living bone for surgical or experimental purposes
(Billroth), and necrotic bone like^\'ise, exhilMt l>ay-like excava-
tions at their surfaces, tilled withmultinuclearl)ioplasson masses.
01)viously, these masses could not have originated from the dead
ivory and the necrotic bone. Their bay-like excavations are ex-
plicable, as Yii-chow has already shown at length, by assuming
in them a decalcitication and liciuefaction of the basis-substance.
coiTespondiug with the territories ; and, since Ziegler has demon-
strated that even between two thin glass plates, placed into the
subcutaneous tissue of animals, migrating plastids accumulate
and coalesce into nudtinuclear masses, a similar process may be
admitted for the filling of these bay-like excavations.

That the multinuclear bodies really arise fi-om the Hquefled
living bone-tissue itself I have ascertained in provisional teeth,
the erosions of which were studied, in the last few years, in my
laboratory, by Dr. Frank Abbott; and there can be no doubt
that they are a growth of meduUary corpuscles from without,
whenever the bone is deprived of its life.

Cartilage with advancing age gradually decreases in amount ;
in the aged we find only a thin layer of articular cartilage. In
old dogs, the thin layer of the articular cartilage, toward the
marrow spaces, is bordered by a well-marked lamellated zone
of bone. (See Fig. 108.)

That the bone-tissue itself does decrease in bulk with advanc-
ing age is best illustrated by the toothless jaws of the aged.
The cause of this absorption and atrophy of the bone-tissue,
invading both the cancellous and compact structure, has not yet
been elucidated.

VIII.

MUSCLE-TISSUE.

MUSCLE, the motor apparatus proper, is a formation of
living matter in a reticular arrangement. The points of
intersection in smooth muscle are irregularly scattered ; in
striated mus(.-le, they are aiTanged w-ith great regularity in the
so-called sarcous elements. The connecting filaments are ex-
tremely delicate, allowing slow but, considering the bulky forma^
tions of muscle, powerful contractions of the living matter.

Muscle is constructed on the plan of an amoeba, or that of
any other plastid. The difference is that the points of inter-'
section of the living matter in the amoelm are small and irregu-
larly distributed, while in muscle the nodules of the reticulum
are large and more or less regular in their arrangement. The
fluid contained in the meshes of the reticulum in the amoeba
corresponds to the muscle fluid between the rows of sarcous ele-
ments. Contractility is inherent in the amoeba and every plas-
tid; therefore, also in muscle, independently of nervous influence.
The independent contractility of miiscle was proved by J. Miiller.
in 1834, after division of the nerves, and by Claude Bernard, in
1857, after abolishing the action of the motor nerves by curara.
The enlargement of the nodules of living matter, the shortening
of the connecting filaments, and the narrowing of the mesh-
spaces produces the contraction in the amoeba, as well as in the
muscle (see page 29). The difference is that, while in the amoeba
one portion of the body is in contraction, the other, on the con-
trary, in extension : in all highly developed animals one muscle,
or a group of muscles, is in the state of contraction, while

MUSCLE-TISSrK. 263

anotlior iinisclc, or a ^roup of imiscles, is in that of extension.
Muscles which simultaneously work in such an ojtposite manner
are termed " antagonists."

Muscle formations are of two varieties. In the tissue of
the inisfriped, snuxitli, or iuvohintary muscle the bioplasson is
stored up, without much regularity, in comparatively small spin-
dles. In the tissue of the striped or rolimfdri/ niuscle the hioplas-
sou is distributed regularly in the shape of sarcous elements, in
relatively large spindles.

1. Smooth or Unstriped Muscle.

Smooth muscle is constructed of spindle-shaped plastids,
which are usually nucleated, and are held together in bundles
by means of a delicate cement-substance, surrounding each
spindle. Ensheathing the bundles there is a delicate layer of
fibrous connective tissue, the perimysium. The muscle nature
of these spindles was discovered by A. Kolliker in 1847.

The spindles vary greatly in size. Very small spindles are
found in the skin and large arteries, medium-sized spindles in
the muscle-layers of the mucous membranes, and very large
spindles in the pregnant uterus. In all instances the separating
cement-substance can be stained brown by nitrate of silver, and
the brown line thus produced is pierced at right angles by deli-
cate light lines which correspond to the minute transverse
spokes interconnecting all spindles. The spokes are visible with
high powers of the microscope, wdthout the addition of a re-agent.
The granules of the spindle are, as a rule, coarse, so as often to
conceal the central oblong or rod-like nucleus, which, however,
is easily seen in transverse sections. The granules not infre-
quently exhiljit a partially regular aiTangement, especially
toward their tapering ends, which produces an appearance
resembling the sarcous elements of striated muscles. The out-
lines of the spindle are smooth and regular when in a state of
rest ; but they become slightly scalloped by contraction, when
the body of the spindle is shortened and broadened.

The bundles of smooth muscles of the skin are most abundant
in the region of the nipple and in the scrotum. They run in
oblique directions, interlacing sometimes at acute angles. The
oblique section of a bundle is characterized by short spindles ;

264 MUSCLE-TISSUE.

the transverse section hy disks, exhihiting, when the razor has
passed thi'oiigh the middle of the spindle, tlie bright central
nucleus. (See Fig. 109.)

Bundles of smooth muscle are often found connecting into a
reticidum — f. i.. in the scrotum, the labia majora, the prostate
gland, the urinary bladder. The bundles are spread in flat
layers throughout all larger tubular formations of the ali-
mentary and the genito-urinars' tract. We find in these tubes
at least two layers, of which the one nearest the epithelial sur-

// '\ r-M.\'^^^ 0Mf>i\

;/

i

^i\v¥.

L-

Fi6. 109. — BtrxDLES of Smooth Muscle in the Derma of the Skix
OF the Nipple. Chromic Acid Specimen.

L, longitudinal, O, oblique, T, transverse section of a bundle ; D, derma of the skin ; -V,
probably termination of a nerve. Magnilied 500 diameters.

face is cii-cular, and the other longitudinal. In the intestinal
tract the mucous membrane has two delicate layers (transverse
and longitudinal), while the tube possesses in addition two
layers, of which the circular is far more developed than the
longitudinal. In the stomach, the bladder, and the uterus,
numerous oblique bundles run between the circular and
longitudinal. In the lower third of the oesophagus smooth

MUSCLE-TISSUE. 205

miiscU's appear, r('j)lacinj? the striped iiiusclrs, wlticli arc present
in the two n])])er thirds; tlie bonndary line between the two is
not shai-jjly marked, as the lilx'rs of botli varieties Ijh'nd with
each other (Treitz).

The j)re^nant uterus is constructed <»f numerous and hir^e
muscle-fibers, also arranged in longitudinal, transverse, and
obli(iui' buudles. Tlie biojdasson in this situation is very abun-
dant, ^iviny tlie spindles a coarsely granular, nearly homogene-
ous, appearance, without a distinct nucleus. Every large spindle
is eonij)<)sed of a number of smaller ones. The boundary line
between the latter is often marked at the periphery of the large
spindle only, or else a faint ol)lique trace of demarcation may be
observed within a large spindle. (See Fig. 110.)

Blood- and Ljirnph-cp^sels are numerous in the smooth muscle-
tissue, producing an elongated, more or less rectangular, reti<'-
ulum. Larger blood- and lymph- vessels are found in the denser
formations of connective tissue between groups of bundles,
whOe the delicate perimysium surrounding the bundles contains
only capillaries.

The nerves of smooth muscle bundles, after repeated plexi-
form ramifications, branch in the form of delicate axis fibrillae
in the cement-substance l^etween the spindles (M. Lowit). Some
observers claim that the axis fibrilltp enter the spindles and ter-
minate in the nucleolus (Frankenhauser), or pierce the nucleus
and the nucleolus, in order to again reach the plexus on the
()p]K)site side of the spindle. Here, as well as in striated muscle,
a terminal nerve-hill may exist, as indicated in Fig. 109, though
its relations are not yet sufficiently studied.

2. Striped Muscle.

Striped muscle is composed of comparatively large f usiforni
and sometimes blunt spindle-shaped fibers, whi(ih are separated
from each other by means of a delicate connective-tissue forma-
tion, and are held together in bundles by means of broader lay-
ers of the same tissue. Each bundle is composed of a varying
numljer of fibers. The fiber is built up by more or less regularly
arranged layers of sarcous elements, — formations of Inoplasson,
— which are interconnected in all directions by delicate filaments
of bioplasson, while the meshes between the sarcous elements
contain a non-contractile, non-living fluid, which can be artifi-
cially pressed out of every muscle.

266

M USCLE- TISS UE.

The distri))uti<)n of the muscle-fibers in the })elly of a muscle
is best observed in transverse sections, with lower powers of the
microscope. (See Fig. 111.)

Each fiber is surrounded, and a certain number of them are
inclosed, by fibrous connective tissue, the former being termed

Fig. 110.— Bundles op Smooth Muscle of the Human Uterus,
Shortly after Delivery. Chromic Acid Specimen.

L, loiifritinliniil, 0, oblique,, T. Iraiisvorsc section of buiidles : P, periraj'sium, coiitaiuinp
blood-vessels, ('; A', i)histi(ls in tlie connective tissue, ]ii()l)alily tbe first traced muscle-fibers.
Magnifietl 500 diaineters.

internal perimysmm^ the latter, external perimysmm. The con-
nective tissue is the exclusive carrier of blood- and lymph-ves-
sels, also of the nerves, and often contains fat-globules. The

^fr'S('LK-TrssrE.

267

oxtornal jx'rimysiuin unites into tendinous septa, and these
unite to form the faseia' and aponeuroses.

Each niusele-fiber, besides, is again inch)sed by an extremely
delieate liyaline, ehistie membran(\ — the sftrrohnniid, — tirst de-
scribed l)y Th. Schwann, in bs;{9. This sheath has not yet been
found in the muscle of the heart. The sarcoleinnia is distinctly

Fig. 113. — Rectus Muscle of the Eyeball of Max. Trans-
verse Sectiox. Chromic Acid Specimen.

PJC, external perimysium, containing, besides fat-globules and capillary blood-vessels,
also an artery, A. and bundles of medullated nerves, iV; PI, internal perimysium, enslieatli-
ing the single muscle-libers. F. Magnified 200 diameters.

seen only in transverse sections of muscle-fibers, but it becomes
visible also in loujj:itudinal fibers, when broken through, or
after treatment with dilute acids, which destroy the muscle-
tissue without attacking the sarcolemma. The sarcolemma
appears as an apparently structureless, extremely thin, cor-
rugated membrane, destitute of nuclei. (See Fig. 112.)

The attachment of the muscle-fiber to tendinous or periosteal
tissue is by means of the internal perimysiiun, while the sarco-
lemma terminates around the blunt or sharp point of the muscle-
fiber (C. Toldt). The tendons often exhibit rounded excavations,
in which rest the blunt ends of the muscle-fibers; thickened
elongations of the tendon penetrate to various depths between
the blunt extremities of the muscle-fibers. The perimysium,

268

MrsCLE-TISSUE.

after hleiiding; with the tendon or periosteum, is, as a rule, sup-
plied with a large number of plastids. (iroups of plastids are
sometimes seen filling the triangular space above the point of

Fig. 112. — Muscle of Tongue op Max. Chkomic Acid Specimen.

i, longitudinal muscle-liber, broken off and exliibitinir its .structureless sheath — the sar-
i-olemma, .S'; 2\\ medullated nerve-fiber, terniinatinfr in the motor liill, H ; T, transverse sec-
tion of a mnscle-flber ; P, the perimysium, hohluig capillar}- bl()o<l- vessels, (', and nerves, A"'.
Majrnified 500 diameters.

the musele-fiber, which often looks as if split into small spindles,
with sarcous elements iiTegularly distributed. (See Fig. 113.)

Regarding the minute structure of striped muscle-fibers, there
is the widest divergence in the views of histologists. Still, the

Ml'sci.E.TIssrK.

269

structun* is i-xti-cincly simple, iiiid proved to 1)<' so l<y the
(leserii)tion of E. liriicke, in IS.')? (see paji^e 127). The only addi-
tion I have to make is lliat all sareous ek'nients, whatever may
1)6 their size and arranu-ement, are uninterruptedly connected in
both longitudinal and transverse directions. The division of
the muscle-fiber into the hm^itudinal fibrilliTe of Schwann
depends n])on a very ch^se afjcj^regation of the sareous elements
in a lon<>;itudinal direction. The beaded ai)pearanc,e of these
tibrilla^ can be ex])lained only by the })resence of filaments, con-
neetiug the sareous elements
in a lenofthwise direction.
Muscles ke})t in alcohol ex-
hibit this characteristic very r-
distinctly. If, on the con-
trary, sar(H)us elements art
aggregated more closely in
transverse dii-ection, either
after mechanical injuries, by
teasing, or after the applica-
tion of certain re-agents,
such as dilute muriatic,
nitric, lactic acid, or the ^
stomachic juice, Bowman's
disks will be the result.

The smaller the sareous
elements in a muscle-fiber
are, the more rapid and con-
tinuous the action of the mus-
cle, and vice versa. The heart,
being the most active of all
muscles, has the smallest sar-
eous elements. The slower , -^'- i'"'"*''') *'"'' "\ '""«cie-fiber; s, the sarco-

leiuniu, closely attached to tlie perimysium, Fy
an animal in its motions, the which bleiuls wltli the llhrous connective tissue of

larger are its sareous ele- i'"''"^^''""'- Ma,..ifiea 500 diameters.
ments. In accordance with what I said on the structure of bio-
plasson in general, it will be readily understood that contracti-
bUity is increased with the smallness of the points of intersection
of the reticulum. Normal, fresh muscle-fibers sometimes exhibit
very small and irregularly distributed sareous elements and
active contractions under the microscope. Muscles of the craw-
fish, the lobster, and the water-beetle are, on account of the large
size of their sareous elements, excellent objects for study. As

M-

Fig. llo. — Attachment of Muscle-
fibers TO Periosteum. From the
.Scapula of a Cat. Chromic Acid
Specimen.

270

MUSCLE-TISSUE.

SI

Briieke has stated, the arraiig:ement of the sarcous elements in
the live iniiscle-filier g-reatly varies ; the reasons for this are not
yet clearly understood. Nevertheless, the schema of the struct-
ure of muscle-fiber was established by Hen sen under conditions
when the rows of sarcous elements were divided by a single
transverse light line, and Merkel divided this line into two. A.
Schafer adopted the schema of two narrow rows between two
broad ones. All these conditions are sometimes met with, but
they are not by any means the only, or the most common, ones.
The theories of Krause's muscle-caskets, and Schafer's connect-
ing lines, between the two narrow distal rows, have arisen from
the erroneous idea that the filaments run hetween the sarcous
elements, while in reality they directly connect them, often at

their edges. Not infrequently
_^l the sarcous elements, under the
microscope, appear in oblique
position, owing to the general
spindle shape of the muscle-
fiber, and a dark line is seen on
one end of the sarcous element,
which is a shortened view of its
lu-eadth. This dark line, also,
had led observers to wrong con-
clusions.

Chloride of gOld is a good
re-agent for bringing to view
with great distinctness all the
above-described features. That
the narrow rows themselves are
composed of small, sarcous ele-
ments is shown in Fig. 114.
This condition is exceptional,
and still more so is the appear-
ance of double narrow rows,
compared with the appearance
illustrated in Fig. 41, page 128.
That in one muscle-fiber different arrangements of the sarcous
elements may occur, can be seen in the muscle of craw-fish.
Often in the fresh muscle the regular rows disappear, and a
uniform granulation is for a moment \dsible, while in the next
moment the rows are reestablished. In all these conditions the
muscle-fiber executes contractions. (See Fig. 115.)

Fig. 114. — Striped Muscle of the
Water-beetle (Hydrophilus Pi-
CEUs). Stained with Chloride of
Gold.

<S'', row of large, and S"^ row of small, sar-
cous elements, the latter stained deeper violet
than the former. All rows intereimnected by
delicate filanu-nts. P.etwccn tlic rows an un-
colored liquid. Maf^nificd 1200 diameters.

Ml'SCLh'-TfS.STi:.

271

Till' coiitractioii of ji lunsclt' to tlic naked (",•<• consists in the
shortt'ninfj^ and the liroadeniny; of its belly. Accoi-din^dy, w*; sec
under the luieroseope, in a contracted mu.scle-filxi-. all the rows
of sarcons elements ajiproaehinii: each other, and every sareous
ek'nient l»eeonuni<: hi-oader. This is done at the ex])ense of the
connecting filaments, which become shortened. The liipiid be-
tween the rows spreads by
pressure in tht; transverse
direction. By contraction,
nothinii,- is lost from and
nothin«i- added to the mus-
ele-tiber. In extension the
nmscle-fiber is elongated,
and accordingly the sar-
eous elements gain in
length and their rows sepa-
rate. Ranvier drew atten-
tion to the presence of two
kinds of muscles even in .s.
mammals, especially in
rabbits — the pale trans-
parent and the red opaque
varieties. He claims that
the pale muscles contract
more rapidly, upon appli-
cation of the galvanic cur-
rent, than the red ones ;
that the pale muscles have
a more marked transverse
and the red a more- marked longitudinal striation, and also that
the nuclei of the pale mus(;les are less numerous than those of
the red.

In transverse sections of muscle-fibers (see Fig. 112) we often
notice a central, pale, irregularly granular nucleus, or sometimes
two such nuclei. Instead of, or in addition to, granidar nuclei, we
also see small, irregular, solid lumps of T)ioplasson in the midst
of sareous elements, which formations correspond to the oblong
nuclei and to the rows of coarse gi-anules in a longitudinal sec-
tion. From the central nucleus radiating offshoots emanate,
which interconnect the coarse granules, and group the sareous
elements in circular or radiating formations, which are sometimes
very gracefully arranged. These are the celebrated muscle-nuclei

Fig. 1 1 o. — Striped Muscle of the Craw-
fish (ASTACUS FLUVIATILIS). StAIXED

WITH Chloride of Gold.

.S'>, row of large sarcou.s elements, splitting into
rows of smaller ones, -S'2 ; lietween tlie rows of liirsre
sareous elements rows of small ones ; all rows inter-
connected ; y, nuclei on the sui-face of the fiber.
Magnified 1200 diameters.

272

MUSCLE-TISSUE.

§ik

.:v'\':':V

of Max Scliultze. They are evideutly reinuaut.s of the embryoual
development, *' undifferentiated protoplasm," as M. Schultze
himself said. They often fall ont, especially from very thin
sections, and leave one more central or two more peripheral
openings, bounded by a jagged or stellate outline.

The formations termed nuclei really reveal the history of
development of the muscle-fiber. Each fiber is constructed on the
plan of a bundle of connective tissue — for example^ the tendon. It
is likewise composed of one large or a number of smaller territories,
and each territory has resulted from the coalescence of a number
of plastids^ some or portions of which remain unchanged solid or
granular bioplasson, while in all surrounding plastids the points

of intersection of the bioplasson re-
ticulum assume the regular ar-
rangement of sarcous elements.
At the borders of the territories
sometimes a layer of elastic sub-
^-^ stance is formed, and a whole
system of territories is, as a rule,
ensheathed by a solidified, so-
called elastic substance, the sar-
V eolemma, an offspring of the bio-
plasson liquid. Th. Margo was
the first observer who proved
})ositively that each muscle-fiber
arises from a number of plas-
tids. the so-called '' sarcoplasts,"
against the \TLew inaugurated by
Schwann, that a single muscle-
fiber is an enormously grown
" ceU;'

In some places the muscle-
fibers have been found bifurcat-
ing, f. i., in the tongue, the
muscles of the eyeball, and the heart. In the heart the muscle-
fibers are very small, freely branching, and united into bundles
in the manner of a felt- work. It was said before that here the
sarcous elements are extremely small, while the nuclei are very
numerous. This is the only muscle which for eighty or more
years is in continuous activity — the first to begin and the last to
stop. (See Fig. 116.)

The medullated motor nerves, upon entering the muscle, split
into nimierous branches, which course in a transverse or oblique

cp-

\

'J

^•1

Fi

116. — Muscle of the Heart
OP A Newly borx Child. Lox-
GiTUDiNAL Section. Chromic
Acid Specimen.

^'-V,uuclei on the surface of the niuscle-
tlber ; CP, delicate perimj-sium, with oblong
nuclei and capillary blood-vessels. Magni-
fied 500 diameters.

Mrs(i.i-:-rissrj':.

2T)

diivction alonu: tlic filuTs ; tlic branches, repeatedly l)ifui-eatiii}r
and eonneetin*!;, prodnee a plexns in the periniysiuni. From tlds
])le.\ns ai-ise the terminal nerve-fihers, each of the nmseh'-fibers
Ix'inu" supplied with at least one fiber. In some amphi))ia, the
medidlatecl nerve-fiber penetrates the sareolemma and divides
into a number of h)n«!:itudinal axis fibrilLe on the surface of the
muscle. In most aninuils
there has l)een observed a
terminal disk, the " niot<n-
hill" of Doyere. This is
a finely jj;ranular discoid,
slightly elevated formation,
curving with the surface of
the muscle-fiber, with a num-
ber of faintly outlined nuclei .
The nuHluUated nerve-fiber
on reaching the hill becomes
deprived of its myeline in-
vestment, while the elastic
myeline sheath (Schwann's
sheath) fuses mtli the sareo-
lemma, so that the motor
hill, according to the views
of most observers, lies un-
derneath the sareolemma.
"W. Krause maintains its
position outside the sareo-
lemma (see Fig. 111). Kiihne
has found a broad layer of
fused medullated nerves
upon the hill in all higher
animals. The axis cylinder
of the nerve-fiber connects
directly with the delicate
bioplasson reticulum within
the motor hill, and this is
again connected by delicate
filaments to the next sarcous elements. Thus a coutinuoiis con-
nection between the nerve and the muscle is established by bridges
of li\'iug matter. Some medullated and perhaps sensorial nerve-
fibers branch in the perimysium without entering the formation
of the motor hills.
18

Fig. 117. — Striped Muscle of Cat.
Injected.

vl, artery: T', vein. Masnilied 800 ili.iiiieters.

274 MUSCLE-TISSUE.

Blood-vessels are very numerous in striped muscles. They
are seen running- in the external perimysium as larger arteries
and veins, and when reaching the surface of the bundle they
ramify into capillaries, which are fcmnd in the interniU perimy-
sium without entering the muscle-fiber itself. All vascular for-
mations of the striped muscle are characterized by very marked
bifurcations at riglit angles, and this is especially a prominent
feature of the branches of the arterioles and the first capillaries
arising from them. (See Fig. 117.)

Li/inpJi-resseh are also numerous formations in the tissue of
the striped muscle, and, as regular injections show, they always
form a closed system of capillaries, which accompany the arterial
and venous blood-vessels.

The Structure of the Muscle of the Lobster.
By M. L. Holbrook, M. D.*

When we read the liistory of those scientific investigations which have been
made by oiu" most excellent observers during the last forty years, we can
hardly fail to be convinced that even the simplest facts of natiu*al philosophy
are only established after long-continued and patient research. Truth is
rarely or never reached in a straight line, but only bj^ a tortuous and zigzag
course. At times we seem to have it almost within om- gi"asp, and then it
becomes lost to view, and we are compelled to seek for it in a new direction.
All this is true when applied to the research of muscular structure, as we
shall see.

The muscular system, as we know, constitutes the motor apparatus of all
complex animal bodies. Bj' it all movement from place to place, all change
of shape and form, are accomplished. All motions of the body are based upon
the contraction of the two varieties of muscle-fibers, for they possess in the
highest degi-ee the same property seen in every portion of living matter, in
every simple organism, in every plastid — the power to contract. From this
it is fair to conclude that muscle must also be living matter.

Our modern views on the structure of striated muscle date back as far as
the year 1 839, when Th. Schwann,! in his celebrated researches on the iden-
tity of the structure of the animal and plant, maintained that the striated
muscle is composed of innumerable, extremely delicate fibrillae, of a beaded
or rosary-like appearance. A number of such fibrillae, the beads of which
stand in one line close together, would, according to his view, form a
muscle bundle. If we look at a muscle-fiber, we notice alternating light and
dark lines of a definite width, and these, according to Schwann's view,
originated in the regularity in which the thick and thin portions of the
fibrillse are placed side by side.

W. Bowman { demonstrated that the fibers sometimes break up, when sub-

* Printed from the author's manusci-ipt.

t " Uutersucliuiijren iiherdie l'e))ereiiistinimiing," etc. Berlin, 1839.

t T()(l(Vs Cyilopediii, 1H4,«.

MrscLE-TfSsrE. 275

joctod tonicclmnical injuries or flicinii-iil n'-at^cnlH, intotrimsvcTSO disks. Tlic
(•U'iivaf;;o of tin» (ilxT lengthwise jjives us tlie filirillie, wliile a fransverst^
eleavatje jjives the disks. Hv spiittiu}.; tiie fibers in a loiif^itudinal and trans-
verse direetion, this investif^ator ol)taineil inuuineralde sniail cylindrical or
sijuare ])ieces. whiidi he called the sarcoKs elements. lie niaintaine<l with j^'c^at
l>ositiveness that tiie striations in the musclo-fiber are due to a diffenMice in
the refractinfx power of the intermediate sul)stanco, and that the lorif^ituilinal
and transverse splittinjij are not essential properties of the muscle, hut ai-e due
tomeehanieal or chemical injuries.

The next investigator wlio has thrown light on this subject was E. Briicke.*
This observer maintains that the sarcous elements are by no means invariable
and unchangeable formations in the living muscle, but that they are rows of
corpuscles, differently arranged at the moment of death. On examining the
fiber with polarized light, he came to the conclusion that tlie sarcous elements
are constructed of very small, invisible particles, which he named (lis(Ualdftst><.
Upon the grouping of these minute bodies, he believed, depended the varying
formation of the sarcous elements. Briicke argues that the rows of sarcous
elements are double refracting, while the spaces between them are only
simple refi'acting. As to the nature and consistence of these intermediate
layers he olTers no opinion.

C. Heitzmann t i)ointed out an interconnection of the sarcous elements,
both longitudinally and transversely, by means of delicate filaments of living
matter, in the same iiuuiner as the gi'anules of bioplasson in the ammba are
connected. My own observations point strongly to the correctness of this
assertion.

The observations of the investigators now mentioned are the principal
sources of our knowledge of striped muscle. The later researches on this
subject made by Hen sen, W. Krause, W. Engelmann, Heppner, and Alb.
Schafer have added little to our knowledge, as these authors have ex-
plained the structure of striped muscle in a complicated manner, and far
differently from what we really see. Perhaps Colmheim's discovery of the
peculiar fields in transverse sections of frozen muscle deserve a remark, as
they appear to have been formed by the process of freezing, as we shall see
later on.

If we take from the lobster a minute piece of perfectly fresh muscular
tissue and transfer it, together with a drop of the blood of the animal, to a
glass slide, and cover it quickly with a thin cover-glass, we may see, with
moderate powers of the microscope, the fibers composing it, of a nearly
uniform breadth. These fibers are separated fi-om each other by exceedingly
narrow light spaces or rims, which in some places contain a granular mass.
A number of fibers are kept together by a delicate fibrous tissue, in which are
held the vessels and nerves. These latter features are seen best in a trans-
verse section of the muscle. Within the fiber may be noticed two kinds of
substance; one is opaque, of a dim luster: the other is light, uncolored, not
shining. In many places the two substances alternate with each other in
such a way as to form rows, running in the transverse direction of the fiber, or
we may sometimes observe that the opaque substance is distributed without

•< " Untersucliinigen iiber di-n B.iu d. Muskelfasem mil Hulfe cles polar. Lichtes." Denk-
schr. d. Wiener Akati. Btl. xv., 1857.

t " x;uter.suclniiif,'eii iiljer das Protoplasiua." Sitzungsber. d. Wiener Akad. d. Wissensch.,
1873.

276

Ml'SCLE-TlSSi'E.

regularity in the form of granules in the light substance. The rows composed
of the bright substance vary greatly in their width. Sometimes a line of it
is as broad as the light substance ; or the shining substance may very much
siirpass the light one in breadth ; or a broad line may be sj^lit in the center
by an exceetliiigly naiTOW light line. In other words, the bright substance
varies greatly in its amoimt in relation to the light sul)stance.

When we come to use higher powers of the microscope, we iind that each
shining line is composed of a large number of square, cylindrical, or prism-
shaped pieces, which are the sarcou.s elc-
D mcniH of Bowman. (See Fig. 118.)

We also see that the light layer between
the rows of sarcous elements is traversed
by extremely delicate grayish filaments,
connecting all the rows within a muscle-
fiber. When the sarcous elements are
separated, so as to render the light inter-
stices between them visible, we again see
the gi'ayish filaments connecting the sar-
cous elements in a transverse direction.
Lastly, we see that all the interstices be-
tween the muscle-fibers are traversed by
delicate gi'ayish threads or spokes, con-
necting the adjoining muscle-fibers, and
also connecting the sarcous elements with
the granules present between the fibers.

From this it is evident that the mi-
nute structure of the fresh muscle of the
lobster is reticular. The nodulations of
the reticulum correspond to the sarcous
elements, and vary gi'eatly in size, while
the rectangular connecting fibrillte always
are very delicate.

All observers agree that the sarcous
elements are the active agents in mus-
cular contraction, because they are the
formations that change their shape and

Fig. 118. — Muscleof Lobster.

A, luuscle-fiber with single row.s of
sarcous elements; B, mnscle-liber with
(Uvidcd rows of sarcous elements ; C, sin-
gle torn fil)rilla, comi)08etl of divideil rows
of sarcous elements ; X», single flbrUla
without distinct structure. CD, features place during the contraction of the muscle,
from specimens preserved in chromic ^^iWe the intermediate light spaces are
acid solution. Magnified 1200 diameteis. ^., t -i

filled With a non-contractile liquid.

In order to bring out more perfectly the structure of muscle than could l)e
done in its natm-al state, I used, with success, a one-half per cent, solution of
chloride of gold, which is known to stain li-sdng matter \'ioiet.

I also tried the fi-eezing of the muscle by means of rhigoline-spray, in
order to cut the sections more easily and perfectly. But this changed the
texture, at times even completely destroying it, and I was compelled to resort
to other means. Here I may state that I suspect the peculiar condition of the
muscle discovered by Cohnheim, and pre\'iously mentioned, may have been
caused by fi-eezing. I did not succeed in obtaining those peculiar fields,
described by him, in transverse sections of the muscle of the ox, made while
the tissue was slightly frozen.

The next re-agent which I used was a one-half per cent, solution of

M r 'SCI. /•;- TISSUE. 277

chromic aci(i, whidi is known to preserve and harden living matter, lint not
to destroy its eliaracter or otherwise injnre it. Tlie results with tlie chronii*-
acid specimens were fouiul to i)e the same as those oliserved in the fresli
muscle. Here, too, the alternating layers of sarcous elements and the inter-
stitial layers were i)lainly recoj^nized. The rows of sarcous elements varied
greatly in breadth and form. If we tease a chromic acid specimen, we
obtain delicate longitudinal fibrilhe, because we break the transverse connec-
tions— the filaments of living matter which unite them together. Such an
artificially isolated fil)rilla may appear beaded, as was asserted by Th.
Schwann, or it may exhibit a nearly uniform w^idth throughout its entire
length, or the entire fibrilla may appear bright and homogeneous, and show
no trace of any difference in its optical properties in any part. This can be
explained by the fact that the sarcous elements within the muscle-fiber may
coalesce, or approach each other so closely that the intermediate light sub-
stance becomes invisible. We may explain the beaded condition of the
fibrilla either by saj-ing that the living matter produces a solid square piece,
— the sarcous element, — which above and below is hollowed out and incloses
the interstitial liquid, or by saj-ing that from both edges of the sarcous ele-
ment connecting filaments run to the neighboring sarcous element.

In a longitudinal section of a muscle-fiber, we not infi-equently meet with
oblong solid masses of a highly refracting nature, which are termed by the
authors, the nuclei. That such formations are present, not only on the sur-
face of the muscle-fiber, but also in its interior, is best demonstrated in trans-
verse sections, where, in the center of the fiber, we almost invariably observe
a more solid mass, with stellate offshoots which subdivide the muscle-fiber
into smaller fields. The presence of these large bioplassoit masses within the
muscle-fiber has a close connection with the history of the development of the
muscle. Similar formations do, however, occur in the muscles of mammals.
I have especially observed globular or oblong bioplasson masses in the center
of the muscle-fiber of the ox. In making transverse sections, these masses
are very liable to fall out, or, perhaps, be drawn out by the razor, leaving an
empty space behind. This gives the incorrect impression that the muscle-
fiber is hollow in its center.

Every muscle-fiber in mammals is known to be ensheathed in an extremely
delicate, firm, so-called elastic or hyaline membrane — the sarcoIem»if(. This
layer is present around the muscle-fibers of the lobster also.

The statement of E. Briieke, which has gained general assent, that the
sarcous elements are possessed of a double refracting power, is, I am con-
vinced, incoiTect ; at least, my own observations on the muscle of the lobster
with polarized light are not in accord with this view. I made a large number
of observations on specimens prepared in different ways, and also with perfectly
fresh specimens, moistened with a drop of the blood of the animal, and could
only obtain the phenomena of polarization in specimens of some thickness.
In every case when the specimen was very thin, and allowed the light to pass
tlirough it freely, there was no evidence of polarization. W. Kiihne (1 864)
failed to obtain polarization with the amoeba, and my observation with the
muscle-fiber of the lobster coincides with his.

It is Doyere's and Kiihne's discovery that the motor nerves, which control
the action of the muscles, never enter the muscle fibers, but terminate on
their surface, generally in the form of hiUs, the so-called motor hills. I have
observed similar formations in the muscle of the lobster, and, further, I have

278 MUSCLE-TISSUE.

observed a direct connection of the bioplasson of the motor hill with the
adjacent sarcons elements by many delicate grayish filaments of bioplasson
Tims, it becomes intelligible that the influence of the motor nerve may be
transmitted to a number of sarcous elements, from which it may spread
toward the points of the fiber and produce contraction.

As a result of these iHrestigations, I am led to the eonelusion tJiat the striated
museJe of the lobster is constructed on the same plan us the striated muscles of the
highly dcreloped mammals. It is a formation of livimj matter of a reticular
structure, the jyoints of intersection heing the sarcous elements, the means of
connection being delicate filaments extending in a longitudinal and transverse
direction.

IX.

NERVE-TISSUE.*

NERVE-TISSUE is composed of living matter, seen either as
an extremely delicate reticulum, or as apparently homo-
geneous filaments — the axis-cylinders. The reticulum is of a
uniform ^ddth, without well-marked points of intersection (see
page 128, Figs. 42 and 43), as seen in the gi'ay substance of the
brain and the spinal cord. In the reticular bioplasson, formations
are imbedded, which bear resemblance to nuclei, with distinct
walls and larger branching bodies, usually nucleated and reticu-
lar in structure — \t.z.: the ganglionic elements. From the retic-
ulum of the gray substance, and also from that of ganglionic
elements, somewhat thicker filaments emanate, — the axis-cylin-
ders,— which are the essential part of the structure of nerves.
The axis-cylinders, as a continuous formation, pervade aU tissues
of the body except the horny epidermal tissue, and serve for
the transmission of either sensory impressions from the peri-
phery to the center, or motor impulses from the center to the
periphery.

Nerve-tissue, as such, is destitute of blood- and lymph-vessels.

* This chapter will be found more deficient in histological facts than, per-
haps, any other of the book. The reason is that I have not as yet given verj-
much time to the study of nerve-tissue, this being the most unsatisfactory and
discouraging portion of histology. I prefer, therefore, to be incomplete in
this matter until I am able to make positive assertions, based on personal
observation, instead of relying too much on what others have said. The par-
ticulars that I shall give concerning the architecture of the brain I have
taken from the ingenious publications of Th. Meynert.

280 NERVE-TISSUE.

It is only the accompaii\ing and ensheathing connective tissue
which carries vessels.

In order to facilitate the study of the nervous system, it is
convenient to subdivide it into three main portions, aU of which
torm one continuous mass of tissue — /. e., the central portion,
the conducting portion, and the terminal portion.

1. Nerve-centers.

In the brain and the spinal cord, it is only the gray sub-
stance which can be called nerve-center, as the white substance is
composed of conducting nerves. The ganglia of the sjTupathetic
nerves may also be considered as central organs.

(A) Brain. According to Th. Meynert,* the gray substance of the brain
may be ciivided into four groups :

(a) The uppermost mass of gi*ay matter, fi-om which the entire white sub-
stance of the brain takes its rise, is the superfiviaJ i/ray .s«&.s/r/»<r of the cerebral
lobes — the cortex cerebri ;

(b) Collections of gi-ay matter are the (jaiujUa of the cerebrum — the corpus
striatum, the three members of the lenticular nucleus, the thalamus opticus,
and the corpora quadrigemina ;

(c) The tubular </rai/ matter, which invests the cavities of the brain as a
direct prolongation of the gi-ay substance of the spinal cord, traceable through
the fossa rhomboidalis, the aqueduct, the middle ventricle, into the tuber
einereum and the inf undibuhim ;

(fl) The grai/ sub.^-taiiee of the cerebellum, an-anged partly in layers, partly
in central aggi-egations, and in connection with the gi'ay formations of the
caudex cerebri, which are traversed by the medullary substance of the cere-
bellum.

The gi-ay masses are connected by means of fibrous tracts of the white
substance. The gi-ay cortex of the brain receives all the sensory inipressions
fi'om the outer world, and from it arise the motor impulses, communicated to
the motor nerves.

The medullary or white substance of the large hemispheres of the brain —
the corona radiata — fiu-nishes the routes of this si/stem of projections of the
first order ; and, moreover, this system is connected by bundles of nerve-fibers
with the cerebellum. The fibers of this projection system take mostly a radi-
ating com-se ; additional formations of this system are the commissiu-es in the
corpus callosum, which connect the corresponding portions of the right and
the left side, and the systems of association, which connect different regions
of the cortex in one hemisphere.

The ganglia of the cerebrum interrupt the projection system of the first
order, and in them a reduction of the number of the fibers of this system

~ " A Manual of Histolojrv," bv S Strieker. American edition, 1S72.

XFJiVK-TISSUK. 281

takes pliit'o. Tlic buiidlos of iii'rvi'-(ilK>rs, loaviiif^ i\w {^aiiKlia ami ontciiii^;
the eentnil tiilmlar \ivi\y investment of tlie brain, are eonsulered as tlie i>r<>-
jcction si/strni of the siroml order. This system is composed of two j)ortions.
One for the impulse of voluntary muscle action, arises from the corpus
striatum and the ntu'Ieus lenticularis, ])enetratiiif^ the i>t(liiiiciiliis cruris
cerebri; the other ]>orti()n is tlu' rout(^ of reflex motion, and takes its oriffin
from tlie tiialanius opticus, thi^ cor2)ora quadrif^emina. and the corp. f^eniciila-
tum internum, runnin<j into the tci/ninitiiin cruris cerebri.

The tubular ^ray nuitter j^ives rise to the ])eripheral nerves, which are
gi'eatly increased in numl)er, as compared with their reduction in the ganglia.
The perii>heral nerves represent tlie projfctioii system of the third order. The
accumulations of nerve elements in the tubular gray matter are termed its
nuclei, and this gi'ay matter itself lies bare on the base of the brain in the
lamina perforata posterior and the iufundibulum.

The cerebellum is independent, to a certain degree, of the projection
systems of the brain, though connected by the crura cerebelli with the cortex
cerebri, and jn-obably by the crura cerebelli ad pontem. It connects with the
spinal cord through the fasciculi gi-acilis and cuneiformis and the rcstiforra
bodies.

The iiieduUa oJ>lon</(it(i connects the brain with the spinal cord ; in this
formation the projection system of the second order is reduced to its simplest
form, as observed in the spinal cord. Both halves of the medulla oblongata
are connected by the pyramidal decussations, and both contain a number of
gray nuclei, the superior and inferior olivary bodies and the nucleus of the
pjTamis.

The eortex of the hroin has a common form of stratification, from which,
however, deviations are found in the occipital extremity, in the cortex bound-
ing the fossa Sylvii, in Amnion's horn, and in the olfactory bulb.

There are five strata of the cortex cereVm in man, which are as follows :

(a) The most superficial layer, which consists mostly of connective tissue,
and of a few small ganglionic elements and delicate nerve-fibrillie ;

(h) The second layer is marked by a large number of small, multipolar
ganglionic elements ;

(c) The third and broadest layer contains multipolar ganglionic elements,
decidedly surpassing in size those of the second layer. Their shape is either
pyramidal or fusiform, with the longitudinal direction vertical to the brain
surface. Their upper projection divides into a delicate reticulum ; the lower
passes without division toward the white substance ;

(d) The fourth layer contains small globules, with very delicate offshoots :
these, possibly, may be only connected with the sensory nerves ;

(e) The fifth layer holds spindle-shaped ganglionic elements, which lie
parallel to the surface of the brain, and have undivided offshoots. Meynert
considers them to be the intercalated cells of the system of association.

In the occipital extremity there are eight layers ; the third typical layer is
wanting, l)ut the gi-anular formation is composed of three layers. In the
cortex, bounding the fossa Sylvii, the fifth layer is markedly developed, pro-
ducing the claustrum. The cortex of the Ammon's horn has no gi-anular
layer, while the motor elements of the second and third tyi)ical layers are
very abimdant. The cortex of the olfactory bulb in its upper portion is cov-
ered with a white layer, and exhibits from below upward : a layer of non-
medullated nerve-fibers, a layer of the glomeruli olfactorii, a layer of

282 NERVE-TISSUE.

spiiidlo-shiiped fjaiiglioiiie elements, and a layer of gi-anules, the fibers between
which unite with those of the uppermost white medullary layer.

The Orif/iu of the Cerebral Xerres. As before stated, the tubular ^'ay
matter, which is located around the aquseductus Sylvii and extends backward,
connecting with the floor of the fourth ventricle, gives rise to the cerebral
nerves. In this gray matter we find groups of multipolar ganglionic elements,
which are known to be the nuclei of the nerves. There are also exceptional
formations found in the tracts along the anterior pair of the coi-pora quadri-
gemina, which consist of very large globular ganglionic elements. These con-
stitute the sensitive roots of the trigeminus. Similar formations are found in
the anterior nucleus of the root of the auditory nerve. Brown and black pig-
ment gi-anules are present in the substantia ferruginea of the fossa rhomboid-
alis and in the substantia nigra of the peduncuhis cerebri. The nucleus of the
hypoglossal nei-ve has very large ganglionic elements and a reticular forma-
tion, produced by a close combination of layers of the gi'ay and white sub-
stance. In the medulla oblongata such formations occur : in the pyramis, in
the fasciculi restiformis, gi'acilis, and cunciformis.

The olfactory rierre arises fi-om the olfactory bulb ; its external and larger
tract is connected with the g\Tus uncinatus or subiculum coruu Ammonis ;
its internal tract connects with the frontal extremity of the g^Tus fornicatus,
and its middle tract with the head of the corjnis striatum.

The ojitic nerve very probably starts from several nuclei, one of which is,
perhaps, the anterior paii* of the corpora quadrigemiua (Corp. bigem. super.).

The motor ocidi and trochlear nerve spring fi-om a cylincb-ical group of ele-
ments below the aquseductus Sylvii, near the median line. This nucleus, by
means of nerve-bundles, is in connection with the corpus striatiim and the
corpus bigem. superius.

The trigeminus nerve has several nuclei. The upper sensitive nucleus is
composed of groups of ganglionic elements along the tegmentiuu of the ante-
rior pair of the corpora quadrigemina ; the middle sensitive nucleus is located
below the upper one ; the under sensitive nucleus exists in the medulla
oblongata, and is traceable into the posterior column of the spinal cord. The
motor root of this nerve has its nucleus in the fossa rhomboidalis, extending
anteriorly to the aqufeductus SyUdi.

The abducent nerve originates fi-om a nucleus in the anterior portion of
the fossa rhomboidalis, and is in connection with the deeper situated nucleus
of the facial nerve.

The facial nerve originates from three roots arising fi-om a nucleus in the
depths of the floor of the fourth ventricle, where large ganglionic elements
with bulky offshoots are seen.

The auditor;/ nerve has its nucleus in the floor of the fossa rhomboidalis,
extending from the median line toward the pedunculi cerebelli, and gaining in
thickness as it advances. The median portion is the inner acoustic imcleus,
which may be divided into three parts. The broad outer portion has large
pyi'amidal ganglionic elements. An anterior nucleus is located at the side of
the peduuculus cerebelli.

The fflosso-pharipti/eal and vaf/us nerve arise from one common nucleus, the
anterior portion of which, reaching the internal acoustic nucleus, belongs to
the glosso-pharyngeal nerve, while the posterior jjortion, in the ala cinerea of
the fossa rhomboidalis, constitutes the vagus.

The spinal accessory nerve originates partly from the nucleus of the vagus.

xh'/nh-Tissrj:. 283

partly from ii coluiiiiuir formation, clost-ly coiiiicctcd with tho nm-h-uB of the
vagus ami traci-abli' into tin- aiitf-rior column of the spinal <"or<l.

Tin- lii/i)iK/l(tss(il iirrrr has its uuclcus in the posterior i)oi-tion of the fossa
rhomboitlalis, elose to the median line. There is also a diroet passage of
fibers from the erus cei'eliri into the hyi)oglo8sus byway of the raphe.

(JiJ Grai/ tSiihsfdiire. The gray substance is the only nerve-
tissue found in the l>rain of the h)wer vertebrates. Here, instead
of jraiio;lionie elements, nuelei are present, which, especially
arouiul the ventricles, collect in regidar rows, representing in its
sini})lcst relations the bioplasson of the nervous center. (See
Fig. 118.)

The presence of connective tissue in the gray substance is
un(iuestional)le, as it is the carrier of the numerous l)lood- vessels
of the gi'ay substance. The finest ramifications of connective
tissue, however, have not T)een discovered, but are still the sub-
ject of animated controversy amcuig histologists. It seems that
the finest offshoots of the ganglionic elements, producing an
extremely delicate reticulum, fii'st discovered by T. GfrlficJi,
deserve to be classified among ner\'ous structures, inasmuch as
in this reticulum there is no indication of a basis-substance — an
essential part ot all viuieties of connective tissue. It may be that
connective and nervous tissue blend with each other so intimately
that an accurate determination of either of them is impossible.

The Ijlood-vessels of the gray sulxstance are characterized by
the presence of a hTuph-sheath. His was the first to draw atten-
tion to this fact. According to him, each blood-vessel is en-
sheathed by an adventitial coat of endothelial structure, and the
space between the tube of the blood-vessel and the investing tube
of the lymph-vessel varies greatly in -wddth. Boll's ^^ew con-
cerning the lymph-sheath is somewhat different.

The cortt'X of the cereheJhon is composed of three layers. The
outermost is called the yrti!/ layer, and exhibits, with low powers
of the microscope, a delicate gi-anular appearance, which, with
high powers, proves to be a reticulum, considered l)y histolo-
gists to be a connective-tissue formation. Within the reticulum
there are scanty, small, branching ganglionic elements ; on the
innermost portion we notice fibrous tracts, in a direction par-
allel to the surface. The middle so-called cell-hujer contains
large, branching, and nucleated ganglionic elements, mostly pear-
shaped, standing in a vertical or oblique dii-ection to the surface.
These bodies, in honor of their discoverer, ai'e termed Purkinje's
cells. From the outer pole of each corpuscle originates an offshoot,

284

NERVE-TISSUE.

which freely bifurcates and sends its branches into the outer gray
layer. From the inner pole arises an offshoot, which, without
ramifications, traverses the granular layer and runs into the

j?-

''' ' " '"''' ^1

^'■■\-m:- 1

'JiS^-

Fig. 118.— A^cterior Lobe op the Brain op a Tree-frog.
Sagittal Section.

/. investing slicath of connective tissue; J?, rows of nnclei; T', ventricle, with e.ndotliel-
ial investment ; -V, bundle of meduUated nerve-fibers. Ma^ified 50 diameters.

white siibstance. The inner so-called granular layer is composed
of heaps of small globular bodies, mostly of a high degi-ee of

XETiVE- TTSSr'K. L'S.')

ivfraction and siinilar to thr Ixxlics f(»iiii«l in tlie granular layers
of till' ri'tina. Thoir nature is unkn(»wn.

Tlu' h ijixtpliysis crrrbri exliihits two lobules, which are soparatod from eacli
other by a number of venous blood-vessels. The posterior small portion is
an eloiifjation of the infundibulum, and ])robably bclonf^s to the nervous struct-
ures. The anterior larf^e lobide is a glandular formation, and, as Von Mihal-
kovits has demonstrated, was originally a club-like prolongation of the oral
cavity of the embryo.

The ))iiir(il t/Uind is attached to the brain by means of connective tissue.
and has no nerve elements in its interior. It is composed of alveoli, contain-
ing corpuscles in a reticular aiTangement. In the middle portions, the alve-
oli are filled with the renbrdi .sand, consisting of globular or mulberry-like
concretions, as a rule exhibiting a concentric striation.

The organic material in these bodies is infiltrated with carbonate of lime
and phosphate of magnesia.

The (/)■<(!/ sKhsianre of the spinal cord is in the ceuter through-
out the whole length of the cord, reaching the greatest size in
the cervical and the lunil)ar portion, where the largest nerves for
the extremities arise. The general form of the gi"ay suljstance in
trauverse section resembles a butterfly, the two anterior larger
mugs being distinguished from the posterior smaller ones by a
shallow depression. Each half of the gray substance represents
a column, and the two are connected by commissures travers-
ing the so-called medullary cone or commissure leaf (Markblatt,
Commissurenblatt). (See Fig. 119.)

Each gi'ay column exliibits a large anterior, or motor, horn,
and a smaller posterior, or sensitive, horn. In the outer portion of
the antei-ior horn we find very large motor ganglionic elements,
varving greatly in size and shape in different portions of the
spinal cord. In some portions of the postei-ior horn ganglionic
elements are absent, and in their place accumulations of nuclei-
like bodies are observed. The posterior horn, from its soft con-
sistence, bears the unnecessary name, " gelatinous substance,''
which name by some histologists is given to the commissural
portions in the neighborhood of the central canal. • The latter
portion is also called the central ependjona thread, or the central
gray nucleus. The central canal, a prolongati(jn of the cerebral
ventricles, is lined by a columnar endothelium, which in youth
shows distinct ciHa, while in older individuals the cilia are not so
plainly mai'ked.

fCJ Ganglionic Elements. The ganglionic nerve elements ('' gan-
glion cells ") are scattered throughout the gray substance of the

286

NERVE-TISSUE.

brain and spinal cord ; they vary greatly in size and shape. The
smallest of these bodies are kindred to those formations of the
gray substance considered as nuclei. Many of them are doubt-
ful in their nature — f. i., the " cells of Deiters," which by some
observers are considered as nervous, l)y others as connective-
tissue, corpuscles. The larger ganglionic bodies exhibit a dis-
tinct angular or fusiform shape, and give rise to nerve-fibers,
therefore are real nerve-centers. The largest ganglionic elements
are found in the lateral portion of the anterior or motor horn of
the spinal cord.

In the spinal cord, the groups of ganglionic elements are dis-

^^^M

cc-

/SC

PQ

Fig. 119. — Spinal Cord of Trog. Transverse Section.

AF, anterior longitudinal fissure ; PF, posterior longitudinal fissure ; TF, white substance :
A C, anterior comuiissure of the ^I'ay substance : MO, anterior or nuttor honi of tlie gray col-
umn, rich with ganglionic elements; SC, posterior or sensitive horn ; CC. central canal; PC,
commissure layer, with fibers of the posterior commissure ; MR, anterior or motor roots; PB,
posterior or sensitive roots of nerves; MN, intervertebral ganglion, the connection with PR
broken ; V, pia mater, hokling a bloodvessel. Magnified 50 diameters.

tributed in the following way : In the anterior horn we notice
three groups of ganglionic elements, not distinctly marked
throughout the whole ; the largest group lies in the lateral por-
tion ; a smaller group in the anterior portion, near the greatest
protrusion of the anterior horn, and a third group, the smallest,

NKinj-j-Tissi-t:.

287

lU'sir tlic iiicdiiiu line. A fourth ^I'Oii]) of «iaiijilioiiic clciiicuts,
roustitiitiii^' the rolidtnis of Clarke^ is found only in the tlioi-acic
portion of the spinal cord, in the foremost part of the posterior
liorn, near tlie ])()sterior eoininissure. In the posterior horn th(^
ji:an^lionic elcnu'uts are always snndl, scattered, and with com-
paratively few offshoots. The illustration is taken from the
third fjfroup of the anterior horn. (See Fig. 120.)

The ji-anglionic elements are bioplasson formations, which,
aecordino- to tlic number of offshoots, are termed unipolar,

Fig. 120.-

-GrANGLIOXIC ElEMEXTS FROM THE ANTERIOR OR MoTOR

Horn of the Spinal Cord op a Child.

U, uniiiolar; B, bipolar; T, tiipol.ir; Q, quailiipolar ganglionic element; H, gray sub-
stance, containing small, sliining nuclei, and a number of axis-cylinders; CL, capillarj-
blood-vessel, longitu<linallj-, CT, capillary blood-vessel, transversely, cut, each surrounded
bj- the lympli-sheatli. Magnilied (300 diameters.

bipolar, tripolar, quadripolar, or multipolar. The number of
offshoots is in close relation with the size of the corpuscle. A
light space is often found around the ganglionic element ; this is
the so-called "periganglionic space," which, in all probability, is
artificially produced by the shrinkage of the neighboring tissue.

288 XERVE-TISSUE.

The reticular structure of these bodies was first described by
C, Frommann, in 1867. This reti(;ulum is usually very distinct,
especially when the formations of nuclei, nucleoli, and nucleolini
(L. Mauthner) are well marked. The reticidar structure is not
peculiar to these bodies, but is one of the general features of all
bioplasson. The offshoots of the ganglionic elements are of two
kinds: the broad, so-called 7»-ofo;>?«.s»</c of shoots of Dei fers, and
the narrow, axis-rijlinder of shoots. Of the former, we know that
they connect neighboring elements and branch out into the
gray suTjstance. where they divide into an extremely delicate
reticulum, first described by T. Gerlach. This author further
asserts that the ganglionic elements of Clarke's columns, and
perhai)S those of the posterior horns also, have no other than
branching offshoots. The narrow axis-cylinder offshoot takes
a more or less straight course, and enters the white substance
without ramifications, thus being a future nerve-fiber. Axis-
cylinder offshoots arise also from the gray substance, without
any connection with ganglionic elements.

M. Schultze and others maintain that the axis-cylinder has a
delicate fil)riUated structure, and that the fibrillse spread in the
body of the ganglionic element after the manner of a fan. This
assertion is based upon observation of teased specimens, and
should be cautiously received. I have often studied the brain
structure of freshly killed rabbits, both with and without the
addition of an indifferent liquid, and could never discover any
fibrillated structure in the axis-cylinders. Both the broad
axis-cylinders and the broad offshoots have a delicate reticular
structure, like that seen in the ganglionic elements themselves.
The finest axis-cylinders are apparently solid or slightly vacu-
oled. In the gray substance, especially in young animals, many
axis-cylinders exhibit varicose enlargements, which are consid-
ered by histologists to be post-mortem appearances. This,
again, is an assertion which I must contradict, as 1 have fre-
quently observed such enlargements in fresh specimens (see page
129, Fig. 43). I must also contradict the assertion of histologists
that meduUated nerve-fibers arise directly from ganglionic ele-
ments. These bodies are present only in the gray matter, where
no medullated nerve-fibers exist, but only bare axis-cylinders ;
ob^-iously. therefore, the axis-cylinder, emanating from the gan-
glionic body, must run for a certain distance without a myeline
investment.

Verv little is known regarding tlie course taken by the nerve-

NKini'JTfssrE.

2ftn

tilnTs within the i?ray sultstancc of tlic s]>iniil cord. The iici-vc!
of the aiitcrioi" oi' motor roots oritrinatc from the motoi" pin^lia

Fitf 121 — Ajntlrior Portion of ihe Spin vi Cord
OF A Child. Transverse Section.

!•". anterior lon]crituilinal fissure ; P, pia mater ; TP, white substance, traversed bj' oftslioots
of tlic pia mater ; O, passage of the anterior or motor nerves through the white substance ; G,
gray substance, containing X, ganglionic elements; C, central canal, containing granular
coagulated cerebro-spinal liquid. Magnified 150 diameters.

a small number of nerve-fibers reach the motor roots from the
white substance. From the reticulum of Gerlach nerve-fibers
19

290 / NERVE-TISSUE.

arise which reach the opposite horns, par-tly throuj2:h the anterior
commissure, partly by runninjif u])ward to the medulla oblongata,
where they decussate. The posterior roots also arise from two
bundles, one of which traverses the posterior commissure. Ac-
cording to Gerlach, it is also probable that from the reticalum of
the posterior horn nerve-fibers originate, which in this horn and
in the white substance take a centripetal course. The structure
of the posterior horn is considered to be mainly connective tissue,
especially in its gelatinous portion.

(I) J The wliite suhsfaiice of the spinal cord, as well as that of
the cerebrum and cerebellum, is composed of meduUated nerve-
fibers, which in the spinal cord run in a longitudinal direction
and furnish the outer investment with its nerve supply. This
substance borders on the anterior and posterior longitudinal
fissure, and is pierced by niimerous offshoots of the pia mater,
which divide and subdivide the nerve-bundles into larger and
smaller groups. (See Fig. 121.)

The anterior and posterior roots of the spinal nerves also pro-
duce smaller fissures in the lateral portions of the white sub-
stance, the sulcus lateralis anterior and posterior, by which the
white substance is divided on either side into an anterior, a lat-
eral, and a posterior cord. In the thoracic and cervical portions
of the spinal cord the posterior part is again divided into halves,
the middle division of which is termed the dehcate cord, and the
larger lateral portions the wedge-shaped cords.

The medullated nerve-fibers of the white substance vary
greatly in size. The coarser offshoots of the pia mater send lat-
eral prolongations between the nerve-fibers, every one of which
has a delicate investment of connective tissue — the perineurium
internum or neuroglia. According to Gerlach, this connective
tissue is rich in elastic substance, and furnished with small glob-
ular or angular nuclei, but has a relatively scanty supply of
blood-vessels.

In transverse sections of the white substance, we especially
recognize the medullated nerve-fibers by their graceful ensheath-
ing reticulum of connective tissue and their central, bright axis-
cylinder, which readily takes up the carmine stain. (See Fig.
122.)

Each nerve-fiber is provided with a delicate outer investing
membrane — the myeline sheath, or Schwann's sheath — which
holds flat, oblong (in the transverse section spindle-shaped)
nuclei. Former ol)servers denied the existence of this sheath :

Nh'in'h'-rrssuE.

21)1

but (it'i-liicli (•((iH'ludcd that it must be present, and I positively
maintain its oxistenee. The next hiyer is the mijcline invcHtmcnt^
which, in thin sections, is invai-iably destroyed. In its phiee, a
dt'licatc, knotty rcticultim is visibh', to tlic existence of whicli
Kiihne and Evvahl * tii-st (bvw attention. These observers ehiim
that the retieuhim in tlie myeline layer is horny or keratoid,
because it resists (bticstion witli ])epsine and tripsinc. They also
traced in the gray sul)stance a similarly resistant reticulum. In
the meshes of this reticulum the myeline is contained. The mye-
line investment in some nerves is very narrow, and in others
conii)letely wanting-. The next layer is a delicate sheath — the

Fig. 122.— White Substance op the Spinal Cord
OF A Child. Transverse Section.

PE, connective-tissue offshoot of the pia mater — the external perineurium; P/, lateral '
conuective-tissue offslioots aroiinil the nerve-fibers — the internal peiineurium ; M, oozed-out
nij-eliue investment, with inclosinj^ myeline sheath; A, axis-cylinder, with inclosing axis,
cylinder sheath. Magnified 600 diameters.

axis-cylinder sheath., discovered by L. Mauthner — similar to the
myeline sheath. The center is occupied by the bright, homo-
geneous-looking, usually roundish axis-cylinder, from which
delicate radiating spokes emanate and go to the axis-cylinder
sheath.

In longitudinal sections the axis-cylinder is plainly visible
only where the investing sheaths are stripped off, but where the

Verliandluni^eii der Heidelberger Gesellsehaft, 1 S7(>.

292

NEHVE-TISSUE.

sheaths are preserved and the myeline is absent, afaint trace only
of the axis-cylinder is discerned. We recognize the myeline
sheath with its oblong nuclei ; at pretty regular intervals it sends
out transverse septa through the myeline investment, the signifi-
cance of which will be spoken of later. The reticulum of the
myeline sheath is very distinct where the myeline has oozed out.
The axis-cylinder sheath can be recognized here and there,

though it is often verv diffi-
^^ '

cult to distinguish it from
the stretched myeline sheath,
which may lie close to the
axis-cylinder. (See Fig. 123.)
fEj The Connective-tissue
Investments of the Brain and
the Spinat Cord. The brain
and spinal cord have three
membraneous investments —
the dura mater, the arach-
noidea. and the pia mater.
The spaces between these are
filled with a varying amount
of cerebro-spinal liquid. The
space between the dura mater
and the arachnoid is called
the subdural space ; that be-
tween the arachnoid and the
pia mater bears the name suh-
arachnoidal space, and is tra-
versed by trabecidffi of con-
nective tissue, uniting the
membranes. In the spinal
canal this space is subdi\'ided
into halves by the Lig. den-
ticulatum, and contains the
of the brain. A thii'd space

dS

Fig. 123. — White Substance of the
Spinal Cord of the Horse. Lon-
gitudinal Section.

A, axis-e.vlinder; AS, axis-cylinder sheatli;
X, nucleus of the myeline slieath : MS, mye-
line sheath, with oblong nuclei. Magnified 600
diameters.

large blood-vessels at the base
between the pia mater and the surface of the brain may be pro-
duced artificially by the injection of li(iuids from without ; it is
called the epicerehrtd space.

The dura mater of the skuU represents the periosteum of the
cranial bones, while in the spinal canal there is a perio.steal
investment of the vertebrte, in addition to the dura mater. It
is composed of very firm, dense interlacing fibers of connective
tissue. Its outer layer is well pro\'ided with lilood-vessels enter-

NKRVK-Tissri:. 293

iiiji' tlic skiill-l)ones ; while tlie inner layer, that whieh alone
forms the dura mater of the spinal cord, has a comparatively
scanty su])ply of hlood- vessels. The inner surface of this mem-
V)rane is lined with a delicate layer of endothelia.

The anuJnioidcd is composed of much more delicate l)undles
of connective tissue than the dura mater (see Fig. 55, page 160),
and ])rol)al)ly contains neither hlood- vessels nor nerves. Both
its surfaces are covered with endothelia. It sends numerous
trabecuLi' in an obli(iue direction into:

The j)iii iiKifcr, which is also constructed of delicate inter-
lacing l)undles of connective tissue and sui)plied with nmnerous
blood- and lymph-vessels and nerves. The prolongations of the
pia mater into the brain and spinal cord convey mainly capil-
hu-y l»lood- vessels, as the division of the arteries into capillaries
takes ])lace Ix'fore their entrance into the nerve-centers. The telae
choroidea3 are freely vascularized formations of the pia mater ;
their blood-vessels are coiled in bundles, and produce the lobules
which are covered with lai-ge, j)artially ciliated, endothelia, often
containing pigment and fat-granules.

fFJ The GangJia. Nerves of the cerebro-spinal system are
provided in certain localities with spindle-shaped, or globular
or crescent-like, enlargements, the ganglia, which consist of an
accumulation of ganglionic elements, greatly varying in size,
and arranged either in rows or in clusters, which are more
numerous at the periphery of the ganglion than at its center.
The manner in which nerve-fibers are connected with the gan-
glionic elements has not yet been elucidated. Each ganglion
is eusheathed by a connective-tissue capsule, and divided by
septa of connective tissue into smaller portions ; sometimes
every single large ganglicmic element is inclosed l)y a connective-
tissue sheath, the connective tissue being always freely sup-
plied with blood-vessels.

The ganglia of the sympathetic nerve system contain smaller
ganglionic elements and numerous globular bodies, exhil)iting
the features of lymph-corpuscles or nuclei rather than those of
ganglionic elements. The ganglionic bodies are, as a rule, mul-
tipolar. In those of the frog the central axis-cylinder was found
to be suiTOunded by a delicate spiral fiber (Beale), which is also
considered to be an offshoot of the ganglionic element. J. Arnold
claims that the straight central fiber comes from the nucleolus of
the ganglionic body, while the spiral fiber originates from its
periphery. All these assertions have been contradicted, and need
further proof before they can be received.

294

NEBVE-TISSUE.
2. Nerves.

Nerves are thread-like formations of bioplasson connecting:
the nerve-centers with the periphery of the body. They are
of two kinds: first, those endowed with a myeline investment,

Fig. 124:. — Branch of the Motor Oculi Nerve of Man.

L, longitudinal, T, trausveise section of the bundle; PE, external i)erinoui'iuui ; PI,
internal perinenriuui ; 3/X, luj-eline investment; J, axis-cylinder; il/, transverse sections ol
muscle-fibers. Magnitied 600 diameters.

the medullated or white nerves; and secondly, those which
are without a myeline investment, the non-medullated or gray
nerves.

XKL'Vh'-nSSUE. 29.')

fdj M(>li<ll(ifi'il Xerr/'s. Tliese (•<)jnj)<)S(' tlic whito siihstiiiict'
of the l)i-:iin jiiid of the spinal cord, and all the nerves spring-inj;
from tlie hrain and the spinal cord, with the exception of the
olfactory and auditoi'v nerves. They invariably run thcii- whole
course without hranchiug'. The constituent parts of nH'dullated
nerves are best studied in specimens where, owing to a wavy
course of the nerves, the razor in cutting produces alternately
longitudinal and transverse sections. (See Fig. 124.)

We see that each nerve-bundle is made up of a varying number
of fibers. The bundle is surrounded by a somewhat broader layer
of fibrous connective tissue, the external perineurium., from which
arise delicate membranes of connective tissue, ensheathing each
single fiber; this formation has received the name of the infernal
perineurium. Both the external and internal perineurium are
provided with a lai'ge number of blood-vessels. Next, there is a
delicate hyaline layer with distinct nuclei, the niijeline sheath, or
sheath of Schwann. This sheath incloses a layer of a semi-fluid
fatty substance, the mi/eline or nerve-fat, or the white substance
of Schwann. At comparatively regular intervals the myeline
investment is traversed, according to L. Ranvier, by transverse
septa, which he found to be in connection with the axis-cylinder
sheath (Mauthuer), and closely related to the development of
the medullated nerves. The myeline investment is separated
from the central axis-cylinder by a delicate hyaline sheath, the
axis-cylinder sheath (Mauthuer). This incloses the central axis-
cylinder, which may be either round or oblong, and is the con-
ducting part of the nerve-fiber. In transverse sections this is
easily recognized from its bright, almost homogeneous, appear-
ance, while in longitudinal sections it is invisible if the myeline
be present, and only faintly visil^le if the myeline be absent.
Not infrequently we find two axis-cylinders in one nerve-fiber.
Together with the large medullated nerve-fibers in the same
bundles there are sometimes found fibers without and also fibers
with a very delicate myeline investment. The latter formations
probably belong to the sympathetic system.

The myeline is a fatty substance, differing from ordinary fat,
however, in both its optical and chemical characteristics. From
the fact that a delicate reticulum is still preserved in the space
between the sheaths of the myeline and that of the axis-cylinder
(see Fig. 123), and from the fact that fat is a product of living
matter, we may (*onclude that the myeline is, perhaps, produced
from only a part of the living matter, while the other part

296

NEBVE-TISSUE.

remains nnchang-ed in the shape of a reticnhim, or, still more
probably, the myeline originates in a manner different from that
of fat — viz., from the lifeless liquid contained in the meshes of
bioplasson. In specimens of medullated nerve-fibers the myeline
is often fonnd exuded from the nerves in the form of numerous
slightly refracting formations with a concentric striation, which
is e\ddently caused by a slow oozing and aggregation of the
myeline. (See Fig. 125.)

?r—^.

Fig. 125. — Myeline Drops, Oozed Out from the
Optic Nerve of a Bull.

V, buuclle of nieiUillated uerve-rtbers ; M, iii^-eliue drops ; F, fat-granules. Magnified
400 (liameters.

By staining fresh medullated nerve-fibers with a solution of nitrate of sil-
ver, the bundle was found to be covered \)y an endothelial coat. Each fiber
exhibits a series of marks, which coiTespond to the " annular constriction " of
Ranvier. The axis-cylinder at the point of constriction exhibits a number of
dark brown transverse lines (Frommann). Between every two constrictions
a transverse bar has been found, of a biconical shape, through the broadest
portion of which the axis-cylinder passes. Ran\'ier concludes fi-om these
facts that each section of the nerve-fiber is a imit, a tubular cell, filled with
myeline, like a fat-globule, which he terms the interanntdar m/iiient, with an
oblong nucleus in its investing membrane. The axis-cylinder, according to
this author, pierces a series of interannular segments without interruption ;
while Engelmann, on the other hand, claims that each interannidar con-
striction corresponds to an interruption of the axis-cylinder. This latter

XKh'VK-TrssTTE.

•J!>7

tissortioii is contrary to our iiU'iis of iiorve action iuid so is tho assertion of
otlior liistoloj^ists, that the axis-cyliiKlor is a fluid.

Ill jx'riplu'ral foniuitions of eonnective tissue — f. i., in the
t'emalt' l)rciist, tlic lU'niia of the skin, etc. — we often en<!ountcr
sinjfk^ nieduUated nerve-fibers, exhil)iting the eharaeteristic feat>-
ures just deseribed. Their d()ul)le contour is due to the presence
of the myeline sheath, and not to the refraction of the niyeline,
for the doulth' contour is visibk^ even when the niyeline is abseut.
The tinted appearance of medullated nerve-fibers is partly duo to

Fic. 12G. — Medullated Nerve-fibers of the Female Breast.

jy, liervo-tibers ; C, capillary bldod-vtssels ; F. fat-^dolmle with vacuoles. Magnlticd 00(1
diameters.

the presence of the oblong- nuclei in the niyeline sheath, and
partly to consti-ictions along the course of the nerve-fil)er, to the
presence of which Reniak, and recently Schmidt, drew^ atteutiou^
the nature of which is not yet understood. All these features
are marked characteristics of medullated nerve-fibers, in contra-
distinction to those of capillary l)lood-vessels. (See Fig. 126.)

In nerve-bundles no ramification of the fibers takes place, but
as they approach the periphery, either motor or sensitive, they
l)ranch very freely, and one fiber often splits into a number
of slightlv thinned branches.

298 NEBVE-TISSUE.

fbj Kon-mednlJated Nerves. These nerves have the appearance
of being bare axis-cylinders, destitute of a myelin e investment.
There are comparatively broad so-called Remak's fibers (1838).
in large numbers, in the sympathetic and in the cranial portions
of the olfactory and auditory nerves. These flljers exhibit on
their surface a number of oblong nuclei, and they have often a
delicate sheath, kindred to the axis-cylinder sheath of medullated
nerve-fibers, to which, probal)ly, the nuclei lielong. These
nerves are described as indistinctly fibrillar in structure, and
at certain intervals showing clusters of small, bead-like forma-
tions, giving rise to the so-called necklace appearance. All
nerves in the earliest stages of embryonal development are non-
medullated.

Besides these broad non-medullated nerve-fibers, there are
others which are narrower, scattered throughout the gray sub-
stance of the brain and of the spinal cord. They run in bundles
with the medullated nerve-fibers, and also with nerves of the
sympathetic system. Such fibers, which are bare axis-cylinders,
represent the origin of all nerve-fibers, even of the medullated, in
the gray substance. In many instances, the medullated fibers
become again non-medullated upon approaching the periphery of
the body.

With high amplifications of the microscope, some of the larger
non-medullated nerve-fibers show distinctly a delicate reticular
structure. Others exhibit a number of minute vacuoles in their
interior; still others, and these are the finest nerve-fibers, have
a homogeneous appearance and give no evidence of structiu'e.
<See Fig. 127.)

Many of the finest non-meduUated nerve-fibers show oblong,
varicose enlargements along their course, and bear the name of
varicose nerve-fibers. The varicosities are certainly not post-mor-
tem appearances, as they are visible in the perfectly fresh condi-
tion of nerve-specimens, as stated above.

3. Terminations of Nerves.

The manner in which the ultimate nerve filaments terminate
in the tissues and at the periphery of the body is known only in
part. There are two varieties, either terminations of medul-
lated nerves as such, or terminations of non-medullated nerves.
The latter are either continuations of originall}^ medullated

XK7n'j-:-TrssrE.

201)

norvos, wliicli luivc Itccoiiic (It'stitiitc of their iiiyt'linc invcstniciil
upon }H)})roa<'liiii^' tlic pciMphciy, or tlicy are iion-inedullatcd,
synipathetic nerve-fibers.

f<ij I'rnni)i((fion of McdulUtii'd Xervc-fihirs.

The motor hill of nerves controlling' the action of muscles (see
chapter on muscle tissue).

The tuctile corpnscJes of Merkcl in the we)) of the feet of
water-l)ir(ls, in the trunk of the pig, etc. These are finely granu-
lar, distinctly nucleated, glol)ular hodies, into which the axis-
cylinder penetrates, and which are located in the upper layers of
the dernui or in the epithelium — f. i., in that of the external root-
sheath of the tactile liairs. Sometimes two or more such corpus-
cles are attached to the niedullated nerve-fiber.

The tactile corpuscles of Meissner or Wagner are present in the
papillte of the derma of the skin, often below the level of the

Fig. 127.— Medullated and Non-medullated Nerve-fibers
FROM the Retina of a Bull.

S', mj'eline slieatli, with obloug nuclei and (S^) transverse septa. Tlio mj-eline oozed out.
iV, uon-medullated nerve-tibers, with varicose eulargeiueuts. MaRuilied 000 diajneters.

papillae, and especially numerous in the tips of the fingers and
toes; These are ovoid or globular formations, with transverse or
spiral striations and oblong nuclei arranged in the direction of
the striations. One or more medullated nerve-fibers enter the
corpuscle at one pole. Sometimes two or more such corpuscles
are clustered together ; but the way in which the termination of
the axis-cylinder is effected is unknown.

The bulbs of Krause are found in the conjunctiva, in the
mucous membrane of the floor of the mouth and of the lips, of
the soft palate and the tongue, in the glans penis and in the ch-
toris. They are ovoid or mulberry-shaped bodies, in which the

300

NERVE-TISSUE.

axis-eyliuder terminates as a knob. Longwortli fonnd them in
some eonjunctivie, but not in all, and saw their interiors filled
with nucleated corpuscles. Waldeyer considers these bodies to
be intermediate formations between the tactile and the Pacinian
corpuscles.

The corpuscles of Pacini (discovered by Vater in 1741) are
found in the subcutaneous tissue of the nipple, the pahn of the
hand, and the laliia majora, in the periosteum, the mesentery,
especially along the branches of the sympathetic nerve, and in
many other places. They are oval or pear-shaped bodies, com-
posed of numerous concentric strata, exliiliitiug; nuclei. The
medullated nerve-fiber upon entering this body becomes destitute

Fig. 128. — Terminal Plexus of Xox-medullated Nerves, bexeath
THE Epithelial Layer of the Corxea of a Bull.

X, uon-meiluUateil nerve-fibers, partly witli a deliiate reticular, partly with a lumpy,
structure: G, jranglionic enlargement; E, columnar epitUeUa, in top view. Magnified 600
diameters.

of its myeline, and terminates in a knob or a chain of gi-anides.
Sometimes two nerve-fibers pass into the corpuscle. The signifi-
cance of these formations is not understood.

(1)) Termination of Xon-medullated Xerve-fibers. The most
common termination of nerve filaments is a plexus, in which, as
a rule, ganglionic elements are found as nodidar points of inter-

xh'jn'h'-rrssT'K :m

se<'ti(>n. Sucli plcxifoi'iii tniiiiiiatinns ai'c seen in (lifffiM-iit local
itit's ])eiu'atli the i-pitht-lia, in the suldimcoiis tissue, and in the
connective tissue between the circular and longitudinal muscle-
layers of the intestines. (See Fi«;. 12S.)

The jth'xiis of Meissmr is located in the siil)iune<)us layer of
the intestine, and exhibits distinct ganjjlionic enlargements (see
chapter on alimentary canal).

The plexus of Auerhnch is found at the junction of the
two muscle-layers of the intestine ; it c<nitains nodular jran-
glionic bodies with numerous nuclei (see chapter on alimentary
canal).

The axis-cylinders, near their terminations, di\ade into ex-
tremely delicate tixis-fibrilhf^ (M. Schultze), which are sleudei*,
beaded filaments, representing the bioplasson reticulum in an
elongated direction. Their course in the cornea has been accu-
rately studied by W. Hassloch (see page 175, Fig. 67). They enter
a cornea-corpuscle and inosculate with its bioplasson reticulum,
e\ndently in the same manner in which they originate in the cen-
tral ganglionic element. Many fil)rillae simply pass through one
cor]^usele and enter another ; fibrillar have been also traced into
the bioplasson reticulum of the basis-substance. Terminations of
this kind are found in different connective-tissue formations; they
are not permanent, but may occur from a temporary enlargement
and elongation of reticular fibrillar connecting with former nerves.
As they are bioplasson formations, they may disappear by falling
back into the reticulum.

The finest plexiform terminations of axis-fibrillae are observed
in the walls of capillary blood-vessels, particularly in the cement-
substance between the endothelia (W. Tomsa and others). Such
plexus formations were found in the epithelia by Pfiiiger, Langer-
haus, and others, and it is still an unsettled question whether the
nerves terminate in the cement-sulistance between the epithelia,
or penetrate the epithelial bodies themselves.

Peculiar epitheli;d formations are the gustatory buds
(Schwalbe) and the olfactory cells (M, Schultze), the connecti(m
of which with nerve-fibers, however, is still a disputed point.
Veiy complicated formations are those of Corti's organ and of
the retina. The plates, the '' hair-cells,'' the rods and cones are
well known, but how the nerves connect with these is unsettled.
In the light of the bioplasson theory we may, at a time not far
distant, hope for new discoveries and new views.

302

NERVE-TISSUE.

Development of Nervous Tissue.

Very little is known in regard to the development of the nerve-
centers and the nerves. All observers adhere to the idea that the
nerve-centers are products of the outer or horny embryonal layer,
the epiblast. According to general biological views, this cannot
be correct. The nerves, being so closely allied to connective
tissue, are offspring developments from the middle embryonal
layer, the mesoblast. L. linger * maintains that the medullated
nerve-fibers of the ])rain arise from radiating tracts, in which the
cells are arranged in columns ; these columns first have a retic-
idar appearance and an investing membrane. He claims that
the reticulum of the myeline layer is produ('ed earlier than the
axis-cylinder ; that connective tissue and nerve- tissue may arise
from one and the same ceU, and that nerve-fibers or axis-cylinders
may come from certain portions of the reticidum.

Fig. 129. — Brain op a Human Embryo, Five Weeks Old.

P, {fray siib.stiiuce with numeroua nuclei ; A, axis-cyliiKleis ; C, capillary blood-vessels.
Magnilictl 600 diameters.

My own observations prove that the brain of a liuman embryo
five weeks old is composed of a bioplasson reticulum, whose
points of intersection with low powers appear to consist of gran-
ules. In this reticular mass niunerous nuclei are imbedded, and
tracts of axis-cylinders laid before even a trace of a medullated
nerve can be demonstrated. (See Fig. 129.)

This shows that the development of the nerves can never be
understood in accordance with the cell theory, inasmuch as there

* " Untersiichungeiiin»ev die Eiitwickhiiig der eentraleu Nervengewehe."
Sitzungsber. d. Wiener Akad. d. Wissenseli, 1S70.

XJ'JIi I 'K- TISSUE. :{0a

is iiothini!: to sn])]K>rt the assumption that nervous tissue ori<^i-
nates tVoni *' cells." rnciuestionaldy, there are lar^e nuisses of re-
ticular bioplasson in wliieh l»y a growth of living matter, chiefiy
in one direction, axis-tibrilhe originate, while the medullary
investment is a mueh latei- foi-ination. At first there is no trace
of ffany-lionic elements. We know that these elements make their
apjiearance only after the third month of intrauterine life. The
motor elements of the spinal cord particularly are first observed
during the third and fourth months, corresponding to the time
when the embryo begins to manifest signs of life. Further, the
ganglionic elements cannot arise from cells, as they are no cells,
but from portions of living matter arranged in clusters, in which
all the plastids remain interconnected. This mode of development
is indicated by the inflammatory changes of the ganglionic ele-
ments, when they return to their embryonal condition.

In the human embryo two months old, the intervertebral
ganglion is composed of medullary tissue, with relatively large
fields of myxomatous basis- substance. The nerves are non-
medullated, which proves that the myeline investment must be
formed at a later period than the axis-cylinder. (See Fig. 180.)

For a successful investigation of the development of nerv-
ous tissue the recognition of two points is, in my opinion, of
fundamental importance — viz. : first, that the nervous sys-
tem is a formation originating in the middle embryonal
layer ; and second, that no isolated " cells" take part in the pro-
duction of nervous tissue. With the knowledge of these facts,
we can understand that in an elongated group of intercon-
nected plastids the central portion may remain unchanged
living matter, the axis-cylinder; while a more peripheral por-
tion may become reticular (horny!) and infiltrated with mye-
line as a kind of basis-substance, and that the most peripheral
portion, by a solidification of the bioplasson liquid, may be trans-
formed into the myeline sheath with a nucleus, in about the same
manner as a fat-globule arises from myxomatous connective
tissue.

Methods for the Preparation of Nerat:-tissue.

Successful examination of the nerve-tissue depends on a suit-
able mode of preservation. Teasing, tearing, pulling, and making
specimens '' half dry " are methods unworthy of being named.

Small pieces of the brain or the spinal cord should be placed

304

XERVE-riSSUE.

in a dark wiue-yellow solution of bioliromate of y>otash, or in
Miiller's fluid. Either of these liquids should be ^eatly in
excess compared with the bulk of the specimens. They will
preserve the nerve-tissue, if changed every fourth or fifth day.
or untn the liquid remains clear. The hardening can be accom-
plished afterward by alcohol or a very weak (one-fifth to one-
tenth per cent.) solution of chromic acid. A slight excess of
chromic acid will soon render the nerve-tissue brittle and not
suitable for sections.

M-

^

Fig. 130. — Intervertebral Ganglion of a Human Embryo,
Eight Weeks Old.

<r, partly solid, partly nucleated, plastids ; N, nerA-c-fibers. not j-et mertuUated : M, delicato
TOyxoniatoiis connective tissue ; B, capillary blood-vessel, cut transversel.v. Ma^rnified 600
<lianieters.

Sections made with razor, or other cutters, are alone appro-
priate, in my opinion, for study of this tissue. The teasing of
the tissue, which is unavoidable even with this mode of prepara-
tion, is the only teasing allowable, and may sometimes show
noteworthy characters. The thinness of the section is its main
value. - By mounting in dilute glycerine the details will be

NKnVF.-TISSrK. 305

hroiijrht to vi(>w in w iiianiui' t':ir sui-i)assiii<>' specimens moniit<'il
ill balsam.

Osniio acid (si'c \n\^J,<' i)) may 1)6 used siieeessfully. The most
important of our ])r<'S('iit n'a<'viits is the oiic-lialf per cent, solu-
tion of iiold, bv nu'aus of which J. Cohnhcim* first succeeded in
clearing np the termination of nerves in the epithelia of the
cornea. From twenty to forty minutes' exposure to this solution
reiulcrs all ))ioplasson fornuitions distinct, altliou^'h the speci-
mens after five or six years become worthless, as they grow too
(hirk for study. Treatment with acetic, lactic, tartaric, and
formic acids assists the action of the gold-salt ; but the proper
use of these acids can be learned only by experience.

Analysis of Bioplasson in its Relations to Nerve-action.

Thoughtful minds for a number of years have anticipated the modern
views concerning the function of the nervous system. I quote from L.
Elsberg (I. c, see page IST)) the following historical data:

''According to Drysdale,t Dr. John Fletcher, of Edinburgh, was the fii'stj
who clearly abandoned the idea that the material elements of an organism
require the addition ' of an immaterial or spiritual essence, svibstance, or
])0\ver, general or local, whose presence is the efficient cause of life,' and who
arrived at the conclusion that ' it is only in virtue of a specially li\'1ng matter,
universally diffused and intimately interwoven with its textm"e, that any
tissue or part possesses vitality.' He denied vitality to any gaseous or purely
liqmd fluid, and any hard or rigid solid ; and thought the only truly li^^ng
matter consisted ' of the gray matter of the ganglionic nerves, which he held
to be universally diffused, and the gray matter of the brain and spinal mar-
row.' He described it as a 'nitrogenous, pulpy, translucent, homogeneous
matter, yielding, after death, fibrin.' ' Chemical analysis, accordingly, must
be considered as useful in showing us, not what such matter was composed of
while it possessed vitality, but what it is composed of afterward.^ ' Not only
is every vital action traced to molecular change, and to consumption and
regeneration of this structureless, semi-fluid matter, combined in a way
entirely sui (jrHcris, but the initiation of these changes is brought by Fletcher
into absolute dependence on stimuli, and all spontaneity or autonomy is
denied to matter in the liv-ing just as in the dead state.'

"A.S Fletcher's work was published in 1835, several years before even
the establishment of the cell-doctrine, we cannot but agi-ee so far with Drys-
dale as to say that Fletcher has framed a ' hypothesis of the anatomical
nature of the living matter which anticipates in a remarkable manner ' its
discovery! In ISJjO, Cohn $ recognized the protoplasm 'as the contractile

* Vircliow's Arcliiv, Bd. 38.

t "The Protoplasmic Tlieory of Life," London, 1874.
t " Rudiments of Plij'siology," Edinburgli, 1835.

i "Nachtrajre zur Naturgeschichte des Protococcus pluvialis." Nova acta Acad. Leop.-
Carol., vol. xxii.. part i., p. 005.

20

306 XEBVE-TISSUE.

element, and as what gives to the zoospore the faculty of altering its tigure
without any eoiTesponding change in volume.' He concludes that protoplasm
' must be regarded as the prime seat of almost all ^atal aeti\aty, but especially
of all the motile phenomena in the interior of the cell.' In 1853, Huxley*
said: 'Vitality — the facility, that is, of exhibiting definite cycles of change in
form and composition — is a property inherent in certain kinds of matter.' In
1855, Ungert thought that ' the proximate cause of the movements of the sap
in the cells is to be sought neither in diosmosis, nor in the action of the
nuclear vesicle, nor in any mechanical contrivance, such as cilia, but it
lies rather in the constitution of the self-moving protoplasm, which, as an
especially nitrogenous body of the nature of that simple contractile animal
substance called sarcode, produces the rhj'thmically advancing contraction
and expansion.'

"In 1856, Lord S. G. Osborne discovered carmine staining, and distin-
guished, by means of coloring it, the li^ang formative matter from the formed
material — a means which has borne important fruits in the discovery of Cohn-
heim's staining of li^'ing matter by gold chloride, and in that of Eeckling-
hausen's staining all except li'V'ing matter by silver nitrate.

"In 1858, and in a number of later articles, t Max Schultze, by showing
that, as had been hypothetically supposed by Unger, the movements of the
pseudopodia and the gi-anules are really produced by active contractile move-
ments of the protoplasm, and by other observations, contributed much to the
establishment of the theory of living matter. Hseckel has also for many
years, and in various publications, 6 labored to maintain and extend the same
theory, of which he thus expresses himself : || ' The protoplasm or sarcode
theory, that is . . . that this albuminous material is the original active sub-
stratum of all vital phenomena, may, perhaps, be considered one of the greatest
achievements of modem biology', and one of the richest in results.' And says
Drysdale : H ' K the grand theorj' of the one true living matter was, as we have
seen, hj^othetically advanced by Fletcher, yet the merit of the discovery of
the actual anatomical representation of it belongs to Beale, in accordance
with the usual and right award of the title of discoverer to him alone who
demonstrates truths by proof and fact. . . . The cardinal point in the theory
of Dr. Beale is not the destruction of the completeness of the cell of Schwann
as the elementary unit, for that was already accomplished by others. . . .
But that, from the earliest -v-isible speck of germ up to the last moment of life,
in every li\'ing thing, plant, animal, and protist, the attribute of life is
restricted to one anatomical element alone, and this homogeneous and struct-

* "Review of the Cell-tUeorj-." British and Foreign Medico-Chirury. Review, October,
1853.

t " Anatoraie uuil Physiologie der Pflanzen," 18.55, pp. 280, 282.

f'Ueber innere Bewegungs-Eisclielnun^en bei Diatonieen," Muller's Archiv, 1858,
p. 330; "Ueber Comuspira," Archiv f. Naturgesch., 1860, p. 287: "Ueber Jln.skelkor-
perchen unU das was man eine Zelle zu uenneu habe," Reichert \iiu\ Dii Bois-Res'inond's
Archiv, 1861, p. 1; "Das Protoplasma der Bhizopoden uud der Ptianzenzellen," Leipzig,
1863.

? " Monographie der Radiolarien," 1862, pp. 89, 116; "Ueber den Sarcodekorper der
Rhizopoden," Zeitscli. f. Wissensch. Zoologie, 1865, p. 342 ; " Generelle Morphologie," vol. i.
pp. 269, 289.

\\ " ilonographie der Moneren," Jenaische Zeitschft. f. Me<licin und Xatiirwissenschaft.
1868, iv. 1 ; translation in Quarterly Journal of Slicroscopical Science, London, 1869. vol. ix.,
p. 223.

1" Loc. cit, p. 42, et seq.

NEU VE- TISSUE. .'307

ureless ; wliilo all the rest of the infinite viirietyof Htnieture and compoKition,
soliil and Huid, wiiich make up iiviii}; l)eing.s, is merely passive and lifeless
formed material. This distinetion into only two r:idieally different kinds of
matter — viz. : the living or germinal matter and the forme<l material — gives
the elue whereby he clears U]) the confusion into which the cell-doctrine had
fallen, and gives the point of departure for the theory of innate indejx'ndent
life of eadi part, which the cell-theory had aimed at but failed to make good.
Tlie one true and only living matter — called by Beale germinal matter, or
biojdasm — is described as " always transparent and colorless, and, as far as
can be ascertained by examination with the highest powers, perfectly struct-
tireless, and it exhibits those same characters at every period of its existence."
. . . The living matter of Beale corresponds to the following histological
elements of other authors : The viscid nitrogenous substance within the pri-
mordial utricle, called by Von Mohl protoplasm ; the primordial utricle itself, in
NaegeU's sense of that term — viz. : the layer of protoplasm next the cell-wall ;
the transparent semi-fluid matter occupjdng the spaces and intervals between
the threads and walls of those spaces formed by the so-called vacuolation of
protoplasmic masses ; the gi'eater part of the sarcode of the monera, rhizo-
poda, and other low organisms ; the white blood-corpuscles, pus-corpuscles,
and other naked wandering masses of li\ing matter ; the so-called nucleus of
the secreting cells, and of the tissues of the higher animals, and many plant-
cells; the nuclei of the cells of the gray matter of the brain, spinal maiTow,
and ganglions, and the nuclei of nerve-fibers. The term of true living or germ-
inal matter can never be given to the following parts, although to some of
them the word protoplasm has been erroneously applied — viz. : the cell-wall
of plants or animals, however delicate or gelatinous ; the threads or filaments
and walls of the vacuoles within protoplasmic masses or cells ; the wall of the
primordial utricle ; the true fibrous, connective, elastic, bony, or other tissues
generally included among the li\dng parts of animals ; even the proper con-
tractile fiber of the muscles, the radiating fibers of the caudate nerve-cells,
and the outer coat of those cells, besides the nerve-fibers in general ; the hard
parts of epithelial cells, and all liquid secretions ; the cilia ; the tissue of
cuticle, hair, nails, horn, and all analogous parts in plants ; the granules in
sarcode ; all coloring matter ; and, lastly, all pabulum, including the fluid
part of blood, lymph, and chyle, and corresponding matters in plants. In
short, the name of bioplasm, given by Beale, or protoplasm (in a restricted
sense, as it will probably be ultimately accepted by biologists), as indicating
the ideal li\dng matter, cannot be given to any substance displaying rigidity
in any degree, fi'om the softest gelatinous membrane up to the hardest teeth-
enamel ; nor to anything exhibiting a trace of structure to the finest micro-
scope ; nor to any liquid ; nor to any substance capable of true solution.
Thus, " nothing that lives is alive in every part," but as long as any individ-
ual part or tissue is properly called living, it is only so in vdrtue of particles of
the above-described protoplasm freely distributed among or interwoven with
the textures so closely that there is scarcely any part one five-hundi-edth of an
inch in size but contains its portion of protoplasm. Thus we see realized the
hj-pothesis of Fletcher — that all living action is performed solely by virtue of
portions of irritable or U\ang matter interwoven with the otherwise dead text-
ures. According to Beale, "of the matter which constitutes the bodies of
men and animals in the fully formed condition, probably more than four-fifths
are in the formed and non-living state. All this was, however, living at an

308 NERVE-TISSUE.

earlier period of existence." This is on an average, for some tissues contain
much less li\ang matter ; the bones, for example, only one-twentieth, and
some textures, when old, not more than one-hundredth.'

"I have made this long quotation from Drysdale's book, because I am
anxious to do full justice to Beale, and I could not find a statement of his
views so succinct for quotation in his own writing. The objection, however,
urged by Bastian to Beale is so very pertinent that it must also find a place
here, but I shall not dwell upon other points on which Beale differs from the
bioplasson doctrine ; such as that living matter exhibits the same characters
at every, period of its existence, and that it is always perfectly structtireless.
' It has always appeared to me,' says Bastian,* ' to be a very fundamental
objection to his theory, that so many of the most charactei'istieally vital
phenomena of the higher animals should take place through the agency of
tissues — muscle and nerve, for instance — by far the greater part of the bulk
of which would, in accordance with Dr. Beale's view, have to be considered
as dead and inert.'"

Meynert's view — that the cortex of the brain is a mirror, on which, by means
of the conducting nerves, impressions from the outer world are projected — has
in late years decidedly gained ground. He found that the nerves of the
special senses go to special convolutions of the cortex of the brain, and that
from other convolutions arise nerves which control muscle action. Hitzig
was the first who discovered points in the cortex of the brain of the cat,
which, upon being stimulated by electricity, produced regularly recurring
motions in the extremities. Later, Terrier and Munk demonstrated in the
brain of apes the isolation of special sensory perception and of muscular move-
ments, usually subject to the will. Their experiments confirm the anatomical
premise of Meynert in its general bearings. It was found that, by cutting
away a certain part of the brain of these animals, blindness would result,
while the removal of another part was followed by deafness, and of still
another by paralysis. If the latter parts, instead of being removed, were
stimulated by electricity, special motions followed, as if they were produced
by the will of the animal. These observers found the keys of the mind of the
animal in the gray substance of the convolutions of the brain, and, by touching
a special key, could simulate the expression of the animal's feelings.

Pathological processes in the brain have gi-eatly aided in coiToborating the
localized nature of sensory and motor functions. Meynert especially pointed
out the center of speech by the study of aphasia, which is a loss of the power to
pronounce certain words. This center is in the Eeil's island, with the claustrimi
outside the third member of the lenticular nucleus. Meynert pointed out, in a
series of careful researches, that the claustrum is a component part of the cortex
of the island, the cortex around the fossa Sylvii, and the posterior orbital con-
volution. It represents the fifth layer of the cortical structure, which is more
than usually developed and serves for a broad connection with other territories
of the cerebral cortex. The connection of the claustrum with an auditory
bimdle renders the walls of the fossa Syhii a field for sound, while the connec-
tion of the claustrum with the fibrous systems of the medulla of the island of
Eeil and the external capsule of the lenticular nucleus renders this field of
sound a central organ of speech. Aphasia depends on a destruction or a

* "The Beginnings of Life: being some account of tlie Nature, Modes of Origin, and
Transformations of Lower Organisms." Loudon, 1872, vol. i., i). 155.

NERVE-TISSUE.

309

morbid change of ganglionic elements in this center. Such facts, compared
with the appearance of muscular movements in the embryo upon the formation

Fig. 131. — Diagram of Nerve Conduction.

ilG, motor ganglionic element; SG, sensitive ganglionic element; G, oflfsliootto the gray
substance of tbe spinal cord; B, ofifslioot to the gray substance of the brain; CO, ofiFshoot
to analogous ganglionic elements for coordinate sensaticm and motion; AC, axis-cylinder,
transformed into MS, a medullated nerve-fiber ; CC, cornea corpascle in connection witli
the sensitive ganglionic element ; M, striped muscle, with MH, the motor hill, in connection
with the motor ganglionic element.

of motor ganglionic elements in. the spinal cord, would also indicate that every
group of muscles has, to a certain extent, independent centers in the gray
substance.

310 NERVE-TISSUE.

The hypothesis becomes, perhaps, admissible that all we call positive
concrete knowledge — f. i., 1, 2, 3, etc., or a, b, c, etc., primarily gained by
sense impressions — is localized in special ganglionic elements, while abstract
or general nervous activity rests in the diffused, nucleated portions of the
gray substance between the ganglionic elements. Such diffused activities
are : hope, fear, imagination, dreaming, etc. The increase of knowledge
throughout life would mean that there was a corresponding new formation of
ganglionic elements. Intelligence could depend chiefly upon the number
of these elements, and their number could be increased by education and by
learning. Memory could be based on the gi'ouping of bioplasson particles,
which at certain times might be brought into motion, and again might retm-n
to relative rest.

Nervous action, perhaps, depends entirely upon a contraction of the bio-
plasson reticulum. Should such a contraction be induced on the periphery
of the body, it would be conveyed to the center, and recognized as pain ; if,
on the contrary, contraction start in the center and be conducted to the
periphery, it would result in muscular movement. From this point of \new
the designation of sensitive and motor nerves becomes superfluous, for
experiments have already proved that the same nerve can at one time be a
sensitive, at another time a motor, conductor. We need only assume sensitive
and motor stations in the centers, in connection with each other. What the
motor agent is which causes movement in the bioplasson reticulum of the
central organ, as well as throughout the whole organism, we do not know,
and consequently are at liberty to give it any name. As regards the spinal
cord, the nerve action seems to be sufficiently plain. (See Fig. 131.)

Eeflex action, coordinate sensation, motion, and conduction from and to
the brain take place in separate routes, which must be in connection with
the sensitive and motor ganglionic elements by means of offshoots. The
multipolar form of these bodies, perhaps, may be accounted for in this way.

X.

EPITHELIAL AND ENDOTHELIAL TISSUE.

THE ideas concerning the character of epithelium and endo-
thelium, as presented here, are widely different from the
opinions usually held upon this subject. The light of the bio-
plasson theory has been brought to bear upon a subject hitherto
but little understood. All the views here advanced have been
taught by me in my laboratory for over seven years, and these
views were in part published in 1878.*

Definition. A single li\T.ng plastid, — for instance, an amoeba,
a colorless blood-corpuscle, or a pus-corpuscle, — with high mag-
nif\4ng powers of the microscope, exhibits a delicate, net-like
stnictui'e, both within the nucleus and in the surrounding body.
The body is inclosed by an extremely thin, shining, homogeneous
layer, and a layer of this kind always lines the vacuoles seen,
temporarily or permanently, in a creeping plastid. The net-work
of the body inosculates with both the peripheral layer and that
inclosing a vacuole. The reticulum of the nucleus, its surround-
ing envelope — the net-work of the plastid, the covering and
lining layers, both of the body and its vacuoles, are formations
of living matter, the active contraction and passive extension of
which cause locomotion and aU changes of form during the life
of the plastid.

In the germinal disk of the more highly developed animals,
which arises from two symmetrical halves of the impregnated

* " Epithelium and its Performances." A paper read before the American
Dermatological Association, at their meeting in Saratoga, August 27, 1878.
Published in abstract. New York MecUcalJournal, 1878.

312 EPITHELIAL AXIJ EXDOTHELIAL TISSUE.

germ, indicative of the symmetrieal halves of the future organ-
ism, three layers are recognized. The so-called mesoblast, the
layer which forms the main bulk of the germinal disk, is covered
on its outer surface by a thin layer of flattened plastids, termed
the epiblast ; the under siu'face of the mesoblast is also covered
by a similar layer, which is termed the hypoblast. In the meso-
blast the iirst -formed vacuole, the future heart, is lined by a thin,
continuous layer, which is connected Avith all sm-rounding plas-
tids by means of delicate filaments. According to our ideas, the
mesoblast must give rise to the principal part of the organism,
composed of connective tissue, of muscles, and of nerves. The
nerve-layer is closely attached to the epiblast, and this is the
reason that, since Remak's time, it has been considered a forma-
tion of the epiblast. Such a conception, however, cannot be
correct, as the nervous system is largely intermixed with con-
nective tissue, carr^-ing blood-vessels, and these latter for-
mations never appear in the derivations of the epiblast and
h\-poblast — /. e., the epithelia. The thin layer around the first-
formed vacuole is the representative of all the future lining
investing layers of closed caAdties, and fiumishes in the devel-
oped organism the tissue termed endothdimn.

All formations in a highly developed animal body which are
analogoiis to the outer or covering layer of a single plastid — that
is, those which cover the external sui'face of the body and line all
the inner cavities in direct or indirect connection with the outer
surface — are termed epithelia. Formations, on the contrary, which
are analogous to the wall of a closed vacuole of a single plastid,
bear the name of endoihelia. Epithelia are found : On the outer sur-
face of the bod I/, the skin and its appendages : the hairs, nails, seba-
ceous, sudoriparous, and mammary glands ; the crystalline lens
of the eye ; in the system known as the gastro-intestinal tract and
its prolongations, the mucous and salivary, pepsine and intestinal
glands, and the liver ; in the ca\Tity of the respiratory tract audits
mucous glands : and in the canities and canals of the fjen ito-urinarij
tract, including all its prolongations into the kidneys and the
genital glands. Endothelia line the closed cavities of the sJiiill and
the spine, all its covering membranes, and all ventricles in the
brain and their prolongation into the spinal cord; the cavities of
the chest, both pleural and pericardial: the caviti/ of the peri-
toneum ; all articulations, and all blood- and hjnqjh-vessels, includ-
ing the cavities of the heart.

This distinction was first estal)lished bv His, who, at the same

Kl'l I UELIAL AM) KSDoTll 1:1.1 A L TISSCK. HVi

time, iiiaintaiiu'd tliat tlic ('))itlu'li!i wvw an <)tf'spriii<:: <tf tlic cjti-
blast aiul the hyi)(»l)last, while tlie eiulotht'lia were fonnatioiis of
the mesoblast, and closely allied to connective tissue. A perfect
distinction between epithelia and endothelia, however, cannot
be carried out for two reasons. First: The history of develoj)-
nient and the scheme of a sinj^le plastid demonstrates that both
e{)ithelia and endothelia are originally flat layers of living matter,
which split up into plastids, the only difference Ijetween them
being that the ej»itlielial layer is on the surface of the Ixxly, while
the endothelial layer lines closed cavities iu the interior of the
body. Secondly : There is a direct communication between epi-
thelia and endothelia at the openings of the uterine tubes into
the peritoneal cavity ; the epithelial formations of the (^varies are
in no communication with the outer world ; the crystalline lens,
which is in its natui-e a formation completely epithelial, is covered
l)y the endothelium of the anterior and posterior chambers of the
eyeball ; the epithelia of the liver join the endothelia of the capil-
laries, and are in direct connection with them. Further, epithe-
lia and endothelia are identical in their intimate structure. Again,
there exist single epithelial layers in the body — f. i., those of the
bile-ducts, the salivary glands, the ui-iniferous tubules; and, on the
other hand, ciliated endothelium is also found in the ventricles of
the brain and the central canal of the spinal cord, etc., etc.

EpithtUa and endothelia represent continuous investing layers
of living matter. The former are the earliest formations in a
developing hodtj, after the stage of indifference introduced by the
segmentation of the impregnated germ is passed. The latter are
formations^ starting with the appearance of vacuoles in the middle
layer of the germ, the future heart and vessels. Both epithelia and
endothelia are devoid of blood-vessels and lymphatics.

Structure. The epithelial and endothelial layers are con-
structed of single polyhedi-al plastids, the formerly so-called
"epithelial and endothelial cells." Each plastid is separated
from its neighbors by a narr(jw cloak of a lifeless, horny cement-
substance, which is closely allied to the basis-substance of the
connective tissue, but is not glue-yielding. Concerning the chem-
ical constitution of these substances nothing is determined. Un-
der the microscope we can see only the lateral portions of the
envelope, which has the appearance of a pale seam around each
polyhedral body. (See Fig. 132.)

The net-work of living matter within the plastids sends delicate
conical offshoots through the cement-substance, both in epithelia and

314

EPITHELIAL AND ENDOTHELIAL TISSUE.

endothelia. These offshoots, up to the present time, were termed
^' thorns of Max Schultze," in honor of their discoverer. This
observer, in 18G4, described thorny or prickh^ cells in the epithelia
of the conjunctiva, the lips, the tongue of children, which, on
being isolated, exhibited rows of prickles, constituting the appear-
ance of "ridged cells." He knew that the prickles were conical
in shape, and in two adjoining epithelia so arranged as to resem-
ble two cog-wheels, the teeth of which are pressed into each
other, but expressed no positive opinion as to their significance.
Later observers, though their number was very great, did not
settle the question of the nature of the prickles. The only fact
admitted by all was that the prickles were very marked in epi-
thelia taken from localities which were subject to an irritation or
inflammation. [In 1873, I declared the prickles to be formations

Fig. 132. — Endothelial Investment of the Peritoneum of a
Chicken, Slightly Stained with Chloride of Gold.

£, polybedial ondotlielia, seiiaratert from oacli otlier by lislit linis of cenient-snbstauce,
interconnected by delicate lilameuts; SS, stoinata in the cement-substance; JiV, capillary
blood-vessel lined by endothelia, seen in edge-view ; BC, blood-corpuscles. Magnilied 600
iliameters.

of living matter, traversing the rims of the cement-substance and
interconnecting like bridges all epithelial and endothelial bodies
(see page 130). That the thorns are of universal occurrence in
the cement-substance and formations of living matter, can be
proved by different chemical re-agents and by the study of
pathological conditions, such as inflammation, fatty degenera-
tion, etc. In inflammation, and in certain tumors, an active new
growth of living matter starts from these filaments, which leads

EPITHELIAL AND ENDOTHELIAL TISSUE. m.')

to the formation of iiiflainiiiatory corpuscles, mihI also of new
epithelia (see papilloma in chapter on tumors).

One of the favorite suhjects for the study of endothelium
was the pcritotwum. The same valuahle reagents which have
l)een of so much service in elucidating the minute structure (jf the
basis-suhstance of connective tissue, have also proved useful for
the revelation of the structure of the cement-substance. These
re-agents are the nitrate of silver and the chloride; of gold. Von
Recklinghausen had demonstrated that the cement-substance,
under the inrtuence of a one per cent, solution of nitrate of silver,
becomes dark l»rown, and that in the endothelia of the lymph-sacs
and that of the peritoneum circular openings appear, which lead
into the lymphatics, and in a very short time admit of the absorp-
tion of fine granules of carmine, aniline, etc., injected into the

Fig. 138. — Endothelial Investment of the Peritoneum of a
Chicken, Stained with Nitrate of Silver.

K, knobs of small endothelia, along the blood-vessels ; T', capillan- blood-vessels, coursing
in C, the connective-tissue layer ot the peritoneum. Maguilied 150 diameters.

cavities. The so-called serous surfaces proved to be closed
lymph-sacs, which are in an open communication with the
Ij'mph-vessels. It became known that the endothelia of the
peritoneum are of varjdng sizes, and E. Klein demonstrated
knob-like protrusions along the blood-vessels, connected with
the growth of the endothelia. (See Fig. 133.)

The two sui'faces of the free peritoneal membranes — f. i., the
omentum, the mesentery — exhibit endothelia differing in size,

316

EPITHELIAL AND ENDOTHELIAL TISSUE.

the endothelia which directly cover the capillary blood-vessels
being decidedly larger than those covering the delicate intersti-
tial fibrous connective tissue. After staining with silver, solid
dark brown, circular spots appear in the bi-own basis-substance,
and are far more numerous in the endothelia between, than in
those above blood-vessels; or there are simple ring-like forma-
tions, or light openings, surrounded by a wi-eath of small endo-
thelia. The openings at the angles of the polyhedral bodies are
termed stomata; those in the middle of a brown line of cement-
substance, stigmata, both being essentially identical — viz.: open-
ings of the lymphatics. Similar formations were found also in the
endothelial layer of capillary
lymph- and blood-vessels, and ^
J. Arnold di'ew attention to j
their largely increased num- ^^'
ber in the blood-vessels of
inflamed tissues, indicating
an active emigration of color-
less blood-corpuscles.

In thin specimens of sil-
ver-stained endothelia the
dark brown cement-sub-
stance is never smooth, but
more or less fluted, and at
regular intervals traversed
by delicate light lines, which
unquestionably correspond
with the "thorns" or fila-
ments not affected by the
silver salt. (See Fig. 134.)

The crystalline lens is
known to be a formation of
the horny germ-layer, the
epiblast; it is, therefore, an
epithelial structure, com-
posed of flat ribbons, which
are arranged in a peculiarly radiating and concentric manner.
The peripheral ribbons are possessed of obhmg nuclei. Delicate
fringes have been noticed along the edges of torn ribbons of the
lens, but their significance was not understood. They are the
same formations as exist in all epithelia — viz., Max Schultze's
" thorns," the connecting filaments of the ribbons. The reticular

Fig

134. — Endothelial Investment
OF THE Peritoneum op a Pup,
Stained with Nitrate op Silver.

A'', nuclei faintly visible in the endothelia; C,
dark brown, interrupted lines of cement-sub-
stance; SO, stomata at the angles; ,S'/, stigmata
in the middle of the brown lines. Magnified 600
diameters.

Kl'ITHKLIM. AM) K\ DOTH ELI \ 1. TISSUE. 'Ml

structure is easily reeoj^nized iu ea(;h ribljon, in }»oth fresh speci-
mens and those preserved in a solution of eldoride of ^old or
chromic acid. Tlie nature of the cement-su})stanee V)etween the
ribbons is made a])parent by treatment with a solution of nitrate
of silver, which coh)rs it dark brown, and at the same time leaves
delicate, lig^ht, conical lines unstained, as is the case in all other
formations of cement-substance. (See Fig. 135.)

The connecting filaments in the cement-substance, owing to
their extreme delicacy, are often imperceptible in fresh prepara-
tions, and even in specimens preserved in chromic acid some-
times only a delicate granulation is visible in their ])lace. To
render these filaments distinct, the staining with a one-half per
cent, solution of chloride of gold must be resorted to. Epithelial
formations are, as a rule, very slowly colored by the gold-salt, as
the ensheathing envelope of the cement-substance seems to inter-

^^.

s—

Fig. 135. — Ribbons op the Crystalline Lens of a Bullock.

F, isol.iteil uuclcated ribbon of reticular structure, and with fringed eilfres ; C, two ribbons
separated by the light cement-substance, interconnected bj' delicate conical lilaments ; 8, two
ribbons, stained with nitrate of silver ; the cement-substance dark brown, iiierced by light
lines. Magnified GOO diameters.

fere with the action of the re-agent on the bioplasson reticulum
in the interior. But the conical filaments in the cement-sub-
stance, if exposed to the re-agent for twenty to forty minutes,
assume a violet color, and are rendered clearly visible.

The cloak of cement-substance is not of uniform hardness ;
it is probably more liquid in some places than in others, as indi-
cated by the observations of J. Arnold, who drove colored injec-
tion liquids into the middle of the cement-substance. According
to Thoma, an indigo-carmine solution being brought in repeated

318

EPITHELIAL AND ENDOTHELIAL TISSUE.

small doses iuto the blood of a living frog will, after a short
time, appear in the cement-substance of columnar and different
stratified epithelia, the latter themselves exhibiting no trace of the
coloring matter. Excavations in the cement-substance seem to
be a necessity for the process of nutrition of the epithelia. In
inflammation the cement-substance becomes liquefied, and there-
upon admits of a free growth of the filaments and a coalescence
of neighboring epithelia into multinuclear bioplasson masses.
In the cement-substance of the epithelia of the liver there are
regular tubular excavations, the bile-capillaries.

Cm-

Fig. 136.— Diagram op the Varieties of Epithelia.

F, flat epithelia in front view ; S, same in siile view ; Cm, cuboidal epitlielia ; Co, columnar
epithelia in side view ; T, columnar epithelia in top view ; Ci, cUiateil columnar epithelia ; B,
bacillated columnar epithelia.

Division. We distinguish mainly three varieties of epithelia —
the flat, the cichoidal, and the columnar or cylindrical, the differ-
ence depending upon the prevailing diameter. (See Fig. 136.)

Flat epithelia exhibit a broad front surface, while in edge
view they are spindle-shaped, because of the gi-adual narrowing
from the middle portion, containing the nucleus, toward the
periphery. The cuboidal epithelia derive their name from having

FA'ITUELIAL AM) KXDOTIIKLIAL TISSUE. iili)

al)out the same diameter in all direetions ; while the columnar
epithelia are elonjjcated in one direction — viz., that verticid to
the sul)jaceut eouueetive tissue. The cement-substance com-
pletely envelops the body of the epithelium.

ColKiitnar tpiflnlid have two sub-varieties — viz., cUiaied cpi-
thelium, with moving, hair-like prolongations on the outer surface,
and haciUated ppifhi'Iiuni, provided \\4th motionless, short, deli-
cate rods, such as are found in the intestinal canal and the bile-
ducts,

Columnai*, ciliated epithelia usuidly occm- in single layers ;
sometimes, however, the plastids inserted between the feet of the
eolumiuir ejiithelia are so numerous, and the wedged formations
so regularly arranged, as to give the appearance of stratified
columnar, ciliated epithelium — f . i., in the larynx, the trachea,
the larger bronchi, the mucosa of the nasal cavities. The basis
of the epithelial l)ody — /. e., the broadest outer surface — is sup-
plied with delicate bent hair-like formations, which, during life,
and for a short time after the removal of the epithelia from the
body, have a waAdng motion, in a direction corresponding to the
concave side of the hairs. Max Schultze has observed that the
cilia penetrate the investing shell of the cement-substance, and
are visible in the interior of the epithelium. Th. Eimer and E.
Klein have demonstrated that the cilia, penetrating the outer
sheU, are in connection with the net-work within the epithelium.
This fact I can fully corroborate. It explains the motion of the
cilia in a satisfactory manner. The reticulum during life is
never in perfect rest, and as each hair is attached to the reticu-
lum by its short arm, while the long arm projects freely, the
horny cement-substance representing the fulcrum of the lever,
a slight pull on the short arm must result in a marked extension
of the free long arm. This excursion will be most e\adent in the
direction of the conca\'ity of the cilium, each one being slightl}^
curved. It also becomes explicable why liquids, slightly stimu-
lating the li%dng matter, increase the motion of the hairs, and
make them move actively, even after they have become appar-
ently inert. This delicate motion in one main direction is of
importance in carrsdng foreign bodies or secretions outward, and
other substances inward. The motion in the aii- passages — f. i.,
tending upward — will greatly assist in the elimination of mucus,
which, collecting on the most sensitive portions of the larjTix,
the inner surface of the posterior wall, and the under surface of
the vocal bands, produces reflex action, such as hawking, cough-

320

EPITHELIAL AND ENDOTHELIAL TISSUE.

ing, etc. The motion of the cilia, in the cavity of the litems
tending toward the mouths of the tubes, will assist the sperma-
tozoids in reaching the ovum ; while the motion in the Fallopian
tubes, leading downward, will carry the ovum into the cavity of
the uterus.

In man, ciliated epithelia are fcmnd in only a few localities.
They exist in the respiratory portions of the nasal cavity; in
the Eustachian tubes ; in the

V

■■■■' wm^^-?mm

labyrinth (hair-cells) ; in the
larynx, beginning from the
under surface of the epiglot-
tis, with the exception of the ^
vocal bands ; in the trachea,
the bronchi, and bronchioli ;
also in the ejaculatory ducts
and the vas deferens of the ^
male, and in the uterus and
the Fallopian tubes of the
female. (See Fig. 137.)

In lower animals, the cil-p
iated epithelia and endothelia
are far more abundant; in
the frog, for example, they
are present in the cavity of
the throat, the pericardiac
sac, etc. An easily accessible
place for obtaining ciliated
epithelia, exhibiting acute
movements, is the seam of
the mantle of the oyster.
Open the valves, cut off a
small portion from the most
pigmented seam, transfer it
to the slide with a small drop

of the juice of the oyster, and cover with a very thin covering-
glass.

The feet of the columnar epithelia— that is, the extremities
opposite the basis, and serving for attachment to the subjacent
connective tissue — are sometimes blunt, sometimes very thin and
curved, with bifurcations or indentations. The latter feature,
especially in the juvenile condition of the epithelia, is due to
the presence of relatively small, many-shaped plastids, which

Fig. 1137.— Ciliated Columnar Epithe-
lia, FROM THE Nasal Cavity op

Man.

E, row of columnar epithelia; i'', detached
epithelia; P', iriegulaily shaped plastids wedged
in between the feet of the epithelia ; C, connective
tissue, hounded toward tlie epithelia by a light
seam ; iS', the basement membrane. Above this a
flat layer of endothelia is visible. Magnified 500
diameters.

KPITIIF.I.IAL AM) F.XlXnil I'.I.I M. JlSSlh: .'L'l

ai)|)<'ar jmrtly lumioficiUMHis or partly iiiiclcalcd, with otfsliools.
Tliesc iiidid'crcnt corimsclcs ai'c evidently the stai'tinj^ inatei-iid
for newly j^i-owiiiu' epitlielia. The connection of these wedf^ed
j)lastids /;/ .s/7// is aei'oiMi)lishe(l by delicate filaments, which ti-a\'
erse the surroundinji' I'inis. The tilainents themselves often
increase in hulk and f^ive rise to new^ epithclia.

Ciliated endotlielia are met with in the investment of the
ventricles of the l)i"ain and their continuation, the central canal
of the spinal cord, /. c, the so-called ependyma of Purkinje ; and
also on the surface of the plexus choroidei of the pia mater. In
children their presence is invariable, l)ut in adults they are not
found in every case. In the central canal of the spinal cord the

.^-_^^.

-^::

^■,\-^

w^^^^^^^M^^m^m^^^^^^'^'^^^^^^^

Fig. 1:!S. — Central Canal op the Spinal Cord op a Child,
Transverse Section.

K, wreiitli of ciliated cndotheliii, in coiinoction with tlie subjacent connective-tissue ; iV,
norve-libiM-8 of tlie anteiior commissui'e ; ir, wliite substance ; F, floor of the anterior longi-
tudinal lissure, covered with flat endotlielia. Magnified SOO diameters.

ciliated endotlielia have a radiating- arrangement, and in the
posterior wall of the canal exhibit a gradual decrease in size
toward the median line, where a slight fissure is observed. Here
the cement-sul)stance between the endotlielia and also their
nuclei are, as a nile, but slig'htly marked, while the cement-layer
at the base of the endothelial wreath is quite broad. (See Fig.
138.)

Single epithelial hn/ers may exhibit any of the a bo re-u anted forms
Cflat, cuboidal, columnar) ; in the uriniferous tubules, for instance,
21

322 EPITHELIAL AND ENDOTHELIAL TISSUE.

we find all varieties, according to the calil)ers of the tubules.
Stratijied cpit/wlidl lai/ers are composed of all tlie three forms.
Such stratified epithelia are found : on the surface of the skin,
the oral cavity, the throat, the oesophagus, and the lowest portion
of the rectum ; also, in the lowest portion of the nasal cavities, on
the upper siu'face of the epiglottis, on the vocal bands ; further
in the vagina, the cervical portion of the uterus, the urethra, the
bladder, the ureters, pelves, and calices of the kidneys ; lastly, on
the conjunctiva, the outer surface of the cornea, the lachrymal
ducts, the external auditory canal, the outer surface of the tym-
panum, and the Eustachian tubes, at their mouths in the cavity
of the throat. Wherever stratified epithelial formations occur,
the flat variety invariably composes the outei' laj^^rs ; the cuboidal,
the middle layers, and the columnar the lowest layer, nearest to
the connective tissue. In places where two stratified epithelial
layers come in contact, there is often found between them an
apparently structureless layer, the horuy or cuticular layer, so-
called in contradistinction to the basement layers, which exist
between epithelia and connective tissue. (Cuticular formations
are seen in many places between the layers of flat and cuboidal
epithelia in the skin ; quite regularly between the inner root-sheath
and the hair, and between the inner and outer root-sheaths of the
hair. The cement-substance in stratified epithelium is always
marked and traversed by delicate filaments, especially plain in
places which are the seats of slight irritation. (See Fig. 139.)

The nuclei of the epithelia, particularly of the cuboidal, in thin
sections are liable to drop out, leaving a vacuole. In the flat
epithelia the niiclei and the bod}^ of the plastid are finely granu-
lar— viz. : the living matter has decreased, and the horny sub-
stance— a derivation from the bioplasson licjuid — increased in
amount. The nucleus, or the nucleolus, even in flat epithelia
— f. i., of the oral cavity — may exhibit, under certain circum-
stances, the characteristics of living matter (Strieker). The flat
epithelia of the most external part of the skin and those of the
nails and hairs become deprived of nuclei and of life, and are
transformed into a diy, horny material.

R. Heidenhain has drawn attention to the presence, in the
interior of epithelia, especially kidney epithelia, of delicate, rod-
like formations. Their significance will be spoken of in the
chapter on the kidneys.

The attachment of epithelia and endothelia to the connective
tissue is either direct, by means of delicate filaments penetrating

F.PITUFJ.IAl. AM) r.XnOTHKI.IM. TISSUE.

32:5

the rim Ut'twi't'ii tlu' tVct of tlit' cpitliclia and the lU'i^hltoriiij;
tilHTs of c'oniK'ctive tissue; or it is iiidirt'i-t, l)y means of an intei--
veniu^ basement layer. The latter is probably pervaded by a
bioplasson n'tieuliim (T liavc seen it in Bowman's layer of the
eornea of the eat), wliich inosculates with that of the e])ithelia.
Basemeut layers, however, are not eonstant formations; they are
sometimes ])road, sometimes narrow, and sometimes altofrether
absent, in one and the sanu- or^an in different persons. The
outer surfaee of the basement membrane, in many instances, is
found to be covered by a layer of flat, polyhedral bodies discov-
ered by V. Czerny, by means of silver-staining. These bodies are
classed amonti' endothelia.

Fig. 139. — Stratified Epithelium of the Skin, Covering a Myxo-
fibroma ON THE Right Shoulder. Vertical Section.

F, flat epitlielia : Cm, cuboidal epitlielia; Co, columnar epitlielia, all the three c<>ini»osiiig
the epithelial layer. E ; V, derma of skin, composed of vascularized connective tissue, C.
Mairuitied GOO diameters.

Termination of Xcrrcs. Since Cohuheim's researches, we know that the
finest axis-fibrillfe of the ners-es terminate in the epithelial layers. The ter-
mination was described by some obsersers as a plexus between the epithelia.
while others (Pfliiger. Flemming:) claim that the axis-fibrilte penetrate the
body of the epithelium, and may terminate in its nucleolus. My own obser-
vations enable me to state that the axis-fibrillae — which, in specimens stained

324 EPITHELIAL AND ENDOTHELIAL TISSUE.

with chloride of gold, can be recognized hy their beaded appearance and their
dark violet color — run in the cement-sulistance betAveen the epithelia, and in
this sitnation are in direct union with the filaments ("thorns") interconnect-
ing the bioplasson reticulum of neighboring epithelia. (See Fig. 140,) In

Fig. 140. — Diagram of Termination of Nerves in Epithelial Layers.

AO, axis-cylinder, dividing into axis-flbrilla', AF, wliicli penetrate tlie liyaline or Ijase-
ment membrane, M, and course in the cement-substance between the columnar epithelia,
CO, and the cuboidal epithelia, CU. The axis-tibrilhe are directly connected with tlie trans-
verse filaments in the cement-substance, and indirectly with the bioplasson reticulum of llie
epithelia.

this way, the active portion of the epithelia — the living matter — is controlled
by the nerves. Here and there a beaded thi-ead can be traced into the body
of an epithelium, and this occurrence is easily understood if we bear in mind
that the nerve-fibrillfe and the reticulum of living matter are, in essential
points, identical formations. The only reliable means for tracing the nerve
terminations is by chloride of gold staining. It is absolutely necessary, how-
ever, first to find the connection of the axis-fibrillte with larger meduUated
or non-medullated nerves before we can positively determine their nervous
natiu'e.

Recently, a number of formations in the organs of sense have been termed
Neuro-epithelta (Schwalbe). This refers to formations which are either epi-
thelia or take a genetic origin from epithelia, and represent the terminations
of the sensual nerves. In this group are included the rods and cones in the
retina of the eye, which are composed of a number of transverse disks ; the
outer portions of the rods during life show a bright red color, which, by its
discoverer, Boll, was termed the "Aasual purple." The rod- and cone-fibers,
with their nucleated nodules, constitute the external granular layer of the
retina. In the labyrinth, or the internal ear, especially in the maculae and

J'.fl I'llF.I.IM. AM) I'.XItoril 1:1.1 M. J/SSCh'. :}2r)

cristii' iicoiistii'ii', iirc I'oiiml tlic ciliati-tl iiiiditory, ami Wet ween tliosc tlio iioii-
I'iliatt'il, so-callfd iinlilTcn'iit rpitlii'liii. In ('(irti's orf^aii within th(! ('ocliloa
tluTc exist tlie so-called hair-epithelia, wliieli are diviil(Ml into tlie iiiiiiM' and
outer, the latter bein<^ arranj^ed in four eontinuons rows alonf^ tlie exterrnil
pillars. In the f^ustatory buds (Sehwalbe, 1jOv6u) there are filiform bodies
surrounded by eoveriiiK epithelia; they are found on the epithelial invest-
ment of the circumvallate papilhe, on the epitlielia of the hard and soft pal-
ate, and of tlie posterior surface of the epiglottis. In the olfactory region of
the mucosa of the nasal cavity, Max Sclmltze discovered, in addition to large,
eolumiKir, non-ciliated epithelia, interposed delicate nucleated filaments,
which, ill amphibia and Itirds, but not in man, have delicate cilia at their
external ends. In none of the formations of neuro-o])ithf'lium is the ter-
mination of the nerve-fil>rilla3 clearly elucidated.

I'h/iiioitcd Ej>itli(lift and E/idotlirlia in man are of infrequent occurrence,
while in the lower animals they are exceedingly abundant. The i)igmented
epithelial layer of the human retina is composed of very regular, hexagonal,
flat bodies, the central nucleus, as well as the cement-substance, always being
without pigment. The amount of the pigment, and also its shade, varies
gi'eatly according to the general complexion of the individual. The more
blonde this is, the less pigment will be foimd in the epithelia, and in albmotic
persons it is entii-ely absent. From the inner surface of the epithelial bodies
numerous filaments arise, passing between the rods. These filaments are
slightly pigmented in man, but in birds, fishes, and amphibia they abound in
coloring matter.

Glands. All the organs of the body properly termed glands
are formatiou.s of the epithelium. Some authors have given
these epithelia the unnecessary name of '' parenchyma or
enchyma cells." The large majority of glands are composed of
a single layer of epithelia. In the body of the gland the
cuboidal variety is usually found, and in the duct the columnar ;
the cuboidal, however, are sometimes so much elongated as to
represent the short columnar variety. Several layers of cuboidal
epithelia are seen in the sebaceous glands and the prostate of
the adult.

We distinguish two varieties of glands — viz., the acinous and
the tubular. (See Fig. 141.)

A roundish, pouch-like prolongation of the epithelial layer
into the connective tissue forms a simple acinous gland. Exam-
ples of this variety are the mucous glands of the oral cavity, the
larynx, the trachea, and some of the sebaceous glands. Repeated
foldings of the pouch constitute the formations called compound
acinous or racemose glands, such as the sebaceous, the lachrymal,
the salivary, the lacteal, the prostatic, and other mucous glands
— f. i., those in the mucosa of the tongue, of the duodenum, of
the trachea, and the glands of Cowper and Bartholin!. A third

326

EPITHELIAL AND ENDOTHELIAL TISSUE.

variety is the currant-shaped racemose gland, in which the acini
encircle the h)n<iitii(liiial duct, as in the Mej'honiian o-hmds.

A prokjngation of the ei)itheliuni in tlie longitndinal, or rather
^ p in a vertical, direction is

termed a simple tubular
(jhind, snch as the pepsine,
the intestinal, and the ntric-
nlar glands. Repeated ram-
ifications of the tubules re-
sult in the formation of
compound tubular glands ;
for example, the urinifer-
ous and seminiferous tub-
ules. Another sub-variety
of tul)ular glands may orig-
inate by the coiling of the
tubule. Examples of these
coiled tubular glands are
the sweat and ceruminal
glands.

There are transitions
between these two princi-
pal varieties, when the acini
are slightly elongated, as
in the prostate, in the mu-
cous, or Littre's glands of
the urethra, and the mu-
cous or Brunner's glands
of the duodenum.

According to this defi-
nition, only epithelial —
/. e., secreting formations
— can properly be desig-
nated glands, and all the
so-called lymph-glands, the
adenoid lymph-ganglia, the
spleen, the thymus, and the thyroid body should lie excluded
from the glandular system, as they are not secreting, neither
are they epithelial in structure.

The epithelia rest upon a delicate hyaline layer of connective
tissue, which bears the superfluous name of a " membrana pro-
pria." It is of varying width, and is identical with the " base-

FiG. 141. — Diagram

Glands.

The series A exhibits tlie varieties of acinous
glands: a, the simple poucli; h, the braiichiug race-
mose form ; c, the brandling eurrant form.

Tlie series T exhibits the vaiieties of tubular
glands ; a, the simple tube ; b, the compound brandl-
ing tube; c, the coiled tube.

/.'I'll n /.If. \ I. .\M) i:mk)Tiii:i.ial rissrE. :{27

ment ineinljranr" of liowiiiiin. Hetwct-n the ejuthelia and tlic
liyaliiu' layer a Hat, delicate endothelial foi-niatioii is often found,
which is well marked in the seniinifei-ous tul)tdes (.Mihalkovits)
and in the nriniferons tubules (C. Ludwij;). The hyaline layer of
the salivary •glands exhiliits, accordinj^ to Boll, delicate radiating
spokes, enianatin«!: from the flat, central nucleus, which may be
considered either stellate connective-tissue corpuscles, or i"ib-like
led«i:es of the apparently structureless membrane. Outside of
this layer is a delicate interstitial structure of fibrous connective
tissue, freely su]»])lied with blood-vessels and nerves. Connective
tissue enveloj)s the larger glaiuls, forming a dense, firm capsule,
called the tunica albuginea.

The nerves of the interstitial connective tissue are of both the
medullated and non-medullated varieties, and not infrequently
small ganglionic elements are met with along their course. The
idtimate terminations of nerves are not yet fully understood ;
but, as far as my own observations go, I feel inclined to regard
the termination rei)resented in Fig. 140 as the most common.

Very little is known about the lymphatics of the glands. The
so-called lymph-spaces, produced by parench\Tnatous injection,
are unquestionably artificial formations, and are not entitled to
the name of lymphatics. A complete sj'stem of Ijinph-vessels
is known to exist in only the testes.

Perfornifuices of EpitheUum. The principal function of epi-
thelium, besides the protection of the body, the transmission of
terminal nerve-fibers — therefore of sensation, etc., is the elimina-
tion of effete material from the body, viz. : by secretion and excre-
tion. The horny, epidermal layer of the skin, on account of its
indifference, \\-ithin certain limits of course, to the action of acids
and alkalies, and on account of its being a bad conductor of heat,
serves for a protection to the body and all cavities exposed to the
outer world. The chief office performed hi/ epithelia is unquestion-
(ihlji that of secretion, which is carried on exclusively by epithelia,
arranged as glands. Every glandular formation is epithelial, and
each epithelial body may be looked upon as a gland, inasmuch as
all secretory action is based upon the function of each single
epithelium. All those processes which are considered the most
disgusting in the animal economy are performed by epithelia ;
but it is epithelium, also, which produces the sweet, nourishing
liquid called milk, and all its derivations, and which gives rise to
the most essential material of generation — vi^. : thespermatozoids
and the ova.

328

EPITHELIAL AND ENDOTHELIAL TISSUE.

Aside from some special secretions, there are three I'arieties —
viz. : the icdtcri/, the mucon.s, and the /((tti/. (See Fii>^. 142.)

faj The lentcrij secretion cannot be directly studied under the
microscope. We may infer, by watching amoebae laden with car-
mine particles, that, at the time when, through the visible con-
traction of the living matter within the body, carmine particles
are thrown out from the interior of the ama'ba, a certain amount
of its fluid is discharged with them. We come to this c(mclusion
from the fact that the carmine granules are extruded with a
certain force, in a stream of liquid. We must also conclude that
the opening in the wall of the amoeba kindly and immediately
closes, for the amoeba displays the same amount of activity after

Fig. 142. — Diagram of the Process of Secretion.

The series TT illustrates the watery secretion: a, a i)!asti(I, with foreign .ijvaiiules iu the
meshesof the reticulum ; b, escape of some grauules, with some hioplassoii liquid.

The series 31 illustrates the mucous secretion : a, mucous globule formed at the top of the
epithelium ; h, a mucous globule discharged ; c, a mucous corpuscle discharged ; iu both latter
cases a goblet left.

The series -F illustrates the/atti/ seccetion; a, first-formed fat-granules; ft, coalescence of
fat-granules into a fat-globule.

as before this process. A liquid present in the blood, which is
to be excreted, must necessarily pass through the walls of the
blood-vessels and first enter the epithelia before it can be expelled
from them. The discharge of a certain amount of liquid

i:riTiii:i.iM. .i.\7> kxdoi iiki.ial t/ssi'k. 32!)

is evidently due to the eoiit raet ion of the li\in<i- net-work of
the epithelium, on the one hand, and a rupture in the wall of
the epithelium, on tlie othei-. This a])ertui-e ))rol>al>ly closes
innnediatoly upon cessation of the conti-aclion and i-ei'slaiilisii-
meiit of i-elativc i-est in the reticulum. Wateiy seei"eti(»n is
accomplished l)y the hichrymal aiul the sweat ji'hiiids. The latter
proiUu-e a fluid, varying greatly in the amount of its solid constit-
uents and its consistency at diiferent times, which indicates that
tlie livini; nuitter of the epithelium itself has an influence on the
chemical miture of the secretion. At the apjn'oacli of death, the
pi'rspiration is inspissated and almost mucous in character. The
main function of the uriniferous tubules is the inspissation of
the fluid pressed out from the l)lood- vessels of the tufts of the
kidneys.

fhj The itiucoufi secretion can be directly observed under the
microscope l)est on a minute particle, cut from the inner surface
of the small intestine of a fi"og-, with the addition of a very dilute
solution of chromic acid or l)ichromate of potash ; pure water
acts with too much rapidity. We first observe a swelling of the
body near the outer or free surface of the columnar epithelium.
Tliis can be accounted for by assuming that the e})itheliuni
imbibes the liquid which causes the swelling of the meshes
of the bioplassou reticulum, and at the same time produces
a considerable stretching of the reticulum. A contraction
of the posterior portion of the bioplasson reticulum results,
and this also assists in the enlargement of the anterior por-
tion. The covering cement-substance of the free surface pro-
trudes, and its delicate rods fall off. The cement-sulxstance, after
having reached its utmost capacity of expansion, bursts, and a
pale, globular body is thrown out — i. e.^ the swelled portion of
the epithelium, in which no trace of the former structure can be
seen. We must admit, however, the presence of a stretched
reticidum in the mucous globule, too, and also an extremely thin,
expanded, investing layer of the bioplasson. A number of the
above descril>ed pale mucous globules coalesce and form the jelly-
like mass called mucus.

When the process of swelling goes on more slowly, the whole
bioplasson enlarges within its envelope of cement-substance, and
after being freed, the nucleated plastid, now termed '' mucous
corpuscle,'' still exhibits the net-like structure ; or we may see
isolated, torn granules in an active, so-called " molecular " mo-
tion, the broken particles of the former bioplasson reticulum.

330

EPITHELIAL A XI) KXUOTHELLl L TISSUE.

Salivary and nuioons coi-puscles arise by this same slow action
from the contents of the epithelia. The investment of the
cement-snl»8tance, being partly or totally emptied and perforated
at one end, gives the appearance of a ''goblet-cell." Formations
termed goblet-cells are met with, in nnmbers greatly var^-iug
on all mucous surfaces : they are very numerous in the small
intestine of rabbits suffering fi*om diarrhoea, and also in the
mucosa of the artificially inflamed stomach of animals (Strieker
and Kocslakoflf).

A similar process of the formation of mucus is often observ'ed
in the mucous ghmds of the fi-og s skin ; liere the production of

St:-"" ^^'

Fig. \\?>. — Mucous Glaxds from the Skin of a Frog.

C, connective-tissue frame, caiTj-ing nieilullated nerve-fibers, ^^ coursing between tlie
glands, .V, and sending deUcate raniules to tlie cement substance of the epitheUa ; K, elon-
gated cuboidal epitlielia, paitly transformed into M, the mucous frlobules ; L, the central
caliber. Magnified 400 dlanieters.

mucus from the epithelia of the gland is diagram matically plain.
(See Fig. 148.)

A variety of mucous secretion is that of the stomachic juicf,
of the bile, and the semen. The acidity of the stomachic juice
is unquestionably due to a peculiar chemical action of the living
matter of the epithelia, for the l)lood is always alkaline. The
bile is a product of the liver-epithelia, each of which is a labor-

KI'ITIIhl.IAl. AM) F.SDoril 1:1.1 M. TISSUK. '.\'M

sitofv. iiiaiiut'act iiriiiii' clit'iiiical jtruducts troiii the pliisiiia of tlu^
l)l(»t»(l, and i»r()l)al)ly also tVom the ircl l)loo(l-corj)iisclt'S, Tlic col-
oring matter of the bile is known to be closely allied to lui'nio-
globiue. In the fluid of the semen formations of living matter
aresiis])ended — the spermatozoids, which are direct offsprin<;s of
the e})ithelia of the testicles. Saliva represents an intermediate
condition between the watery and mucous secretions.

R. Heidenhain first drew attention to the differences in tlu^
aspect of the epithelia of the salivary glands, under the different
conditions of fullness and contraction. He found the ej)ithelia
in starved dogs light colored, ver}' much swelled, pai-tly destitute
of granules, and unaffected by the carmine stain, although the
nucleus would be deeply colored. In epithelia of dogs, whicli
before death were al)undantly fed, or whose salivary glands, by
means of electricity, were stimulated to an intense and long-
continued secretion, the epithelia were, on the contrary, small,
regular in outline, and their nuclei less stained with carmine.
In the first case, the central calil^er was imperceptible ; in the
latter, it was very distinct. The same observer discovered in the
epithelia of the pancreas, also, pecidiarities depending upon the
state of the secretion. He called the upper portion of the epi-
thelium granular, the lower light portion structureless ; and in
the process of secretion the upper layer predominated largely.
Heidenhain and RoUett discovered varieties of epithelia in the
pepsine glands, which were unlike in appearance, some being
very large and swelled, with a distinct niicleus; others small,
about the size of the ordinary cuboidal epithelia, and not dis-
tinctly nucleated. These facts, inexplicable to their discoverers
and more recent investigators, are fiilly understood by recog-
nizing the presence of the bioplasson reticulum of the epithelial
bodies within the investing layer of cement-substance. When
the epithelia of the salivary, the pancreatic, and the stomachic
glands are laden with secretion, the meshes of the reticulum
are enlarged, and the reticulum itself stretched ; but when the
ejnthelia are emptied of their secretion, the reticidum is in a con-
dition of equilibrium. Bioplasson is accumulated in larger
quantity at the portion of the epithelia, nearest to the connective
tissue, exhibiting at all times a nearly homogeneous, shining
appearance.

Unquestionably, in the process of mucous secretion a portion,
or it may be the whole, of the bioplasson of individual epi-
thelia is destroved. With this fact before us we can readilv

332 EPITHELIAL AND ENDOTHELIAL TISSUE.

understand the weakening of the whole organism by diarrhoea,
the relief afforded by drastics in certain diseases, etc,

((•) TJie fdttij secretioti can be best studied under the micro-
scope in colostrum corpuscles, which are suspended in the serous
discharge of the mammary glands for a few days after delivery.
Here we see the first-formed fat-granules still in connection with
the net-work of the li\dng matter within the plastid, and we
arrive at the conclusion that fat is a directly transformed living
matter (see page 28). During the active locomotion of a colos-
trum corpuscle, very often fat-gi'anules are thrown up from its
interioi- (S. Strieker). After a few days, however, no more
colostrum corpuscles are secreted, because the living matter of
the epithelia is nearly completely transformed into fat-gi'anules,
leading to a continuous destruction of the epithelia, the gi-anules of
which commingle with a serous fluid and form the emulsion called
min-. This process of fatty change in the living matter of the
epithelia of the mammary glands is a remarkably rapid one. In
microscopic specimens of a breast from the corpse of a nursing
woman, we find in the secretary epithelia little unchanged bio-
plasson, the greater part of it being transformed into fat-
granules. If these be extracted from the specimen with oU of
cloves, only the shells of the cement-substance of many of the
epithelia are left behind. Through what agencies the enormously
augmented bioplasson becomes transformed into fat is at pres-
ent not understood. There is no doubt, however, that this
material is an offspring of the epithelia. Those who claim that
the new material tor the formation of milk are '' leukocytes,"
or emigrated colorless blood-corpuscles, are in the dark regard-
ing the nature and the function of epithelia and glands. The
serous liquid in which the small fat-granules of the milk are
suspended evidently comes from the blood-vessels ; for it is well
known that abimdant di-inking increases the quantity of milk.
The amount of milk furnished by one udder, in the act of milk-
ing, greatly exceeds the volume of the udder, which indicates
that a continuous flow of the plasma of blood takes place dui*ing
the milking process. Toward the end of milking, the plasma
being exhausted, very rich, inspissated mUk is obtained.

The highest degree of fatty change of the bioplasson is
reached in the sebaceous and the ceruminal glands. The won-
derful apparatus for the extrusion of the fat from the sebaceous
glands will be spoken of in the chapter on the skin.

I'-.i'iTii 1:1.1 M. .\.\n i:.\n(rnfi:fj.\f. 'nssrE. ?,'.v.\

Tin; Vascular Systkm.

The vascular system is foniicd tVoin the middle oci-mimd
layer, — the im'S(>l)last. — and es])t'eially of the coiiiu'ctive tissue,
•which alone cari'ics lilood- vessels. The different portions of this
system are the heart, the arteries, the capillaries, and the veins.
In the heart the muscular apparatus is highly developed, as this
is the principal motor for the hlood current. Arteries always have
a muscle coat, which is comparatively more developed the sjnaller
the caliber of the vessel, evidently to admit of an independent
activity in the motion and distribution of the blood. The veins
have a thinner coat of muscular tissue than the arteries, while
the capillaries have no muscnlar investment whatever. The
layer constantly present in the heart, as well as in all blood-
vessels, is the most internal — viz.: the endothelial. This, as
previously mentioned, is the representative of the investment of
living matter of the vacuoles, which are visible at times in single
plastids. The endothelial layer, in the earliest stages of forma-
tion of blood-vessels, is a continuous investment around the
vacuoles, and in a later stage of development divides to form
single plastids, which, lalthough separated from each other by a
narrow rim of cement-substance, still remain interconnected
throughout life by means of delicate filaments (''thorns"). The
cement-substance, under certain conditions, becomes permeable
to both colored and colorless blood-corpuscles. The nourishing
material — the plasma of the blood — must necessarily penetrate
the endothelial layer before it can reach the neighboring tissue,
and the number of blood-vessels is always proportionate to the
acti^^lty of the tissue in which they lie. Muscles — f. i., glands,
the gray suljstance of the nerve-centers — are abundantly sup-
plied with blood-vessels ; while the comparatively inert cartilage,
on the contrary, has a very limited supply. Blood-vessels are
found in the greatest numbers in the organs in which the oxyda-
tion of the blood is accomplished — /. ^., the lungs. Wliat influ-
ence the bioplasson of the endothelia has upon the exchange of
liquids and gases we are unable to say; this much is certain,
however, that all endothelia are bioplasson formations, manifest-
ing vitality in a high degree, and not " elastic plates," as some
histologists claim. The striking changes that occur in endo-
thelia during inflammation are a direct proof of their life and
activity.

(1) The Heart. The muscle of the heart is composed of branch-

334 EPITHELIAL AND EXDOTHELIAL TISSUE.

m^ and anastomosing striped fibers, "vs^th verj' small sarcous
elements (see page 272, Fig. 116). The fibers are an-anged in
bundles and surrounded by a connective-tissue envelope, — the
external perimysium, — which sends prolongaticms between each
single muscle-fiber and its neighbors ; this last formation consti-
tutes the internal perimysium. The points of attachment for the
muscular fibers of the heart are the fibrous rings at the auricido-
veutricular (>pening^ and the tendons of the papillary muscles.
The perimysium is abundantly supplied with blood-vessels and
hnnphatics. H^Ttl discovered that the heart of many low verte-
brates— f. i., the frog — is destitute of blood-vessels, and that sin-
uous prolongations from the ca\'ities of the heart take their place.
The endocardium and the pericardium have a capillary system
with wide meshes. In reptiles and most of the fishes, accord-
ing to the same observer, the muscle of the heart is composed of
two distinctly separated layers — abroad inner, which is without
blood-vessels, and a narrow outer, layer, which has a well-devel-
oped capillaiy system.

The endocardium is composed of a layer of fibrous connective
tissue, var^-ing in Tsidth in different portions and largely inter-
mixed with elastic substance. The inner surface of this structure
is covered by a delicate layer of large and flat endothelia, which
is attached to a homogeneous, so-called hyaline membrane. The
dense, fibrous connective-tissue partitions termed the valves,
originating from the rings of the ostia, are also covered with
endothelia. According to Gussenbauer, there are found in the
peripheral portions (^f the valves, on the surfaces looking toward
the auricles, numerous circular and radiating muscle-bundles,
which come from the muscles of the septum of the aiuicles. The
muscle layer of the auricles, however, is much less developed
than that of the ventricles, wliile the elastic layer beneath the
eudotheUa is veiy marked. In many places, the structure of the
wall of the auricles is similar to that of the large arteries. Pur-
kinje's filaments in the endocardium of cattle and other animals
are considered as peculiar forms ot development of striated mus-
cle-fibers.

The pericardium is a connective-tissue formation, composed of
coarse interlacing bundles in the parietal, and of delicate inter-
lacing bundles in the visceral, portion. The free sm-face of both
portions is covered with flat endothelia. The plexuses of blood-
vessels and the lymphatics are broader in the pericEirdium and
endocardium than in the muscle of the heart. According to

F.l'l IIIF.I.IM. AM) i:SI)()Tlli:i.lM. TISSfF..

•.v.\:>

,1/— -z.^

\Ve<ll, tlic lynii)liatics arc very nuineroiis in the fat-tissue lyiii^
lu'iu'ath the visceral layer of the pericardium.

The nerves of the heart are of both the Tuedullated and non-
nicdullatcd varieties. Tlie

former are l)ranches<)f the
vapus nerve, the latter of
the sym])atlictic system ;
the plexus cardiacus is a
combination of l)oth. The
sul)serous Iminches accom-
j)any the c()r()nary vessels
in plexiform arraiiuement,
and ai-e studded with gan-
glionio eh^ments, single or
in groni)s. The termina-
tion of the nerves in the
muscle of the heart has not
yet been demonstrated.

(2) The Arteries. Their
walls are composed of at
least three layers, the innei'
of which — the infini<( — is
endothelium : the middle
— the media — smooth mus-
cle ; and the outer — the
ad rent if in — a connective-
tissue formation. These
three layers are verj- firmly
connected with each other ;
the relative thickness of
these coats varies greatly
with the size and the loca-
tion of the vessel. (See
Fig. 144.)

The inner coat is com-
posed of flat, nucleated
endothelia. exhibiting the
usual bioplasson reticu-
lum. These bodies are
elongated in the longitudi-
nal direction of the artery,
and in edge view appear spindle-shaped, owing to their middle

Fig. 144. — Wall of the External Car-
otid OF Man. Transverse Section.

E, emlotlit'lial layer, beneath which is a hyaline,
so-calleil elastic, layer; MM, smooth muscle in lou-
^ituiliual ami transverse section ; F, dense fibrous
connective tissue, with a network of broad elastic
fibers ; C, loose connective tissue supplied with capil-
lary blood-vessels. Magnified 200 diameters.

336 EPITHELIAL AND EXDOTHELJAL TISSUE.

broadest diameter at the seat of the imek'us. The separatino:
eeineiit-suhstauce is best demonstrated by the injecting of gehi-
tine, to which a two per cent, solution of nitrate of silver is added.
Upon treatment with distilled water and exposure to daylight, the
lines of the eement-sul)stance appear dark l)r()wn in color and
pierced by numerous tranverse light lines, which (see page 125)
correspond to the connecting filaments of li\'ing matter (" thorns"
or ''prickles"). Not infrequently dark bro's\^l dots or delicate
rings are visible along the brown line of the cement-substance,
varying greatly in nimiber in ditf ereut localities ; these are the
so-called stigmata.

In the smallest arteries, the arierloJes, there is an extremely
delicate structiu-eless membrane, next to the endothelia. The
two together have a fluted contoiu% and the cement-substance a
zig-zag appearance, e^adently on account of the contraction of
the middle or muscle coat. In larger arteries, the structm-eless
membrane is found to be considerably broader and fenestrated
— i. e., with numerous, irregularly distributed perforations ; in
still larger arteries, the fenestrated membrane is replaced by a
dense reticulum of elastic fil^rilla'.

In the largest arteries two more or less distinct layers are
found over the endothelium; the inner being the hyaline or
elastic meml)rane proper, the outer a reticulum of elastic fibrillae.

The niidiUe coat is composed of smooth, spindle-shaped
muscle-fibers, which in the terminal arterioles are present in one
layer only, twined around the vessel. In longitudinal sections
of arterioles, these fillers are easily recognized by their transverse
sections along the wall outside the endothelium. The nucleus
of the fusiform muscle-fiber, which is rod-like in front view,
becomes visible in the transverse section only when the middle,
broadest portion of the spindle shows its optical section. As the
caliber of the artery enlarges, the muscle spindles become aug-
mented, being very numerous in the larger arteries. Here, also,
a longitudinal layer of muscle spindles becomes apparent, out-
side of the circular layer ; but the longitudinal layer nowhere
reaches a high degree of development. In the middle coat of
larger arteries the bundles of smooth muscles are separated by
elastic fibrillte, and in the largest arteries by continuous mem-
braneous formations of elastic substance, which attain then-
highest development in the aorta. In this situation the lamella?
usually take an oblique course, and are connected uninterrupt-
edlv with the elastic reticulum above and lielow the muscle coat.

Kl'ITIIKLIAL AXh F.X ItoTII KLI M. TISSUE. 337

Accordin«j; to ('. Toldt, the nmscle-fibers of the middle coat
are waiitinjj: in tlie initial portion of the aorta, in tlie jmlnionary
artery, and in the small ai'tcrioles of the retina; in the aorta
descendens, the A. iliaca coninninis, and the A. poplitea small
nmsele hnndles, in an ol)liqne or a loncritndinal direction, are
interspersed l)et"\veen the eirenlar ones ; and in other arteries (A.
rensdis, lienalis, sperniatiea interna), at the inner boundary of
the muscle coat, scanty longitudinal bundles occur, which, by
some authors, are considered to belong to the inner coat. Some-
times, in the corresponding arteries of different persons, slight
differences are observed in the distribution of the muscles of the
ndddle coat.

The outer coat is composed of fibrous connective tissue, which
varies greatly, both in amount and density, in different vessels.
In the smallest arterioles it is only slightly developed, while in
the largest arteries it attains considerable breadth. In medium-
sized arteries, the muscle layer toward the connective tissue is
bounded by a hyaline, elastic membrane, which in the large
arteries is widened into a thick layer of dense fibrous connective
tissue. The bundles of this tissue are interlacing, and at their
boundaries marked by a coarse, well-developed reticulum, or
frame-work of elastic substance. This frame is denser in the
neighborhood of the middle coat than toward the peripheral
portion. The latter exhibits scattered bundles of smooth muscles
in a longitudinal aiTangement, and is gradually transformed into
loose connective tissue, which composes the sheath of the artery,
and carries a system of capillary blood-vessels, the so-called vasa
vasorum.

The development of arteries was studied by J. B. Greene, who
found that they are originally solid cords, composed of indifferent
or embryonal elements. The most central ones become vacu-
oled ; others are transformed into a flat layer to form the futiu-e
endothelia ; while the most external are elongated in shape, and
assume a circular arrangement, this being the first trace' of the
future muscle-fibers. (See Art. on menstrual decidua.)

(3) The Coats of Veins are similar in composition to those of
arteries ; but the elastic substance and the muscle tissue is less
developed in veins than in arteries. It is the middle coat, espe-
cially, which in veins varies most in breadth. This coat is also
comparatively more develoi)ed in the veins of the lower than in
those of the upper extremities. In the V. portae, cava ascendens,
and hepatica the muscle coat is only faintly defined, and its
22

338

EPITHELIAL AND ENDOTHELIAL TISSUE.

bundles are separated by broad layers of fibrous connective
tissue. A relatively large amount of muscle is found in the
middle coat of the veins of the spermatic cord. (Sec Fig. 145.)
The muscle coat is almost completely wanting in the system
of the V. cava descendens, in the veins of the nerve centers, and
also in those of the bones. Here the middle coat is composed of
delicate fibrous connective tissue, with more or less elastic fibers,
running in a cii-cular or oblique direction. The venous adven-
titial coat is likewise less developed than the arterial, but contains
a comparatively greater number of longitudinal bundles of
smooth muscle, so much so that in the V. porta^ and V. renalis
these bundles form an almost continuous layer. In the adven-
titial coat of the veins which empty into the heart, near their
cardiac orifices, we find a varying amount of striated muscle-fibers,
in a reticular arrangement, which are prolongations of the muscle
^f the h-^art

Fig. 145. — Blood-vessels from the Loose Adventitial Connective
Tissue op the Spermatic Cord of Man.

A, artery, with £, euaothellal aud covering lij-alioo layer; M, smootli muscle layer; 0,
adventitial layer ; F, vein, exhibiting tlie same layers as the artery ; C,' capillary blood-
vessels, composed of a single endothelial layer, with a surrounding delicate adventitial
fibrous connective tissue. Magnified 200 diameters.

The valves of the veins are reduplications of the inner coat,
with a well-defined elastic reticulum, especially on the convex
surfaces, and with a complete endothelial investment.

The cavernous bodies are veins or sinuses of greatly varying
calibers, freely anastomosing with each other; they are en-
sheathed by a dense connective-tissue capsule, which sends

EPITHELIAL AX/) KN DOTH F.IA A L TISHI'L. :5:ji)

numerous offshoots between the veins, and is in pai-t freely sup-
plied with smooth muscles.

Arteries and veins in specimens under the microscope nuiy be
distini»uished fi'om each other by the fact that arteries almost
always are empty, or contain only a few blood-corpuscles, while
veins, as a rule, hold a largfe amount of bh)od. Besides, the arteries
are found to be contracted, their inner coat has a fluted, coi-ruf^ated
outline, while the veins are more or less smooth in their inner
circumference. The wall of the artery is always broader than
that of the vein, owinjy to the presence of the muscle coat, which,
both in longitudinal and transverse sections, is well marked in the
former and but slightly marked in the latter. In transverse sec-
tions of veins, also, transverse sections of the longitudinal muscle-
fibers are often recognized. Another point of diffei-ence between
an artery and a vein, should the latter have a marked muscle
coat (see Fig. 145), is that the artery has a circular or slightly
oblong caliber, while the vein has an oblong, irregular, com-
pressed, or hour-glass shaped caliber. The adventitial coat,
likewise, is decidedly thicker in arteries than in veins, though
both may exhibit the nutrient capillary blood-vessels, the vasa
vasorum.

(4) The Capillar ies are composed of a single endothelial wall.
Their plexiform arrangement is best brought into view by the
injection of a stained, coagulating material. The density of the
reticulum greatly varies in different parts and organs of the
l)ody. The closest reticulum is found in the lungs ; the densest,
and at the same time broadest, reticulum in the liver. In the latter
organ, the caliber of the vessels show marked variations in size
in comparatively small territories of the lobules ; this is evidently
due to a difference in the diameter of the liver epithelia in differ-
ent stages of their activity. In the kidneys, too, there are striking
differences in the calibers of the capillaries, some of which (the
so-called vasa recta) attain the size of veins.

S. Strieker was the first to point out the fact that the wall of
the capillaries is endowed wdth vital properties, and especially
with that of contractility. Before him, the capillai'y walls were
considered to be only an elastic membrane. NoT)ody can doubt,
who has carefully observed capillaries in different situations,
that during life the endothelial wall exhibits marked changes,
according to its state of contraction, to the functional activity
of an organ, and to the age of the individual. The injection of a
colored material from without renders these differences, as a

340 EPITHELIAL AND ENDOTHELIAL TISSUE.

matter of course, to a great extent imperceptible. Capillary blood-
vessels are by no means permanent formations, but, according-
to the necessity of their vital activity, they are produced and
destroyed — i. e., transformed into the connective tissue from
which they have originally sprung. That, with advancing age, a
number of capillaries are transformed into bone, I have demon-
strated (see page 236), and similar instances are found in all
varieties of connective tissue.

All capillaries are surrounded by a delicate light rim, which
is traversed by minute spokes of bioplasson, interconnecting the
wall of the capillary with the adjacent tissue. This perivascular
space, which certainly contains a liquid, was erroneously termed
a lymph-space, because colored liquids can be forced into it from
without by parenchymatous injection. Similar spaces, however,
exist around all bioplasson formations and around the territor-
ies of connective tissue (see page 132), but they bear no relation
to the lymphatic system. It will be seen that successful injec-
tions have demonstrated the presence, in the lymph capillaries,
of an endothelial wall, similar to that of the blood capillaries. As
both are permeable to the liquid and solid constituents of the
blood and lymph, the assumption of an ensheathing lymphatic sys-
tem around the blood-vessels is quite superfluous. Around the
capillary blood-vessels wliich lie close to- the arteries and veins
there is often found a continuous layer of connective tissue, the
so-called capillary adventitial coat. A distinct coat of this kind
is found around all capillaries of the central nervous system
(His). According to Boll there is no reason for terming this
investing sheath, which is rendered very plain by parenchyma-
tous injection, a lymph-sheath.

In the vicinity of capillaries, especially in the loose connective
tissue, large, coarsely granular plastids are often found, the
'' plasma-cells" of Waldeyer, the significance of which is not yet
fuUy understood. Here, however, is the place of the most intense
nutrition, where the first and most prominent changes occur in
the process of inflammation.

Upon being injected with a solution of nitrate of silver, the
capillaries exhibit in many localities an elongated frame of brown
cement-substance, with a varying number of stomata and stig-
mata. The flat eudothelia, being broadest in their middle portion,
where the nucleus is located, exhibit a spindle-shape both in lon-
gitudinal and transverse sections of capillaries. In numerous
cases, however, no endothelium is rendered visible, even with the

F.l'irUF.LIM. AM) h'Xnornh'LIM. TISSUE. WAX

silver stainin*;, and the capillary appoars as aeontiinious layci- of
hioplasson, which lici-c and there is slit»:litly tliickciicd. This
Ix'comi's coiuprchciisihlc through the facts taufjfht by the; history
of development of the capillary l)h)od-vessels.

Nerves have often been demonstrated in the walls of capil-
laries by means of ^old-staining. They appear as a deli(;ate,
beaded reticnlnm. rnnnin^ in the cement-snbstan<H', in the same
manner as in epithelia. (See paj^e 324, Fig. 140.)

Peculiar vascular formations are the cocci/f/cal and carotid '^ (/lands," and
the plcjiis- ehoroidci. They are composed of convolutions of capillary blood-
vessels, with vesicular club-shaped or serai-globular prolongations, in connec-
tion with the caliber of the capillary. Neither the coccygeal nor the carotid
gland are e)>ithelial or glandular formations, therefore the word "gland" is a
misnomer in this connection. C. Langer tliscovered in the mucosa of the palate
and throat of frogs semi-globular prolongations of the capillaries, often with
anastomosing the caliber of the capillary by means of a narrow pedicle. He
considers these formations equivalent to capillary loops.

l}f'veh)pmpnt of CapilJuries. S. Strieker (LSOf)) first proved that
the capillaries are originally solid strings, either connected with
the wall of an already formed capillary, or representing solid,
clnb-like ontgrowths from this wall. These solid strings become
afterward excavated, va(?noled, and the originally solid wall of
the capillary is differentiated finally into endothelia.

My owai researches corroborate this discovery of Strieker. I
have seen solid, clnb-shaped formations in the middle of a
medullary space, which were new formations produced by the
retrogression of cartilage tissue to its embryonal condition. (See
page 246.) I also have observed that the originally solid club or
cord-like formations become vacuoled even before a connection is
established with older blood-vessels, and that in the vacuole
unchanged masses of bioplasson remain, which I have called
htematoblasts, because they are the future blood-corpuscles. I
made similar observations in the study of the process of inflam-
mation in different varieties of connective tissue, aU of which go
to prove that a capillary is originally a solid mass of bioplasson,
which by vacaolation becomes hollowed, while some particles of
bioplasson are furnished with haemoglobin, and converted into
colored blood-corpuscles. In 1873, I said that wherever a trans-
formation of one tissue into another takes place, either as a
normal process, or as the result of inflammation, a new forma-
tion of blood-vessels and blood-corpuscles invariably occiurs as a
part of the process. The wall of the newly formed capillary is

342 EPITHELIAL AXD ENDOTHELIAL TISSUE.

at first solid — in other words, the bioplasson is in the juvenile
condition. Later, the solid bioplasson divides into a reticulum,
with, in the center, solid masses, termed nuclei. At the periphery
the cement-substance is formed, though this, owing to the pres-
ence of the connecting filaments (''thorns''), never completely
separates the single endothelia into individual cells. Thus, the
wall of the capillary, even after the formation of endothelia,
remains a continuous layer of bioplasson, endowed with con-
tractility and with the capacity of growing, especially in the
inflammatory process. In retrogression of the capillaries the
hollow bioplasson is first solidified, then breaks up into medul-
lary elements and gives rise to connective tissue, from which,
under all circumstances, the capillaries have originated.

Th. Schwann * found in the germ-membrane of the o^-um of the chicken,
thirty-six hours after hatching, cells which, by elongation in different direc-
tions, became stellate. He called these cells the cells of capillary vessels,
and considered the blood-corpuscles as young cells formed in the cavity of
the capillary vessel cells.

C. Rokitanskyt knew that in certain morbid processes, especially in the
growth of cancer, blood originates in cells which had become tubular or club-
shaped. The j)rolongation of the cells he considered as a beginning new for-
mation of blood-vessels. He also maintained that a so-called insular new
formation of blood took place in the process of inflammation.

S. Strieker t asserted that the capillary tube is a hollowed out protoplasma
endowed with many of the characteristics of life ; that a solid thread, first
simply an offshoot of a capillary vessel, afterward becomes hollow ; that in
the tail of the tadpole there are vessels filled with colored blood-corpuscles,
terminating at either end in the shape of extremely delicate solid processes.

E. Klein $ demonstrated that in the germinal disk of the chicken embryo,
in the first half of the second day of hatching, some elements of the middle
germinal layer exhibit vacuoles. These vacuoles, he asserted, were the first
formations of blood-vessels, and that from its protoplasmic walls masses are
separated, partly colored and partly colorless — the blood-corpuscles. In
other cells of the same genninal layer, occasionally multinuclear, he observed
in the center an endogenous formation of blood-corpuscles, while the peri-
phery of the cell was transformed into the endothelial wall of the vessel.

My own researches 1| have resulted in the conclusion that living proto-
plasma, in the condition termed "haematoblastic," — viz.: in a juvenile con-
dition of development, — is the material from which originate both the colored
blood-corpuscles and the wall of the blood-vessels.

* " Mikroskopiache Untersuchungen," etc., 1839.

fHanrtbiicli rler Alljr. PatliolDg. Anatoinie," 1846.

t ".Sturtien iiber den Ban unrt das Leben der capillart-n BlutgefiissP." Sitzungsber. d.
Wiener Akad. d. Wissenscli., 1865.

? " Das mittlere Keimblatt in seinen Beziehunffen zur Entwicklunfr der ersten BlutgefSsse
u. Blutkiirperchen im Huhnerembryo." Sitzungsber. d. Wiener Akad. d. Wissensch., 1871.

II " Ueber die Ruck-u. Neubildung von Bliitgefassen im Knocheu u. Knorpel." Wiener
Modi/. .lalirbiicher, 1873.

KVITITFLTAL AXJ) KXDOT/H:!.! A L TISSTK. 34:3

The Lymphatic System.

Duriiiii- the liist liftccii years iiiiiiiy ci-i-oiicous views coii-
oernin^r the lyinj)hiiti(' system liave arisen, due to the method
of stiulyiii<j — viz.: by " pareneliyiiuitous injection" of colored
liquids. Perforations were made at random into the tissues of
the body, and li(iuids Avere then forced in from without. The re-
sults and views obtained by this means are only worthy of being
forjrotten. On the other hand, careful injections of the lymphatics
themselves, by Teichmann, Langer, Sappey, and others, have
shown conclusively that the system of lymphatics is a closed one,
just as that of blood-vessels. Throughout the lymph-ganglia,
the spleen, and the lymph tissue in general, erroneously
termed ''adenoid tissue," lymph-vessels probably do not exist.
The ditfieulties in rendering the lymphatics distinct by injection
are very great, on account of the delicacy and transparency of
their walls, their colorless contents, and the presence of valves
arranged in the same manner as in veins.

The lijniph-vessels form a reticulum, in the average wider than
that of the blood-vessels, exhibiting in its peripheral ramifica-
tions, besides loops, pointed or club-shaped terminations. Lymph-
vessels are characterized by irregular excavations and sinuses,
and run either parallel with the blood-capillaries or independ-
ently of them. They are, like the blood-vessels, found only in
connective-tissue formations. The walls of the lymph-capiUaries
are composed of a single endothelial layer, whose elements, as a
rid.e, are larger than those of the blood-vessels. Often, there is
no other investment to be seen, and the lymph-capillaries in this
case have the appearance of being channeled in and supported
by the adjacent tissues. The lymph-capillaries are destitute of
valves ; but the collecting ramules are always found to possess
valves which produce constrictions of the vessel, while close
above the valve, in the more central portion, there is a widening
of the caliber. The ramules accompany the arteries, often in the
shape of a reticulum, which is also found around the veins,
though less developed. The larger ramules exhibit a delicate
investing elastic layer immediately above the endothelia, and
with the increase of the caliber of the lymph-vessel this invest-
ment assumes a fibrous structure, and is supplied with smooth
muscle-fibers. A distinct stratification of the wall is apparent
only on those lymph- vessels which, in the extended condition, have
a diameter of 0.8 to 1 mm. (C. Toldt). Here, three layers are

344 EPITHELIAL AND ENDOTHELIAL TISSUE.

discernible, analogous to those of blood-vessels : the most inter-
nal is the endothelial, with an underlying delicate connective tis-
sue, which, as a rule, holds a number of elastic filjrillae ; the
middle coat is composed of eir(!ular smooth muscles, inside of
which are sometimes found longitudinal fibers, and the outer
layer is fibrous connective tissue, with interspersed bundles of
smooth muscle-fibers. The reticulum of elastic fibrillae consti-
tutes a comparatively broad layer in the walls of the thoracic
duct; here, also, the oblique muscle bundles of the adventitial
coat are most distinctly marked.

In the lower vertebrates the lymph-vessels are often found
dilated into lymph-sinuses, which, in part, are under the control
of muscles — ''lymph-hearts'' (J. Miiller). Many of the lymph-
sinuses empty directly into larger veins. In mammals, such
lymph-sinuses are of doubtfiil occurrence, though it is generally
held that the lymph-follicles in the small intestine of rabbits are
surrounded by such sinuses.

Von Recklinghausen discovered that the peritoneal cavity is
in direct communication with the lymphatic system at the ten-
dinous portion of the diaphragma. The peritoneum is expanded
over the large lymph- vessels of this portion, being lined by com-
paratively small endothelia, the cement-substance of which is
more or less closely perforated with minute openings, the stomata
and stigmata. The nuclei of the endothelia are arranged in the
form of a wreath around the stomata, and larger stomata are
again surrounded by a wreath of very small, regular endothelia.
Through these openings dissolved or finely granular colored
substances, if injected into the peritoneal cavity, are carried
directly into the lymphatics of the diaphragm (C. Ludwig,
Schweigger-Seidel).

The method of Ludwig and Schweigger-Seidel ("Arbeiten aus der Physio-
logischen Anstalt zu Leipzig," 1867) is as follows: The abdominal cavity of
a rabbit which was bled to death is opened ; the V. cava, the aorta, and the
oesophagus are tied to the vertebral column by means of a common ligature,
and the coi-pse of the rabbit is di\4ded into halves by an incision made below the
diaphragma. The upper half is suspended, the head downward, in such a
manner that the diaphragm assumes a goblet shape. A certain amount of
water, holding dissolved Prussian blue, is poured in this goblet, and by arti-
ficial respiratory movement the diaphragm is carried up and doAvn for several
minutes. Next the peritoneal surface of the diaphragm is washed, and alco-
hol poured over it, in order to render the Prussian blue insoluble and fix the
tissues. After excision, the center of the peritoneal surface shows white ten-
dinous tracts bounding blue tracts. These latter are the larger lymphatics,

Kl'I I IIKLIAL AM) F.S IXHII KIJ A L TISSUE. :}4r>

and the abovc-iiamctl ohsorvcrs fonsidcreil them clefts between the tendinous
Jmndles. On the ph'ural surface is observed a reticulum of lymphatics, which
is blued by injection, the small vessels f^-adually passiuf? into lar^^er lymi)h-
vessels. The colored liqnid has penetrated the lymphatics through openings
in the central portion of the peritoneum covering the diaphragm. The
stonuita present in this situation, and which are surrounded by small globular
elements, were termed l\Tuph-wells by Kanvier.

Dybkowski found similar openings also in the endothelial
investment of the parietal pleura ; these o])enings are confined
exclusively to the intercostal spaces, while in the pleura covering
the ribs the stomata are absent. By the injection of colored
substances into the pleural sac, results are obtained simOar
to those in the peritoneal cavity. The subjacent lymph-vessels
in all these localities are distinctly marked by an endothelium,
therefore are not simply interstitial tissue-clefts. The assertion
of Von Recklinghausen that the connective tissue is pervaded by
spaces and canals, destitute of walls of their own, and thought to
be the roots of the lymphatic system, is erroneous, as proved in
the chapter on connective tissue. Every space rendered \nsible
by the staining wath nitrate of silver contains a bioplasson })ody
demonstrable by staining -with chloride of gold. The apparent
connections between the ^' juice-canals '• of the connective tissue
and the lymph-vessels proper, in specimens stained with nitrate
of silver, althoiigh rarely seen, are explicable hy the fact that
neither the bioplasson bodies nor the IjTnph- vessels take up the
sUver stain. Observers agree, however, that at the periphery of
the connective-tissue c<n'puscles and of the territories there are
narrow spaces containing a liquid ; but we are not justified by
any facts in connecting these spaces with the lymphatic system.

Lympli-ganglia and Lijmpli-tissue. These are peculiar forma-
tions of the mj^xomatous connective tissue, which are closely allied
to the lymphatic system. Their characteristic feature is a deUcate
reticulum, the meshes of which are crowded with lymph-corpus-
cles— /. ^., bioplasson bodies exhibiting all stages of develop-
ment, from a small, homogeneous granule to a nucleated plastid,
similar to the colorless blood-corpuscle (see page 105 and Fig.
31). This tissue is widely spread throughout the submucous
layers, and reaches its highest development in the youngest
individuals. It is arranged in conglomerated heaps — the so-called
lymph-follicles — in the tonsils, the pharynx, the base of the
tongue, the wall of the stomach, the submucous layer of the
intestines, in the lymph-ganglia, along the lymph-vessels in

346 EPITHELTAL AND ENDOTHELIAL TISSUE.

regular localities, in the thymus, and in the spleen. Prol)al)ly
the thyroid body and the suprarenal capsule likewise belong to
this group. Single heaps of this lymph-tissue are termed lymph-
follicles ; compound formations of lymph-follicles bear the name
of lymph-ganglia. In the spleen of man the lymph-follicles
(Malpighian corpuscles) are elongated, and they are everywhere
in close relation with the arteries and arterioles.

The lymph-follicles are, according to generally adopted views,
the widened beds of the lymph-vessels and brought into connec-
tion with the lymph either by being surrounded by lymph-
sinuses or by a dense reticulum of lymph-vessels, while the
interior of the lymph-follicle is destitute of lymph-vessels. Every
lymph-follicle, moreover, is encircled by a rich reticulum of
blood-vessels, which send a comparatively small number of capil-
lary loops into the interior of the follicle, these sometimes not
reaching its central portion.

The lymph-ganglia are composed of more or less globular Ijimph-
foUicles, their prolongations, the foUicuIar cords and the interfol-
Jicular strings, located between the two-named formations. The
follicles and follicular cords abound in lymph-corpuscles, having
a relatively delicate and scanty myxomatous reticulum, while in
the interfollicular strings the myxomatous tissue is largely de-
veloped, and the lymph-corpuscles are less numerous. Besides,
the interfollicular strings hold numerous blood-vessels, while the
follicular formations exhibit a comparatively limited vascular
supply. The interfollicular strings have also numerous lymph-
vessels, while the follicles have none whatever. (See Fig. 146.)

The lymph-ganglion is inclosed by a dense fibrous connective-
tissue capsule, whose outer parts blend with the surrounding
loose connective tissue, which is supplied with a varying amount
of fat. In the capsule, and in the coarser offshoots, bundles of
smooth muscle-fibers are found, which in the lymph-ganglia of
cattle form a continuous layer (Von Recklinghausen). The
fibrous capsule sends prolongations into the depth of the follicle,
which soon changes into a myxomatous reticulum. In the inter-
follicular strings the myxomatous tissue is well developed, has
oblong nuclei on most of the intersecting points, and contains in
its meshes comparatively few lymph-corpuscles.

The interfollicular strings ensheath the follicles, which, as a
rule, are formations consisting of a large globular or pear-
shaped mass of lymph-corpuscles, and are found at the periph-
ery, the so-called cortex of the ganglion. The globular follicles

Kl'llUEl.lM. AX J) KMkHUKLIAL TlSSl'E

;U7

seud jji'olonpitions — the follicular cords — into the middle j>or-
tion, the so-called nirditlln of the ^anj^lioii, and liere the follicular
cords freely unite to form a coarse reticulum, which is more
or less distinctly nuirked from the surrounding interfollicular
strinjifs. The portion of the lymph-ganglion giving exit to the
lymi)h-vessels is characterized by a relatively compact forma-
tion of fibrous connective tissue, inclosing elongated, empty
spaces. This is the so-called hilus-stroma of His. The connect-
ive-tissue trabeculse are known to be the carriers of the l\nnph-
vessels, which are in o])en commnnieation with the lymph-spaces
or sinuses around the follicles, and in the follicular cords. All
these spaces are lined by a single endothelial layer, and they are

^^&^ifefe-Si&^~:¥?i2a^is;-£«®^^^ iii^

Fig. 146. — Lymph-ganglion. Transverse Section.

C, connective-tissue capsule, outside with fat-lobules, FA ; FO, lymph-follicle : FS.
follicular cord ; IF, interfollicular string, with numerous blood-vessels. Magnified 100
iUanieters.

also in direct connection with the meshes of the m^Tsomatons
reticidum. An endothelial investment has been found only on
the larger trabecule of the myxomatous reticulum. The meshes
of the reticulum of the interfollicular strings contain compara-
tively few l\Tnph-corpuscles, while the meshes of the extremely
delicate reticulum of the follicles and the follicular cords are
crowded with them.

Two or more afferent lymph-vessels enter the ganglion on
one pole and di^dde into a number of branches, the endothelium

348 EPITHELIAL AND ENDOTHELIAL TISSUE.

of which furnishes the investment for the lymph-sinuses. The
sinuses unite to form what Toldt calls the " terminal sinuses."
From these sinuses two or more efferent vessels arise, which by
anastomoses gradually decrease in number.

The arteries penetrate the hn^nph-ganglion both at the periph-
ery and at the hilus. Their ramules occupy the middle of the
interfollicular strings ; these also contain a few capillary blood-
vessels, all supplied with a distinct adventitial coat. The arteri-
oles form a wide capillar\^ net- work, traversing the follicles and
follicular cords, and giving rise to the veins, which accompany
the arteries. The capillary system of the follicles and follicular
cords is, to a certain extent, independent of the capillaries of the
interfollicular strings. The capillaries of the lymph-gangha are
easily permealjle to colored liquids iujected iuto the artery. The
reasons for this have not been fuUy explained.

The thymus body is a lymph-ganglion belonging especially to
fcetal life. It reaches its highest state of development during
the first two years, remaining stationary up to the tenth year,
and at the time of puberty it has almost entii*ely lost its follicular
sti'ucture. The delicate fibrous investment of the thymus body
sends numerous prolongations into the interior, giWng to it a
more or less lobular appearance. The follicular formations are
less distinct in the thj-mus than in other hanph-ganglia, and are
more closely aggregated at the periphery of a lobule than in its
center. Numerous small arteries enter the th^nnus body at its
periphery- ; a few larger ones at its posterior portion. The course
which the hnnphatics take in the interior of the th\Tnus is
unknown. In the period of its involution peculiar concentrically
striated corpuscles (Hassal) make their appearance, kindred to
ihe amylaceous corpuscles of the brain. Apparently, these are
developed from the walls of the capillaries, most probably from
their endothelia.

The thyroid body, in the earliest periods of embryonal develop-
ment, exhibits a glandular structure — /. e., is composed of acini,
.lined by cuboidal epithelia ; the acini are closed on all sides and
no excretors^ duct can be discovered. This body, in all probabil-
ity, is an elongati<»n of the outer germ-layer — the epiblast. At
the time of bii'th, the epithelial structure is often still preserved.
Sooner or later, however, the epithelia are transformed into indif-
ferent or embryonal corpuscles, exhiliiting the characteristics of
hnuph-corpuscles. We meet with small, homogeneous globules,
and also with larger ones of the size and the structure of nuclei,

Kl'lTUI'JJAL AM) i:M)()Tm':LIAI. TISSUE.

349

and still larger ones, n-jji-csciitiii^ globular, miclcatrd plastids.
Simultaneously with this ivcui-i-cnci' of the embryonal condition,
even in children, many of the lymph-corpuseles perish and are
transformed into a homofjeneous, viscid, so-called (!olloid sub-
stance, which, in thyroid bodies of adults, is almost invaria])ly
'found in the closed spaces, now termed alveoli. The lymph-cor-
puseles are often arranged in the shape of a wreath along the
wall of the alveolus, and irregular clusters of these corpuscles are
found scattertnl throughout the colloid mass. The stages of
transfornuition of the plastids into the colloid substance can easily
be traced. (See Fig. 147.)

M.

Fig. 147. — Thyroid Body of Adult.

F, connective-tissue frame, carrviug numerous blood-vessels; L, l.vmpli-corpuscles ; Q,
colloid mass. Magnified 500 ilianieteis.

The connective-tissue capsule of the thyroid body sends
numerous prolongations into its depths, which constitute the
walls of the alveoli. A striking feature of this formation is the
great number of blood-vessels and lymphatics which penetrate
its interior. The significance of this ])ody is, however, not under-
stood.

The suprarenal capsule, is composed of two layers — a cortical
and a medullary layer. In the former we see radiating rows of
polyhedral bodies, ha\ang the appearance of epitheha, which
often contain fat-granules. The connective tissue throughout
this body is an offspring of the outer capsule, and is seen between
the rows of the polyhedral bodies ; near the boundary line of the
cortical laver it forms a delicate reticulum, characterized liv a

350 EPITHELIAL AND ENDOTHELIAL TISSUE.

varying amount of a brown, granular pigment. The myxoma-
tous reticulum in the medullary portion contains in its meshes
lymph-corpuscles varying greatly in size. Both in the medulla
and the connective-tissue capsule there are numerous ganglionic
nerve elements (Von Brunn) which are in connection with the
sympathetic nerve, branches of which, in large number, penetrate *
the suprarenal capsule. This organ has likewise a large supply
of blood-vessels. Its development and functions are still physi-
ological puzzles.

The sjyleen, in its structure, is closely allied to the lyniph-gan-
gHa, though its relation to the lymphatic system is by no means
clear. Like the lymph -ganglia, the spleen has also a connective-
tissue capsule sending numerous offshoots into the depths of the
organ, where it produces a delicate myxomatous reticulum. The
meshes of this reticulum contain a comparatively small amount
of lymph-corpuscles, while these form larger globular heaps, sim-
ilar to the follicles of the lymph-ganglia, — the so-called Malpigh-
ian corpuscles, — and elongated tracts, similar to the follicular
cords — the so-called pulp-cords. The connective-tissue capsule
has for its outer investment the endothelia of the peritoneum ;
in many mammals it contains a large number of bundles of
smooth muscles, which also pervade the mass of the spleen. In
man, the number of fibers of smooth muscle in this organ varies
greatly, although small bundles are unquestionably found in many
cases. The connective-tissue septa of the spleen are in union
with the outer capsule, and produce branching and anastomos-
ing trabeculae throughout the pulp. These trabeculae carry the
arteries and veins, both of which enter or leave the spleen at dif-
ferent points, usually far apart.

The arterioles in most mammals show a distinct adventitial
coat, which is crowded in its whole extent with lymph-cor-
puscles, so much so that each pulp-cord is pierced in its center
by an arteriole. In man, the lymph-corpuscles around the arter-
iole are accumulated in lymph-follicles, varying in size, and either
uniformly surrounding the vessel or attached more or less eccen-
trically to one side of the vessel. A favorite seat of these so-
called Malpighian corpuscles is the point of ramification of the
arteriole. In mammals' spleens which abound in muscles, — f. i.,
in the badger's spleen, — we observe bundles of smooth muscle-
fibers accompanying the artery and surrounding the follicle,
which is in connection with the layer of lymph-corpuscles in the
adventitia of the artery. (See Fig. 148.)

EriTllKLIAL AM) J'JXJJOTUKJJAL TISSUE.

351

Tlu' myxomatous rt'ticulum of the pulp-cords of tlie sj)l('('n
contaius iu its moshes lymph-('()r])us('les in ditfcnMit staj^es of
development and multinuclear ])ioi)lasson masses; also a varying^
numl)er of pi«;;ment granules, either scattered in the lymph-cor-
pusch's or grouped in the shape of dark })r()wn pigment clusters.
In accordance with the view that red l)lood-corj)uscles ()i-ij2,"inate
in lymph-corpuscles, ahnost all observers describe lymph-cor-
puscles as containing colored blood-corpuscles ; others maintain
the origin of these corpuscles from the endothelia. Su(^h views,
however, are erroneous, and Johnstone has demonstrated the

Fig. 14S.

-Follicle of the Spleen of a Badger, in Connection
WITH an Artery.

L, lyini>li-f()Ili(lf ; A, artery, penetratiug tlie follicle ; ^4 rf, adventitial coat of the artery,
crowded with l.vuipli-corpusclea ; 3/, muscle-stiinss of the spleen, acconipauying the artery;
V, blood- and Ij-niph- vessels in transverse section; P, clnsters of pigment In the tissue of the
spleen. Magnitled 500 diameters.

source from which the colored blood-corpuscles arise, both in the
l\Tiiph-ganglia and in the spleen — here, especially, in large num-
bers. (See page 105.), The significance of the multinuclear
bodies is unknown, and there is no reason to term them the
graves of the colored blood-corpuscles.

The arteries send numerous branches into the adventitial
lymph-tissue and the lymph-foUicles ; they finally divide into

352 EPITHELIAL AND ENDOTHELIAL TISSUE.

terminal branches, which produce delicate capillaries for the
supply of the connective-tissue septa and for the pulp-cords.
The veins arise from these capillaries, and represent vessels with
thin endothelial walls, susceptible of a high degree of dilatation
(Billroth). These vessels traverse the interstices between the
pulp-cords and the connective-tissue trabeculae, and produce
tassel-like formations, which finally collect into larger veins. A
number of observers maintain that the arterial capillaries are
directly connected with the capillary veins ; that therefore the
vascular system of the spleen is closed eveiywhere. Wedl even
admits a direct communication between arteries and veins. Others
believe in the presence of lacunae, destitute of walls of their own,
interposed between the terminating capillaries of the arteries and
the roots of the veins. The latter view is not sufficiently sup-
ported, for the walls of the capillaries of the spleen, as well as
those of lymph-ganglia, are easily permeable to stained liquids
injected from without. The important question as to the termi-
nation and origin of the capillaries is unsettled.

The origin of the lymph- vessels is also a much-discussed ques-
tion. Tomsa considers the lacun* as the roots of the lymphatics,
l^ecause he succeeded in injecting them through the lymphatics.
Probably the relations are the same as in the lymph-ganglia.
Besides the lymphatics of the pulp, there are others in the cap-
sule, and Wedl found in the spleen of the horse and the sheep
two layers, the superficial being composed of narrow capillaries
and wide meshes, the deeper of large, sinus-like capillaries, fi-eely
anastomosing yAih. each other.

The manner in which nerves terminate in the lymph-ganglia
and in the spleen is unknown.

I have thus briefly presented the views of other observers,
because, on account of the lack of personal researches, I have no
positive knowledge concerning the structiu-eof the lymph- ganglia
and the spleen.

XI.

INFLAMMATION.

HISTORICAL SKETCH. The clinical features of inflammation have been"
well studied ever since Hippocrates's time, but the interpretations of
its appearances under the microscope have passed through varying phases
during the last forty years. The views regarding the nature of the iniiaTn-
matory process have undergone changes corresponding with the advanced
knowledge of biological facts. Two main conceptions of this process have
controlled the observations made by means of the microscope — \nz., the
theories of humoral and cellular pathology.

C. Rokitansky,* the founder of the humoral pathology, originally consid-
ered inflammation to be a disturbance in the vascular system, a disease of the
blood, whose mixture, the "krasis," gave a tj^jical character to the nature of
the inflammatory process. The greatest stress was laid on the exudation, a
liquid coming from the blood-vessels, therefore a modified plasma of the
blood. The favorite experiment at that time was tlie production of an arti-
ficial inflammation in the web-membrane of the frog. This apparently showed
all the phenomena of inflammation. The membrane of a living frog, care-
fully extended over a cork ring and held in position by pins, exhibited dis-
tinctly and beautifully the blood-vessels and the cun-ent of the blood, marked
by the rushing blood-corpuscles. Upon applying an irritating agent to the
web, iisually a drop of concentrated liquor ammonia?, striking changes
occun-ed in the curi-ent of tlie blood : first, an irregularity in the cmrent, an
undulation ; next, a slowing, and, finally, a stoppage of the current in the
in-itated vascular districts. This "stasis " was considered the essential phe-
nomenon of the inflammatory process. Simultaneously an inundation and
swelling of the surrounding tissue was observed, owing to the exudation. All
the newly appearing corpuscles, including both the inflammatory and the
pus coi"puscles, were termed exudation corpuscles, and, in accordance with
the cell-theory established by Schwann, were thought to have originated
from the exuded plasma of the blood, in a manner termed primordial genera-

•>■ " Handbiich iler Allgemeiueii Patliologisclien Anatomic, " Wit'u, lSi6.

23

354 INFLAMMATION.

tion (Urzcuguiifj), which means a new formation of cells from a liquid con-
taiuing no cells.

The reason for the dilatation of the capillaries, observed in the stage of
stasis of tlie blood-current, was at that time a question much discussed, but
never satisfactorily answered. Briicke's view — that the capillaries, after a few
intense contractions, became paralyzed — was accepted as the most probable.
The newly formed cells of the effusion, according to the theory of humoral
pathology, gave rise to new tissues as well as to the formation of pus. The
exudate itself was thought to become organized, and to prodiu-e pseudo-mem-
branes or hypertrophy of the inflamed tissues.

C. Rokitansky * afterward changed his views concerning the origin of the
inflammatory new formation. This great observer announced, in contradiction
to the views of Virehow, that, in inflammation, proliferation comes not only
from " comieetive-tissue cells," but also from "intercellular substances " ; that
the latter also increase and give rise ±o new formations. It will be shown later
that this view, at that time not understood, is entirely correct, and that since
1873 we have obtained facts which establish it on a firm foundation. The
theory of humoral pathology was shaken by R. Virehow. t This investigator
asserted that the blood-vessels take but little part in the inflammatory
process. He based his conclusions upon observations made by His in the
inflamed cornea, and the obsei-vations of Redfern in inflamed cartilage, both
tissues having no blood-vessels, yet becoming greatly changed by inflamma-
tion. The only active parts of the connective tissue, according to Virehow,
are the cells, which, after attracting the exudation from the blood-vessels,
being over-nourished, enlarge, divide, and subdivide, and finally give lise to
the inflammatory new formation, from which originates new formation of
connective tissue, hyperplasia, as well as pus. The theory that cells arise
from a plasma was no longer maintained. Virehow held that an exudation
could never organize a tissue, and that all new cells must necessarily be the
offspring of former cells. The new formation of cells, according to Virehow,^
starts fi'om the nucleus, which is first di\aded, and the "cell-body" is after-
ward split up into new cells.

The cellular pathology was based on these fundamental assertions of
Virehow, and it is certain that the gi'eat progress made in biological knowl-
edge in our day originated from these views, which gradually became the
leading ones, and are so even at the present time. That the cellular patho-
logical views are, however, not fully con-ect, I shall endeavor to demonstrate
later.

J. Cohnheim, ^ in IS (ill, announced a new theory regarding the inflam-
matory process, foimded upon the fact that in the exposed mesentery of the
frog an emigration of colorless blood-corpuscles takes place from the capillary
blood-vessels and the smallest veins. The history of the theory of the emi-
gration of blood-corpuscles from blood-vessels is briefly as follows :

Waller,|| in 184(), was the first who maintained having actually observed

* "Ueber das AiiswacUseu iler Binclegewelj.ssiibstanzen u. die Bezielimi^ desselbcn zur
Eutziindiiiig." Sitzungsber. d. Wiener Akad. d. Wissenscli., 1854.

t " Ueber Parenchyiiiatose Entziiadung," Virchow's Archiv, Bd. iv., 18r)2.

t "Ueber die Theilung der Zellenkerne," Virchow's Areliiv, Bd. xi. Celliilarpatbologie,
1871.

i " Ueber das Verhalteu der flxen Bindegewebskoiperclieii, bei der Entziiiiduiig."
Virchow's Archiv, Bd. xlv.

II Philosophical Mayazin. Two successive publications : 1840, J., p. 271 and 397 ; TI.,
p. 398 et sc(i.

ISFl.AMMATION. 855

tlie emiffi'iitioii of colorloss Mood-corpuscles. Accordiiif; to his view, the wall
of tlu> blood-vessel in the exposed and expanded mesentery and the tonf^ie .of
toads boeonies perforated in the circumference of the corpuscle lying next to
it, and the aperture in the wall left by tlie cori)U8cle is closed })y the
restorative power of the blood. That a real emigi'ation takes place was a
mere conclusion of his, imd so was the assertion that the emigrated colorless
blood-corpuscles were the iiukiis- and pus-corituscles, which first appear along
the walls of the blood-vessels.

S. Strieker,* in ISli;", ohserv<Ml in tii(l|n>lcs, iiniiiohilizcd by cunira,
colored blood-corpuscles, whicli were incarcerated in the wall of a ca})illary
l>lood-vessel, so that a portion of the corpuscle was inside, another portion
outside the cai)inary, and both portions were connected by a slender neck
within the wall of the vessel. He concluded that the red blood-corpuscles
conld pass the wall of the vessel witliout a rupture, in a manner termed
"diapedesis" by foi-mer pathologists.

J. Cohnheim,t in 18157, asserted that an emigration of colorless blood-cor-
puscles actually occm-s, he haviiig observed these bodies to pass through tlie
wall of the vessel. He saw that the inner ])ortion of the corpuscle decreased and
the outer gi-adually increased in size, then that tlie corpuscle was attached to
the wall by means of a thin pedicle, and finally detached entirely from the outer
wall. Unfortunately, this observer came to the conclusion that the emigration
of colorless blood-corpuscles is the principal factor in the process of inflam-
mation, and that the eutii-e mass of inflammatory corpuscles is nothing more
than an aggi-egation of such emigi-ated corpuscles, while the tissue itself
simply perishes, and its elements take no part whatever in the inflammatory
process. A few authors have accepted this view of Cohnheim. They have
spoken again of an organizing exudate, meaning the corpuscular elements of
the blood, and had they but known whence came this enormous quantity of
inflammatory corpuscles, the whole process of inflammation would have been
very clear and simple to them.

S. Strieker t has, since IS 70, strenuously opposed the views of Cohnheim.
He demonstrated that each of the former theories contained some truth, and
that from a combination the whole truth can be deduced. He proved tlie
necessity of the presence of blood-vessels and nerves for the origin of inflam-
mation, agreeing with the theory of the humoral pathologists, and showed that
the connective-tissue cells themselves participate actively in the inflammatory
process by swelling, dividing, and subdividing, in accordance with the \dews
of the cellular jiathologists. He was the first to prove the correctness of the
hypothesis of John Hunter that the cells, and consecpiently the tissues, in
inflammation return to a juvenile condition, in which the cells are enlarged,
become amoeboid and proliferate, while the " intercelhilar substance " is
liquefied and destroyed. That an emigi-ation of colorless blood-corpuscles
really takes place in inflammation is a granted fact.

Strieker was not aware that the basis-substance ("intercellular sub-
stance'') itself contains a large amount of living matter, and consequently
held that the inflammatory corpuscles are an offspring of the "coimeetive-
tissue cell" and its coarser offshoots only. Neither did he know that at fii'st

* " Stiulieii liber den Ban \\m\ das Lclicii der caitill. Itlutiiofassi'." Sitzungsber. d.
Wiener Akad. d. Wissensch, 1805.

t " Ueber Entziinduiig und Kitermif;." Vircliow'.s Aicldv, Hd. xl.

% "Studien aus deni Institute f. lOxneiiinciitelle Patliolosie in Wieu," 1870. And a
number of article.s of Strieker and lii.s jmpils in " Wiener Mediz. JalirbiicUer," 1871-1881.

356 IXFLAMMATION.

most of the iiiflainmatovy corpuscles remain united by delicate spoke-like ofT-
shoots, giving rise eventually to a new formation of tissue, consequently he
considered the intiiimmaiory corpuscles and the pus-corpuscles to be one and
the same thing, and inflammation and suppuration as identical processes.

In 1872,* when I took up the study of inflammation, in Strieker's labora-
tory in Vienna, I adhered to the cell theory, and my explanations of the phe-
nomena of inflammation were in accordance witli this theory. One year later,
however, I amiounced new discoveries concerning the structm*e of "proto-
plasm" and the basis-substance, and also concerning the intimate nature of
the inflammatory process. t The articles in this chapter on inflammation of
the connective tissue are translations of my papers which were published in
1872 and 1873 — the former being modified in accordance with the bioplas-
son views, the observed facts, however, and their description remaining unal-
tered. Instead of "protoplasm" I shall use the term "bioplasson." The
inflammation of the myxomatous variety of connective tissue is not dwelt
upon in the following articles. I refer to tlie article " Pulpitis," by Boedecker.

1. Inflajnimation of Connective Tissue.

fAJ InfldiiuiHifioii of the Periosteum. On artificially producing
inflammation in the bone of a mammal, — my experiments were
made on dogs, cats, and rabbits, — inflammation in the perios-
teum, in the neighborhood of the injured part, was also induced,
as a rule. The appearances are identical, whether the inflamma-
tion occurs in the calcified or in the non-calcified, the fibrous or
the ribboned periosteum. A specimen furnished by the perios-
teum of the scapula of a grown cat, on the third day of inflam-
mation, after having been preserved in a solution of chromic
acid, represented the features seen in Fig. 149.

We notice that, instead of the fibrous and ribboned structure
of the periosteum, a number of partly globular, partly fusiform,
elements are present, which are mostly nucleated, and grouped
in rhomboidal fields.

An analysis of the elements gives the following result : some
of them contain a, central lump of a bright yellowish color, either
homogeneous or pierced by vacuoles, and around it a pale, finely
granular zone. Other elements are found besides the homogeneous
lump ; these have but one pale nucleus, of varying size and glol)-
ular shape. In a vesicular nucleus of this kind we notice some-
times one larger and sometimes several smaller nucleoli. Lastly,

StmUen am Tvnoclu-ii u Kiinipel. "Wieiior Meiliz. Jalub., 1 ST'-'. I'eber.die Kiick-u Neiibil-
(liiiii? vou Blutgetiisseii iiii Knoclien u. Knorpel. Wiener Medi/.. .laliib., 187:^.

t "Untersuchuuf?en uber das I'lotoplasma. v. Die lOiitzundiiiifi: der Beiiiliavit, des
Knocheus iind des Kuoipel.s." Sitzinisisber. d. VVieiur Akad. d. Wissciiseli., .luli. 1S78.

/.V /••/.. 1. 1/1/. I 770.V

.'{57

we iiu'i't witli clciiu'iits in wliicli vvc <)l)S('rv(', instead of miclci,
toniiations, standiiiu' apai't, wliicli Iwivc cliaractciMstic^s of nucle-
oli. Between the i-lionil)oi(laI groups of the above-desoribed
elements we see narrow, fusiform ('ori)useles, ])erlia])s flat spin-
dles, seen on edgv. The interstices between the single <'lements
of all varieties produce narrow, light rims, all of which ai-e trav-
ersed by transverse, extremely delicate, grayish lines.

The })eriosteum hei-e is e\i(lently broken into elements, iden-

FiG. 149. — Periostitis of the Scapttla of a Grown Cat, Third Day of
Inflammation. Chromic Acid Specimen. [Published in 1,s73.]

-V, iiiick'iitcil plastid; i", solid liimi) of tlie aspect of aimclooliis; //-', iilastid with partly
iiomoircui'ous, partly reticular, formations, of the aspect of uucleoli; L\ vacuoled bioplasson
lump, surrouurteil by a bright rim of homogeneous bioplasson. Magnified 800 diameters.

tical with those which lay the foundation for the development of
the periosteal tissue.

All these features were still more prominent in specimens which
I obtained on the fifth day of inflammation from the periosteum
of a young, grown cat, after subcutaneous fracture of the leg
bones. In the inflamed periosteum, the elastic strips which di\dde
the tissue into rhomboidal ril)bons could be recognized. Some of

358

IN FLA MM A TION.

these ribbons are composed of rows of globular elements ; others
are broken up into a number of fusiform corpuscles, and again
others are in part made up of these corpuscles, while another
part retains tlie character of a periosteal 7'il)b<)n. The transition
of granular corpuscles into periosteal rhombs, which are infil-
trated with basis-substance, and look apparently homogeneous,
is nowhere al)rupt. The images of either variety may. to such

Fig. 150. — Periostitis of the Fractured Tibia of a Grown Cat.
Fifth Day of Inflammation. Chromic Acid Specimen. [Published
IN 1873.]

E, elastic strips ; PP, s^lobular ami nucleated plastids, sprung from ribbons of the ijeriosteum ;
R, transition of the basis-substance into free bioi)lass()n. Magnified 800 diameters.

an extent, merge into one another, that even a single rhomb may
appear in part pale and granular, and in part homogeneous, like
basis-substance. In this specimen the single protoplasmic cor-
puscles, without exception, also exhibit the features described
above. (See Fig. 150.)

At the point of the most intense inflaijimation, in the peri-
osteum under consideration, extensive fields are transfoi-med into

/.v/7. I.1/.1/.I 1 1 OS. .T)!)

iniiiu'rous ^lolmliir cli'iuciils, which Jii'c cspfciiilly crowded in the
vicinity of the l)h)od- vessels. In the parts situated between the
hlood-vcsscls <irou|)s of chMiiciits or sin^'lc corjmsch's sii'e found,
sun'ouudcd ])y ;i /one of hasis-siibstaiicc, which in the <']ironiie
acid spcciiiicn has a lioiiio^t'iicoiis a]>|)cai"anc(', and hears a (dose
resemhhincc to nofiuai meduUarv tissue, (ii'oups of iidhininia-
tory curpuscdes «;ive rise to a. cai'tiha^inous tissue. This fa(d can
he aseertained by observation of tlie foi-nniiii' calhis in tiie hder
days of the int1annnation.

In the eartihi.uinous calhis, wln(di is the offsprinj;' of tlie
intlanied jx'riosteum, we sonudiines see in a l)asis-su])stance, wlii(di
is usually striated, large, pale, nucleated bioplasson bodies. Fre-
quently we find smaller, yellowish, shining lumps, perforated
with vacuoles, and sonietiin(»s lumps composed of such yellow
granules. Finally, small cavities are observed in the l)asis-sub-
stance, whi(di contain but one snudl ])riglit-yeUowisli lump. (For
illustrations, see arti(de on " Healing Process of Fractured
Hones.")

The structure of this callus-tissue is in every particular iden-
tical with that of normal cartilage. The only difference is that
in the callus all corpus(des and their nuclei contain, at the points
of intersection of the reticulum of living matter, very shining,
yellowish granules, either single or in groups. These bodies
evidently represent the juvenile condition of the bioplasson. The
newly formed cartilage tissue is traversed by straight, glistening
fil)ers, which divide the tissue into rhomljoidal fields of varying
size. These elastic fibers belonged originally to the periosteal
tissue, and remained unaltered l)y the inflammatory process.
They are recognized as such even in calcified portions of the
cartilage ; they, without any apparent regularity, traverse both
the calcified basis-substance and the newly formed medullary
spaces. That the process of inflammation in periosteum can
])roduce not only medullary corpuscles and cartilage tissue, but
red blood-corpuscles also, I propose to demonstrate in the next
articles.

Since having inadt> th(> above observations, I have seen exactly the same
changes in the inflammation of tibrons connective tissue in the derma of the
skin, the pericementum of the tooth, and in many other localities (see
corresponding articles). The process was materially the same. First a dis-
.solution of the basis-substance took place, which led to a freeing and re-
appearance of the bioplasson, prevdously concealed in the basis-substance.
Next by an outgi'owth of single gi'anules of bioplasson new elements arose,

360

IX FLA MM A TION.

in an amount greatly exceeding the original number of plastids. At last,
after the inflammation had subsided, a new infiltration with basis-substanee
ensued, and consequently a new formation of connective tissue took place —
imless the inflamed tissue, from the condition of free bioplasson, immediately
fell back into the basis-substance-forming stage. Similar features are
observed in inflammation of the tendinous and peritendinous tissue of the
horse, termed by veterinary sm-geons " softening of tendons." (See Fig. 151.)
The original dense fibrous connective tissue, containing only a small number
of plastids, is gi-adually transformed into a more homogeneous basis-sub-
stance, in wiiieh niimerous plastids of var^dng sizes have made their appear-
ance. That these newly appearing plastids have not originated from former
plastids of the connective tissue, but arose independently after liquefaction
of the basis-substance at certain points, which at first were nearly regidarly

Pig. l.il. — Peritendinitis ix a Horse.

B. tibious basis-substauce with a few plastids ; ^^, the basis-subst.aiice more boniogeueous,
with uimuTous, uewly appeared, nucleated pla.stids; /, the basis-siibstaiu-e traiisfoiiued into
vows of nucleated plastids, or multiniiclear bioplassou mas.ses; A, artery, cut transversely,
containing a few blood-corpuscles. Magnified 800 diameters.

distributed throughout the basis-substauce, is plainly demonstrated by all
specimens of this kind. The whole basis-substance retm-ns to its bioplasson
condition — /. e., is transformed into rows of plastids or into multinuclear
bioplasson masses, before any new formation proper has taken place. It
may be easily understood how this slowly advancing inflammation, not going
beyond the stage of liquefaction of. the basis-substance and the retiu-n to the
bioplasson condition, might lead to a gradual "softening" of the tendon
tissue.

ixri.AMMATiox. :m

flij IufhiiiniKifioii of i'urfiliKji. After in-itatioii of (•artila<rc
tissue, tlu' action which ensues (lejjends ui»(>u the intensity and
dei»th of the injury, as well as ni»oii the hicality t<t which the
irintatinir a^^ent was appliecl. In ordei* to i-endei- the conditions
uniform in all experiments. I chose the articular cartilajre of the
condyles of the femurs of ehh)roformed dogs, cats, and rabbits,
whicli I injured with a red-hot pointed piece of iron.

Suptrfirid] IiiJHrirs in fin Middle of fJic C(»i(li/I(\ Twentv-s-lx
liours after the injury. I found the excavation produced by the
iron partly covered with au eschar, and the tissue in the ueigh-
l)orhood of a g^a,^^sh yellow color. A few cartilage cavities were
eidarged. and contained a finely granular, sometimes vacuoled,
mass.

In specimens ol>tained on the fifth day of inflammation of the
articular cartilage, I found, close to the border of the injiu'ed
place, large cavities, in part opeii toward the surface. sur})assing
in size the normal cartilage ca\dties sometimes by five diameters.
Between these enlarged cavities the basis-substance was reduced
to narrow septa. The ca\ities contained a pale granular sub-
stance, divided into fields and nucleated corpuscles. I was
unal>le to determine whether these had originated from a single
enlarged corpuscle, or by simple reduction of the basis-substance
between the original cartilage corpuscles. The latter view was
supported by the fact that sometimes several corj^uscles were seen
occuppng the larger cavities, surrounded T)y a narrowed basis-
.substauce. Close to the changed zone, around the injury, unaltered
cavities were observed, which held unchanged corpuscles.

The appearances were the same, after the inflammation had
lasted for eight days, in specimens taken from the knee-joint of
an old rabbit, in which, in consequence of the injury, suppura-
tion had occurred. The spindle-shape of some of the cartilage
corpuscles which lay close to the border of the wound could be
accounted for by the mechanical pressure of the iron rod used in
producing the inflammation. The result was such that in the
middle of the articular cartilage, even by the most intense irrita-
tion, only slight changes could be produced in the cartilage tissue.
These changes consisted in an enlargement of both the cartilage
corpuscles and their cavities, while a formation of pus-coqjuscles
could not be obtained.

One year afterward, the late Prof. Eokitanskj' kindly placed in my hands
the second right rib of a man about twenty-five years old, who, in a di-unken
brawl, had had the cartilage completely cut through six weeks before death.

362

TXFLAMMATTOX.

:^'^,

The woTind looked fresh, just as if produced but the day before ; even the
nist-spots from the knife were still ^-isible. The perichondrium was thick-
ened and held the two severed ends of the rib cartilage. Microscopic exami-
nation showed enlargement of some of the corpuscles close to the edge of the
woiuid, but no other pathological changes.

Simultaneous Injuries of the Articular Cartilage and the Suh-
jaccnt Epiphifseal Bone. Upon boring a hole into the cartilafre. and
penetrating the hone with the red-hot iron, a very striking phe-
nomenon occurred — namely, a deposition of lime-salts in the car-
tilage, around the seat of injury. This feature, which was known
to Redfern,* could be demonstrated after twenty-six hom-s, and
recognized by the naked eye on the third day. The deposition of
lime-salts was broadest at the border of the bone, and gi'adually
became narrower toward the surface.

Close examination revealed the lime-salts deposited in the
basi.s-substance of the cartilage, and in this situation most of the

coi-puseles had assumed an irregidar.
jagged appearance, due to oif shoots
arranged after the manner of a deli-
cate net-work. At the boundary of
the calcification, I met with cartilage
ca\dties, surrounded either by un-
changed basis-substance or by a cal-
cified ring, which, as a rule, broadened
toward the fields of general calcifica-
tion, and was separated from these
fields by coarsely granular depositions
of lime-salts. (See Fig. 152.)

After decalcification of such speci-
mens, it was apparent that the corpus-
cles next to the border of calcification
had become, either in part or wholly,
transformed into homogeneous or
vaciioled, yelloAnsh. shining lumps —
\'iz. : had returned to a juvenile stage.
Beginning from the third day of
inflammation in the calcified portion,
spaces were found, which were larger and more numerous nearer
the bone than in other localities. These medullary spaces invari-
ably started from the portion adjacent to the bone-tissue. The
basis-substance being liquefied, the newly appearing corpuscles

H.^/.

Fig

l.">2. — Calcified Carti-
lage OF A Middle-sized
Rabbit, after a Simul-
taneous Injury of the
Articular Carth^age and
the Bone. [Published in
1873.]

P, blight, yellowish cartilage cor-
jjiiscles, traverseil by vacuoles ; B,
non-calcified basi.s-substance, with
ladiating offshoots of the cartilage
coipuscles ; (', calcified basis-sub-
stance at the boundaries of the teiTi-
tories. Magnified 800 diameters.

Anormal Nutrition in the Ai-ticular Cartilages," London, ISoO.

/.v /-v.. 1.1/1/. 1 7/o.v. :U):{

had cither assiuiu'd a sj)iii(U(' shajx- ov were fust'd into niH'lt'atfd
hiophissoii inassi's, with a simultaiuMms prodiu'tioii n\' hlood-
('»»r|ms('h's and bhtod-vcssds in the iiiiddh' of tlic iiicdidhiiv space.
C'h)sc to the l)order of these spaces the cor]:)Usclcs exhibited no
other changes than those above described. The epiphyseal bone,
by dissobition of its basis-snbstance and im-rease of the eorpns-
(des, also api)eai"iMl to be i)rovided with medullary spaces, and
the perforation made l)y the iron was, after several days' inflam-
mation, filled with nucleated masses and fusiform elements.

These experiments prove that a simultaneous injury of the
cartilajie and the bone is followed l)y a calcification of the car-
tilajife along the border of the wound, and afterward by a dis-
solution of the calcified basis-substance, commencing in the
vicinity of the l)one and advancing toward the articular surface.
The freed bioplasson behaves in a manner similai- to that of
inflamed bone.

Injurifn at th<' LaferaJ Forfions of the Aiiinihir Cdrt'ddijc.
The nearer the lateral edge of the articular cartilage the hot
iron was applied, the more intense were the changes in the endo-
thelium, in the syno\'ial membrane, in the fibrous cartilage, and
in the neighboring periosteum and tendons.

At the edge of the condyle of a young cat, on the second day
after the injury, the tissues covering the cartilage were thick-
ened and rendered cloudy by a considerable infiltration with
inflammatory corpuscles. The tissue of the syno\'ial membrane
and the periosteum exhil)ited groups of corpuscles, which in
some places were so crowded that only slight remnants of the
fibre ms bundles were visible.

In specimens of a young rabbit, from the sixth day of inflam-
mation, the surface of the cartilage was covered with a contin-
uous, freely nucleated layer of bioplasson, which was not sharply
marked from the subjacent cartilage tissue. The ca\'ity of the
wound of the cartilage was found to contain along its borders
numerous tracts of corpuscles, closely packed together, and
uniting with analogous tracts proceeding from the subjacent
bone. (See Fig. 15H.)

Upon examining hyaline cartilage at points where it passed
into the fibrous variety, and into periosteum, I recognized large
ca\dties filled with corj)uscles. containing large nuclei, often so
closely arranged that the l)ouudaries between the corpuscles
could not be distinguished. Similar formations were foimd also
at the border of the scapula of a young dog, on the fifth day

364

IXFLAMMATIOX.

after the injui-v. Itut only in that jxntioii of the cartilage lying
nearest the osseous Vjorder.

With an augmentation of the eorpuseles. a retrogression of
the bioplasson to the juvenile condition takes place. As red
lilood-coi'puscles are formed out of this bioplasson sulistance,
I have termed it '' ha^matoblastie." This rejuvenescence and
transformation into red l>lood-coi'j)uscles occurs in the inflam-
matory process, not only in cartilage corjjuseles, but also in the
corpuscles of synovial membrane, periosteum, and tendon. (See
Fig. 154.)

6 i *■■ |,'«f<s'/.'7' ,

^^Sr:-

IB

I K

:f

/

MS

Fig. 1. is.— Condyle of Femi-r of ax Old Rabbit, on the Eighth Day
OF Inflammation, Produced by Injury at the Lateral Surface.
[Published in 1873.]

EC, iinclianged cartilage ; IX, large medullary si)ace in place of the fomierlj- calcified c;ar-
tilage; 7", unchangeil trabeculaof Ijone; IB, medullary space in the bone-tissue, penetrating
tlie calcified cartilage : MS, iuicUange<l vascular canal. Magnified 200 diameters.

Feeding of Cdtiilage-corpuscles irifJi Iiisoh<hJe, Gravular k'^uh-
sfances. I have injured with the red-hot iron the middle portion
of the articular cartilage of the condyle of the femur, and that
of the tibia of a young, nearly grown dog, and killed the animal
seven days afterward. Around the jagge<l border of the wound.

ISFI.AMMA I lOS

lUi.")

ill !i zone ;ilM»ut two iiiilliiiictci-s wiWc, I could sec with the naked
eye an intense brown discoloi-ation of the cai-tilajrc. A similar
discoloration was present on tlie tibia, tlion<i:li )nuch less marked.
Jn hoi-i/ontal sections from the condyle of the femnr I found
the l>asis-su})stan(H' of the eartilage ealcified around the wound,
and the ealeified zone broacU'iied from the surfaee toward the
bone. The ealeified basis-substanee appeared to be divided into

vf^H'^E^M^f^r-,.

I'hK

Hr

TT

/',-;

I

;^1

'/

Fig. ir)4. — Lateral Surface of the Condyle of the Femur op a
Grown Cat, on the Seventh Day of Inflajimation. Fresh Speci-
men. [Published in 1872.]

JI, li3-alinc' cartilage m transition to F, libious cartilage: '', greatly widcjied cavity, tillcU
with iuHamniatory conniscles; JB, newly formed red blood-corpuscles, siirnng from L, tlie
bioplassou in a juvenile condition. Magnified 800 di.imeters.

glistening, polyhedral fields of a ])rown color. Avhieh was more
intense and wide-spread on the surfaee of the cartilage. Many
of the cartilage corpuscles within the brown basis-sul (stance

366 IN FLA MM A TIOX.

contained granules and lumps of a blackish-brown color, which
were most numerous at a certain distance away from the border
of the wcniud. Extremely minute l>lack jjfrauules also were found
in the basis-substance. That these granides were animal char-
coal could easily be determined bj^ comparing them \vith the
charred pastids attached to the surface of the wound, and with
the eschar of the cartilage of other animals. But how did the
charred granules penetrate the cartilage corpuscles f There must
have been either a carbonification of certain parts of the cor-
puscle and the basis-snbstance, or else the coal particles had
been transported from the surface of the wound toward the
periphery.

The supposition of a partial carbonification was not sustained
by experiments on other animals, — cats and rabbits, — and I
never succeeded in producing brown granules in the corpuscles
situated in the neighborhood of the burnt place of live or dead
cartilage. The conclusion, therefore, became admissible that the
coal particles realhj were transmitted within th<' hasis-sHhsfaiice hi/
an acti re process of the cartilage corpuscles and their offshoots.

Other expei'iments with powdered vegetable carbon and cin-
nabar, forced into fresh wounds of the cartilage, did not yield
satisfactory results. I succeeded but once in demonstrating the
presence of cinnabar granules in a cartilage corpuscle inclosed
l'»y an uninjured basis-substance. Cinnabar granules, on the
contrary, which I had injected into the jugular vein, I invariably
succeeded in finding in the cartilage corpuscles, within the dis-
trict of inflammation, bt)th in inflammatory corpuscles, filling the
enlarged cartilage cavities, and also in cartilage corpuscles,
apparently unchanged. I can, therefore, corroborate the asser-
tions made bv Reitz and Hutob.

In inflamed cartilage I have often seen red blood-eorpuscles arising from
both the corpuscles of cartilage and medulla. The insular and intravascular
fonnation of red blood-eorpuscles in some cases proved to be extremely
active. After injuries inflicted on the lateral surface of the condyles, I
observed enlarged fusiform cavities, which evidently had sprung from carti-
lage, partly or totally filled with initial forms of red blood-eorpuscles — the
" hiemotoblasts " — as well as with fully developed corpiiscles. Solid bioplas-
son tracts sometimes dii-ectly connected the closed caAnties of the above
description, which were found in a large number, especially toward the ten-
don-tissue ; they were sometimes hollow, and contained a single chain of red
blood-corpuscles. The process of new formation of l)lood-vessels and blood
proved to be identical with that noticed in inflamed bone-tissue, and for fur-
ther particulars I refer to the article on inflammation of bone.

IMLAMMATKLW 'Mu

fCJ IiiJhinntKit'hnt of liom: Xiiiiici'ous cxpcriuiciits iiiJidc
(liirin<i' the ycai's 1S7"-I mikI IST^J, on Itoncs of (l(»^s, (^ats, {lud nil»-
bits, for the j)uri)ost' of artificially producing inflanimation,
cnablfd nic to obtain a j»vn('ral view of the phenomena of oste-
itis, ffoni its incipient stag-e np to the eighth day. These are:
first, the freeing of the l)ioi)lasson from its l)asis-snbstance ; and,
secondly, the return of the ]>io})lasson to the juvenile condition.

In the earliest stages of the inflammation, twenty-six hours
after the injury, also in the succeeding days, at the periphery of
the inflamed district, a dissohifion of the I'niic-sdlts of fJie htisis-
siihsttiiirc tdhi's pUirc in Ixifi-liki' fields ; this destructive process,
however, does uot invariably invade the whole of the territory,
l)ut often only part.

Tlir decah-ified hasis-sKhstance itself is next dissolved out, and in
its place Jinf or r/Johnlar hioplasson masses hecome visible, either
single or coalesced into groups, exhil)iting a number of nuclei,
each of which corresponds to an original nucleus of a bone-cor-
puscle. Within these coalesced groups, new nuclei originate, and
the multinuclear body presents the appearance formerly known
under the name of a "myeloplax." (See Fig. 155.)

Such multinuclear bioplasson masses arise from one or sev-
eral coalesced bone territories, and represent the bioplasson of
the territory itself.*

A midtinviclear body, at the periphery of the inflammatory
district, may at once lay the foundation for the new formation of
a bone territory ; or it may, in the more central portions of the
inflanmiatory district, di\'ide into a number of corpuscles, each
one of which is provided with a nucleus. The corpuscles, as well
as the larger bioplasson layers, are separated from the neighbor-
ing kindred formations by light, narrow rims, which are trav-
ersed by transverse filaments. These filamentous formations
are thi-eads of living matter, by which all newly developed ele-
ments are connected with each other and also with neighboring
bone-corpuscles not yet set free.

This series of changes may be observed in the middle of
the bone-tissue, as well as at the borders of vascular canals. The
dissolution of the decalcified basis-substance, as a rvde, begins at

* The multiuuolear bodies are by no means formations confined exclusively
to the medullary tissue of bone. They may appear wherever ten'itories
(units) existed before the infiltration with basis-substance took place, or
where the basis-substance, either in normal or in morbid processes, is slowly
being dissolved out, and thus the units of the tissue made free.

368

INFLAMMA TION.

the border of the lacuna, therefore in the circmnference of the
uniufiltrated bioplasson body, — the bone-corpuscle, — and ad-
vances outward toward the periphery of the territory. We can
satisfy ourselves that it is not the ccntrdl hoHc-coypiisch' itself (ilouc
irhicli ciiJatyes, tiitt that, after a ivastiiaj or disso/iitiou of tJie Ijasis-
siiljsfaiire has talen place, leadinf/ to thefreeiinj of the l)ioplassoti.

SF^'M

' ;i III.

7 "

K''^!,!

■sYflm

ji

|iiiifn?Tf#-*

r I

Fio. 155. — Bay-like Excavatioxs, Produced by Dissolution of the
Basis-substance, from the Tibia of a Do(i Injured with Red-hot
Iron; Eighth Day of Inflammation. Chromic Acid Specimen.
[Published in 1872.]

Ji, xiiicliansfd boiio-tissiii', with C, tlie boiie-coipusclca ; 7', large nucleated bioplassoii
inassos, tilling the hays in tonnection with the luichangt-d hone, by ineaiia of delicate flla-
incuts. Magnified SOO diaiiieter.-s.

the latter, which hefore the inflamniatioH iras seen only in the hone-
corpuscle, hecomes visible throughout the whole territory. The
next step in these phenomena is that the bi<)])lassoii contained in

IM'LAMMATIOX. ;{()<J

tlu' former ossoons l^asis-substniioc now divides into a nuniher
<tt' Hat. fusifonii. nuclcatt'd bodies. As a matter of eourse, it is
the reticidar l)ioi)lasson witliin the basis-snhstanee, and not the
l)asis-substan<'e itself, furnisliin«i- the material for these elements,
which are not really newly formed bodies, bnt only made visil)le
and re-arran<;ed in new <;Ton)»in<>'s.

The linal resnlt of the melting or dissolution of the basis-sub-
stance is the appearance of medullary spaces. They may arise
from bone-eorpuscles and their surroundinji' basis-substance, in-
dependently of the vascidar canals in tlie middle of the bone-tis-
sue. This fact was known previously by Rokitansky. Medullary
spaces may also have their origin in the borders of vascular
canals, and the nearer the wound of the l)one, the larger and
the more irregularly excavated are the medullary spaces come
from the vascular canals. They are always packed vnt\i globular
or spindle-shaped c<n'puscles, while in their centers blood-vessels,
<M)ntaining l^lood-corpuscles, are found.

Running from the widened vascular canals, now transformed
into medullary spaces, are channels filled with medullary corpus-
cles, which penetrate the interstices between the systems of
lamella\ The spaces which arise in the vicinity of the bone-cor-
puscles unite with those of the widened vascular canals and
interstices; and in intense inflammation, up to the eighth day,
the formerly compact bone is transformed into a cancellous
structure — /. e., only narrow trabecular of unchanged l)one are
left, between which are large spaces containing medullary cor-
puscles. In still more intense inflammation, especially that pro-
duced l)y l)oring into the compact l)one with a i)ointed hot iron,
the l)one-tissue in the district of inflammation around the wound
is to a great extent transformed into medullary tissue, hoi ding-
newly formed blood-vessels, and in this tissue, only very small,
irregular islands of the former compact bone are found. Obvi-
(msly, the juvenile condition of the bone is reestablished by this
process, even in its coarser anatomical relations. (See Fig. 156.)

The elements which have newly appeared bear a close resem-
1 )lance, so far as theii- shapes are concerned, to those present in
normal vascular canals, between the wall of the blood-vessel and
the wall of bone. They are nothing more than medullary ele-
ments in the stage of indifference — eventually osteoblasts.

In slight degrees of iuflammation, the medullary elements, \\\)
to the eighth day, may, at the surface of the inflamed bone, again
be transformed into the so-called '"osteoid" tissue bv infiltration
24

370

IXFLAM.^fAlIOX.

with lime-salts. In this way are originated new trabeciila?, with
a high degree of luster, between which, in irregularly aiTanged
caWties, in part nucleated bioplasson bodies are left. In the
recalcified basis-substance we can trace the former mcduUary
corpuscles, as their general configuratiou is unaltered. The
reticular structure of this basis-substance is distinctly visible
without any re-agent, owing to the high degree of refraction of
the fields, infiltrated with lime-salts. (See Fig. 157.)

The second series of changes concerns the bioplasson itself :
// I'lfu}')}.^ in ft i-fhiflrfh/ short time from flip phase of ndranced

<;t

jf '-'^'

Fig. 1.56. — Traxsfor>iation of Compact Boxe into Medullary Tissue.
Tibia of a Dog, Eighth Day of Inflammation. Chromic Acid
Specimen.

7f, wideneil Ilavcrsiau caual; C, luojectjous of the compact bone, with considerably
eularged and apiuiieiitly auirmented bone-corimscles; /, islands of bone: J/, medullary tissue
containing newly formed blood-vessels. Majmitied 300 diameters.

development into the jnrenile roiidition. This occurs before any
other change, and is quite constantly observed in the homogene-
ous nucleus of plastids in the younger, and the nucleolus of
those in older animals. The nucleus is transformed into a bright,
yellowish body, which divides into several lumps. In the in-
flamed district, beginning fi'om the second and third day of
inflammation, we meet with bone-corpuscles, containing divided
uTiclei, even in unchanged osseous lamellae.

I Sh LAMM A I lOS.

M\

^fe

Hcjuvciieseenoe may iuv(>lv(' t'ithcr the laif^cr portion of
})(nie-(M)rjms('k's or the whole <'orj)iisck', and these ))odies are
jjartially or t(»tally ti-ansfoi-ined into yellowisli, sliijiin^ lnin])S,
which 1 formerly considered luematoblastie (see page 101). The
dissoluticm of the basis-substance around the homogeneous luni])
takes j»la('e in the same manner, as described al)ove.

TJu' nturti to fJir jiiriiiilt' r(Hi(lifi<>ii^ liotrrrcr, ntdi/ 'if (t roiit-
pdnitii'ch/ forh/ ihitt' iiiniflr iiof otdif the mifrti/ hoiit'-ror/jKsrIi\ Inif
also f<d(' phire, to o (p-cutir or less ^ ^^ ,

extent, in the l)toplasson. inclosed in ^^'^p^I.^v^^^^^'^^''?'^
the Ixfsis-snhstdnce. Some offshoots
of the bone-corpusele may become
broader ; in some of them even
rejuvenescence may occur, inde-
pendently of the central bioplas-
son body. Lastly, this change
may affect the whole mass of bio-
plasson present in a territory, as
illustrated by Fig. 40, page 126.
Here the retrogressive change in
the bioplasson preceded the disso-
lution of the basis-substance.

The result of the recurrence to
the juvenile stage of development
is different, according to its degree.
A number of bright, homogeneous
lumps may arise from the bioplas-
son of the bone-corpuscle, as well
as from that of the basis-substance,
and each lump, even the most mi-
nute, is enabled to produce a new
element. This new formation,
traceable step by step in the me-
dullary spaces, is due to the differentiation of compact bioplasson
into a reticulum, therefore an advance toward a higher stage.
Each lump, or each element, under these circumstances, remains,
by means of delicate filaments, in living connection with all its
neighbors. (See Fig. 158.)

Should the division of young bioplasson into small lumps
occur at a very early stage, and very rapidly, the formations
which I have termed " haematoblasts " will be the result. Each
hjpmatoblast, by being severed from the neighboring elements.

^^^^WI

Fig. 1.")7. — Recalcif - ; of
THE Medullary Tissue of a
Dog's Tibia, Injured with
Red-hot Iron, Eighth Day
op Inflammation. Chromic
Acid Specimen. [Published
in 1873.]

P, large, nucleated bioplasson iKulies :
B, calcified basis-substani-e. exhibiting a
distinct reticular stmctmi-. Magnified
800 diameters.

372

INFLAMMA TION.

and ])eeoming dense at its periphery, may give rise to a colored
blood-eorpuscle. The newly formed l)lood-corpnscles either lie
within and between other l)i()])lasson })()dies, or else they are
inclosed by a shell of bio])lasson which, l)v vaeuolation, has

iaMS

Fig. 158. — Fractured Fibula of a Grown Dog, Longitudinal Sec-
tion. Fourth Day of Inflammation. Chromic Acid Specimen.
[Published in 1873.]

T, Hat bioplasson bodies, in the stage of inilitfereiicc, bleudiiif; witli tlio basis-substance ; jp,
bioplassou bodies (inednllaiy corpuscles), spiuufr fioni botli tbe bone-corpuscle and tlie basis-
substance ; S, bioplasson bodies, witli numerous brijiht lumps ; A", original bone-corpnacle,
witli enlarged nucleolus, and a i)artly soliditied nucleus. JIagnitied SOO diameters.

become hollow. This represents the first trace of blood-vessels
which, from their earliest stag-e, hold red T)lood-corpnscles.

The second series of changes in inflamed l)(>ue, described

isri.AMMA ri().\. :{7:-5

above, lead to foniiatioiis, constaiitly iiii't witli in tlie iinnicdiatt'
viciiiitv of tlie iiiHanimatorv district. A ihhiiImt of newly
formed medullary spaces are filled with yellowish, shining ele-
ments, which, in their form and the nature of the l)Msis-su>)stance
surrounding' them, are analogous to normal juvenile nu'dullary
corpuscles. In such spaces a more or less a})undant new forma-
tion of red blooil-corpuseles, and also, though not eonstantly, of
Itlood- vessels, is going on ; the spaces, as a rule, contain in their
centers l)lood-cor])nscles and blood-vessels, and at their p('rij)hery
t)ioplasson l)odies of varying size. Sonu'tinu'S i-ed l)lood-cor-
puscles originate in multinuclear bioplasson masses, as I de-
scribed in 1872.

Finally, I emphasize that f/ir liriiu/ roiiHerfioii of the hiop/assoji
bodies, except the hfcmafoblasts, is not interrupted in the non-puru-
lent inflamniation of hone. An isolation am he asserted to exist only
in colored hlood-corpuscles and in pus-corpuscles. The blood-cor-
])uscles tioat in a lic^uid whose origin is connected with a partial
paling and waste of bioplasson. The formation of this liquid,
always occurs within the first vacuoles — i. e., the first vascular
tubes, and T)otli the li([uid and the newly formed red blood-eor-
puscles take part in the circidation as soon as the newly formed
vessels join the older ones. It has been proved by Rustizky * that
from the freed bioplasson in the process of inflammation of lione,
pus-corpuscles also originate.

N'ew Formation of Blood-vessels in Infianied Bone-tissue.f In
bone in which inflammation is artificially induced, a very active
new formation of blood-vessels takes place.f These are mostly
capillaries arising from the elements of the decalcified, l)ut not
dissolved, bone-tissue, and in medullary spaces originating from
the derivations of the bone-tissue — viz., the medullary corpuscles.

* " Untersuchungen iiber KiioclitMieitening." Wiener Meiliz. Jalirbiicher,
1871.

t " Ueber die Riick- ii. Neubildung von Blutgelassen ini Knoehen u.
Knorpel." Wiener Mediz. Jahrbueher, 1873.

t R. Volkmann (Langenbeck's Archiv f. Klinisclie Chiriu-gie, IV, Bd.
18 03) describes a new formation of vascular canals in the compact substance
of bone, occurring in so-called " vascular ostitis." WTiat this author describes
is not identical with what I have seen, for he maintains that in the formation
of vascular canals the bone-corpuscles take only an accidental part, or do not
participate in the least. How tlie vessels themselves are formed he does not say.

H. Lossen (Virchow's Ai-chiv, Bd. Iv., 1872) attempts to demonstrate, in
specimens obtained from dry bone, that the canalization of bone-tissue
really starts fi'om bone-corpuscles.

374

IXFLAMMATIOX.

At the surface of the injured scapula of a dog, on the fourth
day of inflammatiou, I met ^^'ith well-marked features indicative
of a new formation of blood-corpuscles and blood-vessels. (See
Fig. 159.)

I saw enlarged ca\'ities in the basis-substance, deprived of
lime-salts, containing a number of bright, yellowish, homogene-
ous lumps and disks, which might be properly termed " haemato-
blasts" (see page 100). Some of these lumps were vacuoled,

Fig. 159.— Scapcla Plate of a Dog, ox the Fourth Day of Inflam-
mation. Chromic Acid Specimen. [Published in 1873.]

L, lamps of bioplasson in a cavity partly inclosed by an investmi-nt of bioplassou : V, elon-
gated and vacuoled bioplasson tube, traversed by septa and containing isolated lumps —
the hamatoblasts : B^ and B^. offsboots of the bioplasson tube, terminating blindly. Mag-
nified SOO diameters.

others vacuoled and elongated, and, again, others considerably
enlarged by vacuolation. In all cavities produced by vacuolation,
isolated haematoblasts in varying numbers could be seen beside
a pale gi*anular mass. By coalescence of vacuoled bioplasson
bodies tubular formations originated, which were di^dded into a

IMLAMMA ilOS.

375

numhrr of cliamlKTs 1)V triiiisvcrs.- or ()hli(|U(' s('])ta, tlu- ivninaiits
of thf h..llow<'<l b.ulics. The septa cvciitually (lisai)iM>ariii^^ by
Uquefactiou and wasting' of the bioplassou, a eoninioi. cahber is
established, iiTe<iidarly bounded
by flattened hiyers of nnehaniivd
biophisson, exhibiting- in their
optical diameter a number of
nodulations. This tube is in a
direct eoniniunieation with hol-
low offshoots, exhibiting- the
same features, and terminating*^
either blindly or in cavities de-
stitute of a bounding- layer, but
containing haematoblasts.

In the scapula plate of a cat,
on the thii-d day of the artifi-
cially induced inflammation, I
observed solid bioplasson tracts,
which arose from the liorder of
a medullary space, ran along the
lamelhp, and connected several
enlarged and homogeneous bone-
corpuscles. Not infre(iuently the
bone-corpuscle next to the me-
dullary space was most enlarged,
and appeared hollow, while the
distant corpuscles of the chain
were solid. I also observed fin-
ished tubules, terminating in a
solid point and traversed by
transverse septa or their rem-
nants, indicative of the origin of
the tubule. Such tubules always
contained a varpng number of
isolated solid bioplasson lumps,
the " haematoblasts, " — to-
gether wnth finely granular,
coagulated albumen. (See Fig.

160.)

In many specimens obtained from inflamed bone, up to the
fifth dav of inflamnuition, I observed similar formations in the
newly formed meduUary spaces also. In all cases, first, solid

Fig. 160.— Scapula Plate of a
Cat, on the Third Day op In-
flammation. Chromic Acid
Specimen. [Published in

187:^.]

Newly foniijng blood-vessel, tenuiuatiuK
in a vacuoled plastul, L : .S, reiuuant of a
former septum ; Jf, himps of bioplasson —
the luematoblasts— entangled in tinely
granular, coagulated albumen. Ma.!?nitit'»l
800 diameters.

376 IX FLA MM A HON.

bioplasson tracts were seen, which, l)y vacuohitioii, be(;aiiie hol-
lowed, often exhibiting: transverse septa, — the remnants of the
walls of the vacuoles, — and containing ha^niatoblasts. From the
walls of these forming blood-vessels, solid buds or fusiform or
club-shaped prolongations arose, which indicated the formation
of new, collateral branches of blood-vessels. Not all the red
blood-corpuscles found in medullary spaces were inclosed in
blood-vessels, for I often met with blood-corpuscles, isolated or in
groups, among the medullary elements which had sprung from
inflamed bone-tissue, without a trace of an investing l)ioplasson
layer. Such corpuscles evidently are never carried into the circu-
lation, and I was unable to discover either their office or destiny.

Often, multinuclear bioplasson masses were found, holding in
their substance a varying number of red blood-corpuscles. Sev-
eral times I observed an outer investment of spindle-shaped bod-
ies, which surrounded the multinuclear masses. Sometimes the
spindle-shaped bodies produced a well-marked, broad layer
around these masses, which had been partly changed into a homo-
geneous or finely granular, possibly liquid, substance. Along
the investing layer, inside the caliber, wreaths of haematoblasts
were seen. All these features indicated the formation of veins ;
but I was not able to determine that the investing spindles were
muscle formations.

That in inflamed tissues a new formation of arteries occurs I
am certain from a specimen of Prof. Strieker's, who, in 1871,
showed me an inflamed cornea — I cannot recall whether of a
frog or a rabbit — in which a newly formed artery could be posi-
tively diagnosticated.

Conclusions arrived at in 1873. Inflammation was considered
by humoral pathologists to consist essentially in a diseased con-
dition of the blood and an exudation of its plasma ; while cell-
ular pathologists located the disease predominantly in the
'^ individuals," the "tissue-cells." The latter view, announced
by Virchow, was the leading one up to our time.

The presence of an exudation, the altered liquid of the blood,
in the inflammatory process, needs to-day no special proof. It
has never been doubted. The phenomena in the inflammation
of bone could not be explained without the presence of a liquid
which causes a dissolution first of the lime-salts and afterward of
the glue-yielding basis-substance. Inflamed cartilage tissue like-
wise furnishes important proofs of the presence of an exudation.
The fact that injuries entirely confined to hyaline cartilage pro-

rxri.AMMA 11 OS. ;{77

<lu('t' triHint"- clmiiucs, while, if cai'tila^'c and l)one be injured
simultaneously, very marked ehany,('s (XM-ur at ouee in the ear-
tihij;e tissue, indicates a direct dependence of inflammatory
ehanii-es on l)lood- vessels. Tlie rapid deposition of linu'-salts in
tlie latter ease can scarcely take place from any other source
than fi-om a li(iuid introduced into the cartilage corpuscles.
Upon boring: into the cartilage and the bone, lime-salts are
deposited in the basis-substance of the cartilage, at the border
of the perforation, in a zone Avhich broadens as it ai)proa('.hes
the bone. This proves that the aperture is inundated with a
liquid, flowing from the blood-vessels of the injured bone, from
which the living nuitter of the cartilage derives the lime, origi-
nally kept in solution, ultimately to be deposited in the chondro-
genons basis-substance.

Neither the sum of facts so far known to occur in inflamma-
tion of cartilage, nor the observations in keratitis, furnish any
foundatioii for overthrowing the theory of exudation, and of the
participation of the blood and the blood-vessels in the inflamma-
tory process.

As regards the changes of the assumed " individuals," the
" cells," this is a different matter.

Strieker was the first who positively declared that the cells
by inflammation are reduced to a juvenile condition, in which
they are enal)led to proliferate. This assertion was based upon
the observation of the changes Avhich take place in the " proto-
plasmic body'' — namely, its swelling, its becoming amoeboid, the
formation of new nuclei and new corpuscles from the older ones,
and also the wasting of the '' intercellular substance."

This view, with all that it involves, can be maintained, not
only so far as the cells are concerned, but also for the inflamed
tissue in general. Eceri/ tissue, hi/ the injhimmdtory process, is
reduced to the condition in which if existed in the first stage of its
development — that is to sdi/, to <i condition corresponding to its
emhri/onal state.

Thus bone-tissue, in inflammation, is dissolved into the ele-
ments from which it originated. Through the dissolution of the
basis-substance medullary spaces are formed in the bone, at cer-
tain distances, which give to the inflamed bone of an animal, no
matter how old, the appearances found in a newly born individ-
ual. In addition to this, in inflammation the basis-substance
loses its lamellated structure, and in part assumes a striated
aspect, which again corresponds to the bone of a new-born

378 [NFL A MM A TION.

animal. Finally, the medullary spaces are filled with elements
identical to those from which bone-tissue orig'inated.

The same is the case with periosteum and cartilage. The
periosteal ribbons, whose boundaries remain marked by un-
changed ^' elastic ftbei-s," are dissolved and form rows and groups
of globular and fusiform corpuscles, which correspond with the
original formers of periosteum, not only as regards their shape,
but in eveiy particular. By inflammation cartilage is transformed
into medullary elements, such as originally composed its tissue.

The totality of the elements observed in the inflammatory
process has been designated by the terms '' inflammatory new
formation,'' " granulation tissue," and '' suppuration." Recently,
every newly appealing element was termed simply a ''pus-cor-
puscle."

My own observations prove that the netdy appearing elements
at first are nothing but the elements of the tissue themselves.
The term ''inflammatory new formation" is applicable only in
the later stages of the inflammation, when really newlij produced
corpuscles have originated from the freed mass of living matter.

The designation " granulation tissue " is scarcely tenable for
the earliest stages of the inflammation, inasmuch as there is no
new tissue produced, but only a formation analogous to that
from which the inflamed tissue sprang — that is, a medullary
tissue-formation for periosteum, cartilage, and bone.

The general designation of " inflammatory new formation,"
applied to "suppuration" or "formation of pus-corpuscles," is
decidedly incorrect. The resrdts of my researches show that the
newly appearing, as well as the newly formed, elements are con-
nected uninterruptedly l)y filaments of living matter, both with
each other and with the non-inflamed neigh l)oring tissue.

If in inflammation of a tissue single corpuscles become sepa-
rated from their neighbors, and the so-called " migrating cells" are
produced, their locomotion is evidently only a transient action.
The newly formed red blood-corpuscles lying within their newly
formed vessels, and which in a later stage join the older vessels,
are really separated from the parent soil.

PHS-co)pnseIes, on the contrary, are uncpiestionably isolated
elements which are separated from each other by a liquid. Pus,
however, is no tissue, and from it, so far as we know and it is
generally admitted, new tissue will never arise.

There is a marked difference, therefore, between those proc-
esses which pathologists have termed "plastic inflammation,'' on

/.v /•'/.. I.U.I/. I riox. :57'.»

the one liaiul, luul '• .v^?y;/>/ov^///7' injl(ittini((fi()ii" (>\i the otlici-; iil-
tliouii;!! it may be ^ruutctl tliat these processes depend only on
ditferent de'!:rees of irritation.

Let us consider the infhiiiiniatory (•han<:;es of tlie Jirliu/ timffcr
of the tissue-units. In iuHMiiiiuation, this niattei" is prol)ably at
tirst jn'ovided witii a siir))lus of li((uid nourishiuii' material. The
(luestion whether this material is eonveyed in si)aces between the
livinii' matter and the ])asis-substanee. or wln'thei' the li(piid im-
mediately enters the living? matter, — /. p., is imbibed by it — cannot
be answered by direct ol^servation. This fact, nevertheless, is
certain, that the surplus nourishinjif liquid shows its effects gen-
erally in the youngvst portion of the tissue-unit — viz.: in the
nucU'ohts and the nucleus of the non-infiltrated corpuscle. This
portion is usually the first to return to the juvenile condition;
it is divided into a number of particles, as has been stated by
Virchow.

The livinj>' matter inclosed in the l)asis substance, upon
recei\'iny the increased noui-ishing- material, resj)onds, as a nde,
by a dissolution of its basis-sul)stance. Next follows the reestab-
lishment of the juvenile condition in a certain number of centers,
each of which represents a nucleus or a nucleolus ; and thus the
embryonal or juvenile stage of the tissue, as described above, is
re-assumed. Nearer the intlamnuitory focus the recurrence of
youth is established in a larger amount of living matter, which is
transformed into compact masses. Each mass may divide, and
each fraction may give rise to a new corpuscle. If the connec-
tion between these corpuscles remains intact, medullary tissue is
the result ; if, on the contrary, the connection is broken, the com-
pact i)articles of living matter are iHeuuifoJihists^ and, eventually,
red blood-corpuscles.

The formation of new elements from larger masses of living
matter, as can be directly proved, is accomplished in such a way
that within these masses, at certain intervals, new boundaries
arise, the so-called ** nuirks of division," which depend upon the
location of the compact centers. These boundaries are newly
formed cement- or basis-substance, in which there are no reticular
formations, but merely delicate spokes of living matter. Every
newly formed inflammatory coi-puscle corresponds to a central
body, whose living matter retains its embryonal condition —
viz. : to a nucleus or to several nucleoli.

Lastly, if in many places the connection of living matter be
broken, — /. ^., the spokes uniting the single lumps be torn, — the

380 INFLAMMATIOX.

lumps become unfit for producing new elements, and are sus-
pended in a liquid, viz. : serum, derived from the blood which con-
stitutes suppuration proper. Pus, as is known, is destined to
perish.

The facts above enumerated lead to the conclusion that a
celhiJar Yfnthology, according to the theory of Virehow, cannot be
maintained, for in the tissues of the animal body there are no
''individuals," no ''cells," and conseciuently can be no isolated
'' cellular foci of disease."

Tissues are composed of living matter and its derivations. In
the center of the tissue-unit the living matter remains unchanged,
while at the periphery the living matter is infiltrated Avith basis-
substance. The continuity of li\ang matter is nowhere inter-
rupted ; the detrimental influence, therefore, which acts upon the
central body will also directly or indirectly reach the whole tissue-
unit, and vice versa.*

The changes which occur in the iufiamuiatonj process consist, first,
in a dissolution or liquefaction of the hasis-substance, and, secondly^
in an increased prodaction of the livinr/ matter of its own kind. As
I have previously demonstrated (see page 46), each lump of
living matter, no matter how minute, is capable of producing
its kind, ccmsequently to grow and form a new element. This
is true of isolated particles as well as of masses of living matter
combined into tissues and organs.

It yet remains to be proved whether or not certain '"free"
exudations of the animal body contain a number of extremely
minute, isolated lumps, which have been torn from connection
with the diseased tissues, and whether or not such lumps, under
certain conditions, are still vdable and endowed in any degree
with the capacity for reproduction. Together vnth. the emigra-
tion of colorless blood-corpuscles, such lumi)s may, perhaps, be a
source of the enormous new formation of pus-corpuscles.

It is always only the living matter ^vithin a tissue which is
subject to disturljances of nutrition, whether it is surrounded by
an interstitial li(iuid or by an interstitial solid basis-substance.
The non-living basis substance may undergo differeut changes,

' Later researches have proved that the chauges may take place under
certain conditions, first in the tissue-unit, before any change in the i)lastidhas
yet oecmTed. Even a portion of the plastid may exhibit inflammatory
changes, while the remaining portion continues in a nearly unchanged condi-
tion. (See article " Caries of Teeth, especially of Cementum.")

IMLAMMAJIOX. 381

l)ut it is liviiiii" niiitttT rxclnsivcly whicli is ('ii;il)l«'(l to I'cprodiicc
its kind, luul tlu-rcforc caicildt- of id-oduciiiu' the extensive new
t'orinations wliieh give rise to new tissues, such as pseudo-nietn-
branes, eallosities, ve«retations, ete.

It is not the eell and not the liviiiu- ])oiti()ii of the cell wliich
ah)ne j^tows and j)roliferates ; in the tissue, eveiythinu' that is
endowed with life can do so, consequently that portion of living
matter wlii(?h is inclosed by basis-substance also grows and pro-
liferates. To tliis extent, made clear by observations and infer-
ences, as far as connective tissue is concerned, we return to the
stand-point of Rokitansky, inasmuch as we admit that the so-
called " intercellular substances" are endowed with the capacity

of gTOAVth.

There /.s no re((soti, hoircrcr. to speali hereafter of a humoral
or soVidar patholof/i/, aiu/ tnore than of a eelhilar patholo(ij). There
exists but our patho/of/j/, and that is the patholoeffi of lirintj matter.
That onlji irhirh is aVwc rtoi Jx'comi' fhr siit)jecf of disease.

The Healing Process of Fractured Bones.

In several of my i)ublications, issued in 1873, and quoted in
the foregoing articles, iucideutal references are made to the
phenomena of the healing process in fractured bones, which I
propose here to include in one article. Later writers on this
sul)ject* have advanced no new views, as they have not con-
sidered the inflammatory process in the light of the bioplasson
theory.

My researches were made in the leg-bones of dogs, cats, and
raVil)its, which I fractured designedly while the animals were
kept under anaesthesia. In all instances I produced a displace-
ment of the broken ends, in order to induce a somewhat higher
degree of inflammation — the covering skin always remaining
intact. How the healing process of fractured bones progresses
by primary intention — /. e., when the broken ends are in close
C(mtact, — is not known. All the numerous observati(ms and con-
clusions concerning healing by primary intention in the soft
tissues require revision, as a thorough understanding of this
process is possible only through a knowledge of the minute
.structure of the tissues involved. None of the authors have had

* J. Hofmokl, "Ueber Callusbildung." Wiener Mediz. Jalirbiicher, 1874.
Here an exhaustive aecoimt of the literature on this subject is found.

382 IN FLA MM A TIOX.

this knowletljjc, stvaiige as it may appear. Throu^'h the kind-
ness of Dr. J. Lewis Smith, of New York City, I obtained two
fractured arm-bones of children, one of fourteen days', the other
of about four weeks', standing. I learned from these sj)ecimens
that the process of healing is in human bones identical with that
observed in animals.

Upon fracturing the bones of an animal, hemorrhage is pro-
duced, on account of the rupture of blood-vessels in surrounding
tissues, as well as those of the bone ; the initial swelling of the
tissues around the place of injury is known to surgeons to be
due to the extravasation of blood. The subsequent fate of the
extravated blood-corpuscles we do not know ; what we call
" absorption " of the blood is merely an expression of ignorance.

In the first few days following the injury inflammation sets
in, varying in intensity with the degree of displacement of the
ends of the fractured bone, and the general constitution of the
animal operated upon. The inflammatory process is most active
in the tissues which have the most abundant vascular supply —
i. e., the outer layer of the periosteum and the ru])tured muscles,
while it is less marked in the central medullary tissue of the
bone, and still less in its compact portions.

The result of the inflammation, as described in former arti-
cles, is that the involved tissues, and mainly the periosteum,
break down into medullary corpuscles, the same formation which
originally contributed to produce the periosteal tissue. By an
outgrowth of living matter, new medullary or inflammatory
elements are afterward produced, all of which remaining in
uninterrupted (ionnection represent the infffnnnxifor;/ n etc forma-
tion. The compact bone-tissue, in the immediate vicinity of the
fracture, is also melted out, and on the eighth day we see medul-
lary spaces, which are more or less numerous, and filled with
medullary or inflammatory corpuscles. These corpuscles are con-
nected with the inflammatory tissue arising from the periosteum
and the central man-ow.

In the second week the inflammatory elements, being identi-
(;al with medullary or embryonal corpuscles, form a new tissue,
in a manner already dwelt upon in the chapter on formation of
connective tissue. The result of tissue formation in this case is
again identical with that observed in the earliest stages of
embryonal life — /. e.. the meduUari/ tissue is trdnsfovmed into
cdftilage. Cartilage tissue appears after fractures, both of the
human and animal Ixmes, and constitutes the provisiotial cnllus of

IS FLA MM A I IDS.

\\K\

l>i(j)inj(r( II. Whcllu'i- siit-li ;i jii'ox isioiial t»f cai't ila^iiioiis callus is
ever formed, when the In-okeii Ixhk -ciids are closely fitting and
tlie ix'riosteuin Imt sliglitly iMJured, has not been determined.
This much is certain, however, tluit wlien a deviation of the
bone-ends Inis oecuiTcd, the foi'uiatioii of pi-ovisional callus is
invariably ])resent.

The manner in wliich the inflannnatory corpuscles are trans-
formed into cai'tilage (see paj^v 212) is l)ri(^f1y as follows :

Fig. 1(51. — Carth^aginous Callus ok the Bkoken Tibia op an Oli>
Cat, Fourteenth Day after Fracture. Chromic Acid Specimen.
[Published in 1873.]

B, slightly striatiMl basls-siibatance ; /, iJlastiil.s in tlie stagt; of iuiliffereuce, sliortl3'
before the t'onnation of basis-substauce; T', capillary blood-vessel in the luliMle of a medul-
lary si)ace. Magnitiod 800 diaiiu'tcrs.

At the places most distant from the Ijlood- vessels, the greater
part of which are newly formed, the originally globular cor-
puscles become elongated, and the nuclei of many of them dis-
appear. This is caused l)v the splitting of the solid bioplasson of
the nuclei into a reticulum, and the passing into the uniformly

384 INFLAM3IA TIOX.

^' graniilnv " stage of indifference. Usually such a change occurs
without a preceding coalescence of cor])uscles into territories.
Many of the indifferent corpuscles become infiltrated with basis-
substance ; l)ut we do not know whether this is of a gelatinous
or chondi-ogenous chai-acter. Some, however, remain free from
infiltration, at least in their central portions, and in this condition
constitute the cartilage corpuscles which are found lying at
nearly regular intervals throughout the newly formed basis-
substance. In the second week after the injury, we invariably
encounter nests of inflammatory corpuscles lying around a cen-
tral blood-vessel. The corpuscles nearest the vessel are more
globular, while the more distant ones are elongated and fusiform ;
we are able to trace all the stages of transition, from a uniformly
reticular bioplasson into an apparently structureless basis-sub-
stance. (See Fig. 161.)

In the above-mentioned groups or nests of inflammatory ele-
ments we observe the transformation of capillary blood-vessels
into solid cords, and subsequently the division of these into
smaller medullary corpuscles, which in turn also share in the
production of cartilage. This process is similar to the transmu-
tation in advancing age of capillaries into tissue.

The newly formed basis-substance of the provisional callus is
in part hyaline and in part striated. The striations are produced
either by the preservation of the boundary lines of the former
fusiform, indifferent elements, or by a splitting of these elements
into small spindles, within the territory, before the infiltration
with basis-substance had taken place. We notice bioplasson
bodies at regular intervals, which in this stage deserve the name
of cartilage corpuscles ; they vary greatly both in size and ap-
pearance. In some cavities of the basis-sul)stance we encounter
large, pale, nucleated plastids ; in others, smaller, shining lumps,
usually with vacuoles ; and in other cavities plastids are found
which are composed of a varying number of lumps of different
size. Lastly, ver}'- smaU cavities are seen in the basis-substance,
containing only a single yellowish, bright lump. All jDlastids,
whatever may be their size and shape, exhibit a distinct reticular
bioplasson structure, whenever they are nucleated ; all granules
and lumps contained in a plastid are likewise interconnected, and
from all plastids, without exception, delicate radiating spokes
arise, which penetrate the surrounding narrow rim, and are lost
in the basis-substance. (See Fig. 162.)

The newly formed cartilage of the provisional callus corre-

INFLAMMATION.

H85

s])()n(ls in its structure with normal liyaliiic or striated cartilage.
A striking' (litl'erenee, however, is tlisjdaycd in the tissue of the
provisional callus by the large amount of Ijioplasson it contains.
The (M)arse p;ranulation of even the nucleated ])lastids ; the
nuisses of bio^dassou lum})s lyin<jj in the (cavities ; the presence
of sinifle compact and vacu(ded
lumps in many of the cavities are all
un(iuestionably due to the great
augmentation of living- matter pro-
duced l)y the intiammatory process.
Such irregular formations are never
met with in normal hyaline or stri-
ated cartilage. They can be ex-
plained only by the different phases
of development which the bioplasson
lumps undergo. (See page 4().)

That the newly formed cartilage
has really to a great extent sprung
from former periosteal tissue is
proved by the presence of unchanged
elastic tibers. The cartilage tissue
is traversed by a vaiying number
of single, sometimes bifurcating,
straight, glistening fibers, which
either divide the tissue into more or
less regular rhomboidal fields, or are
scattered through it without uni-
formity. There is scarcely any doubt
that these elastic fibers originally
belonged to the periosteal tissue,
and remained unaltered T)y the in-
flammatory process. They also eou-
tinue unchanged even after calcifi-
cation of the cartilaginous tissue
has taken place — nay, even after this tissue has retrogressed to
the medullary state, the fibers often traversing the newly formed
medullary spaces without any apparent regularity.

In the thii'd week after the fraetiu-e, a calcareous deposition
takes place in the tissue of the provisional callus. Its extent varies
greatly in different individuals, and sometimes it is very scanty,
though never entirely wanting. In the fractured humerus of
a child, during the fourth week after the injury, the calcifica-
25

Fig. 1 62.— -Cartilaginous Cal-
lus, Fourteen Days after
THE Subcutaneous Fract-
ure OF THE Tibia of an
Old Cat. Chromic Acid
Specimen. [Published in
1873.]

a, plastiil with several formations
like nuclei; b, vacuoleii, sliiniug plas-
tiil ; c, ])la8ti(t, composed of numerous
small, brifilit frianules ami lumps ; d,
minute bioplasson luni}) in a cavity of
basis-substance. Magnified 800 diam-
eters.

386 INFLA MM A TION.

tioii had pervaded a large amount of the newly formed cartilage,
while in other places the formation of medullary spaces and of
trabeculae of bone was observed — the latter, however, only on a
small scale.

Simultaneously with the deposition of lime-salts, and often
independently of it, a peculiar change is observed, at nearly reg-
ular intervals, in certain points of the cartilage tissue — viz. : the
formation of red hlood-corjjusclesj of blood-vessels, and also of
medullarji tissue. Those portions of the cartilage tissue which
exhibit, in the basis-substance, at an earlier stage, the greatest
number of small bioplasson lumps, and which have, to all appear-
ance, sprung from former capillary blood-vessels, show the most
marked new formations of blood and blood-vessels.

Nests of medullary or indifferent corpuscles, or multinuclear
bioplasson masses, are found, exhibiting an active outgrowth of
living matter. This divides into small lumps, which subsequently
imbibe haemoglobin, and constitute, first, haematoblasts and, later,
red blood-corpuscles (see page 98). The peripheral portions of
the plastids, or the multinuclear masses, are changed into flat,
thickened layers of bioplasson, which lay the foundation of the
walls of blood-vessels. Such a wall, in the optical section, exhib-
its slight fusiform thickenings, indicating, perhaps, the future
nuclei of the endothelia. Club- and rosette-shaped formations of
this kind are at first connected with older blood-vessels by means
of solid, bright cords of living matter, which, after they are hol-
lowed out, establish a communication between the newly formed
blood-vessels and the older ones. (See Fig. 163.)

Together with the appearance of l)lood-corpuscles and blood-
vessels, and the deposition of lime-salts in the basis-substance of
the cartilage ("osteoid tissue" of authors), the new formation of
medullary spaces is inaugurated. Around the newly formed
blood-vessels, or independently of them, the cartilage tissue
breaks down into medullary elements, solely in consequence of a
dissolution or liqiiefaction of the basis-substance. The newly
appearing medidlary corpuscles are the same which, at an earlier
date in the healing process of the fracture, produced the cartilage
tissue.

By a continuous dissolution of the calcified basis-substance,
the medullary spaces are enlarged and the medullary cor-
puscles augmented by a growth of living matter. In the cen-
tral portions of the medullary space the corpuscles produce
new blood-vessels, if such had not previously formed. The

IXFl.AMMA'noX.

:{87

process is exactly like that of the iioi'iiial dissolution of carti-
lage, whii'li leads to the new formation of medullary tissue, and
suV)se(iuently of bone.

Meanwhile, at the fractured surfaces of the bone, similar
medullary s})aees have formed in conse({uence of the dissolution
of the l)asis-snbstance of the ))one and an increase of its bioj)las-
son material. The connection of the irregular, bay-like medul-
lary spaces of the l)one with those of the adjacent calcified
cartilajife <'an be traced directly.

From the medullary tissue, which is the offspring of the

Fig. 163,— Cartilaginous Callus, Eighteen Days after the Subcu-
taneous Fracture of the Tibia of a Cat. Chromic Acid Specimen.
[Published in 1S73.]

'', cartilajfo eorimscles in a striated Uasis-siibstauce; 3f, elongated medullary i>laHtid8,
tendinfr toward tlie formation of ba8i.s-.substauce, or resulting from a dissolution of basis-sub-
stance ; JS', B", club like spaces, lined by a continuous bioplasson layer, containing hsemato-
blasts and red blood-corpuscles. Magnified 800 diameters.

inflamed periosteum, bone-tissue arises, in exactly the same man-
ner as in the normal development of bone (see page 247). This
hone-tissue establishes the formation termed definitive callus (Du-
puijtrenj.

The trabeculae of bone in children and animals begin to
appear in the fourth week after the fracture ; these at first are

388

INFLAMMA TION.

very irregular formations, exhibiting an indistinctly striated, cal-
cified hasis-sn])stance and very large and irregular bone-corpus-
cles. The medullary spaces are filled with medullary corpuscles,
and contain, in their centers, newly formed blood-vessels, which
are smaller the nearer they approach the compact structure of

Fig. 1G4. — Exostosis after Periostitis of the Tibia of a Dog in the
Fifth Week of Inflammation; Identical in Structure with the
Definitive Callus. Chromic Acid Specimen.

C, superficial compact layi^r, witli HH, the Haversian systems, and -S'.V, newly formed
medullary siiaces; H, A-ascular canals, widened into medullary spaces, S; r, trabeculae ol
newly formed bone, with larf?e and irregular bone-corpuscles, inclosing large medullary
spaces, Mfi. Magnified 200 diameters.

the injured bone. Unquestionably, also, the injured muscle-tis-
sue shares in the formation of both the provisional and the defin-
itive callus, always through the intermediate stages of medullary

INFLAMMATION. 389

tissue. The newly foriiied tt-abeeulii' of bone jire in every respe(;t
identical to those o])serve(l iit'ter plastic periostitis, and in this sit-
uation termed ''exostoses" and " osteo])hytes." (See Fig. 164.)

The connection between the old and the new bone is estab-
lished at the fractured snrfaces by direct inosculation. At the
surface of the compact bone, however, bay-like excavations are
often wanting, and the newly formed bone may be attached to
the old bone without the latter exliibitinjj^ any marked inflamma-
tory chan<j:es. This occurrence has misled some authf)rs into
the belief that the newly formed bone is simply in apposition to
the compact structure of the old bone, without being directly
connected with it. Such views nuist, be the result of the study
of dry specimens, for in all other preparations there is no diffi-
culty in ascertaining a direct union of the newly formed bone-
corpuscles with the old ones by means of anastomosing offshoots.

The originally irregular and l)ulky new formation of bone,
gradually — viz. : after several months — is transformed into a
more regular osseous structure. This can be explained by the
supposition of repeated dissolution and new formation of bone-
tissue only. After the lapse of several years the bony cicatrix
becomes so perfect, and even supplied with a central marrow-
space, in continuity with the old one, that, were it not for the
deviation of the fractured ends, no trace of the former accident
could be discovered.

My researches may be summed up in the following state-
ments :

(1) The injury done to the bone and the adjacent soft tissues
by the fracture leads to an inflammation, which is most intense
in the most vascularized tissue — \'iz., in the periosteum ;

(2) The inflammatory new formation results in the produc-
tion of a medullary or inflammatory tissue, from which arises
cartilage tissue, representing the formation termed " provisional
callus " ;

(3) The cartilage tissue at certain regular intervals, which
depend upon the new formation of blood-vessels, is broken down
into a freely vascularized mediillary tissue ;

(4) The meduUary tissue, which has sprung from the former
cartilage, produces bone, first in the form of irregular trabeculae,
constituting the formation termed "definitive callus'' ;

(5) The formation of the definitive callus is in all essentials
like the formation of bone in the process of normal ossification
from cartilage and periosteum.

390 IN FLA MM A TION.

Necrosis. By C. F. W. Bodecker, of New York.*

The successful study of the elements of bone-tissue depends very much
upon the method emjjloyed. The proper examination of bone-tissue origi-
nated in the second, third, and fourth decade of this century, and was pursued
by Howship, J. Miiller, Henle, and others ; all of whom resorted to dry bone,
which they divided into thin slabs by the use of the saw, after which these
were gi-ound thin by a variety of devices, reducing each sj>ecimen to semi-
transparency. Observations made in this way resulted in the theory of
caualiculi bearing a solution of lime-salts. In 18.50 and J S.lli, Rodolph
Virchow and F. C. Donders applied the cell doctrine of Schwaim to the
explanation of bone-tissue. They sometimes used dry and sometimes fresh
bone in their investigations, macerating it in dilute hydrochloric acid, where-
by they liberated the elements of the structure more or less distinctly. The
bodies so isolated presented, sometimes, nucleated structures connected
together by branches ; at other times, completely isolated bodies consisting
of a central mass with projecting processes, and to these they gave the name
bone-cells. Donders drew attention to the fact that bone-tissue had spaces
filled by cell-like structm-es similar to those of other kinds of connective
tissue. E. Neumann, in 1863, asserted that the so-called bone-cells were
not the cells designated by Schwann, but spaces with offshoots having a
more densely calcified wall than the other basis-substance, and thus better
able to withstand the re-action of solvents. These bone-cells are no other
than the lacunas, and their offshoots, the canaliculi. Inasmuch as the dry
method of examination of bone-tissue prevailed up to the introduction of the
wet method, by Heinrich Miiller, in 18.50, it is not surprising that it is fre-
quently persisted in to this day. The nearer to the living state the examina-
tions can be made, the more instructive and definite will tlie observation be.
Hence the dry method is fast falling into disuse among tliose making histo-
logical researches. In 1S71, E. Lang introduced the examination of living
bone under the microscope upon the heated stage, by which he noticed
amoeboid motion in bone-corpuscles. By this management the lacunae were
proved to contain protoplasm, Vjut the nature of the contents of canaliculi he
said nothing about. The method of examining bone-structure introduced by
H. Miiller — viz., to decalcify bone by the use of a solution of chromic acid —
is to be preferred. In this way bones are decalcified in a short time, and
without considerable change. For thin bones, two or three weeks are sufficient
to soften them enough to produce sections of any degree of thinness by the
use of the razor. Such sections may be stained by placing them in a solution
of chloride of gold, of one-half per cent, in strength. An examination of such
preparations will show that, within the lacunae of the bone, nucleated bodies
are to be seen, with finely gi-anular offshoots extending into the larger canal-
iculi, where they are lost to sight. From the surface of the bioplasson body
in the direction of the basis-substance many conical processes protrude
toward the small canaliculi, with which they blend. In 1872, C. Heitzmann
described and illustrated a bone-corpuscle fi-om bone in the early stage of
inflammation [see page 112(), Fig. 40, of this book]. This figm-e shows very

* Abstract from " NecrosLs," by C. F. W. Biideckcr, D. 1). S., M. D. S., New York.
"Dental Cosmos," Philadelphia, 1878. lu order to establish uuiformity throiiifliont tlie book,
the term " protoplasm " is chaiiffed into that of " bioplasson."

IM LA MM ATI ox.

:{!»1

plainly the shining, nt-arly homogeneous-looking bone-corpuscle, with off-
slioots in every direction, filling the whole enliher of the caiialiculi. It solves
the (piestion of the contents of the canaliculi in bone by direct observation.
The living matter in bone beiiaves precisely as in other tissues under the
inrtut'iice of the inflammatory ])rocess — that is to say, the central mass
becomes a shining and nearly homogeneous lump, the offshoots from which
occupy the whole caliber of the canaliculi, and by this the analogy of V)one
to all otlier varieties of connective tissue is established. That is to say, here,
as elsewlu're, the living part of the bioplasson forms a continuous net-work
througliout the whole animal body,
in the meshes of which a more or
less fluid basis-substance is found,
differing in its chemical properties
in different situations, which in
bone is glue-giving, and infiltrated
with lime-salts.

I have followed the methods, in
my examination of bone tissue, as
above described. This enabled me,
by the use of the razor, to obtain
sections fit to be examined by an
immersion lens magnifying SOO to
10(M1 diameters. I noticed that the
canaliculi could be plainly seen in
sections, the basis-substance of
which had retained a small quan-
tity of lime-salts ; in completely de-
calcified specimens they are very
faintly discernible. According to
my experience, it is better to stain
the sections with a solution of chlo-
ride of gold of the half of one per
cent., whereby a better view of both
bioplasson and basis-substance is obtained
sections with carmine and hfematoxylon.

The results of my observations with high magnifying powers are that bone-
tissue presents faint parallel lines, dividing it into the so-called lamellae,
within which we find the bone-corpuscles, the shapes of which vary according
to the direction of the cut and of the lamellae. As bone-corpuscles are flattened
lenticular bodies, we will recognize them in this shape in the fi-ont view only.
Longitudinal sections through these bodies give a spindle-shaped outline,
small when cut near the boundary, broad when cut thi-ough the middle line
of the lentil. A cross-section through a bone-corpuscle shows a somewhat
irregular body. A cross-section fi-om the compact bone of a lower jaw
presents invariably bone-corpuscles in all three varieties. (See Fig. 1 Go.)

We see large spaces, showing a nimiber of ray-shaped offshoots. Besides
these coarse offshoots, innumerable extremely fine light ones are present. The
larger as well as the smaller all communicate with each other, forming a deli-
cate net-work through the whole of the basis-substance. Within the lacuTia*
are present " protoplasmic " bodies. We observe, in the centers, shining
oblong nuclei and nucleoli. Around the nuclei we see a narrow seam, trav-

FiG. 165. — Normal Bone-tissue op
THE Lower Jaw of a Man, Aged
Thirty Years. Chromic Acid
Specimen, Stained with Chloride
of Gold.

Three boiie-corimscU's, 7'', with an oblonj?
mirleus ; P2, witli a globular nucleus, both ex-
liibiting indistinct nucleoli : /"a, with a small,
i-onipact nucleus. Majrnified 1000 rtianieters.

Another good way is to stain the

392 INFLAMMATION.

ersed by numerous very fine threads, which are cone-shaped. Tlieir bases
are directed toward the nucleus, from the periphery of which tliey arise, wliile
their points are in connection with the nearest granules of the protoplasm.
Within the corpuscle there are finer and coarser granules, all being connected
with each other by very fine threads. The seam around the nucleus, as well
as the spaces between the meshes of the threads, are observable, being much
lighter than the latter.

From the periphery of the bioplasson body numerous thick offshoots enter
the larger canaliculi, which sometimes can be followed up until they commu-
nicate with the bioplasson of other large neighboring canaliculi. Besides
these, many very fine offshoots run from the periphery of the bioplasson, con-
tained in the larger canaliculi towards the basis-sul)stauce. Some of them
can be seen to enter the fine canaliculi, but their course cannot be distinctly fol-
lowed. My preparations show a much finer net-work within the basis-substance
than Heitzmann's figure, before alluded to. Though I am not able to distinctly
demonstrate the presence of living matter in the finest canaliculi, yet, as we
find it in all other kinds of connective tissue, I am justified in assuming it. In
normal bone, the laeunse and canaliculi are not entirely filled by the living mat-
ter. On the periphery of each corpuscle we see a distinct light seam, traversed
by the offshoots, which, in a cross section, only show the bioplasson in the center
of the canaliculis, hence lea\ang sufficient space for the nutrient circulation.

It is impossible to study the differences between necrotic and normal
bone if the specimens be prepared from dry osseous tissue.

I have made microscopical examinations of necrotic bone from the lower
jaw, and from another piece from an upper jaw removed by Dr. Frank Abbott.
The methods employed were exactly the same as before described from nor-
mal bone. In both cases the necrotic sequestra, as soon as they had been
taken from the mouth, were placed into the solution of chromic acid, and cut
in due time. As these pieces were small, I imbedded them in a mixtui-e of
paraffine and wax (after the extraction of the water by treatment with alcohol
for twenty-fom* hours), whereby I was enabled to obtain extremely thin sec-
tions, some of which I stained with chloride of gold, some with heematoxylon,
and some I mounted unstained.

The results of these examinations were as follows :

The outer sm*face of the necrotic bone, which, to the naked eye, looked
rough and eaten out, when brought under the microscope showed bay-like
excavations, known formerly as " Howship's laeimae," in which there was
visible a granular mass mixed with pus-corpuscles. In the middle of the bone
I found all the Haversian canals more or less enlarged, some showing the bay-
like excavations. The contents of the Haversian canals were every^vhere the
same — a conglomerate mass of darkly shaded gi'anules, which I was imable
to stain with carmine. These masses are the same that we see in decomposi-
tion of organic matter — "micrococci." Here and there some medullary cor-
puscles and multinuclear bodies were recognizable. I did not see blood-vessels
in any of the Haversian canals. In the necrotic bone I found the traces of
former osteitis. The enlargement of the Haversian canals and lacunje are
direct proofs of this ; the dissolving out of the basis-substance on the per-
iphery may, on the contrary, have been due to chemical changes, produced by
infiltrations from the neighboring inflamed tissues. The Haversian systems
and concentric lamellae were unchanged. The lacunas and canaliculi were yet
preserved. In the necrotic preparation from the lower jaw I observed many

INFLAMMATION.

:}93

lacunn? in which the biopluMSOii body, witli its not-work, was yet diKtiiiKi'inh-
al)U', esjuHMally wliere the sequestrum had been attached to the periosteum.
I found, also, in the preparation from tlie upper jaw, some comparatively
unchau'^ed bone-corpuscles.'' But the majority of the bone-corpuscles, and
especially in the ueigliborhood of the Haversian canals, were either empty or
their bioplasson boilies were sliriveled up (probal)ly the remains of the liviiif^
matter), only showing a few coarsti granules. (See Fig. 100.) No signs of
fatty degeneration could be seen, for
the gi-anules were stained violet by
cliloride of gold. Many lacuna'
showed no structure at all, the con-
tents looking rather like a mass of
coagulated albununi. In none of these
hicuua^ was the cliai^acteristic struct-
ure of bioplasson recognizable.

To sum up my observations, I
found :

First. The lacidia' contain a bioplas-
son body, tcith a distinctly risible net- -^^
like arranffcmoit, to be regarded as the
liring matter proper.

Second. The basis -substance is
pierced by numerous coarse and fine
canaliculi, coniniunicating with each
other, as well as with the lacuna'.

Third. The bioplasson bodies, which
do not quite fill the lacunce, send off-
shoots of the living substance into the

Fig. 166. — Necrotic Bone-tissue of
THE Lower Jaw of a Woman, Aged
Thirty-eight Years. Chromic
Acid Specimen, Stained vp-ith
Chloride of Gold.

Three lacuiisc : Xi, with two clusters of a

canaliculi, but can only be seen in the granular mass; m with scanty granules ; £3,

with a nearly homogeneous mass. Magnified
coarser ones. io„o diameters.

Fourth. In necrotic bone, traces of
former osteitis are visible, but no blood-vessels present in the Haversian canals,
which are filled with micrococci.

Fifth. In necrotic bone, ntost of the lacuna; contain no bioplasson, but either a
coarsely granular or a structureless mass — remnants of the living matter and
coagulated albumen.

Rachitis and Osteomalacia.

During the years of 1872 and 1873, I made a number of
experiments, for the purpose of ehieidating the causes of rachitis
and osteomalacia. The results of these tedious and expensive
experiments I published in 1873, in the form of a provisional
communicatiou.t

* An important feature is not mentioned in this article — viz. : tliat even in apparently
unchanged bone-corpuscles the nuclei were Jagged, as if shriveled, this suflBciently indicating
death of bioidassou.— Kd.

t Anzeiger der Akadeniie d. Wissensch. in Wien, 19 Juni, 1873 ; und Vortrag in der Ge-
sellschaft d. Aerzte in Wien, October, 1873.

394 INFLAMMA TIOX.

Marchand, Ragsky, Lehman, Simon, and others, found free
lactic acid in the urine of persons affected with either rachitis or
osteomalacia. C. Schmidt discovered lactic acid in the liquid
of malacic shaft-liones wliich had been transformed into globular
cysts. Based upon these researches I commenced, in April, 1872,
a series of experiments on the influence of internal administra-
tion and subcutaneous injection of Jacfic acifJ oh the hones of
Jiriiu/ ((iii)tials. These experiments were continued till the end
of October, 1873, and were made on five dogs, seven cats, two
rabbits, and one squirrel.

The result was that in dogs and cats, in the second week of
the administration of lactic acid, no matter whether introduced
with the food or by subcutaneous injection, the quantity of
lime-salts given with food being simultaneously reduced, swell-
ings appeared in the epiphyses of the shaft-bones of the extremi-
ties, and at the insertions of the rib-bones into their cartilages.
The enlargement of the epiphyses and tlie riljs increased con-
tinually up to the fourth and fifth week, and at the same
time curvatures of the bones of the extremities were noticed.
Catarrhal inflammation of the conjunctiva, the bronchi, the
stomach, and the intestines, emaciation and twitching of the
extremities, were the concomitant symptoms.

The microscopical examination of the epiphyses demonstrated
the identity of this pathological process A\ith that seen in the
epiphyses- of rachitic children.

On continuing the administration of lactic acid, the enlarge-
ment of the epiphyses of the long-bones decreased, and the
shafts themselves became, to a certain degree, less curved, while
catarrhal inflammations of the mucous membranes occurred
repeatedly. After four or five months, softening of the shaft-
bones set in to such a degree as to render the bones as pliabh'
as willow-boughs. The microscopical examination of the bones,
after administration of lactic acid, continued for four to eleven
months, showed a condition of things identical to that seen in
human beings, dead of osteomalacia.

In the three herbivorous animals no swelling of the epiphyses
was observable. One rabbit died in the third month, the other in
the fifth month, of the administration of lactic acid, both having
svmptoms of inanition. In the bones of these animals there were
no marked signs of rachitis or malacia. The squirrel, on the con-
trary, which died after thirteen months' treatment with lactic acid,
exhibited, in a high degree, the characteristics of osteomalacia.

IM'LAMMATIOX. ;il),j

From these experiments it follows that we are able to prodiiei
4irfitiri((lli/ in enrnirorons aiiinidls, Jxj eoutinned uiJtiiitiistrniioti of
lactic acid, firsts rachitis^ aiid afterward osteomalacia ; icliile iti
herhivora the same (Ujent prodaees osteomalacia without a j>relinii-
nary rachitic statje.

Thus, tlu' identity of these foi-ms of disease is demonsti'uted.
and tlie differences in their course (U'pend niaiidy upon the differ-
ence in the age of the animals in which the sohition of the lime-
salts is ])roduced.

In October, 1873, I exhibited to the Society of Physicians, in
Vienna, a female foetus of seven months, which had died immedi-
ately after birth. The mother of this foetus had been employed
by me for months to feed the animals with lactic acid. In this
foetus the symptoms of congenital rachitis were in the highest
degree marked, to such an extent that the skull- bones were
entirely absent, the cartilages of the ribs and the extremities
showed only scanty depositions of lime-salts, but numerous
breaches in the continuity; and throughout the body of the other-
wise well-developed foetus there could be found no trace of bone-
tissue.

Feeding with lactic acid was repeated by E. Heiss,* on a dog
one year and six months old, with only negative result. The age
of dogs and cats in which rachitis can be induced is between the
fii-st and six months of life — at the period, therefore, when the
skeleton is developing from the cartilage and the periosteum.
After this stage of development is passed, the symptoms of osteo-
malacia will be produced, and with greater certainty, toward the
end of the first year of the animal's life. The experiments of
Heiss rest on mistaken grounds. Age is an essential factor in
the production of either of these diseases in human beings.
Rickets occurs only in children l>etween the first and the fifth
years of life, this corresponding with the age of the above-named
animals. Osteomalacia is exclusively a disease of adults.

Rachitis (Rickets J. This disease of early childhood in its clin-
ical features has been well known for over two centuries.

Whistler t was the first to describe it, and from the title of his book the
name of "English disease "was adopted by the German physicians. Next
followed G. Glisson,t who made nse of the name " rhachitis."

Simon,§ according to Marchand and Lehman, found lactic acid in the urine

■ '• Zeitschr. f. Biolofrii-," Bd. xii.

t '■ Df Morlio Puerorutn Aiifrl<>riiiu," 164,5. Rare book.

t 'Tractatus de Rhacliitiile," 1659.

? LelnbiKh d. Med. Clieinic. 1842. Bil. ii.. i>. 203.

396 INFLAMMATION.

of rachitic children. He says that such ehihh-en void urine which sometimes
is very rich in lactic, also in oxalic, acid, and that it contains four times as much
phosphate of lime as the normal urine of children. Kiekets may be caused by the
formation of lactic acid in the digestive tracts ; certainly this acid is not dis-
posed of in the blood, in which only a small portion of the nitrogenous mate-
rial is transformed into urea. In osteomalacia of adults, the lactic acid in the
urine is considerably augmented, as well as the uric acid. In rickets, the
lactic acid dissolves the phosphate of lime of the bones, and these become pli-
able ; while, in osteomalacia, even the organic portion of the bone is in part
absorbed.

Gr. O. Rees* gives a thorough chemical analysis of the earthy phosphates
in "Mollities ossiuni." He found the resorption of the phosphates to be
different in different bones, and in the softened bones, on an average, he
found only 78 per cent, of the normal 86 per cent, of phosphate of lime.
The absorption, he says, affects the carbonate less than it does the phosphate
of lime.

Chossat t observed the absorption of lime-salts in pigeons which had been
fed exclusively on wheat. The " rarefaction" of bone corresponds more closely
with osteomalacia than it does with rickets. Dian-hoea was a concomitant
symptom of this disease. Sam. Solly t distinguishes two varieties of softening
of bone. Osteomalacia, he says, has also been observed in animals by
Spooner, especially in dogs, with post-mortem results identical with those
found in man. Sometimes the disease is confined to single bones.

C. Schmidt ^ found the lactic acid by combining it with zinc, in the acid
liquid of cysts into which the malacic bones were transformed, and he
thought that the lactic acid was of local origin. Ernst V. Bibra || observed,
in accordance with the experiments of Chossat, that by withdrawing the lime-
salts from fowls the lime-depositions in the egg-shell disappeared, and finally
the fowls ceased laying eggs altogether. The bones of chickens showed a
decrease of about 10 per cent, of the inorganic substances and a decrease of
6 to 10 per cent, of tlie phosphate of lime; while the carbonate of lime and
phosphate of magnesia were only a little lessened, and the alkalies and the fat
not at all. V. Bibra found no lactic acid in fresh bones ; no consideration is
given to this acid in his chemical analyses.

J. Schlossberger H obtained the following results : In the normal occipital
bone the percentage of inorganic material never falls below 60 per cent. In
eraniotabes the percentage sinks to 51-53 per cent., and in the spongy and
thickened portions to 4.3-48 per cent. Carbonate of lime is either decreased
or normal.

Guerin' says that if young animals are given other food than milk, dis-
turbances of nutrition, especially of the bones, will follow. He took pups of
the same litter, and fed some with exclusively animal and others with mixed
vegetable food (bread and milk). The latter remained healthy ; the former

* Guy's Hosp. Reports, viii., p. 191. Schmidt's Jalirb., 1841.

t Comptes rendus. Tom. xiv., \i. 451^54.

% Med.-Cliir. Transactions, xxvii. 2fl Ser., ix., 1844.

§ Annales de Chem. et I'harm., Ixi., 3, 1847.

II " Cliem. Untersucli. iilji^r di« Knoclien u. Ziilino des Menschen u. der Wirbelthiere."
Schweint'urt, 1844.

Tf " Chemisclie Untersuchuiigen iiber d. erweicliteu Kiiideiscbiidel." R. u. W. Arch. viii.
Schmidt's Jahrb., 1849, Bd. Ixil., p. 277.

1 Gazette des Hdpltaux, xxxvii., 1848.

IN FLA MM . I nox. 397

at. first grew rapidly, but soon diarrha'a set in, they emaciated and beoame
raeliitic. The bones l)ecanie so soft tliat the animals walked on their femurs
and humeri, wliieh were very much curved. The main cause of rachitis,
accordiuff to this autlior, is animal food, pfiven too early.

G. Wef»ener ' made experiments on fowls and calves, producing rachitic
changes by the administratioji of small doses of phospliorus, continued for
months. He found the epiphyseal cartilage considerably dissolved out, and
also in a high degree of hyperaunia.

The histology of rachitic bones has been studied by many excellent
observers, such as H. Meyer, K. Virchow, H. Miiller, A. Kolliker, C. Wedl,
Steudener, and others. H. Meyer t especially comes to the conclusion that :
(1) osteomalacia is osteoporosis ; (2) rachitis originates from universal peri-
ostitis ; (3) osteomalacia and rachitis are the consequences of one and the
same disease.

We know that, in the normal process of ossification, both car-
tilage and periosteum are reduced to a juvenile condition, <fiving
rise to medullary tissue. Simultaneously, also, new red blood-
corpuscles and blood-vessels are formed. In richets, all this is
(joimi on in a more rapid manner, hut the new formation of hone
from the niedulJari/ tissue is very scanty or entirely absent.

In sagittal sections of the epiphyseal ends of rachitic bones
we notice an intensely yellowish-red zone on a level with the
portions in which the formation of meduUary tissue from carti-
lage is going on, and we see that this portion is considerably
thickened, constituting the characteristic rachitic swelling of the
shaft-bones. Under the microscope we find, at the level men-
tioned above, large cartilage corpuscles containing a far greater
amount of bioplasson than normal. The calcification of cartilage
is scanty and in irregular patches, or sometimes completely
wanting. The large, irregular, newly formed medullary spaces
abound in hollow, club-shaped formations — the future capillaries
— : which contain numerous hnematoblasts and red blood-corpus-
cles. At the peripheral portions of the epiphyseal cartilage a
new formation of vascularized cartilage, instead of bone, can be
traced, while the newly formed trabecule of bone are scanty,
irregular in shape, holding large bone-corpuscles and territories
with distinct boundary lines. Similar features are observed at
the points of junction of hyaline cartilage and bone in rachitic
ribs. Here, too, the new formation of cartilage is proceeding
from medullary tissue on a large scale, mostly in groups, repre-
senting the territories. The cartilage is dissolved out, leaving a

" Virchow's Archiv, Bd. Ivi.

t "Zur Lebre von den Knoclunkiankeiten." Henle u. Pfeififer's Ziitschr., iii., 1853.

398

IXFLAMMATIOX.

medullary tissue freely supplied with blood-vessels of considera^
ble caliber, venous and capillary chiefly ; but the production of
bone from this vasculai'ized tissue is extremely scanty and with-
out uniformity. (See Fig. 167.)

At the peripheral portions of the shaft-bones we find, between
the thin cortical bone-tissue and the fibrous portion of the perios-
teum, a broad layer of medullary tissue, which is sometimes
arranged in patches. The blood supply of this medullary tissue
is so great as to give the appearance of a hemorrhage to the

j?r

V3

Fig. 167. — RAcmTis. Rib of a Child, in Tra>-verse
Section. Chromic Acid Specimen.

C, cartilage cori>uiscles, an-anged in territories : -V.S, mertullary space, sprung from carti-
lage tissue ; M, nieilullary tissue with very large blood-vessels, £V. anil a scanty new forma-
tion of Vwne-tissue, B. Magnified 200 diameters.

naked eye. The bone generally remains in the stage of cancel-
lous structure, with large, irregular medidlary spaces.

The flat skull-bones, being developed from fibrous connective
tissue, exhibit similar features — the so-called crnniotnhes. In
some pla<?es medidlary tissue is formed, leading to a reproduction
of fibrous connective tissue, instead of bone ; or ab-eady formed
bone, through the intermediate medullan,- stage, passes into a

IX FLA MM A n (L\. :}1)9

new format ion of fibrous coiiiioctivc tissue, resulting in thiniiii)<i-
of the hone. In other places tlie exul»ei-ant <i;ro\v'tli of niediillai'V
tissue eatises a broadening; of the <lianieter of the })one, witli a
seanty trabeeuhir new formation of })one-tissue. Both the medul-
hii-y and tlie newly formed eonneetive tissue are supplied with a
eonsidci'ably liirj^-cr amount of l)lood- vessels than is seen in the
nornuil eondition.

The pathoh>gical eondition is that of aplastic inflammation, in
accordam-e with the views expressed by Virehow, and there is good
reason to consider the process of rachitis as an intiammation.

By feeding pups and kittens wdth lactic acid, rickets was
induced, exhibiting in the osseous system features identical to
those observed in racliiti(! children.

Ostfonidhirid. This rare form of disease, which is always
accompanied ))y intense pains, usually attacks the vertebral col-
umn and the pelvic bones, though there are cases on record in
which the whole skeleton was rendered as pliable as wax.

Under the microscope we see a decalcification of fully formed
bone-structure, usually of the compact portions, advancing in a
way similar to the inflammatory process. The bone-tissue is
transformed into medullary tissue, which in some places is distin-
guished by a large quantity of blood-vessels. My researches
enable me to state that the ultimate productions from medullary
tissue are of two kinds : either colloid glol)ules or simply fibrous
connective tissue.

In a femur of a woman who, during pregnancy, was attacked
with osteomalacia, and died of the disease, the compact portion
of the bone was reduced to the thinness of a pasteboard, and
was very pliable. The central marrow space was filled with a
smeary, grayish yellow mass, which, under the microscope, proved
to be colloid — viz.: consisted of globular or irregularly shaped
corpuscles of a luster similar to fat, but not yielding to the
re-agents which dissolve fat. They resisted even the action of
strong alkalies and acids which destroyed the bone-tissue proper,
and assumed a dark purplish violet color upon being stained with
chloride of gold. (Fat is unaffected by chloride of gold.) Within
the globules radiating bodies were often seen, somewhat similar
to the needle-shaped crystals of the so-called margaric acid.
Between the globules scanty fibrous connective tissue with a few
blood-vessels was noticeable.

The origin of the colloid corpuscles could be traced in the thin
compact shell of the femiir, in which the lamellae were much

400

INFLAMMA TION.

more marked than normal, evidently due to a dissolution of the
lime-salts during life. Numerous medullary spaces, containing
a varying number of colloid corpuscles, traversed the bone.
Some of these bodies exhibited faint traces of the medullary cor-
puscles which composed them ; others, in the initial stage of the
colloid metamorphosis, were distinctly seen, consisting of medul-
lary corpuscles, so that each colloid body might be considered
as having originated from a group of coalesced medullary cor-
puscles. In some places long
rows of colloid corpuscles were
noticeable, each of which re-
sembled a territory with a
condensed, peripheral colloid
frame, and a central body,
somewhat like a bone-corpus-
cle. (See Fig. 168.)

In the rib-bone of another
woman, dead of osteomalacia,
I found very large medullary
spaces, which were tilled partly
with medullary and partly with
fibrous tissue, and contained
also a number of yellow-brown
pigment clusters. These spaces
were very vascular. In this
case no colloid corpuscles could
be detected.

In dogs and cats, whose
bones were artificiaUy brought
into the condition of osteomal-
acia, all featiu-es described
above as occurring in the mal-
acic femur of the woman were
present, and especially the col-
loid globules. These closely resemble fat-globules, l)ut, never-
theless, were an entirely different substance, as they did not jdeld
to strong alkalies and acids, not even after being boiled with
them. Chloride of gold stained them a dark purpUsh-violet
color. The bones of the squirrel, which had been fed for thirteen
months with lactic acid, had compact portions as thin as paper.
They were, to a great extent, transformed into meduUary and
fibrous tissue; they contained a large number of blood-vessels

Fig. 168.— Osteomalacia. Femur of
A Woman ; Longitudinal Section.
Chromic Acid Specimen.

B, boiie-corpuscle ; L, distinctly luaikeil la-
mella ; C, colloid corijuscles, arranged in a row.
Magnified 500 diameters.

IM'LA.yMATlOX. 401

an<l )ti«rnu'nt clusters, Imt no colloid corpuscles. Tlie rcsein-
hlaucc the case bore to the second case ot nialaeic ribs was very
strikiuiT.

In conclusion. I wish to say a few words as to tlic withlioWuif? of lime
food in the animals expcrimenti-tl upon. It was, in fact, only a reduction.
Init not l)y any means an entire cutting off of the lime sui)i)ly. The dogs and
cats were fed with fresh V)oiled meat, with fat, with milk and white bread ;
V»ut no bones were given. The desire of all these animals for lime food,
during the treatment with lactic acid, was evident. The cats and dogs rushed
for egg-shells, whenever they came within their reach ; the squiiTel sci-aped off
the kalsomining from the wall so eagerly that its cage had to be removed
from the wall, though its food was that suitable for squirrels.

In a dog, in which osteomalacia had been induced, I produced a subcuta-
neous fracture of the leg-bones. When the animal was killed, seven weeks
after the fracture, the callus exhibited a marked cartilaginous new formation,
but with only a scanty deposition of lime-salts and very limited new formation
of bone near the injured bone-tissue. As in the above-named period the
fi-actured bones, of normal dogs invariably exhibited the formation of a
defined cancellous bone-callus, in the dog treated with lactic acid the forma-
tion of a bone-callus was obviously prevented.

As to the case of the seven months foetus, completely destitute of bones,
boni of a woman who for months during her pregnancy had fed the animals with
lactic acid, I wish to state that tliis woman must certainly have inhaled the
vapors of lactic acid, more particularly if pom-ed into the warm soup destined
for the animals. The woman was otherwise healthy, and remained so after
delivery; nevertheless, it must be mentioned that, several years pre^^ously,
she had given birth to a child which in early childhood was slightly rachitic.
The seven months foetus died of cerebral hemoiThage, which had CAidently
taken place dui-iug delivery, as the protecting skvdl-bones were absent.

2. INFLA3IMATI0N OF MuSCLE. TRICHINOSIS.

In 1868,* I published a series of observations and experiments
leading to the conclusion that the villi of the small intestine had,
at their points, perforations which opened directly into the cen-
tral lymph-vessel of the villus. The existence of these openings
could not, however, be positively proved. If these were really an
anatomical condition, we could easily understand how the embryo
trichina? are tran.sported from the cavity of the small intestine,
first into the chyliferous duct and afterward into the vascular
system. The trichinae could be carried with the blood, and fixed

* "Zur Kenntniss der Diinndarmzotten." Sitzungsber. d. Wiener Aka-
<lemie d. Wissensch., h-iii., Bd. 18G8.

26

402 INFLAMMATION.

as emboli iu the tissue of striped muscles, at the points where the
arteries merge into capillaries, which, owing to their rectangular
division (see page 274, fig. 117), would retain the worms. Muscles
which have a continuous motion and a markedly rectangular
division of their blood-vessels — f, i., the diaphragm — would be
the fii'st to be invaded by the parasites, while muscles without
this rectangular arrangement of the vessels — f. i., the heart —
w^ould not lie apt to become trichinosed.

The theory that the trichina embryos perforate the walls of
the intestine, and thence migrate into the muscles, is highly
improbable, as these parasites have no apparatus for perforating
tissues.

At the time before mentioned, I made in the Vienna Veterinary
School a number of experiments for the purpose of observing
trichime in the ehyliferous system of the intestine. I fed Guinea
pigs with fresh trichinosed muscle ; but these experiments proved
to be failures, as the animals became so rapidly affected after a
few days that all of them died, and I looked in vain for embryonal
trichinae in the villosities of their small intestines.

As soon as the embryos of trichinae reach the muscle an
inflammation of this tissue (myositis) sets in, which I have studied
in all its phases.

As to inflammatory changes of smooth muscle, we know,
through the researches of Dui*ante and others, that the spindles
divide into rows of inflammatory corpuscles, which at first retain
the general shape of the original muscle-spindles. Later, the cor-
puscles l)reak apart in the same way as those sprung from con-
nective tissue.

Inflammation of the striped muscles has, since IHol, often been
the subject of microscoi^ic researches. Some ol)servers have
asserted that only the nuclei of the muscle-fibers participate in
the inflammatory new formation ; others, that both the nuclei and
the contractile substance proliferate ; again, others have denied
any participation of nuclei or contractile substance, believing that
both perish, and that the whole inflammatory new formation is
due only to an emigration of colorless blood-corpuscles. Colberg
especially, in 1864 asserted that in trichinosed muscles an increase
of the nuclei occurs. Spina, one of the recent writers on the
inflammation of muscle, based his views upon researches made in
the frog's tongue, which he had artificially inflamed ; he claims
that the nuclei become much augmented, and that the contractile

I M' LA MM A riOX.

4():i

su])stanci' itself Itrciiks up into j)iis-c«ti-|)uscl<'s, jiiid that I'l'oiii solid
cjiky masses, the i)r()du<'t of the iutiaiucd iiiusclc tissue — red
bl()od-<'<)r])useles arise.*

The invasion of inusele-tissue is inunediately followed by an
inllannnatory process, visibU' lii'sl in the ])eriniysinin. (See Fi*;-.
169.) The perimysium becomes thickened and more or less
crowded with inflammatory cor-
puscles. The basis-su])stance is
liciuefied. the tissue reduced to
its juvenile condition, and the
newly appearing- medullary cor-
puscles by increase of their liv-
ing- matter become augmented
in the same manner in which
fibrous connective tissue in gen-
eral is affected by the infiamma-
tory process. (See page 356.)

The muscle-fibers in the ear-
liest stag-es of inflanimation are
unaltered, liut very soon a
marked chang-e takes })lace in
certain portions, depending
upon the location and number
of the parasites. The process
may attack single nniscle-fibers
in such a way that almost un-
changed fibers lie close to those
exhil)iting highly advanced al-
terations in their texture ; or
even a single fiber may be
normal in parts, and in parts Fig. 1G9.— Striped Muscle from

invaded bv the intlammatorv ™^ ^^^^ "^ ^ ^^^^' Recently

Invaded by Trichin.e.
process.

The fil-st noticeable change ''. t^cUiua in front view = .V, tiiclnna m sUU-

'^^ view. Jlaguified 200 tliameters.

consists in an enlargement of

the sarcous elements and a destruction of their regular arrange-
ment, together with the appearance of a larger number of bodies,
usuallv termed the nuclei of the muscle-fiber. These formations

* Arnold Spina. " Untersut'hungen iiber die entziindl. Vt'i-iinderunjjen d.
qnergestreiften Mnskelfasern." Wiener Metliz. Jalirbiieher, 187S. In tliis
essay a full account of the literature of this subject is found.

404 INF LA MM A TION.

being present in the middle of every muscle-fiber as well as at its
peripheiy, in both situations clusters of nuclei are found, some
of "vrhich have originated from former nuclei, while otliers are
newly formed. A di\'ision and niultiplicatiou of the nuclei is
infeiTcd from the fact that we frequently find clusters of nuclei,
exhibiting cleavage, or marks of division.

The next change is that, by an increase of the l)ioplasson of the
sareous elements, solid lumps arise, which in turn are split into a
reticulum and become nucleated, by the usual process of f onnation
of reticular fi'om solid bioplasson. Thus medullars' or inflamma-
tory coi-puscles become \'isible. arranged in clusters, which are
unquestionably identical with those embryonal formations from
which the striated muscle-tissue is developed. Instead of clus-
ters of medullar^' corpuscles, sometimes multinuclear bioplasson
masses are oliserved. These clusters are separated from each
other by rims broader than those between the single medullary
elements ; but all of these and all of the clusters remain uninter-
iniptedly connected by means of delicate bioplasson filaments
which traverse the interhiug light rims. (See Fig. 170.)

The clusters are arranged in rows, indicating that at fii-st the
sarcolemma remains unaltered. Afterward, however, it becomes
liquefied, and the inflammatory corpuscles .sprung from the
muscle-tissue commingle with those produced by the peri-
mysium, and in this manner more or less extensive masses of
inflammatory coi*puscles are formed, which are bounded by
relatively little changed muscle-fibers.

A second change of the muscle-tissue consists in an enormous
increase of the bioplasson of the sareous elements, which, by
confluence, produce irregular, caky, and globular masses of a
high degree of luster, apparently destitute of structure and closely
resembling fat. Former observers mistook these formations for
the result of a degenerative process. According to Spina's \'iew,
which is undoubtedly correct, they are the products of a progress-
ive inflammatory change of the contractile muscle-tissue.

These formations are not soluble in turpentine, therefore are
not fat ; they are readily stained with chloride of gold, but not
with carmine. Evidently, they are solid lumps of bioplasson in
a juvenile condition, which, in 1872, I termed '* htematoljlastic.''
From them originate, by di^^sion, a number of small solid parti-
cles, each of which gives rise to a new inflammatory element, or.
should the lumps break apart and become isolated, to red blood-
corpuscles. Such corpuscles are often found in clusters within

IXFLAMMATTOX.

405

the unl)n)kon sarcolciiunu slicath, vvliich ijlaiiily (Iciixmstrates
tliat tlu'y aiv not tlic result of heniorrliaj^e.

After the intlaniinatioii abates, the inedullaiv coi-puscles give
rise to a more or less extensive new foi-iiiation of coimeetive tis-
sue, eonstitutinji; a cicatrix in the middle of the iniisch'. Clusters
of medullary coi-ituscles may again ]>roeeed to the forming of

Fig. 170. — Inflammatory Changes op Muscle-tissue After Recent
Invasion of Trichina. From the Leg of a Man.

f^V, iuttami'd pei-iniysiuni : i', initial inflainniatory cliango of imiscle; /, liifrli "ilejrree of
iiitlaiiiniatory rliaiiKt"; I-. lioiiiojri'iicous caky, and F, gloltnlar, masses of solid bioplassou ; C,
capillary blood-vessel, with enlarged endotlielia. Magnified GOO diameters.

striated muscle-tissue, as was first maintained by C. O. Weber.
If, on the contrary, the filaments connecting the inflammatory
corpuscles break, pus-corpuscles will be produced, and by their

406

IXFLAMMA TIOX.

presence establi^<h an intramnseiilar abscess. I have observed
this result after ain{)utation of the tongnt-. for eaiieer. -with the
galvano-eautery.

The cicatrix may, under certain conditions, become trans-
formed into bone ; and regular bone-plates are sometimes met
^^ith in muscle-tissue, which, for a long: period of time, was
exposed to irritation.

If, fi'om the very beginning, the intianimatory process is con-
fined to the perimysium, a hypei-plasia of connective tissue will

ensue, which is often mistaken
for genuine hyperplasia of the
muscle-tissue itself.

In trichinosis, one of the re-
sults of the plastic inflamma-
tion is the formation of a hya-
line capsule around the parasite,
provided that the life of the
patient is suffieiently prolonged
for such a comparatively favor-
able termination. How the cap-
sule is formed I cannot say from
direct o>)servation. Id old cases
of trichinosis we find in the mid-
dle of the capsule one, sometimes
two, worms, coiled up with the
well-known two and a half turns,
shi-iveled and e\-idently saturat-
ed with lime-salts. (See Fig.
171.)

The space between the tri-
china and its capsule is filled
with a granular deposit of lime-
salts. Such depositions are fre-
quently met with at the poles of
the capside, and sometimes they
have a peculiar stratified appear-
ance. In the \icinity of an en-
cysted trichina we always find
cicatricial fibrous connective
tissue replacing the muscle fibers which were destroyed by the
former inflammatory process, and the cicatrix, as a rule, con-
tains a varying number of fat-globules.

Fig. 171. — Encysted Trichixa ix
THE Pectoral Muscle of a Max.

T, shriveled trichina, surrounded by a gran-
ular calcareous mass and inclosed by a hya-
line capsule, C; K. knob-like deposition of
lime-salts at one pole of tlie capsule; F, vacu-
oled fat -globules. Magnified 200 diameters.

IXFLAMMM IDS. 407

3. Inflammation of Nekvh-i'issli:.

liill;iiuiii;iti<»n of iicrvc-tissiu' is cliaractt'ri/cd by occiu-n'iices
very similar to those observed in inflammation of connective
tissue. ^Vll varieties of nerve-tissue — the jfray substance, tlie
ganglionic ek'ments, the meduHated and non-meduUated nerve-
fibers — first bi'eak down into mednnarv corpuscles, identical with
those which in embryonal development took ])art in the produc-
tion of nerve-tissue.

The first step of the inflammatory changes in nerves, as in
muscle-tissue, always starts in the supporting and accompanying
connective tissue, which, being the carrier of l)lo()d- vessels, reacts
most promptly to the irritation. Next follows the proliferation
of inflammatory corpuscles arising from the nervous tissue, and
the sum of tlie inflammatory new formation, so long as the
continuity of the c()ri)uscles remains unbroken, results in the
production of a dense, indistinctly fibrous connective tissue,
establishing the condition of sclerosis in the tissues of the nerve-
centers. Later, shrinkage of the newly formed connective tissue
causes retractions on the surface of the brain, which process H.
Kundrat terms poyeueephalitis.

Should the inflammatory corpuscles break apart in the early
stages of inflannnation, the result will be a complete destruction
of the tissue involved — /. p., the formation of an abscess. The
wall of the abscess, again, may be built up ])y newly formed
connective tissue. Such a combination of a formative and
destructive inflammatory process is well illustrated by the fol-
lowing article :

Microscopical Studies on Abscess of the Brain. By H. G.
Beyer, M. D., P. A. Surgeon U. S. Navy.*

The subject of my studies is a brain, the history of whieli is published in
the Transactions of the New York Patliological Society, vol. i., edited by
John C. Peters, M. D.

At a meeting of this society, held on January 13, 187.5, Dr. J. Lewis
Smith presented a specimen with the history, which is briefly as follows :

''Maggie, aged two years and six months, seemed in good health, was
plump and well developed. On the evening of December 5th, she ate her
supper as iisual, and was placed in her crib, apparently in perfect health. At
3 A. M. she was found in severe general ecclampsia. The general spasmodic

* "Journal of Nervous ami Mental Disease," July, 1880. The essay is here repnntert
in abstract. The term " protoplasm " is changed into that of " bioplasson."

408 INFLAMMA TIOX.

movements continued with more or less \'iolence till 1.30 P. M., and in the
muscles of the neck somewhat longer.

"At about 6 p. M., I found her lying quiet, rather stupid, but easily
aroused. Her vision was evidently good, and she was conscious : the pupils
responded to light, and the direction of the eyes was noi-mal; pulse 104 ; no
cough ; respiration and temperatui-e normal. There was no apparent loss of
motion of the muscles of the face, but the right arm and legs were paralyzed,
though the palsy was not complete. The great toe flexed on tickling the
sole of the foot, but the foot itself showed little or no motion ; but on attempt-
ing to flex the leg, which was extended, some rigidity of the muscles was
observed. At times, the patient produced slight movement of the thigh upon
the tinink. I think, during the two or three days succeeding the eon\-nlsions,
sensation in the right limbs was not entirely lost, though greatly enfeebled.
Subsequently paralysis in the right limbs, both of the nerves of sensation and
motion, became nearly or quite complete, and continued so until death.
Nevertheless, tickling of the sole of the foot caused some movements of the
great toe. On the left side, sensation and motion were perfect.

"December 9th. Has vomited to-day for fii-st time ; apparently sees well,
and the appearance of the eyes is nonual ; has no retraction of the head or
rigidity of the muscles of the neck, nor along the spine : pulse 96 ; tempera-
tui-e normal ; lies quiet with eyes shut ; is stupid and not particularly fretful
when aroused ; her bowels moved regularly.

"December 11th. Continued to vomit at intervals; pulse G8.

"December 16th. Pulse 80, temperature 100; vomited once yesterday,
not to-day ; lies in a constant doze.

" December 18th. Moans at times, as if in pain; pulse 180, temperature
100^ F.

"December 19th. Pulse 180, temperature 103°; there is convergent
strabismus, and her eyes have a wild, almost insane, look ; but she can see,
and grasped, huiTiedly, a percussion hammer presented towards her. Para-
lysis of nerves of motion and sensation in the right extremities nearly com-
plete ; slight movement could still be induced in the gi-eat toe by titillation ;
the vomiting has ceased ; tongue covered with a thick fur ; movements of the
bowels pretty regular; has a slight cough, such as is common in cerebral
disease.

" December 2 2d. Lies quietly on her side in perpetual slumber, with eyes
constantly shut ; pulse 118, temperature lOH"; the bowels still moved nearly
normally. The pupils, when exposed to the light, were seen to oscillate, but
are constantly more dilated than in health ; tlie urine passes freely. Has, at
intervals, circumscribed flushing of the features.

'■ December 24th. Pulse intermittent ; pupils dilated.

"December 25th. Died in profound stupor to-day, having lived nineteen
days from the commencement of the malady.

"Autopsy. On removing the calvarium and diu-a mater, which presented
no unusual appearance, the vessels of the pia mater were found rather more
injected than common. The cerebro-spinal fluid was scanty, and the surface
of the brain rather dry. The vertex of the left hemisphere was unusually
prominent, rising perhaps half an inch higher than that of the opposite side.
At the highest point, which was about one inch and a half from the median
line, was a circular yellowish spot upon the sui-face of the brain, about one
and a half inches in diameter. Pressure upon the spot, made lightly, com-

IXI'LAMMA 71 OX. 4()<)

inuiiicjitcd the scnsatidii of a larf^o oavity uiiiU'riieatli, filU-d witli licjuid,
anil ai>proacliiiiR to witliin two or three lines of tlie snrface. There waH no
adhesion or exudation at that jvoirit; and tlie surface of the brain appeareil
entirely noniuil, exeept sli-jht cloudiness of the piu mater at the base of the
brain, a little posterior to the optic commissure. The incised surface of tlie
brain, at a <listance from the abscess, showed no increase of vascularity. The
right hemisphere appeared in every way normal, except that its lateral ventri-
cle was tilled with pus, but not distended.

"On the left side, occupying the center of the hemisi)here, was an abscess
as large as the fist of a child of two years, extending from within two to three
lines of the vertex, where its site corresponded with the yellow spot on the
surface of the brain, to the roof of the lateral ventricle. Through this roof
the aliscess had V)iirst, filling and distending the ventricle with pus, and thence
making its way into the lateral ventricle of the I'ight hemisphere. The whole
amount of pus contained in the abscess and the two ventricles was perhaps
two ounces.

*' The walls of the left lateral ventricles were much softened, the upper
part of the corpus striatum and thalamus opticus being nearly diffluent.
The walls of the right lateral ventricle were slightly softened, but to a less
depth. The parietes of the abscess, which extended fi-om the roof of the
ventricle to the vertex, as already stated, were indiu-ated to the depth of one
and a half lines, except at the base of the abscess, which corresponded with
the roof of the ventricle, where softening had oecun'ed. The spinal cord, so
far as it could be examined from the cranial cavity, had the usual vascularity,
but was slightly softened.

"The cause of the encephalitis from which the abscess resulted was
obscure. The inflammation, so far as coidd be ascertained, was idiopathic.
There was no history of otitis, which is one of the most frequent causes of
cerebral abscess ; nor of heart disease so as to produce embolism. It seems
probable, since there was no fever till about the fom-th day after the convul-
sions, that an abscess had primarily occurred in the hemisphei-e between the
roof of the ventricle and the vertex — possibly some weeks previously. The
bursting of this into the lateral ventricle, and the constitutional disturbance,
inflammation, and softening to which these would ine\'itably give rise, affords
sufficient explanation of the history of the case, after the commencement of
the con\ndsions. "

The specimen was kept in a very dilute solution of chi'omic acid for several
months, after which time it was hardened in alcohol and iml)edded in a mix-
tui-e of paraffine and wax, whereby care was taken to enclose mainly the wall
of the abscess and its immediate sun-oundings. Previous to the beginning
of my studies, a certain number of sections had been made of the wall of
the abscess itself, as well as from other parts of the brain, such as the cere-
brum, the cerebellum, the medulla oblongata, and the gray matter. These
sections everywhere had been fomid holding a large number of so-called amy-
laceous corpuscles, exhibiting all the characteristic chemical and morpholog-
ical features of these formations. Xo other changes could be traced out,
nor did the blood-vessels show any anomalous conditions, excepting the capil-
laries, which were found dilated and choked with blood-corpuscles within the
inflammatory focus, as well as in its neighborhood.

I made a number of sections, both from the wall of the abscess and the
surrounding portion of the brain, which sections embraced the gray matter of

410 IXFLAMMATIOX.

the eorpiis striatum, thalamus opticus, the cortex of the left hemisphere, also
the white substance of the same, •which, as is e\'ident fi'om the history, was
the seat of the abscess. The specimens thus obtained were stained, partly
with an ammoniacal solution of carmine, partly, after thorough washing out
with distilled water, with a one-half per cent, solution of chloride of gold. The
different sections were mounted in glycerine, diluted with distilled water — this
method of mounting, as experience teaches, being far superior to the method
of movinting in Canada balsam or dammar varnish. "While glycerine-mounted
specimens, if taken fi-om properly hardened material, keep almost any length
of time, never losing their sharp and definite outlines of detail, Canada balsam
specimens, on the contrary, very soon become so transparent that their
minute details are completely lost to sight, and only the coarser formations
remain distinguishable. Canada balsam specimens, therefore, are fit for
lower powers of the microscope only; they are worthless for a power
exceeding 400 diameters, or for any power intended to give a display of the

^F

dfe-

FiG. 17i2. — AVall of A>r Absces.s of the Bkaix.
Transverse Section.

F, la}-ei- of fibrous connective tissne with .scanty blood-vessels, bounding the abscess ; M,
layer of myxomatous connective tissue, with numfi-ous capillary blood-vessels; TT, white
substance of tlie brain, witli numerous large blood-vessels. Magnified 200 diameters.

more minute anatomical featm-es. Oiu" lack of knowledge of the minute
pathological anatomy of the central nervous organization is mainly due to the
method of mounting in Canada balsam.

The subject of these investigations will be treated under the four follow-
ing heads, namely : Inflammatory changes of —

(1) Wall of abscess; (2) white substance; (3) non-medullated nerve-
fibers; (4) gray substance.

(1) Wall of Abscess. Transverse sections through the wall of the abscess,
which in different places varied in width from one to two millimeters, exhib-

iXFi.AMMA y/av.

411

- V

ited the followiiif^ chiinicteristic IVutmi'H. (See Fi^. 1 "'_'.) A layer of filjious
eoiineetive tissue forms the l)onn<larv of the abscess, its iiiiierrnost ])ortioii
preseiitiiifj a soiiiewliat jagf^etl appearaiiee, due to a imiiiber of attaclied jius-
<H>ri)uscl(>s. The bundU^s of eonneetive tissue in tliis situation were partly
infiltrated with, partly transformed into, })Us-eori)Uscles, and were arranpeil
in the shajje of rows, between whieh a scanty liasis-substance was tracealile.
In tlieir fjjeneral direction, tliese rows coi-responded to that of the Vjundles in
tlie subjacent tissue stratum, whicli was built up ])y dense l)undles of filn'ous
connective tissue in a more or less parallel course, and with itut few decus-
sations inclosing narrow, oV)long
spaces. These connective-tissue ^^^ -,,o

fibers held a large number of small : =" l-"-- '^-

spindle-shaped and a somewhat -^»— /

larger number of globular bioplas-
sou bodies, the former representing
what has been termed connective-
tissue corpuscles, the latter in-
flammatory elements. The meshes
between the bundles contained
granular layers of bi()])lasson,
with a number of intianimatory
elements, and also a moderate
amoimt of capillary blood-vessels.
In this layer, all stages of ncAvly
developing connective tissue could
be observed ; clusters of medullary
or inflammatory elements ; clus-
ters in whieh these elements had
already assumed an oblong or
spindle shape ; delicate spindles,
closely packed together and trans-
formed into basis-substance, wuth
a relatively small number of bio-
plasson bodies left.

Beneath the above described
layer of fibrous connective tissue,
the so-called membrana pyogena
of the older writers, there followed
a broad layer of connective tissue, exhibiting all the characteristics of the
variety termed myxomatous. The connective-tissue bundles, while dense in
the innermost layer, had become loose in the myxomatous portion, changing
to a more or less vertical course, and inclosing large meshes of a homogeneous
basis-substance. The coarser bundles formed strings, whieh by inosculating
with each other produced a reticulum, built up almost exclusively by spindle-
.shaped elements, partly transformed into basis-substance.

Within the meshes of this reticulum is contained a very delicate fibrous
connective tissue, with numerous, mainly spindle-shaped, bioplasson bodies;
large fields of the meshes hold an almost homogeneous or very slightly gi-an-
ular basis-substance. (See Fig. 17:3.) A number of capillary blood-vessels
of a considerable size, and partly filled with red blood-corpuscles, were also
met with. The endothelia of these capillaries were very large, and found

Fig. 173. — Wall of an Abscess, of the
Brain. Transverse Section.

/•', layer of librous conuective tissue ; T', iiests
of nHMlullarj' eleiuoiits, apparently produced by
the proliferation of the eiidotlieliaof former bloo<i-
v('S.>iel.s : M, luyxoinatovis poi-tioii, in the meslies
<if whicli numerous medullaiy elements are im-
lieddi-d, citlier in a delicate libious leticulum, or
in a li^bt, homogeneous basissulistance. llagui-
licd 500 diameters.

412

IXFLAMMA TIOX.

Al

to take up the carmine stain much more readily than endothelia under normal
conditions. Around the wreath formed by these endothelia, in many instances,
a light space was present, which space was enclosed by a collection of spin-
dle-shaped bodies — the perivascular sheath. Outside of this myxomatous
layer of connective tissue, in the wall of the abscess, is seen the white sub-
stance, boimding the layer of connective tissue in a very nearly straight line,
and considerably altered in structure, as will presently be described. In
addition to the above-described changes within the wall of the abscess, one of
the most striking phenomena exhibited in some of my specimens is the retro-

gi-ade movement of already newly formed
capillary blood-vessels into their embryonal
state — namely, the dissolution of their walls
y into medullary or embryonal or indifferent
elements, resulting in the formation of solid
connective-tissue bundles.

(2) White Substance. The white substance
around the abscess, as mentioned above, was
V in the condition of softening, and, even after
careful preservation of the specimen, difficult
to cut. With lower powers of the microscope,
in the immediate \iciuity of the abscess, the
capillary blood-vessels of the white substance
were seen to be considerably dilated and en-
gorged with blood-corpuscles. The perivas-
cular space, in many instances, was also
dilated, and filled with a finely granular, evi-
dently serous or albuminous, exudation. The
changes in the nerve-tissue were best marked
on the periphery of the blood-vessels. The
nerve-fibers had lost their myeline-sheath to
a considerable degi-ee, and their axis-cylind-
ers lay either bare or were surrounded by a
layer of a faintly reticular bioplasson, which
again was bounded by a thin homogeneous
or granular sheath. Owing to a want of di-
rect observation I am not enabled to tell
what I'eally had become of the myeline. It is, however, very probable that
during the initial stages of the inflammatory process the myeline is dissolved
out.

In many places the white substance was transformed into a finely granular
mass, in which bioplasson bodies, so-called medullary elements, could be
traced out, alternating with groups of shining homogeneous gi-anules and
relatively little changed nerve-fibers.

Higher powers of the microscope gave a complete series of the changes of
the axis-cylinders, which had led to the formation of medullary elements.
(See Fig. 174.) First, the axis-cylinders exhibited delicate nodular enlarge-
ments and, at certain in-egular intervals, a more regular rosary-like arrange-
ment. In certain districts the axis-cylinder was transfoi-med into a relatively
coarse, shining, beaded fiber, also pi-esenting a gi-eat many club-like enlarge-
ments. Next, some of the gi-anules alongside the axis-cylinders appeared
enlarged, and were provided with delicate vacuoles ; and, lastly, the axis-

FlG

1 74. — Axis - cylinders
from the bouxdart be-
TWEEN THE Gray and
White Substance.

-Ji, rosary-like, A^, elub-sliaped.
eulargement of the axis-cj-liniler :
A'i, medullary elements arisen from
the breaking apart of the axis-cylin-
iler : -V, nneleiisof the gr.iy substance
In proliferation ; T', vacuole. Magni-
fied 1200 diameters.

IMLAMMATIOX. 4i:i

vyliiulors witc traiisformed into a chain of pale l)ioj»lasson l)0(lics, tlio so-
called nu'dullaiy or iiillanimatorv elements.

Within the intlanuHl portion of the white substance were oljscrved nunier-
ons varicosities, eacii of which was in direct connection with an axis-cylinder.
In many instances, the interior of tiiese varicosities conld be made out to be
of a di'licate reticular structure ; they were invarialdy bounded l>y a dense
and homogeneous layer, continuous with the axis-cylinder. All the forma-
tions of the above description were uninterruptedly connected with each other
by extremely delicate threads.

lu some places small abscesses had formed outside the wall of the main
abscess; these abscesses were detected only with the microscope. lu such
localities the medullary elements had assumed a more uniform size, a some-
what coarser fn'anulation, and, ha\ing also lost their mutual connections, they
were transformed into pus-corpuscles. As a matter of course, that portion of
the white substance which had undergone such a change into pus-corpuscles
was devoid of blood-vessels. The manner in which blood-vessels are lost,
shortly before the tissues bi'eak down and are transformed into pus, was
easily traceable in the neighborhood of such small abscesses. The endothelia
of both the blood-vessel and the perivascular sheath became considerably
enlarged, coarsely granular, or w-ere supplied with at least several large
shining gi'anules, which might justifiably be considered as newly formed
nuclei. By a process of splitting of the enlarged endothelia into medullary
elements, the caliber of the blood-vessel, as well as of the perivascular
sheath, became obstructed, and thus, what formerly had been a capillary,
now was seen to have become transformed into a row of medullary elements.
These at first remained in connection with each other by means of delicate
processes, traversing the newly formed cement-substance, afterward broke
apart and became pus-corpuscles, in shape and size fully identical with those
sprung from other portions of the inflamed tissue.

The above-mentioned varicosities of the nerve-fibers, by ilifferent authors
are considered as post-mortem changes, and due to an irregixlar coagulation
of the myeline. The varicosities which I have described here have nothing
to do with myeline, but are formations of the axis-cylinders themselves, and
due to struetm-al changes in the substance of these axis-cylinders proper —
viz., enlargement of the thread, exhibiting the ordinary structure of bio-
plasson, and in close connection with the inflammatory changes of the nerve-
fibers in general.

These changes in the axis-cylinders can be understood only if we look
upon the latter as formations of living matter. In the inflammatory process,
the gi-anules of li^-ing matter in bioplasson bodies increase in size, some-
times to such an extent that the body is transformed into a shining, homo-
geneous lump, which readily divides into smaller particles, each of which in
turn may become a medullary element. The axis-cylinders, being formations
of living matter, also become coarsely granular, beaded, or rosary-like, and
each one of these granular enlargements may give rise to a new medullary
element, eventually a pus-corpuscle. In this manner we understand the
formation of rows of medullary elements and of pus in the middle of the
white substance of the brain.

Ever since J. Cohnheim asserted that the main, if not the only, soiu-ce of
inflammatory elements and pus-corpuscles are the emigi-ated colorless blood-
corpuscles, some authors had entu-ely overlooked the changes taking place

414 INFLAMMATION.

in th(> constituent elements of an inflamed tissiie. Nobody, nowadays, is
intendinfjj to deny the emigi'ation of eolorless blood-corpuscles from capillary
blood-vessels and small veins during the inflammatory process. Specimens
obtained from the brain under consideration, by the immediate transportation
of softened parts of the white and gray substance under the microscope,
plainly demonstrated the existence of such a process. Along the wall of an
enormously enlarged and engorged blood-vessel were seen colorless blood-
corpuscles of a club shape, with one blunt extremity still in the caliber of the
blood-vessel, with a thin pedicle still embedded in its wall, with the other
blunt extremity protruding outside the periphery of the blood-vessel. Not
infrequently a colorless blood-corpuscle was seen to be attached to the wall of
the vessel by means of a slender pedicle, the main mass of the corpuscle being
outside the wall of the blood-vessel or within the lumen of the perivascular
space. There cannot be any doubt that the emigrated colorless blood-cor-
puscles share in the formation of pus-corpuscles, yet I lay stress upon the
fact that the main source of inflammatory elements and pus-corpuscles must
be looked for in the living substance of the inflamed tissue itself. More espe-
cially in the white substance of the brain under consideration, all the stages
were traceable, fi-om the granular enlargement of the living matter of an axis-
cylinder up to the complete development and formation of inflammatory ele-
ments and pus-corpuscles therefrom.

(3) JVoii-mediiUafed Nerre-Jihcrs. A cei'tain portion of my specimens, which
was taken from the vicinity of the abscess, exhibited a large number of non-
medullated nerve-fibers in bundles cut longitudinally and transversely. In
the longitudinal bundles, the gray nerve-fibers were so closely packed together
that but a very faint striation could be traced out. In the midst of such bundles
there were numerous nests of medullary elements, of a prevailing oblong shape,
and independent of any blood-vessels. Ai-ound these nests the following
changes in the non-medullated nerve-fibers could be made out: First, the
nerve-fibers had assumed a beaded or rosary-like appearance ; next, they had
become spindle-shaped and coarsely granular ; after this, evidently fi-om an
increase in the size of the granules, the nerve-fibers had been transformed
into an oblong cluster of bioplasson, within which, through the formation of
a separating cement-substance, medullary elements made their appearance,
in clusters, still retaining their spindle shapes. Lastly, a number of such
spindle-shaped nests had coalesced, and rows and clusters of medullary ele-
ments could be seen, separated from each other only by a small niimber of
unchanged non-medullated nerve-fibers.

Wherever such a transformation of nerve-fibers into clusters of medullary
elements had taken place in a larger district, the result was the formation of
an inflammatory nest, in which the elements were connected with each other
by delicate threads. I have not seen an abscess in the middle of non-medul-
lated nerve-filiers, but it is obvious from what I said before, that through the
breaking apart of these medullary elements, as yet connected by delicate
threads, pus-corpuscles may arise.

I claim, basing myself upon direct observation, that inflammatory foci,
with ci'owded inflammatory elements, can arise from direct changes of the
bare axis-cylinders constituting non-medullated nerve-fibers, independently
of either blood-vessels or emigration of colorless blood-corpuscles.

(4) (irai/ SubHtancc. In the vicinity of the abscess of the brain, I have met
with a number of changes in the gray substance. First, the points of inter-

JM'J.AMMA'JJOX. 415

soi'tidii of tlu' living:; matter were I'liliirf^inl, wluTflVuiii resulteil a coarse
gi'amilation of the gray substance. In many places, with the liighest powers
of the microscope, the points of intersection of the reticulum were clustered
together to such an extent that lightly grmiular, nearly homogeneous, groups
appeared, each of which was surrounded by a light rim. Owing to an aug-
mented afflux of nourishing nniterial, the formations of living matter had
evidently very nnicii increased in size, and by ajiproaching each other pro-
duced densely granular or homogeneous lumps of living matter, with the
appearance of indilferent or medullary elements. In certain places, the whole
mass of the gray substance had been transformed into such medullary cor-
puscles, between which bundles of non-meduUated nervc-tibers and blood-
vessels, mainly capillary in nature, were still recognizable.

The nerve-fibers traversing the gray substance were mostly increased in
size, and transformed into beaded fibers or chains of small homogeneous
lumps. The blood-vessels, besides being completely obstructed with red
blood-eorpuscles, exliibited changes in their endothelial walls identical with
those described above in connection with the white substance.

The nuclei of the gray substance were mostly very coarsely granular; the
nucleoli especially had increased in size, and looked as if split up into a num-
ber of coarse granules. More ^specially in the carmine-stained specimens I
often observed larger spaces, identical with the periganglionie space, either
empty or holding extremely delicate granules. These si)aees, so-called vacuoles,
very probably had formed by an aecumidation of a serous exudation around
the nuclei, by which either a certain amount of the surrounding gray substance
was pushed in a peripheral dii'ection, or a certain amount of li^ang matter
destroyed. The tine granides within the above spaces, consequently, were
either coagulated albumen or remnants of the former reticulum of living
matter.

New formation of nuclei in the inflamed gi'ay substance is of very common
occurrence. Within the spaces just described I sometimes saw one large and
two or three small nuclei, which, being in contact with their flattened sur-
faces, looking toward each other, allow of the conclusion that they had origi-
nated by a process of division of the original single nucleus.

New formation of nuclei, doubtless, takes place independently of former
nuclei in the gray substance. I have seen repeatedly clusters of bioplassou
near the wall of the abscess, with irregular outlines and holding a large num-
ber of oblong nuclei. Such multi-nuclear masses are evidently produced by
the confluence of bioplassou bodies (emigrated colorless corpuscles — Ziegler),
or by the formation of territories previous to their division into inflammatory
elements.

The ganglionic elements within the inflamed brain-tissue exhibit a series
of changes of great interest. Nearest to the abscess a number of ganglionic
elements had swelled and been transformed into almost homogeneous, indis-
tinctly gi'anular bodies, still characterized by the presence of offshoots and a
ileep carmine stain. No doubt, the swelling of these elements is due to an
inundation with exudation, which leads to a stretching and breaking apart
of the reticuhmi of li\ing matter therein.

The capillaries of regions where such swelled ganglionic elements are
nimierous are considerably dilated, their endothelial coat is partly thinned,
partly thickened, by endogenous new growth, and their perivascular sheath
enormously widened. In this space I have seen faint granules and pale gran-

416

INFLAMMA TION.

iilar bioplasson bodies of the size of colorless blood-corpuscles, indicating that
immigration of such corpuscles had taken place.

In other portions of the gray substance a marked proliferation of the gang-
lionic bodies can be observed. There are bodies with enlarged and beaded
nucleoli, bodies with two or three isolated nucleoli, bodies with two or three
coarsely granular nuclei, sprung from a division of the original nucleus, as is
proved by the presence of facets, where the nuclei lay against one another.
(See Fig. 175.) Many ganglionic elements are transformed into coarsely
granular, nearly homogeneous, lumps, and split into smaller lumps, varying in

number from two to seven or eight.

J

-i-l^.

>G3

Gl-

■h:

The clusters of bioplasson bodies
are grouped together in such a way
as to retain the general shape of
the ganglionic body, considerably
enlarged. The offshoots of these
elements are in many instances
still recognizable as being either
enlarged and coarsely gi'anular or
broken apart into rows of bioplas-
son bodies.

As to the origin of medullary

elements within the ganglionic

bodies, I can state positively that

d.-i .-ft JW'Jh^i * i iijpy iiave originated by a process

Fig. 175.— Inflammatory Changes of of endogenous gi-owth fi-om the

THE Ganglionic Elements of the bioplasson of the ganglionic bodies

Gray Substance of the Brain. themselves. First, the living mat-

, , ,•»,,, ter was increased, hence we explain

(?i, coarse granules ana new mulei in tlie bodj' ' '■

of the ganglionic element ; ai, .si>iittiug of tiie the coarsely granular and homo-

ganglionic element on its periplunal portion ; G^, geneous looks of such an element ;

the whole body transformed into meitullary ele- ^^^^^^ ^^^^^^ ^j division had formed

by the division of living matter into
angular himps, closely packed to-
gether so as to flatten each other, and separated by a thin layer of fluid, which
everywhere was traversed by delicate conical offshoots, uninterruptedly con-
necting all newly formed lumps with each other. Some of these lumps,
apparently, had further advanced in development than others ; while some
looked still shining and homogeneous, others were already coarsely granular,
and presented a marked formation of a nucleus and a nucleolus. Again, all
these formations, gi-antUes, nucleolus, and inclosing shells are united by
delicate threads.

Lastly, the whole ganglionic element and its offshoots had broken apart
into medullary or indifferent corpuscles, which, so long as they remain united
to one another by delicate threads of living matter, represent an indifferent,
medullary, or inflammatory tissue, identical with that arisen from the gi"ay and
white substance of the brain. If, on the contrary, the tmiting offshoots be
torn, the isolated medullary elements will produce pus-corpuscles, and an
accumulation of such corpuscles gives rise to what is called an abscess. In
the pus taken from the abscess of the brain under consideration, besides pus-
corpuscles, a large number of bioplasson bodies were found suspended in
the fluid, in size considerably exceeding that of ordinary pus-corpuscles.

/iA|4%;.^'^'>-

ments : A, axis-cylinder exliiliitiii
change. Magnified 600 diameters.

IN FLA MM A TION. 417

These large bodies exhibited all stages of endogenous formations and prolif-
erations of living matter, sufficiently indicating their origin from the gang-
lionic elements of the gi'ay substance of the brain.

The lUrraiure on the subject of my studies is extremely sterile. No exact
observations, at least to my knowledge, have as yet been made on acute
encephalitis and suppuration of the brain substance. Only one point has so
far been called attention to, and this is the proliferation of the ganglionic
bodies of the gray substance. Th. Meynert * first noticed a proliferation of
the nucleoli and nuclei of ganglion elements. E. Fleischl t found a division of
ganglioTiic bodies, though not in a strictly inflammatory process, but in a brain
involved in the formation of a tumor. A. R. Robinson t produced inflamma-
tion in the ganglia of the sjinpatlietic nerve around the aorta of the frog, and
observed a division of the ganglionic elements fi-om the formation of a furrow
on the surface to the complete division into small particles. The di\asion
may involve only a part of a ganglionic body, the rest remaining normal, or it
may invade the whole. Analogous transformations were also observed in the
elongations of the ganglion cells.

Andrea Cecchirelli $ produced traumatic lesions in the large hemispheres of
the brain of a chicken and of rabbits. He saw enlarged and granular "gang-
lion cells " within the inflammatory focus, and came to the conclusion that the
nuclei had increased in number and that the whole " ganglion cell," by divi-
sion, had been transformed into smaller elements.

The results of my own observations can be summed up in the foUo-wdng
points :

(1) The gi'ay substance of the brain, by the inflammatory process, is trans-
formed into inflammatory or medullary elements, in the production of which the
nuclei and ganglionic bodies also share. Non-medullated nerve-fibers, through
an increase of living matter in the axis-cylinders, are likewise transformed into
medullary elements. The same results are produced in inflammation of the
white substance of the brain, after the dissolution of the myeline.

(2) The medullary elements, sprung from the gray or the white substance
of the brain, are transformed into connective tissue, either myxomatous or
fibrous, and thus the wall of an abscess in the brain is the result of the reduc-
tion of the brain tissue first into medullary corpuscles, next into myxoma-
tous, and lastly into fibrous connective tissue.

(3) Medullary elements, irrespective of which particular nerve-element
they had originated, when broken apart, constitute pus-corpuscles, and,
therefore, the contents of an abscess of the brain. In the fluid of the abscess
clusters of bioplasson bodies are seen, proving a transformation of ganglionic
elements into pus-corpuscles by a process of endogenous new formation and
subsequent division of living matter. All the stages of this process are
observable witliin the ganglionic bodies of the inflamed gray substance itself.

(4) The endothelia of the blood-vessels become enlarged, coarsely granu-
lar, and proliferating in the process of inflammation of the brain-tissue. New
blood-vessels are formed in the wall of the abscess. A consolidation of the

* " Vierteljalirsclirift fur Psychiatrie," 1867.

1 "Meil. Jahrbiicher," 1872.

t " Ueber die eutziindliclien Veraiiderungen der Ganglionzellen des Sympathicus," Med.
Jahrbiicher, 1873.

i " Ein Beitrag zur Kenntuiss der eutziimllicheu VerauderiinKeQ des Gehirnes," Med.
Jahrbucher, 1874.

27

418 INFLAMMATION.

blood-vessels, on the contrary, and a breaking up of their endothelia into
medullary elements, afterward pus-corpuscles, takes place whenever the
tissue is destroyed by suppuration. Pus is mainly a product of the inflamed
tissue itself, and not of emigi'ation of colorless blood-corpuscles.

4. Inflajvimation of Epithelia and Endothelia.

Epithelia and endothelia, being formations of living matter,
respond in a very active manner to irritation. The changes of
this tissue are not primary, as the inflammation invariably starts
from the subjacent vascularized connective tissue. Even in mild
cases of inflammation in connective tissue, the presence of an
exudate can be demonstrated, which constitutes the condition
known as " oedema." The surplus nourishing material is carried
into the epithelia and endothelia from the blood-vessels, even
though the irritating agent should be brought in direct contact
with the epithelial or endothelial investment.

The inflammatory changes in this tissue, as in every other,
consist in an increase of the living matter ; the elements become
what is termed " coarsely granular," or assume the " condition of
cloudy swelling." If the inclosing shell of cement-substance is
not immediately liquefied, a marked endogenous new formation of
corpuscles takes place, resulting in the appearance of the so-called
"mother cells" — /. e., bioplasson bodies, containing a varying
number of inflammatory elements, in all stages of development.
We can trace the new formation of these elements from the coarse
granides to the large homogeneous lumps, and, finally, to the
nucleated plastids (see page 46). If, on the contrary, the cement-
substance is liquefied in the early stages of inflammation, the
living matter herein present — /. e., the connecting filaments
("thorns") — is enlarged, and shares in the new formation in
•the same manner, as observed within the epithelial or endothelial
elements. First, a number of these elements coalesce, and form
large clusters of bioplasson, containing a varying number of
nuclei and a large quantity of coarse granules, which, passing
through the phases of bioplasson development, result in the
production of inflammatory corpuscles. The final Result of the
inflammation is different, according to the i)lastic or formative^
or the suppurative nature of the inflammatory process.

In plastic inflammation, the newly formed medullary or in-
flammatory corpuscles remain interconnected, and, becoming
fusiform, give rise to new formation of connective tissue. The " ciiT-

INFLAMMATION.

419

hotic" ooiiditi<ni of the kidneys and the liver, f. i., is eaiised
by the trjiust'ornuitiou of the cpithelia into connective tissue,
throufjli the intermediate stage of medullary tissue. In suppura-
tive infiainniation, on the contrary, the conntM-iion of tin; medul-
lary elements, which ((riginatcd in the enlarged ei)ith('lia and
endothelia, is broken, and the medullary plastids, now termed
pus-corpuscles, arc freed either by active emigration or by the
contraction of the bioplasson of the parent body, which remains

Fig. 176. — Beginning of the Pustular Stage in H/Emorrhagic

feMALL-POX.

n, formation of liomogeneoiis lumps from the bioplasson of tlie cuboidal epitUelia ; E,
lioiiiogeueoiis and vacnoled lumps suspenilt'd in a finely granular, albumiuons lifiuid. C (left),
ledges of former cement-suV)stance, tlio bioplasson of wliicli lias considerably increased in
bulk; C (riglif), deepest layers of epitlielia, compressed and rendered spindle-sliaped, also
■with commencing increase of bioplasson. O, papillary layer, flattened and in the condition of
oedematous swelling. Magnified 600 diameters.

comparatively little changed. The parent body itself, after the
evacuation of the pus-corpuscles, presents a fenestrated appear-
ance, with a varying number of vacuoles, indicating the location
of the pus-corpuscles, or an apparently empty shell, pierced by
delicate septa. All these formations are easily traced in the
vesicvilar and pustular stages of small-pox. (See Fig. 176.)

Surface epithelia, if present in a single layer, are readily cast

420 INFLAMMATION.

off from the underlying membraneous connective tissue, and in
the secretions are found to exhibit different degrees of an endo-
genous new formation of bioplasson. In the case of stratified
epithelia, the outermost are shed off without marked changes,
their bioplasson being lost in a horny metamorphosis. Some-
times the nuclei in these epithelia are seen to be homogeneous
or coarsely granular, indicating that these formations are still
endowed with a certain degree of vitality. The cuboidal epithelia
of the middle, and the columnar epithelia of the deepest, layer
show, in the most marked manner, the inflammatory changes
described above.

Whether or not lost epithelia can be replaced by a new forma-
tion arising from the subjacent connective tissue is still an unset-
tled question, notwithstanding the numerous experiments which
have been made. It is also unknown how the new formation of
epithelia proceeds from former epithelia, although it probably
takes place in the same manner, as will be described later on, in
the article by L. Elsberg on papilloma — viz., from wedge-shaped
bioplasson masses, springing from coalescence and growth of
the inter-epithelial connecting filaments ("prickles"), imbedded
in the cement-substance. That such a new formation is
actually and rapidly going on is illustrated by the catarrhal
inflammation of mucous membranes, in which great quantities of
epithelia are lost, and again replaced after the inflammation has
subsided. The cast-off epithelia of single layers are probably
never completely restored.

A third series of changes of epithelia is observed in fibrinous
or croupous inflammation. Here the epithelia are imbedded in,
and saturated with, the exudate, and are either completely
destroyed or only their nuclei are left. Such a destruction of epi-
thelia takes place in the croupous inflammation of mucous mem-
branes (Wagner) and in the croupous inflammation of the kidneys.
The production of tubular casts in the latter disease is largely
due to a degenerative metamorphosis of the epithelial elements
of the uriniferous tubules.

Cornil and Ranvier were the first who maintained that in
inflammation the endothelia are enlarged, and their nuclei divide
and become the source from which pus-corpuscles are formed.
The inflammatory changes of the endothelia of the peritoneum
(omentum) have been studied most accurately by H. Kundrat.
He noticed first a loss of the cement-substance, in place of which
scattered globular bodies were seen. Next, enlargement and

TXFJ.. I MM. 1 TTON. 421

division of the nucleoli and the inidci of the cndotholia followed.
In recent peritonitis he found hxr^a niultinuclear bodies, which
greatly surpassed in size single endothelia, and in purulent peri-
tonitis a nnirked new formation of inflHiiHnatorv<'orpuscles, aris-
ing from the endothelia and leading to the formation of pus-
corpuscles ; but, probably, not all of these corpuscles are offspring
of endothelia, Knndrat was the first to maintain that from the
endothelia of the peritoneum, in chronic, plastic peritcmitis, con-
nective tissue arises, which leads to the formation of vegetations;
and that this process takes place in two ways : either the endo-
thelia themselves become spindle-shaped, elongated, and trans-
formed into fibrilla?, or uniformly nucleated proto|)lasmic layers,
sprung from the endotlielia, become directly fibiillated.

The inflammatory changes of the endotlielia of hlood-vessels
were studied by Virchow, Waldeyer, Ranvier, Thiersch, Durante,
and others. Swelling of the endothelia, division of their nuclei,
and new formation of inflammatory corpuscles from endothelia,
have been proved to occur beyond any doubt. By some observers
a direct transformation of endotlielia into connective tissue is
maintained. The occlusion of ligated vessels is mainly due to a
proliferation of the innermost endothelia, and the vascidarization
of the thrombus is proved to start in the inflamed intima, and to
proceed also from the adventitia and media. This is contrary to
the views of C. O. Weber, who held that the coagulated blood of
the thrombus itself becomes organized and vascidarized. The
coagulation of the blood was found to be caused by the inflam-
mation of the endothelia.

In the foregoing article on encephalitis, by Beyer, repeated
allusion is made to the inflammatory changes, both progressive
and regressive, that take place in the endothelia of capillaries.
From what I have observed, I can confidently state that the endo-
thelia of the capillaries participate in the inflammatory process
in a very active manner. In the earliest stages of inflammation
the endothelia l)ecome at fii-st enlarged and coarsely granidar, in
consequence of which the caliber of the vessel is considerably
narrowed. Next, the endothelia enter the juvenile stage of bio-
plasson by becoming homogeneous, and through their confluence
render the formerly hollow bioplasson a solid, homogeneous cord,
in which afterward a differentiation into medullary or inflamma-
tory corpuscles takes place. Such corpuscles may sometimes
spring directly from the capillary endothelia, without previous
solidification of the blood-vessel. The result is, that in acuteinflam-

422 INFLAMMA TION.

mation a large number of capUlary blood-vessels are destroyed — /. e.,
transformed into the inflammatory new formation. Should the
inflammatory corpuscles separate and produce pus, a permanent
destruction of the vessels ensues. If, on the contrary, the in-
flammation should not pass the stage of tissue-formation, — /. e.,
become plastic and formative, — an active new formation of blood-
vessels in the middle of the inflamed tissue will follow, independ-
ently of the former and older blood-vessels, and to an extent far
exceeding the former vascularity. Most of these newly formed
blood-vessels contain newly formed red blood-corpuscles. The
manner of new formation of blood and blood-vessels is dwelt
upon on page 373. Should new formation of blood-vessels in an
inflamed tissue not take place, the tissue will represent what is
termed a " tubercle," and undergo different secondary changes.

The endogenous new formation of elements within the epi-
thelia was fii-st maintained by Remak in physiological, and after-
ward by Buhl, Rindfleisch, and others in pathological, conditions,
and its existence thoroughly proved by L. Oser. In opposition
to the view that the corpuscles \'isible in the endothelia had
immigrated from without, Oser demonstrated the origin of in-
flammatory corpuscles u-itJiin the epithelia. My own researches
fullv corroborate the statements of Oser.

Varieties of Ixfla^oiatiox.

From my statements it follows that I consider the presence of
blood-vessels to be a requisite for the production of an inflam-
matory process. As only connective tissue is supplied with
blood-vessels, it necessarily follows that the primary seat of
inflammation must always be in the connective tissue, and that
the structural changes of muscles, nerv^es, and epithelia are sec-
ondary to, though, perhaps, almost simultaneous with, those of
the connective tissue. An independent inflammation of epithelia
never occurs. I, therefore, consider the terms of '' interstitial,"
" parenchymatous," etc., inflammation as superfluous, except for
clinical purposes.

Emigration of colorless blood-corpuscles unquestionably oc-
curs, even in the earliest stages of inflammation, probably pre-
ceding structural tissue changes. Such an emigration may also
participate in the formation of pus-corpuscles, so long as the
blood-vessels are not destroyed. The principal change, however,

IN FLA MM A TION. 423

moro ])arti(Milarly ('(mccnis the invaded tissues themselves. They
are tirst reduee<l to their juvenih' eondition; their niedulhiry
elements, by endogenous or exogenous new formation or simple
division, give rise to a new formation of inflaiimiatorv <*or])US-
cles. If these remain inter<M)nneeted, a new foi'iiiation of tissues,
in most instances, and most predominantly of connective tissue,
takes place; thus, "lnq)ertropliy" or "hyperplasia" is estab-
lished. If, on the contrary, the intlammatorv corpuscles become
separated, pus-corpuscles arise from the inHamed tissue, either
forming an abscess or leading to pyoiThoea or empyema. The
question, how many of the pus-corpuscles owe their origin to
emigration of colorless blood-corpuscles, cannot be answered
positively.

Considering both the nature of the exudation and the tissue
changes, there is no good reason to abandon the old terminology
of '* humoral pathology " for the designation of different forms of
inflammation — such as catarrhal, croupous, etc. These, it is true,
differ only in degi'ee, but the names, having been once adopted,
may be used, as heretofore.

(a) Catarrhal injiammation consists of a serous exudation, a
partial reduction of the connective tissue into its juvenile con-
dition, an increased secretion, proliferation, and shedding of the
epithelia. In acute catarrhal inHammat'ton the predominant feat-
ures are the serous exudation, the augmented secretion, and shed-
ding of the epithelia from the free surfaces and in glandidar
organs ; there is, in addition, a h^-peraemia of the subjacent con-
nective tissue. In siihacute or chronic catarrhal inHammation the
augmented secretion and shedding of the epithelia persists, and
the subjacent connective tissue is hypertrophied, with a more or
less new formation of blood-vessels, or, on the contrary, reduced
in bulk — atrophy. In closed or occluded glandular cavities the
epithelia are transformed into medullary corpuscles, from which
new connective tissue arises — cirrhosis.

(h) Croupous inflammation consists of a fibrinous exudation
and a partial reduction of the connective tissue into its juvenile
condition, while the epithelia, by their imbibition of the fibrinous
exudate, are destroyed. In acute croupous inflammation the exu-
date is sometimes fibrinous, sometimes modified albuminous. On
free mucous surfaces and in glandular organs the epithelia are
destroyed ; these, with intense hyperaemia, ha?morrhage, and
inflammation of the connective tissue, are the main sjTuptoms.
In subacute or chronic croupous inflammation the exudation is

424 INFLAMMA TION.

modified, often containing the so-called colloid or waxy material.
The subjacent tissue is hj^ertrophied, and, in certain districts,
the epithelia are completely destroyed and a profuse new forma-
tion of fibrous connective tissue is produced. This condition is
called atrophy.

Diphtheritic inflammation consists of a fibrinous exudate in the substance of
the connective tissue, with an isolation of portions of this tissue, and their
subsequent death — viz. : putrefaction and throwing off of the so-called mem-
brane. Organisms of decomposition, micrococci and bacteria, are secondary
products of putrefaction. For a long time the difference between croupous
and diphtheritic inflammation was held to be that in the former the exudate
forms on the surface, in the latter in the substance of the tissue itself ; but
they are, in essential points, identical processes.

fcj Suppurative inflammation consists of an albuminous exu-
dation, a complete breaking down of the connective, muscle-, or
nerve-tissues, and of all blood-vessels, into pus-corpiiscles, also a
new formation of these corpuscles from epithelia. Acute suppur-
ative inflammation results in the formation of an abscess in the
middle of the tissue, or a flow of pus from free surfaces, — the
so-called pyorrhoea, or an accumulation of pus in closed cavities
— the so-called empyema. Blennorrhoea and intense catarrhal
inflammation blend with suppuration, and may be either acute or
chronic. Chronic suppurative inflammation is characterized by
intense hyperplasia of the connective tissue, together with per-
sistent augmented secretion and a partial destruction of blood-
vessels and tissues — the ulceration.

The healing process of wounds by suppuration is accompanied by an
active outgrowth of fi-eely vascularized, newly formed, connective tissue,
which is at first of the myxomatous variety, and is tei'med granulation tissue.
How much pus is produced by emigration of colorless blood-corpuscles in
blennorrhoea, pyorrhoea, and in healing and granulating wounds, we are
unable to say. The originally myxomatoiis tissue of gi-anulating wounds is
changed into fibrous connective tissue ; the at first numerous blood-vessels
are, to a great extent, also transformed into fibrous tissue, and these processes
terminate finally in a scar, cicatrix.

If the inflammatory new formation be not supplied with newly formed
blood-vessels it is called a tubercle, and the totality of the avascular new
formation represents the tuberculous mass, which, by the breaking and the
shi'iukage of the inflammatory corpuscles, becomes "cheesy." Tubercle,
therefore, with some reason, may be termed a dry abscess.

No allusion is made in this chapter to the parasitic origin of the inflam-
matory process, especially the germ theory, as applied to inflammation.
Unquestionably, organisms of decomposition, if brought into the interior of
a living tissue, or, perhaps, even only in contact with it, will excite inflamma-

INFLA MM A TION. 425

tion or necrosis. But how much is true of tlie " specificity " of siidi lf)w orf^aii-
isins, us rcf^artls inahirial fever, recurrent fever, typlioid fever, sypliilis, leprosy,
diplitheria, etc., is a question wliicli to-ilaj' cannot bo positively answered, as
the sources of mistake, both in experimental and microscopical researcli, are
too numy and too little under our control. What the infecting germs of
measles, scarlet-fever, and small-pox are, we do not know.

/Sccondarj/ CJtduges. Among- the disturbances of nutrition,
partly considered as inflammatory, partly unknown in their
orio-in, tliree deserve mentionino- — namely, the fatty, the pig-
mentary, and the waxy degeneration.

Fatti/ Degeneration. As mentioned before (see page 155), the
fat-granules are directly produced from granules of bioplasson.
Every living tissue, in a physiological or pathological process,
may exhibit fat-granules, both in its free bioplasson bodies and
in the interstitial substances. In this latter situation, also, the
fat originates from the bioplasson formations. In the myxoma-
tous and fibrous variety of connective tissue the fat is a normal
product, at least to a certain degree ; cartilage corpuscles often
exhibit fat gi^anules and globules, even in middle-aged individ-
uals. In chronic inflammation of cartilage and bone, especially
in their ulcerative destruction, in caries, fat-granules are very
common occurrences in the plastids. In muscles, fat- granules
arise from a direct transformation of the sarcous elements : in
paralyzed and atrophied muscles, from want of exercise; in
typhoid fever ; in the muscle of the heart, either as an independ-
ent pathological process, or in connection with hypertrophy. In
higher degrees of fatty degeneration of the muscle of the heart,
nearly the whole organ, but principally the left ventricular
wall assumes a yellow color, and the tissue becomes quite brit-
tle. Most of the sarcous elements have been converted into
fat-granules, which slightly exceed the original sarcous elements
in size ; they still remain interconnected, however, by delicate
filaments. In the ganglionic elements of nerve-tissue, fat-gran-
ules are often met with ; this always indicates a disturbance in
the intellectual, sensitive, or motor centers. I have seen fatty
degeneration of the axis-cylinders of nerves, resected for the
relief of neuralgia, caused by the so-called perineuritis — /. e.,
chronic inflammation of the external and internal perineurium.
In epithelia and endothelia fatty degeneration also occurs, reach-
ing its highest degree in the epithelia of the liver. Wedl has
demonstrated fatty degeneration even in the cement-substance
of epithelia perfectly healthy. A rare and sometimes intra-

426

IXFLAMMA TION.

uterine process is the fatty and pigmentary degeneration of the
covering endothelia of the heart, probably caused by pericarditis.
(See Fig. 177.)

Tissues in fatty degeneration are often subject to ealcareoiis
depositions, both processes being indicative of a lowered nutri-
tion of the bioplasson, the causes of which are not clearly under-
stood.

Figituittari/ degeneration is closely allied to fatty degeneration.
Even under normal conditions fat-globules may contain a diffuse

or granidar coloring matter, and
fatty and pigment degenerations
are often found combined. We
have no chemical analysis of the
pigment ; but its source is un-
questionably the coloring matter
of the blood. Extravasated blood,
after a while, produces rhomboidal
or needle-shaped crystals of hfema-
toidine, which are in color dark
reddish-brown. (See chapter on
imne.) If the coloring matter be
imbibed by li\dng plastids, pig-
ment-gTanules of a rust-brown or
brownish black color will be seen
in these bodies. The rusty color
of the tissue, sometimes seen
abounding in old, healed apo-
plectic focus in the brain, is due
to the presence of pigment-gi*an-
ules. Rokitansky maintained, in
1846, that in melanotic cancer the
pigment is supplied by the blood,
which originates in the mother
cells. My own researches, made
especially in the boundaries of
melanotic myeloma of the choroid invading the vitreous body,
demonstrate that the soiirces of the j)igment are the hfemato-
blasts — i. e., lumps of li\dng matter, saturated with coloring
matter (haemoglobin ?) of the blood. The points of intersection
of the bioplasson reticulum within these x^lastids are enlarged, and
assume a dark yellow or l)rown tint, remaining, however, in con-
nection mth the reticulum. By coalescence of the granules pig-

FiG. 177. — Fatty and Pigment-
ary Degeneration' of the
Pericardial Exdothelicm of
THE Hearit of a Child.

F, enilothelia, exhibiting tlie begin-
ning of fatty change of tlie granules of
bioplasson ; -P, endothelia, with pigment
granules In their interior. Magnified 600
diameters.

INFLAMMATION. 427

iiient-clusters orifrinate. whioh may still remain connected with
the unchanged biojthisson ; and if the j^ranules are present in large
numbers they may conceal the nucleus of the plastid, which, as a
rule, both in physiological and pathological pigment formations,
remains unchanged. (See Fig. 177.) All varieties of tissues may
become the seat of ])igmentary degeneration, and it is evident, par-
ticularly in melanotic cancer, that both the connective tissue and
the newly formed epithelial plastids are more or less abundantly
supplied with granules and clusters of coloring matter. Rust-
brown pigmentation is sometimes observed in the sarcous elements
of striated muscles, in the gray substance, and the ganglionic cor-
puscles of the nei'\'e-centers, independently of former haemoiThage.
The fact that it is the li\dng matter itself which is transformed
into pigment, facilitates the understanding of the very rapid
disappearance of pigment — f. i., from the epithelia of the skin
and the medullary tissue of the hair-bulb.

Waxy der/enerdfion. In chronic ailments, such as syphilis, pro-
fuse suppuration, caries of bone, etc., and in the placenta even in
apparently healthy women, a peculiar change of the tissues, called
waxy, takes place, which leads to an increase of bidk, a pahng of
theii' color, due to compression and obhteration of blood-vessels,
and an increase of weight and consistence. There is a general
appearance of the tissue similar to that of wax or lard ; hence the
term "■ lardaceous," which is also used to designate this change.
Unquestionably, this degeneration is due to a chemical change of
the plasma of blood, as it is sometimes found in haemoiThagic
clots, independent of, or combined with, analogous tissue changes.
What this change really consists in we do not know, and it is a
mere h\'pothesis of Dickinson's to call the waxy substance " de-
alkalized fibrine."

The appearance of waxy degeneration varies in different
tissues and organs. The chemical reactions are not always
the same ; neither are the stainings with carmine and ani-
line colors always productive of the same results. The myxom-
atous variety of connective tissue is not infrequently the seat
of waxy degeneration. (See article on waxj' degeneration of
the placenta.) In certain diseases the medullary tissue of
bone is invaded by this change, which leads to the formation
of globules termed '' coUoid corpuscles," which are remarkably
unresponsive to the usually destructive action of acids and alka-
lies. (See article on osteomalacia.) In the m\^omatous tissue
of the thymus body such homogeneous or concentrically striated

428 INFLAMMATION.

corpuscles are, as a rule, found after the involution of the organ.
Among the blood-vessels, the arteries of the spleen are often
seen in waxy degeneration before the other constituent parts
are attacked. (See Fig. 178.) The degeneration starts in the
smooth muscle-fibers of the middle coat; these are enlarged,
transformed into a homogeneous mass, in which no trace of
structure or of nuclei can be recognized. In the kidneys, the
waxy change is sometimes observed in the walls of the capillaries
sooner than in the arteries. In the liver, waxy degeneration
takes place independently of the blood-vessels.

Muscle-tissue is often subject to this degeneration, especially

U-

,.»>/ .3/

'J

■^,>^^.-- -\

Fig. 178. — Waxy Degexeratiox of an Artery of the Spleen of a
Man Affected with Syphilis.

E, endotheli.ll coat of artery : .V. mnscle-coat of artery, in waxy degeneration ; B, bandies
of smooth muscle-fibers accompanying the artery ; X», lyniph.corpuscle3 in the myxomatous
reticulum. Magnified 600 diameters.

the muscle of the heart, predominantly the wall of the left ven-
tricle, by which this structure is enlarged, rendered friable, and
of a peculiar lardaceous luster.

Waxy degeneration is often found in nerve-tissue, both in the
gray substance and the ganglionic elements, in connection with
similar changes in the walls of the blood-vessels, and also without

INFLAMMATION.

429

any such changes. For particulars I refer to the two foUowiuf^
articles. Epitlielia and endotlielia are likewise subject to this
defeneration — f. i., in the liv'cr, the kidneys. The ejiithelia of the
luuf^s sometimes give rise to homogeneous or concentrically stri-
ated colloid corpuscles, and such are sometimes observed in the
epitlielia of the prostate gland. The concentric colhjid corpus-
cles of the latter organ may become the seat of calcareous depo-
sitions, and are sometimes voided with the urine. They are not
of uncommon occurrence. (See chapter on urine.)

Peculiar, but certaiidy kindred, fonnations are the colloid
corpuscles of the nervous system. Usually they exhibit a concentric
striation ; sometimes two or more such concentrically striated
corpuscles may be surrounded by a common homogeneous or
striated layer. (See Fig. 179.) Virchow, by mistake, termed

^i^kM

>;aii

Fig. 179. — Colloid or Amylaceous Corpuscles op the Arachnoid
OF THE Spinal Cord of an Adult.

A, couceutrically striated amyloid corpuscle ; G, group of medullary corpuscles in colloid
degeneration ; L, medullary corpuscles lu tlie beginning of colloid degeneration. Magnified
600 diameters.

them ''amylaceous" corpuscles. In the arachnoid of a man
whose brain, crowded with these corpuscles, was in the condition
of the so-called *' gray atrophy," I could trace the origin of these
formations from meduUary elements, which had arisen in the
fibrous tissue of the arachnoid in consequence, evidently, of a

430 INFLAMMATION.

slight inflammatory process. The medullary corpuscles, being
infiltrated with the eoUoid material, either remained in irregular
groups, or, becoming elongated, gave rise to the concentricaUy
striated corpuscles, in a way similar to that in which the territo-
ries of connective tissue are formed. In the center, sometimes
an unchanged plastid is seen, or a larger homogeneous mass, or
a shallow depression, termed an umbilicus.

Waxy Degeneration of the Cerebellum. By J. Baxter Emerson.*

Mr. B. was the youngest of a family of seven childi-eu. His mother died of
acute eTicephalitis, terminating in abscess ; a maternal uncle and aunt both
showed symptoms of dementia late in Ufe. One of his sisters has suffered for
several years with hystei'ia ; a second sister has at the present time posterior
spinal sclerosis. When about fifteen years old, he was throAvn from a car-
riage, and received a severe scalp wound on the posterior part of his head,
from which he seemed to recover. His habits were regular. He was much
troubled with naso-pharyngeal catarrh. At the age of twenty-eight he lost all
his property, which worried him excessively; soon he foimd that he was
losing flesh and strength, that his appetite was poor and his digestion bad ; he
also had the tendency to fall when walking or on turning suddenly. His
brother noticed that he became slower in his work. In January, 1874, the
above sj-mptoms returned; he began to stammer, and would often forget
localities and names. These symptoms were intermittent in character ; at
times he was apparently well. In September, 1874, he was married, and,
while on his wedding trip, his wife noticed that if he endeavored to walk
down a flight of steps, he would become pale and complain of vertigo. Shortly
afterward he was attacked with most intense pain in the head, accompanied
with gi-eat irritability, photophobia, and inability to stand alone. These
acute symptoms lasted several days, and for several weeks he had to be led to
prevent his falling. About a month later he had a second similar attack, this
time losing the power of speech and being "delirious." Later, he complained
of "pain in the forehead," numbness of the extremities, occasional twitching
of the muscles, and he was unable to walk without assistance. On two occa-
sions he asserted that he was blind, which assertion he persisted in for two
days. He was exceetlingly childish in his actions. Toward the latter part of
the summer of 1S7G, he became violent, his hallucinations and delusions
being of an exalted character.

On October 5, 1S7G, I found his left pupil dilated, the tongue tremulous,
the power of eoortlinating the muscles much impaired, those of the left side
more so than the right ; the left biceps permanently contracted, so as to keep
the fore-arm at an angle of about one hundred and thirty-five degi'ees with the
axis of the arm; contractile power of the muscles on the right side more
marked than on the left ; an almost incessant movement of either the fore-arm
and hand, or gi-inding of the teeth; pai'tial anesthesia of the left side;
aphasia of both varieties, but principally amnesic ; hallucinations and delu-
sions of a very exalted character, seeming to dwell principally on financial

"Abstract of the paper '• Peri-euceplialitis," by J. Baxter Emerson, M. D., New-Y^ork.
Journal of Nervous and Mental Disease. Chicago, April, 1880.

IX FLA MM ATI OX. 431

subjects ; emotions not under control ; sense of decency lost ; using the most
obscene liuifiuiif^e ; resj)ondiiii; to calls of nature rej^ardless of surrounding
circumstances; dementia very marked, at times so violent as to necessitate
restraint ; insomnia.

On November 14, ISTC), lie Inul an attack, with the following symptoms:
Complete left hemiplegia antl hemiana'sthesia; complete aphasia ; congestion
of head and neck ; extremities cold, esjjecially the left ; head drawn to the
right, and lixed ; both eyeballs drawn to the right ; left pupil widely dilated ;
conscious, with sense of sight and hearing intact ; facial muscles slightly par-
alyzed on the right side; those of deglutition interfered with; respiration
irregular and sighing in character; pulse S4, irregular and intermittent;
tenijierature IOC. Soon after, the muscles of the paralyzed side began to
twitch, first in the extremities, gradually extending to the trunk, luitil,
finally, all the muscles of the left side were in a constant state of spasmodic
contraction. The next morning the symptoms were all gone, except slight
paralysis and aphasia, and the patient apparently better than before the
attack. These attacks, of varying intensity, occurred about once a month
during the remainder of the patient's life. Dementia became more marked.
He persisted in keeping up the movements of his right fore-arm and the
gi-inding of his teeth to the last ; consequently, their muscles retained the
normal size, while all others uiuierwent atrophy from disuse; but to the day
of his death he was able to walk with assistance. His urine was normal to
the last, but he had retention for five days previous to his death, which
occiu'red May 13, 1879, from exhaustion.

A post-mortem examination gave the following results : Body much ema-
ciated ; ulcer, the size of a dime, on sacrum. Dui-a mater much thickened
throughout its whole extent, adherent to the pia mater in spots, and firmly
adherent along sup. long, sinus and in the temporal regions, much more so on
the left side than on the right. The pia mater was much thickened and con-
gested, and had numerous ha?morrhages, from the size of a pin's head to that
of a split pea, imbedded in its structure. These were principally on the left
side, all confined to the upper surface. The pia mater was adherent to the
base of the skull and the brain, in spots. The brain was much congested,
weight -iO oz. The convolutions on the right side seemed deeper, and the
gray matter thicker than on the left. The white substance was slightly
darker than normal, and much congested. The consistency of the whole
normal, and all other parts negative.

A large portion of both hemispheres was removed and placed in Midler's
fluid, then in a weak solution of chromic acid, until it was sufficiently hard
for section, after which it was kept in dilute alcohol.

The pia mater was composed principally of bundles of decussating fibers
of connective tissue, coarser than normal, traversed by dilated and enlarged
blood-vessels, distended with blood, and around many of them were bundles
of spindles and inflammatory elements. This condition of connective tissue
is characteristic of an inflammatory process of chronic nature, which process
led to the formation of new connective tissue, while an acute reciirrence of
the same process has given rise to a new formation of inflammatory ele-
ments. The dura mater was found structiu"ally in the same condition as the
pia mater, but had no haemorrhages in it.

A vertical section thi-ough either hemisphere of the cerebellum with a low
power of the microscope gave the following appearance : The blood-vessels

432 INFLAMMATION.

could be traced from the pia mater, especially in the sulci V^etween the con-
volutions, through the external gray and granular layers into the white sub-
stance, profusely branching and ramifying, and almost invariably engorged
with blood. In numerous places there were ramifications closely resembling
those of the capillaries, with sharp, well-defined, fluting outlines, colorless,
and of a high refractive power. Such groups were found principally in the
granular layer, but extended somewhat into the contiguous layers. There
were also numerous isolated, highly refracting bodies, scattered throughout
the whole cerebellum, but mainly in the granular layer. With a higher power
of the microscope, peculiar changes of the capillaries were shown, first
described by C. Wedl — namely, the capillaries were transformed into either
single or double rows of brilliant, colorless globules, or completely trans-
formed into a glistening rod-like mass, with fluting outlines, and numerous,
partly pedunculated, buds. The large isolated bodies had all the character-
istics of the corpora amylacea — namely, they were concentrically striated
and umbilieated. In some instances, the umbilicus was found in direct union
with capillaries, which had undergone the above described changes. Excep-
tionally, I found the •' cells of Purkinje," ^^•ith their offshoots, presenting the
same glistening, highly refractive, appearance as the capillaries and corpora
amylacea. Some of the latter looked as if they were composed of a number
of shining globules, closely packed together, the outlines of the globules
being just traceable within the clusters.

I used the following re-agents : Carmine (Vjoth ammonia and alum solu-
tions), which stained the tissues, but left the globules colorless. Iodine (both
tincture and aqueous solution, both with and mthout sulphuric acid) ; the
result was unsatisfactory, for only once, after the use of the aqueous solution,
did I perceive any change in the globular bodies, and then the pale blue tint
was very indistinct, and only a few of the bodies affected. HwmatoxyJon pro-
duced a distinct violet upon the tissues and the blood-vessels, while the glob-
ules were little affected, if any, by it. Chloride of f/ohl (one-haLf per cent,
solution) made the outlines more distinct, but did not change the color of the
globules. Vioki methylaniline stained the granular layer a deep blue, the
external gray layers and the white substance a dirty gra\-ish-blue ; the
blood-vessels both in the normal and pathological condition were unaffected.
Fuchsine produced a pink stain in the gray layers ; the globular bodies and
blood-vessels were untouched. Osmic acid (one per cent, solution) pro-
duced a marked brown discoloration on the globules, but by no means as
deep as that we are accustomed to see on fat-globules. Picro-indi/jo gave
the blood-vessels and globules a bright green color, while the surrounding
tissues were of a much paler tint of green.

In unstained specimens, the refractive power of the globules and corpora
amylacea was so characteristic as to allow of no diagnosis, except calcareous
degeneration of capillaries, of corpora amylacea, and exceptionally of "cells
of Purkinje." In the whole list of my re-agents there was nothing found con-
tradictory to this, though, I must admit, very little to confirm it. The capil-
lary blood-vessels in several instances showed rows of calcareous globules on
both walls, while in the center a row of blood-corpuscles was still recognizable
in that portion of the capillary nearest the pia mater, while the central end of
the capillarj' was completely filled with the shining globules. The change,
therefore, which led to the formation of these globules must have taken place
in the walls of the capillaries, and in turn has led to the consolidation of the
entire blood-vessel.

INFLAMMATION. 433

Tho liifrhost powers of the mierosfopo ( IL'OO diameterH) showed in many
capillaries of the cerel)ellinn an enlargement of the endothelia, with a coarser
fji'aniilization therein, and a splittinj^ of the original endothelia into coarsely
granular clusters. The i)erivascular sheaths in some instances were consider-
ably dilated and sometimes tilled with globular elements, slightly increased
in refractive power. From the above facts it would seem that tho shining
globular bodies are products of the endothelia, which first become inflamed,
then proliferate, and the inflammatory elements thus formed become infil-
trated with lime-salts. Concerning the formation of the corpora amylaeea,
we at present know nothing. The gray layers of the cerebellum with a high
power of the microscope showed a reticular structure. The white substance
of the cei-ebellum was composed almost exclusively of nerve-fibers with
numerous varicosities, and a reticular struetiu'e was seen in the nerve-fiber
as well as in the varicosities. On broken ends of nerves, I could trace several
sheath-like layers, composed of a row of spindles, bounding the swollen pear-
shaped ends of the nerve-fiber, while the center of the so formed body showed
a delicate reticidar structure. Such formations, we know, never are seen so
long as myeline is present. It therefore follows that either the myeline has
oozed out after death, or has been absorbed during life, jierhaps in the same
manner that adipose tissue disappears in wasting diseases. The boundary
layer of the nerve-fiber in all instances was shining and homogeneous, thus
representing a complete sheath. There is no reason, therefore, to my mind,
for denying the existence of a sheath in the nerves of the white substance of
the cerebellum, and I may also add cerebrum, for they were both similar in
this case.

The gray substance of the cerebrum was similar iu structure to that of the
cerebellum. The calcareous corpora amylaeea were less frequently, and the
calcareous globules exceptionally, found. The blood-vessels were, as a rule,
distended with blood. The perivascular sheaths were, in some instances,
dilated. Several specimens showed a fatty degeneration of the blood-vessels
and of the ganglionic bodies, both demonstrated by their refraction and by
the action on them of osmic acid, which produced a black stain. The fat-
granules were arranged in the ganglionic bodies in a crescent shape, the con-
vexity being on one side of the ganglion, and the concavity toward the
nucleus. In the cerebrum I frequently found empty spaces, as they were
found also in the cerebellum — so-called vacuoles.* Most of the vacuoles had
in their interior a pale nucleiis, and their origin must be attributed to an
accumulation of fluid around the nucleus after death, or to a hydropic destruc-
tion of the ganglionic elements, due to serous exudation. The latter view is
corroborated by similar formations around the blood-vessels, where not only
lymph-sheaths were found dilated, containing bioplasson elements, but there
was also a large space around the IjTuph-sheath. Several ganglionic bodies
with partly fatty degeneration also showed closed empty spaces on the
periphery.

The diagnosis, as obtained from the microscope, in this case is chronic
pacluj-menin<jiti>i, meningitis, and encephalitis, terminatinfi in atrophy.

* I^ater oljservations in the gray substance of tlic brain and the spinal cord, which
were invaded l)y atrophy, due to clironic enceplialitis and nij-elitis, demonstrated that the
bioplasson reticulum was more or less rarified — viz. : its meshes enlarjjetl. There is a jsradual
transition of enlarged mesh-spaces to still larger spaces, termed vacuoles. I am unable to say
what becomes of the bioplasson in sucli a wasting process.— Kl>.

28

434 INFLAMMATION.

Waxy Degeneration of the Brain. By John A. Eockwell, M. D.*

The pathology of the central nervous system has as yet been very little
elucidated, for the simple reason that its minute anatomy has not as yet been
fully understood.

The reticulum In the gi'ay substance, first described by J. Gerlaeh, and by
L. Mauthner, twenty years ago, has been considered to be nervous in nature,
as both observers saw this reticulum in direct commimication with axis-cylin-
ders. Quite recently, however, tliis assertion has been contradicted by S.
Strieker and L. Unger, who claim that the reticulum is an elongation of the
pia mater, and therefore of connective-tissue nature. So far as my experience
goes, I must coincide with the views held by Gerlaeh and Mauthner. I invari-
ably succeeded in staining the reticulum of the gray substance violet with a
solution of chloride of gold, the same as the nuclei which are scattered
throughout the gray matter, and the ganglionic elements, whose nervous
natiu'e cannot be questioned. Moreover, I saw the reticulum in connection
with axis-cylinders, which we also know to be positively nervous elements.

It seems to me that the question. What is connective tissue, and what is
nervous structure in the gray substance I will never be definitely answered,
as the connective-tissue offshoots of the pia mater, upon reaching the finest
ramifications, lose their basis-substance and become bioplasson in nature, the
same as the nervous structure itself. C. Wedl was the first to maintain
that a waxy degeneration may invade the capillary blood-vessels, resulting in
the formation of shining, homogeneous cords, ramifying like blood-vessels
and freely supplied with pedunculated, bud-like, stratified projections.

The amylaceous corpuscles have, for a long time, been known to occur in
the gray substance of the central nervous system, where they represent bright,
stratified, apparently structureless masses, containing sometimes in their cen-
tral portion an unaltered plastid. Such corpuscles are so common, both in the
gi'ay substance of the brain and the spinal cord, and in the arachnoid of each,
that some histologists have asserted that they were normal formations. They
occur either singly or in double or multiple formations, clustered and partly
coalesced. Their designation, " amylaeeoiis," originated with Virchow, who,
upon applying iodine and dilute sulphuric acid, could in some instances pro-
duce a bluish tinge of these corpuscles. Upon the authority of Virchow the
name "amylaceous corpuscles" has been accepted, although the bluish color
after treatment with iodine — which feature reminded Virchow of starch cor-
puscles of plants — by later observers could not, or only in a very slight
degree, be produced. Evidently, the bluish color, wherever it occurs, is noth-
ing but the complementary color of these highly refracting bodies to the yel-
low-brown neighborhood after the apijlication of iodine. I consider this
re-agent of no value.

What the intimate nature of the amylaceous corpuscles, or the waxy
degeneration in general, is, we do not know. This much is certain, that the
formation of these corpuscles, as well as the waxy degeneration itself, is
closely connected with chemical alteration of the plasma of the blood, inas-
much as in almost all instances the waxy change is known to first invade the
blood-vessels. In the spleen and the kidneys the muscle-coat of the small

* Abstract of tlie i)aper, by Joliu A. Rockwell, "A Contribution to the Pathology of the
Brain." The New England Medical Gazette, Marcli, 1882.

INFLAMMATION. 435

artoriolos is, as a rule, tlie first to oxliibit the waxy chaiif^e. In the In-aiii,
the capillaries are unquestionably tlie first invadeil formations, as recently
proved attain by J. Baxter Emerson. The case frora which ray specimen has
come was one for two years under the observation of Dr. E. H. Linnell, of
Norwich, Conn.*

"Mr. T , aged sixty-three, of nervous temperament and thin habit, first

consulted me," says Dr. Linuell, "for failing vision, in November, 1879.
His vocation had been that of a photographer, until ill health obliged him
to relinquish it. Inquiry elicited the following facts : For the past eight
or nine years he had been subject to frequent attacks of neuralgia, affecting
his head and limbs ; he had been habitually constipated ; his urine had been
somewhat increased in quantity, light-colored, and passed frequently; and
for four years he had had paralysis agitans, affecting his right arm and leg, but
more nuirkedly the arm. This tremor developed gradually, and was attended
with partial ana3stjiesia, denoted by numbness and tingling sensations in the
affected limbs, and by general debility. In other respects he enjoyed good
health until the fall of 1S79. During the night of September 27th, of that
year, he had a sudden severe attack of pain in the head, extending from
vertex to chin, accompanied by total blindness, and followed by vertigo,
nausea, and slow pulse. After twenty-four hours the intensity of symptoms
was moderated, and his sight began very gradually to be restored, but was
never fully recovered. He continued to suffer with nem-algic headache and
vertigo, and his gait became halting and uncertain. His mental faculties,
however, remained unimpaired, and the paralysis agitans, or the difficulty of
locomotion, did not increase. When I first saw him, VOU = IB, refraction
Em. He had, however, left-sided binocular hemianopsia. ... In the latter
part of April, 1880, he had another sudden attack of complete blindness.
This attack was unattended by pain, and was of shorter dm-ation than the
first. During the following year his sight seemed to fail gradually, until he
could with difficulty distinguish large objects. He complained much of diz-
ziness, but suffered less pain ; walking became more fatiguing, the right leg
seeming heavy, and as if too long. He retained the use of all his faculties, and
could converse intelligently, although his mind seemed to lose some of its
natural vigor. In the latter part of June, 1881, he was suddenly seized with
a general tremor of the whole body, afterwards becoming more pronounced
upon the right side. This was not attended with pain, and he apparently
recovered from the effects of it ; but had a similar seiziu-e July 2, accompan-
ied with constriction of the post-cervical muscles. The rigidity increased, he
soon became unconscious, and was apparently entirely blind. After a few
hours he partly regained consciousness, and had perception of light. From
July 4 to 8, he seemed to improve somewhat. From this time he gi-adually
failed, both in intellect and strength, until he became comatose, in which con-
dition he remained for several days, and died July 19.

"Autopsy gave the following result : The dura mater was so firmly adher-
ent that the calvarium could not be removed without cutting; and in so
doing, several ounces of dark fluid blood escaped from the sinuses. Both the
dura mater and the arachnoid appeared healthy. The pia mater was much
injected, the veins being distended with dark blood. The entii-e weight of the
brain was two pounds, fifteen and one-half ounces. The cortical substance of
the cerebrum was of normal consistence ; but upon section of the right hemi-

* Published in the "Archives of Ophtlialmology," vol. x., No. 4, December, 1881.

436 INFLAMMATION.

sphere, a large and fiiin coagulum was found in the medullary substance. It
was nearly circular, and measured, approximately, foiu" centimeters in diam-
eter and two and one-half centimeters in thickness. It was situated a little
anterior to the center of the hemisphere, and did not anywhere encroach upon
the cortical substance. The contiguous brain substance was softened for
a thickness of about two lines, but the clot was removed almost entire, and
there was no serum, pus, or other indication of inflammation or of extensive
degeneration. No pathological changes could be discovered in the left hemi-
sphere. The fluid in the ventricles was not appreciably increased in amount,
although there was more serum upon the left than upon the right side. The
velum interpositum and choroid plexuses of the ventricles were highly vascu-
lar, the veins being turgid and swollen, and this was more marked upon the
left side. The tubercula quadragemina were manifestly degenerated, and
presented the appearance described as white softening. This condition was
much more evident upon the left side, but it was not limited to these bodies.
It also extended laterally and anteriorly, involving the corpora geniculata, the
posterior and inferior portions of the optic thalamus on the left side, and also,
to some extent, the floor of the fourth ventricle. A portion of the left optic
tract and the adjacent under surface of the thalamus was removed for micro-
scopical examination. This was so soft as to require very careful handling to
prevent crushing."

Dr. Linnell kindly sent me a portion of the under surface of the left optic
thalamus, which came to me preserved in alcohol. The specimen exhibited a
grajnsh-yellow discoloration, as if fatty. It was placed in a one-fifth per
cent, solution of chromic acid, and after a few days was sufficiently hard to
be sliced -with a razor. The sections were mounted in glycerine, and even
those which went thi'ough the treatment with alcohol and oil of cloves were
again introduced into water and mounted in dilute glycerine.

Incidentally, I wish to say that, for three years, I have been pursuing
microscopical studies in the laboratory of Dr. C. Heitzmanu, and by repeated
trials have become convinced that the moiuiting of specimens in glycerine is
far superior to mounting in Canada balsam or Damar varnish. Comparative
mountings in these liquids, especially for specimens of the nervous centers,
have resulted in the con%aetion that the balsam or varnish mounting ought to
be wholly abandoned. Unquestionably one, if not the main, reason why our
knowledge as to the pathology of the brain and the spinal cord has progressed
so slowly for the past twenty years is the mounting in balsam. By this method,
the specimens in a short time clear up to such an extent that the minutest details
fade, and the specimens become unfit for research with high amplifications of
the microscope (800 to 1200 diameters), which are the only jiossible means
of revealing the minutest normal, as well as pathological, features.

All the specimens obtained exhibited a peculiar change of the gray sub-
stance. This consisted in the presence of homogeneous, grayish fields of
greatly varying size and configuration, mostly with fluted outlines, scattered
throughout the gray substance. With lower powers of the microscope, I was
satisfied that these shining fields either accompanied capillary blood-vessels,
or were distributed without any regularity in the gray substance, or, lastly,
represented more or less straight tracts in closely lying parallel or in diverg-
ing fan-shaped courses, in the direction of the axis-cylinders. The latter feat-
ure was especially pronounced in the neighborhood of the optic tract. (See
Fig. 180.)

INFLAMMATION.

437

Tlu' shiiiint^ iieltis are doubtloHs in close relation to the capillary blood-
vesHels, inasmuch as thoy appeared, by the side of the capillaries, as if in the
perivascuhir space, without at first invading the endothelial coat itself. With
advancing degeneration in the neigliV)()rho()d of the blood-vessels, they also
became destroyed to such an extent that tlie direction of the glistening tracts
was the only indication of the course of the former cajjillaries ; though, also,
in such tracts, occasionally, a small portion of the original capillary was
found iml>edded. The numerous straight tracts following the course of the
axis-cylinders were e\ndently due to a degeneration upon a large scale.

Owing to the tolerably high degi-ee of refraction of these fields, my first
impression was that a fatty degeneration of the gray substance had taken
place. The treatment of the specimens, however, with strong alcohol and
oil of cloves at once revealed the fact that these formations could not be fat,
for they were not perceptibly altered by those re-agents. A second full proof
of their not being fat was the treatment with a one per cent, solution of
osmic acid, which we know
to be the most trustworthy
re-agent for fat, and which
should stain the fat black.
No such thing occurred in
my specimens.

The next question was,
could the waxy nature of
these fields be proved by the
application of different re- y
agents ? To answer this
question I applied the fol-
lowing re-agents : Carmine,
iodine, haematoxylon, fuch-
sine, violet methyl-aniline,
picro-indigo, and chloride of
gold. Among those, picro-
indigo was the only one
which, in Emerson's case,
yielded a positive result,
where the waxy blood-vessels
and globules were rendered
by it a bright gi-een. In my case
no one of these re-agents,
not even the picro-indigo,
yielded positive results, as
all the hyaline fields remained
unchanged in their color.

Nevertheless, I am satis-
fied that this change is ma-
terially a form of waxy de-
generation, somewhat different from the degeneration in Emerson's case, but
kindred to the waxy degeneration which J. B. Greene * described in the pla-
centa aa the most common cause of abortion and premature birth.

* " Aniericau Journal of Obstetrics aud Diseases of Women aud Cliildren," vol. xiii., No. 2,
April, 1880.

Fig. 180. — Waxy Degeneration of the Gray
Substance op the Thalamus Opticus.

V, capillarj' blood-vessel, coutaining a ^raiiularmass,
comiiressed at its upper portion, surrounded by a layer
of the waxy mass ; O, gray substance, the meshes of the
bioplasson enlarged by the waxy material, which col-
lects into brandling, irregularly contoured, shining
fields, in, Wi; N, nucleus of the graj' substance; a
part of the peiiphery, suiTouuded bj' a waxy mass.
Magnified 800 diameters.

438 INFLA MM A TION.

This certainty as to the nature of this degeneration could be obtained by a
study with high amplifications of the microscope, such as 1000 to 1200
diameters. The best specimens for the study with such high powers I obtained
by the treatment with a one-half per cent, solution of chloride of gold, in
which solution the specimens were placed for one hour and twenty minutes,
after having been thoroughly soaked in distilled water. By this, the blood-
vessels were rendered dark blue violet, and the gray substance, with its
nuclei, purple, while the shining fields remained unaffected. Here I could
see the fii-st change into the shining, homogeneous mass before mentioned, at
the periphery of the capillary blood-vessels, and in the mesh spaces of the
bioplassou reticulum. By the transformation of the licpiid contents of a mesh
spice into a semi-solid shining mass, the space became enlarged, and the
neighboring reticulum was pushed apart. By coalescence of neighboring
shining formations, larger clusters with fluting outlines originated, in the
middle of which often a faint trace of bioplassou was recognizable in the
shape of a few delicate gi-anules and their connecting filaments. Whether
or not the reticulimi of the bioplassou vsdthin the homogeneous masses was
destroyed, I am unable to say. Not quite infrequently I met with small
clusters of the homogeneous mass aroimd nuclei of the gray substance, as if
ensheathing them. In the further progi-ess of the degeneration, a gi-eat many
capillaries became destroyed ; probably first by pressui-e, and later by trans-
formation. These blood-vessels, fi-ee of the change just described, looked,
especially in their transverse sections, as if compressed and engorged with
blood-coi'puscles.

My researches prove that there are waxy degenerations going on in the
brain-tissue kindred to the waxy degeneration in other organs, such as the
spleen, the liver, the kidneys, and the placenta. The intimate reason of this
degeneration is not known, nor do we understand its intimate chemical con-
struction. One thing is certainly of interest in the case examined — namely,
that the blood-vessels being destroyed to great extent by waxy degeneration,
the cii'culation of the blood in the brain is interfered with, and an encephal-
itic process may in consequence ensue ; or the walls of the blood-vessels,
being rendered brittle by the waxy degeneration, may give way the same as
in fatty degeneration, and give rise to cerebral haemorrhage.

XII.

TUBERCULOSIS.*

MY \'iews on the subject of tulierculosis are based on exami-
nations of two hundred corpses in which tuberculosis
existed. In a number of these cases death had resulted from
other diseases, and tuberculosis was a secondary condition.t A
recapitulation of the literature of this subject is found in the
excellent book of L. Waldenl)urg'4

Nobody who, to-day, undertakes to discuss the question of the
formation of tubercle would be allowed to dweU only upon the
ilieonj of tubercle. On the contrary, he would be bound to con-
sider the former views, and to present the anatomical facts, in
order to demonstrate the admissibility of separating the tuber-
cidous granulation from tubercidous infiltration. This cannot be
accomplished simply by a description. Rokitansky has settled
the descriptive part in such a manner that scarcely anything is
left to be said. The views brought forward here are based
entirely upon my own observation ; they, to some extent, must be
eclectic and polemical. An answer to the question what the

* Translated from "Ueber Tuberkelbildimg." Wiener Med. Jahrbiieher,
1874.

1 1 was able to perform the post-mortem examinations in the dead-house of
the Wiedeu-hospital in Vienna, thanks to the kindness of the ciu-ator. Dr.
Quiquerez. After the publication of my essay, I made one hundi-ed more
examinations of tuberculous bodies, the sum total being, therefore, three
hundi-ed.

t"Die Tuberculose, die Lungenschwindsucht, und Scrofulose." Berlin,
1S69.

440 TUBERCULOSIS.

nature of tubercle really is can be given only after an accurate
examination of facts.

Tnhercnlosis of the Lungs. In order to properly group the dif-
ferent phenomena of tuberculosis of the lungs, it wiU be of
advantage to first illustrate its four principal varieties.

" Chronic tuberculosis " comj)rises a tolerably well-defined
group, which may be called' 'localized tuberculosis," as "chronic"
is an expression mostly clinical. This form appears most fre-
quently in the apices of the lungs, simultaneously in both,
although this is not without exceptions. As it is never fatal, jjer
se., we are rarely able to study it as a disease by itself. We meet
with it, as an intercurrent condition, in the bodies of individuals
dead of other diseases.

We find, imbedded in the lung-tissue, nodules of about the
size of a miUet- or hemp-seed, which have a gray or grayish-yel-
low color, are homogeneous, and of soft, or moderately firm, con-
sistency, or we see nodes, the size of a lentil or an almond,
distinctly marked from the surrounding tissue. These are cir-
cumscribed infiltrations, which, in transverse section, appear al-
most dry, homogeneous, and of a yellowish-red or yellowish-gray
color, which are in firm connection with the adjacent structures,
and not yielding juice or tissue-particles on being scraped with
the knife. Or, lastly, we find nodules or infiltrations of the size
before described, whose centers are usually soft and friable, which
can be mashed with the fingers, and from which the scraping-
knife can reduce crumbs and brittle particles. In the apices, in
some cases, nodules are the only formations present, and these
may be found either isolated or conglomerated into groups ; in
other cases we encounter only nodes, and therefore infiltrations.
Not infrequently we see in the same apex a varying number of
both nodules and nodes.

All subsequent changes of these formations relate chiefly
to the healing process; for, provided that no recurrences take
place, localized tuberculosis of the lungs, as a rule, terminates in
a cure.

The healing process may be accomplished in two ways. Either
it may start in the nodule or the infiltration while they are still
in connection with the lung structure, and they themselves rep-
resent a tissue, though a morbid one. Or the healing process
may start after the nodule or the infiltration have been trans-
formed into a brittle, friable mass, and therefore have ceased to
be a tissue.

TUBERCULOSIS. 441

In the first case, the tubercle is transformed into a semi-trans-
parent or white, consistent. ('artila<;e-lik(' mass (the fibrous tu])er-
cle of Virchow), which must be n-i^ardcd as dense caUous con-
nective tissue; ortlie nodule chanji^es into a firm, dark, ])i<;mented,
homog^encous, sometimes stratified, mass — that is, it becomes
horny or oljsolete. These hard nodules, attaining sometimes the
size of a siif;ar-i)ca, arc often found scattered in the lunfj^s.

If, on the contrary, the disintej^ration of the tissue has once
commenced, the crumbling mass becomes a foreign body, both as
regards the surrounding tissue and the whole organism. Here,
as aroimd every foreign body, inflammation sets in, and the
tissue around it is transformed into a firm connective-tissue cap-
sule, of varying diameter. The encysted product of tubercle
becomes a viscid, fatty, sometimes pigmented, paste ; or lime-
salts are deposited in it, which results in its being transformed
into a dry, cement-like mass. Finally, it becomes calcified, and
is termed a calcareous concretion.

The tissue in the neighborhood of the diseased focus behaves
differently, according to whether originally only discrete or con-
glomerated, and closely lying foci were present. The surround-
ings of a horny nodule are found to be lung-tissue, which is
radiatingly contracted, but otherwise normal, and from which
the hard mass can be easily dug out. The structures in the
neighborhood of a callous capsule, on the contrary, are fii-mly
concreted with it, so that the capsule cannot be separated from
the inclosing tissue.

If from the very beginning, in a circumscribed district of
lung-tissue, numerous nodules and infiltrations are present, and
the lung-tissue itself is in the condition of a chronic inflamma-
tion, the transformation into a hard, consistent callosity takes
place, more or less extensively, usually in the apices of the lungs.
The tissue is indurated, and, as it is almost constantly provided
with an abundant supply of dtu'k pigment, the callosity appears
of a slate-color, or even black. This is the pujmentari) induration
of Virchow, the cirrhosis of Corrigan and Buhl.

In the indurated lung-tissue are found all the before-men-
tioned methods by which tubercle is healed — viz. : the white,
almost cartilaginous, nodide, the size of a hemp-seed ; the gray
or black node of a concentric striation ; the cement-like or cal-
cified mass, directly imbedded in the callosity.

Observation, therefore, teaches that a genetic separation of the
tuberculous nodide from the tuberculous infiltration is not admis-

442 TUBERCULOSIS.

sible ; that the later metamorphoses depend materiallif upon the
circumstance whether or not the nodule or node remained a tissue ;
and, further, that the possi¥dit}j of a focus becoming callous depends
greatly upon its size ; and, lastly, that the solidification of the lung-
tissue may take place either by the formation of a capsule, or as a
diffuse induration, and any of these are secondary occurrences.

A second group, found most frequently in bodies of persons
who died of tuberculosis, is called subacute tuberculosis. As the
term " subacute '' is mostly a clinical expression, we might term
this from the disseminated or dispersed tuberculosis. Its charac-
teristic feature is, that new tuberculous nodules and infiltrations
are produced in comparatively short space of time, in consequence
of repeated reciu'rences.

If the ulcerative destruction has not reached a high degree,
we find almost constantly the first form of tuberculosis, as a
general thing, in the apices of the lungs. Upon examining an
apex, not too much destroyed, we notice that, while the horny
and calcareous nodules remain unchanged, the capsule originally
inclosing a friable product has undergone marked alterations.
In the transverse section of the callosity constituting the cap-
sule we find gray, grayish-yellow, or yellow nodules, the size of
a poppy- or hemp-seed ; the inner surface of the capsule is lined
with a fii'mly attached, grajdsh-yellow, layer, resembling croup-
ous formations. After the removal of this, the intensely red-
dened capsular wall is seen dotted with the before described
nodules. Many of these are in a process of softening, or disin-
tegration into a cheesy, friable mass.

When numerous nodules were originally formed in the cal-
losity, the inflammation accompanying the disintegration evi-
dently leads to suppuration, local mortification, and idceration
of the capsule. The bordering formation of new callous tissue
in the inflamed lung-tissue is scanty. Here and there a new
rudimentary capsule may appear ; or it altogether may be absent
where the disease is of rapid course, and then we find lung-
tissue, which is eroded, uneven, sinuous, and studded with granu-
lations. Consequently, we meet with transitions from an acute
inflammation of the capsule of a tubercidous focus to its sup-
puration, and to a partial new formation of a thin, so-called
pyogenous membrane, and, finally, to an ulcerative destruction
of the lung-tissue.

Simultaneously an exudation takes place into the canity, and
the crumbly contents are saturated with the liquid. Should sup-

TUBERCULOSIS. 443

puration ensue on the inner surface of the capsule, which is
frt'cly vasouhirized, the ])us niiuffles with the former contents, and
a thin, serous }>us results, which contains a nunil)er of frial)hi
particU's. This is the so-caHed fiihcrcKJoKs pus. At length the
entii'e mass becomes softened, and the formation of a cavity fol-
lows, which is inclosed by a capsule and is therefore a closed
abscess. Tlie caA'ity may be completely surrounded ])y lung-tis-
sue, thus producing the so-called parenchymatous cavity. If a
cavity arises from a bronchus by a formation of tubercles in its
mucous lining, or if perforation takes place into one or more
bronchi, a bronchial cavity is formed, which result must follow
after a certain size of the cavity is reached. By this means, the
expectoration of the contents becomes possible, and, also, the
access of atmospheric air to the contents of the cavity.

The walls between two or more cavities may be perforated by
ulcerations, due to a continuous or repeated formation of tuber-
cles. Lastly, a cavity may arise from the confluence of a number
of canities, of sizes varying from that of a walnut to that of the
fist of a child or the fist of a man, the walls being formed by
lung-tissue, which is partly callous, partly sinuous and corroded.

I would mention, incidentally, that not infrequently the cav-
ity is traversed by fii-m cords of different sizes, and the walls
thickly set with such formations. These are the remains of the
former blood-vessels of the lung, which, by thickening of their
adventitial coat, have become callous, and resisted the process
of ulceration. Sometimes, as is well known, a tuberculous nod-
ule, imbedded in the adventitia, may disintegrate before oblit-
eration of the vessel, and, in consequence of the ulcerative
destruction of the wall, a profuse or fatal haemorrhage may
ensue.

Finally, it may happen, perhaps, under the influence of
the penetrating air, that a rapid ulcerative destruction invades
large portions of the wall of the cavity, which becomes necrosed
and, together with the neighboring tissue, passes into gangrene.
Then we find the ca\'ity bordered by lung-tissue, of a grajash or
brownish-green color, eroded and containing irregular sinuses,
while its contents are an offensive, putrescent ichor, mixed with
blood, pus-flakes, and cheesy crumbs. These characteristics cor-
respond to the tuberculous phthisis of Laennec. This term may
be employed if we understand by it the ulcerative destruction
of the lung-tissue, and if, by the addition of " tuberculous," we
designate the nature of the destruction.

444 - TUBERCULOSIS.

In addition to the above-described changes taking place in
the neighborhood of the encysted or disintegrated foci, morbid
processes occur in the rest of the lung-tissue, most intense, as a
rule, in the upper lobes, while the lower lobes are comparatively
little affected. In more or less extensive districts, isolated nod-
ules, the size of a poppy- or millet- or hemp-seed, are observed ;
fii'st as gray, gelatinous dots in the lung-tissue, this being satur-
ated with a viscid, albuminous exudation. Starting from their
centers, the nodules then assume a grayish-yeUow color, after-
ward become yellow, and are finally transformed into a cheesy,
crumbly mass, before a capsule or callosity has formed in the
vicinity. While the old nodules take part in this metamorphosis,
fresh gray ones arise, so that we often find in the same lung
all transitions, from the gray to the yellow, and disintegrated
tuberculous nodule. Sometimes the nodules are grouped around
a bronchus in a wreath-like arrangement (Peribronchitis nodosa.
Buhl), or they may appear first at the periphery of a lobule which
is in the condition of a flabby, red, or grayish-red hepatization.
They may also fill the whole lobule, retaining their nodular form
as long as no disintegration has taken place.

Sometimes only scattered nodules are met with in the diseased
lung ; sometimes nodules are combined with infiltrations ; and
sometimes only infiltrations present themselves, which consist of
grayish-yellow, firm, half-dry foci, ranging in size from that of a
lentil to that of a hazel-nut, such as I have described as occurring
in chronic tuberculosis.

The infiltrations become disintegrated into a friable, crumbly
mass. This disintegration always starts from the centers of the
diseased parts. The view held by older pathologists, and also
by Virchow, is that the softening is a chemical process, occur-
ring, perhaps, independently of any imbibition of water from
without. This idea of a melting process taking place, as it were,
in the own liquid, follows from the belief that the infiltration
from its very outset appears of a certain size, and retains this
size until " melted " or transformed to " softened cheese." A
different explanation may be obtained if we remember the fact that
the node at its periphery continues enlarging, and that the oldest
focus of disease is to be looked for at the place where the soften-
ing starts. The tuberculous mass, therefore, may have become
soft by liquid derived from the inflamed neighboring parts before
peripheral new production has occurred, which still exists in the
^' cheesy " stage.

TUBERCULOSIS. 445

Softoned infiltrations are usually bounded by thin, yellow,
sinuous layers of tissue. In the vicinity the lunp: usually ap-
pears in the state of rtal)l)y, red hepatization, saturated with a
viscid exudate, and at other times it is moderately indurated.
The softening: of the infiltrations also terminates in the forma-
tion of cavities, and the ulcerative destruction of the lungs. This
variety of tuberculous phthisis differs from that (1escri})ed before
only in form and acuity, but not in any essential point, nor in
its terminations.

Sometinu's, scattered or clustered nodules and infiltrations
fill a district or the larger portion of a lobe so entirely that
this becomes rigid, fragile, and, in part, atelectatic. In such
cases, we may speak of a pneumonlform. suhacute iuherculosiSy
whose features are sufficiently marked to distinguish it from
catarrhal or " desquamative" pneumonia. If a group of nodules,
or an infiltration lying close to the pleura, is disintegrated, and
the pleura destroyed by ulceration, perforation into the pectoral
cavity may follow. This is the most common cause of pneumo-
and pyo -pneumothorax, which not infrequently accompany tuber-
culosis of the lungs.

In Jookiuf/ over the second form of fKherrnlosis of the lungs,,
we again are satisfied that there is no essential difference between
a nodule and an infiltration ; that either may be transformed into a
crumhlji mass and become softened. The next step — i. e., ulcera-
tion of the lung-tissue — is diff'erent only in its acuteness ; that is,
according to whether a number of scattered nodules are breaking
down at different times, or whether an infiltration is continnally
softened and simultaneously increases in size at its periphery. The
surrounding lung-tissue, in all forms of softening and local necrosis,
is evidently involved only in a secondary manner, therefore is in a
'' re-active," acute, or chronic infiammation.

The third form of tuberculosis of the lungs is comparatively
rare; it is called tuberculous pneumonia, pneumonia tuberculisans.
In the description of subacute tuberculosis, I have already men-
tioned that lobules, in flabby hepatization, are sometimes the
points where tuberculous nodules or infiltrations are formed.
Shoidd this grayish-red or gray hepatization involve a number
of lobides, or nearly the whole of a lobe, the features of lobular
pneumonia arise. It becomes tuberculous by the appearance of
gray and grayish-yellow nodules, or of gray and grajdsh-yeUow
infiltration, either in the neighborhood of bronchi or at the
periphery of the lobules, or scattered throughout them. In the

446 TUBEHCULOSIS.

initial stages of the disease the infiltrations are not sharply
marked from the surrounding hepatized lung-tissue. Sometimes
they have the appearance of being composed of numerous con-
glomerated particles the size of a pin's point.

At other times we find a lobe, or the larger portion of a
wing, in the condition of lohar pneumoma, consequently en-
larged, heav;y', dense, rigid, and without air — /. e., in a grayish-
red or gray hepatization ; and if the inflammation has invaded a
pigmented lung, it has the aspect of granite.

In genuine croupous pneimionia the section looks finely gran-
ular, owing to the filling of the alveoli ; if the inflammation has
attacked a coarsely spaced, atrophic lung, it is filled with coarser,
yellow exudation plugs. In tuberculous pneumonia, on the con-
trary, we find, usually, in the vicinity of the finer bronchi, groups
of moderately firm, grayish-yeUow nodules, in varying numbers,
imbedded in the hepatized tissue. I have observed this form
several times, generally in the lower lobes, after capital opera-
tions— f. i., amputations in individuals who, by previous sup-
purative processes, had become broken down.

In a third instance we find the whole wing in brown-red
hepatization, its tissue without air, firmly indurated with a slight
serous infiltration, and pervaded b}^ numerous nodules the size of
hemp-seed, or nodes from the sizes of a lentil to that of a hazel-
nut ; these are mostly softened. Such a hing exhibits an aspect
similar to that of porphyry. If the indurated tissue of the wing
is profusely pigmented, the pigmentary induration, therefore, has
invaded the whole wing, we find in it scattered nodules, usually
of a size not exceeding that of a millet- or hemp-seed, which may
be both obsolete and calcareous, or gray, grayish-yellow, and soft.
Here, too, the characteristics of pneumonia are marked and have
led to a condensation, hypertrophy, callosity, and pigmentary
induration. Still the nature of the process is sufficiently apparent
by the presence of the nodides and infiltrations.

Finally, we find in the indurated tissue of red-brown hepatiza-
tion of which only little is left, firm, grayish-yellow, half-dry
infiltrations, partly softened, about the size of a pea, hazel-nut, or
perhaps as large as a walnut, which are closely packed together
or confluent. An entire lobe, or wing, with the exception of
scanty remains of red-brown, hepatized lung-tissue, may be per-
vaded by this " cheesy" infiltration, which on being scraped
yields only a small amount of a cloudy liquid. Such an infiltra-
tion renders the diseased tissue friable and brittle. Only the

TUBERCULOSIS. 447

piirnicnt indicates the otherwise unrecognizable lung-tissue
(Kokitunsky).

One of the cases wliidi I observed deserves mentioning, because it will
be of value iu supporting the theory of tuberculosis, to be dwelt upon later.
A strong boy, a't. ir>, was taken to the hospital with the symptoms of tj-phoid
fever. Soon pneumonia of the right lung was diagnosticated. Two months
afterward the patient died, ^\ith sjnnptoms of a clinically diagnosticated tuber-
cidous pneumonia. In autopsy I found the right wing pervaded by " cheesy"
infiltrations to such a degree that the tissue was atelectatic and firm ; the left
lung at its apex contained an infiltration the size of a child's fist. The infiltra-
tions in both apices were softened, and in the right apex showed a number of
cavities of different sizes, but not very large. No traces of any previous
chronic tuberculosis could be discovered. The spleen, the small intestines, and
the mesenteric lymph-ganglia had the same appearance as seen iu t j^jihoid fever
after the healing process had been going on for a few weeks. Here, therefore,
under the influence of marasmus after typhoid fever, an original, clinically
well-marked genuine pneumonia was changed into a tuberculous pneumonia.

The nodules and infiltrations^ through their peculiarities, may he
at once recognised as tuberculous^ hpcause theg are marJiedh/ different
from analogous nodular infiltrations of the lungs, as observed in
carcinomatosis and pyeemia. The distinguishing features are: the
white color, the scanty vascularization, the wi-eath-like arrange-
ment around the pulmonary vessels in carcinomatosis ; the yellow
color, the softness, the partial disintegration to pus or ichor, the
purple color, and sometimes the dark red hepatization of the
neighboring parts in pya^mic infarctions.

A foiu'th form of tuberculosis of the lungs is known by the
name of the acute or miliary tuberculosis (Bayle). Here we find
both lungs diseased nearly simultaneously, and to nearly the same
extent. They are enlarged, heavy, profusely supplied with blood,
and sattu'ated with a viscid, cloudy exudate. In the apices we
encounter chronic and sometimes even healed tuberculosis ; in
other cases, no trace of this condition. The whole hj^eraemic
lung-tissue is pervaded in nearly uniform distribution by more or
less densely arranged gray, or grayish-yellow, soft, translucent,
opaque nodules, the size of poppy-, millet-, or hemp-seed. In
several cases, the largest and most numerous of these nodiUes
were found in the upper lobes ; comparatively few nodules of the
millet-seed size in the right middle lobe, and but ver}- fcAV gray
nodules the size of a poppy-seed (submiliary) in the lower lobes.
All cases of this variety exhibited in the meninges, the liver, the
spleen, the kidneys, and the peritoneum the same morbid condi-
tions in different combinations.

448 TUBEMCULOSIS.

Beyond this stage no changes are observed, for this form of the
disease, as' a rule, terminates fatally, with symptoms similar to
those of typhoid fever. This form is the rarest. It diifers from
nodular tuberculosis, termed subacute, only in the simultaneous
appearance of tubercle nodules in different organs and the acute-
ness of its course. I can corroborate, from my own careful
researches, the statement of Buhl that in ten per cent, of the
eases dead of this variety of tuberculosis no trace of cheesy focus
can be found.

Tuherrtdosis of the Serous and Mkcous Memhrnnps. Under this
head I shall only take into consideration tuberculosis of the
pleura and the peritoneum, as these have supplied me with the
most abimdaut material for observation.

In the pleui-a, we find tuberculosis is always combined with
the chronic or subacute form of the disease in the Imigs, and
in the peritoneum also, though here not so constantly, it is found
secondary to tuberculosis of other organs. This form of disease
has features corresponding with those of chronic tuberculosis of
the lungs, and may be considered as chronic tuberculosis of the
pleura and the peritoneum.

The pleura of one pectoral ca\dty, and the parietal peritoneum
in its whole extent, may be considerably thickened, and trans-
formed into a white, firm, and dense callosity. I have seen the
peritoneum in the pubic region as thick as the width of the little
finger. These callosities were either formed by the costal, dia-
phragmatic, and the pulmonary pleura, or, as is sometimes the
case, mostly by the costal pleura alone. In the abdominal cavity
the thickened parietal layer was concreted with the visceral layer
by means of thin, pseudo-merabraueous cords and plates. In the
callosity I found abundant foci, from the size of a hemp-seed to
that of a hazel-nut, containing a crumbly mass. In the pleura
I met even with cavities, ranging from the size of a hazel-nut to
that of a pigeon's-egg, which were filled with a mixture of pus
and cheesy particles. I could trace all transitions in consistence
and liquefaction, from cheese to pus. I have several times en-
countered such foci between the basis of the lung and the dia-
phragma, and also at the anterior border of the lung, with
perforations outward, between the third and the fourth rib. I
have also observed this condition at the posterior border of the
lung, in the niche formed by the union of the vertebrae and ribs,
with caries of single ribs. In the peritoneum I have observed
such cavities perforating into the abdominal space, with subse-

TUBERCULOSIS. 449

(jurnt ulceration of the ])S(>U(lo-inem))raneons adhesions, between
tlie ])arietal and visceral layer, and a final jx'rforation of the
intestine from without inwai'd.

Tlnit tnl)ereulous nodules of the ix'ritoueuni, however, may
heal up in the same way as those of the luufj^s is proved by cases
in which the small intestines are found massed together and
thickened, and at the per-iiihtny sun-ounded by a thick, pseudo-
memln-aneous capsule. Upon detacliinj^' the finnly a<i,glutinated
loops, the visceral peritoneum was found . strewn with nodules,
either isolated or in groups, of the size of a millet- or hemp-seed.
They were colorless, half translucent, and sometimes transparent,
having a vesicular appearance ; or they were white, firm, fibrous,
even cartilaginous, while many of the nodules and clusters were
surrounded l)y a narrow area of dark brown or gray pigment.

I have sometimes found, in the peritoneum, a second form of
tuberculosis, of a subacute character — /. ^., a miliary tubercu-
losis— with repeated recurrences. The conditions were the fol-
lowing: after opening the abdominal cavity, which was filled
with a serous or hemorrhagic exudation, I saw in both peritoneal
layers, besides firm nodules encircled by pigment, others which
were of a grayish-yellow or yellow color, surrounded by an
injected or ha^norrhagic area, and still other nodules which were
gray or gra;v'ish-yellow in color, tolerably soft, easily mashed, and
imbedded in the cloudy, swelled peritoneum. Scarcely a doubt
could arise that, in such cases, the '' fibrous " and pigmentary
nodides were the oldest, or they might even be healed, judging
from their analogy to the " obsolete " or " cartilaginous " nodules
of the lung, and also from the fact that pigment can form only
after a certain length of time. That, however, repeated recur-
rences had taken place was proved by the presence of tubercu-
lous nodules in their different stages, such as we have become
acquainted with through the researches of Laennec.

A third form is the acute, miUarij fahprculosis of the pleura
and the peritoneum., which is always combined with tuberculosis
of other organs. We find the pleura and the peritoneum thick-
ened by pseudo-membraneous layers and pervaded by innumera-
ble tubercles, which, in some parts, are isolated and in others
coalesced. Some of these are mere dots, the size of a pin's point,
and others are as large as a millet- or hemp-seed. All of them
show a nearly uniform grayish-yellow or yellow color. Pseudo-
membraneous callosities of varying thickness may be throughout
crowded with yellow tubercles, which have, to a gi-eat extent,
29

450 TUBERCULOSIS.

become confluent, and in some localities are packed together
without a trace of separating tissue. The same condition may be
observed in the omentum after it has gnjwn together into a firm,
bulky mass. Sometimes there are present simiiltaneously recent,
cobweb-like, freely vascularized pseudo-membranes, which may be
crowded with submiliary gray tubercle granules, not siu'passing
in size a pin's point.

Of the mucous membranes I shall consider only the mucosa of
the larynx, the intestine, the uterus, and its tubes. The differ-
ent forms of tubercle cannot be traced in mucous membranes,
because the nodules and infiltrations lie near the surface and
rapidly soften, disintegrate, and lead to ulcerative destruction
of the mucosa.

Doubts have been raised (Rheiner) whether or not the ulcers
in the posterior ivall of the larynx^ which are so often combined
with tuberculosis of the lungs, are really tuberculous in nature.
As is well known, they are either follicular or cleft-like, either
shallow and superficial, or sinuous ulcers, which, penetrating
into the depth, sometimes cause necrosis of the cartilages of the
larynx. All doubts regarding the tuberculous nature of these
ulcers will disappear if we see — though not in many instances, it
is true — in the mucosa of the lar\Tix, at the borders and the
basis of the ulcers, yellow, flat infiltrations, the size of millet-
or hemp-seed.

The mucosa of the lower ileum, the ccecum, the ascendimj and
transverse colon., offer a good chance to study, macroscopicaUy,
the genesis and the course of tuberculosis. Not infrequently we
see intestines in which there are all transitions, from minute,
follicular nodules and superficial ulcers, springing from them to
an ulceration, extending over several square inches in circum-
ference, the so-called tuberculous phthisis of the intestine.

The formation of tubercles, and the consequent ulceration, is
sometimes chronic and sometimes acute in its course (Roki-
tansky). I would mention here that the deepening and spreading
of the ulcers is due to a continuous new formation of tuberculous
nodules, which are seen as flat, grayish-yellow, and yeUow forma-
tions, the size of hemp-.seeds, imbedded in the inflamed tissue.
In the chronic course of tubercle formation a thickening of the
mucosa and of the sub-peritoneal tissue takes place, in the neigh-
borhood and at the base of the ulcer. The ileo-coecal valve may
remain as a ledge-like projection, of several lines in thickness,
of considerable density, and undermined by a number of sinu-
ous ulcers, empt\'ing above and below the valve.

TUBERCULOSIS. 4.11

When the ulceration penetrates the sub-peritoneal tissue, a
circuniscribed peritonitis always follows, corresponding in extent
to the size of the ulcer. This peritonitis is decidedly marked by
nodules, which are either discrete or groujjcd toji^ether in clus-
ters, of a yellow or grayish-yeDow color, and are imbedded in
the tissue of the peritoneum, which is swelled, opaque, and often
considei-a1)ly injected and ccehymosed. Such an acute localized
fornuition of tubercles, accompanied by considerable hj'pera^mia
of the peritoneum, may give rise either to a peritonitis confined
to the hypogastrium, or to a general purulent ])eritonitis. Fi-
nally, if in the peritoneum tubercle, in circumscribed places, is
softened and disintegrated, and if no protecting pseudo-membrane
has been pre\'iously formed, a perforation of the wall of the intes-
tine vdM take place, with an escape of the contents into the
al)dominal ca^'ity, and a general purulent peritonitis will set in,
with a rapidly fatal termination. Tuhercidosis of the mucosa of
the uterus and the tuhes exhibits similar ehai'acteristics. Here,
too, the primary tuberculous formation appears as flat, gi'ay. or
grayish-yellow granulations, which are only exceptionally found
in the mucosa of the fundus uteri and that of the swelled and
winding tubes. I encountered most frequently ulcerative destruc-
tion of the mucosa to a considerable extent. These id.cers were
shallow, and were defined by abrupt, sinuous, and irregularly
eroded borders. Upon remo\dng the cheesy, crumbly, and some-
times almost as if croupous, formation from the surface of the
mucosa, flat, gi-ayish-yellow infiltrations about the size of hemp-
seed became at once \'isible. Real nodides are of as rare an
occurrence in this situation as in the mucosa of the larynx ; for
the prominence, which is the essential feature of a nodule, is
wanting.

Tuberculosis and Scrofulosis of the Lymph-ganglia. O. Schiip-
pel* has an'ived at results widely different fi'om those of Virchow.
He admits the fact that there exists such a thing as primary
tuberculosis of the hmiph-ganglia, and that this may arise and
terminate as a pureh' local disease. He describes the tubercles
of the ganglia as '' globular, tolerably well-marked nodules of not
more than O. 3 mm. diameter, which are invariably and exclu-
sively located in the vascularized follicles of the ganglion."
Schiippel also considers only the nodules to be tubercles, and, in
his opinion, scrofulosis is nothing more than a miliary tuber-
culosis of the inflamed hyperplastic ganglion. This conception
I cannot accept as correct. True, sometimes we meet with
* " Untersuchungen iiber Lymphdriisen — Tubereulose," 1871.

452 TUBERCULOSIS.

nodules — /. r., promment fori nations of a size varying from that
of a pin's point to that of a hemp-seed — in ganglia which are
swelled, softened, and grayish-red. More commonly, however,
such nodules are wanting, and the diseased ganglion exhibits a
grayish-yellow discoloration, either throughcnit the transverse
section or only in a portion of it, and in the latter case the dis-
coloration is shai'ply marked from the gray-red, vascularized
portion of the ganglion. If a discoloration is observed in a sub-
miliary spot the size of a pin's prick or of a poppy-seed with-
out a protrusion, what reason have we for calling it a " nodule"?
Would it not be more correct to name such a condition an ''infil-
tration"? If we observe whitish-yellow submiliary spots on a
grayish-yellow basis, are we authorized in calling only the whitish-
yeUow parts tubercles? And, lastly, if the whole ganglion has
become homogeneous, grayish-yellow, half-dry and fria])le, where
are the tubercles?

I should say that here, as in every other tissue, a sharp dis-
tinction between the tuberculous nodule and the tuberculous infil-
tration leads to confusion and error, and I should prefer insisting
upon the genetic identity of both these forms, also in the lymph-
ganglia. I, however, agree with Schiippel in the view that the
tubercle is formed from an inflammatory new formation, and that
scrofulosis and tuberculosis are identical.

If we should place before a person a lymph-ganglion in
" cheesy" metamorphosis, without teUing him from what part of
the body it came and what were the concomitant phenomena,
would he be able to decide whether this ganglion was scrof-
ulous or tuberculous, or whether it came from the region of
typhoid or cancerous disease ? I should certainly think not. The
feature common to all is the grayish-yellow infiltration, the
" cheese '' of Virchow. Later stages of disintegration, softening,
suppuration, or calcification are also identical. Nevertheless,
Virchow considered it necessary to separate " scrofulosis " from
" tuberculosis."

To what the "cheesy" degeneration is due I will demonstrate
later. Here I only wish to maintain that there is no one in-
variable anatomical sign which would entitle us to call a given
ganglion either scrofulous or tuberculous. Schiippel, however,
deserves credit for having demonstrated, by the means of micro-
scopic research, that the theory of "hyperplasia" and ''hetero-
plasia" is not tenable, especially so far as tuberculosis of the
lymph-ganglia is concerned.

TUJiEL'CI'LOSfS. 453

Fiii.iUv. 1 would (li;i\v atU'iition to the fact that the ganglion
in gi-iiyisli-ycll(»\v or cliccsy infiltration may lu'conic softened
and siij>i)ui-att'. This process starts from certain centers, and
resnlts in the fornnition of a " scrofulous " abscess. In an abscess
of this kind, the thin pus mixed with cheesy crumbs is so charac-
teristic that the exi)erienced surgeon Sehuh at once made the
diagnosis of " scrof ulosis " in an apparently well-nourished indi-
viihial, when upon incision the abscess yielded pus of the above
description.

On the other hand, the softened infiltration may become
fatty and encysted, or calcified, and in the latter case the
whole lymph-ganglion in time is transformed to a calcareous
mass the size of a hazel-nut, such as we sometimes find in the
mesentery.

Tuberculosis of the Kidneys — Concomitant Xephrifis. Before
entering upon the description of my researches concerning tuber-
culosis of the kidneys, I would remark that the kidneys here con-
sidered were not primarily affected by tuberculosis, but the same
pathological condition existed in other organs, notably in the
lungs.

Not infrequently we meet, lioth in the pyramids and in the
cortical portion, with single, white, almost cartilaginous infiltra-
tions, of sizes varying from that of a millet- up to that of a hemp-
seed, w^hich are surrounded by unchanged kidney-tissue, and, in
accordance with analogous occurrences before described, might
be considered as healed tnhercles. Whether or not the fii'm, yel-
lowish-white, callous nodes, the size of a lentil or a pea, are tuber-
culous formations is doul)tful, for we also see such nodes in the
kidneys of non-tuberculous individuals. They might be, with
ecpial reason, considered healed infarctions, more particidarly if
any evidences of healed endocarditis are found.

Chronic and Suhacute Tnherculosis of the Kidneys I have
encountered much less fre(iuently than other forms of the
disease. I have occasionally seen small, yellow, friable infiltra-
tions in the swelled, cloudy, partly ecchymosed cortex, in the
neighborhood of which wreath-like or discrete infiltrations, the
size of a millet- or hemp-seed, were found. I concluded, fi-om
similar occurrences in the lungs, that the larger infiltrations were
the oldest, the smaller ones of a later date, without maintaining,
however, that the former originated from the latter. In chronic
tuberculosis of the kidneys, tuberculous phthisis may arise from
confluence of a number of foci, which, though a simultaneous cal-

454 TUBERCULOSIS.

lous condensation of the bordering connective tissue takes place,
may become softened and produce cavities (Rokitansky).

Lastly, acute miUurij tuherculosis of the kidneijs is observed as
infiltrations, not exceeding the size of a millet-seed, which, as a
rule, are most abundant in the cortical substance, and present, in
a comparatively small amount, in the pyi-amids. Such formations
are either scattered or, in part, clustered together, with simulta-
neous miliary tuberculosis of the lungs, the peritoneum, and the
liver. This form of tuberculosis of the kidneys I have seen but
twice.

Here I wish to draw attention to the nephritis which accom-
panies both the tuberculosis of the kidneys and that of other
organs. Usually, many different forms of nephritis are classed
under the head of '' Bright's disease," and Rokitansky especially
distinguishes an acute and a chronic form. I wish briefly to
state that, in these two varieties of Rokitansky, I recognize two
kinds of inflammation of the kidneys, readily distinguishable
as diseases sui generis. What Rokitansky describes as acute
"Bright's disease" should be designated croupous nephritis, a
characteristic of which, in addition to the inflammatory swelling
and redness or hypera?mia, is a diffused exudation. Rokitansky's
chronic form of '' Bright's disease," on the contrary, must be con-
sidered an interstitial, catarrhal, or desquamative nephritis.

In croupous nephritis tubular casts appear in the urine, and
large quantities of albumen, and the casts are recognizable even
after waxy degeneration of the kidneys has ensued. In catarrhal
nephritis, on the contrary, there is albumen in the urine in a
comparatively small quantity, the tubular casts are missing, and
only desquamated epithelia of the urinif erous tubules are found.
It is obvious that these forms of inflammation are different only
in degree and not in acuteness. Catarrhal nephritis may also
appear in an acute form and be followed by acute recurrences, in
which, as a rule, the urine becomes more albuminous.

The characteristic pathological sign of catarrhal or interstitial
nephritis is the striation of the sometimes slightly, sometimes
considerably, swelled cortical substance. The striation is most
marked on the boundary line between the cortical and pyramidal
substances. The seat of the disease is e\ddently the connective
tissue between the uriniferous tubules, while the exudation into
the tubules leads only to a desquamation of the epithelia, but not
to formations similar to those of croup of mucous membranes.
In acute catarrhal nephritis and in its acute recurrences there

TUBERCULOSIS. 455

are ^tiy striations, alternating with the dark brownisli-red
hypcru'inic kidney-tissue and the engorged blood-vessels. In the
eliroiiic form of this disease, on the contrary, the striation is of a
grayish-yeUow color, and there is no hypera3raia whatever of the
kidney-tissue.

One of the reasons which led to the statement that these
two varieties are different morl)id conditions, was the difference
observed in the appearance of the consecutive atrophj'. After
croupous nephritis this appears on the surface of the kidneys as
a coarse hdnilation, with the formation of irregular elevations
and dei)ressions of the cortical substance ; while after catarrhal
nephritis there is only a more or less uniform granulation and
shallow furrowing of the surface. The most striking proof is
furnished by kidneys which were in both poles in part attacked
by catarrhal and in part by croupous nephritis. The parts in
catarrhal inflammation exhibit fine granulation on the surface
and corresponding grayish-yellow striation of the nearly uni-
formly reduced cortical layer. lu the portion attacked by
croupous inflammation the surface is coarsely lobidar, and a
grayish-yellow infiltration prevails in both the irregularly
atrophied cortical and the reduced pyi-amidal layers.

In the highest degrees of atrophy after catarrhal nephritis
the kidney is uniformly reduced to a half, a third, or even less,
its original size, yet still there is an indication of the striation of
the narrowed cortex, which blends, almost -without a boundary
line, with the striated pyramids. The granulation of the surface is
very marked. After croupous nephritis in the highest degrees of
atrophy there are large nodes, separated from each other by deep
furrows, with an almost complete destruction of the cortical sub-
tance, and also a marked reduction of the pjo-amids, which are
pushed apart. In addition, there is a considerable amount of
fat at the periphery, and also at the hilus of the kidney, and a
more or less marked secondary waxy degeneration of the kidney-
tissue, which in some places may be reduced to a diameter of not
more than four to five lines.

In both forms of nephritis, however, fatty and ivaxy degenera-
tion occur. Fatty degeneration in either produces a diffuse yel-
low discoloration of the kidney, and for the recognition of the
original morbid process the increased volume of the organ and
the aspect of its surface are decisive. I have observed high
degree of waxy degeneration after both kinds of nephritis, but
so far as my subjects of observation admit of a conclusion, I

456 TUBERCULOSIS.

should say this condition was less frequent after catarrhal than
after croupous nephritis. In the first instance, the waxy
degeneration invades a pale or dark-brownish-red kidney, or it
may be confined to the pyramidal substance only ; while in the
last instance the lardaceous appearance is uniformly distributed
throughout the organ.

Out of two hundred eases of tuberculosis of different organs I found
croupous nephritis only seven times. In l)odies, on the contrary,
in which tuberculosis was the cause of death, I have never failed in
finding catarrhal nephritis. I am far from connecting nephritis
in causal relation with the tuberculosis of other organs. Catarrhal
nephritis almost invariably accompanies all severe acute and
chronic diseases — f. i., croupous pneumonia, typhoid fever,. small-
pox, pyaemia, chronic suppurative processes, etc. Besides, both
forms of nephritis may appear primarily with tlie well-known
symptoms, and in their severest forms lead to a fatal termination.

Theory of Tuberculosis.

Anatomical Signs of the Tubercle. We must examine the char-
acteristics of the morbid process which are concerned in the
formation of tubercle : the features which are observed by the
naked eye, those brought to light by the microscope, and those
inferred from the views taken by different pathologists. In this
way we may obtain a definition of the tubercle.

What are the characteristic features of tubercle ?

Is it the nodular shape ? Certainly not. We know of a num-
ber of diseases of the skin which are characterized by nodules,
such as lichen, milium, acne, etc., and aU follicular furuncles are
at first nodular. We know that in catarrhal inflamnuxtion of the
mucous membranes nodular follicular swellings occur, which dis-
appear as soon as the inflammation subsides. Occasionally we
find, in corpses where there is no sign of tuberculosis, nodules
the size of a pin's point or a poppy-seed, in the peritoneal cover-
ing of the hver and sj)leen, and sometimes, also, in^ the pleura.
These are very firm, transparent, without an injected area, and
are located on slightly cloudy or unchanged bases. Their origin
is apparent to any one who has seen acute pleuritis, especially
in the neighborhood of peripheral pyemic infarctions of the
lung, and acute peritonitis in its earliest stages — f. i., in puer-
peral process. Further, we often encounter, chiefly at the free

TUBERCULOSIS. 457

border of the bicuspid valve, nodules the size of a millet- or
heiiii>-seed ; these are sometiines ])ediiiieulated, and are papillary
vegH'tations from former endocarditis. Lastly, a numl)er of
tumors, fibroma, pa])illonia, sareoma, and cancer appear, first as
a nodule. Who would think of designating such nodules tuber-
cles, although they are in reality " tubereula''^ f

Is it the form of an infiltration ? We have no better grounds
for that. The swelled patches and solitary follicles of the mu-
cosa of the intestines, the enlarged bronchial and mesenteric
lymph-ganglia in typhoid fever, pyemic infarctions of the lungs,
etc., fm-nish examples of circumscribed infiltrations ; in croupous
pneumonia and in croupous nephritis we have specimens of dif-
fuse infiltrations, and such infiltrations, it is obvious, have noth-
ing in common with tuberculosis.

We, therefore, look in vain for the shape to distinctly charac-
terize the disease termed tuberculosis. Not only tuberculosis, but
any product of infidmmation, may appear at one time as a nodule,
at other times as an infiltration. Let us search further for a
pathological feature peculiar to this disease.

Is it the cheesy metamorphosis ? We know, on the one hand,
that tuljerculous nodules do not always pass on to this meta-
morphosis, as is demonstrated by the isolated ''fibrous "tubercles
of serous membranes, whose cure is made manifest by the pig-
mentary area and by the obsolete nodes of the lungs, which,
as mentioned before, sometimes attain the size of a sugar-pea.
We know, on the other hand, that the tissues of cancer, of ty]3hoid
lymph-ganglia, nay, pus itself, may undergo a cheesy metamor-
phosis. Virchow announced that a tissue might, under some con-
ditions, become caseous, as it might under other conditions enter
calcareous, fatty degeneration or become putrescent. According
to his view, there is a hyperplasia which terminates into a cas-
eous condition (scrofule of a lymph-ganglion) and a hetero-
plasia which also terminates in the same caseous change (tubercle,
cancer). This '^ cheesy" change, therefore, cannot be an essential
feature of tubercle.

Is it the heteroplasia ? In Virchow's classification the miliary
tubercles belong to the lymphatic tumors ; they are adenoid —
'/. e., gland-like new formations and heteroplastic productions —
which means that they originate " in places in which they do not
belong." I cannot think that Virchow intended this for a serious
definition. We know perfectly well that any inflammatory new
formation, without exception, any '* accumulation of cells," may

458 TUBEBCULOSIS.

be of a "lymphoid" character, — f. i., the granulations of a wound,

and very likely every disease does originate in a place where it

does not belong. Besides, Schiippel (I. c.) has demonstrated that
the view of a "heteroplastic" origin of the tubercles of the
lymph-ganglia is not tenable.

More i-ecently, efforts have been made to locate the essential
sio-n of the tubercle in its multinuclear elements — Rokitansky's
mother-cells. In this view, the presence of a central " multinu-
clear cell " would be sufficient to stigmatize all the surrounding
^'lymphoid" new formation as tuberculous. We know that the
so-called " giant-cells " occur, not only in normal medullary tissue
of bone and in inflamed tissues, such as cornea, cartilage, bone,
but also in a number of tumors (sarcomata), so that it is impossi-
ble to consider them as definite characteristics of the formation
of tubercle. They are no more specific for this disease than are
the " tubercle-cells " of Lebert.

Neither are we justified in claiming that the minute size of
the elements, their transient nature, their "low vitality," are
characteristic. The so-called " small-cellular" sarcomata and can-
cers in disintegration exhibit elements which are certainly still
less stable than those of the tubercle. Besides, we find in the
tubercle the large, so-called epitheloid, and also the very large
multinuclear elements.

This much is certain, that all previous definitions of tubercle
lack clearness. I again return to the question, what are the
essential characteristics of tubercle ?

Beyond doubt (and on this point all observers are agreed) the
tubercle is a new formation — i. e.j a new product "in a place
where it does not belong." It, however, has a peculiarity known
to aU accurate observers. It contains no blood-vessels. Tubercle,
therefore, is an avascular new formation.

Origin of Tubercle. As early as 1816 Broussais maintained
that the tubercle, or rather the "tuberculous matter,'' was a
product of inflammation. Much discussion followed this assertion,
\)\\t aU was to no purpose, since nobody then knew what inflam-
mation reaUy was. Most later observers have considered the
pneiimonic form of tuberculosis of the lungs as inflammatory in
nature, and even Virchow cannot be suspected, ha\ing considered
every tuberculosis due to inflammation.

While Broussais took "irritation" and "inflammation" for
one and the same process, Virchow, in a logical manner, sepa-
rated them. He says : " Primary tuberculosis of the lymph-glands

TUBERCULOSIS. 459

is primary only Jis tuberculosis, hut not as a process of irrita-
tion, wliose irritatin<; aj^eney is generally carried in from an
dtriiiDt" This inj2:cnious renuirk shows tluit the irritating a}^en(!y
is to l)e considered as the cause — the irritative process, on the
contrary, as the result. The ditference between the " ii'ritation "
of Broussais and the *' irritative process " of Virchow is obvious.

The liistory of the theory of inflammation elucidates tlic
meaninji: of the process under consideration. Humoral patholofj^y
placed it almost exclusively in the blood-vessels and in the diseased
blood. Cellular ]>atliolo^'v, on the contrary, set aside the ])lood-
vessels and everything- arising from the l>lood, and sought for the
essentials in a disease of the tissue, in the inflammatory new
formation. To the irritating agency at first the blood-vessels
only responded ; later, only the cells of the tissue.

S. Strieker, in 1S70, in opposition to these views, urged the
importance of the blood and the blood-vessels as factors in giving
rise to the inflammatory process; and he demonstrated that the
blood-vessels take an essential part in the production of tissue
changes.

Since then, somewhat more has been added. It is proved
through my own researches that, besides the exudation and the
new formation of living matter, the new formation of blood and
blood-vessels is an essential feature of traumatic inflammation.
I have shown that the process of inflammation first causes a
liberation of the living matter, which before was infiltrated
with basis-substance ; that the inflamed tissue first retiu*ns to
its juvenile or embryonal condition, and that it splits np in
the primordial elements from which it originated. The '^ inflam-
matory cell-infiltration," therefore, must be regarded only as the
representative of an early normal condition. A real '' inflamma-
tory new formation " does not take place till later, when the living
matter is newly formed and the elements divide in boundaries,
depending upon the more compact centers, the nucleoli and the
nuclei.

Rokitansky, in 1854, ascertained that the " tissue-cells" are
not by any means the only starting-points of inflammatory new
formation, but in the outgrowth of connective tissue the '' inter-
cellular substance" also participates actively. I demonstrated in
1873 that the basis-substance of all varieties of connective tissue
is abundantly supplied with living matter, and that after a dis-
solution or liquefaction of the glue-yielding basis-substance the
living matter is productive as well as the cells. I have therefore

460 TUBERCULOSIS.

supported the views held by Rokitansky, in opposition to the
plasma theory of Schwann and the cell-proliferation of Virchow.
The substratum of the inflammatory new formation, the out-
g-rowth of connective tissue, is the whole of the living matter of a
living tissue.

This process, as before mentioned, is constantly accompanied
by a new formation of red blood-corpuscles and also of blood-
vessels, due to a new formation of li\'ing matter. This occurs in
all tissues formed from the middle germinal layer, which from
their very origin are supplied with blood and blood-vessels.

The result of these processes is the formation of a new tissue,
which simHltaneoHsJij becomes vascularizHj, such as granulations,
vegetations, pseudo-membranes, etc. Vu-chow is satisfied in the
belief that a '' tissue " is a mere accumulation of " cells" ; whUe I
have proved that we are justified in applj-ing the term " tissue"
only when the elements are in a continuous lining connection.
Isolation of the elements produces pus; pus is not a tissue, and
not endowed with the capacity for forming a tissue.

The fact has been known a long time that inflammation may
exhibit marked differences, both in its course and in its termina-
tions. "Acute " and " chronic," " sthenic " and '* asthenic," "plas-
tic " and " suppurative " inflammation are expressions common to
all clinicians. One of the most striking differences in the course
of inflammation was based upon the circumstance that, in some
instances, the distui-bance is mainly confined to the vascular sys-
tem, in others it mainly appears in the inflamed tissue itself. One
of the main supports of the theory of the cellular pathology was
that the phenomena of vascular disturbance, nay, the blood-ves-
sels themselves, might be absent, — f. i., in the cornea or the car-
tilage,— and, notwithstanding, the tissue could become inflamed.
A new formation of '' cells," even suppuration, might occur in
siich tissues, these results being sufficient for the diagnosis of an
inflamed tissue. The essential featm-e of inflammation was the
new formation of " cells." To-day, things are different. With us,
a new formation of '' cells" means a new formation of living
matter, and we are satisfled that blood and blood-vessels are
requisite to set up an inflammation. We know, besides, that in
inflammation a number of blood-vessels perish, their hollow bio-
plasson becomes solid and is immediately appropriated for the
new formation of tissue; while a simultaneous formation of
blood-vessels is going on by the hollowing and vacuolation of
originally solid cords of living matter.

rrr.h'h'crLosTs. 4r,i

One fact only rcniciiiis to Ix; considered — namely, that on the
one hand the phenomena in the vascular system, under certain
circumstances, may be sli«jhtly marked, and on the other hand
the new formation of liviny matter nuiy ha comparatively so
scanty that in the infianied district a new formatiou of Wood-
vessels is completely absent. With this knowledge we may
undertake to analyze tubercle — it is immaterial whether in the
form of a nodule or an infiltration.

I'lihcrdc arises in vascKlarized tissues only. The inflammatory
phenonu'na in the vascular system in the initial stage of
forming nodules are not marked to the naked eye, but are rather
more distinct in the formation of an infiltration.

Tuberck'jfor the cellular pathologist, is a tissue composed of pro-
liferated and divided ''^ cells" ^ with us, it is hioplasson freed from
J)asls-snhstance, with a srauti/ new formation of living matter. This
explains the gray color and the softness of a fresh tubercle
nodule.

TuJjercle, furthermore, is a tissue which is connected with the
mother-tissue, and in which all elements are in a living union,
established by the connecting filaments.

Tuhercle is composed mostly of small elements, as there are
only small centers of living matter — viz.: small nuclei and
nucleoli.

Finally, tuhercle is avascular ; in other words, in the produc-
tion of the tissue of the tubercle the new formation of blood-ves-
sels is wanting.

Tuhercle may therefore he defined as an injiammatory new
formation:^ a tissue arising from an inflammation, with a scanty
new formation of living matter and without any new formation of
hlood-vessels.

Further Changes of Tuhercle. In our conception, all later meta-
morphoses of the tubercle become easily understood. So long as
tubercle is a tissue, in spite of the lack of blood-vessels, it may
give rise to new basis-substance ; and if it has not exceeded a
certain size, it then becomes fibrous or cartilaginous. This proc-
ess leads to a healing of tuhercle and to its obsolescence, while,
as the residuum remains an indurated nodule, a granulation (in
the sense of Bayle), a papillary vegetation. My views regarding
the curability of miliary tubercle fully coincide with those of
Empis and Waldenburg.

Far more frequently a shrinkage of the hioplasson, an absorp-
tion of the liquid, a so-called cheesy degeneration occurs, which is

462 TUBERCULOSIS.

due to the lack of blood-vessels, therefore to an insufficient sup-
ply of nourishing- material. In this condition the infiltration
may persist as a tissue for quite a time. It is only after the
shriveled, and in part fatty, elements are disconnected from the
mother-tissue, and from each other, that the crumbly and friable
mass becomes a foreign body, like pus. It then is subject either
to being encysted or to softening, to liquefaction from without,
and to necrosis. The first process is the result of an inflamma-
tion of the surrounding vascularized tissue, leading principally
to a new formation of callosities ; the second process is due to an
inflammation of the surrounding tissue, leading mainly to an
exudation and suppuration. In consequence of the suppuration
at the inner surface of the inflamed capsule serous pus arises,
mingled with crumbs, and a cavity filled with pus — an abscess
— is formed. The softened mass may become innocuous by a
process of fatty and calcareous metamorphosis, and, as such, will
not excite a new inflammation.

The '"'' caseous metamorphosis '' of Virchoiv, therefore., is due to
a shrinJcage, a desiccation of the new formation., tvhich is inflam-
matory in the tuhercle, in consequence of the absence of nourishing
hJood-vessels. The softening of the "■ cheese," on the contrary, as
has been already maintained by Lombard and Andral, is invari-
ably due to a hypergemia or ^inflammation of the vascularized
neighboring tissue, and to a stagnation in its blood-vessels, which
is frequentl}^ accompanied by haemorrhages and followed by the
formation of pigment. In this manner, the tubercle is removed
from the group of the lymphomatons new formations and the tuher-
cular 2)rodnct deprived of all specificitji.

Comparison with Suppuration. It only remains to draw the
parallels between tuberculization and suppuration, as these proc-
esses are evidently kindred to each other, Eeinhardt, who con-
sidered the tubercle as an inflammatory product, arising from an
exudate (1847), declared the yeUow tuberculous matter to be meta-
morphosed pus. This conception has nothing in common with
our ideas. That pus may become *' cheesy," in consequence
of an absorption of its liquid portions, and that pus-corpuscles
under these circumstances may be transformed into tubercle
corpuscles, — a process which Andi^al has termed tuberculization of
pus, — is unreservedly admitted. But this does not by any means
prove that suppuration and tuberculization are identical processes.
In suppuration there is also a stage in which the diseased tissue,

TUBKlU'l'LOSTS. 4G3

thouii-h iiifiltriitcd with i)us, is still u tissue. Tlic comparison with
pyii'inic iut'urctious of the luujj;-, as alluded to before, proves this
statement to be correct. The differences, however, are sharply
defined. Tlie firm, brittle, half-dry tubercidous infiltration ^rows
gradually, — /. e., in })eripheral recui-rences, therefore in a chronic
manner, — and may remain for months in the tissue stage before it
becomes softened and disintegrated. In suppuration, on the con-
trary, the whole process runs an acute course, being limited to a
few days. Eiglit days after an injury which was immediately
followed by purulent phlebitis, numerous suppurating pytemic
infarctions or abscesses may be found in the lungs, and the more
recent infarctions appear as soft, moist, yellow infiltrations. In
the production of pus within the inflammatory district, the new
formation of blood and blood-vessels is likewise absent, and the
living matter of older blood-vessels breaks down into the inflam-
matory new formation. Nevertheless, the result is strikingly
different from tuberculosis.

I recall the purple inflammatory area at the boundary and
the dark red hepatization in the vicinity of an infarction of the
lung, before alluded to. Such an inflammatory area is constantly
present around every acute abscess. The tissue in purulent infil-
tration is e\ddently richly supplied with liquid — i. e., an exuda-
tion from ^\ithout." When the separation of the elements follows,
they are suspended in a comparatively large amoiint of liquid,
the serum of pus. Then the result is the same as in the soft-
ening and suppuration in the formation of tubercle, namely, an
abscess, thougli in the latter instance this result only is reached
by slow process. The abscess in the former instance is '' acute,^^
contalnimi thick, genuine pus — the ^' good, laudable, and healthg
pus'" of the surgeons ; in the latter instance it is "chronic,'^ " scrof-
ulous,'' inclosing serous pus mingled with tuberculous matter. In
the former case the process is accomplished within a few days ; in
the latter it is extended over months and years. •

By inspissation of genuine pus and the shrinkage of the pus-
corpuscles the same condition will result as after incapsulation
of a softened tuberculous focus — viz.: a fatty, \dscid paste, a
cement-like mass, a calcareous concretion. Such a termination
of suppm-ation is well known, especially in peripsoitic abscesses.
If, on the contrary, an inundation of the inspissated pus takes
place by exudation from without, in consequence of new inflam-
mation, we find pus with " cheesy " crumbs, which is not materi-

464 TUBEBCULOSIS.

ally different from tuberculous jjus. The course and the
termination may be identical with that of an acute abscess after
the softened tubercle has become encysted.

Tuberculous and Scrofulous Diathesis. In conclusion, I wish
to make a few remarks on the scrofulous diathesis of the tissues.
This, according to Virchow, consists in a '' feeble resistance on
the part of tissues against disturbances, and a lowered capacity
for equalizing distm-bances ; in an increased vulnerability of the
parts, with a greater persistence of the disturbances." The latter
conditions are tlie consequence of a certain '' pathological consti-
tution," which consists in a " weakness of single parts or regions
and an especial weakness in their lymphatic organs," and we
must understand by this "a certain incompleteness in the arrange-
ment of the glands." Here we have the results of exact cellidar-
pathological research, and these results show what an important
advance the cellular theory of tissue diathesis involves, in com-
parison with the old humoral theory of the blood krases.

The swelling of the gland is originally of an ii-ritative, inflam-
matory, and hyperplastic nature ; but under the influence of a
certain " incompleteness in the arrangement of the glands," of a
certain "diathesis," it undergoes fiu'ther regressive metamor-
phoses, and among these the " cheesy " is the most common.
According to Virchow, the same holds good for the heteroplastic
new formation of tubercle proper.

In opposition to these assertions, it seems to be of advantage
not to abandon the gi'ound furnished T)y the above enumerated
facts.

Let us say : in the inflammatory new formation, which is the
substratum, not only of scrofulosis of the lymph-ganglia, but also
of tubercle, the old blood-vessels perish in the production of a
new tissue, and no new formation of blood-vessels takes place.
The succeeding step will be the shrinkage of the living matter,
under certain ciiCumstances the softening of the same, etc.

Let us say, further : certain organisms have not the capacity for
producing in a morbid condition, especially in the inflammatory
process, abundant living matter, and we have before us the
** scrofulous and tul)erculous diathesis." But we do not need
such a thing as a '' diathesis," for we only maintain what direct
observation proves. The scanty production of living matter first
causes a deficiency in the new formation of blood and blood-ves-
sels ; this influences the shrinkage of the inflammatoiy product ;
this in turn causes the disintegration, and finally the softening

TUBEIiCULOSIS. 465

by inflaniination of tlu' surrouiuliiif; tissiu', etc. Then tlu' cirdt*
is voiiiuled, and serufulosis and tnl)ercnl<)sis are identical,
according: to the ideas of Laennec and Rokitansky.

"Why, in certain or«i-anisnis, are the tissnes so easily inflamed?
Virchowsays: "It is reinarkal>le that the disi)osition for tuber-
culosis is always associated with a disposition for inflammation."
Here a«::ain a factor, the "dis])()sition" is introduced, which ouf^ht
to explain so much, and in reality does explain nothiny;.

Let us say: we do not know why inflammatory processes
occur, with much frequency, in certain organisms. Let us fur-
ther acknowledge that we do not know why inflammation ever
arises spontaneously ; in saying this, we speak the sim])le truth.

Then we are at liberty to analyze critically all experiments
which have been committed, since Villemin's time, for the pur-
pose of artificially x^roducing tul)ercul()sis in animals by inocula-
tion and infection ; but what would we gain ? It would be folly
to fight against observers — not to use a harsher expression —
who, even in our day, insist upon the infectiousness of cheese,
and assert that not every kind of cheese is eipially infectious. Wal-
denburg, one of the soundest experimenters, came to the conclu-
sion that tuberculosis, by which he, in agreement with Virchow,
obviously refers only to miliary tuberculosis, is due to the taking
into the circulation finely distributed corpuscular elements. These,
according to his view, would be deposited in numerous scattered
foci in various organs, with the formation of nodules. Inspis-
sated, cheesy pus, and caseous tissue of the lymph-ganglia, he
says, are most generally the subjects of absorption. With him,
too, miliar}^ tuberculosis is a disease of absorption, for he agrees
with the idea of Buhl, that miliary tuberculosis depends upon
preexisting cheesy foci — in the face of the fact that Buhl himself
admitted that in ten per cent, of the cases of miliary tuberculosis,
he was unable to discover any cheesy foci whatever.

What is the real gain from all this? Many experimenters
have succeeded in inducing an inflammation, every one in his own
way, perhaps through embolism, perhaps by a ditferent process.
All of them have produced '' miliary tubercles," — that is, circum-
scribed inflammatory products in circumscribed inflammatory
foci, — and it may be admitted that all this was brought about by
embolism. The inflammatory products, however, did not proceed
to vascularization, but shriveled up and became " cheesy," there-
fore tuberculous. This was not due to the skill of the experi-
menters, for the reason that the cause of such a result lay in the
' 30

466 TUBERCULOSIS.

organisms which were used for the experiment. That such a
metamorphosis is easily produced in rabbits and guinea-pigs is a
fact which has been well known for a long time.

I abstain from drawing conclusions concerning the therapy
of tubercle. For in the question of tubercle it is doubtless Vir-
chow's greatest merit that he has accurately defined the aims of
therapy, namely : " the removal of the disposition and the avoid-
ance of all obnoxious irritation."

To my assertions made in 1874 I have but little to add. Since
that time I have examined with the microscope a large number
of different organs affected with tuberculosis, and have no alter-
ation to make in my previous statements. More than this, I have
become acquainted with the anatomical features characteristic of
tuberculosis, recognizable not only in single pus-corpuscles, but,
from the peculiar aspect of the colorless blood-corpuscles, in every
fresh drop of blood. (See page 58.)

There is a want of living matter, and to this deficiency can be
traced all the features observed in scrofulous and tuberculous
individuals. This involves the peculiarity that such persons are
easily attacked by inflammation in general, and especially by
'* catarrhal " inflammation of the mucous membranes. This in-
cludes also an incapacity for reproducing blood-vessels destroyed
in the inflammatory new formation of medullary elements. Blood-
vessels being at first solid, bulky cords of bioplasson, which in a
latter stage are hollowed out, cannot be reproduced in certain
inflamed districts, and by this fact a clear understanding of the
puzzle termed tuberculosis is made evident to our minds. Dyscra-
sia, diathesis, disposition, and kindi'ed expressions, filling medical
literature and representing medical wisdom, deserve to be aban-
doned. For we have something positive, something that every
one can comprehend ; we have facts replacing all former vague
ideas expressed by a fanciful nomenclature.

Scrofulosis and tuherculosis are constitutional diseases. "Want
of living matter causes these and many kindred diseases, as,
f. i., caries of the bones, lupus, etc. Unfortunately, I have not
yet learned how to improve a person's constitution, how to increase
his living matter. Could we but do that, we might also extinguish
forever the misery produced by these constitutional diseases
which sweep away thousands of victims, (xenerations are sacri-
ficed to an irrational mode of living, to an irrational waste of
living matter, in excesses of all kinds.

TUBERCULOSIS. 467

As to more recent researches, I merely allude to the modern
\'iows, which decidedly favor the parasitic origin of tuberculosis.
This, it is said, is a coutajj^ious, an infectious disease, depending
on the presence of a certain inoc.idahle parasite. One claims
that a certain disposition is required for the reception of the
parasite ; another says that every one of us is tuberculous, only
in some there is no manifestation of the disease, etc. TuT)er-
culosis seems a regular witches' caldron for the brewing of
absurd theories.

A simple wound is sufficient to render a rabbit, a guinea-
pig, a dog, etc., tul)erculous, if these animals are kept in cellars,
in cages, and poorly fed. Even a lion will die of tuberculosis
under these circumstances. On the contrary, none of these
animals will ever become tuberculous if left in freedom, and
simply allowed to enjoy fresh air, proper food, and to live in a
climate suitable for their organizations.

XIII.

TIBIORS.*

DEFIXITIOX. Tumors are morbid outgrowths of li^'ing tis-
sues. An exact definition is impossible; and Vircliowt
himself has said: "If we were to torture a person to the last
degree of endurance, he would still be unable to tell what tumors
really are." The same author extends the limits of these forma-
tions to such a degree that he speaks of "tumors of extravasation
and of retention'' — that is, tumors which have ai'isen from a col-
lection of extravasated blood, or an exudate, or physiological
secretions. He furthermore dwells upon " granulation tumors,"
which, in the present view, are considered products of inflamma-
tion. We shall confine the idea of tumors to those formations
only which, by pathologists, are termed " neoplasma " or " pseudo-
plasma," which originate without marked inflammatory symp-
toms, and terminate without a typical end; while the inflammatory
process is completed by the production of a cicatiix. The best
definition is undoubtedly that of A. Liicke, who says : " A tumor
is a growth produced hy new formation of tissue, without a physio-
logical termination.^^

* This chapter aims to present the outlines of oncology only. Since the
establishment of my laboratory in New-York, over seven years ago, I have
been generously supplied with specimens of tumors by a large number of
physicians. I desire to return my thanks to them, and must specially mention
by name Dr. H. B. Sands, for his kindness in this and other respects in sup-
port of my laboratory.

t " Die krankhaften Geschwiilste." Berlin, 1863-67. The most exhaust-
ive treaty on tumors, but unfortunately not completed.

TUMORS. 409

Orifjin. All tumors ori<^inat(' from iiuliffcrent or moduUjirv
elements, in nearly the same manner as tiiat by wliieh physioloj^-
ical tissues are produced. No tissue can increase or pass into
another, except throuifh the intervening' stafje of medullary tis-
sue, and no tumor arises from a normal tissue without the latter
first passing through the same intervening stage. Virchow
maintained that the ucav formation of a tissue — the hyperplasia
— is either homologous (homaM)-plastic, Lohstein)or heterologous
(heteroplastic, Lobstein) ; the former meaning a new formation
of a tissue, identical or similar to the parent-tissue ; the latter a
tissue differing in type from the parent-tissue. This idea cannot
be carried out, as every new formation is at first heterologous —
i. e., medullaiy tissue.

The reason why a tissue sometimes produces a tumor is not
understood. This, at least in some instances, appears to be due
to a long continued irritation, or to an injury. But in many
instances no such cause can be traced ; neither are we able to
explain why the reaction following irritation is, in some individ-
uals, an acute or chronic inflammation only, and in others the
production of a tumor in addition.

Tumors are tissues which, so long as they are in connection
with the living organism, are li\ing themselves — i. e., pervaded
by a delicate reticulum of Hviug matter in the same manner as
physiological tissues. The type of a tumor is usually that of a
physiological tissue ; in other words, there is no tissue constitut-
ing a tumor which differs materially from the normal tissues. A
difference, however, in many instances, is estal)lished, for the
reason that the tissue of a tumor remains in an embryonal or
medullary condition, without passing on to a more fully devel-
oped type, — f. i., in myeloma, — or else the combination of the tis-
sues is different from that which we know to be a physiological
type — f. i., in cancer.

It is an easy matter to explain the cause of the formation of a tumor by
the terms ^^ (/encral (Uafhesi/^," or " (jeneral or local (lispo.sition." Is there any-
thing satisfactory in such an assumption ? Is it not more correct to honestly
admit that we do not know the real etiology of a tumor ?

An apparent progi-ess was made by Thiersch (180;")) and by Waldeyer
(1868), who claimed that the epithelia of cancer arise invariably fi-om genu-
ine preexisting epithelia, and that, therefore, cancer can originate only in tis-
sues which are offspring of the upper and under germinal layer, and in a
physiological condition are constructed of epithelia. These assertions in turn
have been disproved by both clinical and microscopical observation. A
tumor once formed may gradually involve its neighborhood and grow at the

470 TUMORS.

expense of the siuTounding tissue ; it then bears the name of a malignant
tumor. We do not know where this capacity for infecting is located. Malig-
nant tumors have the property of producing their own kind in internal organs,
mostly in the lungs and the liver, although often their origin was far from
these organs. The inference is that particles of the tumor are cai-ried as
emboli by the vascular system of these organs, and being fixed there, owing
to the narrow capillaries, increase and involve the tissue in which they are
lodged. Cohnheim and Maas * have attempted experimentally to prove the
presence of embolisms by transferring pieces, freshly cut from the periosteum
of a dog, into the jugular vein of the same animal. Between the tenth and
sixteenth day after the experiment they found the periosteal pieces embolized
in the lungs, and exhibiting all the features characteristic of a new formation
of bone-tissue. In animals which were killed after the twentieth day they
found the pieces of periosteum shriveled, and no trace of ossification or of a
neighboring inflammation. The above-named observers claim that their
experiments prove the possibility of proliferation of cancer emboli, and, as
they were not successful with scraps of periosteum, they concluded that indi-
viduals with generalized tumors lack the capacity of removing useless mate-
rial from the organism.

S. Strieker t analyzes these results, and gives the following siunmary : (a)
Question: Are emboli of tumors capable of growing into tumors ? (h) Experi-
ment : Emboli of periosteum have perished, (c) Conclusion : Emboli of
tumors, therefore, do not perish.

Repeated experiments have been made to infect dogs, by transferring
particles of freshly extii-pated malignant tumoi's of man, by inoculation, or by
injection into the vascular system. C. O. Weber and B. v. Langenbeck have
reported positive results. But as these results are so few in comparison with
the failures of many other experimenters, and, in addition to this, dogs are
known to be frequently subject to malignant growths, the conclusions derived
from such experiments must be received with caution.

Composition and Localization. In the composition of tumors
connective tissue always enters, this structure being the carrier
of blood-vessels. The character of the tumor depends greatly upon
the amount of connective tissue present, its stage of develop-
ment, and its combination with other varieties of tissue, such as
muscles, nerves, and epithelia. There is a class of tumors which
are composed entirely of connective tissue and its derivations,
and exhibit a simple type of construction ; by Virchow these are
termed simple histoid tumors. Another class shows combinations
of several tissues, imitating, to some extent, the structure of cer-
tain organs of the body, and Virchow proposes for their designa-
tion the name organoid tmnors. In a third variety of tumors
the structures of different organs are incompletely represented,
and such growths are called by Virchow teratoid tumors. Lastly,

* Virohow's Archiv. Bil. Ixx.

t " Vorlesungen uber allg. u. exper. Patliologie." Wien, 1878.

TUMORS. 471

several types of tumors may be combined into what Virchow
desififiiates tioiiors of ronihiiidfioii. Tumors may hr. localized, that
is, coiiliued to the production of a siujilc <irowth in tht; l)ody; or,
in other instances, several or a nundx'r of tumors may appear.
In tlie latter case, all tumors may be produced by the same tissue
system ; or an originally solitary tumor may become multii)le by
Avliat is called iiifcrfioii. Infection with the formation of niultijJe
tumors may ag'aiu be local if the tumors are near each other; or
general, if the multiplication is brought about by the infection
of different, usually internal, organs, distant from the oi-iginal
seat of the disease. In myeloma the infection is })rimarily car-
ried by the blood-vessels; in cancers almost always by the
lymphatic system.

BfHhjniifi atul nidi i(/n iff/. For a nunil)er of years tumors have
been divided, according to their clinical features, into heniyn and
mdl'mnant. This designation is based upon the nature of the
tumors, as well as their clinical course. Nobody doubts that a
tumor as such can never be altogether benign, as it always
expresses a morbid condition, and tumors of a so-called benign
character may produce distressing and even fatal results by pres-
sure and tension, atropy of organs, or disturbance of their func-
tion. But it is of great importance to preserve the clinical
nomenclature, so much the more from the fact that the patho-
logical and microscopical features fully agree with the clinical
observation.

Benign tumors are those which appear in most instances as
single growths; if multiple, they arise in the same tissue system;
for instance, many chondi-omata are found in the osseous sys-
tem, many lipomata in the sul)cutaneous tissue, many fibromata
in the skin. They remain local during their entire course, are
not infectious, and do harm only by disfigurement, ulceration,
pressure, and tension. Such tumors are either composed of
simple tissues or combinations imitating the structiu-e of the
normal organs.

Malignant tumors are those which, though appearing originally
as single tumors, subsequently, by local infection or by *' metas-
tasis,"— /. e.j transportation into other organs, — become multiple,
therefore they are also called infectious tumors. Sooner or later,
but invariably, they lead to general disturbances, to a breaking
down of the constitution, and to a fatal termination, either by
exhaustion, by hemorrhage, or by interference with the function
of important internal organs, such as lungs, liver, kidneys, etc.

472 TUMORS.

Uiihious tumors are those ■which at the outset exhibit a benign
type, but spontaneously, or by improper or incomplete surgical
interference, gradually assume the characteristics of malignant
tumors : or, being from the fii'st in a moderate degree mahgnant,
gradually become infectious, and multiply both locally and in the
internal organs.

The peculiar wasting of the body, the depreciation of the con-
stitution, the so-called " dyserasia," or '' cachexia," which by
former surgeons was considered as the primary cause of the for-
mation of malignant tumors, to-day is regarded as of secondarv^
origin. In former times, cancer was considered as the result
of a certain dyscrasia; to-day, surgeons are satisfied that tumors
of this kind are the results of a local or general disposition. These
expressions, as a matter of course, explain nothing.

faj Clinical and patholofjicdJ features. The clinical differences
between benign and malignant tumors are not distinctly marked in
all eases, but the degi*ee of malignity can usually be detei-mined.

Pain in benign tumors is only exceptional, and if present it is due to
pressure and tension, or a transient inflammation, and not lasting. Fibroma
and cavernous angioma are sometimes painful ; neuroma is, as a rule, painful
in a high degi-ee. Malignant tumors are from the first painful, or become
so in their course ; the more intense the pain the greater, as a general thing,
is their malignity. Especially painful are malignant tumors growing in locali-
ties which are abundantly supplied with nerves — f. i., the socket of the eye,
the parotid region, the tongue, etc.

The boundary in benign tiimors is, in most cases, sharply defined to the
sight or touch, and the tumor has a certain degree of movability, owing
frequently to the presence of an ensheathing capsule. Malignant tumors
usually appear as an infiltration, without sharp boundaries separating them
from the neighboring tissues. It is only exceptional that a malignant tumor
is sharply marked.

Grow til in benign tumors, as a rule, is decidedly slower than in malignant.
It takes a number of years for a fibroma to attain the size of a man's fist, while
malignant tumors often reach the same size in a few months or years.
Scirrhus or hard cancer is an exception ; it arises frequently with an apparent
diminution of the bulk of the organ invaded, — f. i., the female breast, — and
during a number of years shows only a Umited growth ; while, on the other
hand, some benign tumors (for instance, the so-called cysto-sarcoma or myxo-
adenoma of the female l>reast) may increase with great rapidity.

The integumoit in benign tumors remains movable and pliable even after
the tumor has reached considerable size. It is only after inflammation has
been induced by pressure that a fixation of the skin occurs. Malignant
tumors, though growing beneath the skin, very soon invade that structure and
render it immovable before any considerable distension has taken place. There
is an exception to this rule when an aponeurotic or serous layer intervenes
between the tumor and the skin.

TUMORS. 473

Tlio ininibcr. Benign tumors are often Hiiifjle; sometinieH, however, tliey
miiy ni)pear in larfje numbers, — f. i., fibroma, cliondroma, lipoma, papilloma, —
always jn'owinj^ from the same parent-tissue. Malignant tumors usually soon
multiply, either in their immediate neighborhood, or as a secondary process in
difTcn-nt localities, or in different systems and organs of the body. Excep-
tionally, very large and rai)idly gi'owing cancer and, as a rule, Hat cancer
(epithelionnv, rodent ulcer) of the face remain single.

I 'lv( ration. Benign tumors ulcerate only in consequence of local in-ita-
tion, by friction of clothing, pressure, their own weight, etc. Vascular
tumors (angionui) occasionally break open and idcerate spontaneously.
Malignant tumors (myeloma) often, cancer always, ulcerate, after having
attained a certain and usually limited size, if situated on the surface of the
body or in a cavity in direct connection with the surface. In organs of the
large cavities of the body a partial disintegration or softening of malignant
tumors may occur, as a process kindred to ulceration.

The idcerdfiuji siirfdce in benign tumors is smooth or covered with granula-
tions, and discharges ''healthy " pus ; the same feature is exhibited by the
ulcers of myeloma whenever such an ulceration occurs. Cancers, upon break-
ing open, present an iiTegularly deepened, often crateriforra ulcer, with a
rough, corroded base, lacking uniform granulation, and with jagged, abrupt
borders, discharging a scanty, ichorous pus. The tissues in the neighborhood
of a cancerous ulcer are invariably hard, almost cartilaginous, to the touch,
this being one of the most important diagnostic features.

After the formation of an ulcer benign tumors may swell slightly, without,
however, exhibiting any sign of more rapid growth, unless changing into a
malignant type. Malignant tumors, after ulceration, invariably gi-ow more
rapidly. The same is the case after poulticing, imtation with local remedies,
or injuries done through mistaken diagnosis with the trocar or lancet. The exu-
berant gi'owth of ulcerating malignant tumors takes the form of in-egular
vegetations, advancing toward the place of the least resistance, outward,
therefore in tumors of the surface of the body. Only flat cancer (rodent ulcer)
penetrates from the surface into the depth of the part affected without produc-
ing vegetations.

The hjnipltatic f/anf/lia in the ranf/e of beni(jn tumors swell only when they
are the seat of inflammation, in what is termed a consensual manner ; similar
swelling of the lymphatic ganglia may also occur in the earliest stages of
development of myeloma and cancer. After the removal of the tumor the
lymph-ganglia retm-n to their normal condition. A real infiltration of the
lymph-ganglion with its transformation into the tissue of the tumor, is excep-
tional in myeloma, but is the rule in cancer. Pain and fixation of the swelled
lymph-ganglion are the clinical signs of its invasion by the morbid growth.
This happens the more surely after ulceration has started in the original
tumor.

Recurrence after extirpation is exceptional with benign tumors, though
in some fibromata of the skin this occurs even after all diseased portions of
the neighboring tissue have been carefully removed. Local reappearance is the
rule with malignant tumors, with myeloma as well as cancer, and the recxu"-
rence usually takes i)lace within the first two years after extirpation. The
second tumor may appear either locally — i. e., in the cicatrix after the
operation — or in its neighborhood, indicating either that the "roots" of the
disease had been left behind, or thai? at the time of the operation the infection

474 TUMORS.

was present at some tlistant points not perceptible to clinical observation.
Every recurrent tumor, as a rule, takes on a more malignant type than the
preceding. EeciuTcnce in internal organs after extirpation is considered to
be due to the fact that the tissues were already affected vAXh. the disease at
the time of the operation.

A mi(Iti]>lication of benign tumors never occurs in internal organs, and what
was fonnerly considered a multiplication of chondroma, admits of a different
interpretation. A multiplicity of malignant tumors, both myeloma and
cancer, is often observed. Very probably this is due to a transportation of
tissue particles from the tumor, either directly into the vascular system (in
myeloma) or through the lymphatics and from them to the vascular system
(in cancer). These particles produce emboli in places where most numerous
and narrowest capillaries are found — /. e., in the lungs and the liver. A sat-
isfactory proof of the presence of such emboli has not as yet been obtained,
neither do we understand why the embolized particles should infect the neigh-
boring parts and transform the normal tissues into a fonnation like them-
selves. Such secondary tumors are sometimes present in enormous quantities,
exhibiting the structure of the primary tiimor. Not infrequently, however,
secondary tumors, after cancer, do not show a trace of the characteristic epi-
thelial structure of cancer, but that of myeloma.

fhj Histological Features. The examination of a tumor with
the microscope is of the utmost importance, as, in many instances,
it is only hy an examination of this kind that a correct diagnosis
of the nature of the tumor can be obtained.

In 1879 * I made the following statements :

'^ I fully concur with Prof. Llicke, of Strassburjr, in the opin-
ion that every practitioner should be acquainted with the minute
structure of tumors. Such knowledge would enable him to give
a more correct diagnosis and prognosis than is the case at
present. Very often we can decide the future of the patient
through microscopical examination of tumors, either after extir-
pation or before it, when small parts of the tumor are removed
for diagnostic purposes.

"We know that there exists a series of tumors — the benign
— which do not materially interfere with the health of the
patient. Such tumors are either formations of connective tissue,
with fully developed basis-substance in its four principal varie-
ties— viz.: myxomatous, fibrous, cartilaginous, or osseous; myx-
oma, fibroma, chondroma, and osteoma. Or they may be
composed of imitations of the fully developed tissues, sprung
from the middle germinal layer of the embryo, such as angioma,
lipoma, neuroma, myoma. Or, lastly, they may be combinations

* " The Aid which Medical Diagnosis receives from Recent Discoveries in
Microscopy." Archives of Medicine, vol. i., February, 1879.

TUMORS. 475

of epithelial and connective tissue, such as painlioiiia and ade-
noma.

''Another series of tumors, on the contrary, — called malig-
nant,— have a deleterious influence upon the constitution of the
patient. They grow rapidly, are ])ainfid, liable to ulceration,
recur very often after extirpation, and produce secondary tumors
in internal organs. For the differentiation of these growths we
are greatly indebted to R. Virchow. He first cleared up the fact
that some of these tumors are formations of connective tissue
in its undeveloi)ed embryonal or medullary condition, for which
he used the rather unsuitable denomination 'sarcoma'; while
others are combinations of epithelium and connective tissue —
the so-called cancer forms. A third variety of tumors exhibits
intermediate stages between these two kinds, and they represent
what is termed, in a popular expression, suspicious tumors, such
as myxo-, fibro-. chondro-, osteo-sarcoma, etc. These, upon theii-
first appearance, do not impair the constitution of the patient ;
but gradually, or after repeated extirpations, or rather trials of
exth'pation, become decidedly malignant.

" The study of the minute anatomy of tumors, in its present
condition, is as yet far from being satisfactory. Still, if the ques-
tion should be raised, whether microscopy has advanced so far
as to give a thorough decision of the benign, suspicious, or
malignant nature of a tumor, the answer, doubtless, will be a
hearty yes, it has.

" There are but very few points worthy of consideration as to
the natm-e of a tumor. The more of a hasis-suhsfance of the above
description is present., the smaller, therefore, the amount of free hio-
plasson bodies, the surer it is that the new grouih is of a benign
nature. On the contrary, the smaller the amount of basis-substance,
the larger the relative numher ofbioplasson bodies, the more cer-
tainlji does the tumor belong to a malignant type. The very worst
tumors — glio-sarcoma, round-cell- sarcoma, and medullary cancer
— exhibit a trifling amount of fibrous connective tissue. The
difference mentioned, namely, is true, not only for sarcoma, but
also for cancer. The more the connective tissue prevails, in
comparison with the epithelial formations, the less malignant is
its course, the more we are entitled to term it a ' scirrhus ' ;
while in the fast-gi'owing and rapidly killing medullary cancers,
the frame of connective tissue bearing the blood-vessels is very
small, and the epitheHa are ill-developed — viz. : remain in their
medullarv or embrvonal condition.

476 TUMOJRS.

*' Corabiuations of fully developed basis-substance, "with partial
retention of the embryonal character, are by no means rare ; they
involve what is termed the suspicious nature of the tumor. These
tumors allow of a prognosis of recurrence after extirpation, or of
a gradual change for the worse, when the surgeon, judging from
the appearances to the naked eye, has not the slightest idea of
the threatening danger. The inflammatory process in even
benign tumors may mislead the microscopist in exceptional
instances, and it is only by a thorough examination of different
parts of a tumor that a correct decision as to its nature can be
obtained. The presence of inflammatory elements within the
connective-tissue frame of cancer is well kno^vu to be decisive of
its malignant nature, and the circumstance that such elements
are often found on the surface of an extiipated cancer-tumor
indicates, on the one hand, that recurrence will rapidly ensue, on
the other hand, that such elements play an important part in the
new growth of epithelia, characteristic of cancer.''

Secondary Changes. The tissues of tumors are subject to the
same pathological changes which we observe in physiological
tissues. These changes sometimes deprive a malignant tumor of
its malignity, either in part or altogether, and they may occasion-
ally result in a spontaneous cure of either benign or malignant
tumors.

Inflammation ensues spontaneously, and after irritation or
mechanical injimes from T\-ithout. The inflammatory process is
different here in its results, though not in its aspect, from the
rapid new formation of tissue in malignant tumors. It some-
times leads to a formation of an abscess in the depth of the
tumor, and may terminate, as in physiological tissues, in the pro-
duction of a cicatrix. It sometimes causes ulceration — /. f,, a slow
necrosis of the superficial layers — or gangi'ene, \\'ith a partial or
complete destruction of the tumor. Gangrene may ensue from the
weight of a pedunculated tumor, from pressure, traction, etc.

Humor rhaf/e o(.'Curs most fi'equently in tumors which are
abundantly supplied with blood-vessels, or where the blood-ves-
sels are dilated. It may lead to the formation of encysted extra-
vasations in the middle of the tumor, — the so-called blood-cysts,
— from the waUs of which again a new growth of the tissue of
the tumor may arise. Ha-moiThage often causes pigmentation of
the tumors, Grangrene is sometimes produced after haemorrhage by
complete destruction of the tissue, and in this way a cure may
follow.

TUMORS. 477

Fxttji (Ji(/r)irni(i(>ii is often mot with, especially in malignant
tumors, and, if a larji:('r j)ortion be invaded, results in the forma-
tion of tile " reticulum " of older i)atholo<;ists. Fatty de<;enera-
tion rarely appears throufj^hout the entire tumor, but if this
happens, subsecjuent riilcijicdtlon and ossification ensue, reiulerinj^
the i^rowth harmless. Chcisij htctamorphosis is sometimes ol)-
served with the production of a yellow, friable, half-dry, shriveled
mass, as seen in tubercle ; this process is, as a rule, limited, and
has no influence upon the f urthei- growth of the tumor.

Mhcohs and colloid degeneration is a rather coinmon occiir-
rence, especially in adenoma and cancer, and results in the for-
mation of cijsts. Upon this metamorphosis rests the formation
of colloid and cystic cancer, and that of cysts in general. These
will l)e dwelt upon later. Waxy detjcneration is not infrequently
found. All these metamorphoses lessen in a great degree the
malignity of a tumor.

llijaJine or lujaJoid degeneration results in the transformation
of the tissue elements into a transparent mass, extremely indif-
ferent to the action of acids and alkalies, and is of rare occur-
rence; it invades the tumor partially only and has no influence
upon its general growth. The enlarged and concentrically stri-
ated elements of the tumor sometimes exhibit peculiar sprouts
and pedunculated formations — the ''gems" of Rokitansky and
the "physalids'' of Vil•cllow^ The intimate nature of these proc-
esses is far from l)eing understood.

Calcareous deposition is observed in fatty masses, transforming
them into a dry, brittle, cement-like substance ; or it produces an
incrustation of waxy or hyaloid corpuscles — for instance, in the
psanunoma ; or it invades all epithelia of cancer simiiltaneously,
rendering the tumor innocuous. Large masses of connective
tissue may become calcified, especially in fibrous tumors grown
from the periosteum. Ossification, with the production of more
or less irregular systems of lamellae, containing central medullary
spaces and well-defined bone-corpuscles, occurs in a limited num-
ber of tumors — fibroma, chondroma, myeloma, and so-called
osseous cancer. In most instances this process represents an only
incomplete mode of healing.

Classification. For over seven years I have taught in my
laboratory a systematic division of tumors — given in outlines in
my essay, published in 1879, above quoted. If we bear in mind
that an exact definition and classification is impossible — that
there are innumerable transitions of one kind of tumor into

478 TUMORS.

another, my mode of division will be found the simplest and most
satisfactory, so far as my experience, which is based upon the ex-
amination of many hundred tumors, permits a definite conclusion.
The system is strictly histological.

According to the four main varieties of basis-substance of
connective tissue — the myxomatous, fibrous, chondrogenous, and
osseous — I arrange the benign connective-tissue tumors proper
as follows :

1. Myxoma.

2. Fibroma.

3. Chondroma.

4. Osteoma.

The embryonal or medullary condition of the connective
tissue furnishes the well-known malignant type of :

5. Myeloma (sarcoma J.

The combination of connective tissue with fat, with a large
amount of blood-vessels, with muscles and nerves, provides four
other benign varieties :

6. Lipoma.

7. Angioma.

8. Myoma.

9. Weuroma.

Any one of the eight benign types may be combined with the
type of myeloma, and then they are termed : myxo-, fibro-, chon-
dro-, osteo-, lipo-, angio-, myo-, neuro-myeloma. This combination
shows that the tumor tends toward malignity.

The combination of connective with epithelial tissue results
in the production of two varieties of benign tumors, in which
the epithelium furnishes either the outer investment or produces
glandular formations :

10. Papilloma.

11. Adenoma.

The great majority of cysts are secondary formations of
adenoma, and may, therefore, be considered under the head of
adenoma. Adenoma may be constructed of myxomatous or
fibrous connective tissue : Myxo- and fibro-adenoma ; or it may
be built up by connective tissue in a medullary condition : Adeno-
myeloma.

The combination of connective tissue with epithelia not form-
ing glands, but either having the appearance of pegs, nests, or
plexuses, or filling alveoli, surrounded by connective tissue, gives
the malignant type of:

TUMORS. 470

12. Carcinoma.

This simple division and nonienclutuiv, as a matter of eonrse,
admits of many subdivisions and e.<mibinations. All secondary
changes, however, must be separated from the primary forms of
tumors, as enumerated in the above system,

1. Myxoma. Mucoid Tumor.

Myxoma or mucoid tumor is a soft, jelly-like, half -transpar-
ent gfrowth, either sessile or pedunculated, composed of myxoma-
tous connective tissue. Blood-vessels are somethnes abundant,
at other times the supply is scanty. Myxoma may combine with
other varieties of connective tissue ; frequently, also, it accom-
panies glandular new formation.

According to the different varieties of myxomatous tissue
(see page 147), myxoma appears in the following forms :

faj Myxoma of Reticular Structure. This is composed of a deli-
cate fibrous reticulum, holding chiefly at its points of intersection
nucleus-like oblong plastids. In the meshes of the net-work there
is a gelatinous, apparently homogeneous, basis-substance, which,
upon being stained with chloride of gold, exhibits a delicate
bioplasson reticulum. In the centers of the spaces lie single,
double, or multiple plastids, some of which are about the size of
a nucleus, while others show a finely granidar zone of bioplasson
around the nucleus. All plastids are connected by means of
delicate filaments with the bioplasson contained in the basis-
substance. (See Fig. 181.)

This variety of myxoma is sometimes scantily, sometimes
freely, supplied with blood-vessels. In the latter case the vessels,
though they have the character of capillai-ies, are very broad and
lined with large endothelia, and in their neighborhood the reticu-
lum is always narrower and richer in plastids than is the rest of
the tissue. It is this variety which is often combined with gland-
ular new formations of both the acinous and tubular varieties,
and then produces, if pediculated, the so-caUed polypoid tmuors
of the mucous membranes. (See article '' Adenoma.") Plastids
crowding the meshes of the reticulum are found either in rapidly
gi-owdng or in recurrent tumors, which are gradually assuming
the malignant type of myxo-myeloma.

Myxomata of reticular structirre are observed in the skin as
flat, sessile, or pediculated, smooth or raspberry-like tumors, or
they may be corrugated or lobate, and are often highly vascular-

480

TUMORS.

ized. In the latter case they bear the name myxo-angioma. If
the covering- epithelium is freely supplied with pigment, it estab-
lishes the variety called 7>/r/w*f»Ye(/ innvus ; such tumors maybe
congenital or they arise in middle life. Sometimes the myxo-
matous tissue in this situation is combined with fat, foiining
myxo-llpoma.

In mucous membranes myxoma is also common, usually as
pediculated, translucent tumors in the mucosa of the nasal, the
pharjTigeal cavity, the gums, the larynx, the rectum, and the
uterus. Often they are combined with glandular new formation,
representing the variety termed nujxo-adenoma. In the external
auditory canal and the tympanum they sometimes have the

Fig. 181. — Myxoma. Pharyngeal Polypus.

R, delicate fibrous reticulum with nuclei at the points of intersection, inclosing spaces
which cont.iin a jellj'-like basis-substance and plastids : P, eitlier nucleated or of the aspect of
nuclei ; V, blood-vessel. Magnified 600 diameters.

appearance of simple granulations, as observed in wounds heal-
ing by suppm-ation ; and as both granulations and myxomata
are identical in their minute structure, a positive statement as to
their etiology is impossible.

Myxoma also appears along nerves, and many of the tumors
termed '' neuromata" are myxomatous growths arising from the

TUMORS.

481

connective-tissue sheath of the nerve. Myxomatous tumors are
sometimes found in the parotid jjfland, in tlie female hreast, in the
ovaries and tlie testes. In tlie last-named positions they may be
combined with glandular and secondary cystic fcu-mations. Vir-
cliow observed myxoma in the medullary space of shaft-bones.
I have seen an iufm-ocidar nn/xoma completely filling the slightly
enlarged eyeball.

fhj Myxoma of the iStructurc of the Uml)ilical Cord. This is
composed of comparatively thick bioplasson strings which, hold-
ing a varying numbei- of nuclei, are united in a reticulum. The
meshes contain the jelly-like basis-substance, and in this are im-
bedded apparently isolated plastids, such as are found in the
tissue of the um])ilical cord. The homogeneous basis-substance
is sometimes mixed with fibrous connective tissue, either in .single

Fig. 182. — Myxoma of the Parotid Gland.

C, bioiilasson-cords, with numerous nuclei, branching and unitinj,' ; B, jellj-like hasis-
snbatance, which liolils single mostly central plastids, I. Magnified 600 diameters.

fibrillaB or in delicate bundles. Gold staining brings to \dew the
reticular bioplasson structure within both varieties of basis-sub-
stance, as it does in the tissue of the umbilical cord. (See Fig.
182.)

The myxoma of umbilical cord-structure is rarer than the
31

482

TUMORS.

reticular variety ; it is often combined with the latter or with
fibroma and chondroma. It has no blood-vessels ; but these are
found in the adjacent fibrous or reticular structure, never very-
abundantly.

(c) Myxoma of the Structure of the Thyroid Body, so called
Lymph-adenoma. We may class these growths among the myx-
omata, on account of the presence of lymph-corpuscles, filling
closed spaces or alveoli, which are surrounded by well-developed
fibrous connective tissue, carrying, as a rule, numerous blood-
vessels. These tumors are imitations of the structure of the
thyroid body, and are benign; while tumors which are con-

FiG. 183. — Myxoma or Lymph-adenoma, from the Upper
Jaw of a Woman.

C, frame of fibrous connective tissue, carrying blooil-vessels, J?,- i, lynipli-corpnscles fill-
ing tlie alveoli, some of wliicli are enn)tied by the cutting procedure. Magnifiecl 500
diameters.

structed on the plan of lymph-ganglia are decidedly malignant.
The latter I class among the myxo-myeloma.

Tumors of the lymphomatous kind have been termed lymph-
adenoma ; but as the word *' adenoma" means a glandular, there-
fore epithelial, structure, of which there is no trace either in
lymph-ganglia or in the more fully developed alveolar structure

TUMORS.

483

under consideration, the term lymphoma seems to l)e more ap-
jn'opriute, although this has heen previously disposed of for the
designation of the very malignant so-called " small cellular
sarcoma."

Tumors of the structure of the thyroid body are rare, and, so
far as I have been able to ascertain their clinical history, of a
thoroughly benign nature. Several of the cases which have come
under my observation occurred in the lateral region of the neck,
independently of the thyroid body. In one case, a tumor of this
kind, the size of a man's fist, occupied the region of })oth upper
jaws, having evidently started from the lining membrane of one
Antrum Highmori. (See Fig. 183.)

2. FiBROJiA. Fibrous Tumor.

Fibroma is a firm, dense, and opaque growth, either sessile or
pedunculated, composed entirely of bundles of a dense interlac-
ing fibrous connective tis- ^ ^
sue, which contains only a
fewblood-vessels. We may
cut the tumor at any point,
and wiU always meet with
bundles running in differ-
ent directions, which are
easily recognized with low
powers of the microscope.
(See Fig. 184.)

With high powers we
ascertain that the bun-
dles, hke those of physio-
logical dense fibrous con-
nective tissue, are com-
posed of delicate spindles,
closely packed together.
Between the spindles we
find finely granular bio-
plasson and plastids, mostly reduced to the size of nuclei. The
light interstices between the spindles are always traversed by
extremely dehcate transverse filaments, which interconnect the
bioplasson formations contained in the glue-yielding basis-sub-
stance. Similar filaments connect the bioplasson formations

Fig. 184. — Fibroma of the Vagina.

LL, buudlea of fibrous connective tissue, cut longi-
tudinally, interlacing with similar bundles at riffht
angles, D ; O, bundles cut obliquely, and F, bundles
cut transversely. Magnified 100 iliameters.

484

TUMOBS.

with the spindles. An oblique section of a bundle is obviously
marked by short spindles ; while the transverse section of the
bundle exhibits circular formations, which are surrounded by a
reticidum of bioplasson or of cement-substance. "Where capil-
lary blood-vessels traverse the tissue, the spindles are seen di-
rectly connected with the endothelial wall by means of delicate
filaments. (See Fig. 185.)

The varieties of fibroma are :

faj Loose fibrous connective tissue, composed of delicate bun-
dles of fibrillae (see page 159), builds up fibrous tumors of a

Fig. 1S5. — Fibroma of Vagina.

X, connective-tissne fibers composed of spindles, cut lon^tudinally ; O, oblique sections of
spindles ; T, transverse sections of spindles ; C, capillary blood-vessel. Magnified 1000
diameters.

moderate degree of consistency, while the vascular supply is
not abundant. They occur usually as sessile tumors of the skin,
with a smooth or lobulated surface, and, if pigmented, bear the
name of moles (naevus or melanoma). They are frequently found
on the mucous membranes, especially of the posterior nares, the
phar^-nx and larynx, and the uterus. Pol^^ous, pediculated tumors
of the uterus are often constructed of delicate fibrous connective
tissue, which in this situation is sometimes abundantly supplied
with blood-vessels. This variety blends -vs-ith the next.

fbj Mxjxo-fihroma or soft fibroma, which may be considered as
an intermediate stage between mj'xoma and fibroma. The m\^-

TUMORS.

485

omatoiis character is caused by the reticular arrangement of the
usually delicate bundles of connective-tissue fibers, which at the
same time inclose in their meshes a gelatinous, apparently homo-
geneous, myxomatous basis-substance, with single plastids, hav-
ing the appearance of nuclei. The fibrous character is produced
first by the circumstance that the reticulum is composed of a
number of fibrilhv, in the midst of which delicate rod-like or
spindle-shaped plastids are found, and secondly, by an inter-
lacing of dense bundles with bundles which are loose and deli-
cate. (See Fig. 1S6.)

Tumors of this kind often exhibit a transition from the
myxomatous to the fibrous structure; in addition to this they

Fig. 186. — M^-xo-fibkoma, Grown Beneath the Scapula

OF a WOILAN.

Bundles of fibrous connective tissue in a reticular arrangement. The spaces contain
either bundles, O, in an oblique or a transverse section, or a mucoid basis-substance, hoUUng
mostl3- central plastids, P. Magnilied 600 diameters.

sometimes abound in fat-globules, thus assuming the character
of lipoma. Myxo-fibroma is a common tumor in the skin and
the mucous membranes. Bulky, folded masses of the skin,
occurring in the face, on the chest, and the posterior aspect of
the body, the so-called leontiasis, belong to this class. It is of
somewhat rarer occurrence in the female breast, in internal
organs, and as a periosteal gi'owth.

486 TUMOBS.

fcj Dense, interlacing hnidles of filers (see page 162) are
found in firm, almost cartilagiuous tumors of the skin ; if
pediculated, they are termed fibroma moUuscum. They develop
in middle and advanced age, sometimes in large numbers all over
the skin, and some of them may reach a considerable size — viz.,
that of a man's fist, or even that of a man's head. Tumors of
this variety may be painful, like neuroma. In some individuals,
especially of the colored races, there exists a peculiar liability to
the formation of fibrous tiunors. Around the auricles of the
ear, in. females, they are usually caused by the piercing for ear-
rings. Such tumors are also remarkable for their disposition to
recur after extirpation, though, as a rule, the recurrent tumors
grow slowly, and retain their benign character.

(dj Scar-shaped fibroma, Jceloid is a flat, radiating, freely vas-
cularized fibroma of the skin, usually painful. It gi-ows slowly,
and attracts the neighboring skin in folds. It may gi-ow from
a scar, produced by previous operations with the knife, or by
caustics, or independently of any previous cicatrix. It is also
characterized by an extreme proneness to recuiTcnce. Accord-
ing to J. C. WaiTen, the cheloid is composed of more regular
bundles of fibrous connective tissue than the original scar.

Combinations. Fibrous connective tissue, combined with smooth
muscle-tissue, is of common occurrence in the uterus and its
appendages. Sometimes smooth muscles are so abundantly pre-
vailing in the composition of the timior that it deserves the
name of fihro-myoma, or myo-fihroma. These tumors will be con-
sidered in connection with myoma. Fibrous tumors, gi-owing
from the mucosa of the neck or the body of the uterus, may
sometimes also exhibit an enormous new formation of tubular
glands; a tumor of this construction must be considered as
adenoma. Fibrous tumors of both the uterus and the ovaries
not infrequently are supplied with a large number of blood-
vessels, and then may be styled fibro-angioma. Sometimes fibrous
tumors are the seat of partial depositions of lime-salts, — calcified
fibroma, — and, especially those grown from the periosteum, may
be partly transformed into bone — osteofibroma.

3. Chondroiha. Caetilaginous Tumor.

Chondroma is a dense, firm tumor, composed of cai-tilage,
either hyaline, fibrous, or reticular, or these varieties mixed.
The fibrous portions sometimes produce trabeculae, which carry

TUMORS. 487

the blood-vessels and inclose portions of the hyaline cartilage
structure.

Cartilaginous tumors are comparatively rare. They grow
both from the soft tissues and from bone, and are more common
in the latter situation than in the former. There are many
transitions from myxomatous and fibrous into cartilaginous con-
nective tissue, and the diagnosis often rests only on the large size
and the regular arrangement of the plastids, termed cartilage
coi-puscles.

Chondroma is a benign tumor which may appear multiple in the same kind
of tissue, but, as a rule, it does not infect the neighboring parts. In very-
exceptional cases, however, true chondroma attains the capacity not only to
infect its neighborhood, but also to produce secondary tumors in the Ivmgs,
never surpassing, however, the size of a walnut. Virchow enumerates six
cases of this kind.

Pathologists have described under the head of •' chondroma " soft tumors,
rich in "cells," which were imbedded in a scanty, gelatinous basis-substance.
Tumors of this kind were termed rillous chondroma and viucous chondroma;
tliey may gi-ow into the blood-vessels and prodiiee embolic metastases.
Obviously, tumors of this description, though resembling chondroma under
the microscope, are not cartilaginous tumors, but either myxo-myeloma or
chondi'o-myeloma, both beiug of a malignant type. If firm, genuine cartilag-
inous tumors are found in different localities of the body and in the Ivmgs,
also, there is no necessity for concluding that the latter are secondary
formations. For the lungs hold in the walls of the bronchi enough hyaline
cartilage to give rise under certain conditions (the chondromatous dyscrasia
or diathesis of some writers) to primary cartilaginous tumors.

Chondroma of the ''hyaline" variety is constructed like
physiological " hyaline " cartilage, the difference, at least in many
cases, being that in chondroma the plastids are of large size,
vary greatly in shapes, and are irregularly distributed. Besides,
the elements of chondroma are more coarsely granular — i. e.,
contain more hving matter than is found in normal cartilage.
The gold stain reveals the reticulum in the basis-substance, just
as in normal cartilage. (See Fig. 187.)

Cartilaginous new formation is found either throughout the
whole tumor, or in combinations with myxomatous, fibrous, or
bone-tissue; and sometimes, also, with myeloma, myoma, and
cancer. The latter combinations represent Virchow's group of
teratoid tumors — i. e., undeveloped remnants of all varieties of
tissues in one timior. This condition is probably due to an un-
developed organism, being inclosed in a fully developed one —
fcEtus in foetu. Formations of this kind are met with mostly in
the so-called dermoid cysts of the ovaries and the testes, although

488

TUMORS.

they have been found in other organs. I am indebted to Dr.
Clinton Wagner for a specimen of an almost perfectly developed
auricle of an ear, attached to the soft palate. Cartilaginous
tumors grown in glandular organs not infrequently exhibit
partial mucoid degeneration and secondary formation of cysts —
cysto-chondroma. Sometimes there is a calcareous deposition in

the tissue of chondroma and
^"■."#^^-1 S^^N a combination of cartilagin-
ous with bony tissue — osfeo-
chondroma ; or, as mention-
ed before, a combination of
chondroma vdth. myeloma
— cliondro - niijeloma. This
was the condition of a tum-
or the size of a child's skull,
grown in the testis, and
from which Fig. 187 is
taken.

Among the soft tissues,
chondroma is known to
occiu" primarily in the par-
otid and the submaxillary
gland, in the female breast,
in the periosteum of the
phalanges, in the testes, and
in the lungs. It causes only
local disturbances ; occa-
sionally, however, by sup-
puration and ulcerative destruction it may become rather seiious.
In hones, ehondi'oma originates either from the surface (perios-
teum) or from the cancellous portion, the diploe of skull-bones
and the central medullary space of shaft-bones. The most com-
mon places for chondroma to appear are the phalanges and meta-
cai-pal bones of the fingers, more rarely those of the toes ; next,
the epiphyses of the shaft-bones, the carpal and tarsal bones, the
ribs, the sternum, and very rarely the pelvis and skuU-bones, the
upper maxiUary bone, and the socket of the eye. The simulta-
neous growth of a number of cartilaginous tumors in several of
the above enumerated localities has also been observed. What
pathologists describe as central chondroma, arising from the
medulla of the shaft-bones, in many instances probably was,
judging from the clinical phenomena and the multiplication in
the lungs, myxo- and chondi-o-myeloma, but not pui-e chondroma.

Fig.

187. — Chondroma of Testicle.

P, plastids, mostly nucleated and coarsely gran
lUar ; B, finely granular, so-called " hyaline" basis
substance. Magnified 600 diameters.

TUMORS.

489

4. Osteoma. Osseous Tumor.

Osteoma is a solid tumor, composed of bone-tissue, and grow-
ings without symptoms of inflammation, in contradistinction to
the exostosis or the osteophytes, which are products of osteitis
and periostitis. Corresponding to the two principal varieties of
bone-tissue (see page 223), we have two kinds of osteoma :

(a) Cancellous or Epiphyseal or Spongy Osteoma. This occurs
on the epiphyseal ends of shaft-bones, closely connected with the
cancellous portion; it is found only in youth, and is never a
primary formation after the thirtieth year of life. Such tumors
lie beneath the covering periosteum, and at their free surfaces

Fig. 188. — Cancellous or Epiphyseal Osteoma, from the
Second Phalanx of the Thumb.

T, trabeculae ol bone-tissue, indistinctly lamellateil ; 3/, large and irregular medullary
spaces, containing blood-vessels and medullary tissue. (The latter shriveled, owing to the
circunistiince that tlie specimen was brought for examination in a half-dry condition.) Mag-
nified 100 diameters.

are usually lobular. They are either inclosed by a thin layer of
compact bone-tissue or by a layer of hyaline cartilage. They are
composed of indistinctly lameUated trabeculae of bone, contain,
ing regularly developed bone-coi-puscles, and inclosing medullary
spaces, which vary gi*eatly in size and are filled with meduUary
tissue and blood-vessels. (See Fig. 188.)

Formations closely allied to cancellous osteoma are the pro-
cessus supracondyloidei, which Hyrtl first described as congenital

490 TUMORS.

formations; they occur at the articular ends, mostly, of the
humerus and the femur, analogous to the processus trochleares
of some animals. To these may be added the bony formations
at the points of insertion of the tendons, muscles, and aponeur-
oses, which Virchow termed exostoses apophyficfe. They are
either directly connected with the bone, or take rise independ-
ently of it (so-called tendon bones). These bony structures orig-
inate, unconnected with inflammation, perhaps on account of an
excess of lime-salts in the organism. Maslowsky has succeeded
in producing calcareous deposition and ossification in the mus-
cles of animals, in the vascular system of which, for a certain
length of time, he had injected lactate of lime. Bony formations
in the dura mater, the muscles, and the lungs are products of
inflammation.

fbj Compact or ehurneal osteoma is a rare tumor; it occurs on
the bones of the face, the skull, the scapula, the pelvis, and the
phalanges; its favorite locality is the frontal bone. It has a
smooth or slightly nodulated surface, and very rarely attains any
considerable size. It is composed of a more or less regularly
lameUated bone-tissue, imitating in its structure the outer per-
ipheral layer of compact bone, and is scantily supplied -with
medullary spaces. These, on the surface of the tumor, are, as a
rule, large, and contain several blood-vessels; while the main
mass shows only irregular Haversian canals, which contain one
capiUary blood-vessel. Toward the point of attachment the com-
pact bone formation usually blends with the cancellous structure.
(See Fig. 189.)

The cement-layer of the roots of teeth not infrequently
develops into compact osteoma, which sometimes reaches a
considerable bulk. Tumors of the dentine are entirely dif-
ferent formations ; for their designation Virchow has pro-
posed the term odontoma. These are composed of dentine, with
irregularly arranged dentinal canaliculi, similar to formations
of secondary dentine and the so-caUed pulp-stones. (See chapter
on teeth.)

Bone-tissue is often found combined with other varieties of
tumors, such as fibroma, chondroma, myeloma, and it is asserted
that it also unites with cancer and forms the " malignant oste-
oid" of Joh. MiiUer. The terms employed to designate tumors
of these varieties are osteo-fibroma, osteo-chondroma, and osteo-
myeloma. In aU these instances the bone-tissue is unquestiona-
bly a secondary formation.

TUMOBS.

491

Psaninionia is tlie term applied by Virchow to a class of tumors character-
ized by the presence of ])eculiar corpuscles, which usually exhibit a distinct
concentric striation, or appear as nodular or rod-like masses. Virchow main-
tains that these tumors may be either homologous (benign) or heterologous
(malignant) — /. c, represent transitions into sarcoma. Virchow proposes to
call the corpuscles a rfunid — that is, sand-like; they are a normal feature in
the anterior portion of the glandula pinealis, where they form the acervulus
cerebri. Besides, they are met with in the cerebral and spinal dura mater,
especially in the Pacchionian bodies, and in the arachnoid. They are amy-
laceous corpuscles, infiltrated with lime-salts, although Virchow insists upon
their being different from the corpora amylacea on account of the blue stain
of the latter, shown when treated with iodine. Such corpuscles were found
also in enlarged hyperplastic lymph-ganglia. The tumors containing them
occur both in the brain-tissue and in its investing membranes, especially the
dura mater, in the optic nerve and its investments, and in the retina. (See
Fig. 190.)

Fig. 189. — Compact or Eburneal Osteoma, prom the Frontal
Bone op a Man.

i, lamellated bone-tissne, pierced by niertiillarj- spaces, M, which toward the periphery of
the tumor are large and contain several blood-vessels ; while in the more central portions of
the tumor the medullary spaces are reduced to irregular Haversian canals. Magnified 100
diameters.

The term "psammoma," applied to a tumor, is obviously superfluous, for
the arenoid corpuscles do not determine the nature of the tumor, which may
be a myxoma, a fibroma, an angioma, or a myeloma, consequently widely dif-
fering in pathological features. The arenoid corpuscles are secondary and
incidental formations in these tumors. The same holds good for pig-
mented tumors, which occur in rare cases in the pia mater, and are termed

492

TUMORS.

melanoma. The presence of pigment alone is not sufficient to characterize
the nature of the tumor. There is, however, no objection to calling a tumor
which contains sand-like bodies an " arenoid fibroma, angioma," etc., and a
tumor which contains pigment granules a " melanotic fibroma, myeloma,"
etc.

5. Myeloma or Sarcoma.

The special character of this group of tumors was first
determined by Virchow. He considers the structure to be con-
nective tissue in an embryonal or medullary condition, without
any epithelial elements, and thus sharply marked from cancer.
All later researches have corroborated Virchow's views. We

Fig. 190. — Arenoid Myxoma (Psammoma, Virchow) of the
Dura Mater.

r, trabeculiB of fibrous connective tissue, holding partly sessile, partly pediculated, arenoid
corpuscles, A, or elongated calcareous formations, C. Magnified 50 diameters.

define sarcomata as Virchow defined them — that is, connective-
tissue tumors, in which very little or no basis-substance is
developed. "We object, however, to the word " sarcoma," as this
means fiesJiy tumor., and would substitute for it the old term
"myeloma," — viz., medullary tumor, — as this accords better with
the histological features.

Virchow divided sarcomata into the following varieties:
(a) net-ceil sarcoma; fhj spindle-cell sarcoma; (c) round-cell

TUMORS.

493

sarcoma ; (d) (jiant-ccU sarcoma, and fcj melanotic sarcoma.
Billroth added another variety, the alveolar sarcoma. In ana-
lyzing the different varieties of myeloma, we are satisfied that
there are but two principal forms, which I propose to term
(a) (/loho-mi/eloma, corresponding to Virchow's round-cell sar-
coma ; and fhj sphulle-mi/eloma, corresi)onding to Virchow's
spindle-cell sarcoma. Both varieties arc sometimes found in
one tumor.

fAj aioho-mi/cloma is composed of medullary tissue, with
globular elements. (See page 147.) These contain single or double
nuclei, or they are divided into smaller plastids, evidently in the
mode of growth and multipli-
cation of the elements. Tum-
ors of this kind, as a rule, are
of a grajish-red or grayish-
yeUow color, containing a com-
paratively small number of
blood-vessels. Its sub-varieties ^^^^'^5^3t5^^^^.^^*^.,X'Lft^^\'s. C-

are:

faj Gloho-mi/eloma, composed
of large jjlastlds (large round-
cell sarcoma). These are sepa-
rated fi'om each other, either by
a nai'row rim of cement-sub-
stance or by a delicate fibrous
reticulum ; all elements, how-
ever, are connected by means of
delicate filaments. The nuclei
are large, and contain several
coarse granules — nucleoli. (See
Fig. 191.)

fbj Gloho-myeloma, composed
of small plastids (small round-
cell sarcoma), the structure
closely resembling the so-called adenoid or lymph-tissue. A deli-
cate fibrous reticulum holds varying numbers of plastids, which
are mostly solid, having the appearance of lymph-corpuscles,
some being surrounded by a finely granular bioplasson. This
form represents the "lymphoma" or '* lympho-sarcoma" of
authors. (See Fig. 192.)

fcj Glioma or glio-sarcoma. Virchow applies the term " gli-
oma" to tumors arising from the connective-tissue formations

Fig. 191. — Globo-myeloma, Com-
posed OP Large Plastids. From
THE Intermuscular Tissue of
THE Forearm of a Woman.

Till- globular, slightly flattened corimscles
are separated from each other bj' a scantj-
basis- or cemeut-substaiice. C, solid cord,
indicating a new formation or a retiogresaion
of a bloodvessel; C2, fully developed capil-
lary blood-vessel. Magnified UOO diameters.

494

TUMOBS.

of the central nervous system and the retina, without reference
to their intimate histological structure. Recently, efforts have
been made to remove glioma from the group of myeloma. Clin-
ical observation shows the extreme malignity of many of these
tumors ; microscopic examination shows their close relationship
to myeloma, and that a varying amount of fibrous connective
tissue may enter into their construction.

Glioma is composed of elements closely resembling those found
in the cortex cerebri and cerebelli, and those of the granular
layers of the retina. These elements exhibit comparatively large
nuclei, around which is a scanty rim of granular bioplasson.

In rapidly growing tumors the elements exhibit distinct
proliferation, and in many instances flatten each other. Between

■TS

Fig. 192. — Globo-myeloma, Composed of Small Plastids.
From the Testicle op an Adult.

T, transverse section of a semiuiferous tubule, toward tlie eiiirtidymis ; <S", myeloma of the
type of lyjnpli-tissue (adenoid tissue) ; TS, transition of tlie epitlielia into myeloma tissue.
(For high amplification of the same tumor, see Fig. 206.) Magnified 200 diameters.

them we see a delicate layer of cement-substance, traversed by
the connecting filaments. In the cement-substance homogeneous
plastids occur, indicating either development of glioma- or spindle-
shaped elements, which latter belong to the connective-tissue
frame. (See Fig. 193.)

fBJ Spindle-myeloma is composed of medullary tissue with
spindle-shaped elements. The difference between physiological

TUMOIiS.

495

iiu'diillarv and myeloinatous tissue is that, as a rule, in the latter
tlie buiulles of the spindh's are interlaein^ — i.e., course in differ-
ent directions, like interlacing fibrous connective tissue. Some-
times, however, the bundles take an almost parallel course, and
can be separated into radiating groups of spindles, the fascicular
spindU'-mijeloma (fascicular spindle-cell sarcoma of Virchow, fas-
cicular cancer of older patho-

-m

»\

GC

logists). The sub-varieties of
spindle-niyelonia are :

(a) tSijindJe-myeJotua, com-
posed of large plastids. These
are separated from each other
by a light rim of cement-sub-
stance or a delicate fibrous re-
ticulum, most distinct in trans-
verse sections of the Inindles.
The nuclei of the spindles, as
a rule, are seen as homogen-
eous and shining lumps, often
exhibiting marks of division
and multiplication. Between
the nucleated spindles there
are fusiform fields, containing
a finely granular or homogen-
eous mass; this indicates an
approach to basis-substance.
(See Fig. 194.)

(h) Spindle-nn/elonia, composed of small plastids, either interlac-
ing or taking an exclusively parallel course. In many instances this
tissue bears a close resemblance to non-medullated nerve-fibers.
Evidently, tumors composed of such delicate spindles are often
mistaken for true new formations of nerve-fibers, a neui'oma.
This variety of myeloma is not of infrequent occurrence in the
choroid, and often contains clusters of pigment which previously
belonged to the choroid or to the layer of pigmented endothelium
of the retina. Such pigment clusters, however, unless present in
a large number, will not justify a diagnosis of a melanotic mye-
loma. (See Fig. 195.)

(c) Spindle-net myeloma (net-cell sarcoma of Virchow). In
this variety spindles of varying sizes branch at acute angles, unite
and form a reticulum. The meshes of the reticulum are elongated,
and hold a slight amount of basis-substance and globular or

MS-

Fig. 193. — Glioma from the Orbit.
Recurrent Tumor after the
Enucleation of the Eyeball for
Glioma of the Retina.

M, glioma element witli several nuclei ; MH,
frroup of frlioma elements, sprunK from divi-
sion; OC, full}' developed glioma element; CF,
spindle-shaped libers between the groups of
glioma elements ; E, capillary blood-vessel.
Magnified 600 diameters.

496

TUMORS.

oblong plastids, which are apparently isolated. The more nearly
the reticulum approaches to a circular arrangement, and the
smaller its composing spindles, the more closely allied is this
variety to that of myxo-myeloma. Finally, all distinguishing

marks are lost, and spindle-net my-
eloma and myxo-myeloma blend
with each other. (See Fig. 196.)

The '■'' (jiant-cell sarcoma'''' of
Virchow cannot be considered as
a tumor sui generis, for the so-
called " giant-cells" never consti-
tute the entire mass of the tumor.
They are intermixed with fibrous

r;|;i??pfti'K";-^:^^vi4tp:

a

Fig. 194. — Spindle-myeloma, Com-
posed OF Large Plastids. From
THE Omentum of a Woman.

L, nucleated spiniUes cut longitudinally ;
O, spindles cut obliquely ; F, spindles cut
transversely. Magnified 600 diameters.

connective tissue, as well as
with fibro-myeloma, and are
more numerous and better de-
veloped the greater the amount
of basis-substance contained in
the surrounding tissue. As, in
our view, the multinuclear plas-
tids arise from a fusion of me-
dullary elements, whenever
there is a tendency to form ter-
ritories, usually of cartilage
and bone, it will be understood
from this fact that the malignity
of these tumors is very slight.

Their favorite site of growth is the periosteum, especially the
periosteum of the jaw-bones (so-called " epulis "), and a perma-
nent cure will ensue if the tumor is thoroughly extirpated. I
have examined several globo- and spindle-myelomata which had
grown from the maxillary bones, where very little basis-substance

Fig. 195. — Spindle -myeloma,
Composed of Small Plastids.
From the Choroid of an
Adult.

X, nucleated spindles cut longitudin-
ally ; O, spiudles cut obliquely ; B, pig-
ment clusters from the former pigmented
endothelium of the retina. Magnified
600 diameters.

TUMORS.

497

<'Ould l)t' found ; thtM-t^fore, tlioy wore dceidcdly malignant. In
tumors of Miis sort tlic multinuclear plastids were always scanty
and imperfectly developed — /. ^., composed only of clusters of
niedullai-y corpuscles. The <'.oinparatively })enif?n type of " epulis,"
however, is more common than tlie malignant. (See Fig. 197.)

Any tnijeloma, inchidhui the alreolar myeloma, may be the seat
of a more or less ahundant formation of pifpnent, and is then termed
melanotic myeloma. The pigment, therefore, is merely an inci-
dental feature of myeloma, but it is known to increase greatly
the malignancy of the tumor. The origin of the pigment was

Fig. 19G. — Spindle-net Myeloma, from the Subcutaneous
Tissue of the Leg op a Man.

<Sf, nucleated spinilles braiicliiiig and uiiitiiij? ; tlie meshes contain a finely granular myxom-
atous basis-substance, and G, ai>i)areutly isolated globular or oblong jjlastids. Magnified
600 diameters.

formerly attributed to extravasated blood. I have ascertained
that in such tumors a very profuse new formation of living
matter takes place, which causes the production of numerous
haematoblasts, — i. e., solid lumps of living matter, — which in their
earlier stages of formation, for reasons unknown, are supplied
with the coloring matter of the blood. (See page 98.) From
32

498

TUMORS.

these hsematoblasts, before their development into red blood-
corpuscles, arise the pigment clusters. The process can be best
studied at the border of melanotic myeloma of the choroid in the
region of the vitreous body. Here the haematoblasts originate in
the middle of the \dtreous body, being characterized by a globular
shape, luster, distinct yellow color, and theii' small size, as com-
pared with fully developed red blood-corpuscles, for which they

often are taken. How far the

:^'^^\\ / /

m^

y

k

htematoblasts participate in
the new formation of the my-
^ eloma elements I was unable
to ascertain ; but unquestion-
ably they are the source of
pigment in melanotic myelo-
ma. (See Fig. 198.)

Combinations of Mtjeloma.
Myeloma may combine with
any variety of connective tis-
sue- and epithelial tumors,
which means that a portion
of the tumor possesses fully
developed basis - substance,
while another portion has
but little or lacks it entirely.
A tumor with originally well-
developed basis -substance
may gradually change its
character, and in the por-
tions of later growth be with-
out basis-substance. With this
failure in the production of
basis-substance a more rapid gi'owth of the tumor ensues, and it
assumes a more malignant type. As before mentioned, such
tumors are clinically considered " dubious " in their nature,
although some of them are either of a marked malignant char-
acter, or become so in a relatively short time. According to our
nomenclature, the various combinations of these tumors are
termed as follows :

(a) Fibro-mijeloma, the "fibroplastic" tmnor, or '^ recuiTent
fibroma" of older pathologists. It consists of bundles of fibrous
connective tissue, between which are large numbers of usually
globular elements ; or the tumor originates from fibrous tissue, —

Fig. 197. — Fibro-myeloma, withMul-

TIXUCLEAR PlASTIDS. FrOM THE

Lower Jaw op a Young Mant.

M, group of medullary corpuscles approach-
ing the stage of indlffereuce ; G, multinuclear
plastid, so-called giant-cell. Magnified GOO
diameters.

TUMORS.

499

f. i., the derma of the skin, — and by de^'cos entirely replaces it.
The fibrous strueture of such tumors is sometimes very faintly
marked; but their eomparatively slight degree of malignity
is reeognized by the i)resenee of a finely granular basis-sub-
stanee between the homogeneous plastids, whieh, of the size of
nuclei, are scattered at regular intervals. Sometimes these
tumors are lobate or nodular, and covered with a i-ichly pig-
mented rete mucosuni (mole, miivus). With advancing age or

Fig. 108. — Melanotic Globo- and Spindle-myelojia of the Choroid,

L, group of globular pignientod plastids: F, delicate fibrous conuective tissue at the
periphery of the tumor ; jFf, lueiuatoblasts ; P, pigmeut cluster ; T', vitreous body. Maguified
600 diameters.

improper treatment they readily assume the character of malig-
nant myeloma. (See Fig. 199.)

(J) J Myxo-myeJoma is constructed on the plan of myxomatous
tissue — /. e., a delicate fibrous reticulum contains in its meshes
plastids in different stages of development ; but they are [far

500

TUMORS.

more numerous than in simple myxomatous tissue. Myxoma-
tous tumors, especially the so-called polj^oid tumors, often
exhibit some of the features of this type, indicating a rapid
growth of the tumor and its liability to recur after extirpation.
If the reticulum is very delicate, and
the inclosed plastids very small, not
exceeding in size the lymph-corpus-
cles, the tj^pe of a lympho-myeloma
(small globo-myeloma) is established,
which gro\\i:h is of intense malignity.
Myxo-myeloma, therefore, blends "wdth
the spindle-net myeloma, as well as
with the hTnpho-myeloma. (See Fig.
200.)

(c) Chondro-myeloma differs from
chondroma in the softness of its basis-
substance, while the plastids may a-

Fig. 199. — Globo-myeloma,
■mxH A Marked Formation
OF Basis-substance. From
THE Abdominal Wall of
an Adult.

C, capillary blood-vessel iu trans-
verse section ; A, artery iu transverse
section. Magnified 600 diameters.

exhibit the size and shape
of cartilage corjiuscles.
Many of the so-called '' ma-
lignant chondromata " prob-
ably are chondro-myeloma,
and I know this mistake to
have been made by good
pathologists. The term
" chondro - myeloma " may
also be applied to tumors
which, in a tissue showing aU the features of globo-myeloma,
contain islands of weU-developed cartilaginous tissue.

(d) Osteo-myeloma is a term used for the designation of
myelomatous tumors growing in the middle of the bone, or of

Fig. 200. — Myxo-myeloma. Recurrent
Pharyngeal Polypus.

B, portion of myxomatous structure ; P, portion
of myelomatous structure ; T', large capillar}- blood-
vessel. Magnified 600 diameters.

TUMOnS.

501

tumors in M'hioh within niyelonia-tissne now formation of l)ono
has taken phice. Tlie error resulting from such a nomenclature
is not gi'eat, as in many instances it is impossible to decide
whether the bone-tissue in the tumor is a remnant of the former
physiological bone, or whether it is newly formed, A gi-eat
irregularity in the size and the arrangement of the bone-cor-
puscles will favor the view of the bone being newly formed,

fit t ,

1^

Fig. 201. — Osteo-myxo-Myeloma, from the Hip-bone
OF A Girl.

T, trabeculse of newly formed bone, with larjre and irregular bone-corpuscles ; M, myx-
omatous tissue, changing to myeloma ; C, plastids, iuliltrale<l with lime-salts. Magnified 400
diameters.

and this view is strengthened if we are able to trace the new for-
mation of bone through all its stages, from the first infiltration
of plastids with lime-salts up to the appearance of trabeculae.
Besides, it is granted that the myeloma tissue (myxo- or fibro-

502 TUMORS.

myeloma) is not of a very malignant type where bone-tissue is
formed, though it is possible for the tumor to change to a more
malignant form. Myeloma, with numerous globular or spindle-
shaped elements, is, as a rule, deficient in new formation of bone.
The tumor the size of a child's head, from which Fig. 201 is taken,
for a number of years grew slowly, though steadily, while later
it increased rapidly to a fatal termination.

The combinations of myeloma tissue with other varieties of
tissue (lipoma, angioma, myoma, neuroma, and adenoma) will
be considered in the articles treating of these tumors. Here I
only mention that, according to Virchow, there also exists a
combination of cancer with myeloma — a view which I, from a
large number of observations, can corroborate.

Alveolar myeloma (Billroth) is of a dubious nature. Most
pathologists regard it as cancer, but it seems more correct to
class it among the myelomata ; for it shows all the clinical and
pathological features of such tumors — nay, it appears occasionally
as a secondary tumor after primary myeloma. A delicate frame
of connective tissue forms the alveoli, which are filled with glob-
ular, oblong, or irregular and usually nucleated plastids, very
loosely connected with one another — so loosely, that in sections
the alveoli appear incompletely filled. The plastids never reach
the size and the polyhedral shape of epithelia, so characteristic of
cancer; those nearest to the connective-tissue frame are pear-
shaped, being attached to the frame by a slender pedicle. I have
seen this variety of tumor in the groin, in the testis, the omentum,
and the liver ; in both the last-named positions the tumors were
secondary, and that of the liver was of a pronounced melanotic
type. Perhaps this tumor represents a transition of myeloma
into cancer, a transition which in the opposite way — cancer to
myeloma — is of more common occurrence. (See Fig. 202.)

Myeloma is a malignant tumor, and any portion of the con-
nective tissue of the body may serve as its starting-point. In
fact, this tumor has been observed in all parts and all organs of
the body, except in horny tissue. Contrary to cancer, it is often
a growth of childhood and youth, and may occur at any age. Its
malignity is intensified when the constituent elements are small,
the blood-vessels abundant, and the basis-substance scanty. The
presence of pigment, both in the fibrous and meduUary portions
of the tumor, greatly increases its malignant character. Not
infrequently local irritation, particularly injuries of all kinds,
can be traced as the exciting cause of myeloma.

TUMOIiS.

503

The cliiiiciil diati-nosis, in iiiaiiy instances, is possil)le when
there is a rapid growtli and hx-al nuiltiplication; often, however,
the tumor has all the appearances of a benign growth, Avhile
mieroseopie examination reveals its malignant nature. An error
in diagnosis may oeeur owing to the circumstance that myeloma,
upon approaching the surface, as a rule does not cause ulcera-
tion of the skin, neither are the neighboring lymphatics enlarged
or painful. Sometimes. myeloma appears in great numbers, almost
simultaneously in different parts of the body, and tumors, which
already have reached a certain size, may gradually disappear and
return again. Local recurrence after extirpation is a common

Fig. 202. — Alveolar Myeloma, from the Mesentery
OF A Young Man.

F, frame composed of a delicate fibrous connective tissue, carrying blood-vessels, inclos-
ing alveoli ; the latter contain C, the spindle-, pear-, or irregularly shaped plastids. Mag-
nified 600 diameters.

feature ; and so is multiplication, especially in the lungs, which
are sometimes found crowded with whitish, slightly vascularized,
tumors, the size of a poppy -seed, a hazel-nut, or a walnut.
The same may be found in the plem-a and the peritoneum. Mel-
anotic myeloma selects the subcutaneous tissue, mostly of the

504 TUMORS.

hands and the feet, as a point of departure, from which it gradu-
ally invades large portions of the surface of the body, in some
cases so rapidly that inflammatory symptoms are observed with
the formation of every new nodule. In such cases, the secondary
tumors in internal organs are either wliite or pigmented. The
patients die showing the symptoms of exhaustion (cachexia,
marasmus) or of septicaemia, in consequence of extensive gan-
grene of the tumors. Mucous or colloid degeneration n^ay also
occur, and this change renders the tumor much less malignant.

In the growth of myeloma, muscle- and nerve-tissue are trans-
formed into medullary tissue. If the tumor has originated in a
glandular organ, the epitheUa are also converted into medullary
plastids, and glands are either completely destroyed or partly
enlarged, and even newly formed. In the latter cases, peculiar
cauliflower -like vegetations are produced within the gland, owing
to the encroachment of the myeloma tissue. Under these condi-
tions, cysts are very common occurrences — f. i., in cysto-mye-
loma of the female breast or the ovary.

The Changes of Epithelia Produced by Growth of Myeloma.
By Eudolph Tauszky, of New York.*

It is kuown that myelomatous growths, which have originated either in
the cutaneous or subcutaneous tissue, and also those which appear in tissues
more deeply situated, as they approach the surface, sometimes produce ulcer-
ative processes in the integument. This always becomes attenuated before
the ulcerative process, often accompanied with inflammatory symptoms,
begins. After a certain time a loss of substance is observed at the most
prominent point of the tumor, which gradually enlarges ; and at its base the
tumor is seen as a reddish, slightly nodular, or even smooth mass. The idcer
produces, as a rule, a relatively small quantity of pus. Clinically, this is a
valuable diagnostic symptom of myeloma. Cancer invariably gives rise to an
ulcerative process in the skin, and the ulcers thus produced present uneven,
nodular, and irregularly gi-anulating sm'faces, yielding pus or ichor.

The question now arises: Wliat histological changes take place in the
wasting process of the epidermis f Of course, with the customaiy expression
of "fading or dying" of the epithelium only a clinical fact is recognized, and
the cause must be sought for in anatomical changes. At the same time, the
question may be answered : What changes does the epithelium of glandular
organs undergo when myeloma appears in them ?

The literature of the morbid gi-owths under consideration gives no satisfac-
tory explanation of the question. I therefore examined a number of myelo-

* Abstract from Dr, Rud. Tauszky's essay : " Ueber die durch Sarcomwiicherung be-
dingten Veianderungen des Epithels." Sitzunsber. d. Kais. Akadeniie d. Wisseusch. in Wien.
Bd. Ixxiii. The term " sarcoma " is cliauged into " myeloma," and that of " protoplasm " into
"bioplasson."

TUMOnS.

505

mata of the skin and glandular organs, with special reference to the behavior
of the epitlielium. My specimens were: (1 ) A myeloma about the size of a
child's fist, which was extirpated from the abdominal wall of a man fifty-five
years of age ; (2) myeloma gi-owths of the size of walnuts, whicli appeared in the
right gi'oin of a man sixty-nine years of age, and which, after repeated extirpa-
tions, were followed by numerous secondary myeloma nodules in the lungs;
(3) a myeloma of the testis of a man, aged forty-eight years, nearly the size
of a child's head; (4) a myeloma of the submaxillary gland, of a man aged

— />

Fig. 203. — FiBRO-MYELOMA FROM THE AbDOMIXAL WaLL OP

AN Adult.

P, papilla-, cut transversely ; i>, derma of sklu, with commencing transformation into
myeloma ; B, Ijlood- vessel ; S, rete mucosum. Magnified 200 diameters.

seventy-two years, as large as a chicken's egg; (5) myeloma nodules from
the liver of a man, aged fifty-nine, which occurred as a secondary gi-owth
after extirpation of a tumor of the eyeball, simultaneously with nodules in
the omenttim, the mesentery, and the walls of the small intestines. Among

506 TUMORS.

these were represented the varieties called * ' round-cell sarcoma " ; " spindle-"
combined with "round-cell sarcoma" and ''alveolar sarcoma."

The changes in the epithelium, which are induced by the growth of mye-
lomatous tumors, may be dixided into two groups. The first embraces the
purely inflammatory process ; the second includes changes that lead to the
production of myeloma elements from epithelium. No distinct boundary can
be di-a^vn between these two gi'oups ; for the changes observed in inflamma-
tion are like those accompanying the growth of tumors, inasmuch as in both
instances new formation of LiATug matter and production of new elements
results.

InHammatory changes. Specimens of the tumor (1) taken, from the integu-
ment near the ulceration show, with low power, that the epidermal layer was
thinned in several places. (See Fig. 203.) We could see that the pigmented
laver which constitutes the border nearest the connective tissue is in a con-

J

!>■

-^ti

Fig. 204. — FiBRO-JIYELOMA FROM THE ABDOMINAL WaLL

OF AN Adult.

J), bundles of connective tissue of derma in transformation to bioplasson ; T', blood-
vessel ; Pi, transformation of pigmented epitlielia into non-pigmented plastids; P*, epitheUa
■breaking down into pigmented lumps. Magnified 800 diameters.

dition of moderate " cell-infiltration " — that is, inflammation. The pigmented
epithelium is arranged irregularly, and is deficient in many places. Higher
amplification proves that the epithelium along the connective tissue is broken
up into elements, which do not differ fi-om those which originate in connect-
ive tissue ; only the pigment is a reminder of their origin, but the pigment in
this situation also gradually decreases as the inflammatory changes proceed
toward the epithelium. We meet with dispersed pigment granules, or groups of
such granules, apparently remnants of former epithelium, though the larger

TUMORS.

507

mass of pigment lias disappearod, perhaps by interference with the nutrition of
the granules themselves, whieh have not yet been entirely deprived of vitality.
Thus the ej)ithelium containing ]>igment is changed directly into indifferent
bioplasson bodies, from which, in turn, new elements arise. A real new
formation has as yet not taken place, but out of specific elements indifferent
ones have been produced by the formation of new separating lines of cement-
substance. (See Fig. L'04.)

Of particular interest is the condition of the hair-follicles and sweat-glands
which are imbedded in the tumor. Many hair-follicles, still holding hairs,
presented no material change ; in others, the hair was wanting and the con-
nective tissue of the follicle was transformed, in part at least, into the tissue
of the tumor. The elements of the outer root-sheath were divided into

Fig. 205.

■Surface op a Myeloma in the Right Groin
OF AN Adult.

M, partial wasting of cement-substance ; P, thickcnecl spokes (prickles) ; Si, spindle-
sliapeil plastids replacing the cement-substance ; S^, transition of the spindles into the frame
of the myeloma tissue. JIagnifled 600 diameters.

glistening, brownish-yellow lumps, whose groupings indicated their origin
from epithelia. .All these bodies were interconnected by fine filaments. The
ducts of the sweat-glands remained unaffected in most instances; but the
glands presented a conglomeration of bright-yellowish bodies, which by their
clustered arrangement indicated theii' origin from glandular epithelia. In many
tubules seen in transverse sections the central caliber was absent, and in some
places the bounding (structureless) layer of connective tissue was also gone,
and the tissue of the tumor came in direct contact with the changed epithelia.

508

TUMORS.

The skin covering the tumor (2) gave no ev-idence of ulceration, but was
merely stretched, attenuated, and reddened. In vertical sections peculiar
changes were noticed in the epidermal layer, which was reduced to a few layers
of epithelia of the rete mucosum. Near the surface several epithelia were
found coalesced, owing to the entire disappearance of the separating cement-
substance. The "prickles" traversing the lines of cement-substance were
well marked, even enlarged into oblong or square granules. In other places,
instead of these granules, spindle-shaped or oblong bodies were seen, repre-

FiG. 206. — GLOBO-m-ELOMA, Composed of Small Plastids.
TERSE Section of a Seminiferous Tubule,

Trans-

E, luicliaugeil columnar epithelia ; ES, comniencinj? trausforniatiou of epithelia into
myeloma elements ; -S', completed transformation of epithelia into myeloma elements ; i,
caliher of the seminiferous tubule. (For low amplification of the same tumor see Fig. 192.)
Magnified 800 diameters.

senting what Biesiadecki termed "migrating cells." Careful observation,
however, revealed that all of these bodies were connected -with the neighbor-
ing epithelial elements by means of delicate filaments. Such formations were
particularly numerous along the border separating the epithelia from the

TUMOliS. ' 509

inycloma-tissup, and raany of the spindle-shaped bodies merged into the fiVjers
separating the j^ronps of myeloma elements. Here, therefore, a new forma-
tion had arisen mainly from the '' i)riokles," wliile a direct transformation of
epithelia into myeloma elementsconld not be demonstrated. (See Fig. 'JOn.)

Tratisformatiou of cpillirliiiin into myeloma elements. The tumor of the
testis (;5) clearly exhibited the changes of the epithelia of the seminiferous
tubules caused l)y, the growth of the myeloma. Even low powers of the
microscope demonstrated that the myeloma tissue had in numerous places
pushed apart the seminiferous tubules, which in other places were entirely lost.
In a number of specimens, not only the boundary layer of the tubules — to-
ward the epididymis — was found to have disappeared, but the glandular epithe-
lium itself presented, in part at least, features identical to those of the tumor.
(See Fig. 193.) Higher amplifications exjjlained satisfactorily this peculiar
condition. The epithelium, in a transverse section of the tubule, appeared
in part to be well preserved, while in another portion of the same tubule
some of the epithelia exhibited coarse granules and solid lumps the size of
nuclei. A striking feature was that in one epithelium an unchanged portion
was found, and another portion was in the condition above described. Finally,
there were portions in which the epithelium was replaced by myeloma tissue,
in which its gradual stages could be traced. The increase of the living
matter tirst gave rise to the formation of coarse granules and new nuclei ;
next, new boundary lines originated within the epithelia, dividing them into
elements which bore no resemblance to the epithelia. Finally, the newly
formed elements were partly infiltrated with basis-substance, the perinuclear
form of which is characteristic of embryonal and lymph-tissue, as well as of
certain so-called " small-cellular" varieties of myeloma. (See Fig. 206.)

The result of these chaiujes is a real and complete transformation of the epithe-
lia into myeloma tissue. Here and there 1 met in this tissue gi'oups composed of
6-12 epithelia, which in all evidence were remnants of former glands or ducts,
but not a glandular new formation. In all specimens of this tumor the
spindle-shaped bodies which sprung from the cement-substance were in dis-
tinct connection with the reticulum of the myeloma tissue ; and all forma-
tions of living matter (granules, nucleoli, nuclei, spindles, and trabeculae)
were interconnected by delicate filaments. Even in the perinuclear, mucoid
basis-substance, in some places the bioplasson reticulum could be seen without
the aid of re-agents.

In the case (5)1 obtained a distinct view of the changes of the liver-epithelia
i)i growth of myeloma. Low powers of the microscope proved that the newly
formed myeloma nodules were separated from the surroiinding liver-tissue by
a tolerably thick capsule of connective tissue. Inside the capsule was a mye-
loma of alveolar structure ; outside of it tracts of liver-epithelia were com-
pressed, spindle-shaped, and running in a direction parallel to the surface of
the capsule. In some places the boundary line between myeloma and liver-
tissue was not sharply marked, but merely indicated by delicate bundles of
connective tissue. Probably, these were the myeloma nodules of later
periods. (See Fig. 207.) Here, in some places, the tracts of the liver-
epithelia were well preserved, while in other parts the epithelium was broken
up into globular or irregularly shaped bodies, which could only have origi-
nated from the living matter in the epitheUujn. These bodies presented all
the stages of transformation into myeloma tissue ; for, upon approaching the
myeloma nodule, they were seen in gi-oups, which, by virtue of their shape,

510

TUMORS.

must be pronounced myelomatous alveolar formations, separated from each
other by scanty connective tissue. Here, also, the endogenous production of
living matter in liver-epithelia had led to the formation of myeloma tissue.
The brownish color of the liver epithelium gradually faded into the grayish-
yellow of the myeloma nodules. In like manner, the gradual transformation
was indicated by the degree of carmine-staining, which had no effect upon
imchanged liver epitheliimi, but became more intense with the deviation of
the newly formed tissue from normal type of epithelium.

I can add that the myeloma of the submaxillary gland (4) presented, in
some portions, analogous appearances. In this tumor, too, the transforma-
tion of the epithelium of the acini of the salivary gland could be traced, step
by step.

My researches, in brief, gave the following results :

The myeloma growth, in its 2}>'ogress toward the epidermis, produces a change
in the living portion of the ejnthelium similar to that which is observed in the
superficial inflammatory processes of the skin. The cemen t-suhstance is dissolved ;
multinuclear l)iop>lasson bodies arise, and in them new lines of division originate,
producing indifferent elements, resembling those which spring from connective tissue.
New elements are also produced by a new formation of living matter, both within
the ejnthelia and in their cement-substance investment ; in the latter situation, of
course, from the filaments or '^jjricMes" of living matter. Such a new formation

Fig. 207. — Secondary Myeloma of the Liver.

C, connective tissue wliicli separates the myeloma nodule from tlie liver-tissue ; E, little
changed liver-epithelia within the myeloma nodule ; ,S, new formation of myeloma elements
from liver-epitheUa ; P, remnants of portal vessels. Magnified 6(10 diameters.

occurs in the epithelia of the external root-sheath and of the sweat-glands. The
attenuation of the epidermis is evidently caused by a gradual transformation of the
epithelia of the rete mucosum into myeloma tissue. In myelomata of glandular
organs, — salivary glands, testes, liver, — the new formation of bioplasson starts in
the epithelia with the appearance of new marks of division, and newly formed mye-
loma elements. The living matter of epithelium is directly converted into myeloma
tissue, ivith a partial or complete destruction of the epithelia.

TUMORS.

511

f). LiPo:\iA. Fatty Ti'mok.

Lipoma is composed of fat-tissue, exlii])itiii^ a lobular struet-
ure and traversed l)y septa of connective tissue, which carries
the blood-vessels. In the so-called w//, fdttjf tuinors the con-
nective tissue is scanty and the fat of a more oily nature, while
in tumors termed fibrous lipoma (formerly called steatoma) the
frame attains considerable development and the fat is more solid.
The fat-g'lobules resenil)le those of normal fat-tissue, and like
these sometimes contain needle-shaped crystals of ''margaric
acid." (See Fig. 208.)

Lipoma appears as a tumor sui f/eneris in the subcutaneous,
submucous, and subserous tissues, rarely in glandular organs.

Fig. 208. — Lipoma, from the Shoulder op a Man.

V, capillary blood-vessel in tlie frame of connective tissue ; F. fat-globules, pierced by
vacuoles, the latter being caused by preservation in chromic acid. Magnified 400 diameters.

In the subcutaneous tissue it occurs usually on the posterior
aspect of the body, and produces single globular, highly elastic
tumors, the surface of which appears to be lobulated to the touch,
and which, in different localities, have different degrees of con-
sistency. The tumor is usually quite movable, and sometimes
is very loosely attached to the body, pendent like a bag. The
covering integument is either unchanged or it is thickened and
pigmented, but may, as a rule, be raised in folds; it becomes

512 TUMOBS.

attached to the tumor only after injuries from without — f. i.,
friction of the clothing or long-continued pressure. Under these
circumstances ulceration even may be produced, which is char-
acterized by the offensive odor of discharge.

In the subcutaneous tissue both solitary and multiple fatty
tumors occur ; they may be circumscribed or diffused. Pedun-
culated and diffused fatty tumors are exceptional ; the latter are
of a softer consistency, and are attached to the skin by means of
dense, fibrous connective tissue.

Lipoma is painful only when nerve branches are involved in
the growth, and disturbance of functions is caused only by its
size and weight. The growth is slow but almost indefinite, as
there have been observed fatty tumors of twenty to thirty
pounds. The larger the tumor the more marked is its lobular
structure. Not infrequently calcareous deposition is found in
the connective-tissue frame, and occasionally, though rarely,
ossification.

Lipoma occurs combined with :

Hypertrophy of a finger, a toe, or the entire hand or foot ;

M^^oma, fibroma, and m^Tco-fibroma, producing tumors of
the skin, termed '' naevus lipomatodes " ;

Cavernous angioma (Billroth), when especially the veins are
ectatic in a high degree ;

Myeloma, usually myxo-myeloma of the subcutaneous tissue.

Peculiar branching growths of serous membranes, especially
of the knee-joint, which consist of delicate papillary vegetations
of connective tissue, whose meshes contain fat-tissue, are con-
sidered as formations of lipoma (1. arborescens). Localized,
diffuse new formation of fat occurs in the female breast, which,
on one or on both sides, may reach an enormous size and weight.

7. Angioma. Vascular or Erectile Tumor.

The characteristic feature of angioma is an abundant supply
of blood-vessels — arterial, venous, or capillary. This causes its
erectility — i. e., its swelling on a spontaneous engorgement of
the vessels. Such tumors ^neld readily to pressure, but as soon
as the pressure is removed they refill. In former times many of
these tumors were termed " teleangiectasis," as they were thought
to be due to a mere dilatation of the vessels ; now we are ac-

TUMORS.

513

(juaititt'd witli tlio fact that tlu' Ijlood-vcsscls are really new
t'oriiiatious. We ean (Hstiiif^uish three varieties of angioma,
according to the nature and distribution of the blood-vessels —
simple, lobular, and cavernous angioma.

((j) ^Sinij)lr <in(/ioi)i(i is, to a great extent, composed of newly
formed capillary blood-vessels, between which, in more or less
uniform distribution, is a var^-ing amount of fibrous or homo-
geneous connective tissue. The
coat of the T)lood- vessels is com-
posed of very large nucleated,
sometimes stratified, endothe-
lia ; niimerous tracts are solid,
and composed entirely of en--^'
dothelia (endothelioma). Both
in the endothelia and the con-
nective-tissue frame there are
indications of a new forma-
tion of red blood-corpuscles,
through the intermediate
stage of haematoblasts. (See
Fig. 209.)

fbj Lobular angioma is
composed of coils of large
capillary blood-vessels, held
together by delicate fibrous
tissue, while between the coils
this tissue is somewhat denser.
The lobate structure is some-
times marked to the naked
eye. In sections, the blood-
vessels are cut in longitudinal,
oblique, and transverse directions, and are found either empty
or filled with blood. The capillaries are connected with large
arteries or large veins, and the blood in the angioma may be
clinically recognized as being of either venous or arterial char-
acter. (See Fig. 210.)

fcj Cavernous angioma is constructed on the plan of cavern-
ous tissue — i. e., composed of venous sinuses, which lie close
to each other, separated only by walls of fibrous tissue, in
which are capillary blood-vessels, and sometimes bundles of
smooth muscle-fibers. The cavernous sinuses are filled with
blood-corpuscles, and the blood has in its clinical aspect a venous
33

Fig. 209. — Simple Angioma, from
THE Skin of the Forehead of a
Child,

X, longitudinal section of a capillary; -S",
soliil cortl of euilothclia; F, frame of a nearly
lioniogeneoiis connective tissue. Magnified
600 diameters.

514

TUMOBS.

character — i. e., is dark purple or bluish-red. The sinuses are
lined with a delicate layer of endothelia. (See Fig. 211.)

Angioma is a common type of tumors, and in most instances
is congenital. The simple and lobular angioma is located either
in the tissue of the derma of the skin or in the subcutaneous
tissue, and is in the latter situation abundantly supplied with
fat-globules. These tumors may occupy large districts in the
face (the so-called " fire-mole/' naevus vasculosus), or they may
appear in a number of smaller spots or elevations in different
parts of the skin. They may either remain stationary or grad-
ually increase in extent. Spontaneous cure is not an infrequent

Fig. 210. — Lobular Ajstgioma, from thk Orbit of a Child.

Xi, lobules composeil of coils of large capillary blood-vessels ; I, interstitial dense fibrons
connective tissue. Magnified 350 diameters.

occurrence. The lobidar angioma is, as a rule, more deeply
situated than simple angioma ; the tumor is to the naked eye
marked by shallow, irregular nodulations of the surface. Upon
invading the derma, the thinned skin covering it becomes im-
movable, and sometimes spontaneous ulceration takes place,
though the haemorrhage is rarely profuse. Cavernous angioma
is somewhat rarer, and appears either as a sharply eircum-

TUMORS. 515

SPi'ibod, as if onoystod, or as a diffuse tumor in tlic subcutaneous
tissue, in muscles beneatli the covering fascia?, in the liver, the
spleen, and the kidneys. It grows very slowly, and is often
painful. The pain may be continuous or ])e due to pressure
from without, and by rupture it may produce a dangerous
heemorrhage. Cavernous angioma reaches its highest develop-
ment on the extremities, on single fingers, or as numerous scat-
tered nodules, combined with consideral)le hyperplasia of the
derma. Occasionally, though rarely, angioma involves mucous
nu^nbranes. Several cases of angioma in the larynx have been
reported. In rare cases, all the soft tissues of an extremity are
transformed into the cavernous structure, with a gradual wasting

Fig. 211. — Cavernous Angioma, from the Basis op a Polypus Grown
AT THE Border of the Posterior Nares of a Child.

T, trabeculaj of fibrous connective tissue, lioUiing capillary blood-vessels ; E, endothelial
lining of the cavernous spaces ; B. red blood-corpuscles. Magnified 700 diameters.

of the bone. Primary tumors of this kind, grown from the peri-
osteum, and which gradually transform the bone into their own
tissue, the so-called '' pulsating bone-tumors," are rare. Angioma
combines with myxoma, fibroma, lipoma, and adenoma.

Angioma may he composed of Ji/mph-vessels, and is then termed
hjmph-angioma. There are two varieties : the simple hjmph-angi-
oma, composed of dense fibrous connective tissue, containing a

516

TUMORS.

varying number of lymph-vessels (Hebra), and the cavernous lymph-
angioma, composed of a large number of sinuous lymph-vessels
and a comparatively scanty amount of connective tissue. Simple
lymph-angioma is not of rare occurrence in the tissue of the skin,
and usually appears in the form of numerous hard, compressible
tumors the size of a lentil or of a hazel-nut. Cavernous lymph-
angioma is rare, and, as a rule, deeply situated in the subcu-
taneous or subfacial tissue, producing sometimes very large
tumors. Ulceration of these tumors occasionally takes place,
with a continuous oozing of honph. (See Fig. 212.) In macro-

FiG. 212.

•Cavernous Ltmph-angioma, from the Lateral
Region op the Neck of an Adult.

C, frame of connective tissue, of a homogeneous, waxy appearance and a liigh refractive
power ; -F, irregular reticulum of coagulated fibrine ; L, Ijmph-corpuscle. Magnified 500
diameters.

glossa, — the congenital enlargement of the tongue, of mainly its
anterior portions, — the mass consists of a fibrous connective tissue
with numerous sinuous Ivmph- vessels, and is, therefore, cavernous
lymph-angioma (Virchow). In some cases, cavernous blood-
angioma was observed. No new formation of striped muscles
was found in the tumor.

TUMORS. 517

Attention has recently been drawn to tumors which, in addition to well-
developed fibrous connective tissue, contain tracts or alveoli filled with finely
gi-anular polyhedral nucleated plastids, resembling the endothelia of blood-
vessels. Tumors of this structure are termed endothcUottut, and, as a matter
of course, are of a benign character. I have seen such formations in a
sebaceous adeno-fibroma of the scalp, in a lipo-fibroma of the skin of the face,
and in a tumor of the choroid the size of a sugar-pea. Endothelia are in their
structure identical Avitli the medullary corpuscles, representing the stage of
indi(l:"erence from which connective tissue and its derivations arise. In the
first instance, the endothelial tracts were like blood-vessels, but without per-
foration ; such tracts were also observed in the angioma of the skin of the
forehead of a child, illustrated in Fig. 209. In the second case, fat-globules
were found in the midst of the endothelia, and the conception was admissible
that fat originated from the endothelia, there representing an intermediate
stage. In the third case, alveoli were present, closely resembling cancer
nests. The differential diagnosis in such a case rests upon the regular arrange-
ment of the alveoli ; the lobular structure of the tumor ; the fully developed
fibroiis connective-tissue frame, which is of a nearly uniform width and scantily
supplied with blood-vessels ; the fine gi-anulation of the plastids and their pale,
finely granular nuclei. In such cases a positive differentiation between endo-
thelioma and epithelioma (cancer) seems difficult, if not impossible ; though the
clinical course of the benign endothelioma is altogether tlifferent from cancer.

8. Myoma. Muscle Tumor.

Tumors composed exclusively of striated muscles do not
occur; striped muscle-fibers are constituents of tumors, appear-
ing occasionally in the testis and the ovary, which also contain
remnants of other tissues, such as cartilage, bone, teeth, and
liau's. These are the so-called " dermoid cysts" — teratoid and
combination tumors. On the contrary, tumors composed of
smooth muscle-fibers are of frequent occurrence, always com-
bined, however, with fibrous connective tissue, constituting,
therefore, myo-fibroma or fibro-myoma. The organ which is the
most frequent site of tumors of this sort is the uterus, in middle
and advanced age, especially in the colored races.

Myo-fibroma of the uterus appears either beneath the mucous
layer, in the middle of the wall, or at the periphery of the uterus
(submucous, intraparietal, and subserous myo-fibroma), and in
almost every instance more or less smooth muscle-fibers are
found mixed "wdth the connective tissue. The latter tissue carries
the blood-vessels, which vary greatly in amount and sometimes
are so abundant as to justify a diagnosis of angio-myoma.
Fibrous tumors of the ovaries which I have examined exhibited
the same features. A subserous myo-fibroma of the uterus, under
the microscope, gave the appearances illustrated in Fig. 213.

518

TUMORS.

The bundles of smooth muscles are either scattered irregu-
larly throughout the tumor, always interlacing in different direc-
tions, as shown by sections, or there is a lobular structure when
nodules containing many smooth muscles, but little connective
tissue, are separated from each other by comparatively broad
layers of fibrous connective tissue. In bundles of smooth mus-
cle-fibers, cut longitudinally, the muscle nature of the fibers is
often unrecognizable, as they blend with those of connective tis-
sue, while in transverse sections of the bundles all doubts of the

L-^

iiMA.. . ... it:

Fig. 213. — Myo-fibroma of the Uterus.

L, bundles of smooth muscle-fibers cut longitudinally ; F, bundles of smooth muscle-
libers cut transversely; ^4, artery with a very broad muscle-coat; F, vein. Magnified 200
diameters.

muscle nature of the fibers are removed, owing to the presence
of abundant bioplasson and rod-like nuclei within the spindles,
separated from one another by a delicate fibrous perimysium.
One of the most striking features, in some cases, is the heavy
muscle-coat surrounding the arteries. (See Fig. 214.)

TUMOBS.

519

Myo-fihroma of the uterus is prone to fatty and calcareous
degeneration ; the former invades both the plastids of the con-
nective tissue and the muscles, the latter only the connective-
tissue frame. Moreover, there are cases on record where an
original myo-fibroma has changed into a malignant myeloma, or
even into cancer.

Myoma is a tumor of rare occurrence in the skin (growing in
the neighborhood of the nipple and in the scrotum), somewhat
less rare in the wall of the oesophagus, the stomach, the intes-

MlifiiAS

Fig. 214. — Myo-fibroma of the Uterus.

L, longitudinal bundles of smootli mnscle-fibers, not distinguishable from fibrous connect-
ive tissue; F, bundles of smooth muscle-fibei'S, cut transversely; A, artery with a heavy
muscle-coat. Magnified 500 diameters.

tines, in the wall of the urinary bladder, and in the prostate (in
the latter, hyperplastic myoma — Virchow).

9. Neuroma. Nerve Tumor.

The term " neuroma " can be properly applied only to tumors
which consist entirely, or at least partially, of newly formed
mediillated or non-medullated nerve-fibers; but it is doubtful

520 TUMORS.

whether such formations ever occur. Tumors containing nerves
have been observed most frequently on the spinal nerves, less
frequently on the sympathetic, and least frequently on the cere-
bral nerves. No positive proof has been given, however, that
the great ({uantities of nerves in these tumors are really newly
formed. If the internal perineurium — of course connective tis-
sue only — be augmented, the innumerable nerve-fibers are
pushed apart and may make the impression of constituting a
true neuroma. Glinsbiu'g, Wedl, and others have demonstrated
that, in the nodular nerve-gi'owths developed after the amputa-
tion of a limb, large numbers of the bundles of nerve-fibers, both
of the meduUated and non-meduUated varieties, were newly
formed. There are recorded cases in which one nerve produced
a number of tumors, which gave the formation a rosary-like
appearance ; in other cases, on a number of nerves in different
localities, tumors were found, and it is asserted that in such nod-
ules newly formed nerves were present in a large nutliber (mye-
hnic neiu'oma of Virchow). Some congenital tumors in the
sacral region have been found to contain a large number of
medullated nerves. Virchow observed teratoid tumors, composed
of nerve-tissue, resembling the gray substance of the brain.

Of still more doubtful occurrence are the tvimors composed
of non-medullated nerve-fibers, — the amyelinic neuroma of Vir-
chow,— who describes a case of reciu-rent ulcerative, and conse-
quently malignant, neuroma (''neuromatous diathesis")- Even
with our modern methods of investigation a positive proof of the
presence of non-medullated nerve-fibers is not easily obtained,
and many authors have doubted the existence of true amyelinic
neuromata.

Most of the nerve tumors have proved to consist, in addition
to a varying number of nerve-fibers, of the myxomatous and
fibrous varieties of connective tissue. Instead of using the term
" spurious neuroina," we shall designate such tumors as myxoma
or fibroma growing from a nerve, or if the tumor contains a large
number of nerve-fibers, we may term it neuro-myxoma, or neuro-
fibroma. Most of the so-called "painful tul)ercles" of the skin
also belong to this class. (See Fig. 215.)

Sometimes myeloma develops on or in a nerve, and, in
accordance with our terminology, such a tumor would be called
neuro-myeloma. The nerve-fibers, however, in the advancing
growth of the tumor are soon destroyed and transformed into
myeloma tissue.

TUMOliS.

521

The most important clinical sij?n of neuroma is its painf ulness,
which l)ears no relation to its size. Small tumors the size of a
lentil are sometinu's extremely painful, while lar^e ones, the size
of a man's fist, cause little or no pain. This diffenmce in the
amount of pain depends, doubtless, upon the fact that the nerve-
fil)ers in some tumors are quickly destroyed or transformed into
the tissue of the tumor.

10. Papilloma. Warty Tumor.

Warty tumors are combinations of connective and epithelial
tissue ; the former produces the finger-like, papillary elevations,
the latter furnishes the outer investment. The connective tissue

Fig. 215. — Neuro-fibroma of the Skix above the
Patella of a Woman.

K, remnants of niertullated nerve-fibers, -witli fluted outlines; 51, myeline drops, sepa-
rated from one anotlier ; V, capillary blood-vessel. Magnified 600 diameters.

is in its structure either fibrous or myxomatous, or a combination
of both, and, as a rule, supplied with numerous blood-vessels,
some of which are very large. Sometimes papillomatous growths
exhibit the structure of myeloma, either from the beginning or
after, by repeated trials of extirpation, considerable irritation has

522

TUMORS.

been set up. Under these circumstances, an originally benign
papilloma may pass into a myeloma, or a secondary change into
cancer may take place, both rendering the tumor malignant.
According to the nature of the connective tissue and the amount
of covering epithelium, we distinguish a horny and a myxoma-
tous papilloma as primary tumors.

(a) Horny 2^apilloma is composed of highly vascularized
fibrous connective tissue, producing branched, finger-like pro-
longations, and is covered by a stratified epithelial layer, usually
of considerable breadth. The deepest layers of the epithelia con-
tain a varying amount of pigment. (See Fig. 216.)

Fig. 216.— Papilloma of the Larynx.

E, heavy epithelial cover; P, papillary prolongations of connective tissue ; V, wide blood-
vessels. Magnified 50 diameters.

Warty tumors are of frequent occurrence on the skin, partic-
ularly of the fingers, and are often caused by a continued local
irritation of the part. They usually appear at the time of
puberty, and disappear spontaneously. They attain the largest
size in the region of the genitals, and are called in this situation
warty condylomata, their growth being always due to the local
irritation produced by the blennorrhoic secretion. They have
nothing in common with syphilis. Warty tumors are also of
frequent occurrence in the mucous membranes, especially of the

TUMORS.

523

larynx. The horns and rhin's of tlie skin of the face and the
scalp of elderly persons are papillomatous tumors with very long
and thin papillae. Warty tumors are known to be difficult to
cure, and with advaneini!; ai»'c sometimes to chanp^e into cancer.
(h) MjixotiiatoKs ixtpilloiiui occurs rarely cm the skin, hut more
frequently on mucous membranes. Such tumors consist of a
soft myxomatous connective tissue, always rich in blood-vessels,
and covered either with a comparatively thin layer of stratified
epithelia, or with a single layer of columnar epithelium. (See
Fig. 217.)

Fig. 217. — Papilloma of the Mucosa op the Uterus.

P', papilla covered by a single layer of columuar epithelia ; P'i, epithelial layer in top-
view ; ps^ papiUa deprived of its epithelial cover. Magnified 600 diameters.

To this class belong the papillomatous tumors, so-called " carun-
culae," of the female urethra, which are often extremely painful and
cause serious haemorrhages. They appear as dendi'itical, scarlet,
sessile vegetations, usually at the external orifice of the uretkra.
They occur, but are rare, in the mucosa of the uterus and of the
bladder. Llicke fii'st drew attention to the fact that the formerly
so-called " papillary cancer " of the bladder is originally a benign
papilloma, which in a secondary change may take on the charac-

524 TUMORS.

ter of myeloma or cancer. This fact was recently corroborated
by the accurate investigations of A. W. kStein. Papilloma of the
uterus may cast off portions of its substance with the menstrual
discharges. This occurred in the case of the woman who passed
the shreds illustrated in Fig. 217. Shreds of tissue may also be
passed with the urine, if papilloma of the bladder be present.
Papillary tumors combined with adenoma sometimes appear in
other mucous membranes, and they are always more difficult to
eradicate and more prone to change into a malignant type than
simple myxo-adenoma.

Microscopical Study of Papilloma op the Larynx.
By Louis Elsberg, M. D., New-York.*

All other laryngeal tumors together occur less frequently than papillo-
mata. Of three hundred and ten cases of intralaryngeal morbid gi'owths
that have come under my observation, I believe one hundred and sixty-three
to have been papillomatous, although the diagnosis, many times, was made
clinically only — /. c, without microscopical examination.

The tumor, the size of a coffee-bean, which is the subject of my study, was
removed by evulsion fi-om the anterior portion of the vocal band of a woman
thirty-six years old. In sections examined with low powers of the microscope
a central mass of connective tissue is seen, abundantly pro\dded with large
blood-vessels, mainly veins and capillaries, some choked with blood. Taper-
ing prolongations extend from this mass outward toward the periphery of the
tumor and the papilla?, and terminate in a large number of mimite, finger-like
ramifications. The central mass, with its prolongations, is invested with a
thick stratified epithelium, the lowest portion of which — /. c, the one nearest
the connective tissue — is a row of columnar epithelia, the main mass
euboidal, and the peripheral portion flattened epithelia. The latter exhibit
in some places irregular erosions, which produce a rather jagged outline.
Corresponding to the papilla?, the epithelial layers form rounded protrusions,
the valleys between the papillae representing the main mass of epithelial
structure.

Higher powers of the microscope (500-600 diameters) showthe fibrous con-
nective tissue in the central portion of the tumor to be made up of interwoven,
longitudinal, and transverse delicate bundles of fibers, the relatively thinner
bundles being nearer the peripliery. Most of the papilla? contain predominantly
the variety of connective tissue called myxomatous. Within the connective-
tissue bundles are seen numerous plastids, either single or in chains, either
roundish or oblong and fusiform, which are the so-called connective-tissue
corpuscles. In the myxomatous portion the fibers are more delicate than in
the fibrous, and are in many instances arranged in the shape of a delicate
net-work, at the nodes of which small, oblong nuclei are met with, while the
meshes contain either a finely gi-anular basis-substance or globular plastids of
varying size. The blood-vessels, which, as before mentioned, are very numer-
ous and very large, wind their way between the bundles, and some of them

* Abstract from tlic autlior's essay, " Archives of Laiyngology,!' vol. i., 1880.

TUMORS. 525

have a very narrow liut distinct niuscnlar coat. The endothelial coat of the
capillaries is well developed ; at some places the endotheliu are clustered
togetiier, with marks of division within the cluster, pointinjj to a proliferation
of the endothelial wall. Afost of the capillaries are surrounded by a some-
what denser fibrous connective tissue, even in the myxomatous portion of the
tumor. This layer of fibrous tissue constitutes an adventitia of the capillary
blood-vessels more distinct than is ordinarily met with in normal tissues.

The boundary-line between connective tissue and epithelium at many
places in the various specimens is sharply defined by a narrow zone of dense
fibers, identical with what has been termed the basement membrane ; at other
places, on the contrary, such a bounding zone is absent, and there is a gradual
transition of connective tissue into epithelium. In the latter eases the epi-
thelial bodies send ofifshoots into the reticular portion of the myxomatous tis-
sue, and it is impossible to tell where one terminates and the other begins.
Where a boimding layer of connective tissue exists, the columnar epithelia are
well defined ; where such a zone is absent they are ill defined, several rows
being sometimes piled up, each epithelium of a more or less fusiform shape
and very narrow. SiuTOunding each individual epithelial body, whether
spindle-shaped or well defined, and separating each fi-om all the others, there
are very narrow Light rims, pierced by extremely delicate threads. The main
mass of epithelium consists of cuboidal elements, which are polyhedi'al and
separated from each other by a light rim, — the so-called cement-substance, —
traversed by a large number of delicate threads or "thorns." Whenever the
razor has reached the sm-faee of a cuboidal element in front section, the epi-
thelium looks as if studded with short hairs or thorns. The cuboidal epithelia
nearest the outer limit exhibit the cement-substance and the thorns less
markedly, and in the layer of flattened epithelium at the periphery, cement-
substance and thorns are scarcely recognizable.

Most of the cuboidal epithelia hold in their interior a nucleus, the aspect
of which is, however, various. Not infrequently an epitheliiun has two nuclei,
of which one is finely, the other coarsely, gi'anular, or both may be coarsely
granular, differing from each other only in size and in the number of granules
they contain. Occasionally a nucleus constitutes an almost homogeneous
shining mass ; and, again, a mass split up into two or three relatively large
lumps or clusters of granules. Around compact nuclei a broad light rim is
sometimes visible, evidently a vacuole — i. e., a closed space filled with a
liquid. Large vacuoles in the centers of some epithelia are seen perfectly
empty, presumably because the nucleus that was in them has fallen out, or
been dragged out by the razor.

Instead of the so-called thorns seen in cement-substance, frequently slender
spindles are wedged in between two epithelia of a higher refracting power
than the latter. Or a shining spindle-shaped corpuscle lies close against one
wall of an epithelial body, while the cement-substance at the opposite side of
the spindle is slightly distended, and pierced by thorns running at right
angles to the spindle. In other instances, the thorns between two epithelial
walls seem to have run together into an almost square or oblong homogeneous
shining rod ; the cement-substance, more or less broadened, smTOunding the
rod on one or both sides and being pierced with other slender thorns. Again,
compact club-like or pear-shaped shining bodies, or a number of granules
in clusters of either a pear- or spindle-shape, are seen in the considerably dis-
tended cement-substance between two epithelia. These masses sometimes

526 TUMOBS.

reach, and sometimes surpass, in size that of large epithelial nuclei. Lastly,
pale or coarsely granular bodies are seen wedged in between two or three
neighboring epithelia, smaller in size than the latter, some being devoid of,
and some possessing, oblong nuclei. These various formations in the cement-
substance are found in large numbers in the vicinity of the papillae. They
occm- in the cement-substance of coliunnar as well as in that of cuboidal epi-
thelia. Very near the periphery of the tumor they are scanty, but absolutely
absent in the outermost layer of flat epithelium only.

With the highest powers of the microscope (1200 diameters) the fibrous
portion of the connective tissue is seen to be composed of extremely delicate
spindles, which are separated from each other by very nan-ow light rims,
analogous to those which we are accustomed to see in epithelial formations.
By closely watching these light rims we certainly detect in them slender
thi'eads, analogous to the thorns long known to exist in the cement-substance
of epithelium. The spindles themselves, representing what we call basis-
substance of connective tissue, are by no means homogeneous. In the thin-
nest layers of the bundles in the central portion of the tumor they exhibit a
delicate but distinct net-work, the threads of which are gi-ayish, the carmine
coloring being confined to the meshes. Interspersed between the spindles is
seen a large number of multi-caudate corpuscles of reticular structure, the
peripheral sprouts of which tend toward the spindles and inosculate with the
net-work of the basis-substance.

The peripheral portion of the connective tissue is, as has already been
stated, of a prevailing mj'xomatous structiu"e. Here the spindles constituting
the basis-substance, instead of being packed together to form bundles, are
associated in the shape of a coarse reticulum, holding numerous small corpus-
cles, mainly at the points of intersection ; but the larger meshes encircled by
the spindles also contain a niimber of similar corpuscles or else a light,
so-called mjTtomatous, basis-substance. High powers of the microscope reveal
a delicate net-work structure in the inside fields of the mj'xomatous basis-
substance, as well as in the encircling spindles, and this net-work is in unin-
terrupted connection with the corpuscles at the junction of the spindles and
those contained in some of the meshes.

The most peripheral portion of the connective tissue is in connection
with the epitbelimn. Where a shai-p line of demarcation exists, the highest
powers of the microscope reveal a single layer of connective-tissue spindles,
sei-Adng as a basis for the epithelia to rest on. This terminal stratum is in
close connection with the subjacent reticulum of mj-xomatous tissue and with
the capillary blood-vessels nearest the periphery. The blood-vessels not
infrequently approach the stratum so near that only a very narrow light rim
is left between their wall and the epithelium, and this rim is invariably tra-
versed by delicate gi*ayish filaments. On the opposite side the stratum is in
close contact with the peripheral threads of the net-work of fully developed
columnar epithelia. In the case of not fully developed epithelial elements, as
intimate a connection is established by shining homogeneous spindle-shaped
prolongations, which go fi-om the terminal stratum into the epithelial layer as
either an irregular reticulum or rows of filaments, arranged in a more or less
regularly vertical direction around a reticulated corpuscle, containing in its
interior one or more small, reticulated bodies of the aspect of nuclei. Thus,
such a reticulated corpuscle ^i. e., a not yet fully developed epithelium — is
inclosed in the spindle in a similar manner to that in which the cement-sub-

TUMORS.

527

stance suiToimds fully developed epithelia. The difference is that the spin-
dles are homogeneous and shining, of the same refracting power as the
gi-anules and threads of living matter, while the cement-substance is a pale
layer without any refracting power. Evidently, the spindles are compact
masses of living matter from which future epithelia arise, while the cement-
substance proper is a lifeless, horny material, containing only very little liv-
ing matter in the shape of the minute thorns that traverse it.

^Vlu're tliero is no sharp demarcation l)etween connective tissue and epi-
tlielium, even the highest powers of the microscope fail to demonstrate where
one terminates and the other begins. Only the presence of capillary blood-

FiG. 218.— Papilla, with Surrounding Epithelium.
Oblique Section.

a, bundle of fibrous connective tissue ; b, plastid between tlie spimlles ; c, myxomatous
connective tissue ; d, capillary blood-vessel cut across ; e, layer of connective tissue at the
base of tlie epithelia; /, spindle-shaped prolongations of the layer e, insinuated between
tlie epithelia ; (j, colunuiar epitlieliuiu ; li, medullary tissue, transition of connective tissue
into epithelium. Magnified 1200 diameters.

vessels furnishes some guidance for the determination of what is connective
tissue. (See Fig. 218.)

In the lower • strata of epithelia we most fi-equently meet with the
appearances in the cement-substance already described. The high power

528 TUMORS.

reveals in the cement-substance masses of living matter which tend unques-
tionably toward the formation of new epithelial bodies. The initial stage of
such formation is a growth and confluence of the thorns into rods or spindle-
shaped masses, which remain in connection with the neighboring epithelia by-
means of delicate threads. Such a change in the bulk of the living matter is
possible only after the liquefaction of the horny cement-substance. An increase
in the bulk of the thorns is invariably accompanied with a widening of the
space occupied by the cement-substance. Of course, the larger the formations
of living matter between the epithelia become, the larger must become the
space in which they are located ; and this enlargement often leads to the produc-
tion of bay-like excavations along the walls of contiguoiis epithelia. Such
excavations sometimes hold in-egular clusters of bodies, which in theu* optical
behavior are identical with the nuclei of epithelia generally. The preliminary
stage in the development of a new epithelial body is completed by the appear-
ance of a coarsely granular plastid, between the old finely granular epithelia
and the appearance of lines of new cement-substance around the newly
formed body. Changes similar to those that go on in the cement-substance
also occur in the interior of the nuclei. Nuclei of a dumb-bell shape, or two
nuclei within one epithelial body, have long been known as common features
in epithelia. They certainly seem to point to a multiplication of nuclei, but I
am unable to say whether they have anything to do with new formation of
epithelia or not. (See Fig. 219.)

As an addendum I may state that I have found, in microscopical sections
made from a papilloma of the penis, a so-called venereal wart, the same
characteristic features that I have described as belonging to papilloma of
the larynx.

A. Biesiadecki was the first to diaw attention to the presence of shining,
spindle-shaped bodies within the cement-substance of inflamed (eczematous)
skin, in which an active new growth of epithelia takes place ; but he claimed
that these spindle-shaped bodies came from the connective tissue. The most
recent writer, E. Klein, holds a similar opinion, for he describes and figiu*es
in his "Atlas of Histology," in the cement-substance of epithelium from the
tail of a tadpole, what he calls "branched cells" of connective tissiie, which
"are seen to extend with their processes amongst the epithelial cells." My
observed series disproves, of course, any such opinion.

What I liave proved in regard to the new formation of epithelia is that: (1)
Epithelium multiplies from medullary elements not distinguishable from those that
form connective tissue at the boundary hetween these two tissues; (2) epithelium
multiplies from the new growth of medullary elements which originate in the living
matter — the so-called thorns — ivithin the cement-substance.

11. Adenoma. Glandular Tumor,

Adenoma is composed of a myxomatous or fibrous connective
tissue, containing newly formed glands of either the acinous or
tubular varieties. Blood-vessels are found only in the connective-
tissue portions. The most characteristic feature of the glands is
the central caliber, which is invariably found in both the acinous

Tl'MOHS.

529

and tultnliii' toi-iiuitioiis. Ariiious n^lands, as a rule, are lined by
cuboidal or slioi't (•olumnar cpitlu'lia. wliicli are often sti-atified;
while tubular glands are lined by columnar epitlielia, which are
sometimes ciliated. The retrularity in the arraiif^ement of the
epithelia, their fine and uniform granulation, and the compara-
tively fint' ^n-annlations of the nuclei, are, in many instances at
least, distinjiuishing points for the diaj^uosis of an adenoma
under the microscope.

Fig. 210. — Cuboidal Epithelia, from the Neighborhood
OF THE Columnar Epithelia.

a, nucleus suriouiidert by a light space, a sc-called vacuole ; h, entity vacuole, nucleus
ilroppert out; c, epithelium with two nuclei; il, epitlieliuni with a briglit, homogeneous
nucleus; e, "thorns," or filaments of living matter in the cement substance; /, thorns in-
creased in size ; jr, enlarged thorns, united into a shining, spindle-shaped body; h, pear-shaped
body between epitlielia; I, rows of lumps and rods; k, medullary elements ; /, newly formed
epithelium wedged in between the old. JIagnified 1'20() diameters.

Adenoma is a common tumor, and occurs most frequently in
the following localities :

In the skin glandular new formations are observed, starting
from the sebaceous glands as sebaceous cysts, as molluscum seba-
34

530 TUMORS.

eeniii, and as milium. In some instances the ei)ithelia are trans-
formed into large, shining-, sometimes stratified, colloid corpuscles,
which were erroneously thought to be the infectious material
of the so-called ;»o////.sr^n« confaf/iosum, when a number of smaller
tumors form around a large adenoma. In milium the sebaceous
mass is inspissated, and by deposition of lime-salts is trans-
formed into cretaceous material. Tumors of this kind are
often inclosed by a thick fibrous connective-tissue capsule;
they are lial)le to become inflamed and ulcerated or to enter the
cystic degeneration.

In miicoKs membranes, most of the myxomatous sessile or
pedunculated so-called polypous tumors arc adenomatous (Bill-
roth), and deserve the name inijxo-adenoma. They occur in the
mucosa of the nasal cavities, the throat, the larynx, the tympa-
num, the rectum, and the uterus. In children, polypi occur most
frequently in the rectum, while in middle-aged persons they are
more commonly found in other localities. Their size varies
greatly. Those of the rectum sometimes grow to be as large as a
chicken's egg ; those of the uterus reach a still larger size. Ex-
ceptionally a marked papillary character is observed on the sur-
face. Rectal pohq^i show a distinct tubular structure in the
newly formed glands. Ciliated epithelia occur both on the sur-
face of the tumor and in the ducts of the glands, especially in
polypi of the nasal, laryngeal, and aural regions. Those of the
uterus also exhilut ciliated columnar epithelium, and are found
both in the mucosa of the cervical canal and in that of the uterine
cavity proper. In the latter situation they are often combined
with the lymphoid variety of myxomatous connective tissue, re-
presenting a benign type of tumors, though sometimes occuppng
quite extensive tracts of the mucosa.

A larger number of medullary elements in the myxomatous
connective tissue indicates a more rapid growth and greater
proneness to recurrence after extirpation. Exceptionally a trans-
formation into myeloma and cancer takes place, particularly after
repeated attempts at eradication.

In the female breast, adenoma of the acinous variety is also
of common occurrence, combined with myxoma or fibroma.
Sometimes the tumor is circumscribed and sharply defined from
the surrounding tissue ; at other times the growth invades one
or both mammary glands almost uniformly, which results in the
formation of very bulky tumors. If the connective tissue is pro-
fusely provided with medullary elements, the growth becomes

ri'MoHs. nm

an ((ih'ttoiiijiiloitKi, wliifli is offt'ii coiiiltiiicd witli cystic forma-
tions, and tliis condition was called ri/sfo-sarroiiKi iiKUintut . In sncli
tumors, well-marked cauliflower-like veg^etations ])rotrude into the
calibers of the newly formed dilated and folded glandular s))aces.
These veijetations were erroneously supposed to he inti'atilandular;
but they are obviously produced )\v an outj^rowth of the connect-
ive tissue lyiufj behind the glandular wall, which is usually ex-
trenudy vascular, aiul pushes and folds the wall into peculiarly
comi>licated prolongations. Adeno-jnyeloma of the breast some-
times breaks open and ulcerates, and the vascularized vegetations
may bulge out from the ulcer, with a simultaneous rapid growth
of the tumor. Nevertheless, this variety of tumor is known to
be comparatively benign, and to admit of a permanent cure l)y
extirpation.

In the fJn/roid body adenoma often occm*s, producing the
disease termed goitre. Either the alveoli, containing lymph-cor-
puscles and colloid material, are uniformly dilated — the so-called
parenchymatous goitre — or some of the alveoli, still lined by
the original embryonal epitheha, may become cystic and, in addi-
tion, be provided with numerous vascularized vegetations on the
inner surface of the cyst — cystic goitre. From the alveoli can-
cer may also develop as a primary or secondary tumor.

The major'dfi of ri/sts are secondary formations of adenoma.
"We sometimes observe cystic spaces in poh-jjoid tumors, and can
trace the gradual transformation of the glandular epithelia into
a mucous, colloid, or serous mass. As an intervening stage, a
sort of myxomatous tissue is observed arising fi-om medullary
corpuscles, into which the epithelia change before their liquefac-
tion. The closed cavity of the original alveolus is gradually dis-
tended and becomes a cyst, the inside wall of which is lined by
flat epithelia. (See Fig. 220.)

The sebaceous cysts and miliioji in the skin are invariably pre-
ceded by a stage of adenoma. In the subcutaneous tissue other
cysts may arise independently of epithelial growth — f. i., the
meJkeris, a cyst with honey-like contents; the htj<jroiii((fa, cysts of
the bursee mHcosee; and the so-called ganglia, cysts of the sheaths
of tendons. The cause of the appearance of cysts in such cases
as these is not known. Obviously, the cystic formations which
spring from an accumulation of blood, due to an extravasation,
cannot be considered as tumors in the strictest sense of the word.

Unquestionably, epithelial growth produces the so-called der-
moid cysts, wliieh are verv probably caused by anomalous forma-

532

TUMOBS.

tioiis in eml>ryoiial development — the formation of an imperfect
foetns in one perfectly developed, or intrauterine isolation by
constriction of parts of the embryonal body. These cysts contain,
besides epidermal tissue, hair-pouches, hairs, and also sebaceous
and sudoriparous glands, cartilage, bone, and teeth. Such tumors
were observed in the subcutaneous tissue, concreted with the
periosteum, in the orbit and its vicinity, in the testes and the
ovaries, rarely in other organs. Dermoid cysts have also been
observed in the lateral regions of the neck, and, as has been

Fig. 220. — Formation of Cysts in Myxo-adenoma.
Nasal Polypus.

M, uij'xoiuatoiis L-omiective tissue ; G, mucoid degeneration of the epitlielia ol an acinous
dand — a future cyst. Magnified 400 diameters.

suggested by Roser, are due probably to an imperfect retro-
gression of the gill canals of the embryo. Some of the cysts,
occurring at the base of the oral cavity beneath the tongue,
and termed ranula'^ are considered dermoid cysts, especially

wlifii tlicii" contents ;iiT di-y cpidi'iiiiiil oi- fatty, S('l)a<'(M)US
iiiasst'S.

('//■s/.s' of the interndl fcnm/c f/ftiifal orf/(iHs are of frequent
oocnirence, usually found in the ovaries, and presentiufj either
sinii)le cysts inclosed 1)V a comparatively thick capsule, <»r the
so-ealled parenehyiuatous cysts, which are (;oni})ined with ade-
noma or cancer (cysto-adenoma, cysto-earcinoma). Thc^ latter
varieties are rare in comparison with simple cysts. They are
composed of one sae only, or of a numl)er of partly closed, partly
confluent, cavities — the so-called multilocular cysts. Theii- con-
tents are either a serous or a viscid colloid liquid, with a varying
amount of l>lood. By a o-radnal chanji^e in the coloring matter of
the bh»od the contents show varying" shades of brown. An
admixture of pus renders the liquid cloudy, and by decomposi-
tion it becomes offensive and ichorous. Whenever pus-corpuscles
are present, as a general thing, we find large, coarsely granular
bodies, — the so-call(?d gorged corpuscles, — which, perhaps, are
epithelia in fatty degeneration ; while red blood-corpuscles,
swelled, and robbed of their coloring matter, appear as pale bod-
ies, containing only few granules ; these are the so-called Drys-
dale's corpuscles, which are not characteristic, by any means, of
the contents of an ovarian cyst. Cysts of the broad ligament
also can be traced back to their epithelial origin from the paro-
varies ; these single cysts almost always have very thin walls and
serous contents, without any combination with solid tumors.

In ovarian cysts the origin of the closed sacs from previous
glandular formations, in most instances, can be easily traced.
Usually, cysts originate in organs containing epithelia, — f. i.,the
liver, the kidneys, — though here the cysts are, in the majority of
the cases, ])roduced by an inflammatory process. The medullary
coi*puscles springing from the former epithelia are specially
endowed with, the capacity of mucoid or colloid degeneration and
the foiTnation of secondary cysts.

12. Carcinoma. Cancer.

Carcinoma is composed of connective tissue and epithelium,
the latter being arranged without regularity in the form of
alveoli, cords, pegs, or nests ; they are without glandular struct-
ure, and they show no regular central caliber. Cancer as a
primary tumor exhibits the following varieties :

534 TUMORS.

fa) In the variety termed scirrhxs, or hdrd cancer^ the con-
nective tissue is comparatively abundant and well developed,
either of loose, fibrous structure or compact, almost homogene-
ous. The epithelia are small, and arranged in narrow alveoli
or in tracts, irregularly distributed throuirhout the connective
tissue. (See Fig. 221.)

The connective tissue is fully developed, but scantily sup-
plied with blood-vessels. The small, polyhedral epithelia are
separated from each other by light. naiTOw rims of cement-
substance, but interconnected by conical filaments, in the same
way as normal epitlielia. The epithelia are clustered together in
small, irregular masses, and between the clusters and the adja-
cent connective tissue, in preserved sj)ecimens, a narrow space is

■z.'y

-CF

Fig. 221.— Scirrhcs, or Hard Caxcer op the
Female Breast.

X, alveolus, filled with epithelia : CF, connective-tissue frame, witli (CCJ clusters of
plastids, the connective-tissue corpiisclt-s ; IT, rows of epithelia, probably sprung from con-
nective tissue. Maguitieil 600 diameters.

often observed, containing granular matter or mucous globules,
which are considered to be the oifspring of eudothelia, lining the
inner surface of the connective-tissue cavity.

This variety is the least malignant and the slowest in its
growth. It appears most frequently as a primaiy tmnor in the
female breast, at the side of the nipple, often retracting the
nipple and producing folds in the skin. The comparative

ri'Mons. 5:55

density of its stnictmv, an occasional (lartin<<:, lancinating pain,
especially at ni«;lit, are its characteristic features.

This tnnioi- may exist for eight or ten years without any
rapid increase in size, and withont jjroducing much discomfort
to tin- patient. But after a certain time, almost invariably, the
gi-owth becomes more rapid, the pain more intense, and these
changes nuirk the transfornuition of the tumor into medidlary
cancer, with a rapid unfnvoral)le course and termination.

(h) In the variety called epithdiamd, the epithelia are found
lying in the connective-tissue frame as solid pegs or tracts or
nests, in the centers of which a concentric arrangement is ob-
served. The most central i)ortions of the epithelia often undergo
fatty degeneration, and prodnce shining, irregular masses of fat,
the so-called cancer-pearls. The connective tissue is either of the
myxomatous or fibrous variety, supplied with a moderate amount
of blood-vessels, and either exhil)iting fully developed basis-sub-
stance or a varying number of medullary or inflammatory cor-
puscles, replacing the basis-substance. (See Fig. 222.)

This tumor is of common occurrence in the skin and the
muc(nis membranes. Some of its varieties are eomi)aratively
slightly malignant ; for instance, the so-called /«/ cancer (rodent
ulcer) of the skin of the face, whose cancerous nature was recog-
nized thirty-five years ago by F. Schuh. The flat cancer produces
shallow ulcers, without marked vegetations ; the ulcer gradually
penetrates into the depth of the tissues, and destroys them,
including cartilage and bone. Though, owing to the presence
of the small epithelial nests, the cancerous nature of this tumor
cannot be doubted, it never produces secondary tumors in inter-
nal organs, but after a number of years kills by exhaustion.

The nodnJar form of epithelioma is most frequently observed
on the lips, the tongue, the anus, the external genitals, and the
vaginal portion of the uterus. It is rarer in the skin of the
extremities, the mucosa of the larynx, and the oesophagus.

Sometimes the papiUarij (canliffoicerj character of the epi-
thelioma is marked, especially in the skin of the face, at the
vaginal portion of the uterus, and in the mucosa of the bladder.
As before mentioned, it is highly probable that such so-called
papillary cancers have started as papilloma, and have gradually
changed into cancer. None of the sub-varieties of epithe-
lioma, though easily infecting the neighboring lymph-ganglia,
are particularly prone to produce secondary tumors in internal
organs.

536

Tr^fnns.

fcj The variety called m<(hil]((ni cY/y^r-p;- is the most malignant.
It shows the following features :

The epithelia are very large and irregular in shape ; sometimes
they are of a polyhedral form and partly nucleated, sometimes
homogeneous and shining. They exhibit endogenous multipli-
cation in the shape of so-called mother cells, and also multiplica-
tion effected through wedges which spring from the living matter

■f^5

'Mm

mM^'

Epitheliom.^ of the Prepuce.

E, eiiitlielial pegs : N, epitlielial nests, witli a coucciitik' airaiigeiiieut of tlie epitlu'lia in
Uie centers of the iiegs and nests ; P, so-called cancer-pearl in the center of the nests and
pegs ; C, connective tissue, crowded with medullary or intlamiuatory corpuscles. Maguitied
200 diameters.

in the cement-substance. The connective tissue is scanty ; it is
filirous in character, and incloses large and small groups of epi-
thelia in closed alveoli. (See Fig. 223.)

The characteristic feature of what we call meduUarv cancer

JIMOli'S.

537

is, therefore, tlie larue iiuiiihef of ejiitlielial foi-iiiiitioiis in coiii-
j>arisoii with the eomieetive tissue, the eoacse ^[•iiiiuhitioii of tlie
epithelia ^ivinj; them the appearaiKie of brif^ht, homogeneous
hunps — /. f\, solid masses of livinj^" matter, iudieatiuf^ an active
niorl)i<l «>:rowt]i of e[)ithelia. Tlie eompaet lumps of hioplasson
often apj)ear as medullary corpuscles ; the more rapid the j^rowth
of the tumor, the gi'eater is the increase of the corpuscles and the
nu)re nudijifnant the type of the growth. In the worst tumors
of this kind, Ave can harely trace under the mi(;rosco])e fully
developed, nucleated, polyhedral epithelia, arranged in nests ;
the nuiiii uuiss of the tissue is constructed of elements closely

Fig. 2l';;. — Medullary Cancer of the Parotid Glaxd.

Ji, rt'giilaily developed, polyhedral, nucleated epithelia, which ;it H,hy increase of tlieir
living matter, have become sliiuiuff and homogeneous ; M, medullary cor])uscles in a space
inclosed b.v livinj? matter (so-called motlier-cell) ; L, v^cuolation of epithelia; F, scanty con-
nective-tissue frame. Maftnified (jOO diameters.

crowded together, exhibiting all the features of medidlary cor-
puscles, and rendering the tumor a myeloma rather than a
cancer. Transition of cancer into myeloma under these circum-
stances is often observed. An originally well-developed scirrhus
may gradually assume the character of a medullary cancer, and
this the features of myeloma. In the clinical variety of carcinoma

538 TUMORS.

termed lenticular cancer (cancer en cnirasse, Velpeau), which
starts from a cancer nodule of the breast, and in a comparatively
short time invades all the soft tissues of the pectoral wall, the
shoulders, the upper extremities, we look in vain for the epithe-
lial eaucer-nests, the main bulk of the tumor being constructed
like a very malignant giobo-myeloma. Secondary tumors in
internal organs, chiefly the lungs and the liver, often exhibit
no distinct epithelial nests, but only the structure of globo-
myeloma.

Medullary cancer may appear primarily in any organ or tissue
of the body, although unquestionably, in the majority of cases,
it starts from organs which contain epithelial formations as
anatomical constituents, and are, therefore, glandular.

The localities where primary cancer most frequently develops
are : the female breast, the cervical portion of the uterus, and the
stomach. According to Vii-chow the order in which the organs
are invaded by malignant (jrowth. in general is the following:
Stomach in 34.9 per cent. ; uterus, vagina, etc., in 18.5 per cent. ;
large intestine and rectum in 8.1 per cent. ; liver in 7.5 per
cent. ; face, lips in 4.9 per cent. ; female breast in 4.3 per cent,
of the cases ; the sum total being 78.2 per cent, of fatal cases
caused by malignant tumors.

The classification of cancers is, as here shown, a simple matter,
but some pathologists are anxious to construct a large numl)er
of species and sub- varieties of cancer, with corresponding Greek
and Latin denominations. The term "plexiform" is suitable
for the designation of epithelial tracts branching and connect-
ing within the connective tissue. It may be stated as a general
ride that the larger the amount of connective tissue in a certain
bulk of the tumor, and the smaller the number of epithelial
nests, the harder will be its consistency and the less its malig-
nancy. On the contrary, the smaller the amount of connective
tissue, the larger the number of epithelial nests, the greater
will be its malignancy. Myxomatous connective tissue between
the epithelial nests necessarily lessens the consistency of the
tumor without increasing its malignancy.

An important point for the determination of the degree of
the malignancy of cancer is the presence of small, shining, globu-
lar elements in the connective tissue. Larger numbers of these
formations invariably indicate a rapid growth of the tumor, and
if occurring in a very large number they render the tumor a
myeloma. This condition is only found in the worst types of

Tl'MORS. .139

incdullaiy ciuu'cr. The piitlioloiii**;!! sitiiiificaiicc of tli<'se ele-
nu'iits (lilTcrs according to tlic views ot different auth<n's. Those
who believe the cancer epithelia to Ije an oft'spr-ing of physiologi-
cal epitlielia, and consider them to have a certain s])ecificity and
independence of connective tissue (Thiersch, Billroth, Waldeyer,
and others), assume that the medullary corpuscles in the cancer
frame are due to an inflammation reactive upon the growth of
the epithelia. While Virchow, who maintains a formation of
cancer e])ithelia from connective tissue, (Considers these corpuscles
as i)roducts of the '' connective-tissue cells." The following
article treats this subject more in detail.

The Origin op the Carcinoma Elements. By E. W. Hoeber, M. D.,

New-York.*

Regarding the origin of the cancer elements, pathologists nowadays hold
two essentially different views. Virchow first announced that "connective-
tissue corpuscles " might change into epithelial bodies ; while Thiersch, Wal-
deyer, and others maintained the view that epithelium is endowed with the
property of an independent development ; epithelia of pathological formation,
therefore, must always be the offspring of normal epithelia. The followers of
the latter view seek support in the history of development, and avail them-
selves of the theory of the germinal layers, as established by Remak, for the
explanation of pathological occurrences. To-day, arguments of this kind are
of little value. The assertions of the indeiieudeut action of the germinal lay-
ers fall to the ground in face of the fact that, before the appearance of such
layers, the germ is entirely composed of elements destitute of any peculiar
character, and it is not till later that special formations arise from these
elements.

We know that in inflammation the tissue retiu'ns to a juvenile condition,
and breaks down into the elements from which it had sprung. Elements pro-
duce their own kind only when in the embryonal condition. All observers,
notwithstanding our limited knowledge as to the cause of the gi-owth of
tumors, are agi'eed that the parent tissue, in which a primary new formation
originates, also retitrns to a juvenile stage or stage of indifference, in which it
is capable of producing new elements. These, in further development, give
rise to the characteristic tissue forms, which ai-e mainly of two kinds : vascu-
larized connective tissue and a vascidar epithelium. It has been maintained
that the epithelia are always offsprings of the upper and under germinal
layer, while endothelia originate from the middle germinal layer, especially
from the connective tissue. But even this apparently sharp distinction
between epithelia and endothelia will lose its point if we take into considera-
tion the fact that both epithelia and connective tissue originate from elements
which are morphologically identical.

Kiister has attempted to explain the development of cancers from endo-

^ Abstract of the author's essay, " Ueber die erste Entwickliiug iler Krebselemcnte."

SitziiiiirsliiT. (1. Kais. Akaileinie d. Wisscusch., 1875.

r)40

TI'MOBS.

thelia of the IjTnph-vessels, without, however, throwing light upon this ques-
tion. Eecently, also, A. Classen has endeavored to include the "migrating
cells " in the production of cancer, forgetting, evidently, the fact that
"migrating cells " are always elements in the stage of indifference ; that epi-
thelia, if fully developed, are not possessed of the capacity of migration, and
that no proof has yet been furnished of a new formation of tissue from wan-
dering corpixscles.

The subjects of my researches were cancers which had been removed from
the right parotid region, from the skin of the face, from the female breast,
and from the liver. The characteristic feature common to all cancers is the

Fig. 224.— Cancer df -ihl .->Ki.\ <>f the Parotid Kegion.

CE, large, nucleated cancer epithella, partlj- separated from each otlier bj' elastic fibers,
J?; C, unchanged fibrous connective tissue of tlie dtniia of tbe skin. Magnified 600
diameters.

epithelial new formation, the epithelial bodies, however, varj-ing greatly in
size. The largest I saw were iii the cancer of the parotid region. (See Fig.
224.)

The cancer epithelia represented polygonal bodies, separated from each
other by narrow rims of cement-substance having a ledge-like appearance and
traversed by delicate spokes. Sometimes I saw the peg-like or alveolar for-

iniitioMs. tillfd witli ;i ciditimiotis l;iy<'i' of liioplassoii, willi iiiicli-i iiii>n'il(l»'<l at
rt'^ular intervals. In siu-li layers — aiialo^xous to the so-called inyel(»i)laxeH
— the eeineut-substaiiee was partly or totally absent. A strikinj^ featnre was
that, in tnniors of slow fjrowtli, the epithelia were small aiul their f^ranules
and lumps of l)ioj>lass()n minute; while in eancers of raj>id {growth the epithe-
lia eontained eoarse granules and large nucleoli. In the cancer of the liver,
wliich liad increased rather rajtidly, the epithelia exhibited a very coarse
gi-anulation, and both within and between them were seen numerous lumps
of a homogeneous aj)pearance, without a reticular structure. Many of these
lumps in the alveoli liad no similarity whatever with true epithelial bodies.

The second constituent part of the cancer tumors — /. c, the connective
tissue — especially in those of comparatively rapid gi-owth, e.\hibited the so-
called "small cellular infiltration." (See Fig. 22.").)

'(Jl.ll \l / -ii /ii ^^Z Ml

Fig. 22.T. — Cancer of the Skin of the Parotid Region.

A. alveolus filled with epithelia; X, .so-called "small cellular" iiitiltration of the con-
nective tissue: A', foiniatious within the connective ti88\ie reseniblinj? ei))thelia ; V, blood-
vessel in transverse section. Magnified liOO diameters.

Examination with the highest powers of the microscope proved that this in-
filtration consisted of an accumulation of bright, globular homogeneous lumps,
on an average not reaching the size of red blood-corpuscles. Each lump was
almost constantly surrounded by a layer of bioplasson, whose granules were
connected with the lumps by means of radiating filaments. The lumps
assumed a %'iolet stain after treatment with chloride of gold. They exhibited
all phases of development, from compact masses to those which were pierced
with vacuoles, and finally to those showing nuclei, which were inclosed by a
thin shell and contained one or two nucleoli. Evidently these were bioplasson

542

TUMORS.

formations in a stage of indiflferenee, furnishing tlio material for specific
formations.

Now, what is the som-ce of these bodies '? We observe tliatthey appear first
in rhomboidal fields, corresponding with the territories of connective tissue.
At first one or two lumps only are visible in a territory ; later the whole ten-i-
tory is transformed into a coarsely gi"anular bioplasson mass, which contains
a varying number of globular formations. In a still more advanced stage the
territory is composed of polygonal plastids. Sometimes we see the connective
tissue between two alveoli filled with flat elements, some of which contain
large nucleoli. In such places it is apparent that a morphological difference

l"V'

■i^:

4,

i;,i /

||'#l\Y^Mi

Fig. 226. — Cancer of the Skin of the Parotid Region.

C, conuective tissue ; BE, epithelia, eitliev aiTanjreU in dosed alveoli or lyiiiir in the
interalveolar connective tissue. Masrnified 600 <lianietc'rs.

does not exist between the elements occupying the alveoli and those which
lie without much regularity in the neighboi'ing connective tissue. (See Fig.
226.)

In specimens from a so-called flat cancer of the skin of the face, I observed
that the connective tissue of the papillae in some places was almost completely
transformed into elements having the appearance of epithelia, and to such

TUMOBS.

^48

an extent Imd tliis elianj,'!- prof^rcssctl tluit only ;i delicate layer of filirous eon-
uectivo tissue was left uround the eonsi<lenihly dilated hlood-vessols.

Soiuetinios we see in tlio conneetive tissue, besitles the regular alveolai-
formations, spindle-shaped groups composed of snuiU epithelial elements ;
many of these grou))s prove to be on all sides incdosed l)y connective tissue.
Furthermore, epitlndial formations occur which are traversed by a branching,
shining, ehistic reticulum, as illustrated in Fig. 224. The elastic fibers are
arranged in such a way that the boundaries of the former territories of con-
nective tissue still remain recognizable, while in some places the elastic retic-
ulum replaces the epithelial cement-substance.

Finally, I would draw attention to rather common formations of the tran-
sition of indifferent bioplasson masses into distinct epithelial Viodies. On the

Fig. 227.— Ca^jcer of the Liver.

L, bioplasson luiiii' iu tlie middle of a rhomb of basis-substance of connective tissne
(Glisson's capsule) : R, multniuclear, rhoniboidal bioplasson formations, spiiuiir from coii-
lu-ctive tissue ; V, blood-vessel. MaKnifle<l 000 diameters.

one hand, small groups of a spindle- or rliomb-shape, composed of epithelia,
are imbedded in the fibrous connective tissue bordering the large alveoli.
(See Fig. 227.) On the other hand, the epithelial character of single elements
in rapidly growing cancers is not marked, as before mentioned.

From what I have seen, I cannot support the decided distinction hitherto
defined between epithelium and connective tissue. In the development of
conneetive tissue we often observe formations bearing all the featiu'es of epi-

544 TUMORS.

thelia — f. i., the so-called osteoblasts, arising from iiieduUary elements. In
both the epithelial and eonneetive-tissne formations, in certain stages of their
development, we meet with multinuclear bioplasson masses, in which in later
stages either cement-substance or basis-substance makes its appearance. So
far as the origin of different tissue forms is concerned, there is indeed a
marked similarity between them all.

I maixfa'ni fliat in develojyment ofcarcitionni epHlicl'uil foniiatioiisdppeav in the
coniicctire iissite which are indcj>endent of former f/hnidKhir forinatioiifi. The
proofs for this- ((ssfrfio)i are the closed xpindle-shaped sjxices of the contiectire
tissue, which co)it(t ill ri)itheli(i, and the epit]ieU(d formations which are traversed hij
branchinff elastic fliers.

The closed spaces of the connective tissue were supposed to be lymph-
spaces, the endothelium of which had been transformed into cancer elements,
or lymph-spaces into which cancer elements had immigrated. The first
mentioned concept of authors 1 need not contradict, for the endothelium is
admitted to be a formation of connective tissue. The second assertion lacks
foundation, for epithelia themselves do not migi'ate, and the assumption of a
transformation of indifferent migrating corpuscles into cancer epithelia does
not assist us in the explanation of the origin of cancer.

My second proof is, I think, a still stronger one. It is that elastic fibers
have never been observed in epithelial tissue, and, where they are present,
they prove rather the origin of the epithelia from former connective tissue,
whose territories are often bounded by elastic substance.

I, therefore, consider the epithelial formations in the midst of connective
tissue as the result of a rejuvenescence of the latter, such as we observe in
the inflammatory process. Under anomalous conditions the connective tissiie
returns to its medullary stage, which in sarcomatous gi'owths remains sta-
tionary. If, on the contrary, the development from the medullary stage
proceeds to the production of cement-substance, the medullaiy corpiiscles
assume the character of epithelia. The blood-vessels and their districts of
nutrition may also have an influence on this process of development of epi-
thelia, though the influence cannot be determined by observation, any more
than an explanation is possible where the infection of cancer is located,
which is transportable to neighboring lymphatics and to dift'erent and remote
organs.

Virchow's assertion that in certain conditions epithelimn arises from con-
nective tissue I consider to be correct, and I would widen this assertion by
adding that it is not the connective-tissue corpuscles alone which furnish new
elements, but it is the totality of living matter contained in the basis-sub-
stance which participates in the production of new epitlielial elements.

Local OrUjiu and Transmission. Malignant tninors frequently
arise from long-continued irritation or from traumatic inflam-
mation. Cancerous tumors, especially, can be traced to such a
source. After a number of years warts on the face, owing, perhaps,
to some slight injuries inflicted in washing, may ulcerate and
assume the character of cancer. In smokers, cancer of the lips
is often produced by tlie long-continued friction of jagged, bitten
pipe-stems. Cancer of the tongue often arises from ulcers pro-

TUMORS. 545

duced by the friction of decayed and broken teeth; also from
giimmy tnniors (Langenbeck). Persons addicted to alcoholic
drinkino- are more prone to carcinoma of the (eso])hapfus and
stomach tlian those of temperate habits. Men in advanced age
with a pliimotic prepuce are sul)ject to cancer of the penis ; and
those suffering- from piles may acquire cancer of the rectum.
Cancer of the breast and the litems, in many instances, can be
traced back to mechanical injuries. Ulcers of the skin, more
especially the so-called varicose ulcers, — nay, simple callosities on
the feet, — may take on a cancerous character. The primary cause
for the growth of cancer we do not know. Middle and advanced
age are most favorable for the growth of cancer — so much so,
that it is rarely observed under the thirtieth year ; it very sel-
dom occm-s in children. The older a person, the more liable is
he to cancer. This disease is observed only in civilized races ;
travelers report it is never found amongst savages. A com-
paratively good constitution is requisite for its growth; indi-
viduals of the so-called phthisical constitution, or those broken
down by chronic diseases, including syphilis, are not prone to
cancer, though a gummy tumor may exceptionally give rise to a
cancerous growth. Cancer and tuberculosis do not exclude each
other, as was thought to be the case by older pathologists. In
many instances we can trace the cancer as the primary disease,
whi(;h, by breaking down the constitution, causes tuberculosis of
different organs. I have observed eight cases of this kind.

Besides the local spreading of cancer, it almost invariably
invades the lymphatics within its range, which are also trans-
formed into cancer-tissue, and from which evidently starts the
general infection. Secondary cancer formations have been
observed not only in the lungs, the liver, or any organ, but
sometimes almost all the internal viscera are found crowded
with small nodules, identical in every respect to miliary tuber-
cles, the so-called " miliary carcinosis."

The Development of Carcinoma in Lymph-ganglia.
By a. W. Johnstone, Danville, Ky.'^

Dui-ing the winter of 1880-1, whilst working in Dr. Heitzmann's
laboratory in New-York, I examined four lymph-ganglia, three of which
showed the initial stages of the formation of cancer.

The first came from a man, forty-eight years old, who had noticed a few
small nodules on his prepuce. One of these was cut out and sent to the
laboratory for diagnosis. Upon its being pronounced cancer the penis was
* Priuteil in abstract from the author's mauuscript.

35

546 TUMOBS.

amputated. Six months later, two enlarged lymph-ganglia were found in the
right groin ; one as large as a hazel-nut, the other the size of a pea. Both
were extirpated, and, although two years had since elapsed, the patient was
perfectly well. The second ganglion came from a male inmate of Charity
Hospital, New- York City, aged forty-two. He had a cancer of the throat that
bled so freely that it necessitated the ligation of the right carotid. This was
followed by excision of the tumor and the removal of an enlarged lymph-gan-
glion from the posterior maxillary region. The man died shortly after the
operation, and at the post-mortem several abscesses were found in the lungs,
and yellowish nodules in the liver and kidneys, which the microscope showed
to be secondary cancer in its earliest stage of development. A male of over
fifty years furnished the third specimen. About a year before, he was operated
on for cancer of the skin on the leg. Shortly after, a number of new tumors
arose, and the lymphatics of the gi'oin began to swell. These new growths,
as well as the lymphatics, were removed and broiight to the laboratory. The
fourth case was a woman of unknown age, who was operated on, in 1875, at
the German Hospital of New-York City. A few indurated lymph-ganglia were
removed from the axilla. The last specimen I removed from the foot of a
lady. No enlarged glands were found, and she is now perfectly well.

The first three of these specimens contained all the stages of invasion, for
they not only showed the fully formed cancer-tissue, but also the perfectly
healthy adenoid structure. The fourth was composed of completed cancer-
tissue.

The transmission of cancer from a primary focus to the adjacent lymph-
ganglia is probably done by a transmission of its epithelia through the
lymph-vessels. This, we know, is sometimes done; for in case (1) I saw a
few epithelia scattered among the lymph-corpuscles of the cortical substance.
Their size and shape distinguished them from all siuTounding formations. Of
course, this fact will not support us in denying that the fluid portion of the
lymph coming from the cancer — the so-called cancer juice — may also trans-
mit the infection. We are sure only that cancer epithelia are lodged in the
lymphatic ganglia ; but we are equally certain that we cannot explain why
they or the juice can transform normal structures into cancer.

In the first thi-ee specimens I could trace, step by step, the whole of the
cancerous metamorphosis. The first stage I found in that part of the ganglion
where fibrous trabeculge separated the healthy from the diseased tissue. This
consisted of a melting down or running together of the elements and the for-
mation of large multinuclear masses — the so-called myeloplaxes. I have not
seen these formations in healthy adenoid tissue, but found a few small ones
in a hypertrophied tonsil. There is no doubt that they spring from the conflu-
ence of the lymph-corpuscles in all their different stages of development, as
well as from the myxomatous reticulum.

In the lymph follicle the corpuscles are connected with each other by deli-
cate offshoots of living matter, which pierce the separating layer of liquid.

We may infer that all that is necessary to the formation of a "myelo-
plax " is the fusion of the jelly-like intertrabecular substance. The process
of confluence of formerly separated corpuscles is shown in the earliest stages
of a growing cancer, and in the invasion of a lymph-ganglion its central por-
tion is generally fii'st involved. Frequently I found an interfoUicular string
completely transformed into a continuous bioplasson mass, but still retaining
its original shape. These masses are supplied at regular intervals with large

TUMORS. 547

{^lobular or oblong nuclei, which evidently are newly formed and have noth-
ing to do with the original nuclei of the lymph-corpuscles. I have shown (see
page 1(»S, Fig. 31) that the myxomatous reticulum holds a delicate net-work
of living matter, which, by the liquefa(rtion of the basis-substance held in its
meshes, becomes freed. This, most probably, is the process through which
the myxomatous frame-work is converted into the same mass as the corpus-
cles. These masses are coarsely gi'aimlar, wliich means that they are freely
supplied with living matter.

The next stage is the appearance of cement-substance in the shape of
straight, light lines, arising first in the middle of the bioplasson between the
nuclei. At first, the cement-lines are scarce and in many places traversed by
broad bridges of bioplasson. Later, the cement-substance assumes a regular
polyhecb-al shape, though it is always pierced by delicate spokes of living
matter, which are the inosculations of the reticula of living matter contained
by the neighboring epithelia.

The last feature is the formation of a frame of connective tissue which
divides the large bioplasson layer into smaller alveoli — the cancer nests.
The first trace of this formation is the appearance of delicate nucleated
spindles, which, by being split into smaller ones, build up the fibrous
Isasis-substance. At the same time the blood-vessels of these trabeculae
are formed. ,

Not infrequently the cancer nests in the middle of lymph-ganglia exhibit
concentric onion-like layers of epithelia, which in all probability arise from
the pressure caiised by the contraction of the surrounding connective tissue.
In the center of a nest we often see epithelia undergoing fatty degeneration.
Sometimes this has advanced to such an extent as to form a fat plug, which
is always surrounded by flattened horny epithelia. I found this concentric
arrangement in the first three cases. The fourth exhibited a fibrous fi-ame
inclosing irregular alveoli, filled with large and coarsely granular epithelia
without any regularity.

The essential point in the invasion of lymph-ganglia by cancer is, first, the
melting together of their components into large bioplasson masses. These in
turn, by the formation of a cement-substance, are split up into polygons,
which in groups become ensheathed by vascularized connective tissue, and
thus give rise to the cancer nests.

The study of the last ease, that of a rapidly growing primary cancer of
the foot, forced me to the conclusion that the same changes take place in the
formation of cancers in general. For along the edge of the fully formed car-
cinomatous tissue I found all the changes that I have just described. In this
specimen, the infiltration of the normal tissues with globular corpuscles was
unusually well marked. No doubt, the infiltration is itself a part of the can-
cerous metamorphosis, and it is only one of the steps of the adult tissue
toward a complete transformation into cancer tissue. So far as the micro-
scope can prove, this infiltration in its histological appearance is identical
vrith adenoid tissue, and the globular corpuscles are identical with the lymph-
corpuscles. In their retrograde change there is but one step toward the for-
mation of multinuclear masses.

Secondary Changes of Cancer. Both the constituent tissues of
cancer often undergo changes, which may either invade the

548 TUMORS.

tumor in part only or throughout its entire mass. Among these
changes I have observed the following :

faj Fatty MetamorpJiosis of the Cancer EpitheJia. This was
known to the older pathologists as a yellow reticulum, usually
seen in the central portions of the tumor. In the center of the
nests in the variety termed epithelioma the epithelia are often
transformed into fatty masses — the so-called cancer pearls. In
scirrhus the fatty metamorphosis may invade a large number of
epithelia, and in this way the tumor is robbed of its malignancy,
at least to a certain extent. As a change subsequent to fatty
metamorphosis, calcareous deposition occurs. This I found in a
cancerous growth, the size of a pigeon's-egg, which I extirpated
from the subcutaneous tissue of the lateral region of the neck ; it
exhibited calcareous depositions throughout all the epithelia to
such a degree that it could be cut only after treatment with a
chromic acid solution. Obviously, such a metamorphosis renders
the tumor innocuous.

fbj Waxy Metaniorplwsis. This I have repeatedly observed in
cancerous tumors. It transforms both the connective tissue and
the epithelia into a shining, homogeneous mass, and, if combined
with colloid degeneration, destroys the original structure, so that
the latter is recognizable only in some portions which are less
changed. Such a condition I have seen in a cancer of the parotid
gland. Sometimes shining and concentrically striated — so-caUed
amylaceous corpuscles — are present in the connective tissue
frame, and these may also become the seat of calcareous deposi-
tion (the so-called arenoid corpuscles of Virchow).

(c) Colloid Metamorphosis. It occurs chiefly in cancerous
tumors of the alimentary canal and the salivary glands, very
rarely in external organs. This change very much lessens the
malignancy of the tumor, although a recurrence has in some
cases been observed after extii'pation.

fdj Cystic Metamorphosis, which is closely allied to the col-
loid change. Both processes are considered in the following
article.

fej Pigmentary Metamorphosis. This is much rarer in carci-
noma than in myeloma, and gives the tumor a bro\\Tiish or bluish-
black color to the naked eye. I have seen but one case of a tumor
of this kind ; it grew on the right shoulder of a man, and soon
re-appeared after extirpation, which indicates that the presence
of pigment increases the malignity of cancer, as it does that
of myeloma. The recurrent tumor, in its uppermost portions.

TUMORS. r)49

exliibited the structure of cancer, with very lar^e polyhedi'al epi-
thelia and a comparatively scanty connective-tissue frame ; both
epitlielia and connective tissue contained a hir^e number of pifj^-
ment chisters. The lower portion of the tumor showed the feat-
ures of a pigmented myeloma, composed of large globular and
spindle-shaped elements.

The Development of Colloid Cancer. By H. G. Beyer, M. D.*

Epithelial formations exhibiting a central caliber, either acinous or tubular
in shape, must be considered as adenomata ; but such tumors, originally
benign, are very prone to change into cancer and thus become malignant.
When such a change occurs, the central caliber disappears, the connective
tissue becomes infiltrated with shining globular elements, and epithelia are
gradually developed therefrom.

It frequently happens that the original character of a carcinoma is, by
secondary changes, partly or entirely lost. In fatty, waxy, or calcareous
degenerations, the general eonfigvu-ation of the texture may be preserved.
Other secondary changes, on the contrary, entirely destroy the original archi-
tecture of the tumor, lea\4ng but few traces of its former primary character
behind. Colloid, adenoid, and cystic cancer may be classified with this group.
Colloid cancer is known to grow principallj' from the alimentary canal, the
walls of the stomach, intestine, and rectum being its most frequent localities.
Adenoid cancer is almost exclusively foiind in acinous glands, such as the
lachrymal and salivary glands. Cystic cancer is only an exceptional occur-
rence in different parts of the body, but is met with most frequently in the
ovaries. The specimen of this variety studied by me had formed in the liver,
secondarily to medullary cancer of the stomach, and was, therefore, a great
cui'iosity.

Of the colloid variety I had the opportunity of studying two cases : one
from the stomach, the other from the large intestine. They are tumors of
moderate consistence, infiltrating to a greater or less extent the walls of
the stomach, respectively of the large intestine and the neighboring organs.
The cut surfaces are of a pale graj^sh-yellow color, scantily supplied with
blood-vessels, and upon being scraped with the knife yield a jelly-like, semi-
translucent juice. In slight degrees of colloid change a precise discrimination
between this and medullary cancer of moderate softness is not possible to
the naked eye, while the liigh degrees of colloid degeneration, which lead
to the formation of very soft, jelly-like, often granular, tumors resembling
frog's spawn and quivering under the touch, are readily recognized.

The two cases of adenoid cancer which I have studied came from the sub-
maxillary gland. To the naked eye the appearances were not very character-
istic. Under the microscope they presented a coarse framework, composed of
bundles of connective tissue bounding a number of closed alveoli, and hold-
ing a moderate quantity of blood-vessels. The smallest of the alveoli con-
tained small but distinctly marked epithelia, while the larger ones held

* Extracted from the essay, " A Contributiou to the History of the Development of Col-
loid Cancer." By H. G. Beyer, M. D., Assistant Surgeon, U. S. 'S.—TJie Medical Gazette,
New-York, April, 1880.

550 TUMORS.

peculiar star-shaped formations with a central nucleus-like body, from which
a number of spokes were seen to emanate. These spokes, after traversing
the alveolus, blended with its wall. The largest of the alveoli showed only
traces of delicate branching fibrillas, tlie main substance consisting, as in
colloid cancer, of the so-called colloid mass.

Cystic cancer can easily be recognized by the naked eye. The tumor
shows a number of sacs, the size of a pin's head to that of a walnut, hold-
ing a sero-albuminous fluid. Under the microscope, epithelial nests were
found only at the periphery of the tumor. The cysts consisted of a wall
of connective tissue, and in the serous liqmd contained in their cavities only
a few plastids were found.

Vertical sections obtained from the thickened wall of the stomach affected
with cancer showed that the process of development had started from the
submucous and muscle layers. A number of epithelial nests, bounded by
smooth muscle-fibers, were found toward the periphery of the invading
growth. In the neighborhood of epithelial formations the connective tissue
had lost its fibrous structure and was transformed into finely granular
bioplasson, within which large, shining, yellowish lumps were irregularly
scattered. The bioplasson stage having thus been reestablished, the change
in the next consisted of an increase in size of the intersecting points of the
living reticulum ; these were transformed into medullary corpuscles, and,
after having reached a certain size, became polyhedral by flattening each
other, and in this manner were transformed into epithelia. The same char-
acteristic changes took place in the smooth muscle-fibers. They were first
transformed into rows of small, shining lumps of li\ing matter, and passed
by different stages of transition into epithelia. Groups of such epithelia
were smTounded by newly formed connective tissue, the framework of the
cancer.

In sections from the central portion of the tiimor all the stages leading to
a complete transformation into colloid cancer could be traced. "Within the
alveoli, bounded by newly formed connective tissue, a varying number of small
medullar^' elements and a limited number of epithelia were observed; the
remaining space was filled with a hyaline, apparently structureless, substance.
Many of the alveoli were entirely devoid both of medullary elements and epi-
thelia, holding only a homogeneous substance with remnants of li-viug matter.
Irregular clusters of epithelia could be seen here and there still attached to
the cancer frame. Some of the connective-tissue bundles were in part coarsely
granular and in part transformed into medullaiy corpuscles, giving rise to a
myxomatous basis-substance. (See Fig. 228.)

In the most advanced stages of colloid change the field was traversed by a
coarse, irregular reticulum of connective tissue, within which, besides a homo-
geneous substance, a more delicate fibrous net-work with remnants of epi-
thelia were observed. Epithelia from these portions of the timior, more
especially when but one was present in an alveolus, had lost their polyhedral
outlines, increased in size, as if by swelling, and had a globular or oblong shape.
Some of them had increased three times their natiu'al size, and presented
the appearances of pale, dropsical, partly nucleated bodies.

In specimens obtained from the colloid cancer of the large intestine it was
shown that the change had very uniformly invaded the entire tumor. Here
large alveoli, separated by coarse bundles of connective tissue, could be seen,
holding a very deiieate fibrous reticulum, %vith isolated clusters of epithelia.

TUMORS.

5ol

Tlit> rotu'ulum witliiu the ulvcoli w;is oitlior irrc^^uhir or, in certain ])l!icfs,
arraiif^od in a stai'-liko manner. In tlie center was a cluster of plastids, send-
ing out filamentous processes which blended with the wall of the alveolus.
The spaces between the radiating threads were filled with a finely {fi-an-
ular or homogeneous substance. In some alveoli, the reticulum presented an
appearance identical with that of mj-xomatous tissue. In addition to these
clusters of pale brownish-yellow opithelia, single, swelled, and dropsical-look-
ing ones were also present, with pale granular contents. The latter evidently
passed directly into the stage of myxomatous basis-substance. (See Fig.
220.)

Colloid cancer, consequently, is by no means a distinct species of cancer,
but merely the result of secondary changes taking place in an originally
medullary cancer. In the manner as cancer elements arise from medullary
elements may fully formed epithelia, imder certain imknown conditions,
retrogi'ess to mediUlary elements. Whenever this occurs, medullary corpus-
cles are transformed into a reticulum containing a jelly-like, homogeneous
basis-substance, with interspersed remnants of epithelia. In the same man-
ner, fully developed connective tissue may break down into medullary tissue.

rr-M

Fig. 228. — Colloid Cancer of the Stomach.

K coiiiiective-tissue frame; E, epitlielia of cancer in the meshes of the connective
tissue ; M, medullary corpuscles sprung from epitlielia ; C, medullary corpuscles chansins
to colloid substance ; a, alveolus tilled with a homogeneous coUoid substance, a few epithelia
left unchanged. Magnified 500 diameters.

from which epithelia are developed, and epithelia may rettuni to the medullary
stage from which connective tissue is developed.

With these observations in the mind, the formation of the so-called ade-
noid cancer, too, can be readily understood. Here the alveoli originally con-
tained cancer epithelia. These were changed into medullary corpuscles, from
which were developed both the star-shaped myxomatous reticulum and the
basis-substance filling its meshes. The center is occupied by either an
unchanged epithelium or a cluster of medullary corpuscles, which have arisen
therefrom.

Furthermore, we can understand the development of cystic cancer, the
smaller cavities of which are also very often traversed by a myxomatous
reticuhim. The degenerative change of epithelia into myxomatous basis-sub-
stance reaches here its highest degree, and leads to the complete destruction
of the mj-xomatous reticulum and to the liquefaction of its basis-substance.

552

TUMORS.

Cysts are the results of a coalescence of alveoli, which is due to an augmenta-
tion of serous fluid accumulating in the alveoli, finally rupturing them. As
regards their origin and development, there is no doubt about the identity of
medullarj", colloid, adenoid, and cystic cancer.

My investigations admit of the following conclusions :

1. Whereas cancer eplthelia are developed from medullary corpuscles, and
also connective tissue and smooth muscle-fihers, under certain morbid conditions,
break down itito these corpuscles, cancer may develop indirectly from connective
tissue and smooth muscle-fibers.

2. Cancer epithelia may return to the medullary stage and reproduce myxoma-
tous connective tissue.

3. The reticulum of livintj matter, present in myxomatous connective tissue, is
destroyed after the transformation of its basis-substance into colloid material.

Fig. 229.— Colloid Caxcer of the Large Ixtestixe.

F, connective-tissue frame, crowded witli medullary corpuscles ; E, epithelia of cancer,
partly or entirely fiUinfr the alveoli ; M, medullary elements, sprung from epithelia: .S, clus-
ter of medullary corpuscles, the center of radiating nucleated fibers, traversing the colloid
substance. Magnified 500 diameters.

4. Colloid and adenoid cancer originate from secondary changes of medulUiry
cancer; the changes consisting, first, in the transformation of the contents of an
alveolus into myxomatous basis-substance, next, in the further change of the latter
into colloid substance.

5. Cystic cancer is but the result of a more advanced stage of liquefaction of
the basis-substance of colloid cancer, accompanied by the formation of a connect-
ive-tissue sac — tlte wall of the cyst.

XIY.

THE SKIN.

THE apparently complicated structure of the integniment
becomes easily understood, if we keep in mind that there
are but two tissues entering the structure of the skin — viz.,
connective tissue and epithelium. The connective tissue pro-
duces the flat layer, called derma ; the epithelium covers the
derma on its outer surface. The boundary line between the
two formations is not even, but fluted, supplied with numerous
small protrusions of the derma, the so-called papiihe, the sum
total of which bears the name '■'papillary layer P The bundles of
the connective tissue everywhere run an oblique course ; they
are arranged in the shape of a coarse reticulum in the lowest
portion of the derma, whose rhomboidal meshes contain a Ydirry-
ing amount of fat-globules, the so-called suhcntaneous tissue. In
the derma proper, the bundles run in two main directions, inter-
lacing at acute angles, and thus producing a very dense felt,
which by l)eing tanned gives the leather. On the lowest portions
of the derma the bundles are relatively coarse ; they become
finer nearer the papillary layer, and in the latter very delicate
connective-tissue fibers are noticeable only, without a distinct
aiTangement into bundles. The epithelial formations on the
top of the derma, again, exhibit two layers : the lower one, that
nearest to the papillary layer, is living, and supplied with nerves,
the so-called rete mucosnm ; while the outermost layer is com-
posed of dry, horny epithelia, giving the formation called epi-
dermis. The connective tissue is supplied with blood-vessels and
lymphatics ; the epithelium lacks such formations.

554

THE SKIN.

(1) Suhcutaneons Tissue. The loose connective-tissue bundles,
traversing the subcutaneous tissue, are prolongations of the sub-
jacent membraneous formations, the fasciae of the muscles, the
aponeuroses, and the periosteum. The skin is firmly attached by
means of short and coarse bundles, at the extensor surfaces of the
articulations, in the groins, in the palms of the hands, and the

soles of the feet. Here a vary-
ing number of single or niulti-
locular spaces, containing a
sero-mucous fluid, are usually
found, — the so - called h urscB
mucos(e, — which are inclosed
by flat layers of fibrous con-
nective tissue and lined with
endothelia. In other localities,
such as the eyelids, the upper
portions of the auricle of the
ear, the penis, and the scrotum,
the attachment of the skin to
the subjacent fasciae is by loose,
delicate connective tissue, con-
taining no fat-globules. All
other fibrous tracts of the sub-
cutaneous tissue are more ob-
lique in their course, and so
extensible as to admit of a vary-
ing degree of pliability of the
skin ; they inclose rhomboidal
spaces, which contain more or
less numerous fat - globules.
The latter are grouped in lob-
ules, bounded by a delicate fibrous connective tissue, with a com-
paratively abundant vascular supply. This structure bears the
nsime pannici(li(s adiposus. (See Fig. 230.)

(2) The derma or cutis is composed of dense interlacing bun-
dles of fibrous connective tissue. Between the bundles we see a
continuous branching bioplasson layer, with a varjdng number
of nuclei, and sometimes with plastids, most of which are con-
nected with the rest of the free bioplasson. The bundles appear
very coarse in the lower, so-called reticular, portion, and are
bounded by distinct elastic layers or elastic fibrillee. These are
less marked as the bundles become finer toward the papilla?, tiU in

Fig. 230. — Subcutaneous Fat-tis-
sue, THE Fat havixg been Ex-
tracted BY Turpentine.

-B, bundle of flbroua connective tissne, car-
rying injected blood-vessels ; C, capsule of
fat-globules, with oblong nuclei. Magnified
500 diameters.

THE SKIN. r)r)5

the pajjillary layer tlicy disappear altogether. The bundles of
the di'niia have a certain regularity of ari'angement, as is demon-
strated l)v the researches of C Lan^ei-. This iiivestifxator
j)iuietuiTd the skin with a shoe-maker's awl, and after the with-
drawal of the instrument observed, in every instance, instead of
round holes, lonf>itudinal clefts, re^uLarly distril)uted over the
entire surface of the body. There are a few places where the
awl produces irregular jagged openings in the tissue of the
derma ; these are most marked in localities where the derma is
closely attached to the subjacent tissues. The same investigator
found tliat the striae of the skin of the abdomen and upper part
of the thighs, produced by over-extension, usually in pregnancy,
are caused by stretching in a horizontal direction of the bundles
of the connective tissue of the derma. The blood-vessels also
assume a horizontal coiu'se, following the stretched bundles. The
epithelial cover remains unchanged.

In the derma, the connective tissue is mixed with a varying
amount of muscles. The striped rarieti/ is seen in the skin of
the face and the lateral aspect of the neck, where the lowest
bundles connect with striped muscle-fibers, often in a reticular
arrangement. In many animals the derma has an almost con-
tinuous layer of striped muscles, the so-called panniculns carnosKS,
which enables these animals to produce voluntary movements
of the skin. Bundles of smooth musde-fihers are scattered
tliroughf>ut the derma, either in a reticular or fan-like arrange-
ment, or in the shape of single oblique bundles. The reticular
arrangement of smooth muscle-bundles presents itself in the
skin covering the nipple and its areole, the penis and the
scrotum. In the skin of the penis the direction of the muscle-
bundles is mostly circular, in the scrotimi antero-posterior. The
fan-like arrangement, and that in single bundles, occurs all over
the skin, the muscles, so-called arrectores pilorum, being every-
where in close relation to the hair-follicles. According to W.
Tomsa the connection between the smooth muscle-fibers and the
tissue of the derma is established by elastic fibers, which are
twined around the muscle-bundles. This relation is specially
marked in the arrectores pilorum. The connective tissue en-
sheathing the larger coils of sweat-glands exhibits smooth
muscle-fibers, which produce an almost continous layer around
the sweat-glands of the axillte.

The pjapiUary layer — /. e.j the outermost portion of the derma
— is composed of delicate fibers of connective tissue, not distinctly

556

THE SKIN.

interlacing, and freely supplied with small nuclei along the fibers.
The boundary line toward the ex)ithelium is slightly fringed, as
seen where the papillary layer is withdrawn from the rete
mucosum ; sometimes a hyaline, so-called structureless, layer may
be observed. (See Fig. 231.) The papillae are prolongations of
the derma, varj-ing greatly in size and shape in different localities
of the integument. The largest and most numerous papillae,
composed of a number of filiform elevations which coalesce
into a more bulky basis, are found on the palmar surface of the
hands and the plantar surface of the feet. In other places they
form small conical or blunt protrusions. The papiQae are every-

ilY^.^'^. \ J^ ^^ -^i^' ^^.^(

■ Fig. 231. — Papillary Later of the Skin of a Child.
Vertical Section.

The papilliE are artificially separated from the covering epithelium. £, epidermis ; JR,
rete mucosum; C, row of columnar epithelia nearest to the connective tissue; J", papillie,
composed of delicate fibrous connective tissue; L, longitudinal; T, transverse section of
bundles. Tlie blood-vessels injected. Magnified 500 diameters.

where arranged in rows, between which crossing furrows are
present, \'isible to the naked eye, produced by a peculiar arrange-
ment of the connective-tissue fibers, which is also marked on the
outer epidermal surface. The rows formed by the groupings
of the papillae are especially well marked in the palms of the

THE SKIN. 537

hands and tlu' soles of tlu' tVct, jLifiviiii^ rise to the ^aceful spiral
and concentric lines observed on the skin coverinj^ the last
phalanfjes.

In horizontal sections of tlie skin the papilUe appear as light,
circular, or oblong fields, marked by the presence of transverse or
obHcpie sections of tlie capillary blood-vessels in then- central
parts. The depressions between the papillae are ftUed with epi-
tlu'lia, which, being arranged in the form of an interpapillary
reticulum, have given rise to the inappropriate name " rete
mucosnm." (See Fig. 232.)

According to J. Collins Warren,* the papilliv are imperfectly
formed on the posterior aspect of tlie body. The follicles of the
lanugo hairs penetrate the superficial layers of the derma, the
sweep of whose fibers w^ould be unbroken were it not for the

Fig. 232. — Scalp op a Colored Man. Horizontal Section.

R, rete mucosuni ; Pi, row of columnar eplthelia, cut obliquely, supplied with dark-
brown pigment granules ; Pa, papiUa, cut transversely ; D, derma. MaRnified 500
diameters.

existence of a structure which connects the bases of the hair
follicles with the panniculus adiposus. This consists of a col-
munar cleft extending from the subcutaneous tissue in a some-
what oblique direction through the cutis to the base of the hair
follicle. This cleft is filled with adipose tissue, hence the term
"fat-column" is appropriate for its designation. Its long axis is
placed at a slight angle to that of the folUcle, and is nearly
parallel to that of the arrector pili muscle. The number of fat-
columns corresponds to the number of hairs. They are seen

* <'A Manual of Histology." By Thorn. E. Satterthwaite, New-York, 1881.

558 THE SKIN.

most distinctly in the thickest portions of the skin, but may-
be also found on the shoulders and arms, the breast, abdomen,
and the lower extremities, although sometimes only slightly
indicated.

(3) Blood-vessels. The arteries, which supply the skin, pene-
trate the subjacent fasciae and anastomose with each other above
the fasciae ; they are more numerous in the flexor surfaces of the
extremities than in the extensor, and than in the trunc. The
largest number is found in the palmar and plantar surfaces.
In accordance with the accurate researches of W. Tomsa, the skin
everywhere has three separate vascular districts, each of which
is supplied with its own arterioles and roots of veins. The
deepest is that of the subcutaneous fat-tissue ; the next in order
is that of the sweat-glands, and the most superficial belongs to
the derma, with its hair follicles and sebaceous glands. The
arterioles which supply the fat-tissue are numerous, correspond-
ing to the large number of capillaries ; those of the sweat-glands
surround the coils in a basket-like arrangement and empty into
two or three veinlets, one of which invariably runs upward along
the duct of the sweat-gland and anastomoses with veins of the
papillary layer. The artery, after supplying the above-named
formations, ascends to the papillary layer of the derma, and in
its course branches into capillaries which go to the hair follicles,
the sebaceous glands, and the papillae. Before reaching the
papillae, the arteriole splits into precapillary ramules, from which
arise the capillaries proper. These form loops which, as a rule,
are single, but in the largest papillae double, and unite into an
extended flat reticulum of a venous character. In portions of
the skin with large papillae there is a double layer of veins, the
superficial arranged in narrow and elongated meshes, the deeper,
on the contrary, in wide and more circular ones. These vessels
give rise to venous branches, uniting at acute angles into larger
veins, which produce arches and receive the veins of the sweat-
glands and the fat-lobules. The hair follicles have between the
two layers of the follicle wide, transversely arranged capHlaries,
which penetrate its inner layer also. In the upper portion of the
follicle numerous anastomoses exist with the capillaries of the
papillary layer, and in this situation arise the capillary loops for
the supply of the sebaceous glands. All these capillaries unite
into an irregular venous net- work, which is lodged in the exter-
nal layer of the hair follicle, and anastomoses freely with the
venous vessels of the papUlary layer. The papilla of the hair has

THE SKIN. 559

its (iwu {ivtcriolc, Avliidi braiiclR's into looped capillaries, empty-
m\f into tlie eoinnion Ncnons rcticnlnni of the hair follicle. The
vascular district of the i)apillai-y layer also fiii'uishcs the supply
for the muscles, the ducts of the sweat-giands, and the largci-
nerves. The muscle-layer of the scrotum only has an independent
vascular supply.

(4) Li/niph-resscls. Successful injections of the lymphatics of
tlie skin with colored liquids have proved that these vessels con-
stitute a closed reticular system, in two layers, interconnected
by oblique branches. The superficial layer of capiUary lymph-
atics is situated in the papillary portion of the skin, beneath the
superficial layer of blood-vessels. It is composed of ramules,
closer and narrower than those of the deep layer ; from it the
larger papilla^ receive blind offshoots or shallow loops. I. Neu-
mann describes lymphatic reticula around the hair follicles, the
sebaceous and the sweat glands. The wide lymphatic branches
which spring from the deep layer are destitute of valves, and
accompany the arteries producing capillaries twined around the
arteries. After having received the lymphatics of the subcuta-
neous tissue they are tm-nished with valves, and take their coui"se
in this tissue in large numbers, especially in the flexor aspects of
the extremities.

(5) JSferves. The skin is abundantly provided with both medul-
lated and non-medullated nerve-fibers, more especially in the palms
of the hands and the soles of the feet, particularly in the skin cov-
ering the last phalanges of the fingers and toes. The nerves
usually penetrate the derma together with the blood-vessels.
Some of the medullated nerve-fibers terminate in the subcutane-
ous tissue as Pacinian corpuscles ; others reach the upper por-
tions of the derma in bundles, where they produce a plexus.
From this plexus ai'ise branches for the nervous supply of the
papillae and the epithelial layer, some of which are medullated
and some non-medullated. The medullated nerve-fibers run to
the larger papillae, which, as a rule, are destitute of blood-vessels,
and terminate as a tactile corpuscle either in the papilla or at its
base, or even below its level. (See Fig. 233.)

The corpuscles of Pacini or Vater are ovoid bodies, discernible to the
naked eye, some of them attaining a longitudinal diameter of two mm. or
more. According to Genersich, they increase in size with advancing age.
They are attached to medullated nerve-fibers, and are composed of a number
of concentric, nucleated layers, more closely arranged at the periphery of the
corpuscle than toward its center, and freely supplied with capillary vessels.

560

THE SKIN.

of their own. Hoyer discovered, by means of silver-staining, a system of dark
brown lines, analogous to that in the endothelia. The medullated nerve-fiber
enters the corpuscle at one pole, and gradually loses its myeline investment,
while the myeline sheath is lost in the structure of the concentric lamellae.
The axis-cylinder terminates at the distal pole of the corpuscle as a simple
knob, or it bifiu-cates into two branches, each of which may also exhibit a
terminal knob. Around the axis-cylinder is found a gi'anular layer with nuclei.
Pacinian corpuscles are most numerous along the nerves of the fingers and
toes, less numerous in the palmar and plantar surfaces and in the \'ieinity of
larger articulations in the subcutaneous tissue of the nipple, penis, and
clitoris, also along the branches of sympathetic nerves, more especially behind
the pancreas, in the dura mater, the periosteum, etc.

The tactile corjmscles (Meissner's or Wagner's corpuscles) are
ovoid bodies, rarely exceeding 200 M in length, and composed of

Fig. 233. — Tactile Corpuscles in the Papill.e of the
Skin op the Finger-Tip.

iV, medullated nerve-fiber; r, tactile corpuscle; C, connective-tissue sheath ; P, pigment-
layer of the rete mucosnm. Magnified 500 diameters.

spiral fibers with small nuclei. Around them a somewhat denser
connective-tissue capsule is seen. One or two medullated nerves
enter the corpuscle at one pole, theu* myeline sheath being lost in
the fibrous mass of the corpuscle. The axis-cylinder divides into
a number of dehcate fibrillag, running with the spiral fibers ;

■JIII-: SKIS. 561

tlicii' ult iiiiMtc tci-iiiiiiiit ioii is not known. Soinctinics the tactile
eorpusch* exhibits deep fun-ows, indieatiiifj^ that it is composed of
several tactile l)uds (IMei-kcl). of two or more isolated ta(rtile cor-
puscles ai-e attached to one oi- two nerves (Oehl, Thin, and
othn-s). A. R. Kol)inson * maintains that the nerve does not ter-
minate in the tactile corpuscle, but passes on into the rete
miicosnni ; the axis-cylinder generally changes the direction of
its course after leaving the c()r])uscle, and tei-niinates between
the ei)ithelia.

X(>ii-iiii'<hill(if('(l inrre fibers are known to terminate in the
walls of the capillary l)lood- vessels of tlu^ pa})illary layer
(Tomsa), and in the rete mucosum (Langerhans, Flemming).
In the latter situation a delicate beaded reticulum of nerve
fibrillae can be brought to view, especially by staining with
chloride of gold, but the question is unsettled whether or not the
nerves enter the ei)ithelia. Tomsa noticed a delicate reticulum of
nerves around the coils of the sweat-glands; others have described
such a reticulum in the follicle and the papillae of the hair.

(6) TJn> EpithcTial Cover of the Iiife(/ni)ie)if. The outer layers
of the stratified cutaneous (epithelium are squamous, the middle,
which are the most abundant, cubodial, and the boundary, toward
the papilla\ consists of a single row of columnar epithelia. The
columnar and cul)oidal epithelia are endowed with vital proper-
ties, of which the flat epithelia ai-e deprived by their transforma-
tion into a horny material. The living portion of the epithelium
bears the name of rete mucosum, or rete Malpighii ; the horny
portion is the epidermis proper. Between these two layers
appears a narrow zone of nearly compact glistening epithelia,
running parallel with the surface ; Oehl has designated this layer
the stratum lucidum. It is sometimes well marked, especially
in vertical sections of the skin covering the palms of the
hands and soles of the feet ; sometimes it is not discernible. At
other times alternating layers are found, consisting of gi'anular,
niicleated, and of nearly homogeneous epithelia, destitute of
nuclei ; biit as these formations are not constantly present, we
are not justified in dividing, as some authors have done, the
epithelial cover of the integument into four or five distinct
layers.

The epithelia nearest the papillary layer are often indis-
tinctly columnar, and of a diffuse brownish color, holding more

* "A Manual of Histology," by Tliomas E. Satterthwaite. New- York,
1881.

36

562 THE SKIN.

or less pigment-p:rjiiniles. In the Caucasian race these are best
observed in the region of the nipple of the breast, the external
female genitals, the scrotum, and the anus. In the colored races
(see Fig. 232) the columnar epithelia contain numerous blackish-
brown pigment-granules, always scattered around the central
nucleus, which itself remains uncolored. Tlie pigment-granules,
by means of delicate filaments, are connected with the bioplasson
reticulum within the epithelia. Between the columnar, as well
as the neighboring cuboidal epithelia, the cement-substance is
invariably traversed by delicate transverse filaments, and con-
tains a varying number of homogeneous or granular bioplasson
bodies. These are growing epithelia, wedged between the older
formations, and interconnected with them by delicate offshoots.
Some authors have mistaken these lumps for connective tissue
or wandering cells.

The epithelia of the rete mucosum are irregularly polyhedral,
also supplied with a diffuse coloring matter, and distinctly nucle-
ated. The cement-sulistance shows the (ionnecting transverse
filaments, especially after treatment with chloride of gold. The
filaments (so-called thorns) are easily discernible in places which
were subject to a slight, continuous irritation (see page 323, Fig.
139). The cement-substance in this situation likewise holds
small, solid lumps of bioplasson, which are best marked and
most numerous in the localities exhibiting the thorns most
plainly. In the cement-substance of specimens successfully
stained with chloride of gold we find the beaded axis-fibriUae.
Toward the periphery the cuboidal epithelia are slightly flat-
tened and finely granular, which indicates that the epithelia are
gradually dying, though the vitality is usually retained by the
nucleus. There may be layers above the rete mucosum, com-
posed of flat epithelia, either homogeneous or distinctly nucle-
ated, and readily stained by carmine, which shows that they
are endowed with a higher degree of vitality.

The most external portion is composed of flat, imbricated
epithelia, which in the vertical section appear spindle-shaped.
Their horny nature is demonstrated by an irregidar contour, by
the want of granulations, and by the absence of a nucleus. The
nucleus may be found, however, in the lowest portions of the
horny layer, though it is often only faintly indicated. The
properties of life in these epithelia are gradually lost, and are
entirely absent in the outermost, flattened epidermal scales. We
know that the epidermal scales desquamate during life, but the

Till-: SKIS. 503

question how a lunv growth of cpithcliii goes on, rcphiciuf^ the
lost cpidcnnal seah's, is as yet not (luite sctth'il. In persons of
(lark coniph'xion the horny epithclia also cxliihit a diffuse yel-
h)W-l)rown (■oh)r.

(7) ItnpJttufdfioii of fill' Ildirs* If we imagine that the (;onneet-
ive tissue, together with the covering ej)itlielinni, were a ])liahle
sheet of chamois, for instance, and we prodnce a dei)ression of
this sheet with one of our fingers, the result will be a pouch, whose
innermost layers are epithelial, whose outermost layer is connect-
ive tissue. The e})i(h'rniis will cover the inner surface of the
])ouch, and now bear the name inner root-sheath ; next to this
will be a layer formed, by the epithelia of the rete mucosura,
which will be the outer root-sheath; the outside of the pouch
must be connective tissue, and will represent the foil trie. At the
bottom of the pouch will ])e a protrusion of the follicle, similar
to those on the surface of the skin, therefore connective tissue —
the pa pill a of the hair.

On our diagram slight alterations must be made. The epi-
dermis, which is composed of a large number of flat epithelia,
varying greatly according to the wddth of this layer, upon enter-
ing the pouch and becoming the inner root-sheath, will gradually
be reduced to a limited number of horny epithelia — in the middle
of the pouch to not more than two strata. Near the bottom of
the pouch the number of the epithelia again increases, the inner
root-sheath gains in width, and is composed of three or four
strata of epithelia which have lost their horny character, and
assume again the nature of bioplasson. The rete mucosum
enters the pouch in its full width, but gradually becomes thinner,
— namely, composed of a smaller number of epithelia, which
retain their original bioplasson character, — and at last, near the
bottom of the pouch, after being reduced to a single layer, com-
pletely disappears.

Imagine, now, that against the l)ottom of the epithelial pouch,
which runs in an oblique direction, corresponding with the dis-
position of the connective-tissue bundles, a pin is pressed and the
pouch turned upward again. This procedure, of coui'se, will
involve the inner root-sheath exclusively, and an elongation must
result of an epidermal character, agreeing with the main features
of the inner root-sheath. This elongation represents the hair.

* "A Contribution to the Minute Anatomy of the Skin." Read before the
American Dermatological Association, Newport, R. I., September 1, 1881.
The Chicago Medical Joiinial and Examiner, December, 1881.

564

THE SKIX.

The hair, therefore^ is n solid elongation of the holloir inner root-
sheath, and produced hy the inner root-sheath alone. The outer
root-sheath has nothing to do with the formation of the hair.
At the bottom of the pouch there is a knob composed of living
epithelia, resembling those of the inner root-sheath in the same
situation. This knob is called the bxlb of the root of fhf hair, and
directly surmounts the papilla of the haii*. Higher up the epi-
thelia again become horny, and enter into the construction of
the root and the shaft of the hair.

Imagine, lastly, that, on the side of the acute angle of the
obliquely implanted pouch, the outer root-sheath, which is, as

Fig. 234. — Diagram of the Implaxtation of the Hair.

E, epidermis ; RJtT, rete mucosum ; PL, papillary layer ; If>, inner root-slieath ; 0.5, outer
root-sheatli ; F, follicle ; Z>, derma ; M, arrector iiili muscle ; P, papilla of the hair ; B, bulb ;
C, cuticle ; H, root ; S, shaft of the hair ; SG, sebaceous gland.

said before, an offshoot of the rete mucosum. be pushed laterally
and downward by a pin, the result will be a third elongation,
produced by the outer root-sheath, a small pouch itself, bearing
the name sebaceous f/land. According to this diagram, the seba-
ceous gland is an exclusive formation of the outer roof-sheath, while
the inner root-sheath takes no part in the formation of the gland.
(See Fig. 234.)

TiiK SKIS. :,(;:,

The oxpliiiiation of tlii' iliiif^-ain is us follows: The fpidt-rinis, Imlging
downward, n>sults in the formation of the inner root-sheath, while the rete
muc'osuni, jjrolonged downward, forms the outer root-sheath.

The bundles of the connective tissue of the derma, wliich give an outer
investment to the pouch, composed of both root-sheaths, produce the follicle.
Its innermost portion exhibits cross-sections of smooth muscle-fibers.

The papilla of the hair is a product of the follicle. Around the papilla is a
knob — the bulb of the root of the hair — which continues into the root of the
hair — that part inclosed in the pouch; and the sliaft of tlif luilr — that part
standing forth on the surface of the skin.

The diagi-am shows that the inner root-.sheath, u])on approaching the
bottom of the pouch, becomes widened, and at the l)ottom of the pouch turns
over, thus first producing the bulb, afterward the root, and the shaft of the
hair itself. The innermost layer of the inner root-sheath, by tiu-ning over,
results in the fornuition of the cuticle, the single investing layer of both the
root and the shaft of the hair.

The figure demoTistrates, furthermore, that the outer root-sheath, upon
approaching the bottom of the pouch, becomes thinner, and perishes at last,
while on one side the outer root-sheath produces the pouch of the sebaceous
gland. Between the outer root-sheath and the follicle there is a homogeneous
layer — the so-called structureless membrane. The an-ector j)ili muscle is in
connection with the muscle-layer of the follicle and surrounds the bottom of
the sebaceous gland.

Our diagram serves as a key, which enables us to comprehend
easily all formations of the skin engaged in the construction of
the hair. (See Fig. 235.) The pouch, as a rule, has a funnel-
shaped widening on the surface of the skin, which is covered by
stratified epidermal scales. These scales are traceable in direct
union ^\'ith the inner root-.sheath, which begins on the so-called
neck of the pouch, being composed of two epidermal layers only,
and, in honor of the discoverer, termed Henle's sheath. Next to
the inner root-sheath lies the extremely delicate cuticle of the
hair, which ensheathes both the root and the shaft of the hair.
With higher powers we see on each hair fijiely serrated edges
— the slightly bulging edges of the cuticle. The hair is com-
posed of closely packed, horny epidermal spindles, which hold a
varying amount of pigment granules. The rete mucosum elon-
gates directly into the outer root-sheath, and this into the seba-
ceous gland. It is only the duct of this gland which is covered
by flat, horny epithelia, while the gland, as such, is composed of
cuboidal epithelia, like any acinous gland. The duct of the seba-
ceous gland, as a rule, empties into the funnel-shaped widening
of the pouch, in the space between the inner root-sheath and the
hair, or, more particularly, its covering cuticle. The outer root-
sheath is composed of several strata of epithelia, like the rete

566

THE SKIN.

mucosum itself. The strata are cul>oidal ei)ithelia, and it is only
the layer nearest the derma, or, more properly, the structureless
membrane, which is foi-med by columnar epithelium. The inner
surface of the structureless membrane, again, is covered by

Fig. 235. — The Upper Portion of the Hair-pouch
FROM THE Human Skin.

E, epidermis ; RM, rete mucosum ; PL, papUlary layer ; D, derma; F, follicle ; M, arrector
pili muscle; /S'G, sebaceous gland; OS, outer root-sheath; 7-S', inner root-sheath; C, cuticle ;
R, root of hair. Magnified 150 diameters.

extremely delicate flat endothelia, as was first demonstrated, by
the aid of silver-staining, by V. Czerny. These endothelia are

'/•///•; .VA7.V. r)()7

directly coiiiiccted vvilli the iuljaccMt colimiMai" cpitliclia l)y very
nmrked ])riekles and thorns. To tlie pi'esence of these thorns D.
Haijifht first di-e\v attention.

Tiie ])oneli of tlie sehaceous <;lan(l is nndcr the control of
tlie (irncfor pi/i iiiiisclr, which represents a flat, fan-like sheet,
wliose broad ends terminate in the papilhirv layer, whih' the nar-
row I'nd is inserted in tlie follicle of the root of the hair. No
doubt, the evacuation of the sebaceous gland is done by contra(;-
tion of this muscle-sheet. The fatty mass will be squeezed first
into the funnel of the hair-pouch, as a nde, and only from large
sebaceous glands directly to the surface'.

The lower extremity of the hair-pouch, in specimens taken
from the human skin, is readily understood if we have made a
study of the hair of aninuils, especially of those strong hairs on
the upper lip of kittens. It is, perhaps, for this reason that, after
many years' busy writing, not one author has given a plain
description of the relations. As a matter f)f course, the essentials
are identical in the hair of kittens and that of man, though the
former are, as a rule, plainer than the latter. (See Fig. 236.)

The inner root-sheath in its upper portion shows the light,
horny Henle's layer. In an oblique line there appear polyhedral
epithelia; in the upper portions pale and finely granular, with
indistinct nuclei ; deeper dowu, coarsely granular and slightly
elongated. This latter part of the inner root-sheath represents
what has l)een termed Huxley's layer. It is seen that at the bf)!-
tom of the pouch this layer turns over, surrounds the papilla,
and constitutes the bulb of the root of the hair. The epithelia
on the lower pei'iphery of the papilla are columnar, gradually
changing into the cu])oidal form, and farther up become elon-
gated, spindle-shaped. Lastly, they emerge into the horny
spindles which produce the main l)ulk of the hair. The bound-
ary line between the inner root-sheath and the root of the hair
is produced by a thin, apparently structureless, layer, outside
of which is the inner root-sheath, inside the cuticle of the hair.
The cuticle on the upper portion of the root is composed, as well
as on the shaft, of thin, imbricated scales, whose edges are slightly
elevated above the surface of the hau', and give the latter the
peculiar serrated appearance. Gradually, the epithelia of the
cuticle of the root assume a columnar shape and become nucleated.
At the height of the bulb these columnar epithelia are very large,
pale granular, and supplied with large and distinct nuclei.
Their characteristic row runs in the middle, between Huxley's

568

THE SKIN

layer and the bulb, and at last blends ^^'M\l the euboidal epi-
thelia of both formations. Outside of the eutienlar row there is
another thin layer of pale, flattened epithelia, which evidently
corresponds to the innermost structureless layer of the inner root-
sheath. The middle portion of the bulb is often filled with

afS.

Fig. 236. — The Lower Portion of the Hair-pouch, from
THE Lip of a Kitten.

F, follicle : T, transverse sections of connective-tissue bundles of derma i 3/, aiTector
pili muscle ; IS, inner root-slieath ; 0-5, outer root-sheatli : P. iiapilla ; C, cuticle ; R, root of
Uair: II, hyaline, or so-called structureless, membrane, Majruitied SOO diameters.

globular, indifferent, or medullaiy corpuscles, which hold a xsry-
ing amount of pigment, and fill also the central portion of the
root, the so-called medullary space, which even in strong hairs

Till': sKix. :m

may l)e ahsi-ut. Tlu' iippi-r portion of the ouUt root-sheutli is
c<)nii)()sed of stratifit'd cpitlu'lia, tlie most external layer >)ein«:f
distinctly coluiiinar. This ('<»liimTiai* row is the last one left, as
the outer root-sheath approaches the region of the bulb, and,
gradually becoming thinner, is at length entirely lost at the
height of the ])ull), whose formation it does not enter at all.
The boundary line Ix'tvveen the outer and the inner root-sheath
is marked by the presence of a so-called structureless or cutieulai-
membrane. External to the outer root-sheath we find the follicle,
a connective-tissue fornuition, with interspersed circular muscle-
s])indles, connected with those of the arrector pili muscle. Be-
tween the follicle and the outer root-sheath there is usually a
broad homogeneous layer, which can be traced around the bulb
of the root and the papilla of the hair.

The papilla of the hair is composed of a delicate fibrous or
myxomatous connective tissue, freely supplied with plastids
having the appearance of spindle-shaped nuclei, and traversed
by a number of capillary blood-vessels. The apex of the papilla
in our specimen is not distinctly sex)arated from the epithelia of
the hair. The line of demarcation, however, as a rule, is distin-
guished by the presence of a row of columnar epithelia or by the
medullary corpuscles.

Outside of the follicle we find the fibrous connective tissue
of the derma, built up by longitudinal and transverse bundles.
At the Ijottom of the hair follicle, in the human skin, a longitu-
dinal tract of fibrous connective tissue is often found, which runs
in the direction of the hair, and carries the blood-vessels (G.
Wertheim).

In comparing what I have said about the theory of the forma-
tion of the hair with specimens of the skin, a satisfactory con-
gruence will be found. This theory, as I have taught for nearly
seven years in my laboratory, Avill explain the fact that upon
pulling a hair the inner root-sheath is drawn out simultaneously
with the root. It furthermore explains the process of shedding
and the new formation of the hair.

(8) The Hair. As before mentioned, the part of the hair im-
planted in the skin is called the root, while the portion projecting
above the surface of the skin bears the name of shaft. Its main
mass is composed of delicate, flat, nucleated, fusiform epidermal
scales, which are fii*mly attached to each other, but may be
isolated by soaking in dilute acetic acid. The darker the com-
plexion of the indi^'idual, the greater is the amount of granular

570

THE SKIN.

pig'inent found both within and between the scales, which, in
addition, hold a diflfnse coloring matter, especially in red hair.
Gray and blonde haii* are without pigment granules. Alter being
pulled out the hair shows minute air-bubl)les in its substance ;
but there is no foundation whatever for the belief that the gray
color of the hair is due to the presence of such air-bubbles. The
original hue of the hair is caused by the pigment stored up in its
medullary and horny portion, and corresponds to the amount of
coloring matter present in the rete mucosnm of the skin, as
seen in leukopathia, vitiligo, and in variegated or pied animals.
Unquestionably, the amount of pigment is closely connected with

Fig. 237. — Pouch of the Hair from the Scalp of Man.
Traxsverse Section.

R. root of the hair ; C, cuticle ; IS, inner root-slieath ; .S'2, cuticular layer between the
two root-sheaths ; OS, outer root-sheath ; S^, hj'aline basement-layer between outer root-
sheath and follicle ; i^, follicle. Maguifietl 500 diameters.

the general nutrition of the skin and under the control of the
so-called trophic nerves, as proved by the rapid turning gray
of the hair in exhaustive diseases and after mental emotions.
The shape of the hair is best studied in transverse sections. Flat
hair exhibits, as a rule, a circular or oblong section, while in
curled hair this is elliptical or uniform. (See Fig. 237.)

Shedding of the Hair. We know through A. Kolliker and

77//'; SKfX.

I

C. Lander that tho youiij^- hair is foi'iuid aroiiiid th(^ old j)a|»illa.
We know, besides, that at a (rertaiii hei^lit above the i)a|)ilhi
tliei'f is a knob-like tliickeniiif^- (Ifeidc), which eorres})onds to
the hnlb of the falling hair. The faet adiled by uie is that tlie
new growth of a hair takes place exclusively within the inner
root-slie.itli. The inner root-sheath, below tlie bull* of the old
hair, wjiich is fringed by the torn epidermal seah's, be(*onies
gradually widened. At the bottom of the pouch it turns upon
itself and produces the bulb, which is composed of medullary,
or indifferent or embryonal, corpuscles. The }>oundary between
the two i)ortions of the inner root-sheath is established by the
cuticle, which, below the bulb of the old hair, is composed of

OH

-YR

Fig. 238.

•Diagram of the Process of Sheddixg of
THE Hair.

F, follicle ; M, arrector pili muscle ; P, papilla of hair ; B, bulb of hair ; IS, inner root-
sheath; O.S, outer ri)ot-8heatli ; C, cuticle; if, root; O/f, old liair still in connection with O'/O
the young hair rowing from the bulb.

columnar epithelia. The pigment, where there is any, lies
exclusively in the central portion of the inner root-sheath, from
which arises the future haii\ The outer root-sheath takes no
part in the new formation of the hair. The smooth muscles
of the follicle are evidently concerned in the process, inas-

572

THE SKIN.

much as through their contraction a narrow neck is estab-
lished around the young hair, as first suggested by Biesiadecki.
(See Fig. 238.)

The Df-velopmcnt of the Hair can be first traced at the end of
the thii'd month of intrauterine life. The epithelial investment
of the skin produces a knob-like prolongation downward, while
later an extension of the connective tissue is formed, which
lifts the bottom of the epithelial knob, and produces the papilla.
The epithelia are originally all medullary in character, and from
the medidlaiy corpuscles, by elongation and mutual flattening,

£, root of hair; 7.5, iimer root-sheath : O.S', outer root-slieath : G, sebaceous gland ; Z), duct
of the sebaceous gland : A, acarus foUiculoruni within the duct of the sebaceous gland.
Magnified 200 diameters.

arise the elements composing the hair in the center of the knob,
and also the root-sheaths at its peripheral portion.

(9) The Sebaceous Glands. The acinous sebaceous glands are
formed from the outer root-sheath of the hah-, and are usually
in close relation to the haii-. Sebaceous glands without hair
are found in the areole around the nipple of the female breast,
in the glans and the prepuce of the penis, in the nymph® and

THE SKIN.

573

tilt' pi't'jmcr of tilt' clitoris. In the palms of tli»' hands and the
soles of the feet tliere are no sebaceous glands.

The ndation of the j^lands to the hair varies gi-eatly accord-
ing to the size of the latter. The largest sehaceons glands are
found in the naso-la))ial folds ; here the fine lanugo hairs are
subordinate formations, piercing the duct at an acute; angle. At
the extensor surfaces of the extremities and the posterior aspect
of the trnnc the sel)aceous glands are elongated ; in the axilhv
they are Hattened. On the scalp they are sometimes small,
pear-shaped structures, and usually two of them empty into one
hair-pouch, both being under the control of the same fan-like
arrectorpili muscle (Hesse). (See Fig. 289.) Sometimes, however,
thev attain a considerable size. In horizontal sections of the

Fig. 240. — Scalp of Man. Horizontal Section.

H, root of hair, surrounded bj- its sheaths ; .S', sebaceous gland ; F, follicle common to the
hair-roots and the sebaceous glands. Magnified 200 diameters.

scalp we find groups composed of roots of hair and sebaceous
glands, inclosed by the fibrous connective tissue of the derma,
which sends delicate prolongations between the epithelial fonna-
tions. The numerous acini \'isible in this situation do not
correspond to single sebaceous glands, but to their branching
lower ends. (See Fig. 240.)

In specimens of sebaceous glands, preserved in a chromic
acid solution, the acini appear filled mth fat, and the lining

574 THE SKIN.

epithelia are not easily discernible. Treatment with alcohol and
tnrpentine brings the nucleated cuboidal e])ithelia distinctly to
view, and in such specimens we also recognize that the acinus
contains several layers of epithelia. In many sebaceous glands
a parasitic mite is found, the acarus or demodex folliculorum,
which is harmless, however.

(10) The sudoriparous glands are composed of a single coiled
tubide, lying in the deep parts of the skin, usually near or in
the subcutaneous tissue ; the same tubule produces not only the
coil, but the duct also, the difference being that the coiled portion
of the tubide is lined with cuboidal epithelia, and the duct, up
to the point where it reaches the rete mucosum, with the col-
umnar variety. If we assume a prolongation of the outer
epithelial layers into the depths of the derma, the formation of
the sweat-gland is easily understood.

The sudoriparous glands are present all over the skin, varying
in size in different individuals and in different localities; they
are most numerous in the palms of the hands and the soles of
the feet ; the largest are found in the axillge and in the neighbor-
hood of the anus ; they are not found in the glans penis and
the inner surface of the prepuce. They are all inserted in an
oblique direction in the derma, corresponding to the general
arrangement of the connective-tissue bundles. Their orifices on
the surface of the skin, in the furrows between the papillary
ledges, are perceptible to the naked eye. The sweat-glands at
the borders of the eyelids — the so-called glands of Moll — have,
it is maintained, spiral terminations, instead of coils, and empty
into the hair-pouch of the cilia. The ceruminal glands of the
external auditory canal are constructed like sudoriparous glands,
but secrete an unctions substance, which is commonly called
ear-wax.

By cutting through the coU, transverse, oblique, and longi-
tudinal sections of the tubule are produced. The lining epithe-
lium is, in this situation, a cuboidal or short columnar epithelium
in one layer, attached to a delicate hyaline membrane. In the
empty condition of the gland the caliber is very narrow, and the
cement-ledge of the epithelia is plainly marked at the surface
bounding the caliber. (See Fig. 241.)

The connective tissue carries a large number of capillaries,
and produces a capsule surrounding the coil, and prolongations
passing around the tubide through its whole extent. In the con-
nective tissue there are seen smooth muscle-fibers, which are very

77/ a; SKIX.

miiiRTous aroiiiitl the su(|i)ri|t<ii'(»iis «;l;iii(ls of llic iixillii', wli(;re
they form an almost (•oiitiniioiis layci-, which cxpaiKls into a flat,
sheet -like ai-raiiucmeiit.

Tlie diameter of the duet, at its l)e«;iiiiiiii,u', does not exceed
that of the tul)iile within the coil; very soon, however, it becomes
decidedly ])roader, and shows a sinj^le stratum of columnar epi-
tlielia (not stratified, as some authors claim) and a wide caliber.
These eonditi<ins are ])articularly marked in cross sections of the
duct, such as are often seen in the derma. Deli(;ate bundles of
connective tissue, arranged longitudinally, accompany the duct ;
no smooth muscle-fi})ers are present in them. The duct leads in
a slightly devious course to a depression between two papill*,
and in this situation is composed of stratified epithelia, a forma-

FiG. 241. — Coil ok the Sweat-gland.

8, tubule lined by cuboidal ppithelia ; T, ctutral caliber of the tubule ; JD, beginning of the
duct; C, connective tissue with injected blood-vessels. Mafrnitied 500 diameters.

tion of the rete mucosum, prolonged to a varying depth of the
duct. After having reached the epidermal layer, the duct is
lined by a single layer of flat epithelia, its caliber being consider-
ably widened, especially at its orifice at the surface of the skin.
Within the epidermal stratum the duct shows windings which
are scarcely perceptible in places where the epidermis is thin,
while in situations where the epidermis is very thick, such as
the palms of the hands and the soles of the feet, these spiral

576

THE HKIN.

windinj^s have the characteristic corkscrew-like appearance. (See
Fig. 242.)

(11) Tlw nails are flattened, ])hite-like formations of a horny
or epidermal character. The skin is elevated along the lateral
borders of the nail, and produces at the posterior end of the nail
a broad pouch, termed the matrix, which incloses the root of the
nail. According to Unna, the matrix proper of the nail is only
the posterior portion of the derma, commencing with the ante-
rior curved line of the lunula; and only the bottom of the fur-
row serves as a matrix to the anterior portion of the nail. H.
Hebra does not consider the lunula as a part of the matrix, for it
is destitute of papillae, and scantily supplied with blood-vessels

Fig. 242. — Duct of the Sweat-gland within the
Epithelial Layers op the Skin.

^P, papilla witli injected blood-vessels; I', valley between two papillii': .Z>, duct in the
rate mucosuni ; ^i', epidermal layer; PX, coarsely Kiaiiulated epitlielia, deeply stained with
carmine; P, duct with corkscrew windings in the epidermal layer. Magnified 200 diameters.

The papillary layer of the skin subjacent to the nail is
highly developed, the papiUae being arranged in parallel rows
corresponding to the long axes of the fingers and the toes.
The papilla? are shallow in the region of the matrix, but increase
in size toward the free portion of the nail, especially toward its
lateral borders. At the inner surface of the lateral ledges, and
in the depth of the lateral furrow, they are replaced by the pa-
pillae of the skin. The derma forming the papilla^ is composed
of coarse, dense bundles, inclosing a comparatively small number

77/ A" ,S7v'/.V. 7)17

of fat-i,4()l>iik's, and ])l('iidin<;- with the iK'riosteiiiii of tlic hist
pliahiiix. In this situation the vascular supply is strikingly-
large. (See Fig. 243.)

Fig. 243. — Nail op Finger, Vertical Section, Rectangular
TO the Long Axis of the Finger.

P, papilla' with blood-vessels ; B. rete mucosum ; A^ horny epidermal scales. Ma;?iiified
100 diameters.

The derma is covered by an epithelial layer, identical with
that of the rete mucosum, and filling the valleys between the
papillae in such a manner that the upper boundary of the rete
mucosum exhibits only a fluted contour. According to C. Toldt,
the so-called lunula of the nail, most distinctly marked on the
nail of the thumb, is caused by a lessened transparency of the
nail, due to the rete mucosum producing, in this situation, a
broad layer of a uniform distribution. The rows of the papillae
are much less developed in the region of the lunula than in the
rest of the matrix. By scraping with the knife the low^er surface
of the detached nail, the lunula disappears, and the nail becomes
uniformly transparent.

The nail substance consists of horny epithelia, of which the
lower ones exhibit indistinct nuclei, while the outermost resem-
ble epidermal scales. In the region of the root a gradual tran-

578

THE SKIN.

sition from the epitlielia of the rete mucosinn into the horny
epithelia takes place.

In the hiteral portions of the nail, where papilla? are ab-
sent, the rete mucosnin of the skin, forming- the ledge and the
fnrrow, passes into that of the nail throngh irregular, branch-
ing prolongations, which exhibit marked layers of epithelia, more
or less endowed with life. In this situation the papillas of the
nail are lost, but are replaced by very small and elongated
papillae, which belong to the skin and stand in an oblique direc-
tion to the rows of the papillae of the nail. A true transverse
section through the nail will exhibit within the furrow oblique
and transverse sections of the slender papilla? of the skin. (See
Fig. 244.

rr'J^r

Fig. 244. — Implantation of the Nail at its Border.

P, papUlffi, decreasing in size toward the middle line ; li, rete mucosnni, which broadens
toward the border of tlie nail, and forms irregular prolongations, -R' ,- E, epidermal laj'er of
middling consistence ; N, plate of the nail. Magnified 50 diameters.

The epidermis of the skin produces a pointed prolongation,
which overlaps the borders of the nail ; this prolongation is most
clearly marked along the posterior border.

(12) Tlw lactcdl glands are accessory formations of the skin.
According to C. Langer, who has made careful researches on the
development, the structure, and involution of the lacteal glands,
they begin to form in the third month of embryonal life, and in
the fifth month present radiating tubules, with club-like termina-
tions. The tubules open into a shallow depression of the skin, the

77//'; .s'A7A'.

r)79

or

— CE

nipple Itt'iiii^- alisciit. In tin- nrw-ltoi'ii infant the tnluilcs hi'ancii
several times, and all of tluMn show clavate termination. The
ramifications increase in nnni]»cr, in both sexes, n]) to the twelfth
year, without the production of acini, the nniin mass consisting'
of connective tissue, destitute of fat-^'h)l)ul('s.

At the time of pul)erty in j^-irls the mammary }i,ian(l deveh>ps
into a discoid body, composed of dense, fibrous connective tissue,

witliout fat; tlie i-adiat-

iugranmlesexliibit in this
period acinous termina-
tions at tlie peri})heiy of
the organ, and only here
is the lobular structure
marked.

In pregnancy a con-
siderable development of
the acinous glands takes
place, especially toward
the end, Avhen al)out
twenty ducts are found,
emptying" at the point of
the nipple, and a corre-
sponding number of lob-
ules is produced by the
free ramification of the
ducts and the formation
of numerous acini within
one lobule. The duct.s, before emptying, are widened into pear-
shaped sinuses ; their lining throughout the ramification consists
of a single layer of columnar epithelium. The acini are lined
with cuboidal epithelia, and at the beginning of lactation exhibit
numerous fat-granules, both within the epithelia and the caliber.
(See Fig. 245.)

In full lactation the lobules and the acini therein assume the
largest size ; the epithelia are scarcely perceptible, for most of
them are transformed into fat, and upon being treated with tur-
pentine usually show the frame of cement-substance, the nuclei,
and numerous vacuoles (see page 332). After the period of
lactation has passed, the acinous structure of the gland re-
mains, the small acini surround the ducts in regular gi'oups, and
the connective tissue now contains a large number of fat-glob-
ules. In the matron a few ducts only are found, lined with

Fig. 245. — Acini of the Female Breast
AT THE Beginning op Lactation.

CE, cuboidal epithelia; F, fat-globules, both witliiu
the epithelia aud the caliber, stained black by osiuic
acid ; CV, couuective-tissue frame, with blood-vessels.
MaKuified GOO diameters.

580 THE SKIN.

columnar epithelia, partly filled with minute fat-granules ; acini
are wanting.

In male adults the mammary gland exhibits a structure simi-
lar to that of the new-born infant ; real acini do not exist, even
though the gland may attain a considerable size.

The lowest layers of the rete mucosum of the nipple and its
areole contain pigment granules ; the papilhe are very large and
branching, and have either capillary loops or tactile corpuscles.
The derma is freely supplied with bundles of smooth muscle-
fibers in a reticular arrangement; they are twined around the
lacteal ducts in a vertical direction.

Within the areole the connective tissue of the derma and the
subcutaneous layer is free from fat. During the latter months
of pregnancy small granular elevations are found in the areole,
which are sebaceous glands, emptying at the height of the
granule. They have been erroneously described as accessory-
cutaneous lacteal glands. Occasionally they give rise to an
active glandular new formation, with the production of a
sebaceous adenoma.

Inflammation of the Skin.* I have studied the process of inflammation of
the skin in specimens from a syphilitic papule ; from small-pox ; fi'om an
ulcerating sac of umbilical rupture in a cat. I have investigated the termina-
tions of inflammation in specimens of elephantiasis of the scrotum and of the
labia majora. Inflammation as an accompanying process I have studied in
the skin of the female breast in mastitis and cancer, and also in the skin
covering different benign and malignant tumors, or directly involved in
the formation of such tumors. The results in all these cases being almost
identical in regai'd to the essential changes in the tissues of the skin, I can
confine myself to tlie description of the inflammatory process in small-pox,
of which I obtained six different specimens from the Blackwell's Island Hos-
pital ; among these were two of htemorrhagic small-pox.

The coarser microscopical featiu'es in the formation of small-pox have been
accurately studied by Auspitz and Baseh. The essential structural changes
observable with high magnifying powers of the microscope, — 800-1200
diameters, — and which can be understood only upon the knowledge of the
normal anatomy of the affected tissues, are as follows :

First, the epithelial layer, termed rete mucosum, appears slightly thick-
ened in eii'cumscribed spots ; the swelling is due to a coarse gi-anulation of
the epithelia themselves. This granulation is produced by an increase of
living matter within the epithelia, evidently through an augmented afflux of
nourishing material dm'ingthe stage of hyperaemia. The points of intersection
of the net-work of living matter, the so-called gi-anules, become enlarged,
many of the nuclei are solid and shining, and at the same time the threads

>•" Microscopical studies on lufiaiumation of tlu^ Skin." A paper read before the Ameri-
can Dermatological Association at their meeting in New- York, August 27, 1879. Publisheil
in abstract in The Chicago Medical Journal and Examiner, October, 1879.

THE SKJX. 581

traversing the eenieiit-substanee, the formerly so-culled "thorns," become
thickened. The nnderlying iJiipilliw are slifjhtly enlarf^ed in all diameters,
partly owiiifj to a dilatation and eiif^orpement of their capillary blood-vessels,
partly thronj^h a peculiar change of the V)undles of the connective tissue and
the bioplasson bodies between them. The latter look slightly enlarged, and
in many instances coarsely granular; the former are partly transformed into
bioplasson. In other words, where before bundles built up by a glue-yielding
basis-substance were i)resent, the reticulum of the living matter, before hidden
in the relatively solid basis-substance, becomes visible again tlirough a lique-
faction or dissolution of this substance. No other proof of the presence of
an exudation in this stage can be obtained, except the liquefaction of the
basis-substance. 77//.s' stai/c of injlaximation is termed " jxipular."

Next, in the middle of the papule, on one or on several spots, the exuda-
tion makes its appearance ; the outer or epidermal layer at no time partici-
pates in the morbid process. In some epithelia we notice an enlargement of
the meshes of the living reticulum; the latter is first stretched, afterward torn
apart, the granules being suspended in the liquid exudation. Where epithelia
were present before, a small, irregular cavity is visible. K several such
cavities have formed in a papule through a continuously increased accumula-
tion of the exudation and destruction of the epithelia, the separating layers
of the epithelia become compressed and produce septa, traversing the cavaties.
Such septa vary greatly both in number and width. The neighboring epithelia
have a coarsely granular appearance. Many of them have lost the inclosing
cement-substance, and are thus transformed into clusters, in which, through
a considerable increase of the living matter, new shining lumps of different
size appear, which are still in continuity -with the neighboring reticulum
by means of delicate threads — the so-called endogenous formation of new
elements. The result of this process is the formation of an irregidar cavity
in the middle of the greatly widened rete mucosum, traversed by septa of
compressed epithelia, and filled with an exudation, in which there are sus-
pended numerous delicate gi-anules, generally termed coagulated albumen,
and a varying amount of irregular threads in the form of a felt-work, the
coagulated fibrine. A few scanty plastids are also suspended in the exu-
dation, perhaps remnants of the destroyed epithelia, perhaps immigrated
iniiammatory or colorless blood-corpuscles.

In this condition of the rete mucosum, the underlying connective tissue
exhibits considerable changes. The papillae have disappeared, CAadently
through the pressure from above. The transformation of the connective
tissue into bioplasson has advanced, in some instances, to such a degree that
the uppermost layers of the derma are replaced by numerous indifferent, or
medullary, or inflammatory corpuscles, as a rule, clustered together. All
these elements, however, are in an uninterrupted connection with each other
through delicate filaments of liA-ing matter, fully analogous to those of the
epithelia, and thus the inflamed tissue, though reduced into its mediUlary con-
dition, still represents a tissue. The stage of the disease in which the changes
just described had taken place is known as the vesicular steuje of smnll-pox.

Lastly, pus-corpuscles appear in the ca\'ity within the rete mucosum.
The main mass of these doubtless arise from the epithelia traversing and
bouniiing the cavity. Through the increase of living matter in the large num-
ber of epithelia, shining lumps appear, first homogeneous-looking, afterward
tlirough the intermediate stage of vacuolation transformed into nucleated plas-

582 THE SKIN.

tids, with a fully developed reticulum of living matter — the pus-eorpuseles.
The principal sources of pus-corpuscles, therefore, are the epithelia themselves,
the endogenous formation. (See page 419, tig. 176.) How many of the
pus-coi-puscles appear through an immigration from below, from the inflamed
connective tissue or from the blood-vessels, nol)ody can tell. The immigra-
tion is a sensible hypothesis only, without direct proof or foundation, while
the endogenous formation can be directly traced in all its stages. The jjus-
corpuscles are coarsely gi-anular, viz. : are supplied with a large amount of
living matter at the points of intersection of the living reticulum in persons
of a good, strong constitution; on the contrary, they are finely gi-anular — that
is, scantily provided with living matter — in persons of a weak, so-called scrofu-
lous or tuberculous, constitution, or in persons debilitated by any acute or
chronic disease. In the former instance the pus is thick and yellow, in the
latter instance watery, serous, and pale. The subjacent connective tissue, as
a rule, does not advance beyond its reduction into a medullary tissue. In
some eases, however, the newly appeared and newly formed medullary cor-
puscles, which produce the infiltration of the derma to a varying depth, are
also torn asunder, and thus represent pus-corpuscles, which, commingling with
the pus which has sprung from the epithelia, take part in the formation of the
abscess.

This stage of infiammation is known by the term jinstular stage of small-pox,
and represents the typical termination of the whole i)rocess. The pustule
either bursts or its contents dry and produce the crust. So long as the
inflamed derma remains in the condition of medullary tissue, so long as
the medullary or inflammatory elements remain connected with each other,
the new formation of a glue-yielding basis-substance in the shape of bundles
of fibrous connective tissue will be accomplished, withoiit the formation of a
scar. If, on the contrary, a part .of the connective tissue has been trans-
formed into pus, and thus completely destroyed, the result will be a cicatrix.
Mere epithelial suppuration heals without the formation of a scar, while sup-
puration of the connective tissue always produces a mark. The pigmentation
of the skin, so common after small-pox, is due to the imbibition of the color-
ing matter of the red blood-corpuscles ; or by changes of the directly extrava-
sated red blood-corpuscles, both in the rete mucosum and the derma. Such
extravasations occur in all severe cases of small-pox — in the highest degree,
of course, in hsemorrhagic small-pox.

My observations on inflamed jjortions of skin have led me to the following
conclusions :

(1) In epithelium, the first step of the inflammatory process consists in an
increase of the living matter, both in the plastids and between them; the
former produces the coarse granulation of the epithelia, the latter the thick-
ening of the so-called "thorns" in the cement-substance. Any particle of
living matter, both in the epithelia and between them, through a continuous
growth, may lead to a new formation of the epithelial elements, with termina-
tion in hyperplasia of epithelium (psoriasis, squamous eczema, horny forma-
tions, etc.).

(2) In connective tissue, the first manifestation of the inflammatory
process is the dissolution of the basis-substance and re-appearance of the
bioplasson condition ; by this process and the new formation of medullary
elements, which may start from any particle of living matter, the inflamma-
tory infiltration is established. The sum total of the inflammatory corpuscles.

THE SKIX. 583

which roiuaiii united with each other by means of delicate offshoots, represents
an embryonal or jnedullary tissue. If the new formation of medullary cor-
jmscles be scanty, resolution is accomplished by new formation of the basis-
sul)stance (erj-thema, erysipelas, etc.)- If. on the contrary, the new formation
of medullary elements l)e profuse, a new formation of ci>iinective tissue will
result ^hyperplasia, sderodenna, ele])hantiasis. etc.).

(;}) Plastic (formative) intiainmation may be accompanied by the accu-
mulation of a larger amount of a serous or albuminous exudation in the
epithelial layer (miliaria, sudamina, herpes), or in the connective tissue of
the derma (urticaria). In both instances complete resolution will ensue.

(4) Suppuration in the epithelial layer of the rete mucosum is produced
by an accumiilation of an albuminous or fibrinous exudation, by which a
numlier of epithelia ai'e destroyed, and by new fonnation of pns-corpuseles
from the livinj; matter of the epithelia themselves. Epithelial suppuration
heals without the formation of a cicatrix (eczema madidans et pustulosum,
impetigo, pemphigus, variola).

(5) Suppuration in the connective tissue of the derma results from the
breaking apart of the newly formed meduUarj' corpuscles, which, being sus-
pended in an albuminous or fibrinous exiidation, now represent pus-corpus-
cles. Pus is a product of the inflamed connective tissue itself, and is always
a result of a destruction of this tissue. Suppuiation of the derma invariably
heals through cicatrization (abscess, furuncle, acne, ecthvTna, variola).

Tumors of the Ski)).* (1) Myxo)))atous or m))ico)(J tumors are composed of a
delicate fibrous reticulum, the meshes of which contain a jelly-like basis-
substance and plastids var^^ng greatly in size. They are frequently found
on the skin as soft, jelly-like, sessile, or pediculated protrusions. They are
often supplied w^th a large quantity of blood-vessels, and are then soft
tumors, of a dark red color, the •' mj'xo-angioma." Myxomatous tumors,
having the structure of the thjToid body and called " hnuph-adenoma " or
"lymphoma,'' are very rare. They may occur iu the subcutaneous tissue
of the neck, but have no connection with the th>Toid body itself.

(2) F)b)-ous t)()))0):s in all their varieties (see page 483), and also the com-
bination of fibrous with mj-xomatous connective tissue, so called "myxo-
fibroma,"' being, as a rule, scantily supplied with blood-vessels, are common
tumors of the skin, appearing as hard, sessile nodules and nodes (hfi)-d
fibroma), or as pedunculated tumors, sometimes scattered over the entire
tegumentary svu"face (fih)-o)na ))iolluscu)))) ; as tumors of varj'ing size, and
softer consistence (soft or )nyxo-fib)-o)iia) ; as pigmented flat elevations of the
skin ()ta'vi) ; or as scar-like, iiTegularly branching, sometimes freely vas-
cularized new formation (keloid). The peculiarity of these entirely benign
tumors is that after extii'pation they sometimes recur, and even the scar,
after the removal of a fibroma, may assume the features of a keloid.

(3) Choudroma and (4) Ost('0)»a, do not occur on the skin.

(5) M)jelo)))n (sarcoma), in its two principal varieties — viz. : globo-mye-
loma and spindle-myeloma — is of somewhat infrequent occurrence; in the
derma it usually appears as fib)o-))))/ek»))a ; rarely as a pigmented )ue1a)iotic
jnyeloiua. Such tumors originate as nodules of the skin, sometimes accom-
panied with inflammatory symptoms, and their malignancy is proved by their

* A paper read before the American Derniatological Association, at tlieir meeting in New-
port, R. I., Aupiist 31, 1880. Printed in abstract in " Archives of DermatoloK.v," Philadel-
phia, October. 1880.

584 THE SKIN.

rapid growth, by a new formation of nodules in the vicinity of the primary
tumor, and by their recurrence after extirpation. An original myxo-fibronia,
after repeated extirpation, may gradually assume the features of fibro-mye-
loma. The vascular supi)ly of myeloma is sometimes scanty, at other times
abundant. Some of these tumors multii)ly rapidly all over the skin, especially
in the subcutaneous tissue, and some may, after reaching a certain size, dis-
appear, while new nodules may form in other localities. The melanotic vari-
ety usually starts in the skin of the hands and the feet, and in a comparatively
short time invades large portions of the surface of the body, and never admits
of a cure. After extirpation, many of these tumors recur with great
obstinacy, in the scar or in its vicinity, and prove more malignant with each
re-appearance, until at last an operation becomes impossible. The patient
dies, with symptoms of inanition, from the exhausting waste of living matter
within the rapidly growing tumor, or from secondary formations in internal
organs.

(()) Lipoma is a common type of tumor, occurring in the subcutaneous tis-
sue, evincing some predilection for the posterior aspect of the body, and
sometimes appearing as a diii'use accumulation of fat-tissue in the female
breast. Lipoma combines with myxoma or myxo-fibroma, constituting the
variety called "cutis pendula," or " leontiasis," which sometimes attains
enormous size.

(7) Angioma, in its three varieties, is found in the skin. Simple and lob-
ular angioma is usually seated in the derma, while the cavernous angioma,
which is rarer, generally starts in the subcutaneous tissue. These tumors are
all easily compressed, the blood disappearing, but returning when the pres-
sure is removed. The dark red or bluish-red color is, as a nile, a marked
feature, though wanting in the deeply situated cavernous tumors. New for-
mations of lymph-vessels — the so-called li/Diph-aiif/ioiita — oceiu- in the tissue
of tlie derma ; the cavernous li/iiiph-a>i(jioiua is a rare formation in the subcuta-
neous tissue.

(8) Myoma has been observed by Virchow and others, usually occurring as
small, flat, erectile tumors, in the skin around the nipple and in the scrotum.
No ease has as yet come under my observation.

(9) Ni-uromata appear in the skin as nodules, not attaining a large size,
but characterized by their excessive painfulness. Tlie great majority of tliese
tumors are fibrous in structure, starting from the perineurium, and seiiarating
the medullated nerves.

(10) PapUlonia is often found on the hands as simple irarts ; on the geni-
tals as condylomata, and in other localities, though rarely, as hairy and warty
moles (nsevus verrucosus). The latter variety is congenital, while all other
warty tumors are acquired, being due to some local irritation. I have seen
the so-called venereal warts, on the skin of the back, evidently produced by
transmission of the blennorrhagic secretion ; on the chin — conveyed proba-
bly by the barber — and on the forehead and eyelids of a child — infected by
the nurse. A peculiar feature of these tumors is that they are difficult to
eradicate. Sometimes, in advanced age, they change their nature and become
cancerous, especially in the face.

(11) Adenoma appears almost exclusively in the skin as adenoma of the
sebaceous glands. Adenoma of the sudoriparous glands has been described
by Verneuil only, and its existence is very doubtful. A variety of acinous
adenoma, starting from the lacteal glands, is very common in the appendage

THE SKIN. r)85

of tlio skill, tlio fi'iniilc l>r(>iist. In tiiinors svliidi iiri' eitlier sessile or pedieu-
latetl — moll use II in srbmTum — the rtit'einose sebaceous f^laiids are sometimes
enormously auf^ineiited, while the interposed fibrous conm'etive tissue is con-
siderably diminished. The epithelium sometimes undergoes a colloid or waxy
degeneration, producing large, shining, homogeneous, even stratified bodies,
which were thought to be characteristic of itioUiisviuii ciintai/iosinti.

Ci/stic timioYs are secondary formations of adenoma ; they are filled with a
serous liquid (serous ci/st), with a viscid, colloid, honey-like liquid (meliccris),
with a soft, fatty, offensive paste (sebaceous cyst), or with a half-dry, viscid,
slightly rancid mass (derniohl cyst). It is very doubtful whether simple
obstruction of a duct of a gland will ever give rise to the formation of a cyst,
unless previous new formation of epithelium be present, the secondary
changes of which give the characteristic properties to the contents of a cyst.
Sebaceous cysts, so-called wens, are of frequent occurrence, most commonly in
the skin of the scalp and of the face ; they are sometimes present in a very
large number. The sebaceous matter is inspissated and infiltrated vnth lime-
salts in cysts termed luilium.

(12) Carcinoma, in all its varieties, — Hat, nodular, ])apillary, and plexiform
epithelioma, scirrhus, and medullary cancer, — is observed in the skin. It is
obvious that terms like "alveolar cancer," " epithelial cancer," "plexiform
cancer," "epithelioma," etc., are misnomers, as every cancer is necessarily
alveolar, and is an epithelioma. We have no reason to confine the name
" epithelioma" to cancers of the skin, as in this tissue all varieties occur.

Flat cancer (so-called "rodent ulcer") is usually seen in the skin of the
face, never producing exuberant growths ; but by continuous ulceration it
penetrates into the deeper parts and gradually destroys all the tissues. It is
the least malignant form of carcinoma, and never produces secondary tumors.
Nodular cancer (so-called "epithelioma") is of frequent occurrence in the
skin, usually starting in localities which have been the seat of a long-con-
tinued though slight irritation. Papillary cancer (so-called cauliflower
cancer) is rare, and appears whenever an exuberant growth of circumscribed
portions of the tumor takes place toward the sui'face. Scirrhus and inedidlary
carcinoma may grow on any part of the siu-face of the body, more particu-
larly in the female breast. Melanotic carcinoma is rare. In very rapitUy
gi'owing carcinoma epithelia do not develop, and the tumor remaining in the
stage of the so-called medullary or inflammatory infiltration exhil)its the feat-
ures of globo-myeloma. This is especially marked in the rapidly growing
so-called lenticular cancer (cancer a cuirasse) of the skin.

XV.

THE DIGESTIVE TEACT.

THE digestive tract is a coutiuuous canal extending from
the mouth to the anus, widening into the cavities of the
mouth, the pharynx, and the stomach. Its walls are composed
of connective tissue, and either striated or smooth muscle-fibers,
and lined with epithelium, which is partly stratified and partly
arranged in a single layer. The beginning and termination of
the digestive tract are under the control of voluntary striped
muscles. The flat muscle-layers keep the canal closed, unless
solid, liquid, or gaseous material separates its walls and tem-
porarily makes the caliber patent. All portions of the canal are
in a high degi'ee extensible.

The characteristic feature of the mucous membrane covering
the whole length of the tract are stratified epithelium in the
walls of the mouth, the phar^Tix, the oesophagus, and the lowest
portion of the rectum ; flat epithelium in the wall of the stomach,
and a single columnar epithelium throughout the intestines.
Delicate fibrous, and partly mj^omatous, connective tissue,
freely supplied with blood- and l\^nph-vessels, is found in the
walls of the oral cavity, forming papillte, which reach their
highest development in the mucosa of the tongue ; and are also
present in that of the pharynx and oesophagus. Connective
tissue also produces the filiform elevations in the small intestine
and the projections and folds in the large intestine ; besides all
folds occluding the caliber of the canal when in an empty con-
dition. The connective tissue surrounds the epithelial prolonga-

77/ 7-; DKIKSTIVK TRACT.

587

tions — /. c, acinous mucous pflands in tlic crtvitv of the mouth,
the throat, the (esophaj^us, in the lowest portion of the rectum,
and in the walls of the duodenum. It also holds the tubular
pepsine-j?lands of the stomach and the tu))idar intestinal j^lauds
in the small and largfe intestine. The connective tissue forms,
especially in youth, a layer of ]ym{)h-corpusclcs, the so-called
'' adenoitl layer" of myxomatous structure, which is permanent
in the villosities of the small intestine, and accumulates here in
the solitary follicles and the follicular ])atches. The mucosa, in
many portions, has a circular and longitudinal layer of smooth
muscles of its own ; wliilc the canal is everywhere surrounded

Fig. 246. — Lip of a Child. Vertical Section.

^, epidermis ;£, rete niucosuiu : i*/", impIlliB ; 7>, tlerma, with injected blood-vessels .V.
striped muscle-fibers. Magnified 200 diameters.

by a circular and longitudinal layer of striated or smooth muscle-
fibers, with additional oblique layers in the oesophagus and
stomach. The loose fibrous connective tissue, which unites the
mucosa to the muscle, is termed the suhmucous hii/fr. and con-
tains, besides a varving amount of lymph-coi'puscles, larger
blood- and lymph-vessels and numerous nerves in plexiform
arrangement, holding scattered or grouped ganglionic elements.

588

THE DIGESTIVE TRACT.

In the abdominal cavity, the outermost hiyer of the digestive
tract is formed of connective tissue and lined with endothelia —
the peritoneum.

The salivary glands, pancreas, and liver — glandular forma-
tions which aid in the digestive process — are situated along the
tract, and empty their secretions into its cavities.

(1) The Oral Cavity. The lips are composed of a dense, inter-
lacing fibrous connective tissue, of which the lower portions are
connected with numerous striped muscles, and the upper por-
tions produce the papillee, sometimes showing bifurcating apices,

CF

Fig. 247. — Papilla from the Lip of a Child.

CE, columnar einthelium, nearest to the connective tissue ; CF, connective tissue, crowded
■with plastids ; ^, arteriole; (.'!', capillary loops ; I', vein. Maffniiied 600 diameters.

and arranged in alternating large and small ones. (See Fig.
246.) The capillary reticulum of the large papillae is very dense,
and can be traced in direct connection with arterioles and veins.
The vermilion color of the lips is due to the large number of
capillaries. Within the papillaB the connective tissiie is com-
posed of delicate fibers, with comparatively numerous plastids,
which usually have the size and appearance of nuclei. (See
Fig. 247.)

////•; 1)1(1 EST ivE riiAcr. 589

Tilt' cpitlirliuin is (•(tntiiiiKnis with that of the skin, and is
stratitti'd; the surface of the lii)s, liowever, appears smooth,
because tlu' epithelial cover does not follow t\\v. curves of the
papillary elevations. The sanu' peculiarity is found all over the
oral mucosa. The epithelium sends prohmgations into the con-
nective tissue forminji: the racemt)se mucous glands, which, on
the inner surfaces of the lips, are very large, and visil)le to the
naked eye. Similar formations are found in the whole mucosa
of the oral cavity.

The mucosa of the or<d cuviti} is thickest on the hard palate,
especially its posterior portion, and intimately connected with
the sul)jacent periosteum. Very coarse bundles of fil)rous con-
nective tissue, blending- with the periosteum, compose the gums,
on which large papillii? are also found. In the floor of the oral
cavity the connective tissue is comparatively loose, and the strat-
ified epithelial layer thin ; here and on the reduplications of the
mucosa (frenulum linguiP, arcus glosso-palatinus, etc.) the pap-
illae are imperfectly developed. In the epithelial layer of the
soft palate and palatine arches bud-like formations are found,
similar to those of the circumvallate papillae of the tongue.
Many papillae contain terminal nerve-buds (Krause's bulbs), con-
nected with medullated nerve-fibers. Such structures are found
in larger numbers on the inner sui-face of the lips, and on the
anterior surface of the soft palate.

(2) TliP tongue is a bulky mass of striped muscles. Its cover-
ing mucosa is smooth on the lower surface, while the upper is
abundantly provided with numerous large papillae, and in this
situation the stratified epithelial investment follows the papillary
curves. Three varieties of papillae are found on the tongue —
viz. : filiform, fungiform, and circumvallate.

(a) The filiform papilUe, the most abundant, occui* over the
entire upper and anterior surface of the tongue ; they are long
and slender (1-2 mm. in length), and composed of connective
tissue, dividing at tlie apex into a varying number of thread-like
offshoots. They are largest in the middle of the upper surface
of the tongue, especially toward the location of the circumvallate
papilla?, while at the point and the lateral borders of the tongue
they become smaller. In children they are comparatively much
less developed than in adults. The stratified covering epithelium
produces hair-like elongations, which are composed of flat, horny
epithelial bodies corresponding to the projections of the connect-
ive tissue ; such projections are wanting in children and on the

590

THE DIGESTIVE TRACT.

filiform papill* of the lateral border. Terminal nerve-bulbs
have been found at the bases of these, papillae. (See Figs. 248
and 249.)

(hj The f Kit (J if arm papilla' are semi-giobular or oblong forma-
tions scattered between the filiform papilla? (usually not exceed-
ing one mm. in breadth and height), and arising from the level of
the mucosa with a slightly narrowed neck. Toward their cir-
cumference the connective tissue produces a number of smaller
so-called secondary papillae, which are not marked on the outer
surface of the thin epithelial investment. Sometimes the body of
the papilla is cylindrical, without a neck, and the epithelium may
assume featm-es reseml)ling those of the filiform papillae, though

Fig. 248. — Filiform Papillae of
THE Tongue op Max.

E, layer of liorny epitlielia ; C, connect-
ive tissue witli injected blood-vessels ; L,
ISTuphatic (adenoid) layer ; M, strliied mus-
cles. Magnified 150 diameters.

Fig. 249. — Fungiform Papil-
la OF THE Tongue of Man.

E, epitlielial layer ; C, connective
tissue with injected blood-vessels; L,
IjTnpliatic (adenoid) layer ; J/, striped
muscles. Magnified 150 diameters.

the prolongations are never numerous, and usually short and
broad. Such papillae are described as conical. Terminal nerve-
bulbs are found at the bases of the secondary papilli».

(cj The circumvallate papillce., situated at the posterior part of
the upper surface of the tongue, represent cylindrical elevations
(1-2 mm. in height and 1-3 mm. in width), Avhicli are surrounded
by a wall of the mucosa, and separated from this wall by a fur-

I 111-: I>l(ii:sTIVK TRACT.

591

row. The funow may divnde the central papilla into two parts,
or be very shallow. The secondary papilla* are present on the
upper surface of the central jiaiiilla" only. The smooth epithelial
investment in the lateral })ortions of the i)ai)illa, and also of its
suiToundinjjf wall, contains ])eculiar bud-like f<»rmations(Schwalbe,
Loven) — the gusfdtori/ buds. (See Fi^. 'JoO.) The.se are com-
posed, at their periphery, of large, iml>ricated, so-called covering
epithelia, while in the center of the bud delicate spindle-shaped,
so-called gustatory, epithelia are inclosed. Their connection with
non-medullated nerve-fibers has not as yet been conclusively
proved. The apex of the gustatory bud is marked by a shallow
depression. The ledges along the lateral borders of the tongue
are called papilUe foUatoe, and are composed of a number of coal-

FlG. 250.— ClKCUMTALLATE PaPILLA OF THE TOKGUE OF ^MaX.

£, epithelial layer ; G, gustatory bud ; C, connective tissue with injected blood-vessels ; M,
macoos glaiid with dact. Hagniiied 150 diameters.

esced papillary formations of the mucosa, with interspersed
fungiform papillae. In these ledges, which in man are not con-
stant formations, gustatory buds have also been found.

The ghnidular prolongations of the epithelium, covering the
tongue, are simple acinous and racemose mucous glands, similar
to those of the mucosa of the oral cavity in general. They are
large in the neighborhood of the circum vallate papilla?, and ramify
between the superficial muscle-bundles ; some of them empty in

592 THE LIGE STIVE TRACT.

the furrow of the cireumvallate papillae. On the anterior portion
of the ton^ie mucous glands are found only along the lateral
border, which coalesce into a larger group at the apex of the
tongue.

At the posterior portion of the mucosa of the tongue, where
papillae are not present, a varsing number of nodular elevations
occur, which are lymph-ganglia, and have been erroneously
termed " follicular glands." They are accumulations of hTuph-
tissue with numerous follicular formations, and in their centers
usually show a longitudinal cleft, in open cf)mmunication
with the outer surface of the tongue. Stratified epithelium
directly covers the hTnph-ganglion, the papillae being imperfectly
developed on the outer periphery' of the ganglion and altogether
wanting within the cleft. Sometimes the fibrous connective
tissue produces a distinct capsule around the ganglion. Dif-
fused layers of lymph-tissue immediately above the muscle of the
tongue are also obser%-ed, especially in children.

The muscle-fibers of the tongue are of the striped variety;
they interlace in different directions and produce a dense felt-
work, are attached to the fibrous septum in the longitudinal
median line of the tongue, and freely ramify upon approaching
the mucous layer, Avith which they blend. The perimysium con-
tains a varying number of fat-globides, chiefly in the posterior
portions of the tongue.

The blood- and lymph-vessels are numerous. The latter,
according to Teichmann, produce two plexiform extensions, the
upper and finer of which lies close beneath the papillae, receiving
the usually single lymph-ramules from the filiform papillae and
the plexuses from the fungiform and cireumvallate papillge. Rich
plexuses of hTnphatics surround the hanph-ganglia.

(3) In the pharynx and cesojyhagns the structure of the mucosa
resembles that of the oral cavity — i. e., it has small papilla, not
distinctly marked on the epithelial surface. The latter is strati-
fied and produces small acinous mucous glands, which are more
numerous in the throat than in the oesophagus. In the lower half
of the oesophagus they are absent, except in the portion immedi-
ately above the cardiac orifice of the stomach (Kolliker). The
stratified epithelial investment in the neighborhood of the choanae
blends ^vith the ciliated columnar epithelia of the nasal cavities.

The lymph-tissue is a widely spread formation in the mucosa
of the phar^'nx ; besides, a large amount is stored up in the
two lymph-ganglia, the tonsils, which are situated in the niches

rill': niGESTivK thact. :m

bt'twci'U till' ^i()ss()-j);il;it(.'al ami pharyn^o-palatcul folds. The
tonsils vary {greatly in size ; sometimes the lymi)h-follicles which
l)uil(l tht'iu up are scanty, at other times iinmerous. Fi-om tin;
covering mucosa a numl)er of depi-cssious are formed, simihir
to those of the lymph-follicles on tlic l»ase of the tongue. These
de])ressions in the tonsil may have several lateral cloii^-ations
unitin«>- with a central cleft, the so-called crypts of the tonsil. In
the cavities a viscid, cheesy mass is often formed, which is not
infrequently the seat of a calcareous deposition. The mass
proves njxrn examination to be composed of leptothrix (E. Griin-
inji'), a f uufj^ns which is a normal occurrence in all fuiTows of the
oral cavity, especially those between the gums and the teeth. In
the mucosa covering the tonsils, acinous mucous glands are
present. H^i3er})lastic tonsils do not histologically differ from
normal lymph-ganglia, with numerous follicles.

In various situations in the wall of the pharynx lymph- tissue
is found, and on the roof the aggregation of this tissue bears the
superfluous name of the pharyngeal tonsil.

The a'sophagus in rest appears completely closed by large folds
of the mucosa, which is composed of a loose fibrous connective
tissue, and admits of a high degree of extension. Along the
epithelial cover it shows numerous small papilla?, but which are
not marked on the surface of the stratified epithelium. The vas-
cular supply is very abundant in the layers, directly below the
epithelium, but scanty in the portion near the muscle. The
muscle in the upper half or two-thirds of the oesophagus is of the
striated variety, composed of at least two layers, an outer longi-
tudinal and an inner circular, and in some places near the mucosa
a second longitudinal or oblicpie layer is often found. In the
oesophagus of the rabbit this is a constant formation. (See Fig.
251.) In the lower portions of the oesophagus a gradual transition
of the striated into smooth muscle-fibers takes place. In the pos-
terior wall, according to Treitz, the striped muscles extend down
more deeply than in the anterior, and bundles of these muscles
terminate in tendinous formations, which blend with the external
fibrous investment. The mucosa of the oesophagus has also
independent bundles of smooth muscle-fibers, which are scanty in
its upper portions, but form a continuous layer in the thoracic
portion (Toldt).

(4) The Htonuich. The mucous layer of the stomach is marked
by an abundant glandular apparatus, the so-called gastric tiihules
or pepsine glands. This mucosa, owing to its attachment to the
38

594

THE DIGESTIVE TRACT.

muscle-layers, is capalile of producing- very large folds, which
are arranged longitudinally from the cardia to the pylorus, and
are least marked in the latter situation. When the stomach
is empty, the folds of the mucosa completely occlude the
cavity. The covering surface epithelium of the stomach is indis-
tinctly stratified; the innermost flat, horny layer and the col-
umnar layer are well marked, while the middle layers of cuboidal
epithelia are often wanting. The difficulty of obtaining for
examination the unchanged gastric mucosa of man is, perhaps, the
reason why the presence of flat, horny epithelia has been over-
looked. The columnar epithelium gradually loses its character,

Fig. 251. — Oesophagus op a Rabbit. Transverse Section.

E, horny layer; R, rete mucosum ; C, layer of colunmar epithelia; M, loose connective
tissue, with iujecteil blooil-vessels ; T, circular layer of striped muscles, wltli the adjacent
oblique and longitudinal layers, L, L i. Magnified 150 diameters.

and is transformed into the cuboidal epithelium of the gastric
glands.

The majority of the gastric glands are of the simple tubular
variety, though it often happens that two or more tubules empty
into a common tube of larger caliber, opening at the inner surface
of the mucosa. In the stomach of man, in the middle portions of
the mucosa, branching tubular glands are said to occur (Kolliker).

TUK DIUESTIVE TRACT.

:m

Siicli an a])i)oar}iiu'(' is somotimos produced by tul)ulo8 which run
t>l)li(iucly or in a windiufi^ course, whicli in vci'tical sections seem
to inoseuhite witli the periK'udieular tubules. The j^astric! glands
are linetl with euboidal epitlielium, with interspersed formations
of hiritice, ])ale, finely granular ei)ithelia, to the presence of which
1\. Heidenhain and A. Kollet drew attention. The Greek denom-
inations >.;iveu to them l)y the last-named ol»server are super-
fluous in the face of the fact that the ditference in the appearance
of the epithelia is due simply to
the process of secretion. The
coarsely graiiular, indistinctly nu-
cleated, epithelia are for the time
being not engaged in the produc-
tion of the mucous secretion
termed pepsine ; wdiile the large,
pale, distinctly nucleated epithe-
lia are laden with it. Pepsine
consists, in part, at least, of trans-
formed living matter of the epi-
thelia. By an accumulation of
liquid the bioplasson reticulum is
at tirst stretched, afterward torn,
and large portions of the bioplas-
son perish in the formation of
pepsine. By the rupture of the
cement investment, the secretion
is discharged into the caliber of
the tubule. As the glandular epi-
thelium forms only one layer, the I'lo- -■">-
swelled epithelia bound the caliber
in the same manner as the ordi-
nary euboidal ones, and it is only
in a surface section of the tubule
that the swelled epithelia appear
near the basement layer of the connective tissue, as if covered
by coarsely granular euboidal epithelia. These relations are most
definitely marked in places where the same tubule is, owing to its
winding course, seen in longitudinal and transverse directions.
(See Fig. 252.)

The secretion of the tubular glands — the gastric juice — owes
its acidity to the presence of a small quantity of hydrochloric
acid. This reaction is obviously induced through the agency of

^-^

Gastric Glands from
THE Stomach of Man. Verti-
cal Section.

L, tiibuli' iu a lougitiKlinal ; T, tubule
in a transverse sectiim, lined by t'uboidal
eiiithelia; /', epitlielia laden with pepsine.
Maguitied 800 diameters.

596

THE DIGESTIVE TRACT.

the epithelia themselves, which obtain their material from the
alkaline blood. It should be borne in mind that gastric juice is
a product of living matter, and as such is beyond the reach of
chemical analysis. Chemists have tried in vain, so far, to
explain the production of gastric juice by complicated formulae
and ingenious calculations. The large number of Greek names
given to the artificial products in the chemist's retorts sufficiently
proves their want of knowledge in this matter. The solution of

the puzzle, why the acid gastric
'F juice does not digest the wall of
the stomach itself, has also oc-
cu])ied speculative minds to a
considerable extent, but no sat-
isfactory answer has as yet been
obtained.

The delicate fibrous connec-
tive tissue between the tubular
glands forms a basement layer,
which furnishes support for the
epithelia, and carries the blood-
vessels, which are very numer-
ous in the mucosa of the stom-
ach. The vascular plexus woven
around the tuljules is extremely
dense, and near the surface of
the mucosa composed of wide
-'^capillaries. (See Fig. 253.)

In transverse sections of the
pepsine glands, in which the
central cali])ers of the tubules
are best marked, the vascular
plexus is seen surrounding the
tubules, and, if injected with
colored gelatine, many of the
capillaries appear to be almost
in contact with the base of the
epithelial wreath. In such sections the relation between the
empt}^ and the laden epithelia is also marked ; in the portion
nearest the central caliber the latter are partly overlapped by
the former. (See Fig. 254.)

The tubular formations toward the pylorus have been de-
scribed as being mucous glands, without any decided anatomical

Fig. 253. — Mucosa OF THE Stomach
OP A Eabbit. Vertical Section.

F, laj-er of hornj' epitlielia; E, cuboidal
epitlielia ; P, epithelia laden with i)ei)8ine.
The delicate counective tissue between tlie
tubnlar glands containing injected blood-
vessels; A, artery: T'T', veins ; M, smooth
muscle-layer of the mucosa. Magnified 300
diameters.

TUK DKiKSTlVK TIIACT.

)U7

proof; here acinous iniicous <j:lati(ls l)('<jin to nj>])('nr, l)I('ii(liii<^
with those of the tluodemini.

The eoniieetive tissue of the luueosa of the stomach, esjjecially
in children, is composed hu-f^-ely of the m3^xomatous variety and
abundantly su})plied with lymph-corpuscles. Both in the fundus
and the pyloric portion of tlie stomach of man lynii)h-tissue
appears as follicli's and t>rou])S of follicles, which Ijy mistake
have been tenued " k'nticul.ir i;l:in(ls." Their number, however,
varies ii;reatly, and in the h^ealities where they exist pepsine
glands are not found.

The mucosa of the stomach has a nearly continuous layer of
smooth muscle-fibers, composed of circular and longitudinal
bundles ; the circular fibers send pro-
longations between the tul)ular glands.

The muscle-layers of the stomach
proper are of considerable width, and p
principally arranged in two layers —
an inner circular and an outer Ion- ^
gitudinal ; the bundles of both being
freely interlaced with ololique bundles.
The cii'cular layer produces the sphinc-
ter-muscle of the pylorus.

(5) The Small Intestine. In trans-
verse sections of the small intestine
the layers constituting its wall appear
as follows : fa J the mucosa, producing
reduplications above the level of the
inner surface, the vilti, and reduplica-
tions below the level of the inner siu'- siau^is; p, epitheiia ladeu with pep

- ,-,,-.-, •,,•77 7 X7 1 sine; (', couuective tissue between

ta,ce, the twomar intestinal gkinas ; (bj the tuimies, containing injected
the submucous lai/er, holding circular J^J"^;^^-''^****®^^- Magniiiea 30o diam-
and longitudinal layers of smooth

muscle-fibers, and a varying amount of lymph-tissue (the so-
called adenoid tissue) ; fcj the muscle of the intestine proper,
composed of a broad circular and a narrow longitudinal layer of
smooth muscle-fibers ; and (d) the covering peritoneum. (See
Fig. 2.55.)

The villi are reduplications of the mucosa, of a conical or cyl-
indrical shape, very long and narrow in portions where the mus-
cle of the intestine is contracted; broad and short, on the
contrary, where the muscle of the intestine is extended. In the
highest degi-ees of distension (by gaseous material) the inner

Fig. 254. — Mucosa of the
Stomach op a Eabbit.
Horizontal Section.

E, cuboidal epithelia of tlie tubular

598

THE DIGESTIVE TRACT.

surface of the mucosa is smooth, and no villi are perceptible.

Each villus comprises the following layers: (a) a covering col-
umnar epithelium ; (hjmyxoma-
fous connect ire tissue, forming
the central portion of the \'iUus;
in this are imbedded fcj delicate
-r Iongitudin((l (Briicke)and^/r/»s-
rerse (Moleschott) l)undles of
smooth muscle-fibers ; fdj a
rich plexus of capillary blood-
vessels^ and (e) a central lymph
or chyliferous vessel.

The epithelium is of the
columnar variety, with numer-
ous wedges or intercalated for-
mations between the conical or
cylindrical bodies. These are
separated from each other by
an envelope of cement-sub-
stance, which is traversed by
connecting filaments (see page
130, Fig. 44). The cement-
substance is well developed on
the free surface of the epithe-
lia, producing the so-called
" basal seam " of authors. This
seam consists of a thin and ho-
mogeneous layer of cement-
substance, studded with a
number of short, delicate rods,
which are plainly visible only
when, by imbi])ition of a liquid,
the epithelium is slightly swell-
ed. To the presence of these
rods Brettauer and Steinach
first drew attention, while Koll-
iker and Funke considered the
vertical striation of the basal
seam to be minute pore-canals.
According to the difference of
conception as to the structure

of the seam, some physiologists claim that the finest fat-granules.

Fig. 255. — Small Intestine of aDog.
Transverse Section. Blood-ves-
sels Injected.

V, villi; G, tubular intestinal glands; M,
longitmlinal muscle-layer of the mucosa; A,
lymphatic (adenoid) or submucous laj-er; Ji,
circular muscle ot the intestine, cut longitudi-
nally; i, longitudinal muscle of the intestine,
cut transversely ; P, peritoneum. Magnified
25 diameters.

77/ /•; Did h'sri I a; 77,'. 1 ct.

599

duriii;;: tlu' proci'ss of absorption, arc taken into tlic cpitliclia
heticeen the rods, whOe others maintain that the rods themselves
take lip tlie t'at-^'ranules. Above the eolunmar epitlielia flat
endothelial formations have ])een deseri})ed, constituting the
outermost investment of the connective tissue (Watney, Krause,
Debove).

The manner in wliicii Ii([uids arc taken u[> into the blood- and
lympli-vessels of the villus is by the active participation of the
columnar e])ithclia (Spina). During absorption, especially shortly
after fatty food has been eaten, the interior of the villi and also of

Fig.

256. — Villus from the Small Intestine of a Cat,
Vertical Section. [Published in 1868.]

^.myxomatous (so-callwl ailcnoid) tissue; in its center the lymph-vessel, bounded by
smooth niusclefjbers and filled with fat-granules; F, cleft between the columnar epithelia, in
connection with the central lymph- vrssi-l. Majinified 800 diameters.

the covering epitheliiun is found to contain a large quantity of fat-
granules of different sizes, and the conclusion arrived at by Gruby
and Delafond was that the fat-granules were first taken up by
the epithelia, which convey them into the interior of the villus.
Since that time, most of the physiologists have attempted to
explain the absorption of fat from the basal surface of the epi-
thelia ; but the whole process is as yet an unsolved puzzle. We

600

THE DIGESTIVE TRACT.

could understand the penetration of fat-grannies between or into
the rods, but how the horny and apparently solid layer of cement-
substanee, serving as a base for the imj^lantation of the rods,
could be penetrated by fat-granules is not intelligil)le.

In 18G8 I published the results of my researches during a
whole year (1. c, see page 401). I drew attention to the fact that
in specimens of uninjured villi, independently of furrows pro-
duced by contraction, the apices look as if split, often giving exit
to a mucous mass, or a portion of myxomatous tissue of the vil-
lus, and that in true vertical sections of the villi there are gaps
seen between the epithelia which are in direct connection "with

Fig.

257. — Villus from the Small Intestine of a Guinea-pig.
Fresh Specimen. [Published in 1868.]

V, vacuole in the columnar epiUiellum ; CV, granular (chloropIij-U?) corpuscle in a vacu-
ole; C, granular (cliloroplij'll ?) corpuscles in the myxomatous tissue; B, capillary blood-ves-
sel. Magnified 800 diameters.

the central lymph-vessel, as proved, especially when both are
filled with fat-granules. (See Fig. 256.) Whenever colored liq-
uids are injected into the lymphatics of the small intestine
(before injecting the blood-vessels), it has long been known that
the colored mass escapes through the apices of the villi into the
intestinal canal. I have examined the small intestines of sixty-
eight guinea-pigs, and found, in a large majority of the villi of

TllK DKiKSTlVK TRACT. (JUl

those animals, pecnliar prannlar bodies, usually aecuninlatcd
al(»ii«i' tlii^ ai)ices, Imt occurring- also in the vacuoles of the epi-
thelia, or in fj^oblet-like formations produced by the epithelia. A
few ^uinea-pi^s whic^h I examined in New- York exhibited the
same fV)nnations — formations that do not occur in the intes-
tines of other lierl)ivorous animnls I had examined. These are
clusters composed of a pale granular nuiss, containing a num-
ber of green or greenish-yellow granules, with a high degree of
refraction ; I also found isolated granules of various sizes. (See
Fig. 2:,7.)

The differences in the number, the color, and appearance of these bodies
were found to vary according to the following conditions : Embryos of
guinea-pigs, examined a few days before birth, had no coi"puscles in their
villi. Newly born guinea-pigs, one to two hours after birth, showed no cor-
puscles ; but sixteen to twenty-four houi*s after birth, the animals being fed
with oats, the villi showed a number of yellowish-green bodies, with fine
gi-anules. All the animals of a more advanced age exhibited the green cor-
puscles in the villi. The color was evidently dependent on the vegetable
food. After feeding with fresh blades of gi'ass a light chlorophyll-green was
seen, and a light, pure yellow color appeared after feeding with the flowers of
leontodoH taraxacum ; a dim yellowish-green was observed after a continued
administration of vegetables. When the stomach remained filled with food
the contents, from the cardia toward the pylorus, showed all shades of gi'een
to yellow-green ; this green shade remained for a month or a month and a
half after the fresh vegetable diet had been stopped and amylaceous food had
been exclusively administered. A light yellow-green color was mainly
observed in autumn and after feeding with straw. If blue aniline was mixed
with the food the gi-anules assumed a dark bluish-gi-een. After administra-
tion of starchj^ food for one and a half to two months, the granules were col-
orless and the animals died, e\-idently fi-om starvation ; it was only under
these conditions that the stomach was found empty. The granules were
largest after feeding with the young leaves of plants, and smallest after
administration of dry vegetable food or oats. The age of the animals had no
influence upon the color and shape of the granules. In two instances I found
such granules in mesenteric ganglia also.

Unquestionably the granules are chlorophyll granules, and
their coloring matter is chlorophyll ; for it can be extracted with
alcohol, and assumes a yellowish -brown color when preserved in
chromic acid. Very probably these bodies are vegetable bio-
plasson, having left the shell of cellulose. But in what way did
they penetrate into the stroma or central lymph-vessel of the
villus?

In guinea-pigs several houi's old I found villi containing three
or four corpuscles in their axes, the uppermost of which was
located in a craterif orm depression in the middle of the apex. Not

602

THE DIGESTIVE TRACT.

infrequently the central canal contained only a row of these
corpuscles, as proved by vertical sections through villi, in speci-
mens hardened in a solution of chromic acid. Sometimes in fresh
specimens the green bodies wer-e seen, as if incarcerated at the
apex in an intra-epithelial canal. By gentle pressure on the
covering-glass some of the bodies could be forced out from
the apex (see Fig. 258). From these phenomena in the small

Fig. 258. — Villus from the S .iall Intestine of a Guinea-pig.
Fresh Specimen. [Published in 1868.]

C, granular (clUoiopliyll 0 coipiiscle, forced out from tht> interior of the villus; O, such
corpuscles filliug the cleft between the columnar epitheliu ; B, caiiillary blood-vessel. Mag
uified 800 diametei's.

intestine of guinea-pigs, from anatomical facts, and a number of
successful experiments in bringing extraneous matters (carmine
and aniline granules) into the lymph-vessel of the villus from
without, it would follow that the apex of the villus has in its
epithelial investment one or two perforations in direct connec-
tion with the central lymph- vessel, which serves to take up solid
material, mainly fat-granules. J. Nath. Lieberkiihn, in 1745,

TllK DUiKSTlVK TJiACT. G03

described ^' ampuUsv '' in the villi, wliicli, by some physiolojifists,
were considered to be wideniii«::s of the chylifcrous vessel at the
base of the villus. / luii'c ttuith' the presence of such oj)eitini/s cer-
iainhf probable^ even though positive proof's of their existence are
still wantimj.

Alonj; the epithelial investment of the villi «,'()blet-like forma-
tions are t)fteu seen, more nnmcrous in animals having an in-
creased mucous discharge from the intestine — /. v., diarrhoea. In
ISGS I maintained that these formations wei-e the shells of cement-
sul)stanee, after the contents — the mucus — had l)een emjjtied
out. This theory was contrary to the ideas of some observers, who
claimed that the goblets had been artificially produced, or were
specific secretory organs. Donders and Kcilliker had, previously
to the publication of my views, descril)ed these formations as con-
nected "vvitli the secretion of mucus, and this idea proved to be
correct.

The epithelial investment of the mucosa of the intestine forms
tubular glands, the intestinal glands or so-called er/jpts of Lieber-
l-iihn, which are located beneath the level of the mucosa, and,
being more numercms than the villi, empty by minute openings
around the l)ase of the villus. Their lining epithelium is col-
unmar, exhibiting the same basal seams as those covering the
villi. The intestinal glands are absent in localities where lymph-
follicles are imbedded in the mucosa.

The mucosa of the duodenum, chiefly in its upper third, holds
racemose glands, which are situated below the level of the lower
extremities of the intestinal glands ; these are called Brunner's
glands, and their secretion is considered to be mucus. In the
descending portion of the duodenum they gradually become
scantier, and especially so below the openings of the bile-duct.

The mucosa of the small intestine is supplied with a doable
layer of smooth muscle-fibers, independent of the muscle-layers of
the intestine itself. The innermost is circular, running between
the tubules and penetrating through vertical prolongations the
myxomatous structure of the viUi, where several delicate bundles
are formed by it ; the outer muscle-layer is longitudinal, being
in most localities decidedly broader than the circidar layer.
Transverse sections of portions of the small intestines, hardened
by ha^'ing been jjlaced in a solution of chrondc acid immediately
after the animal's death, plainly show that where the muscle of
the intestine is broad, consequently contracted, and the caliber
of the intestine narrow, the \alli are elongated and thread-like or

6(k THE DIGESTIVE TBACT.

cylindi'ical in shape ; while, where the muscle is extended, the villi
are seen as conical or blunt elevations. The vWli corresponding
to the place of attachment of the mesentery are always the
smallest, those on the opposite surface the largest. The lobate
form of the short conical y\\M is due to the contraction of the
bundles of smooth muscle-fibers contained in the myxomatous
stroma of the ^'illus. as first intimated by Briicke. In 1868 I con-
cluded, therefore, that the shape of the \illi of the intestine is not
fixed, but varies between that of a cylinder and that of a cone,
depending on the contraction or extension of the intestinal tube,
the peristaltic motion thus producing a continuous change. I also
concluded that the muscle-layers of the intestine proper are
antagonistic in their action to the muscle-layers of the mucosa ;
in other words, when the muscle of the intestine is in the highest
degi'ee of contraction, the muscles of the villi, being prolongations
of the muscle of the mucosa, are extended, and vice versa. An
extended \t11us has a smooth surface ; the lobation begins as the
villus changes its shape from the cylindrical to the conical. In
the extended condition of the ^'iIli, — i. e., when the muscle of the
intestine is contracted, — the presumed openings at the apices of the
villi are gaping and ready to absorb the fat which is present as an
emulsion in the considerably narrowed caliber of the intestine,
and reduced to extremely small granules, perhaps, by the me-
chanical action of the rods of the basal seam of the epithelia. As
soon as the contraction of the muscle of the intestine ceases, the
contraction of the muscle of the mucosa sets in, the villi become
retracted, and the openings at theii* apices closed. By this proc-
ess the absorbed fat will be carried backward into the lymphatic
or chyliferous system. Probably there is also an antagonism
between the circular and longitudinal layers, both of the mucosa
and the intestine.

The mucosa of the intestine immediately above the muscle
is abundantly supplied with lymph (so-called adenoid) tissue,
which produces a continuous layer and is accumulated in the
solitaiy follicles and in groups of the aggi-egated follicles — the
so-caUed Peyer's patches. E. Briicke first drew attention to the
IjTnphatic nature of these formations. The solitary follicles
appear to the naked eye as flattened protrusions above the level
of the mucosa, or as bare spots, or even as shallow depressions.
The columnar epithelium covering the surface of the follicle is
shorter than the epithelium covering the villi. Villi are wanting
in those parts of the mucosa which are furnished with solitary

THE 1)1 (11-: STIVE JltACT.

GU.J

follicles and ]i!it('hos; the tubular intestinal glands within the
tei-ritory of a t'ollicle may be either absent or j)resent oidy in
small numbers. In the eontraeted porti<jns of the intestine, the
follicle, i)rotrudinji^ as a conical elevation, is overlapped^ by the
surrounding; villi ; while in the extended portions the follicle is
fattened and the villi stand at a certain distanc(^ around it. The
longitudinal layer of the muscle of the mucosa is perforated, cor-
responding with the extent of the follicle, and surrounds its per-
iphery. (See Fig-. 259.)

Fig. 259. — Small Intestine of a Kabbit. Vertical Section in
THE Longitudinal Axis. Lymph-vessels Injected.

T, villi ; M^^, loii^itiulinnl muscle-layer of the mucosa ; F, lyinplifoUicle ; M, fibrous con-
nective tissue; T, eiicular muscle of the iutestiue, in transverse section; L, longitudinal
muscle of the intestine, in lon^ifitudinal section ; P, peritoneum. Magnilied 25 diameters.

(6) The large intestine is similar in structure to the small, but
destitute of villi ; its mucosa, being of a myxomatous character,
shows elevations and folds arranged in a circular direction. The
tubular intestinal glands are larger than in the small intestine.
The lymph-tissue is either distributed uniformly in the submu-
cous layers, or is accumulated in the follicles, which are, it is

606

THE DIGESTIVE TBACT.

maintained, in no way connected with the chyliferous vessels.
The snbmucous portion of the vermiform appendage has a very
broad layer of lymph-tissue. While the muscle of the small intes-
tine is almost uniformly distril)uted throughout the tube, and the
circular always shows gi-eater development than the longitudinal;
in the large intevstine, on the contrary, the outermost longitu-
dinal muscle-layer is imperfectly developed, but in certain places,
called trfiiia, accumulates in ribbons. At the point of the junc-
tion of the ileum and coecum the circular muscle-layer enters
the formation of the valvula Bauhini, while the longitudinal
layer directly passes from the small to the large intestine.

j/j-

Fig. 260.— iw

^^.^:%^

:>i wr A Dog. Vertical Section

IN THE Longitudinal Axis.

JF", colnmnar epithelinm ; A , acinous mucons glands : MM, longitudinal mnscle-layer of
the mncosa ; C, submucous fibrous couuective tissue ; MI, circular muscle of the intestine, in
transverse section. Magnified 300 diameters.

The mucosa of the rectum exhibits reduplications like that of
the large intestine, and is, in its lower portions, supplied ^vith a
varying number of racemose glands, especially well developed in
the rectimi of the dog. (See Fig. 260.) The internal sphincter is
constituted by an aggi-egation of the smooth circular muscle-
fibers, while the external sphincter is composed of striated mus-

Till': DIGESTIVE TRACT. 007

cle-fibers in a ciivuliir and plcxit'orni arran<i('nuMit. Both cin-iilar
and lonii^itudinal layers are uniformly distributed throughout
the wall of the rectum, attaining tlicir greatest widtli near the
anus. The transition of smooth to striped muscle-fibers is
gradual.

lilood-vesseh of the Tntpsf'tnes. According to C. Toldt, the dis-
tribution of the blood-vessels in the intestines closely resembles
that of the stomach, their arrangement being nearly identical in
the stomach and the large intestine. The arfpfioJrs send branches
to the peritoneum and pierce the longitudinal muscle-layer, be-
tween which a further division takes place by the formation of
elongated capillary meshes, for the supply of the two muscle-
layers of the intestine proper. After having perforated the
circular muscle, — always, of course, in the external perimysium
which separates the larger muscle-bundles, — the arterioles reach
the submucous layer, producing, by repeated bifurcations and
anastomoses, an extended vascular plexus. Finally, the arteri-
oles penetrate the longitudinal muscle-layer of the mucosa and
form the terminal arterial plexuses extended beneath the tubular
glands, from which arise the terminal arterioles for the supply of
the uppermost portions of the mucosa. In the stomach and the
large intestine the capillaries are woven around the tubular
glands, and widen beneath the surface epithelium to double their
original diameters in circular loops around the openings of the
tubules. From these superficial capillaries arise the veins, which,
at regular intervals, pass downward between the glands and
empty into venous plexuses within the mucosa. The efferent
veins arising from this plexus accompany the arteries downward.
In the small intestine the arterioles penetrate the myxomatous
tissue of the villi; each villus contains one or two arterioles,
which branch very freely into capillaries. The latter are in con-
nection with the capillaries of the tubular glands. The veins
originate at the apices of the villi from slightly widened capillar-
ies. (See Fig. 255.) In the duodenum the acinous glands are
supplied with capillaries of their own, and so are all lymph-
follicles of the small and large intestine.

The lymph-vessels of the intestines produce a separate capillary
plexus for the muscle-layers and for the mucosa. The former
was first described by Auerbach, who found that the lymphatics
collect into the so-called interlaminar lymphatic reticidum, lo-
cated between the longitudinal and circular muscle-layers. Flat
plexiform extensions of Ipnphatics exist in the submucous layer

608 THE DIGESTIVE TliACT

beneath, and in the mucous layer above, the longitudinal muscle
of the mucosa, the latter plexus l)eing situated at the bottom of
the tubular glands; both are connected by oblique branches
piercing the muscle-layer. The lymphatics arising from the sub-
mucous layer are supplied with valves ; they leave the intestine at
the insertion of the mesentery. The connective tissue of the peri-
toneum possesses a lymphatic capillary system of its own, produc-
ing the so-called subserous plexus. The lymphatics form sinuses
around the gastric glands (Loven), a number of which are in-
cluded between two lymphatics. The uppermost sub-epithelial
lymphatics are plexiform, or originate as pointed tubules. Sim-
ilar relations are found to exist in the large intestine. In the
small intestine the beginnings of the lymphatics are found in the
central portions of the villi, either as a wide, single tubule or as two
or more longitudinal tubules with transverse connections. Even
single tubules may, at the apex, produce a loop, from which, in
injected specimens, pointed prolongations between the epithelia
are often seen arising. (See Fig. 259.) The lymphatic or chyl-
iferous vessels of the villi have a complete lining of endothelia.
A closed reticulum of lymphatics surrounds the lymph-follicles,
though it is generally believed that, in the rabbit's intestine,
the follicles are encircled by a sinus.

The nerves of the intestines are of both the medullated and
non-medullated varieties. They form a plexus above the peri-
toneum, and, after having traversed the longitudinal muscle-
layer, give rise to the plexus l)etween the longitudinal and
transverse muscle-layers (Auerbach's plexus), which is composed
of reticular extensions of nerves, with numerous interspersed gan-
glionic nerve elements. From the nodular ganglia of this plexus
numerous non-medullated nerve fibrillar emanate for the supply
of both muscle-layers. A number of nerve-fibers pass through
the perimysium of the circular muscle to the submucous layer,
where again a plexiform extension is produced, with interspersed
ganglionic elements (Meissner's plexus). Its nerve branches sup-
ply the mucosa and the muscles of the mucosa. The globular or
oblong ganglionic elements are decidedly larger in the submucous
than in the intermuscular plexus. (See Fig. 2G1.) In what man-
ner the ultimate nerve fibrillae terminate is not known.

(7) The salivary glands are large racemose glands which
secrete a watery or mucous liquid, and empty either into the
oral cavity (the parotid, submaxillary, and sublingual glands),
or into the duodenum (the pancreas). According to A. Heiden-

77/ /•; i>i(i i-:sri i •/•; tk. i ( t.

G09

huiu iiiul Jjuvclowsky, tlit'iv arc ^luiuliilar t'onnatiuus of the race-
mose variety, such as those foiiiul in the nasal mucosa, wliich
are called scrons (/lands, and wliicli produce n watery secre-
tion. The parotid gland and the pancreas may alsolic grouped
with this variety. Others — the sublingual gland — discharge a
mucous, viscid li(juid, while the secretion of the su])maxillary
is partly serous and partly mucous. The difference's in the
appearance of the glandular epithelia may })e understood when
we recall the process of mucous secretion in general. (See page
:J29.) Epithelia not participating in the process of secretion are

Fig. 261. — Nerve-Plexus of the Small Intestine op a Cat.

MP, Mt'issner'.s plexus ; S, submucous fibrous connective tissue ; T, circuliir muscle of
the intestine, in transverse section; AP, AueibiK'li's plexus; i, lougituilinal muscle of the
iutestine, in longitudinal section. Magnified 8l)() diameters.

found, according to R. Heidenhain, immediately beneath the
structureless layer, and are termed by him the bordering cells,
being the reserve from which epithelia are supplied to take the
place of those which were destroyed by the secretion of mucus.
Such reserved epithelia are not found in serous glands — for in-
stance, in the parotid. Different portions of the submaxillary
gland exhibit both varieties of the epithelia, which blend with
39

610 THE 1JIGE:STIVE TRACT.

eaeli other. The pancreas has the smallest acmi, and here the
epithelia are found coarsely granular, even homogeneous toward
the structureless layer. Some observers have erroneously claimed
that this gland belongs to the tubular variety. The ducts of all
salivary glands are lined by columnar epithelia. The pancreatic
duct is provided with acinous mucous glands. The columnar
epithelia, in the smaller ducts chiefly, show a delicate longitudinal
striation, which is most distinctly marked in the portion of the
epithelium nearest the structureless layer. The significance of
this striation will be dwelt upon in the article by H. B. Millard,
treating of the epithelia of the kidney. In the tubules of the
ducts inosculating with the acini, the epithelial hning shows
slight differences in different salivary glands.

Saliva, transfeired to the slide in a perfectly fresh condition, and covered
with a thin covering-glass, is an excellent specimen for the study of bioplasson
bodies. Besides flat epithelia from the oral cavity and a varj"ing number of
leptothrix, we find the salivary corpuscles — i. e., the former tenants of gland-
ular epithelia. These are nucleated plastids exhibiting the reticular struct-
ure and amceboid movements, at usually the ordinary temperature of the
room. To study the form changes, it is ad^•isable to sketch on paper, from the
beginning of the investigation. Large, swelled corpuscles, with pale, vesic-
ular nuclei, may also be found, containing granules which, being the remnants
of the torn reticulum, are in an active so-called •' molecular " motion. The
nimiber of such hydropic corpuscles increases with the duration of the obser-
vation under the microscope. At last both the active and hydropic corpuscles
burst, and masses of detritus or clusters of granules result. The nuclei of the
flat oral epithelia also exhibit the reticular bioplasson structure, and are
obviously endowed with vitality, which endures for some time after the horny
change of the rest of the epithelium has taken place (Strieker).

In thrush (see page 44), the whitish patches consist of an aggregation of
leptothrix, oidia, and scanty-chambered mycelia ; in short, the constituent
elements of mildew.

In catarrhal stomatitis, the number of salivary corpuscles is considerably
augmented, and the amount of the bioplasson they contain increased, as
shown by their coarser gi-anulation. Such corpuscles attain all the appear-
ances of pus-corpuscles, and may be so termed. Stringy threads of mucus are
also found in even slight degrees of inflammation of the mucosa, caused by
mucous transformation of bioplasson before its ejection from the epithelia,
and coalescence of a number of mucous globules. A small amount of blood
is usually found intermixed.

Jn croupous inflammatio)i, the grajnsh white, so-called "pseudo-membran-
ous " formations covering the swelled and considerably hyperaemie mucosa,
consist of a fibrinous exudation, which under the microscope appears as a
felt-work of sometimes narrow, sometimes broad, granular fibrils. (Repre-
sented on page 516, Fig. 212.) In the meshes of this irregular felt-work scanty
bioplasson bodies are found, which may be considered either as nuclei of
former epithelia, destroyed in the production of the croupous exudate, or as

Tin-: DIGESTIVE TRACT. {\\l

euii'^ratiHl colorless blood-corpusdos (so-called " leucocytes "). The deter-
mimitiou as to the particular source of these corpuscles, in the present condi-
tion of our knowledge, is iinj)()ssilile. The (Uphtheritic ('xiidation is of exactly
the same character as the croupous ; its nature is detorininod by its deep site
in the tissue of the mucosa, and is often recognizable under the microscope by
the presence of isolated globular clusters of lymphatic (adenoid) tissue, from
which putrefaction starts. The globular nests filled with micrococci originate
from such clusters of lymphatic tissue.

XVI.

THE TEETH.

EVERY tooth in the socket of the jaw is in close connection
with the surrounding structures and is composed of living
tissues. Morbid processes, especially caries, produce more or less
painful sensations in the tooth, even before the pulp-ca\dty has
been invaded. The cutting with dental instruments of healthy
portions of the tooth is an unpleasant and even painful process
to the patient, and especially so at the boundary between the
enamel and the dentine, and in the neck of the tooth. For-
eign bodies, such as fillings of any description, if brought in
contact with dental tissues, set up an inflammatory condition,
resulting in the so-called ''consolidation" of dentine — a process
which, a century ago, was observed by Gothe in the dentine of
the elephant's tusk after a bullet had been accidentally driven
into this tissue. The sensation called " putting the teeth on
edge," caused by eating sour fruits, is another proof of the pres-
ence of life in the tooth. All former observers, however, — though
some of them have maintained the presence of nerves in the
dentine, — failed in demonstrating the liA-ing matter in its most
intricate distribution, partly omng to the faulty method applied
for microscopic research, and partly to the lack of knowledge in
the arrangement of living matter in other and kindred tissues of
the body. Dry specimens, formerly resorted to, are only mum-
mies in which a frame of lime-salts is left, but the soft parts — the
seats of life — have disappeared. Oiu* present knowledge of the
minute anatomy of the teeth, as displayed in the following arti-
cles, is largely due to the improved methods applied for research.

TIIK TEETH. 013

Dentine, Cement, and Enamel. By C. F. W. B»)deckek, D. I). S., M. I). S.*

Methodt. The best method for preparation of bone-tissue for microscopical
purposes is doubtless the treatment witli chromic iicid sf)hiti()n of tlie streii^i^th
of II half to one per cent. The same treatment has repeatedly been resorted
to by different investigators of tooth-substance. I have used this solution
extensively for this purpose, with precautions suggested by the experience on
bone. These are : to immerse only a few teeth in a large vessel with a con-
siderable amoimt of chromic acid solution ; to renew the same every third or
fom-th day, and add, to enforce the action of the fluid, very small quantities
of dilute hydrochloric acid. By this treatment the teeth, after a few months,
become dark gi'een from the reduction of the chromic acid to the sesquioxide
of chromium. This method is doubtless the best for softening teeth, although
the chi'omic acid softens the cement and dentine only to a certain depth, so
that a tooth kept in the chromic acid solution never is fit to be cut through in
its whole substance at one time. The sections so obtained are ready for
staining ^vith carmine or ha?raatoxylon, and after they have been immersed
in and washed with distilled water, also for staining with chloride of gold.

The gi-eatest objection to the chromic acid treatment is that enamel
never can be obtained in connection with the dentine. If hydrochloric acid
has lieen used, in addition to the chromic acid solution, the enamel is almost
completely dissolved. If chromic acid alone has been used, the enamel
becomes so brittle that it crumbles into small particles imder the knife.

Lactic acid acts upon teeth, if diluted sufficiently, by dissolving the lime-
salts much faster than chromic acid. Specimens prepared in this way, how-
ever, in my experience, are not distinct enough for study with high powers.

The only method which enabled me to obtain specimens of teeth provided
with all hard tissues is the following : A fresh tooth, or one kept a short time
in chromic acid solution, is sliced under water by a watch-spring saw, and
groimd as thin as possible upon a corundum-wheel of a lathe, always being
kept under water. The lamella thus obtained should be placed in a large
quantity of chromic acid solution, of the strength of half of one per cent., for
one or two days, with the Anew of hardening the soft parts of the tooth and
dissolving the lime-salts. After this the specimen may be stained with car-
mine, haematoxylon, chloride of gold, etc., as above described, and mounted
in dilute glycerine. The saturated solution of picric acid in water may also be
used for the decalcification of a gi-ound slice of a tooth.

Dentine. We know that the basis-substance or matrix of the dentine is
analogous to that of bone, \'iz. : glue-yiekling, and at the same time infiltrated
with lime-salts. We learned from the researches of E. Neumann that the
basis-substance is denser on the walls of the tubuli, and more resistant to the
action of strong acids, which cause the appearance of a sheath around each
tubule after the solution of the intermediate substance of the mati'ix between
the tubuli.

With low powers we cannot see in the dentine anything but the tubul;,
which I propose to term hereafter dentinal canaliculi. These, as is well known,
run in curved sigmoidal lines from the boundary of the pulp-ca\'ity to the
periphery of the dentine ; they are directed obliquely upward in the crown,
and assume a more horizontal direction in the region of the neck, while in the

-* Extracted from tlie author's essay, "The Distriltutiou of Living Matter in Hiiiuan Den-
tine, Cement, and Enamel." The Dental Cosmos. Pliiladelphia, 1878 and 1879.

614 THE TEETH.

root they remain horizontal or sometimes turn downward to a varying
extent. Besides the main sigmoidal ciu-vature, each individual canaliculus
exhibits a more or less wavy course in its way through the dentine, and the
individual curvatures are, as a rule, very marked on the outer periphery of
the dentine.

The dentinal canaliculi reach the outer surface of the dentine only on the
circumference, which is covered by enamel, while on the periphery coated by
cementum, including also the neck, the canaliculi terminate before reaching
the eementum, and are replaced by a fine, granular basis-substance greatly
varying in its width. The distribvition of the dentinal canaliculi is in the
great majority of teeth uniform throughout the dentine, although exception-
ally I have met with specimens of dentine in which there were smaller or
larger territories devoid of dentinal canaliculi, which latter look as if arranged
in bundles or groups within the basis-substance.

Each canaliculus contains a dentinal fiber. Longitudinal sections of den-
tine, stained with carmine or chloride of gold, if examined with high powers
— from 1000 to 1500 diameters (immersion lenses) — exhibit the following :
The canaliculi of the dentine run in a more or less wavy course through the
basis-substance, and are, as a rule, bifurcated only on the periphery of the
dentine, both toward enamel and eementum. Each canaliculus contains a
central, slightly beaded fiber, which on its whole periphery sends delicate,
thorn-like elongations through the light space between the central fiber and
the wall of the canaliculus. The thorns are distinctly conical, their bases
being attached to the dentinal fibers, and their points directed toward the
basis-substance. The smallest thorns spring in an almost vertical direction
from the dentinal fiber, while somewhat larger offshoots may run obliquely
through the basis-substance, and directly unite neighboi"iug fibers with each
other in the vicinity of the enamel and eementum.

The basis-substance shows a distinct net-like structure. The light spaces
surrounding the dentinal fibers send delicate elongations into the basis-sub-
stance, in which, through repeated branching, a light net-work is established,
the meshes of which contain the decalcified, glue-yielding basis-substance.
The finest offshoots of the dentinal fibers can be traced only into the mouths
of the elongations of the canaliculi ; on the periphery of the latter, owing to
their great delicacy, the offshoots are lost to sight. Coarser offshoots of the
dentinal fibers, at the localities mentioned before, traverse the basis-substance
within its light net-work, at the same time uniting dentinal fibers directly,
and sending slender conical offshoots into the light net-work of the basis-
substance. (See Fig. 262.)

The dentinal fibers are either in direct connection with coarser offshoots
of the bioplasson bodies of the eementum, or the light net-work of the basis-
substance of the dentine is in communication with that of the basis-substance
of the eementum. The latter condition prevails on the periphery of the
neck of the tooth, where the basis-substance of the dentine is not pierced by
larger offshoots of the dentinal fibers, but only by a delicate net-work,
through which the connection between dentine and eementum is indii-ectly
established.

In cross-sections of dentine the dentinal canaliculi are visible in the shape
of round or oblong holes ; the center of each is occupied by the dentinal fiber,
which has the shape of a small, roundish dot. Again we see that the per-
iphery of the dentinal eanaliciilus is sharply marked, and repeatedly inter-

THE TEKTll.

615

rujitod, by \\^\\t lines k'iuliii<? into tlio liglit not-work which pierces the
l>asis-substance between the ciuiiiliculi. Tlio ceiitnil fibers look very distinct
and dark violet in speciniens staine<l with chloride of K<»hl, and send slender,
conical, radiated olTslioots tliroiifjh the surronndint^ dentinal canaliculi,
respectively, toward the niontii of the liglit interrnptions in their walls. In
directly transverse sections, one, two, or sometimes even three, such offshoots
can be seen in a star-like arraiif^ement. Each offshoot sprinj^s, with a broad
base, from the central dentinal liber, wliile its pointed end always is directed
toward the perforation in the wall of the canaliculus, wliere, as a rule, it is
lost to sight.

Toward the boimdary between dentine and enamel, and dentine and
ceraentnm, as is well known, the dentinal canaliculi ramify, and according to
their ramilications also the dentinal fibers bifurcate, becoming thinner the
nearer to the surface of the dentine. Both longitudinal and transverse see-

cgCTpr-»r}ir7nf5'[r"r:^jr-«=«|np-jpi^i^-;^jp

Fig. 262. — Root of Molar. Stained with Chloride of Gold.

D, (Icntine; C, cement, with plastids brancUinff and unithiiS; F^, dentinal fibers, witli tbi-ir
transverse offshoots ; F^, ramification of dentinal fibers and tlieir union witli the offshoots of
cement-corpuscles. Magnified 1 200 diameters.

tions of this part of the dentine show details identical with the main mass of
the dentine, the only difference being that, near the periphery of the dentine,
the fibers are more delicate and more closely packed together. (See Fig.
263 A and Fig. 263 B.)

In some teeth I have met, on the periphery of the dentine of the crown,
with the so-called " intei'globular spaces" (Czermak), which may be consid-
ered as remnants of the embryonic condition of the dentine. They represent
lacunas of gi-eatly varying sizes, bounded by ciu-ved lines, the convexities of
which are directed toward the central cavity. These spaces sometimes con-
tain bioplasson — /. e., embryonal elements which have not been transformed

616

THE TEETH.

into basis-substance and not calcified. The dentinal fibers enter the bioplas-
son bodies, and each fiber is united with the net-work of these bodies by
means of delicate, thorn-like projections. At other times the basis-substance
of the dentine is developed within the interglobular spaces, but devoid of
lime-salts. In this instance the dentinal fibers, without investment and with-
out changing their course, pierce the basis-substance and send offshoots to
this through the surrounding light spaces.

The dentine shows peculiar formations in general, though not constantly,
as instanced when approaching the enamel and cementum. These formations,
however, being in close relation to the covering tissues of the tooth, I prefer
to describe in the chapter on cementum and enamel.

Cementum. It has been long known that there exists a striking analogy
between the structures of the cementum and bone.

If we consider the central or pulp canal of the tooth as a formation anal-
ogous to a Haversian canal, containing blood-vessels, nerves, and medullary
tissue, then the surrounding cementum corresponds to a Haversian system of
ordinary bone, between which and the pulp-canal there exists an intermediate
stratum of dentine.

,""i*

{^t

Fig. 263 A. — Ckos.s-Section of
Dentine of Incisor. Stained
WITH Chloride of Gold. Main
Mass op Dentine.

F, dentinal canalicnU with the central
dentinal fiber, tlie latter with star-like off-
shoots ; R, the basis-substance between the
canaliculi, pierced by a delicate light net-
work. Magnified 2000 diameters.

Fig. 263 B. — Cross-Section of
Dentine of Incisor. Stained
with Chloride of Gold. View
FROM Outer Periphery of Den-
tine, NEAR Enamel.

F, dentinal canaliculi with the central
dentinal fibers, tlie latter witli star-like ofl'-
slioots ; a, the basis-substance between the
canaliculi, pierced by a delicate, light net-
work. Magnified 2000 diameters.

The zone of dentine is not present all around the pulp-cavity on the apices
of the roots; there the cementum, being the outermost layer of the tooth,
directly lines the cavity.

Delicate parallel striations are to be seen in the cementum, identical with
the lamellae of a Haversian system, and, as a rule, more plainly marked near
the periphery than toward the dentine.

Within the basis-substance of the cementum there are numerous branching
spaces, in correspondence with the lacunae of bone. The offshoots of these
spaces in the cementum, like the spaces themselves, are very marked in dry
specimens, because of their being filled with air. In chromic acid specimens,
on the contrary, the offshoots are much less prominent, and the less the more
thoroughly the decalcification has been effected by the acid. No essential
difference is noticeable between the lacunae and canaliculi of ordinary bone
and those of the cementum ; in both tissues there exists a great variety as to

THE TKKTIl. (117

the gencnil arraiif^ement, the size uf the hieuiue, ami the iiuinber anil ramifi-
cations of their offshoots.

The walls of tlie lacuna? anil the coarser offshoots, if viewed with a liifj;hly
magnifyiiifT lens, appear interrupteil at their peripheries by light spaces, whieli
lead into a light, delicate net-work, piercing the whole basis-substance to
such an extent that only the meshes have to be considered as the fields of cal-
cified glue-Welding basis-substance. Each lacuna contains a plastid with a
central nucleus — the cement-corpuscle. The nucleus sometimes is relatively
large and surrounded only by a narrow seam of bioplasson ; while in some
small lacuna? a body of the appearance of a nucleus is present without a
noticeable amount of surrounding bioplasson. The net-like structure of the
plastids is plainly visible on all cement-corpuscles. From their periphery con-
ical offshoots arise, the coarser of which penetrate into the larger offshoots of
the lacuna^, while the finest offshoots traverse the light rim between the wall
of the lacuna and the periphery of the plastid, being directed toward a light
interruption on the boundary of the lacuna.

Cement-corpuscles, on the average, are round or spindle-shaped bodies,
the long diameter of which corresponds to the direction of the lamellae. In
teeth of juvenile and middle-aged persons we meet with cement-corpuscles
siu'passing three or four times the size of ordinary ones, in w'hieh two or three
nuclei are visible. Instead of multinuclear bodies, a number of medullary
nucleated elements may fill a large lacuna. Numerous cement-corpuscles
send broad and branching offshoots through the basis-substance in a vertical
or oblique direction to the lamellte, and not infrequently a direct union is
established between two or three cement-corpuscles by means of such large
offshoots (see Fig. 262).

In some teeth, broad, spindle-shaped spaces pierce the cementmii in a
radiated direction, all of which contain bioplasson with delicate offshoots
directed toward the net-work in the basis-substance. Nay, sometimes medul-
lary spaces traverse the lamellse in different directions, which, besides a vary-
ing number of medullary elements, contain capillary blood-vessels, evidently
in connection with the capillaries of the pericementum. These formations
may be considered as remnants of the em1)ryonic condition of the cementum,
and are never present in large numbers. All plastids within the cementum,
though gi'eatly varj'ing in shape, agi-ee in being connected with each other by
the delicate net-work which pierces the basis-substance.

At the periphery of the cementum, on the line of the connection with the
pericementum, the net-work of the bioplasson is usually very broad, and the
fields of the basis-substance show a prevailing globular appearance. Also,
numerous spindle-shaped plastids are seen in connection with the cementum
in an oblique arrangement, forming the transition into the structure of the
pericementum. Between the calcified cementum and the striated connective
tissue of the pericementum there often exists a narrow zone, occupied by
closely packed spindle-shaped bodies only.

The connection between dentine and cementum is established either by a
gi-adual change of one tissue into the other, without a distinct line of demar-
cation, or there exists a boundary formed by a more or less marked wavy line,
presenting irregular, bay-like excavations. Lastly, it occurs that between the
bay-like excavations and the dentine there is interposed a stratum of the
structure of cementum, with a gradual change of the tissue of the former into
that of the latter. ,

618

THE TEETH.

Where a ^adiuil change takes place, the dentinal canaliculi show irregular,
mainly spindle-shaped, enlargements, which stand in the direction of the den-
tinal canaliculi themselves, or run obliquely through the basis-substance of
the cementum. The distal end of such a spindle is, as a rule, in connection
with a regular lacuna of the cementum, or with an analogous formation of a
neighboring dental canaliculus. Many of the latter simply pass into the light,
delicate net-work characteristic of the basis-substance of cementum. The
dentinal fiber is in direct union with the bioplasson, which fills the spindle-
shaped spaces, or it is lost to sight upon entering the net-work of the basis-
substance of the cementum. (See Fig. 264.)

Pig. 2G4. — Transition of 1)p:ntine into Cementum,

WITHOUT A INIaRKED BOUNDARY.

C, branching cement-corpuscle ; P, spindle-shaped comeiit-cori'nscle, botli in direct con-
nection with dentinal libers, F, which bifurcate within tlie canaliciUi of tlie dentine, D.
Magnified 1200 diameters.

Where a boundary with bay-like excavations is present between dentine
and cementum, spindle-shaped enlargements of the dentinal canaliculi may be
seen, much smaller than in the former instance. The majority of the dentinal
canaliculi, however, reach the boundary of the cementum after repeated
bifurcations, by which both the calibers of the canaliculi and their central
fibers are gradually diminished in size. A connection of the dentinal fibers
with the coarser offshoots of the cement-corpuscles is often observed. The
light net-work of the basis-substance of the dentine always passes into that of
the cementum. Not very rarely, also, on the bottom of a bay-like excavation,
partly nucleated plastids are present, into which the dentinal fibers inosculate.
The connection between these and the coarser offshoots of the cement-cor-

THE TKKTll.

619

puscles under these circumstances is established by such intervening bodies.
(See Fig. 205.)

For the designation of the biojjlasson formations between the dentine and
enamel, and dentine and cenientuni. I adopt tlie term "interzonal layer," as
tii'st proposed by Dr. W. H. Atkinson.

Seek of Tooth. There are certain peculiarities about the minute anatomy
of the neck of the human tooth, which, so far as I can judge from the litera-
ture within my reach, have not been heretofore mentioned.

John Tomes, in describing the distribution of the dentinal tubes, says:
" Near the neck they stop short of the eementum." This assertion
is in accordance with my own observations. In the gi'eat majority of
teeth neither the eanaliculi nor their contents, the dentinal fibers, reach

1

•c?

Fig. 265. — Traxm ri«>.\ i,v Dextixe ixto Cement, with ax Ixter-
MEDiATE Layer op Cemekt-structure.

Z>, dentine; F, bilureating tlentine-fibers, in union with elongated cement-corpuscles, C;
these are imbedded in a basis-substance blendinir witli that of dentine. The regular cementnm
is characteiized bj- branching corimscles, C*. Maguitied 1200 diameters.

that part of the eementum which surrounds the neck. Near the periphery
of the dentine biftircations of the eanaliculi — and consequently also of
their tenants, the dentinal fibers — take place, some of the finest terminations
of which run to the boundary between the dentine and eementum. As a rule,
the finest terminations of these fibers are lost to sight in a net-work somewhat
coarser than that of the basis-substance of ordinary dentine. Sometimes the

620

THE TEETH.

dentinal canaliculi, when approaching the periphery, become slightly dilated,
so as to produce slender, pear-shaped cavities, in accordance with which the
terminating dentinal fibers exhibit slight enlargements.

The boundary between dentine and cementum presents a wavy line,
traversed by delicate threads, or occupied by spindle-shaped bioplasson for-
mations, all of which are in union with direct or indirect elongations of the
dentinal fibers.

The cementum around the neck forms a narrow layer, which is cut off
obliquely at the place of junction with the enamel. Both the cementum and
enamel in this situation — being of the same width — are separated by a
boundary which runs from the outer periphery obliquely downward to the
dentine. This relation I found in the majority of teeth, and it is only
exceptionally that I have met with cementum overlapping the enamel. The
cementum on the neck is built up by delicate prisms, or spindles, arranged

I>F

DP

Fig. 2G6.— Anomalous Formation of Cementum ox the
Neck op a Human Tooth.

D, dentine ; N, cementum on neck of tootli, with spindle-sliapea or prismatic fields of
basis-substance ; DP, depression in tlie cementum of the neck, filled with elements of peri-
cementum, P, surrounded upward by a zone of rejrularlj' developeil cementum, Cc. Magnified
1200 diameters.

vertically to the surface of the dentine. The prisms represent the fields of
the basis-substance, and are separated from each other by light rims, holding
beaded fibers, or traversed by delicate vertical threads. In transverse sec-
tions, when the prisms are cut obliquely, they exhibit irregular, opaque fields,
separated from each other by light rims.

The cementum on the neck of the tooth is devoid of lamellse and lacunae,
which appear deeper below, together with all the characteristic features of
the fully developed structure of the cementum. The lamella} become the

77/ A' TKKTII.

621

ER

E F

Fig

267.— Longitudinal Sec-
tion OF Enamel.

ER, enanicl-rods, traverstMl by pre-
vailiug vertical spaces; EF, euamel-
fibers, braiicliiiiK and partly unitiuK
by delicate otlshoots. MaKiiilii'd 1200
diameteis.

more distiiu't, and the lacuna', with their contents (the cement-corpuscles),
the more numerous, the broader the diameter of the layer of the cementum.

The outer surface of the cementum is covered on its upper part with a
narrow layer of connective tissue and with epithelial elements, in close
resemblance with those of Nasmyth's layer of the enamel. This layer turns
over into the epithelial coat of the fjum.

I have met once with strikinj^ formations on the neck of a tooth. The
ordimirv cement of the neck is interrupted by ^n'ooves or yiits containing the
elements of pericementimi. The inner per-
iphery of the pit is coN'ered with a well-
developed, evidently isolated, formation
of cementum. The island of the cemen-
tum is broadest above the bottom of the
pit, and slopes down along the walls of the
pit until it is lost within the layer of the
cementum of the neck. (See Fig. 266.)

Euamel. Up to this time the impression
of most examiners has been that the
enamel is built up by bundles of rods or
prisms, crossing each other, and traversed
by faint vertical lines, which give each of
them the appearance of a column sub-
divided into small squares. The enamel-
rods doubtless exist, and are wa\'y close

to the dentine, and straight on the periphery and the main mass of the enamel.
They may be considered as columns of a calcified substance, between which
minute spaces are left, analogous to the cement-substance of epithelial for-
mations.

In longitudinal sections we see delicate beaded fibers, which occupy the
central portion of the interstices between the enamel-rods. These fibers I
propose to term the ''enamel-fibers." From such a fiber arise very minute
conical fibrilla?, which traverse the rims between the fiber and the neighbor-
ing outlines of the rods, and fade away from the moment they enter the
latter. The columns of the basis-substauee themselves are pierced by deli-
cate canaliculi, running in an almost vertical direction through the enamel-
rods, regularly enough to give the appearance of squares, although these are
much smaller than usually represented. In the middle of a minute square
light canals are seen, not infrequently running parallel with the outlines of
the enamel-rod. The square fields thus produced by the rectangular crossing
of light channels look, imder the power of 1200 diameters, finely granular.
In specimens not fully decalcified it is impossible to decide whether there is a
light net-work within the enamel prisms analogous to that in the basis-
substance of the dentine and cementum, or whether the granidar appearance
is merely due to the depositions of lime-salts. CSee Fig. 267.)

Cross-sections of the enamel, which we obtain also in longitudinal sections
of the tooth, on account of the different directions of the bundles of the
enamel-rods, plainly exhibit the irregular polyhedral fields of the enamel-
rods. The light interstices between the polyhedral fields contain in many
instances delicate beaded fibers surrounding the polyhedral fields of the
enamel-rods. The fibers, if cut transversely, have the appearance of dots,
and connect with each other directly or by means of intervening delicate

622 THE TEETH.

threads. Extremely fine tliovns traverse in a vertical direction the light
space between two neighborijig enamel-rods, even where a fiber is not visible.
(See Fig. 2GS.)

The rods of the enamel, on an average, are lialf the diameter of the col-
umns of the basis-substance in dentine ; therefore four columns of the former
will correspond to two of the latter. Sometimes in the cross-section of an
enamel-rod I met with roundish formations occupying the center of the rod,
one or two in number, which, owing to a denser gi-anulation and a surround-
ing shell, have the appearance of nuclei. The enamel-fibers run a very
straight course toward the siu'face, and are here usually a trifle thicker than
near the boundary of the dentine.

The outermost surface of the enamel is covered by flat epithelia (Nas-
myth's laembrane), which, in the transverse section, have the appearance of

flat spindles ; not infrequently there also
. i,„ occurs a stratified epithelium on the surface
of the tooth. The enamel-fibers are in con-
nection with these epithelial bodies, which,
if detached, show delicate offshoots adhering
at regular intervals — the broken enamel-
fibers. Sometimes the surface of the enamel
-c/ -c 3*^ ,<-« fn x.m'ssjk^vy jg coated by a thin, uniform layer, with regu-

larly scattered nuclei.

At the place of junction of the enamel

Fig. 268.— Cross-Section of with the dentine a direct connection is often

Enamel. seen between the enamel and dentine fibers.

£i?,r.,ds of enamel, partly exl.ibit- ^he latter, through repeated bifurcations,

ing formations like nuclei; the light being closely brought together, continue

interstices between tlie roils traversed their course into the enamel-fibers without

by delicate beaded libers, EF, or bv ■ ■ j. j.- rm ,t .„,+;„ „* ii,„ ^i „

^. , ., -. .„' '„„ ,. any interruption. The direction ot the fibers

vertical thorns. Magnified 2000 di- * ^

ameters. of the two tissues, however, is almost never

identical, inasmuch as the enamel-rods, and
consequently the enamel-fibers, as a rule, owing to their wavy course in this
situation, are obliquely intercepted upon the dentine.

We can very often trace dentinal fibers up into the enamel in a varying
distance, without a distinct union between the enamel and dentine-fibers, as
the former do not reach the surface of the dentine, but terminate above its
level at different heights, while the zone close above this is occupied by a
delicate, iiTegular net-work analogous to that of the dentine. (See Fig 269.)

In many places the dentinal canaliculi upon entering the enamel suddenly
become enlarged, and form more or less distinctly spindle-shaped cavities of
greatly varying diameters, analogous to the spindle-shaped enlargements at
the boundary of the cementum. These enlargements run either in the main
direction of the dentinal canaliculi or deviate obliquely. They invariably con-
tain bioplasson bodies, wliich plainly show the reticular structure, and some-
times contain one or more compact clusters to be considered as nuclei. The
spindle-shaped bodies, on their proximate ends, are in direct connection with
the terminations of the dentinal fibers which have arisen from their repeated
bifurcations, while on the distal end they may show delicate fibers — viz. :
enamel-fibers — or delicate conical thorns traversing the light space between
the sm'face of the bioplasson body and the wall of the cavity. These thorns
are lost to sight on passing into the net-work at the bottom of the enamel.

THE TKKTU. 623

III some places, especially on tlie cusps, the spiinllr-sliai)e(l eiilarf^ements of
the (leutine-fibers are quite numerous, and of an almost uniform size and
direction, formiufj regular rows of sjjindles within the enamel. In the teeth
of younger individuals tlie spindle-shaped enlar}<ements are comparatively
larjyer and more regidar than in the teeth of old people.

The boundary line between the dentine and enamel is either straight or
slightly wavy, and with more or less deep, bay-like excavations, analogous to
those on the boundary between dentine and cementum. The concavities of
the bays are directed toward the dentine. In this interzonal layer at the bot-
tom of the bays we meet with fibers occupying the curved spaces between
dentine and enamel, or we see, in a correspondingly bent direction, bioplasson
bodies directly connected with the dentinal fibers dowTiward, and with the
enamel fibers upward. (See Fig. L>70.) In specimens stained with chloride of

/; E

E F-

FiCi. 201). — UXIUX UF DeXTIXE with ENAilEL.

/), dentine; ^.enamel; OF, dentinal fibers, beln;? in union with large bioplasson bodies,
P, or directlj- running into enamel-fibers, KF ; the latter often are lost in the delicate, irrega-
lar net-work ou tlie bottom of the enamel. Magnifieil 1200 diameters.

gold the dentine is always much deeper in color than the enamel, hence the
relations described are very plainly marked on such specimens.

Results. The details described make it evident that we shall have to mod-
ify considerably the views heretofore maintained on the structure of the
teeth. Since we have known the structure of "protoplasm," and that of
basis-substance of connective tissue, by the researches of C. Heitzmann, we
are accustomed to look for the distribution of the living matter not only in
the plastids (the formerly so-called cells), but also in the basis-substance,
which formerly was thought to be devoid of life.

The structure of the tooth closely resembles that of bone. We know that
the basis-substance of bone is traversed everywhere by a net-work of living

624

THE TEETH.

matter, in the shape of beaded fibers, where they form larger offshoots of the
plastids. Similar features are also present in the tissues of the tooth.

(1) The dentinal canaUcuU are excavatious in the baf>is-substance of the den-
tine, each containinf/ in its center a fiber of living matter. Besides the dentinal
canaliculi, there exists an extremely delicate net-work within the basia-snbutance
of the dentine, into which innumerable offshootn of the dentinal fibers pass.
Although tee cannot trace the living matter throughout the whole net-work in
the basis-substance, we are justified in assuming that not only the dentinal canal-
iculi, but the whole basis-substance of the dentine, is also pierced by a delicate

net-work of living matter. The
living matter of the dentine is in
direct union with that of the bio-
plasson bodies of the pulp, of the
cementum, and of the enamel.

(2) The cementum, as well as
^J" ordinary bone, is provided with la-
cunas and canaliculi. The lacunce
contain nucleated plastids, and the
canaliculi hold offshoots of the liv-
ing matter of the plastids. The
whole basis-substance of the cemen-
tum is traversed by a delicate net-
work, which in all probability con-
tains living matter, though this is
traceable only in its thorn-like pro-
jections from the periphery of the
plastids and their larger offshoots.
The living matter of the cementum
is uninterruptedly connected with
that of the pericementum, and con-
tinuous with the living matter of
the dentine, either through inter-
vening hioplasson bodies in the in-
terzonal layer, or directly with the
dentinal fibers.

(3) The cementum covering the
neck of the tooth is devoid of lamclke and plastids. It is built up by directly
ossified osteoblasts of the pericementum, presenting their prismatic shapes, and
everywhere traversed by a net-work of living matter. This is in connection with
the pericementum, and with the dentine mainly through the intervening net-work
in the basis-substance of the latter.

(4) The enamel is traversed by fibers of living matter located in the inter-
stices between the enamel-rods. The fibers are connected icith each other by delicate
fibrillee, jtiercing the enamel-rods in a vertical direction. The enamel-fibers send
conical thorns toward the enamel-rods, and such thorns are visible in all interstices
between the enamel-rods. The enamel fibers are continuous on the outer surface
with the covering layer of fiat epitltelia, and on the inner surface with the dentinal
fibers. The latter connection is either direct or indirect through a net-work of living
matter, or through intervening hioplasson bodies in the interzonal layer.

History. It is not my intention to traverse the entire history of micro-
scopical studies regarding the struetui-e of teeth. I propose to quote only

DT

Fig.

270. — Union of
Enamel.

Dentine with

/>, dentine; -E, enamel; P, bioplasson formations
at the bounilaiy between both tissues, in union
■with enamel-tibers, HF, and witli dentine-fibers,
DF. Magnified 1'2()0 diameters.

Tin-: 1 1-: Kill. 625

from ri'jiresi'iitative wntrrs on odoiitoloj^y, in onler to show liow the present
theories on this siil>jeet Inive V)een ffradually developed.

I qnote from John Hunter*: "Enamel has no marks of being vascular,
arid of having a cireulation of fluids ; it takes no tinge from feeding with
madder, even in the youngest animals. This looks as if the enamel were
the earth more fully depurated, or strained off from the common juices
in such a manner as not to allow the gross particles of madder to pass.
The other substance of which a tooth is composed is bony, but much harder
than the most compact part of bones in general."

Joseph Fox t says : " The enamel, wlien broken, appears to be composed of
a great numV)er of small fibers, all of which are so arranged as to pass in a
direction from the center to the circumference of the tooth, or to form a sort
of radii round the body of the tooth. This is the crystallized form it acquires
some time after its deposit. The structure of the teeth is similar to that of
any other bone, and differs only in having a covering, which is called enamel,
for the exposed surface, and in the bony part being more dense."

Thomas BellJ maintains: " There are two distinct substances which enter
into the composition of the teeth, essentially differing from each other in
structure as well as in chemical composition ; the one being organized, the
other crystalline. The first, of which the mass of the tooth consists, is true
bone ; the second, from its appearance, is called enamel."

Alexander Nasmyth $ on cementum says : " The cortical substance is always
found on the peripheral part of the tooth, forming a layer of investment around
it, and lying in close apposition with the enamel or ivory. The cortical sub-
stance has no organic connection with the enamel or ivory against which it
lies, and, being softer than both, is easily detached by means of a knife. In its
intimate structure it presents the characteristic corpuscles and canals of bone,
the latter being filled with ossific matter, but otherwise resembling Haversian
canals. In structiu'e, cnatinl is composed of cells which are arranged in regular
rows, forming composite fibers placed at nearly right angles to the surface of
the ivory, the original nuclei of the cells not being persistent. Dentine. It
has long been known that the teeth are composed of two essential chemical
constituents, namely, earthy salts and animal matter. From Dr. Thomson's
analysis it appears that the quantity of animal matter is very considerable,
and it is evident that it is contained chiefly in the fibers, or, as they have
been termed, the tubes of the ivory. It was quite evident to me, from the
examination of preparations, that the so-called tube was in reality a solid
fiber, composed of a series of little masses succeeding each other in a lineao*
direction, like so many beads collected on a string."

Richard Owen, || in describing the structure of dentine, says : " The
compartments of the basal substance, which I have called ' ealeigerous,' or
' dentinal cells,' and which contain the hardening salts in their densest
state, are sub-circular or sub-hexagonal. The ealeigerous and nutrient tubes,
varying fi-om l-10,000th to 1-20, 000th of an inch in diameter, are placed
with intervals equal to from two to six of their own diameters. They are
nearly parallel to one another, both in their general course and curvatures,

' "The Natural History of the Hiiman Teeth," etc., 1778.

t "The Natural History ami Diseases of the Hiiiiian Teetli," 1814.

t " Anatomy, Physiolojry, ami Diseases of the Teeth," 1831.

i " Researches on the Development, .Structure, and Diseases of the Teeth," 1849.

II " Oilontography," 1840-45 (vol. i., pp. 302, 303, and 304).

40

626 THE TEETH.

but as the outer surface of the tooth exceeds the inner one in extent, the
tubes slightly diverge in their course and divide, decreasing in diameter to
their peripheral extremities, and rapidly so near their terniinatioiis, where
they become irregularly flexuous and often interlaced. The dichotomizing
ealeigerous tubes send off from their sides much more minute branches, which
quickly divide and subdivide in the interspaces of the trunks and penetrate
the dentinal cells. The cciiioit, which, with the dentine, is present in all teeth
of mammalian animals, is cliaracterized, except where it forms an extremely
thin layer, by the radiated ealeigerous cells, usually arraiiged in lines or
layers parallel with the surface of the cemental coat, and with each other.
The enantcl consists of more or less curved or wavy prismatic fibers, averaging
about l-4000th of an inch in diameter, and transversely striated."

John Tomes * says of enamel : " The organic matter said not to belong to
the class of gelatinous tissues, but to be closely similar to epithelium in
its chemical relations, is stated not to exist between, but in the substance
of the prisms (Hoppe-Seyler). The enamel- is made up of parallel fibers,
which lie in close contact with one another, no intervening substance being
demonstrable." On dentine : " In the crown of the tooth the dentinal tubes
terminate by forming loops, or become too minute to be traced, or pass into
the enamel and become lost. In teeth the dentine of which is imperfectly
developed, the terminal branches are lost among, or end in, the minute cavi-
ties which abound iu the layer at or near the peripheral surface of the dentine.
Near the neck they stoj) short of the cementum, liut toward the end of the
root they not uncommonly pass into the cementum and connect themselves
with the lacimse. By the extension of the dentinal tubes into the enamel and
into the cementum, a connection is formed more intimate than mere superposi-
tion and adhesion of the one to the other would have established. In prepara-
tions in which we are fortunate enough to retain a portion of the pulp with
the dentine, it may readily be seen that the soft fibrils are processes of the
cells known as 'odontoblasts,' which constitute the peculiar layer called the
membrana eboris. It is absolutely certain that no structures other than
nerves have the power of conducting sentient imjiressions, and hence it is not
quite necessary to assume that the dentinal fibers are actual nerves before
allowing them the power of communicating sensation. The greater degree
of sensitiveness observable in the dentine immediately below the enamel —
that is, at the point of ultimate distribution of the dentinal tubes, and conse-
quently of their contents — may be fully accounted for on the supposition
that the latter are organs of sensation, the highest sensibility of which is
confined to their branches." On cementum : "The canaliculi of neighboring
lacunas anastomose freely with each other, and establish a net-work of com-
munication throughout the whole body of the cementum, and occasionally
Vjecome connected with the terminal branches of the dentinal tubuli. It is
to the description of primary bone that the cementum of the teeth is most
closely allied, and from that it is difficult to point out any distinguishing
structural character."

Charles S. Tomes t maintains of enamel: "In perfectly healthy human
enamel the fibrillar arrangement is not so verj^ strongly marked; the fibers
are solid, are in absolute contact with one another, and have no demonstrable
intervening or uniting substance, or else inter-spaces would be left, which is

* "System of Dental Surjiery," 1873. t " Manual of Dfutal Anatomy," 187G.

THE ri'.i'/ni. 627

not found to be the case. In man, dcntinul tubes may occasionally be seen to
enter the enamel, passing across the boundary between the two tissues, and
pursnin}; tiieir course witiiout ])ein{^ lost in irre<;ular cavities." On dnttbie :
'■ lOacdi dentiiuil tube runs outward in a direction f^enerally perpeiulicular to
the surface toward the peripliery of the dentine, wiiich, liowever, it does not
reach, as it becomes suniller, and breaks u]> into l)ranches at a little distance
beneath the surface of th(> dentine. The tubes have definite walls, and are
not simple channels in the matrix. These walls are composed of something
singularly indestructible. Indeed, the walls of the dentinal tulies are so
indestructible that they may be demonstrated in fossil teeth, in teeth boiled
in caustic alkalies, or in teeth wliieh have been allowed to putrefy. Similarly
indestructible tissues are, however, to be met with suiTOunding the Haversian
canals and the lacunae of boue. Each canal is occupied by a soft fibril, which
is continuous with the odontoblast cells upon the surface of the pulp ; the
existence of these soft fibers was first demonstrated by my father. In the
dentine, then, we have (1) a matrix permeated by tubes; (2) special walls of
these tubes, or dentinal sheaths ; and (3) soft fibrils contained in these tubes,
or dentinal fibers. . . . Owing to their breaking up into minute branches,
some of the tubes become lost as they approach the surface of the dentine,
and apparently end in fine-pointed extremities. Some terminate by anasto-
mosing mth terminal branches of others, forming loops near to the surface of
the dentine ; others terminate far beneath the surface in a similar way.
Some tubes pass into the small, interglobular spaces which constitute the
' granular layer ' described by my father, while others again pass out alto-
gether beyond the boundary of the dentine and anastomose with the canali-
culi of the lacuna; of the cementum. The enamel also may be penetrated liy
the dentinal tubes, though this, when occurring in the human subject, must
be regarded as exceptional and almost pathological in its nature. Of the real
nature of the dentinal fibrils some doubts are entertained, . . . Nerves, in
the ordinary sense of the word, they are not, and have never been supposed
to be. . . . The cemcntmn, in my opinion, is present in a rudimentary condi-
tion upon the teeth of man, etc., as Nasmyth's membrane. It consists of a
calcified matrix or basal substance, to a slight extent laminated, and lacuna?.
Many of the lacuna? in cementum are connected, by means of their canaliculi,
with the terminations in the dentinal tubes ; they, by the same means, fi'eely
intercommunicate with one another. In the fresh condition it appears prob-
able that the lacuna? are filled up by soft matrix."

Carl Wedl * says : "Isolation of the enamel-fibers may easily be effected by
means of dilute hydrochloric acid. The fibers, becoming swollen and varicose,
present on the depressed portions an apparent transverse striation, and
between the opi)osing contiguous portions narrow, fissure-like intervals re-
main, which have given rise to the view entertained by some investigators
that canals are found in the enamel. The junction of the enamel with the
dentine is effected by a transparent, irregular, wavy boundary layer, which in
some parts is encroached upon by separate dentinal canals, and in othei-s by
elongated, cleft-like cavities, of irregular shapes and different dimensions.
Into these cavities, which are mostly filled with opaque, amorphous, calcare-
ous masses, one or another of the dentinal canals frequently enters. The
cement has an organic connection with the periosteum of the root or root-
membrane. Sometimes the canaliculi radiate from the bone-corpuscles in

* " Piitliolofry of the Teetli," 1872.

628 THE TEETH.

parallel rows, and extend a considerable distance without forming a net-work.
The dentine and cement are connected together by means of a layer composed
of an agglomeration of transparent globules, of varying degrees of thick-
ness. The spaces intervening between the latter (interglobular spaces)
are irregularly notched, and frequently in very close proximity to one
another ; they are filled with an opaque, granular, calcareous substance, and
very often are in direct connection on one side with dentinal canals, and on
the other side with the bone-corpuscles of the cement. Sometimes this inter-
mediate layer is verj' finely granular, and the spaces between the grains are
exceedingly small. The cement proper commences outsiile of this layer, and
its canaliculi rarely come into direct connection with the dentinal canals."

From W. Waldeyer ' I quote : " The chief components of dentins are a very
firm matrix, analogous to compact bony tissue, and extremely fine, frequently
branched, fibers, — the dentinal fibers of Tomes and Kolliker, — which occupy
fine canals, the dentinal canals traversing the matrix. The dentinal fibers
are enormously elongated ftrocesses of the so-called dentinal cells, or cells of
the dentinal pulp (odontoblasts). The dentinal fibers constitute the soft
parts of the dentine. They do not lie in direct contact with the hard matrix,
but are invested by a sheath, — the dentinal sheath of E. Neumann, — which is
intimately connected with the matrix. As a general rule, each tube extends
from the pulp-ca\ity to the enamel or cement, gi\dng off, in its course,
numerous delicate, transverse branches. By means of these transverse
branches both the tubes and their contents — the dentinal fibers — anasto-
mose with each other. In regard to the mode of peripheric termination
of the dentinal tubuli, no positive conclusion can be drawn. It is not easy to
decide whether the fibers are present in the finest peripheric ramifications of
the tubules. A direct passage of the dentinal tubuli into the enamel does not
occur." On enamel : " It consists of rather elongated prisms, about three to
five mm. long, which are called enamel-fibers, or enamel-prisms. The dark,
transverse striae and slight varicosities, which, especially after the addition of
verj' dilute hydrochloric acid, occur at regular distances from one another in
the isolated prisms of enamel, are very remarkable. If the treatment with
hydrochloric acid be continued for some time longer, the fibers split, in the
direction of the clear transverse lines, into small cubic fragments of nearly
equal size, three to four mm. The enamel fibers lie in close contact with each,
other, without any demonstrable intervening substance. The cuticula (per-
sistent capsule of Xasmyth) forms an extremely resistent investment, not
more than one-half mm. \i\ thickness, covering the external portion of the
teeth, and disappearing wholly when they are mature." On cementiim : "The
cement is a true bony structure essentially belonging to the periosteum of the
alveolus, and in man and many vertebrates forms a thin investment of the
fangs of the teeth. The lacunae are for the most part large. When the
cement is extremely thin, however, they may be entirely absent, and it then
presents on section a perfectly homogeneous and vitreous appearance. A
similarly very hard lamella, destitute of lacunae, occurs also in the outermost
portion of the thick layers of cement."

E. Magitot t says : " The dentine is bounded throughout its whole external
surface by a continuous layer of dark granulations, very numerous and of
various form. This granular layer, subjacent to the enamel and cement, was
taken by Retzius and J. Miiller for a mass of bony corpuscles, in which ter-

' Strieker's "Manual of Histology," 1872. t " Treatise on Dental Caries," 1878.

THK TEETH. G29

minatod the canaliculcs. But an attentive examination shows that, altlioiifjh
tilt" f^ranulafions are continuous witli the terminal extremities of the (?aiial-
ieult's, we eauuot compare them to osseous coi-puscles, V)ut that they siiould
rather he ret^anied as minute pits sunk in the tliickness of the ivory, at its
exterior limit, to aid the communications between the tubules which permeate
this tissue. . . . During lit'c^ the dentinal eanalicules inclose a transi)arent,
colorless fluid, containinj;, according to Hannover, calcareous matter in solu-
tion. . . . For a long time there has been attributed to the ivory a sensi-
bility of its own — an opinion still held by many, even in the admitted
absence of nerve-V)ranches, and supported by the fact that the teeth vividly
perceive the impressions of temperature, of acids, etc., and distinguish the
physical qualities of bodies submitted to their contact, such as gi-ains of sand
and hairs. This tactile sensibility, in fact, does not belong to the ivory, and
must be attributed to the extreme facility with which this substance receives
the least vibrations, the slightest disturbances which are given to it by
external influences, and transmits them to the pulp, whose tissue, extremely
rich in nerves, fills exactly its solid shell, and thus perceives the smallest
impressions communicated to it." Of the enamel 'he asserts: "The layer of
enamel suiTounding the crown is composed of an infinite number of rods,
prismatic by reciprocal pressure, whose length is just equal to the thickness
of the tissue at the corresponding point, and intimately united without the
interposition of any other substance."

Dentine and Enamel of Deciduous Teeth. By Frank Abbott, M. D.*

While engaged in the study of the process of dissolution of temporary
teeth, I availed myself of the method of examination of enamel as first
described by Biidecker. Specimens of deciduous teeth, if prepared in this
manner, exhibit, as the most striking feature, a considerably smaller amount
of basis-substance than adidt teeth. As a consequence, the dentinal canal-
ieuli are much wider, and the dentinal fibers larger ; thus, the possibility of
seeing the minutest relations between dentinal fibers and basis-substance is
greatly facilitated.

I can add nothing to what Bodecker has described in minutest details in
reference to the structure of dentine. I could easily see the dentinal fibers
(which, upon being stained with carmine, assume a dark red color) running
through the canaliculi up to their bifui'cations, close to the enamel. I could
trace the lateral conical offshoots of the dentinal fibers to the point where
they enter the basis-substance of the dentine. That the basis-substance holds
a delicate reticulum of living matter I am perfectly satisfied, and I base my
opinion upon my researches on caries of the teeth.

As to enamel, I have never seen the minute relations marked so plainly in
permanent as I find them in the temporary teeth. Here the enamel-rods are
narrower, and the interstices between them wider, than in permanent or adult
teeth. A power of 500 diameters of the microscope is sufficient to show
plainly relations visible in permanent teeth with very much higher powers
only. As a striking feature in deciduous teeth, I often found a direct connec-
tion of the fibers of the dentine with those of the enamel. Thus, the width of
an enamel-rod is in full correspondence with the width of the fields of basis-

* Abstract from the aathor's paper, " The Minute Anatomj' of Dentine and Enamel." The
Dental Cosmos, Philadelphia, 1880.

030 THE TEETH.

siibstaiico of the dentino, after the bifuvcation of the dentinal tillers, near the
boundaiy between dentine and enamel.

In preparing specimens, on several portions of the crown it happened that
a larger portion of the enamel was ground away than was intended — so much
so that only shreds of enamel in connection with the dentine were left. On
one of these places delicate beaded fibers were seen isolated on their upper
ends, while their lower ends could be traced into interstices between the
enamel-rods, and in connection -with the ends of the dentinal fibers. No doubt
here the mechanical injury done to the enamel has luckily led to a tearing out
of a few enamel-fibers, which accident plaiidy illustrates their presence.

That enamel is not a crystal, but a tissue, — alive so long as the pulp of
the tooth is alive, — no one, I think, will doubt who has studied caries and
seen the pigmentation of enamel and its reaction during that process.

Secondary Dentine. By C. F. W. Bodecker, D. D. S., M. D. S.*

It is generally acknowledged that the main portion of a tooth is composed
of dentine, which, on the crown, is covered by enamel. The latter is thickest
aroiind the cusps, and becomes thinner the nearer to the neck. On the root
the dentine is covered by cementum, which is thinnest about the neck, and
thickest on the apex of the root.

Exceptionally the relations between the three hard tissues of a tooth may
be found to deviate considerably from the general rule, whereby an anoma-
lous, though not strictly pathological, formation is produced. I extracted the
canine teeth from the upper jaw of a lady forty years of age, one of which I
split to obtain the pulp ; the other was gi-ound thin immediately after its
extraction, for the purpose of studying enamel. The results were as follows :

The crown was built up by dentine terminating in the ordinary pointed
way, and suiTounded by a well-developed cap of enamel. A marked brown
discoloration in the usual fan-like arrangement was noticeable in the enamel,
mainly in the immediate neighborhood of the dentine, but without any decay.
The dentine, beginning at the neck and extending down into the root, was
divided into a broad inner portion, occup^-lng four-fifths of the root, and a
narrow outer portion all around, corresponding in its thickness to that of the
cementum of normal teeth. The boundary between these two layers was
everywhere well defined by a scalloped line, the concavities of which look
outward. In some places several such scalloped marks ran perfectly parallel,
close to each other. The boundary line, however, was traversed by the den-
tinal canaliculi and their tenants without change of direction. The outermost
portion of the dentine of the root was surrounded by cementum, not thicker
than is seen on the necks of teeth of normal development. The cementum
was slightly thicker on one side of the apex of the root, exhibiting there a
scanty number of cement-corpuscles, which on all other portions were want-
ing. The boundary between dentine and cementum was sharply defined.
The former bore the characteristics of dentine in the vicinity of the neck, as
the canaliculi stopped short of its surface and were replaced by a coarsely
granular basis-substance. (See Fig. 271.)

Nearest to the pulp-chamber there is a zone, with scanty and irregular
dentinal canaliculi — formations which we are accustomed to call " secondary
dentine." Next to this is a broader layer of dentine, in which the dentinal can-
Abstract of tlie author's essaj'. The Dental Cosmos, Philadelphia, 1879.

77//'.' ri:i<rii.

631

n-

alic'uli run in ImiKile.s aiwl in a slif,'htly irrof^iilar, wavy eoursp. Tlion we sfe a
hroad portion of fully (Icvclopcd (U'litinc, tho canalifuli of which do not reach
the ceniontuni, but beneath the latter are rei)lace<l by a coarsely f^ratiular net-
work. On the outer surface appears the relatively narrow layer of eementura
of a laniellated structure. Higher mafjnifyiuf? powers of tiie microscope give
an insight into the minute structure of the dentine and cementum. In the
layerof dentine the terminations

of the dentinal fibers are seen PC iH~"'~^""^~ ' -^-
bifurcated, and leading toward |lJt\!„''. 'y\

the light reticulum, in wliich we ■|^^j:„,<-,Lit^^^
assume the presence of living --*J---iii-^-^'-2ii2i^ \^

matter. The lamellated cemen-
tum is provided witli a number i
of curved spindles, which in their fc/
general direction correspond to f-' \
the course of the dentinal fibers, ;j; '
while the basis-substance be-
tween the spindles appears finely
granular. On that portion of the
cementum of the root which is
pro%'ided with cement corpus-
cles a distinct boundary be-
tween dentine and cementum
is wanting. (See Fig. 272.) In
this tooth, therefore, the cement-
layer is replaced by a regularly
developed layer of dentine, the
former being very thin, and, with
the exception of a limited por-
tion, devoid of cement-corpus-
cles.

In the crown a conical por-
tion, the blunt lower end of
which binds the pulp-cavity,
exhibits a structure which
doubtless has all the essential
properties of dentine, though in
a considerably more irregular
aiTangement than ordinary den-
tine. The regular dentine ter-
minates almost abruptly all
around the cone of the irregiilar
dentine. On the apex of the

latter, large, irregularly shaped, branching spaces are visible, all of which
contain partly nucleated bioplasson formations. (See Fig. 273.) The spaces,
and respectively their tenants, are mainly pear-shaped, with their bases
directed toward the regular dentine, with their elongations passing into the
iiTCgular dentine. From the broad bases arise numerous conical offshoots,
by means of which a direct communication is established with the dentinal
fibers of the regular dentine, while other offshoots inosculate with analogous
formations on the apex, thus producing a coaise net- work. From the pointed

LB

Fig. 271. — Root of an Anomalous
Canine Tooth.

i>, piimaiy dentine; LD, socontlaiy dentine, com-
posed of two zones ; P, pulp ; C, cementum ; PC,
lierieenieutum. Magnified 300 diameters.

632

THE TEETH.

lower ends of the pear-shaped spaces wavy canaliculi originate, which freely
anastomose with each other, and traverse the whole mass of the central por-
tion of the crown in a prevailing radiate arrangement. Their number is more
scanty than in the regular dentine, so much so that relatively large territories
of the basis-substance are altogether devoid of canaliculi. The latter hold
delicate beaded fibers of living matter, as well as the canaliculi of normal
dentine, with the exception that on the average the fibers of normal dentme
are finer than those of the secondary formation. Some of these fibers are pro-
vided with lateral conical offshoots, directed toward the basis-substance,
which itself shows a delicate reticular structure,
of essentially the same character as I have seen
in regular dentine. (See Fig. 273.)

The middle portion of the pulp-cavity is
bounded by a narrow zone of dentine, which is
possessed of canaliculi in a smaller number than
the main mass of dentine. This zone, besides,
is characterized by a deep carmine stain, while
the regular dentine remained almost unstained.
The stained portion is inserted upon the regular
dentine by means of numerous shallow excava-
tions, and its sm-faee is irregularly jagged toward
the pulp-cavity. In the apex of the root the irregu-
lar formation of dentine again is much thicker
than in the middle portion, and provided with
numerous roundish spaces, all of which contain
plastids, and communicate with the irregular,
wavy canaliculi of the boundary layer of the
pulp-cavity.

In the tooth just described we have a forma-
tion which is known by the term ' ' secondary
dentine." The literature of this subject is con-
cisely presented by Carl Wedl,* fi'om whom I
quote the following note :

"J. Hunter t says: 'In teeth which are worn
away by attrition, that portion of the pulp-cavity
adjacent to the abraded surface becomes filled
with a new substance, which occupies the center
of the abraded surface, and generally is softer
than the rest of the tissue of the tooth.' Prochaska} treated of the same
subject in his * Observat. Anatom. de Decremento Dentium Corp. Humani.'
Oudet ^ gives a good description of these new formations, which he divides
into two classes — the adherent and unattached. He paid no attention to
their histological structure. . . . E. Owen || illustrates numerous new
formations of osteo-dentine, but does not go very deeply into the subject.
Salter H treats of osteo-deutinal formations in addition to simple calcifiea-

FiG. 272.— Root op an
Anomalous Canine
Tooth.

D, dentine ; C, ccinentiim ; P,
pericementum. Magnified 1000
diameters.

* "The Patliologyof tlie Teetli," Philadelphia, 1872.

t " Natural Histoiy of the Teeth," 1778.

t Adnotat. Academ. Frag. 1780.

? " Dictionnaire de Medecine," article "Deut," 1835.

II " Odontography," 1840-45.

IT Guy's " Hospital Reports," ix.

THE TKKTH.

633

tiona of the pulp, calcareous ^-ainilar deposits. He regards them as the
result of a patliological process. We are indebted to J. Tomes " for their
first minute anatomical dcscri])tion, and to F. Ulrich, t who distinj^uishes in
them two kinds of tissues — adentinoid, an osteoid, and a coml)iiiation of the
two. Wedlt and Heider and Wedl \\ fjive further anatomical details, and the
latter endeavor to determine the mode of development (jf these new forma-
tions. R. Hold II furnishes a critical treatise, based upon independent inves-
tigations, and applies to these formations the terms odontoma, osteoma, and
osteo-odontoma."

John Tomes and Charles S. Tomes H say as follows : " With the advance of
age, the area of the pulp-ca^-ity becomes gradually diminished by the slow

t

Fig. 273. — Cusp of an Anomalous Canine Tooth.

D, dentiue ; SI), secondary dentine ; P', pear-shaped bioplasson bodies on the bountlarj-
between primary and secondary dentine, sending large offshoots, O, downward; P», bioplas-
son body without ottslioots. Magnified 500 diameters.

addition of dentine to that which was formed when the tooth was in a state
of active growth ; and this condition is still more strongly marked in those
teeth which have been worn by mastication ; indeed, in some eases the cavity

■■' "A Course of Lectures on Dental Physiolojry and Surgery," 1848.

t Zeitschrift der k. k. Gesellschaft der Aerzte zu Wien, 1851.

t Grund/.iige der Pathol. Histologie, 185-1.

S Deutsche Vierteljahrssclnift fiirZalinheilkunde, 1864.

II " Monographie iiber Xeubildungen der Zahnpulpe," 1868.

II " A System of Dental Surgery," Philadelphia, 1873, p. 307.

634 THE TEETH.

is almost, in others perfectly, obliterated. In either case the effect is, as
respects the contraction of the cavity, general, but the local development of
dentine continuous with the preexisting tissue is very often coincident with
caries. When the crown of the tooth is attacked, the pulp very commonly
resumes its formative functions at a point corresponding to that toward
which the disease is advancing, and adds, as it were, a patch or plate of new
dentine (or secondary dentine, as it is commonly called).

S. James A. Salter* says: "Considering secondary dentine as applicable
to all the after-formations of dentine by which the pulp-cavity is diminislied or
obliterated, I would subdivide it into dentine of repair, dentine excrescence,
and osteo-dentiue. I first suggested the arrangement in the 'Guy's Hospital
Keports'for 1853. Osteo-dentine and dentine excrescence are not infre-
quently seen in teeth that are worn and exhibit dentine of repair. Dentine
of repair, however, always forms upon that portion of the pulp-cavity next to
the lesion, and is adherent and in direct structural continuity with the pri-
mary dentine, whereas osteo-dentine and dentine excrescence occur almost
always fii-st toward the extremity of the root, and the former is frequently
quite detached from the remainder of the dentine. Mr. Salter asserts against
Tomes (page QS), that 'the circumstance of age, per se, is really not efficient
for the production of secondary dentine ; and the fact that the teeth which
exhibit secondary dentine are usually from aged subjects is merely accidental,
and dependent upon the fact that it is in them that the teeth are most worn.
Dentine excrescences are little nodules of secondary dentine, occasionally
found attached to the interior of the pulp-eaWties of teeth which may be
otherwise healthy, unassociated with injury or other disease. Osteo-dentine
is a form of secondary dentine in which the tissue combines the characters
both of bone and ivory. It is usually vascular ; it is fi'equently arranged in
systems arovmd vessels, like the Haversian systems in bone, and it sometimes
contains true lacimse."

C. Wedl (1. c.) accm-ately describes the new formations of the hard tissues
of the teeth. When speaking of the new formations in the piilp-cavity, he
says : " In these cases there occurs a continuous development of dentine
within certain limits, determined by an in-itation, and the new layers are
deposited in immediate contiguity with the old, and in parts are intimately
and organically united with the latter. Dentine of this description, which
serves as a protective covering of the pulp, is called 'dentine of repair,' —
'secondary dentine,' as is that dentine, also, which is formed in cases of
chronic caries upon that portion of the wall of the pulp-cavity corresponding
to the carious locality, and projects into the carious ca^^ty in the form of a
spherical segment. In the latter eases, also, we find that the new dentinal
canals are continuous with the old ; there is usually an abundant basis-sub-
stance, and the canals are separated by quite wide intervals. A different
structure is presented by the concentrically laminated forms, two varieties
of which are distinguished — the simple and complex. ... I have met with
a few cases only of true new formations of osseous substance within the par-
enchjTna of the pulp. The greater portion of the very common osteo-dentine
formations is composed of dentine ; the bony substance occurs in a very small
quantity, and may consist merely of a group of a few bone-corpuscles. The
osseous substance not infrequently attains only a rudimentary development,
and resembles that which occurs upon the cement toward the neck of the tooth."

' " Dental Patlioloi^y and Surpery," New- York, 1875.

Till': TKi'/iii. (;:}r>

Cliiirlcs S. Tonios * says: " SccoiulHry ilcntin*^ occiirH in tho tcotli <if' iijjcd
persons, in wliii-li llm ]>tilj>-t'iivity is much coiitnictcd in size, and also is very
frtMiucMitiy t'onncd as a protection li> the iJiilji. ulnn thn'ati'ncd V)y the
ai)proacli of dental caries, or by (he thiiinin;; of the walls of tlie pulp-
eavity tlirouf^li excessive wear." Tomes illustrates secondary dentine
lilliufx up one of tlie cornua of the pulp-cavity from a human molar affeetetl
by caries, which figure closely reseinbles the formation I have ileseribed
above. Tomes remarks: "It would be impossible to attempt to give any
description of the almost endless minor modifications of the dentine
structure."

From the facts recorded in dental literature, it is cvidc.nf fliat there are
several causes universally agreed upon as to formations of secondary dentine.
These causes are mainly : Fiynt, advanced age ; second, caries of the primary
dentine; and, third, injuries on the external surface of the tooth.

C. Heitzniuiin t (irst drew attention to the fact that in old dogs and cats
a number of Haversian canals in the compact bone become obliterated. This
investigator observed that the capillary blood-vessel, which represents the last
remnant of the medullary tissue within the Haversian canals, is finally trans-
formed into a solid mass, whicli immediately assumes the character of the
bony basis-substance. The bone-corpuscles, which under these circumstances
are visible in the center of a Haversian system, are as a rule larger than those
scattered within the lamelliK of an earlier formation.

If we consider the pulp-cavity as a medullary space containing l)loo(l-
vessels, nerves, and medullary elements, around which are arranged the layers
of dentine, enamel, and eementum, we find a coincidence of the formation of
bone on the one hand, and of secondary dentine on the other, in advancing
age. In both instances the medullary elements are transformed into basis-
substance ; the nerves, probably, after having been reduced to medullary
elements, also assisting in the formation of secondary dentine ; and, lastly,
the blood-vessels are solidified. On an average the pulp-cavity is the smaller
the older the person, until at last hardly any trace of the pulp-tissue is left,
and the tooth represents an almost completely solid mass.

Opposed to carious destruction of the crown I have repeatedly met with
formations of secondary dentine, as described by Salter and Wedl. This
occurred, however, only in those forms of caries which have been described
by Frank Abbott as chronic.

As to the irritation from without, first stated by Salter to be the cause of
the formation of secondary dentine, I would add chronic pericementitis, which,
when limited to one root or to a portion of the root, leads to the formation of
secondary dentine in the pulp-canal of the affected root. This fact strongly
supports my assertion that the tooth in its normal condition is living, and
irritation of the external surface may result in a new i)roduction on the corre-
sponding inner surface of the dentine. There are instances, however, in
which neither age nor an external injury accounts for the formation of
secondary dentine ; and such an instance is that of the tooth above described.

The coarser anatomical relations of secondary dentine in general are
accurately described by C. Wedl, with whom I fully agi-ee. In analyzing
the manifold formations of this kind, I would divide them as follows :

" "Manual of Dental Anatomy," Pliiladelplila, 1876.

t " Ueber Riick- iiud XeubiUlung von Blutgefassen in Knorpcl und Kiioclien." Wiener
Medicinisclic Jalirbiiclier, 1872.

636 THE TEETH.

First. Secondary dentine resemhlinfj; ])riinary dentine.
SccotifL Secondary dentine with a laminated structnre.
Third. Secondary dentine in form analogous to Haversian systems. This
latter variety has been termed " osteo-dentine."

Secondary dentine, with the essential structure of primary dentine, is
evidently the most frequent occun-ence. It never has the regular arrange-
ment of the dentinal canaliculi as seen in primary dentine, but is marked
by a lighter color, owing to the larger amount of basis-substance and the
relatively small number of canaliculi, which at the same time deviate more or
less from the direction of the primary canaliculi. In cross-sections of such
secondary dentine — especially in specimens stained with chloride of gold —
we recognize in each canaliculus a central fiber, from which delicate conical
offshoots emanate toward the periphery of the canaliculus. The canaliculi,
which as a rule are the wider the nearer to the pulp-
cavity, are pierced on their periphery by light inter-
^pjj ruptions, leading into a delicate, light reticulum
throughout the whole basis-substance. (See Fig.
274.) This secondary dentine sometimes remains in
an embryonal condition, exhibiting roundish fields of
7 . basis-substance, such as are visible in the dentuie of

iv J a nine-months foetus. The medullary elements, being

f "" -"*" transformed into basis-substance, represent irregular

I globular bodies, between which the living matter pro-

- ^ duces the formations known as dentinal fibers. The
origin of these fibers will be fully understood only
after thorough investigation of the development of
dentine. This much is certain, that the regular fibers
Fig. 274.— Dentine ^f secondary dentine are also beaded, and send lateral
OP AN Aged Per- offshoots toward the basis-substance, thus indicating
SON. Cross -Sec- ^^g presence of living matter in the latter. (See Fig.
TION. 275.)

JPD, primary .lentine ; Formations known as "interglobular spaces" are

ZD, .secomlaiy (\tntiiir. j^^t infrequently met with in normal dentine. They
Magnifled 1000 diam. ^re also (luite common in secondary dentine, especially
on the boundary between primary and secondary den-
tine. The tooth first described furnishes beautiful samples of such forma-
tions. Most of these are filled with bioplasson, some exhibiting nuclei. The
offshoots are evidently fibers of living matter. Some of these, toward the
primary dentine, are in direct communication with its fibers ; others run in
different directions toward neighboring kindred formations, with which they
inosculate ; others, again, after repeated bifurcation, lose themselves in the
basis-substance. Exceptionally there occur also bioplasson bodies without
any coarser offshoots. (See Fig. 27.3.)

With higher amplification we see bioplasson bodies imbedded in lacunas of
the basis-substance, essentially identical with the so-called "interglobular
spaces," the tenants of which never could have been made out in sections
obtained from dry teeth. The plastids send larger beaded fibers in different
directions into the basis-substance, which are partly in communication with
fibers arising from neighboring bodies. (See Fig. 276.)

The second variety of secondary dentine consists of the formation of a
lamellated basis-substance, which is traversed by irregular dentinal canaliculi.

THE TEETH.

(VM

Fig. 275. — Secondary Dentine, with Globular Formations
OF THE Basis-substance.

PD, primary (U'litiiie; SI), secondary dentine, with irregularly scattered canalicnli ; IB,
fflobular bodies of secondary dentine, between wliicli the dentinal canalicnli run, all in connec-
tion with those of the primary dentine. Miifrnified 500 diameters.

I have observed fi-oni my specimens that the lamellated structure begins close
to the termination of the primary dentine in an almost contiimous course.
The lamellae themselves never are very regular, and produce broader and nar-
rower layers which, as a rule, are not strictly parallel to each other. In the
interstices between the lamellae, here and there, I have met with flat layers of
bioplasson. The eanaliculi piercing the lamellated dentine are generally very

Fig. 270. — Secondary Dentine from Canine.

P, bioplasson bodies with the reticular .structure and offshoots; B, basis-substiince with
the light, net-like structure. Magnified 1000 diameters.

638 THE TEETH.

narrow, and run either in a rectangular or in an oblique direction to the lamellae,
with manifold ramifications. They invariably contain delicate beaded fibers of
living matter, whicli send lateral conical offshoots toward the basis-substance,
in a much more irregular distribution than we see in primary dentine.

Fig. 277, whicli illustrates the lamellated variety of secondary dentine,
exhibits a peculiar feature of dentinal canaliculi in the primary dentine, near
its connection with the lamellated formation, — viz. : bifurcations of the ca7i-
aliculi of the primary dentine, — which otherwise do not occur except on their
terminations near the enamel and the cementum.

In this group I would enumerate also those peculiar formations which
have long been known by the term of "pulp-stones." The process leading to
their production is 1)y no ineans a mere deposition of lime-salts, but a trans-
fornuitionof the pulp-tissue, partly, at least, identical with lamellated dentine.

The third, and evidently rarest, form of secondary dentine is that known
by the term "osteo-dentiue." Formations of this kind are either jjeduncu-

•pn

Fig. 277. — Lamellated Variety of Secondary Dentine.

P/), primarj' (leutiue ; SX), secondaiy deutiue ; P, margin toward the pulp-cavity, with
bay -like excavations, diu' to imlpitis. Tlie lamella' of the secondary dentine are irregular and
pierced by dentinal fibers, which are piirtly in direct connection with those of the primary
dentine. Magnified 500 diameters.

lated — viz.: in connection with the primary dentine by a stem — or they
partly fill the pulp-cavity in the shape of a uniform layer. Thei*e is a striking
resemblance between osteo-dentiue and Haversian systems of bone-tissue.
The systems greatly vary in size and shape, and are separated from each
other by a tissue kindred to primary dentine, but devoid of dentinal canali-
culi. Each system has in its center a tneduUary canal, containing a certain
amount of plastids known as medullary elements — nay, iti some of the sys-
tems I have met with a central capillary blood-vessel, which has evidently
been in direct union with capillaries of the pulp-tissue. Around the medul-
lary canal a system of lamellse is arranged, sometimes pretty regularly, and
the lamellae are traversed by delicate radiating canaliculi, closely resembling

TiiK TKirni.

089

those of l>o!io-tissut». Only oxiH-ptionally liave I seen witliin the laiiiellie \no-
plasson formations anaK>fjous to bone-etirjiuseles. (See Fij^. 'J7>».)

In the sj)eeiinen from which I have selected a spot for illustration, the
lamellated systems were develojied in a most marked manner; and the blood-
vessels in the center of these systems were so regular that they suggested the
<iuery whether or not we had here to deal with vaso-dentine, so common in
the teeth of tish. These formations occurred in the apex of the root, — some
of them in the middle of regular dentine, — while the lowest systems, without
any distinct boundary, were connected with the cementum, which latter, here
and there, also exhibited medullary canals.

In a large number of specimens of secondary dentine I was struck by the
presence of l»ay-like excavations on the boundary of the pulp, filled with
medullary elements or multinudear bodies (myeloid boiiies or myeloplaxes).
The pulp-tissue exhibited all the features of inflammation, to which also the

EP

■SD

Q^

Fiti. 2 7S. — U6TEO-DENTINE, THE THIRD VARIETY OF SECONDARY DeNTENE.

-'\ primary dentine; S/K secondary dentine: SL, system of lamella-, resemblius those of
Haversian s3-stems of bone : MC. medullary canal filled with bioplasson : JiC. small plastids.
ideniieal with bone-corpnscles ; EP, erosions of osteo-dentine due to puliiitis. Magnified tiOO
diameters.

bay-like excavations in the secondary dentine were doubtless due. If we con-
sider the formation of secondary dentine as the result of a slight but long-
continued irritation, we readily understand that such an iiTitation may
occasionally terminate in an inflammatory process — so-called pulpitis. The
newly formed dentine, partly at least, will be destroyed by the inflammation,
and thus produce a combination of both formative and destructive processes,
so common in inflammation of bone-tissue. The presence of inflammation
would also explain the pain which sometimes accompanies the formation
of secondary dentine.

640 THE TEETH.

The Pulp of the Tooth. By C. F. W. Boedecker, D. D. S., M. D. S.*

(1) Mctliods. Tlie best method for the examination of pulp-tissue is to
place the tooth, immediately after its removal from the mouth, in an aqueous
solution of clu'omic acid, of one-half to one per cent, in strength, to which
from time to time a few drops of dilute hydrochloric acid may be added.
After a few weeks the peripheral portion of the dentine has become suffi-
ciently soft to be cut by a razor. When, in cutting, the hard portions of the
dentine are reached, the extraction of the lime-salts must be continued in the
above described manner until the razor meets with the central cavity and its
tenant, the pulp.

Another method is to split the tooth, as soon as possible after its extrac-
tion, with a strong pair of excising forceps. The teeth best adapted for this
method are the incisors, canines, and bicuspids. Immediately moisten the
exposed pulp with a solution of chloride of sodium, of the strength of about
one-half per cent., and then remove the pulp. K the pulp is to be stained
with carmine, hsematoxylon, fuchsine, osmic acid, picro-indigo, or chloride of
gold, etc., after its removal from the hard parts of the tooth, place it in the
staining fluid. Among the re-agents mentioned, I have found but one of con-
siderable value — viz. : the one-half per cent, solution of chloride of gold.
This re-agent can be applied to fresh pulps as well as to very thin sections
obtained after hardening in chromic acid. It may be allowed to remain in
contact with the specimen for from twenty to thirty minutes. In a few days
fresh specimens will assume a bright violet color, while sections which have
previously been in a chromic acid solution become brownish-violet. Osmic
acid, in a solution of one per cent., renders the contours of the constituent
tissues, and especially those of the medullated nerve-fibers, more distinct.
Both fresh and chromic acid specimens may be treated with it. Thin sections
do not require more than one hour's exposure to this re-agent, while whole
fresh pulps may be left in it for two or three hours. Except the ammoniacal
solution of carmine, which is known to be suitable for staining certain parts of
the tissue, I would not lay stress upon applying any of the other re-agents
mentioned.

If a fresh pulp is thin enoiigh it may, immediately after its removal from
the split tooth, be transferred to the slide with the addition of an indifferent
fluid, such as the solution of chloride of sodium. Fresh pulps of lower incisors,
being the thinnest, are best adapted for examining the system of blood-vessels ;
shortly afterward, however, the vessels fade away. Isolated pulps may be
placed between two plates of fine cork, and thus cut into thin sections with
the razor.

( 2 ) The minute structure of normal pulp-tissue. K we examine a thin longitu-
dinal or transverse section of the pulp with low powers of the microscope, we
recognize a large number of blood-vessels and bundles of medullated nerve-
fibers. The majority of these blood-vessels are capillaries ; the veins are less
numerous and the arteries scarce. In many pulps we find no arteries at all,
in others a limited number, particularly in the root portion of the pulp, and
also in the middle of the medullated nerve-bundles. The latter mostly run in
a longitudinal direction, but not infrequently we observe smaller bundles, or

* Abstract of the author's paper, "Tlie Miuute Anatomy of the Dental Pulp in its Physio-
logical anil Pathological Couditions." The Dental Cosmos, Philaclelpliia, 1882.

THE' TEE TIT.

041

siiif^lo nu'dullatod nerve-libers, divergiiiiE? from the loiigitiulinal direction iind
running ()lili([uely throujjch the pulp-tissue. In transverse sections of thejiulp
it often happens tluit the nerve-fibers fall out, and then we soo a roundish,
empty space bounded by tho sharply defined external perineurium. The
aVtsence of an endothelial coat renders such spaces easily recognizable in
contradistinction to blood-vessels.

Tlie main mass of the pulp is composed of a delicate fibrous reticulum,
containing a large number of bright, shining corpuscles. Longitudinal sections
in many instances exhibit delicate fibrous bundles scattered throughout the
reticular structure of the pulp, mainly in the neighborhood of larger blood-

FiG. 279. — Pulp of a Molar. Longitudinal Section.

M, inyxomatoiis tissue ; T', vein ; N, buntllo of moiUillatcd uerve-fibers ; C, caiiillary
bloort-vessol ; B, sramiliU' Uij'er of basis-substauce ; JF, noii-moduUatetl terminal nerve-fibers :
O, laj-er of ortoiitobla.sts. Maguified 200 diauieters.

vessels and nerve-bundles. Pulps composed of a fibrous connective tissue
only are exceptional, and, without relation to the age of the person, very
probably the result of morbid processes. Toward the outer siu'f ace of the pulp
the reticular structure, as a rule, is denser than in the middle portions. This
peripheral part is surrounded by a WTcath of elongated formations, arranged
in a radiating manner, the so-called " odontoblast layer." (See Fig. 27!).)

Higher amplifications of the microscope reveal a minute reticular structure,
consisting of delicate fibers, or anastomosing bioplasson cords, with very
41

642 THE TEETH.

smiiU, oblong nuclei at their points of intersection. The meshes either look
pale and finely granular throughoiit, or contain a bright yellowish, either
homogeneous or gi-auular, body of the size of a nucleus. The number of the
latter formations greatly varies in different pulps. Where bundles of a fibrous
tissue traverse the reticulum, the latter blend with the former.

In longitudinal sections the medullated nerves show the well-known fluted
double contour — the sheath of Schwann. It exhibits delicate oblong or
spindle-shaped nuclei. External to this we observe a delicate layer of fibrous
connective tissue, the " internal perineurium." In cross-sections of the nerve-
bundles more or less circular groups of medullated nerve-fibers are seen, each
of which in its center exhibits the axis-cylinder in the shape of a roundish,
glistening dot. Not infrequently capillary and arterial blood-vessels are met
with between the nerve-fibers.

As to lymphatics of the pulp, I can say that in some specimens I have seen
branches of vessels of the size of veins without an adventitial coat, being
composed of large, flat, and slightly protruding endothelia.

At the periphery of the pulp the delicate reticulum constituting the pulp-
tissue is very dense ; here we meet with narrow capillary blood-vessels only.
The outer surface of this layer is often uniformly granular, and bounded by
radiating rows of shining corpuscles.

In chromic acid specimens stained with carmine, or, still better, in those
treated with chloride of gold, high amplifications (1000 to 1200 diameters)
reveal an extremely minute reticular structure pervading all formations of
the pulp. Starting from the center of a mesh of the mj^xomatous tissue we see
a nucleus, either homogeneous and apparently destitute of structure, or of the
appearance of a vesicle with a distinct bright wall. Inside the hollow nucleus
we see a varj-ing number of bright granules interconnected with each other, as
well as with the inclosing wall, by means of delicate filaments. Such filaments
connect also the nucleus with the extremely delicate gi'ayish reticulum in the
light basis-substance contained in the mesh. This reticulum in the basis-sub-
stance is recognizable even though the central nucleus be absent. The
fibrous or bioplasson net-work which incloses the mesh-spaces also shows a
delicate reticulum in connection with the nuclei at the points of intersection.

The foiTnations at the periphery of the dental pulp, termed odontoblasts,
under high amplifications exhibit the following : Elongated fields, somewhat
resembling epithelia, border the pulp in a radiating dii-eetion. Each field may
appear in the shape of a granular bioplasson, or in that of basis-substance, in
either of which oblong nuclei are imbedded in varjdng numbers. The nuclei
exhibit coarse gi-anules and a dense reticulum of li\4ng matter. The bioplas-
son bodies are separated from each other by delicate light rims, in which we
see sometimes broad, sometimes delicate, transverse fibrillaj in connection
with the reticulum of the neighboring formations. The bioplasson bodies or
odontoblasts fm-nish the matrix for the basis-substance of the dentine, while
the dentinal fibers, being formations of living matter, originate between the
odontoblasts.

The medullated nerve-fibers, upon approaching the periphery of the pulp,
become destitute of their myeline sheath, and, now being bare axis-cylinders,
branch into nimierous extremely delicate beaded fibrillie — the ''axisfibrillae."
These terminate, with knob-like extremities, in the granular layer beneath
the odontoblasts, or they penetrate the light rims between the rows of the
odontoblasts, and are connected with the latter by means of delicate conical

THE TEETH.

(m

e?-"

spokos. Wli ether the nerve-fibers directly inosculate with the dentinal fibers,
I am unable to say ; but I can positively maintain that an indirect connection
of the two is established by the iiitorvoning reticulum of living matter. (See
Fi-. L'SO.)

The results of ray researches of normal pulp are as follows :

1. The dental pitlp is a rariclij of coiutcctire tissue termed myxomatous, rep-
resentiufi its embryonal form, rulp-tissne, therefore, is a remnant of embryonal
tissue, and Li nd red to the formations termed "adenoid tissue.'"

2. The myxomatous tissue of the pulp is intermixed with a delicate, fibrous cou'
ncctire tissue in varying amount. I'ulps
entirely, or nearly, built up by fibrous
conneetive tissue arc not to be considered
physiohnjical.

3. The pulp-tissue is traversed by a
system of blood-vessels — viz. : arteries,
veins, and capillaries. Arteries, however,
are not invariably found. Lymphatics in
small numbers are also present.

4. The jiulp-tissuc is richly supjdied
with nerves, which as bundles of mcduUated
nerve-fibers traverse the myxomatous tissue.
Toward the periphery of the pulp they be-
come non-mcdullated, and terminate as
minute beaded fibrillar in knobs or between
the odontoblasts.

5. The odontoblasts, at the periphery
of the pulp, are rows of bioplasson forma-
tions, in part with nuclei — i. e., medullary
corpuscles — such as we see wherever a new
tissue arises from a former.

6. The dentinal fibers originate between
the odontoblasts. Being formations of liv-
ing matter, they are in direct connection
with the reticulum of living matter ; first
of the odontoblasts, and afterward of the
basis-substance of the dentine. The con-
nection between ultimate nerve-fibrillce and
the dentinal fibers is very probably indirect.

Pulj)itis. I have examined a large num-
ber of specimens of pulpitis, but have
not met with this process unless in pulp-
chambers more or less reduced in their caliber by a new formation of secondary
dentine. If pulpitis oecm-s at all without the pi'e%'ious formation, of secondary
dentine, this must be rare. Even where primary dentine is invaded by the
inflammatory process, traces of secondary dentine are \'isible scattered along
the pulp-chamber, and the probability is admissible that the secondary dentine
has been destroyed by the inflammation to a gi'eat extent before the primary
dentine was reached.

The main characteristic of this process is the appearance of a large number
of inflammatorj' or medullary corpuscles in the pulp-tissue. These corpuscles
arise from the bioplasson formations as well as from the liv-ing matter hidden

Fig. 2 so. — Pulp of a Temporary
Molar. Stained with Chlo-
ride OP Gold.

M, myxomatous tissue ; O, rows of
medullary corpuscles — so-called odonto-
l)lasts : i>, dentine ; F, dentinal libers ; iV,
terminal n(m-medullated nerve -fibers.
Majmilied 1200 diameters.

044 THE TEETH.

in the basis-substance. Wliere before a filjrous reticulum was visible contain-
ing in its meshes a basis-substance with central nuclei, in the earliest stages
of inflammation numerous ])lastids are seen, either closely packed together in
clusters or separated from each other by layers of a gi-anular bioplasson.

The process of inflammation in many instances does not invade the whole
of the piilp at the same time, but only in part.

The manner in which the inflammatory corpuscles make their appearance is
as follows : Portions of living matter of either the myxomatous retic^ilum and
its nuclei, or of the basis-substance (evidently after its liquefaction), grow into
shining homogeneous lumps, from which nucleated plastids arise by a differen-
tiation of the living matter into a reticulum. The li\'ing matter of tlie nerve-
fibers likewise furnishes material for the formation of inflammatory corpuscles,
which in slight degrees of this process are traceable in the shape of longi-
tudinal rows. In higher degrees even these reminders of former nerve-
bundles are lost. The blood-vessels soon perish on a lai'ge scale. Even in the
early stages of pulpitis we have difficulty in tracing blood-vessels, as most of
them are either compressed or made impermeable by a process of solidification
and si)litting into inflammatory corpuscles. Where blood-vessels are seen
unbroken, they appear considerably dilated and engorged with blood-corpus-
cles. The arteries resist the destmction for the longest period of time. An
artery in one of my specimens, cut transversely, shows the concentric layer
of smooth muscles, divided into small lumps, and in its caliber a large num-
ber of inflammatory corpuscles, which have e\adently sprung from prolifera-
tion of the endothelial coat.

As the process of pulpitis advances, at first the secondary and afterward
the primary dentine is destroyed to a greater or less extent. The solid basis-
substance of the dentine is at fii'st deprived of its lime-salts, after which the
gluey portion is liquefied. This process invariably takes places in the globu-
lar teiTitories of the dentine, and by coalescence of such territories bay-like
excavations originate in the dentine, at first with faint outlines, and afterward
sharply defined from the calcified basis-substance. In consequence of the lique-
faction, the original bioplasson condition of the dentine is reestablished. K
the inflammatory process is slow or chronic, it may happen that from a former
territory of dentiue, by a process of recalcification, a territory of bone is formed,
in the center of which we recognize an oblong branching bone-corpuscle. This
formation, however, is rather exceptional. The rule is that the bioplasson
filling a bay-like excavation becomes supplied with a number of new nuclei,
thus representing the stage of a multiuuclear body. Such a mass splits into
a large number of inflammatory corpuscles, the sum total of which, in the bay-
like excavations as well as in the pulis-tissue proper, establishes a condition
termed infammatury infiltration. (See Fig. 281.) In milder forms of inflam-
mation the pulp-tissue, although considerably changed, still remains a tissue,
viz. , as long as the delicate filaments of living matter interconnect the single
inflammatorj' corpuscles with one another. Should the inflammatory process
abate at this stage, the tissue may proceed to the formation of a new basis-
substance. Every variety of connective tissue, once inflamed, becomes a fibrous
or cicatricial tissue. It is quite possible, therefore, that the few pulps I have
met with exhil)iting the structure of fibrous connective tissue, and scantily
supplied with blood-vessels, are the products of a former inflammation. It is
also probable that an advance to the formation of other tissues found in the
pulp, such as dentine and bone, is the result of a slight inflammatory condi-

TIIK TKETll.

()4r)

tioii, whifli (lul not extiMid iibovo the stage of hyperplasia or hypertropliy. In
a few speeiinens of mainly fibrous striieturc, I have seen the bundles of
mcdullated nerve-fil)ers transformed into rows of fat-globides.

Slionld the inflamnnition reaeli a high degi-ee, the inflammatory corpuscles
will become separated from each other,— torn apart, — and the result is the
formation of pus, which, as a Tuatter of course, is no subject of microscopical
research. An intense inflammatory process very soon may lead to an engorge-
ment of the afferent vessels and their strangulation by pressure. In this
instance, death and putrefaction of the inflamed pulp will ensue.

('(ih-ijic(ifii>)i find Hdxi/ Dct/oicraiidii. Deposition of lime-salts in the pulp-
tissue is very common. It presents itself in the shape of globular, elongated,
or irregular formations, of a more or less lobate surface and a high degi-ee of
refracting power. The age of t!ie pcraoa apparently has nothing to do with

-.7/

Fig. 281.— Pulpitis.

S, secoiulKrj' dentine: B, bay-like excavations filled witli medullary or iuflaiumatory
corimscles; M, multiuiiclcar body; V, blood-vessel in transverse sectiou. Ma-ruitied 300
diameters.

the calcification of the pulp. I have numerous specimens of calcified pulps
from apparently sound bicuspids and fii-st and third molars of young persons,
which were extracted on account of irregularity or want of room. Some
of the wisdom teeth were removed when only one or two of their cusps
had pierced the gums ; still, their pulps exliibited calcareous depositions, as
well as eburnifications.

Pulps containing a larger number of calcified spicule, as a rule, exhibit
more fibrous connective tissue than myxomatous. Around the calcareous
masses invariably a dense ensheathing layer of fibrous connective tissue has

646

THE TEETH.

formed. Where these masses had fallen out, an empty, fibrous sac is left
behind. (See Fig. 282.) I am unable to observe any positive connection
between the blood-vessels and the calcified masses ; though sometimes a
capillary blood-vessel maybe attached to the capsule ensheathing the calcified
mass, or it may occur that a capillary vessel is dilated like a small aneurism,
and contains a calcified mass.

A peculiar change of the pulp-tissue, which I have observed both with and
without calcifications, is much rarer. It consists of a transformation of the
myxomatous tissue into a shining, nearly homogeneous, mass, devoid of a dis-
tinct demarcation toward the unchanged tissue of the pulp. In this homoge-
neous mass, which may vary greatly in extent, we recognize granular, stringy
formations, and sometimes smaller bundles of nerve-fibers, not noticeably
changed in their structure. In some instances, the nerve-fibers within such
fields were dark and coarsely granular, as if composed of crumbs.

Fig. 282. — Calcification of Pulp.

C, calcareous (lei)ositi(HiHin liolds coi-responding to forintr meiluUary coipuscle.s ; M, mert-
ullaiy corimscle not Infiltrated with lime-salts ; P, i)lasti(l in the niiilille of the calcified mass ;
F, capsule of fibrous connective tissue. Majn'ified 500 diameters.

All I can say as to the re-agents applied is that the homogeneous mass
stains readily with carmine.

Changes of tissues of this character are common in different organs, espe-
cially in the spleen, the liver, and the kidneys. They always indicate a low
degree of nutrition, and are said to be especially caused by sj-philis. This
change bears the name of " amyloid or waxy degeneration." Its nature, how-
ever, is far from being known.

DcnUmfication, Ehurnification, and Ossification. It was necessary to offer
new terms for the designation of a process which, althotigh known for many
years, never has been fully understood. I refer to the new formations of den-

THE TEETH.

G47

tine in the niiilillo of tlie pulp-tissiie, indejiendent of the dentine composing
the walls of the pulp-ehiiniber — the so-called " jiulp-sUmen." They, us is well
known, may be found eitlier in connection with the dentine proper, by means
of a pedicle, or loosely imbedded in the connective tissue of the pulp.

Most of these formations are composed of dentinal tissue, in the form
termed secondary dentine. Rarer occurrences are those exclusively con-
structed of a laminated bone-tissue. Somewhat rarer are combinations of
both dentine and bone-tissue. The rarest are new formations of dentine
strictly identical with primary dentine.

1. l'i(l2)-f<fo>tcs of the Character of Secondary Dentine. The characteristic
feature of this variety is the presence of dentinal canaliculi iiTegularly scat-
tered throughout tlie calcified basis-substance. Sometimes the canaliculi
assume a tolerably well-marked radiation ; at other times, large masses oi cal-
cified basis-substance are destitute of canaliculi, which, in scanty bundles, are

Fig. 283. — Eburnificatiox of the Pulp.

X, irregular laniellip, traversed by radiating deutinal canaliculi ; CC, coucentricallj' stri-
ated globules (osteo-deutine). Magnified 300 diameters.

present toward the periphery of the pulp-stone. All the three varieties of
secondary dentine (see page 63G) may be found. Portions of the basis-sub-
stance, especially toward the periphery, may exhibit delicate concentric lam-
inations. In the middle of an apparently homogeneous basis-substance, small,
lamellated temtories may occur, containing a central corpuscle with branch-
ing offshoots somewhat resembling a bone-corpuscle. In sections of one
pulp-stone I have found numerous concentrically laminated territories, with
either distinct or indistinct bioplasson formations in their centers. The mass
between the territories was partly granular, partly composed of a tissue, like
secondary dentine, with irregular canaliculi. Here and there medullary

648

THE TEETH.

spaces were seen traversing the tissue, from which, evidently, the new fonna-
tion of the territories had started. This variety is regular osteo-dentine.
(See Fig. 283.)

2. Pulp-fitoncs Composed of Regularly Developed Laniellated Bone. I have
ohserved pulps almost exclusively composed of a dense, fibrous connective
tissue, the bundles of which were interlacing, so as to establish a regular
cicatricial connective tissue. Scanty nerve-bundles and blood-vessels trav-
ersed this tissue, which in some places appeared to be more or less crowded
with medullary or inflammatory corpuscles. In such fibrous pulps I have seen
formations of fully developed bone-tissue, composed of more or less regular
lamellae, or of calcified fibrous lamellfe. In them a large number of iiTegular
branching bone-corpuscles were seen, an-anged in rows or chains, where the
basis-substance was of a more fibrous character. Sometimes the bone-tissue

Fig. 284. — Ossification of the Pulp.

L, longitudinal ; T, transverse sections of bundles of cicatricial fibrous connective tissue ;
B, spiculse of laniellated l)one, with regularlj' developed boue-corimscles. Magnified 500
diameters.

appeared in lamellated islands, shai-ply marked from the surrounding fibrous
tissue. No formatioti of secondary dentine was found in these cases. (See
Fig. 284.)

3. Pulp-stones Composed of a Mixture of Regular Bone and Dentinal Tissue.
In rare instances I have met with pulp-stones composed of partly secondary
dentine and lamellated bone, in such a way that irregularly Ijounded masses
of bone contained a few large bone-corpuscles, and were surrounded by a
basis-substance which held exclusively irregular, wavy, dentinal eanaliculi.

4. Pulp-stones Composed of Dentine, with the Features of Primary Dentine.
One of the pulp-stones which I examined was a mass about the size of a pea,

vv/A' tki<:tii.

040

and built up by dentine. The cantilicuii of tliis dentine are parallel, and
between tlieni is a finely reticular basis-substance, arrauf^ed as in the primary
dcMitine of tenii)orary tooth — i. c, poorly supplied with liin(!-8alts. The den-
tinal canaliculi are very wide; the basis-substance between them, on the con-
trary, is luirrow. The rej^ular dentine toward the perij)hery of the pulp-stone
is bounded by a narrow zone, which exhibits the structure of seeoTidary den-
tine. This again blends with u still
narrower one composed of an indis- ;ffll'^.'.
tinctly lamellated bone-tissue, with
scanty but large bone-corpuscles.
The bony layer is followed by the
bounding layer of the specimen, of
a granular appearance, containing
scanty, angular or spindle-shaped
bioplasson bodies and a few den-
tinal canaliculi. (See Fig. 285.)

C. Wedl is of opinion that these
formations arise fi-om an inversion of
the odontoblasts into the middle of
the pulp-tissue, believing that den-
tinal canaliculi can only be formed
by odontoblasts. My observations
demonstrate that the odontoblasts
are nothing but medullary corpus-
cles arranged in rows. In the pres-
ent stage of our knowledge we have
no reason to assume that the medul-
lary corpuscles of the periphery of
the pulp are specitically destined for
the formation of dentine. It is just
as admissible to assume that the
blood-vessels in the pulp furnish a
certain variety of pabulum to the
medullary corpuscles, and under the
influence of this material they wall
be transformed into the tissue of
dentine. Should medullary corpus-
cles, in consequence of a slight irritation or an augmented afflux of nourish-
ing material, arise in the middle of the pulp, they may also produce dentine
or bone. The laws, however, which control the new formation of tissues
are as yet far from being understood.

History. G. Prochaska * first described that, when by attrition the teeth on
their upper surfaces are worn, there is within the pulp-chamber just as much
new material produced as there is worn away on the outer sm-face.

Rousseau t found " osteoids" and " bony gi-owths" in the pulp-cavity, but
states that Bertin has known this before him.

A. Nasmyth t says: "Much diversity of opinion has already existed
respecting the connection of the pulp with the ivory of the tooth, and as to

'^'^^^

Fig. 285. — Dentinifi CATION of the
Pulp.

FD, la3'er of piimarj' ileiitine; <S'7>, layer of
secondary dentine ; 0, laj-er of lamellated bone-
tissue ; O, granular laj-er toward the pulp-
tissue. Magnified 500 diameters.

* " Oper. Minor. Anat. Physiol, et Pathol. Arg." Pars, ii., Viennae, 1780.
t"Anat. Comp. du Syst. Bent. Chez 1' Homme et Chez les Princ. Auiniaux." Pari.s,
1827.

t " Researches on the Development, .Structure, and Diseases of the Teeth." 1849.

650 THE TEETH.

whether the ivory be simply a product of the pulp, or a transformation of its
substance." " The formative sm'face of the pulp displays a regular cellular
arrangement. The radiating rows of cells are surrounded by a well-defined
scalloped border, from which occasionally processes are observed to project
at regular intervals." This author also describes and illustrates several eases
of ossification of the pulp.

Kolliker * noticed new formations of dentine and cement on the walls of
the pulp-cavities of teeth.

L. S. Beale t maintains as follows : '' The tissue of the pulp, it must be
distinctly borne in mind, is not converted into dentine ; neither does dentine,
nor the tissue from which it is formed, exhibit any characters which justify us
classifying it with the connective tissues. I agree with Kolliker that the den-
tinal cells are the only active agents concerned in the formation of dentine,
but cannot regard the canals as direct processes of the whole dentinal cells, nor
admit that the matrix is an intercellular substance." " The mass of the pulp
is composed of a simple form of connective tissue, with numerous oval and
triangular corpuscles (germinal matter) not unlike that of which the mucous
tissue of the umbilical cord consists."

E. J. Hulme t gives a good description of the new formations in the pulp-
cavity. He names four varieties, viz. : secondary dentine, dentine of repair,
osteo-dentine, and nodular dentine, but he is of the opinion that the term
secondary dentine would suffice for all varieties.

E. Hohl § says that new formations of dentine are found within the soft
tissue of the pulp as well as on its periphery in connection with the pri-
mary dentine. The microscopical structure of these formations presents the
following deviations from normal dentine : the canalieuli run in all directions ;
now and then they enlarge like a sac, or terminate in large holes, which, how-
ever, ought not to be regarded as bone-corpuscles. Osteo-odontomes are
mixed formations, and show dentine in one and cement in another place.
Osteomata are found both free and adhering to the walls of the pulp-cavity.
The contents of the bone-cells, he believes, is a clear liquid, although in some
places it looks gi-anular.

Franz Boll 1| maintains as follows: "An examination of a specimen of
pulp-tissue by 500 diameters will exhibit, besides the numerous IneduUated
nerve-fibers, a large quantity of peculiar, silk-like, shining fibrillee, which
prove to be non-medullated nerve-fibers. The transition of medullated
into non-medullated nerve-fibers goes on quite gradually ; the latter at first
exhibit alternate expansions and constrictions in their diameters ; soon they
appear as naked, homogeneous axis-cylinders. The peripheral portion of
the pulp is composed of a continuous layer of elongated cells, which, by long
processes extending into the dentinal canalieuli, adliere to the dentine. If
this film adhering to the wall of the pulp-chamber is carefully scraped off
and brought under the microscope, we observe that it, besides the peripheral
cells, contains some portions of the pulp-tissue. In these we notice a large
number of non-medullated nerve-fibers, after teasing the specimen with fine
needles. Some of these course between the peripheral cells. Although I

* " Gewebelelire," iv., Aufl. t " On the Structure and Growth of the Tissues," 1865.

% "On Calcification of the Dental Pulp." Transactions of the College of Dentists of
England, 1861.

? " Ueber Neubildungen derZahnpulpe." Hallo, 1868.
II " Archiv. f. Mikroskop. Auatomie," vol. iv., 1868.

THE TKKTIl. 651

can furnish no direct proof, I consitlcr tlio prolongation of tho nerve-fibers
into the dentinal canalieuli as certain, the direction of the ends of the nerves
being parallel with the canalicnli. In the dentine near the pulp, we have,
therefore, to assume two varieties of canaliculi : those containing the proc-
esses of the peripheral cells of the pulp, and others, which receive the minute
nerve-fibers emanating between these cells."

J. Bruck, Jr.,* says that the structure of dentinal new formations is iden-
tical witli normal dentine, with the difference that in the former the canaliculi
assume a radiating arrangement and a wavy course. Such new formations
are found not only in carious, V)ut frequently in healthy, temporary and per-
manent teeth. He states that all formations which previously have been
described as depositions of lime-salts within the pulp are nothing else but
new formations of dentine. Dentinal tissue may develop not only from the
odontoblasts, but from any cell of the pulp-tissue.

John Tomes t asserts that the odontoblasts are in actual contact with one
another, and there is no room between them for an intercellular substance.
The most external portions of the odontoblasts undergo a metamorphosis into
a gelatigenous matrix, which is the seat of calcification, while their most cen-
tral portions remain soft and unaltered, as the fibrils. According to this view,
the fibril, the sheath, and the matrix are but three stages in the development
of the same tissue.

Carl Wedl j: says that the outer surface of the pulp is covered with conical
cells, — the odontoblasts, — from the broad faces of which, directed outward,
comparatively thick processes extend ; these enter the dentinal canals. The
basis-tissue of the pulp consists of a loose connective tissue. The greater
portion of the very common osteo-dentinal formations is eomfjosed of dentine ;
the bony substance occui's in a very small amount, and may consist merely of
a group of a few bone-corpuscles. With regard to the development of these
isolated, encysted new formations, Heider and I have maintained the view of
the occurrence of an inversion of the layer of dentinal cells. The calcareous
grains are true concrements, and occur in connection with hard new for-
mations, but never enter into organic union with the original dentine. They
are located within the parenchyma of the pulp, and are calcifications in the
connective tissue.

According to Waldeyer ^ on the odontoblasts, which are arranged so as to
form a kind of columnar epithelium, three kinds of processes may be distin-
guished : the dentinal process, the pulp process, and the lateral processes.
The first constitutes the dentinal fiber. The odontoblasts are intimately con-
nected with each other by means of fine, short teeth, which the lateral processes
of all dentinal cells form.

S. J. A. Salter II says: " A very pale, ill-defined, areolar tissue, pervaded
by numerous round and oval cells or nuclei, occupies the spaces between the
vessels and nerves. The cellular bodies toward the surface are enlarged and
assume the form of columnar epithelium. From their extremities project
minute tubular prolongations, which constitute the animal basis of the dentinal
tube-wall."

" " Bt-itriigc zur Histol. nnd Patliol. d. Zalmi)uli)e," Bresl.iu, 1871.

t "System of Dental Surgery," 1873.

t "The Piitliology of the Teeth," PhUadelphia, 1872.

'i "Manual of Hi.stology," by S. Strieker, New- York, 1872.

II "Dental Patliolo^j' ami Surgerj-," New- York, 1875.

652 THE TEETH.

C. S. Tomes* says: "The pulp may be described as being made up of
a mucoid, gelatinous matrix, containing cells in abundance, ■which are espe-
cially numerous near its periphery. In it some fibrous connective tissue is dis-
coverable. The odontoblast layer is sometimes called the membrana eboris.
The odontoblasts are furnished with three sets of processes," etc., like Wal-
deyer. " The exact natm-e of the terminations of the nei've-tibers is not
known."

Adolph Witzelt asserts that the odontoblasts, at their free extremities,
exhibit thick prolongations, and in their finely granular protoplasm contain
one or two nuclei. The new formations of dentine are composed of a finely
gi-anular or lamellated basis-substance, in which dentinal canaliculi are pres-
ent, etc.

The Pericementum. By C. F. W. Bodecker, D. D. S., M. D. S. t

(A) Forms and Dcvdopmcnt. The pericementum (root-membrane or alveolo-
dental periosteum, etc.) is a formation of connective tissue, identical with the
periosteum which covers all bones. It consists of a layer interposed between
the roots of the teeth and their corresponding bony alveoli, and is common to
both. It is continuous with the connective tissue — the so-called submucous
layer of the gum — and with the periosteum of the maxilla?. Its fibers are
connected with the cementum of the root as well as with the wall of the alve-
olus. A few WTiters have described the pericementum as a double membrane,
one of which belongs to the root, the other to the alveolus ; but I have not
been able to see anything that justifies such a separation. Only in a few
specimens have I seen, close around the root, a thin layer of very dense and
fine fibers, the general direction of which was not fully identical with that of
the connective tissue which produces the main mass of the pericementum.

The course taken by the connective-tissue bundles is slightly v^avj and
oblique, starting from the cementimi and ruiming upward toward the alveolus.
The bimdles of this tissue are very dense, without many decussations. The
parallel direction of the bundles begins to change into a diverging one at
about the height of the border of the socket, where the bundles become
coarser, decussate, and thus produce the elastic connective-tissue cushion
termed the gum.

From the anatomical disposition of the pericementum conclusions may be
drawn as to its physiological action. It is obvious that the relatively soft and
elastic layer between the two bony formations — cementum and alveolus — is
designed to lessen the concussion upon the jaw-bones during mastication.
The oblique direction of the connective-tissue bundles is the most favorable
for the suspension of the tooth within its socket, as the bundles correspond to
the fmmel shape of the socket, in the center of which is situated the conical
root of the tooth. The elasticity of the layer of jiericementiim admits of a
slight degi-ee of motion of the roots ; hence we understand the formation of
facets on the proximate surfaces of the crowns of the teeth in crowded maxil-
lary arches.

My specimens represent two varieties of pericementum — one of a reticu-

* "Manual of Dent.il Au.atoiiiy," Philiidelpliia, 1S76.

t " Pie autiseptisclie Beliaudliiug iler Pulpa-Kiauklieitcn," Berlin, 1879.
X Extracted from the essay, " Ou Periceiiientmn and Periceuientitis." The Dental Cosmos,
Philadelphia, 1879-80.

THE TEETH. 053

Inr structnro, termod myxomatous ; the other is altofic^tlier fibrous. The
myxomatous variety I liave met witii, as a rule, in younj^ individuals. It con-
sists of delicate fibers, or bundles of fibers in a net-like arrangement, which,
in many instances, are supplied with round or oblonf^ jiuclei at the points of
intersection. The meshes contain either a hyaline, ai)parently structureless,
sometimes finely fjranular, basis-snbstanco, or they hold plastids jn'ovided
with a varyinf? number of nuclei. The nearer to the cementum, the narrower
is the myxotuatous reticulum, aiid the smaller, therefore, are the inclosed ])las-
tids. The latter, in the immediate vicinity of the cementum, stand in more or
less regular rows, entirely analogous to the bioplasson bodies around the
developing bony tissue, known, since Gegenbaur, as "osteoblasts." Some of
the meshes of the myxomatous tissue are considerably larger, and contain
multinuclear bodies. Other meshes hold fat-globules, which, in specimens

r

'•r

Fig. 286. — Pericementum of Myxomatous Structure.

7), dentine; C, cementum of ueck ; P, pericementum ; jlf, multinuclear body ; T', capillary
blood-VL'Ksel; /', fat-globule with a vacuole. Magnified 500 diameters.

preserved and hardened in a solution of chromic acid, very often contain
closed spaces — so-called vacuoles. The myxomatous reticulum is traversed
by numerous blood-vessels, mainly capillaries and veins, some of which can
be seen entering the medullary spaces of the comj^act bone of the wall of the
alveolus and in connection with the capillary system of the cancellous portion
of the alveolus. I have met with but few nerve-fibers in my specimens. (See
Fig 28G.)

High amplification of the microscope plainly demonstrates the delicate,
reticular structure of all plastids, the reticulum being visible not only in the
contents of the meshes, but also within the fibers of the myxomatous reticu-
lum. The latter feature is recognizable best on specimens deeply stained

654 THE TEETH.

•with chloride of gold. The apparently structureless, or indistinctly granular,
myxomatous basis-substance, held in the meshes of the myxomatous reticu-
lum, proves to be a reticular structure, just as well as the bioplasson itself.

The second variety of pericementum is built up by fibrous connective
tissue, which prevails in adults and persons of advanced age. The bundles
of the fibrous connective tissue may be uniform in width throughout the
whole pei-icemeutum, or there exists a zone of myxomatous or indistinctly
fibrous character close around the cementum. The bundles are built up by a
number of fibers which hold a var\-ing amount of plastids — as a rule, more
numerous the nearer to the cementum. On the latter there may be found
rows of osteoblasts or scattered bioplasson bodies alternating with bundles of
a delicate connective tissue, which are directly attached to the cementum.
In a few instances I have seen rows of osteoblasts, the refracting power
of which was considerably augmented. Such corpuscles looked shining and
structureless, e\'idently on account of a deposition of lime-salts. The fibrous
variety of the pericementum also contains fat-globules, sometimes in a sur-
prisingly large quantity.

Higli magnif jing powers of the microscope reveal a structure of the fibrous
connective tissue, as follows : The fibers, a certain number of which combine
in the formation of a bundle, are delicate spindles, directly connected with
each other at their pointed ends. These spindles are separated from each
other by a nan'ow layer of a light cement-substance. The interstices between
the spindles are traversed in a vertical direction by extremely minute threads
every way analogous to the thorns in the cement-substance surrounding ei)i-
thelial elements. These threads, in many instances, are \isible in specimens
hardened by the chromic acid solution ; they become very plain when thin
sections have been immersed in a half per cent, solution of chloride of gold
for one or two hoiu's, or until the specimen has assumed a dark violet color.
If the stain be complete, we also recognize that the spindles are not homoge-
neous, as they look in fresh, unstained specimens, but are rather traversed by
a delicate, dark violet reticulum, the points of intersection of which are
slightly thickened, and thus represent granules. (See Fig. 287.)

Between the spindles of the basis-substance plastids are seen — the so-
called "connective-tissue cells." Some of these bodies exhibit shining, com-
pact, oblong nuclei, with a certain amount of surrounding bioplasson, while
others are devoid of nuclei, and split into spindle-shaped or polygonal lumps,
which in size and shape fully correspond to the elementary formations of the
fibrous basis-substance. In some instances, between the cementum and the
osteoblasts there is interposed a small layer of fibrous basis-substance in the
shape of delicate, slender spindles.

In its juvenile condition the pericementum represents a myxomatous
connective tissue, the fibrous portion of which is comparatively scanty, while
the bioplasson portion prevails. In this instance two varieties of basis-sub-
stance occur, viz. : the fibrous, building up the reticulum, and the myxo-
matous, filling a certain jjortion of the meshes. This condition arises from
the indifferent or embryonal tissue, not only in the pericementum, but in all
formations of connective tissue which, when fully developed, exhibit a fibrous
structiu'e. The only way to explain the formation of the mj-xomatous tissue
is, that a part of the substance constituting the embryonal elements remains
unchanged, a part is transformed into spindles of the myxomatous reticulum,
and a part into myxomatous basis-substance.

THE TEETH. f,.-,.-,

Tlio final result tnay bo, ospocially in poneoinontum, either a jelly-liko
luyxoniatous, or a solid, fil)rous basis-substance. The living portion, at all
events, remains untouclieil by the chemical alteration of the lifeless fluiil.

On this theory the transformation of the myxomatous tissue of juvenile into
tlie fibrous tissue of adult age is easily explicable. We only need assume a
dissolution or liquefaction of the already formed basis-suljstance in order
to understand the reappearance of the embryonal condition at a certain
stage of development. The myxomatous tissue as such never changes
directly into a fibrous one, but must first be reduced into its embryonal
or bioi)lasson condition, and from this in turn fi])rous connective tissue may
arise. The latter process is explained by the splitting and elongation of the
plnstids into spindles which become solidified ; in other words, the lifeless
fiuiil is transformed into a gluey basis-substance.

At no time has the reticulum of the living matter been interrupted or torn ;
the pericementum has never ceased to be a tissue either in its embryonal,

.~P^

-PL

Fig. 287. — Pericementum op Fibrous Structure.

C. cementum of root ; PL, pericementuiu, the fibers of which are built up by si)inrtles, in
lon^itiitliual section ; PF, pericementum, the elementary spindles of wliich are finer and cut
obliqui'ly ; pi, Pi, bioplasson bodies, either so-called connective-tissue corpuscles or so-
called osteoblasts. Magnified 1200 diameters.

mj-xomatous, or fibrous condition. On the theory here explained, all changes
in inflammatory processes of the pericementum may be easily understood.

(B) I'ericementitia. rimUc Inflammation and New Formation. Practitioners
are aware that pericementitis presents itself in two forms, evidently accord-
ing to the intensity of the inflammatory process. One form is the plastic,
which, if repeatedly recurring, leads to a new formation of connective tissue,
the so-called hyperplasia, or hypertrophy ; the other and more severe form
is the sitppurative pericementitis, which inevitably leads to a more or less
extensive destruction of the pericementum, to death of the pulp, and not
infrequently to necrosis of the alveolar process.

Pericementitis, in its mildest degree, with lower powers of the microscope,
is recognizable by the presence of nests, filled with medullary elements, in

656 THE TEETH.

the midst of the connective-tissue bundles. The shape of these nests is, as a
rule, oblong, corresponding to the longitudinal direction of the connective-
tissue biindles, or I'oundish, in accordance with the cross-section of bundles.
The scantier these nests, the milder is the inflammatory process. With high
magnifying powers of the microscope, we learn that the earliest stage of the
inflammation consists in a transformation of the connective-tissue fibers into
bioplasson. (See Fig. 288.)

According to the spindle shape of the elementary fields of the basis-sub-
stance, spindle-shaped bioplasson bodies have appeared, wholly identical with
the normal jjlastids within the fibrous connective tissue. All these bodies are
separated from each other by light rims, and connected with each other by

the delicate threads of living
fS^%y''\--yr^:m^^i^^^^^W^>^^^im matter traversing those rims.
" ' ' ;^^ The finely granular, newly

li^L • appeared bioplasson bodies

soon afterward become eoarse-

- ly granular, which means that

i'" • ' the living matter therein has

x^-.; yr ^ increased in size.

J^v^^J^^;: , , We see next that a number

; '""',?% - ■" of granules — the points of in-

■ V 1^ tersection of the reticulum —

have increased in size to such
; , ^^ an extent that they resemble

»<.»> v.:i-a,-i»- ,.,.„.», -4 ^ . .,^»::,.v. -:>-:^^.. /. , V asa? small nuclei, and from these

Fig. 288. — Inflamed Pericementum in an foci new elements are formed.
Early Stage. partly shining and homogen-

V, capillary blood-vessel, tlie euilotiielia of which eous, partly reticular in struc-
are coaiselj- granular aud proliferating; J/, medullary ture. After the originally solid
or inflammatory elements, imbedded in a finely lumps of li^"ino• matter have
granular basis-substance: <S', spindle shaped elements. ,., . , j- ■, n

Magnified 1000 diameters. split mto a reticulum, many of

the newly formed elements
contain solid nuclei. All elements are uninterruptedly connected with each
other by delicate threads of living matter. Thus, the inflammatory infiltra-
tion is established at first in the shape of scattered nests, the centers of
which correspond to the capillary blood-vessels. In later stages almost the
whole amount of the connective tissue is transformed into medullary ele-
ments to such a degree that only scanty bundles of the original connective
tissue are left. The swelling of the pericementum accounts for the painf ulness
of the process ; while the loss of the firm basis-substance and its replacement
by medullary elements explain the looseness of the tooth. These features
will also account for the peculiar sensation experienced by the patient that
the tooth is raised out of its socket.

The largest accumulation of the inflammatory elements takes place in the
immediate neighborhood of the blood-vessels, for in the middle of many nests
capillaries can be traced. We readily understand that in the immediate
%'icinity of the source of nutrition the inflammatory process must be most
active. This fact has been taken up as an argument by those who assert that
the inflammatory nests are altogether due to an emigration of colorless blood-
coi'puscles. I am strongly opposed to this opinion, because my observations
show that the majority of the inflammatory elements are originally connected

TIIK TKETII. 657

witli each other by delicate threads, tlierefore representing a tissue. The
endotheliii of tlie eapilhiries sliare in the intlaniinatioii by beinf? transformed
into coarsfly fjranuhir irrcfjuhir bodies, whicli, by division, also produce new
nu'<hdlary elfnients, i)artly nucleated, jmrtly devoid of nuclei. By the new
formation of inflammatory elements from the endothelia the caliber of the
ca]>ilhiry is first considerably narrowed and afterward completely lost. An
e.xuberant {growth of the endothelia will, as a rule, result in the destruction of
the capillaries by suppuration, and will probably give rise to formations
which I shall presently describe.

In most of my specimens of inflamed pericementum I have met with a
singular formation. A number of medullary corpuscles coalesce into gloVjular
masses, greatly varying in size, and in some instances surrounding a central
polyheilral space, evidently made by the compression of the former l)lood-
vessel. The globular masses are either composed of medullary elements,
shining, homogeneous, and split into smaller lumps of living matter, or they
are continuous masses of a coarsely granular bioplasson, in which varying
numbers of nuclei are seen. Fomiatious of this kind are well known in in-
flamed periosteum and medulla of bone ; they have been termed myeloj^laxes,
myeloid bodies, giant cells, etc.

My specimens plainly show that in the so-called plastic inflammation of
the pericementum all inflammatory corpuscles remain connected with each
other, and thus represent a medullary, embryonal, or indifferent tissue. In
slight degrees of inflammation the morbid process may yield to what has
been termed " the resolution of inflammation." Nothing is required but the
re-formation of the basis-substance, and the normal condition is reestablished.
More severe forms of plastic pericementitis, or repeated reciu'rences of the
inflammatory process, will result in a new formation of the connective tissue,
the so-called hyperplasia.

Higher degi-ees of i)lastic pericementitis are invariably accompanied by
inflammation of the gum, the cementum, and the bony alveolus.

Inflammation of the gum (ulitis, gingivitis) in its mildest form is marked
clinically bj' the so-called oedema. Higher degi'ees of ulitis manifest them-
selves in essentially the same manner as pericementitis, viz. : first, the forma-
tion of scattered, afterward confluent, nests of inflammatory corpuscles. The
origin of these nests from the connective-tissue bundles of the gum is exactly
the same as in the pericementum.

Cementitis is shown under the microscope by the presence of bay-like
excavations on the periphery of the cementum, and sometimes also beneath
the surface. These excavations are filled with medullary or multinuclear
bodies. To their presence is due the peculiar corroded appearance of the
cementum on teeth extracted during an attack of pericementitis.

Osteitis on the bone of the alveolus is manifested by a dissolution of the
basis-substance of the bony tissue, either in the shape of bay-like excava-
tions corresponding to the territories of the bone-tissue, or in irregular fields
tilled with medullary elements penetrating from the surface into the depth of
the bone. This process is invariably combined with osteomyelitis, and the
result of both processes is the transformation of the hard, bony tissue into a
soft medullary or inflammatory tissue. In some of my specimens of osteitis
this change is exhibited to a very high degree, so that only small islands of
bony tissue are left as remnants of the former wall of the alveolus.
42

658 THE TEETH.

Hyperj>Jasin. An intense plastic pericementitis, or repeated attacks of a
so-called subacute iuflaimnatory process, will lead to a new formation of con-
nective tissue, cementum, and bone.

Hyperplasia of pericementum occurs whenever a large number of inflam-
matory corpiiscles are newly formed and remain in connection with each other,
thus not ceasing to be a tissue. The inflammatory corpuscles in certain dis-
tricts become elongated, and, after having split into spindle-shaped elements,
are transformed into a solid basis-substance, which means a new formation
of connective-tissue bundles. These bundles differ from those of normal
pericementum in their greater density, and their very irregular arrangement.
Hypertropied cementum is augmented in its whole bulk, and is built up by
coarse bundles of connective tissue, between which, in the earlier stages of
the hyperplastic process, more or less numerous nests of inflammatory ele-
ments are seen. In other instances, the whole pericementum is transformed
into a dense cicatricial connective tissue, whose bundles are very small, and,
by crossing each other in all directions, produce a felt-work. Hyperplastic
pericementum, as a rule, holds fewer blood-vessels than the normal.

Sometimes scattered nests of the inflammatory coi'puscles take up a high
refracting power, which evidently is due to a deposition of lime-salts in them
— the so-called calcification. This process is entirely different from ossifica-
tion, though the former apparently precedes the latter. Scattered nests of
inflammatory elements may be transformed also into clusters of fat-granules.

New formation of cementum is observable in two forms : either as re-
formation in the bay-like excavations, or as a new formation on the outer
surface of the cementum.

Re-formation of the cementum is always characterized by a deposition
of lime-salts in the territories of the cement-corijuscles, previously dissolved
by the inflammatory process. The bay-like excavations remain unchanged
in their configuration, even after new cementum has formed. In the cemen-
tum of both the neck and the root I have met with such sharply circum-
scribed islands of newly formed cementum, apparently in no connection with
the outer surface.

The inflammatory new formation on the surface of the cementum appears
either in the shape of a continuous layer of cement-tissue, distinctly bounded
toward the normal cementum, or jagged on the outer surf ace, with manifold
elongations and erosions, filled with newly formed connective tissue. Some-
times relatively large globular formations appear on the outer sm-face of the
cementum as the result of pericementitis.

There are globular bodies in connection with the cementum by means of a
pedicle, which closely resemble those in the pulp-cavity attached to the den-
tine. These peculiar formations exhibit a distinct concentric lamination.
They are surrounded by a layer of spindle-shaped medullary elements, and
hold in their centers a radiating bioplasson mass, resembling a bone-corpus-
cle. As to their origin, there can be scarcely any doubt that they arise from
clusters of medullary or multinuelear bodies, above described. All new for-
mations on the surface of the cementum, caused by an inflammatory process,
may be justly denominated "exostoses of the cementum." (See Fig. 289.)

I have repeatedly seen true bony new formations in hyperplastic perice-
mentum. They appear in the shape of irregular islands or elongated spicula;
within the fibrous connective tissue, sometimes so near to the cementum that
no doubt is left about their formation in the middle of the pericementum,

Till': TEKTII. 659

indopendontly of the bony alveolus. Tiiose formations bear a close resein-
lilaiice to embryonal bone — viz.: contain a larjje number of irregular bone-
eor])uscles witli broatl otTshoots, and a comparatively small amount of bony
basis-substance. On the i>eriphery of isolated bony formations we can often
distin^'uish the medvdlary elements (osteolilasts), which jjarticipate in the
formation of bone by bein<; i>artly transformed into basis-substance.

Lastly, true bony new formations may occur on the wall of the alveolus,
which, after rei)eated attacks of pericementitis, as clinical o})servation
teaches, is sometimes beset with thorny new formations of l)one. These
exostoses originate on the socket of the tooth from the medidlary tissue, in
the same manner in which exostoses grow on any other bone, as sequela^ of
periostitis ami osteitis. In the highest degree of development, such exostoses
of the socket replace the pericementum to such au extent that only traces
of the pericementum are left. No instance, however, at least to my knowl-
edge, has been observed of a complete fusion of the socket with the tooth.

I'ljorrhcea Alreolaris. Surgeons have long been aware of the fact that sup-
purative periostitis is the main, if not the only cause of necrosis of bone ;

n

^4

Fig. l'SO. — Glubulau Body, Kesult of Pekiceaientitis.

G, concentrically striated mass, surrounded by small, si)iiidle-sliaped elements, lioldinjr a
star-sliaped bioplassou bodj- in its center; (', cementum : ^r, nmltinnelear bod.v, from wlilch
a frlobular body may originate; J'-B, iutlammator3- elements, crowded in tlie i)ericenientum.
Ma^'iiified 200 diameters.

thus, also, the consequence of suppurative pericementitis is necrosis of the
alveolus, varying in accordance with the degree of the suppuration. No ciu-e
of the suppuration is possible until the necrotic parts of the bone have been
eliminated from the body, either spontaneously or by stu-gical interference.

Under the microscope, the first stages of suppiu-ative pericementitis are
identical with those of the plastic form — v-iz. : there are nests of inflammatory
corpuscles between bundles of unchanged connective tissue. The less, there-
fore, of this connective tissue is left, the more numerous the inflammatory
elements are, the nearer is the tissue to suppm-ation.

6G0 THE TEETH.

With high magnifying powers of the microscope we see that the inflamma-
tory process goes on in exactly the same way as in plastic pericementitis.
The bundles of connective tissue are transformed directly into inflammatory
corpuscles, which at first are all united with each other. This union is recog-
nizable in relatively large nests, also, in which there are Vmt scanty capillar^'
blood-vessels left. It is only after the mutual connection of these elements is
broken that the bodies, now isolated, deserve the name of pus-corpuscles,
which are suspended in an albuminous fluid, and fill a cavity termed an
"abscess." K a large number of inflammatory centers, which afterward
become confluent all around the root of the tooth, have formed, we designate
the disease "alveolar pyorrhoea."

In some of my specimens, among the inflammatory elements, there are
seen capillary blood-vessels, containing a few colorless blood-corpuscles, some
of which, by means of a slender pedicle, have penetrated the wall of the cap-
illary, and are evidently engaged in emigration. These colorless blood-
corpuscles, however, are finely granular, and, as such, easily distinguishable
from the surroimding inflammatory corpuscles, the vast majority of which are
coarsely granular or homogeneous. Emigrated colorless blood-corpuscles may
share in the formation of pus-corpuscles, but the main mass of the latter
is doubtless formed directly from the connective-tissue substratum of the
inflamed part.

After the elimination of the pus the surrounding inflamed tissue grows in
the shape of so-called "proud flesh" or gi-anulations, which we not infre-
quently meet on the roots of teeth extracted during an attack of suppurative
pericementitis, especially well developed in the bifurcations between the roots
of molars. Such granulations are built up by a myxomatous connective tissue,
which is freely vascularized, and, after having filled the ca^^ty of the abscess,
is transformed into a dense, fibrous connective tissue. This reparative tissue
is termed a "cicatrix." Suppurative pericementitis will invariably heal by
cicatrization.

Alveolar Abscess. This is a peculiar form of suppurative inflammation
on the apices of the roots of teeth.

Examinations of microscopical sections through the root, the socket, and
the alveolar abscess, demonstrate that the latter is either unilocular or
multilocular, viz. : separated into two or several chambers, all filled with
pus. The wall of the abscess is built up by a very dense fibrous connective
tissue, the bimdles of which mainly run a concentric course around the
abscess, and are continuous with the unchanged or slightly inflamed peri-
cementum higher up on the root. The sac is a product of plastic pericementitis,
fully identical with what has been termed in former years the " membrana
pyogena." ^Tien the inflammatory process has lasted for months, the newly
formed connective tissue assumes a distinct fibrous structure, and between
the bundles there are interspersed nests of inflammatory corpuscles. These
may be partly transformed into fat-granules, or produce opaque layers in fatty
degeneration. If, on the contrary, the alveolar abscess be of a more recent
date, the fibrous structure of the sac is plainly marked on its periphery only,
while the central portions bear the character of a my.xomatous granulation-
tissue. The strings or the septa traversing the abscess may, in accordance
with the age of the disease, be found either of a fibrous or mj-xomatous
structure. In both instances we often meet with a large number of newly
formed capillary blood-vessels. The inner surface of the sac is not smooth,

THE lEETll. 661

Imt lurfjcly pi-Dvidcd witli irrcfjiihir i)rotru8ions, or papillary outgrowths of
a myxomatous structure, crowded with iiitlammatory cUnneiita. The sac
contains inspissated pus, wliii-h, upon tiie cuttiiit; of microscopical sections,
crumbles away.

CenuMititis and osteitis always accompany an alveolar abscess. Cementitis
leads to a destruction of the cementum in the shape of deep, irregular, bay-
like excavations, which exhibit all stages, from the liquefaction of the basis-
substance up to the trausfornuition of the living matter into pus-corpuscles.
Sometimes the excavations penetrate the dentine. In the highest degrees of
pericementitis the apex of the root, inclosed in the alveolar abscess, is trans-
formed into a thin, jagged, and corroded stump, with but scanty remnants of
the former cementum.

Osteitis (inflammation of the wall of the alveolus) is anine^^table result of
the formation of an alveolar abscess. The portion of the socket in contact
with the sac of the abscess is widened, its surface being either smooth or
jagged. Examination with the microscope leaves no doubt that the inflamma-
tory elements, sprung from the bony tissue after dissolution of its lime-salts
and liquefaction of its gluey basis-substance, become spindle-shaped, and
participate largely in the formation of the wall of the abscess.

Litcrutitrc. In regard to the literatm*e of pericementum and pericementitis
I have but little to say, as this subject has been very much neglected by
nearly all histologists. I shall quote from a few only of the modern authors.
Carl Wedl * says : ' ' Generally the root-membrane, or periosteum of the
root, is of moderate density ; the bundles of connective tissue forming it con-
tain no elastic fibers, and inclose fusiform connective-tissue corpuscles ; in
addition to these, roundish elementary organs are met with."

According to E. Magitot,t " the root-membrane consists of two portions:
an inner, which does not admit of being teased into fibrils ; and an outer, Ijing
near the alveolar wall, which has the appearance of a fibrous structm*e. The
same wi-iter also mentions the occurrence of ' cellules myeloplaxes,' similar
to those found in the periosteum of bone, and cytoblastions (nuclei invested
with a layer of protoplasm), which occur still more rarely." " The changes
in the hard tissues of the root, which occui- chiefly with chronic suppm-ating
inflammation of the periosteum of the root, consist in necrosis and resorption,
according to the nature of the tissue." "The histological appearances pro-
duced by the process of resorption are displayed in a manner similar to those
which were observed in the resorption of the roots of the milk-teeth — /. e.,
there are circumscribed depressions upon the outer surface of the cement,
which are made up of gi-oups of closely approximated, shallow, cup-shaped
indentations. In the ridge-like elevations which bound the excavations well-
preserved bone-corpuscles are to be found, while they become gradually less
discernible in the deeper portions. Necrosis of the cement not infrequently
is associated with resorption." "If the cement is entirely destroyed here and
there by the suppuration, the dentine becomes similarly ailected, and acquii-es
a roughened or corroded appearance." " There are no indications of a vital
action on the part of the dentine. The theories advanced to explain the
manner in which the excavations are produced by resorption are mere sup-
positious ; they may be regarded as induced either by the activity of the pus-

* '• Pathology of the Teeth," Philadelphia, 1872. Page 59.
t " Menioires sur les Tumeurs clu Perioste Dentaire." 1868.

662 THE TEETH.

corpuscles, or l)y a fermentation jirocess ; with regard to tlie former, it is
conceivable that the amoeboid movements of the pus-corpuscles might wear
away the dental substances ; in the latter case, the generation of au organic
acid might be assumed. In chronic cases, the eroded portions are covered by
a thin membrane of connective tissue or by a layer of gi-auulation tissue."
" Sometimes, on the other hand, the inflammation spreads from the root-mem-
brane to the socket of the tooth; when this occurs, the canals of the latter in
the vicinity of the focus of suppuration become expanded; excavations, in the
form of pits and grooves, are found in it, and, finally, there ensues a partial
resorption of the alveolus, which process is induced by the proliferation of
the elementary organs of the connective tissue." ''In addition to the senile
form, a hypertrophy occurs as a sequel of chronic affections -of the root-
membrane, consisting essentially in a thickening, and a more or less
advanced callous formation. The generally straight bundles of fibrous tissue
often pursue a radiating course for the most i)art — /. c, they extend from the
outer surface of the cementum toward the alveolar wall, forming a series of
closely packed arches, and are inserted, by a fan-shaped expansion, into the
osseous trabeculffi." "The bundles of connective tissue, especially in cases of
very irregular h^^pertrojjhy, interlace one with another in various directions,
forming a sort of felted work of bundles, which penetrate the enlarged fora-
mina in the alveolar wall.

Charles S. Tomes * says : " The general direction of the fibers (of the alve-
olo-dental membrane) is transverse — that is to say, they run across fi-om the
alveolus to the cementum without break of continuity, as do also many capil-
lary vessels; a mere inspection of the connective-tissue bundles, as seen in a
transvei'se section of a decalcified tooth in its socket, will suffice to demon-
strate that there is but a single ' membrane,' and that no such thing as a
membrane proper to the root and another proper to the alveolus can be tlis-
tinguished. At that part which is nearest to the bone the fibers are gi'ouped
together into conspicuous bundles; it is, in fact, much like any ordinary
fibrous membrane. On its inner aspect, where it becomes continuous with
the cementum, it consists of a fine net-work of interlacing bands, many of
which lose themselves in the surface of the cementum. But, although there is
a marked difference in histological character between the extreme parts of the
membrane, yet the markedly fibrous elements of the outer blend and pass
insensibly into the bands of the fine net-work of the inner part, and there is
no break of continuity whatever. I have never seen the fibers, whether
in longitudinal or in transverse sections, pass straight in the shortest possible
line from the bone to the cementum, but they invariably pursue an oblique
course, which probably serves to allow for slight mobility of the tooth with-
out the fibers being stretched or torn."

liesults. The results of my researches may be summed up in the following
points :

(1) Pericementum Is a layer of conucciire tissue between the root of the tooth
and the wall of the alveolus, and common to both. This connective tissue in the
juvenile condition is mi/xowatous, rich in biojilasson bodies. In the adult it is
fibrous, scantily supplied with 2)lastids — the so-called connective-tissue cell^. The
bundles of the connective tissue are continuous with those of the gum and those of
the periosteum of the alveolus.

* "A Manual of Deutal Auatomj'," Pliiladelphia, 1876.

77//<; TKETH. 003

(2) Inflammation of the pericementum i.s either a plastic (formative) or siijt-
puratire (destrnctire) process. These two kinds difer from each other only in
dcffrec and intensity.

(8) Plastic pericementitis is characterized hy the formation of nests of injlani-
matory elements, arisen from medullary elements which hare appeared from the
connectire tissue after dissolution of its basis-substance.

(4) Plastic pericementitis may terminate in resolution, if the inflammatory
elements be not numerous, and the basis-substance be reestablished ; or it leads to
hyp<rplasia of the connectire tissue, if a large number of inflammatory elements
hare formed and the inflammatory process has repeatedly recurred.

(5) Pericementitis in its more intense degrees is always accompanied by
cementitis of the root of the tooth, and by osteitis of the wall of the alreolus.
Plastic jiericemcntitis leads to a new formation of cementum, as well as of bone-
exostosis.

((.)) Suppuratire pericementitis results from the breaking ajiart of the inflam-
matory corpuscles which hare arisen from the connectire tissue of the pericementum-
itself. Emigrated colorless blood-corpuscles probably share in the formation of
pus-corpuscles ; but no proof thereof is possible. The main mass of pus-corpuscles
is due to a transformation and destruction of the inflamed tissue.

Caries. By Frank Abbott, M. D.*

Methods. The results recently obtained with regard to the minute structure
of the teeth have been aiTived at by new methods. As a matter of com-se,
dried specimens of teeth, formerly almost exclusively in use, did not reveal
any of the soft parts -within the hard dental tissues. Only a frame of the tissue
was left, and we may readily understand why the investigations of the carious
process as yet have not passed above hj^potheses and speculations.

For preparing dentine and cement, there is no better method knowTi than
slow decalcification by means of a one per cent, solution of chromic acid. The
enamel of teeth prepared in the foregoing manner can never be cut, because
it becomes extremely brittle ; therefore, I was obliged to resort for its exami-
nation to the method first practiced by Dr. Biklecker. The thin slices should
be kept for decalcification, for twenty-fom- hours, in a very dilute solution of
chromic acid. A saturation of this solution of over one-half of one per cent.,
in my opinion, is deleterious to the enamel, which, if completely decalcified,
shows only a minute net-work of liring matter, as I tii'st have observed, but no
trace of the enamel-rods and prisms.

Caries of Enamel.] The clinical phenomenon of caries, in its very origin,
consists essentially in a discoloration of the enamel. A whitish or gra.\ish
spot on the surface of the enamel is indicative, to an experienced eye, of the
beginning of decay, which spot proves, when touched with an instrument, to
be soft and crumbly. Often a brown spot is visible on the enamel as a sign
of the softening process. The less pigmentation present, the more rapid
is the process of decay. On the contrary, the more distinct the diseol-

* Abstract from the author's essay, "Caries of Human Teeth." The Dental Cosmos, Phil-
aileliihia, 1878 ami 1879.

t The fact tliat caries of the teeth bejrins as a chemical i)rocess scarcelj- will, in my opin-
ion, be questiuneti. On a dead tooth, natural or artiticial. as well as ou teeth manufactured
from the dentine of the elephant or the hippopotamus, the process will remain, under all cir-
cumstances, a cliemical one, assisted only by the putrefyius; remains of the organic material
of the tooth ; while ou a live tooth either acute or chronic reaction-changes take place.

664

THE TEETH.

oration, the slower is the softening process. Nay, dark-brown spots maybe
present in the enamel for many years without l)eing followed by softening.
The brown discoloration, as such, cannot be considered as an essential feature
of caries of enamel, but it usually accompanies the carious process, and does
so the surer, the slower the morbid process runs. On microscopic specimens
we meet with decayed pits in enamel without auy discoloration of this tissue.
On other specimens we have a very marked orange or brown hue on the
decayed part as well as in its neighborhood, and sometimes scattered specks
are to be seen some considerable distance from the diseased part. The brown
discoloration is located in the basis-substance of the enamel-rods, the outlines
of which are much more marked than when in a healthy condition. The
interstices between the rods here are plainly visible even with a magnifying
power of only five hundred diameters. This power will reveal delicate beaded
fibers of living matter within the interstices, which in healthy enamel can be
seen distinctly with a power of eight hundred to one thousand only. Besides
the discoloration, no material changes are seen on the enamel-rods.

Fig. 290. — Acute Caries of Enamel.

E, unchanged enamel ; H, enamel deprived of its lime-salts ; il/, enamel broken down to
medullary corpuscles ; I), medullary corpuscles, indistinctly marked ; N, flat epitlielia.
Magnified 1000 diameters.

The process of decay in the enamel can best be studied on superficial ero-
sions of the same, a sample of which I have illustrated. In this instance the
brown discoloration of the decayed part was but trifling, and entirely absent
in its vicinity, so that we have to consider it as a case of acute caries. Not a
trace of micrococci or of leptothrix is visible in or above the decayed pit of
the enamel, which again proves that these organisms do not play any important
part in the process of caries. (See Fig. 290.)

The shape in which caries appears in the enamel is greatly varying. Be-
sides the wedge shape, the forms in which caries proceeds are shallow or con-
ical excavations, excavations with abrupt walls, fissures, and grooves. On the

THE TEETH. 665

bottom of the main oxeavatioii wo somotimossee a smallor cavity, itbeiiif^ in
a narrow or wi<U> oommiuilcatioii witli Mic main (Ici-ayfl mass.

Bi'sides the peculiar metluiliirv elements forming tlie contents of a carious
cavity of the enamel in its initial staf^e, I not very rarely have met with dark
brown, irregularly shaped clusters (iliiiiffthe whole cavity. How such changes
of medullary corpuscles are jiroduced I am unable to say, although it seems
to be kindred to the so-called colloid or lii/oloid metaTnorj)hosis which we
observe in other tissues, the only difference being that in caries the colloid
clusters are deeply saturated with a uniform l)rown pigment.

('(trii's of Driitiiic. Sometimes the dentine, attacked by caries, looks but
little changed on its ])eriphery. A narrow zone of yellowish color forms the
boundary toward irregular, shallow excavations. At other times, Ijcsides the
bay-like excavations on the periphery, there are visible elongations, cylindri-
cal, conical, pear-shaped, or leaf-like, passing down into the dentine in vary-
ing depths. There is no doubt that this form of decay of the dentine occurs
with the least preliminary changes of the tissues; it evidently runs a slow
course, and I think I am justified in calling this form of caries clironie. It
seems e\'ident that decay of a tooth assumes an acute or chronic form just
in proportion to its perfect or imperfect calcification. Dead teeth in which

Vt {: \':y<' }''f^^r!^^^^-T^v^\f7:-\^ .

Fig. 291. — Chronic Caries of Dentine.

D, dentine ; O, the process of decay penetrating into the dentine in the shape of sliort
oflfslioots ; C, decayed mass. Maguilied 200 diameters.

the pulps have been destroyed either by necrosis as a natural process, or by
artificial means with caustics, very frequently run this kind of slow or chronic
decay. (See Fig. 291.)

I have examined a piece of a hippopotamus tooth which for a period of
about one year was v/orn in the mouth of a patient, and a spot became
decayed about the size of a hemp-seed. On the bottom of the decayed pit
numerous conical spots appeared running downward into the dentine,
characterized by the absence of coloring matter in specimens stained with
carmine. No material change besides was observable ; even the dentinal
canaliculi did not look enlarged. The bottom of the carious cavity was
covered vnih a layer of finely granular, evidently disintegrated organic
material, and above this the ordinary masses filling carious ea\'ities in teeth,
viz. : micrococci and leptothrix, were visible.

In chronic caries first the solution of the lime-salts of the dentine takes
place, either along the bay-like excavations or in the shape of longitudinal

666 THE TEETH.

depressions. No reaction whatever follows tliis process. The glue-yielding
basis-substanee being deprived of its lime-salts, shows a yellow discolora-
tion, and only traces of the dentinal canaliculi. The basis-substance then
breaks down into an indistinct gi-anular mass, which is immediately filled
with a new growth of low vegetable organisms, viz. : micrococci and
leptothrix.

My specimens plainly show that these organisms are not the adi-ance-
(juard in the process of decay. The fii"st change that takes places is expos-
ure of the basis-substanee by the chemical action of some acid, independent
of the named organisms, which come to view only after complete disinte-
gration of the basis-substance. I never have seen the penetration of these
organisms into the dentinal canaliculi before a thorough decalcification of
the basis-substance had taken place.

In. the great majority of my specimens I have met with formations on the
diseased boimdary of the dentine which demonstrate a considerable degree

I

Fig. 292.— Acute Caries op Dentine.

E, E, fissures in whicli the decay penetrates into the dentine ; I, small islands of un-
changed dentine. Magnified 200 diameters.

of reaction, produced by the irritating power of the same agent to which
the lime-salts of the dentine yield. In fact, this was the case in all teeth
which were alive when attacked by the carious process, or rather when
removed from the jaws. On the boundary of this process we see irregularly
shaped elongations running a certain depth into the tissue of the dentine.
The more superficial the elongations are, the surer the morbid process
may be termed a slow one ; and. on the contrary, the deeper the elongations,
the more certain we may be that the morbid process lias advanced rapidly.
The elongations mainly have the shape of fissm-es filled with a dark, granidar
material, if \dewed with a low power. These fissures run independently of the
direction of the dentinal canaliculi ; nay, very often cross them. (See Fig. 292.)
On the sm-face of the carious portion of dentine we see irregular ca%'ities.

'/•///•; Th'h'ni. (iO?

fillcil with the same Kraiiuliir mass tliat is pri-soiit in tho fissures, consisting
ovi.icntly of (U'-bris of tlic former tissue, tot,'etlier, i)erhai)S, with micrococci,
and very often tine, tlirea<l-like ieptothrix. Tlie more ra])i(lly tlie .lestructiou
of tlie dentine has advancecl, tlie more irrcKular islands of dentine are left on
tlie surface.

The outermost portion of the decayed part is, as a rule, brittle, and cnun-
bles away in chronnc acid si)ecimens. Where it is left it shows a crowd of
lei)tothrix and micrococci, without any distinctly recof,M\izable remnants of the
fornuu- tissue. On the boundary of the carious portion we, as mentioned
above, meet with a yellow discoloration of the dentiiu-, evidently produced by
a chemical agent, wliich first dissolves out the lime-salts from the dentine,
ajid in turn li(iuefies the glue-yielding basis-substance. In live teeth the yel-

m

Fig. 293.— Caries of Dentine.

F, iinclianged dentinal fiber: P, enlarged dentinal caualiculi, filled with liioplasson ; If^
medu'uarj- corpuscles in considerably widened dentinal spaces ; G, complete trausformatiou
of dentine into medullary corpuscles. Magnified 1000 diauieters.

low discoloration usually takes place in the shape of longitudinal strings of
different diameters, running mainly parallel with the longitudinal direction of
the dentinal canaliculi. Nay, we often see single yellow strings running from
the bottom of a carious cavity in the enamel through the whole depth of the
dentine to the pulp-chambers. While the unchanged dentine readily takes up
the carmine, the strings, the deep yellow color of which is undoubtedly due to
the action of the chromic acid, remain unstained. (See Fig. 292.)

668 THE TEETH.

We recognize, under the microscope, in longitudinal section of the dentine,
that sometimes the yellow discoloration has taken place only within the lim-
its of a few dentinal canaliculi, while at other times quite a number of these
have undergone discoloration. Still sharper defined is the yellow discoloration
on transverse sections. Here we see that mainly the canaliculi and their
immetliate neighborhood have taken up the yellow color in the shape of
sharply circumscribed dots, which are the larger the nearer they approach to
the periphery- of the decayed part. The basis-substance between these yellow
spots has taken up more or less carmine. (See Fig. 293.)

At a certain distance fi-om the decay the canaliculi look imehanged. and
each contains the central transverse section of the dentinal fiber, with its del-
icate radiated offshoots. Nearer to the decay we meet with moderately

El!^S^:'^''P'

m:-

wrn^

:U

I -■. _:^.~L.^.. ....-> OF DEXTi:>i:,. Ui^lique Section.

P, wifieued dentinal canaliculus, containing bioplasson ; A', space containing medullary
corpuscles : M, transformation of dentine into bioplasson ; C, trace of dentinal canaliculus
containing an enlarged fibril. Magnified 1000 diameters.

enlarged canaliculi, the center of which is occupied by a cluster of bioplasson,
the granules and threads of which have readily taken up the carmine. One
step farther we tbid the canaliculi considerably enlarged — to double or treble
their original size — and they are filled mth bioplasson, plainly exhibiting the
net-like arrangement of the li%-ing matter. The most peripheral grauides send
delicate conical offshoots through the surrounding light space toward the
imehanged basis-substance. In some of the enlarged canaliculi accimiula-
tions of living matter are seen fully in the shape of nuclei ; sometimes two or
more such nuclei may be seen surrounded by a varying amoimt of granular

TIIK TKKTII. 6G9

bioplasson. Still nearer to the fleeay the eiinaliciili are eiilar^o'l to ten or fif-
teen times their orij^iiial diameter, and the cavities thns produced are all
filled with a i)artly nucleated bioplasson. Between the roundish cavities we
meet witii lonf^itudinal cavities, arising from the confluence of several cavi-
ties in one main direction. The cavities continue increasing in size, and form
large spaces, with rouiuled, bay-like boundaries, between which only scanty
traces of unchanged basis-substance are left. Lastly, the basis-substance has
entirely disappeared, and only biojilasson is visible in its place, either in the
shape of multinuclear layers or of iiTegular so-called medullary elements,
with rather faint marks of division. Nearest to the periphery the bioplasson
does not exhibit any form-elements, but looks like a disintegrated granular
mass, probably intermixed with or replaced by micrococci.

In less acute caries a relatively small number of dentinal canaliculi are
enlarged and filled with bioplasson. The center of the bioplasson bodies is
occupied by one or two nuclei, which look as if they originated from the
former dentinal fiber. On the periphery of the dentine there are regular
nests filled with bioplasson formations of the above description, partly V>roken
down into medullary elements. On other parts, on the contrary, the transfor-
mation of the basis-substance into bioplasson has even preceded the changes
of the dentinal fibers. The canaliculi are not noticeably enlarged ; the den-
tinal fibers are either unchanged or slightly swollen, and more gi-aimlar than
in the normal condition ; while outside these we have a thoroughly decalcified
and liquefied basis-substance, which means a reappearance of the net-work
of the living matter before the stage of disintegi-ation. (See Fig. 294.)

Caries of ('eme)it. So long as the gums are in their normal condition and
position caries does not begin in the cement; but, if the gums have receded
fi'om any cause, thus exposing the cement which covers the necks of the
teeth, it may then begin to decay. The microscope reveals a more or less
advanced decay, which, in its essential featui'es, is fully analogous to caries
of the dentine when in a live condition. On the boundary of the caries we
see, besides unchanged cement-corpuscles, those which have been enlarged
and transformed into medullary or inilammatory elements. Nay, I have
observed that the lacunae holding the bioplasson body were partly unchanged
while a part participated in the inflammatory process. (See Fig. 295.)

The enlargement of the cement-corpuscles is evidently not due to their
direct swelling, but to a liquefaction of the surrounding basis-substance, in
which the bioplasson condition, and with this also the medullary elements
which have participated in the formation of the basis-substance, reappear.
The inflamed portions of the cement look granular with lower powers of the
microscope, but high powers reveal the net-like structure of the living matter
and the formation of irregular polyhedral elements, which are separated from
each other by a light, narrow seam, this being traversed by extremely delicate
uniting threads.

Virehow's view that the bone-coi-puscles swell and divide into inflammatory
elements by being converted into proliferating mother-cells, is in my opinion
wrong. No proliferation is demonstrable in the earliest stages of inflamma-
tion of the cement. Nothing but a decalcification, and thereafter a liquefac-
tion, of the glue-yielding basis-substance takes place in order to bi"ing to view
the very same medullary elements which once have shared in the formation
of the cement. The inflammatory reaction in the cement-corpuscle itself may
be so slight that a part of this bioplasson may look almost unchanged, while

670 . THE TEETH.

another part toward the decalcified basis-substance gives an appearance iden-
tical with that of the surrounding liquefied basis-substance. The result of
this process is a transformation of the tissue of the cement into medullary
or inflammatory elements. These remain in connection with each other by
delicate threads of living matter, but at last become disintegi'ated, and give,
together with micrococci and leptotlu-ix threads, a decayed mass, just as well
as enamel and dentine.

BesuUs. I can sum up the results of my researches in the following
aphorisms :

(1) In enamel, caries in its earliest staf/e is a chemical process. After the lime-
salts are dissolved out, and the iasis-suhstaiice liquefied, the hioplasson reappears,
and breaks apart into small, irregularly shctpcd so-called medullar)/ or enihnjonal
bodies.

(2) Caries of dentine consists in a decalcification, and in turn a dissolution,

w

W

I

r

■^

Fig. 29.5. — Cemextitis Due to Caries.

C, iinchangetl cement-conniscle: I, space filled with medullaiy corpuscles; P, cenieut-
•corpuscle, i)artl}' unchanged, i)artly transformed Into medullary corpuscles; M, the ccmen-
tnm wholly transformed into medullary corijuscles. Magnified 1000 diameters.

of the f/lue-i/ieldinff basis-suhstance, around the canaliculi as well as between
them. The liring matter contained in the canaliculi is transformed into nucleated
hioplasson bodies, which, iof/ether with bodies ori</inatin<j from the liring matter
in the basis-substance, form the so-called indifferent or infiammatory tissue.

(3) Cement, if attacked by caries, exhibits first all phenomena known to be
present in the early stages of inflammation of bone. The cement-corpuscles, as
well as the basis-substance after its decalcification and liquefaction, produce
indifferent or inflammatory elements.

riiK TFJ'/ni. G71

(4) The iiidiffcrnit rlniinits orKjinittiiKj tlir<>ii(/li llir carious procrss from
enniiicl, dcuthir, tnul cniinit do not firorvcd in iicir fornittlioii of Uriiiij niaftcr, hut
hcconir disiiili<ir(ilrtl (did tniusftnitrd into (( moss crowded n-illi niicrorocri and
Icplotlirix.

(5) Varies of a lirin;/ tooth, therefore, is an inflainiiiatorif process, which,
hetjinniiui as a chemical process, in turn reduces the tissues of the tooth into
embryonic or medullarj/ elements, erideutli/ the same as during the develojiment
of the tooth hare shared in its formation ; and its derelopment and iutensiti/ are
in direct proportion to the amount of lirint/ matter which they contain, as com-
pared with other tissues.

(()) The medullary elements, owiuf/ to lack of nutrition and to continuous
irritation, become necrosed, and the seat of an actire new fjrowth of organisms
common to all decomposing organic material.

(7) Micrococci and leptothrix by no means produce caries ; they do not pene-
trate the cavities in the basis-substance of the tissues of the tooth, but appear only
as secondary formations, owing to the decay of the medullary elements.

(S) In dead and artificial teeth, caries is a chemical process, assisted only hy
the decomposition of the glue-yielding basis-substance of dentine and cement.

History. John Hunter* says: "The most common disease to which the
teeth are exposed is such a decay as would appear to deserve the name of
mortification. But there is something more, for the simple death of the part
would produce but little effect, as we find that teeth are not subject to
putrefaction after death, and therefore I am apt to suspect that during life
there is some operation going on which produces a change in the diseased
part."

Joseph Foxt says: "The diseases to which the teeth are subject are simi-
lar to those which affect bones in general, and in like manner they have their
origin in inflammation. The teeth differ only from bones in not possessing
sufficient living power to effect the process of exfoliation."

Thomas Bell,t under the heading of "Gangrene of the Teeth, commonly
called Caries," says: "The most common disease to which the teeth are
liable is that which has hitherto been universally known under the name of
caries— a, name which, although authorized both by English and Continental
writers, is in this instance totally misapplied. It is, in fact, calculated essen-
tially to mislead, as the disease has not the slightest analogy to true caries of
bone." "Still, however, the true proximate cause of dental gangrene is
inflammation. That the bony structure of the teeth is liable to inflammation
appears not only from the identity of the symptoms which take place in them,
when exposed to causes likely to produce it, with those which are observed
in the other bones when inflamed, but more conclusively still from the fact,
already mentioned, that teeth are occasionally found in which distinct patches,
injected with the red particles of blood, have been produced by this cause
after the continuance of severe pain."

Dr. E. Magitot,? in his general conclusions, says: "Dental caries is a
purely chemical alteration of the enamel and ivory of the teeth. Lesions of
the enamel consist, after the removal of the cuticle, in a purely passive
chemical disorganization of the prisms composing its tissue. Lesions of the

* " Diseases of the Teetli," etc., 1778.

t " The History and Treatmeut of the Diseases of the Teeth and Gums," 1806.

t " Anatomy, Physiology, aud Diseases of Teeth," 18:^1.

i " Treatise on Dental Caries" (English translation hy Dr. T. II. Chandler, 1878).

672 THE TEETH.

ivory, consisting likewise in a chemical decomposition of its elements, may
sometimes, though rarely, remain passive ; but most frequently they deter-
mine in the tissue phenomena of reaction that manifest themselves by the
appearance of a cone or white zone, formed by a mass of canalicules obliter-
ated in consequence of a formation of secondary dentine. The tooth attacked
by caries does not remain passive and inert, but may in some measure under-
take to resist its action by the phenomena of condensing dentification of the
ivory. The agent of dental caries is the saliva, become the medium of acid
fermentation or the vehicle of foreign substances susceptible of altering
directly the tissues of the ivory and the enamel. The intimate mechanism of
the production of caries is a simple solution of the mineral and calcareous
salts which enter into the constitution of the enamel and of the ivory, by the
agent of new formation."

Leber and Rottenstein* say : " The action of acids alone does not account
for all the phenomena which appear in caries of the teeth. The acids attack
first the enamel and rapidly change it to a chalky mass ; later on their action
is felt in a marked manner upon the dentine, which becomes more transparent,
and, in fine, as if cartilaginous, by the very slow, but progressive loss of its
calcareous salts. Caries, on the contrary, proceeds slowly in the enamel ; it
is much swifter in the dentine, where it proceeds promptly along the eanali-
culi. This difi'erenee of progi'ess must be attributed to the participation of
the fungi in the work of the caries. The elements of the fungus glide easily
into the interior of the canalieuli, which they (lilak-, and thus favor the passage
of the acids into the deeper parts ; these same elements cannot penetrate a
compact enamel, or at least they enter more slowly, and only when the ele-
ments which form it have been greatly changed by the action of acids. . . .
For them (the leptothrix) to be able to penetrate thus, it is necessary that the
teeth be in a suitable condition ; the enamel and the dentine must have lost
their density by the action of acids."

Carl Wedlt says: " It was quite natural to transfer to the teeth the signi-
fication implied in the expression ' Caries of bone ; ' indeed, the fundamental
phenomena, namely, the destruction of the hard tissues, offered a striking
analogy. In their development, however, the two processes by no means pre-
sent such an identity. Caries of bone, as is well known, is an inflammatory
process (osteitis) which originates in the soft parts of the bone and erodes its
hard tissue. This is not the case with the carious process in the teeth, which
commences in the hard tissues and spreads to the vascularized and nervous den-
tal pulp. In sections made iu a direction transverse to the axis of the radiating
dentinal canals, a gi-eater or less nimiber of canals are met with whose limit-
ing walls (the so-called dentinal sheaths) describe unusually large circles, and
whose cavities are replete with a mass which has in some places a homogeneous,
in others a molecular appearance, and forms convex projections beyond the sur-
face of the section. The transverse diameters of the widened and filled canals
vary, some being at least three times as large as others. The intertiibular
tissue presents a molecular chnuUness, and is beset with grains ha^^ng the
appearance of fat. . . . Since we know that an interchange of material takes
place in the dentine and cement during life, as is jn-oved by the occurrence of
atrophies, hypertrophies, and new formations, and that the dentine possesses
a degree of sensibility, we cannot reject absolutely the idea of a reaction on
the part of both hard tissues against the effects of external agents. Some

* " Dental Caries and its Causes," 1873. t " Pathology of the Teeth," 1872.

TiiK ti:i:tit. 073

authors seem to have had a?i iiitiinutioii of this idea, since they were inclined,
to consider tlie textural clianj^i'S in carions dentine as vital processes. There
can be no doubt that the sensii)ility, soinetinu-s increasinf^ to actual pain, of
the dentine, when deprived of its ])rotectinf? coverinj^, is a vital action, and
that this becomes diminished when the most sensitive, the peripheral portion,
is destroyed l)y an external a^ent. These facts, however, are by no means
sufficient to enable us to draw a conclusion in favor of the reactionary power
of dentine in parts wliich are attacked by caries. In consequence of the
decomposition of the secretions, acids are formed which extract the calcareous
salts from the hard tissue, and give rise to a disintegration of the affected
portions of the latter, in wliich no inflammatory reaction occurs."

Tomes* says: "Although dental caries has been investigated and de-
scribed by all who have written upon the subject of Dental Surgery, from
the earliest period when disorders of the teeth first attracted attention down
to the present time, yet it can scarcely be said that the nature of the disease
is perfectly understood, for even now two hypotheses prevail. In one the
disease is assumed to be no disease whatever, but merely the result of
chemical solution of the dental tissues, and therefore dependent both in its
origin and its progress on the imcontrolled action of physical and chemical
laws. According to the other hypothesis, the fact that teeth are part of a
living organism, if not essential to the origin of the mischief, at all events
profoundly modifies its progress. . . . Caries is an effect of external causes
in which so-called ' vital ' forces play uo part."

The processes concerned in the destruction of the temporary
teeth were studied in my laboratory by Frank Abbott, but the
result is not yet ready for pul)licatiou. The bay-like excavations
observed in the cement and the dentine are due to a dissolution,
first, of the lime-salts, and afterward of the basis-substance, which
causes the reappearance of bioplasson in certain pre-formed ter-
ritories. The new infiltration of these territories with basis-
substance often results, even in the dentine, in a formation of
bone-tissue, and it is probable that the same process takes place
in the enamel also. How much of the erosions, which are visible
in these structures, is due to a growth of granulation tissue into
the dental tissues from mthout, has not yet been positively
determined.

The development of the teeth has for a numl)er of years been
studied in my laboratory by C. F. W. Bodecker, and these
studies are not yet completed. One of the important facts
gained by the researches of Bodecker is, that the views held by
former observers, concerning the development of the enamel,
is erroneous. It is true that the enamel starts as an epithelial
prolongation of the oral cavity, but the epithelia themselves
never participate in the formation of enamel. The epithelia

* "System of Dental Surgeiy," 1873.

43

674 THE TEETH.

break down into medullary corpuscles, from which arises the
well-known graceful myxomatous tissue. This tissue again
returns to the medullary condition before producing enamel,
the process being identical to that by which dentine is produced.
Dentine is formed of medullary corpuscles, which are arranged
in rows at the periphery of the papilla, and which afterward
change into the glue-yielding basis-substance, the seat of infil-
tration, with lime-salts. The canaliculi of the dentine are formed
hetu-ecn the medullary corpuscles, and the dentinal fibers arise
from a coalescence of the living matter which is present between
the medullary corpuscles, termed " odontoblasts."

XVII.

THE LIVER.

ri^HE LIVER, the largest gland of the body, is neither acinous
1 nor tubular, but has a peculiar structure of its own. Its
vascular supply is predominantly venous, and is obtained from
the portal system. From this blood the epithelia elaborate a
secretion, the bile, which does not exist as such in the blood.

Corresponding with the lobate shape of the liver, which, how-
ever, is nowhere very distinctly marked, the intimate structure
of the liver is lobular, though in man and in most mamnuils the
lobules also are not sharply defined, but in many places appear
confluent. In the pig's liver the single lobules are easily dis-
cerned with the naked eye. The lobules are composed of epithelia
and capillary blood-vessels ; they are inclosed in fibrous con-
nective tissue, called the interstitial tissue, which is more abun-
dant in some places than in others, and in many localities is
altogether lacking. Around the lobules, in the interstitial con-
nective tissue, run branches of the portal veins, of the hepatic
artery, the bile-ducts, the lymphatics, and the larger bundles of
nerves. In the lobules, capillaries are found which are derived
from veins, and which carry, therefore, only venous blood ; while
the center of each lobule is occupied by the hepatic vein. The
system of the portal veins is arranged at right angles to the
system of the hepatic veins. Where the portal veins are cut
longitudinally, the hepatic vein appears in transverse section,
and rice versa. (See Fig. 296.)

The portal rein, upon entering the hUus of the liver, divides
into smaller veins, which ramify in all directions, only the

676

THE LIVER.

larger branches being surrounded by connective tissue. Between
the lobules the portal vein ramifies into smaller veins, which sub-
divide into capillaries. The latter arise either from one portal
vein, which supplies the neighboring lobules with capillaries, or
from two i)arallel veins, running in a curved direction corre-
sponding with the peripheries of two neighboring lobules. These
veins, which are connected by transverse ramules, split up into
numerous capillaries for the supply of the lobules. The vessels

Fig. 29G. — Liver of a Cat. Injected.

P, P, branches of tlie iiortal veins, partly siirrounrtetl by interstitial connective tissue;
C, capillaries of the lobules ; H, H, central hepatic vein ; B, bile-duct. Magnified 100
diameters.

bordering the lobule are frequently capillary formations, especially
in those parts where a larger amount of interstitial connective
tissue is present.

The capillaries of the lobule are very wide and slightly sinuous.
We never meet with a uniform distribution of capillaries through-
out the lobule, for between wide capillaries narrow ones are invari-
ably found, frequently separating a group of epithelia by their

77//'; LIVFJi

Qll

oiulothc'lial walls, which arc arranged in close contact, without a
marked caliber. This disposition of vessels is, as a matter of course,
less noticeable in injected specimens than in those taken fi-om
livers Avhich are simply hardened. From this fact we may infer that
the capillary system of the lobule is never completely filled \vith
l)lood ; and if the bl()od-su])ply at one surface of an ei)itheliujii
is abundant, the capillar}
at the opposite surface is
closed. It is also admissi-
ble to suppose that, l)y the
enlarj»'ement of a number of
epithelia, during their secre
tory action, some capillaries
are occluded; or lastly, it
may be that new capillaries
are forming- in the lobules
of the liver during the whole
life of the individual.

The capillary meshes are
extremely narrow, so that
there is never room for more
than two complete epithelia
between two capillaries. We
often find, where the capil
laries exliibit a radiating
arrangement, rows of epi-
thelia lying between them ;
and the appearance of these
epithelial rows is caused by the occlusion of transverse capillaries
which connect the longitudinal vessels. The transverse capillaries
in such cases can be recognized by their endothelia with high
powers of the microscope only. As a rule, therefore, one half of
the epithelial circumference will be supplied with blood, although
a greater portion may be encircled by capillaries. (See Fig. 297.)

The center of a lohnle holds the hepatic vein, which arises as an
abrupt widening from the confluence of the capillaries. It is
surrounded by a very small amount of connective tissue, has no
muscle coat, and is never accompanied by bile-ducts or arteries.
The hepatic veins, which always occupy the centers of the lobules,
unite into somewhat larger branches, which are most marked
on the posterior portion of the liver, and are called suhlohular
veins. By the union of these the hepatic veins proper originate.

Fig. 297. — Liver op a Child.

C, cai>illary blood-vessels, partly saplng, partly
occluded, lioldiiig in their meslies the liver epithe"
11a ; _B, bile-capillary (0, cut transversely. Mag-
nified 500 diameters.

678 THE LIVER

The term " interlobular veins " is used to designate the portal
branches lying between the lol)ules, and the terin " intralobular
veins '' the central hepatic veins. These denominations are, how-
ever, superfluous and easily confounded.

The rows of the liver epithelia, as mentioned before, may be
either single or double — i.e., there may l)e a capillary blood-
vessel on either side of the epithelium, or the epithelia may lie
close together in one capillary mesh. In places where the capillaries
run in a prevailing longitudinal direction, this relation is not well
marked, as the epithelia overlap the capillaries on all sides; while,
in places (see Fig. 299) where the capillaries are cut transversely,
their relation to the epithelia- — these being arranged wreath-like
around the blood-vessel — is plain. (See Fig. 300.) Some authors
claim that there is never more than one epithelium in a capillary
mesh ; if this were true, the small openings at the corners of
neighboring epithelia (marked B in Fig. 297) would have to be
considered transverse sections of very narrow or occluded capil-
laries, and not bile-capillaries. In the human liver it is impos-
sible to decide in every instance whether a minute transverse
section in the middle of an epithelial group is a narrow capillary
blood-vessel or a bile-capillary. Much (confusion has been caused,
especially in the description of morbid processes, by the inability
of positively discriminating between the two above-named forma-
tions. Those who claim that the bile-capillaries have an
endothelial investment certainly must have mistaken capillary
blood-vessels for them.

The liver epithelia form a continuous layer around the capil-
lary blood-vessels, although in thin sections their continuity
appears interrupted by the calibers of the capillaries. In the
himian liver the single epithelia are cuboidal, irregularly polyhe-
dral ; in the rabbit's liver, more or less he;sagonal. They exhibit
one or two nuclei ; the latter condition being rarer in the human
than in the ral)bit-s liver. In the nuclei, as well as in the body of
the epithelia, the reticular bioplasson structure is visible, as seen
in all living elements of the tissues, including the epithelial.
The Hver epithelia are separated from each other by a light, nar-
row rim of cement-substance which is traversed at right angles
by extremely delicate filaments, identical with the so-caUed
" thorns " or '' prickles " met with in other epithelial formations.
These features were discovered in my laboratory by H. Chr. Miil-
ler. The bile-capillaries are simply excavations in the cement-
substance. (See Fig. 298.)

TlIK LI VEIL

679

The moslies of tlic l)i()])liiss()ii rcticuhiui of the liver epitlielia,
sliortly Jifter udmiiiistratioii of fatty food, contain fat-granules
and sometimes brown pigment-granules (of the bile '?), especially
in the vicinity of the Ijile-capillaries ; a diffused brownish pig-
nuMit is invaria])ly present. The cement-substance holds, as will
be shown later, the terminal nerve-fibrillie. At the border next
to the capillary wall a light rim is visible, traversed by delicate
filaments, which directly unite the
bioi)lasson reticulum of the epi- \\

thelium with that of the endo
theUal wall of the capillary. ^JiM^^^^&tifMiM^^^i^ — cn

The hilp-cdpUlat'hH were first
described by J. Cxerlach, and, as
mentioned before, are excava-
tions in the cement-substance be-
tween the epithelia, always at the
surface of the epithelium, oppo-
site to the place which comes in
contact with the capillary — the
point, therefore, of the least
pressiu'e. By some authors they
are termed intra-lobular bile-ves-
sels, while those called the inter-lobular bile-vessels, and running
between the lobules of the liver, correspond to the bile-ducts.
The bile-capillaries are destitute of an epithelial investment, and
are also without a structureless wall of their own. Their loca-
tion being between two neighboring epithelial surfaces (see Fig,
298), a portion of the bile- capillary is surrounded and enclosed
by the cement-substance, while other parts of its circumference
are in direct communication with the interior of the adjacent
epithelia — that is, with the meshes of the bioplasson reticulum.
Thus, it becomes intelligible that, by an active contraction of this
reticulum, the newly formed bile is forced into the place of the
least resistance and pressure — /. e.^ the bile-capillary.

Successful injections of colored gelatine into the bile-capil-
laries, by E. Hering, prove that in the rabbit's liver all these
vessels pursue a course corresponding to the middle of the
epithelial surface, and I can, from my own observations, cor-
roborate the statements of Hering. In the top view, the hexagonal
epithelia appear to be surrounded by a rim of injected colored
material, and it is only the darker dots in the middle of a
colored line, corresponding to the middle of an epithelial sur-

FiG. 29 S. — Liver Epithelia op
THE Rabbit. [Published by H.
Chr. Muller in 187G.]

C.S', cement-substance between tlie e])i-
tlielia ; BC, bile-cai)illary excavated in the
cement-substance. Magnified 1200 diame-
ters.

680

THE LIVER.

face, which indicate the location of the l)ile-capillaries. In places
where the blood-capillaries arc cut transversely, most of the
bile-capillaries will also appear as darker dots between those
surfaces of neighboring epithelia which are most distant from
the parts that are in contact with the capillaries. (See Figs.
299 and 300.)

Fig. 299.— Relation between
THE Capillary Blood-ves-
sels AND THE Epithelia, in
A Longitudinal Direction.
Liver of a Rabbit. Bile-
Capillaries Injected.

E, liver ei)itlielia ; B, Tjile-capillaiies ;
C, capillary Wootl-vessels. Maguitied
1000 diameters.

Fig. 300. — Relation between
the Capillary Blood - ves-
sels AND THE Epithelia, in
A Transverse Direction.
Liver op a Rabbit. Bile-
Capillaries Injected.

E, liver epithelia ; B, bile-capilliuie.s ;
C, capillarj' blood-vessels. Magnified
1000 diameters.

In the liver of the cat the relations of the bile-capillaries to
the epithelia are somewhat different, inasmuch as the capillaries
run both along the surfaces and the edges of the epithelia (see
Fig. 302). In the liver of man most of the bile-capillaries run
along the edges of the epithelia, and to this is due the appear-
ance of the small, light apertures, which are seen at the point
where three or four epithelia meet (see Fig. 297). The difficulties
in discriminating between occluded blood-capillaries and bile-
capiUaries I have before alluded to. Should the conception be
correct, that several liver epithelia lie around a central bile-
capillary, while the opposite broad surfaces of the epithelia are
in contact with the blood-vessels, a tubular arrangement of the
liver epithelia might become admissible. Some authors have

rill-: I.I villi.

r.si

alrciidy claiincd tliat tlic liver of man can Ix' classified aiiionjif
the tubular i,dauds (Hiesiadecki). In linnian enil)ry<)S these rela-
tions are still more mai"ke<l, and for this reason Toldt and
Zuckerkandl have maintained that the sti'ucture of the liver of
liuman i'ml)r\'os is tnhular. each ])ile-eai)illaiT heinji: surrounded
by from three to five liver ei)ithelia ; the transformation into
liver-strneture proper beji^iii^, according to these authors, after
birth. But, in fact, there is no difference between the liver of
an embryo, that of a child six years old (see Fig. 277), and that
of adults, with tlie exeeption that the
indiWdual epithelia appear larger with ^f^^ /' ,
the advancing development of the {^^:|,i|5i ^
Uver. (See Fig. 801.) ^^ "

In places where interstitial eon- ^^^J^^^o^ ^*P'
nective tissue is most abundant, the " - '''^ ' -^^v^';^*''
bile-eapillaries, upon approaching the
periphery of a lobule, produce a sys-
tem of canals l\ang between the outer-
most epithelia and the connective
tissue, and inosculating with the hih-
(lucts. These at first are only slightly
larger than the bile-capillaries, and
by their union at right angles i)roduce
larger tubules, which invariably' run
in the interstitial connective tissiie
only. The epitlielial lining, at first
composed of fiat and small bodies,
gradually becomes more distinct, as-
suming the characters of euboidal
epithelia, while in the largest ducts the

epithelia are distinctly columnar. Toward the central caliber
the cement-substance produces a distinct investing layer, which
in the larger ducts is studded with short rods (Virchow), similar to
those of the columnar epithelia of the intestines. In the smaller
ducts the connective tissue is not differentiated into a separate
investing layer, while the larger ducts have such a layer, pro-
vided with elastic fibrillar and a reticulum of capillary blood-
vessels ; smooth muscle-fibers are also met with in the wall of
the larger bile-ducts. (See Fig. 302.)

E. H. Weber has described as i'a.<ia aherraufia bile-ducts which
occur, sometimes in large numbers, in membranaceous forma-
tions on the outside of the liver-tissue, where, evidently, in the

Fig. 301. — Liver op a
Human Fcetus op Five
Months.

E, epitlielia, arrauged around a
rentral bile-capillary ; C, capillarj'
blood-vessels, containing a lew
blood-corpuscles, tlieir endothelial
wall detached from the surface of
the liver ei)ithelia. Magnified 500
diameters.

682

THE LIVER.

more advanced stages of development of the liver an atrophy of
the tissue had taken place. Such formations arc found at the free
border of the left lobe, in the noighl^orhood of the portal vein,
near its entrance into the porta, and in the connective tissue
surrounding the gall-bladder. These bile-ducts in some parts
show very wide calibers, and in others are in the process of oblit-
eration and transformation into connective tissue.

The interstitial connective tissue is more abundant the nearer
it is situated to the porta of the liver ; it is in direct connection
with the connective-tissue layer of the peritoneum, which, in this

PD

Fig. 302. — Bile-Capillaries, Uniting into Bile-Ducts.
Injected Liver of a Cat.

r;, interstitial connective tissue; P, portal vein, branching' into capillaries, C; J?C, bile-
cai)illaries; ^i>, Tjile-dnct. Magnified 1000 ilianieters.

locality, bears the superfluous name of Glisson's capsule. In it
we meet with large veins, all of which are necessarily portal ;
with arteries, — viz. : the branches of the hepatic artery, — and
with capillaries and lymphatics. We find transverse and longi-
tudinal sections where the union of the smaller with the larger
ducts takes place. The smaller ducts often lack a distinct bore, evi-
dently from being compressed ; while the larger ducts, having a
distinct lining of columnar epithelia, always exhibit a distinct
circular caliber. (See Fig. 303.)

nil': LivKR.

683

At the whole ])ori])lH'i'v of the liver the iiitei-stitial eonneetive
tissue is in eoimeetion with tiie peritoneal ea})sule. Jiesides, there
is also a sli<i:ht aniouDt of connective tissue said to accompany
the eapillarv blood-vessels within the lobule.

The larfjer ])ile-duets are composed of fibrous connective tis-
sue, in which numerous acinous or racemose mucous glands are
imbedded. These glands, especially in the larger vasa aber-
rantia, exhibit the currant-like shape, and are arranged in regu-
lai- double rows along the longitudinal axes of the ducts.

Tlie (/(il/-hli((l(h'r, as well as the three largest l)ile-ducts, are
lined by a connective-tissue layer abundantly supplied with

Fig. 303. — Ixterstiti\l Tissue of the Lher of a
Child, near the Porta.

G, fibrous interstitial connective tissue — so-called Glisson's capsule ; P, portal vein ; C,
capillar}- blooil- vessel ; D, If, bile-dncts cut in longitudinal and transverse directions; A,
artery in transverse section ; L, lymphatic. Magnified 500 diameters.

blood-vessels forming ridges in the bladder. Next to this follows
a layer of smooth muscle-tibers, which freely interlace, and the
outermost layer blends with the structure of the covering perito-
neum. The inner lining consists of columnar epithelia, which,
are prolonged to form mucous glands (Luschka).

The hepatic artery is, in comparison with the size of the organ it
supplies, a small vessel, entering the porta with the portal veins.

684 THE LIVEB.

Its branches are found only in the interstitial connective tissue
(see Fig. 303). It furnishes the capillaries around the larger
portal veins and bile-ducts, and those supplying the outer capsule
of the liver. The capillaries of the interstitial tissue are said,
by some authorities, to inosculate directly with the capillaries of
the lobule ; whUe others maintain that small veins arise from
the interstitial capillaries and unite with the portal veins.

TJie hjniphatics of the liver are found in moderately large
numbers in the interstitial tissue and in the capsule. A portion
of these vessels leave the liver at the porta, where they form a
plexus around the portal veins and the hepatic artery, and
another portion issue from the periphery through aU peritoneal
reduplications, which unite the liver with the adjacent organs.
The lymphatics have everywhere endothelial Wtills of their own.
Von Wittich succeeded in injecting the lymphatics of the liver
by forcing a concentrated solution of indigo-carmine into the
trachea of rabbits recently killed by exsanguination. He saw,
besides the above-mentioned plexuses, other plexuses around the
hepatic veins, and claims that from the interlobular lymphatics
prolongations pass into the loluiles between the capillaries and
the liver epithelia.

The Termination of the Nerves in the Liver.
By M. L. Holbrook, M. D.*

As the best histologists have maintained that our knowledge of the termi-
nation of the nerves of the liver is very slight and imperfect, I have under-
taken, by a careful and extended series of researches, to throw some light
on the subject. I have examined livers from the following- animals : the
dog, cat, woodchuck, owl, crow, hawk, and the ox. I have also examined
the livers of a child and of an adult. The methods which I have employed
have been the simple carmine-staining of specimens preserved in chromic
acid, staining with pici'o-carmine, osmie acid, and chloride of gold. None
of these reagents proved of much value, except the chloride of gold. The
use of osmic acid, so highly praised by some observers, in my hands gave
no satisfactory results, for. though it makes medullated nerves plainly
visible by rendering them black, it has scarcely any effect on nou-medullated
nerves, and it is these which are to be found in the liver in a far greater
number than medullated nerves. Chloride of gold, as usually employed,
also failed to give any good results, but in combination with formic acid
they were very satisfactory. The suggestion of a combination of chloride
of gold and formic acid I learned from Lowitt,t and mj- method of employ-

*■ Printed in abstract from tlie author's manuscript.

t " Die Nerveu der glalteu Musculatur." Sitzuugsber. d. Wiener Akad. d. Wissenscli.,
Ixxi. Bd.

77//'; IJVKIL 685

ing it was as follows: Pieces of the fresh liver — best that of man or the
ox — are frozen in a microtome an<l cut into thin sections. These are next
l)laee(l in a half per cent, solution of chloride of f^old for thirty to forty
minutes. After this it is immediately washed carefully in distilled water,
and at once subjected to formic acid of a specific gravity of 1 1 'J from five to
eight minutes. The thinner the sections the less time is required for the acid
to act upon them. Immediately after their removal from tlie formic acid
they must be again thoroughly washed in distilled water and exposed to the
light, and then mounted in glycerine.

The place most favorable for finding nerves is the porta. In the ox, in the
region where the large vessels enter the liver, there is considerable fibrous
connective tissue, in which numerous bundles of mostly non-medullated nerves
may be seen coursing in the interstices between the bundles. I have
succeeded best by taking sections from a portion of liver immediately border-
ing on the hepatic artery, a few inches from its entrance into the organ, or
some of its branches. I am also of the opinion that the best sections are made
by placing the material in the microtome in such a manner that the sections
are cut vertical to the artery.

The nerves are marked by a large number of nuclei, by the presence of a
delicate sheath of perineurium around each fiber, and by the dark violet color
they had taken on from the treatment before described.

On the border of the lobules the nerves, which were still in bundles of
from three to five, sometimes more, ramified and entered the lobules in dif-
ferent places, mostly branching at acute angles along the capillary blood-
vessels. As I have traced the nerves entering the lobule to theii' connection
with the bundles of nerves between the lobules, no doubt can arise as to the
nature of the fibers which I have seen. Such fibers are to be found in the
interlobular connective tissue distant from the porta, as well as in the con-
nective tissue of the porta itself. Unquestionably, therefore, the nerves pass
into the lobules and ramify along the capillary blood-vessels. This assertion
is based on the fact that the ramifying nerves were always seen running in
the light interstices between the Uver epithelia, which, as we know, are
occupied by capillary blood-vessels only.

The further course taken by the nerves can be understood only by consid-
ering the fact hitherto imknown to all observers — namely, that the liver
epithelia are separated from each other by a delicate layer of cement-sub-
stance, in the same manner as all other epithelia and endothelia. The
significance of the thorns contained therein, according to the views of
C. Heitzmann, is plain. The reticulum in epithelia of all kinds was first
described by this observer in 1S73, and it deserves mentioning that several
years later E. Klein, of London, claimed to be the first to describe the retic-
ular structure of the epithelia of the liver. Liver epithelia are in no way
different from other epithelia, and the reticulum has been proved bj"^ H. Chr.
Miiller to be composed of li^^ng matter, while Klein does not appear to have
any idea of its significance. The reticulum is connected in the center of the
epithelium with the wall of the nucleus, and at the periphery with those
filaments which penetrate the cement-substance, and interconnect all neigh-
boring epithelia. A light rim of this cement-substance is always present
between the endothelial wall of the capillaries and the adjacent wall of the
epithelium, and again this rim is traversed by delicate grayish filaments eon-

€86

THE LIVER.

necting the wall of the capillary with the reticulum of living matter in the
epithelia. This rim of cement-substance proves to be the place where the
finest fibrillse of nerves course. In specimens treated with chloride of gold
and formic acid, all structures, except the nerves, were more or less muti-
lated and rendered indistinct ; but, in specimens previously hardened with
chromic acid, washed with distilled water, and stained with a half per cent,
solution of chloride of gold, the relation between epithelia and capillaries is
very plain. The details can be seen only with high power (1000 to 1200
immersion) and excellent lenses. The beaded nei'%'e-fibrillae are connected
by means of delicate threads with the wall of the capillary blood-vessels, as
well as the threads in the cement-substance between epithelia. Sometimes
the nerve-filament is so closely attached to the wall of the epithelium, or to
the capillary, or to both of them, that the light intervening rim and the

Fjg. 304.— Diagram of the Terminal Nerve-Plexus
OF the Liver.

-P, portal vein; D, bile-rtnct ; L, capillary vessels in a lonfritiuliiial, T, in transverse sec-
tion : E, liver epitlielia ; Ji, bundle of non-meilullated nerve-tlbers ; A, axis-fibrilht, penetrating
tlielobale; N, axis-tibrilhe in the ceuient-substauce between epitlielia.

interconnecting filaments cannot be seen. In other cases, the relations are
plainly marked. (See Fig. 304.)

In the cement -substance between the epithelia I have seen delicate fila-
ments around the capillary blood-vessels, which from analogy I think I am
justified in taking for nerves. These were visible with high powers in speci-
mens stained with carmine, but more plainly in specimens stained with

THE LIVER. 687

ohloride of gold. In none of my laiKc nuinbt-r of specimonH have I ever been
able to trace a nerve-filament jx-iu'tratint^ into an epithelinm, as is claimed to
occur bvE. PHiiger. Once or twice I observed a peculiar, ])eur-Hhapcd enlarge-
ment of the nerve which seemed to be attached to an epithelium, but it waH
evidently only a swelled nucleus of a non-medullated nerve, without a real
attachment. It often happens that a large non-medullated nerve-fiber ex-
hibits an oblong, pear-sluiped, nucleus-like formation in the axis of the fiber,
whose continuity beyond the nucleus is represented by extremely delicate,
beaded axis-fibrilhe.

My rcseardivs are in accordance nitli M. Nesterou-.'ikifn asscrtionN that tlic
blood-ressel.'i of the liver, both the larf/er vessels of the porta and the capillaries
within the lobule of the liver, are accompanied by filaments of nerves. These course
in the cement-substance between the walls of the capillaries and the epithelia, and
also in the cement-substance between neiyhboring epithelia, tvithout ever entering
the bodies of the latter. As the filaments traversing the cement-substance are
formations of living matter the same as the nerve-filaments, and are in connection
with tlie reticulum of living matter in the epithelia, ice can, I think, understand
how nervous impulses may be transmitted from the serves by these bridges, the
formerly so-called thorns, directly to the epithelia.

E. Pfliiger* first asserted ha\'ing seen meduUated nerve-fibers reaching the
surface of the glandular epithelia in salivary glands and in the liver. Accord-
ing to him, the nerves close to the epithelia lose their myeline investment,
and are continued as non-medullated nerves penetrating the epithelia and
terminating in the nucleus. His assertions have not been corroborated by any
observer. I must deny the coiTectness of all his assertions concerning the
termination of the nerves in the liver.

Kupfert claims to have seen a few nerves enter the epithelia of the aci-
nous glands along the oesophagus of the blatta (cockroach). As a re-agent he
used only the vapor of ammonia.

M. Nesterowsky,t in his very accurate researches, has found the truth,
and I concur with him in his statements, to which I have added a few more
facts. This author used the fresh livers of the cat and dog, the blood-vessels
of which he injected with colored glue. He used as a re-agent the chloride of
gold in different degrees of dilution, and afterward placed the specimens in
acetic acid for a few days, adding a di-op of ammonia saturated with sulphur-
etted hydi'ogen.

Pailiology. The pathology of the liver offers a wide field for
research. This organ is often subject to injiammation, which is
either plastic and terminates in a new formation of connective
tissue, — the so-called cirrhosis, — or the inflammation is suppu-
rative, resulting in the formation of abscess. Both forms have
been studied in my laboratory, as shown by the following articles.

* "Xacliweisder Xervenendiguugen in den acinosen Driisen unrt in der Leber." Ar-
chiv fiir Pliysiologie, 1871.

t " Das Verhiiitniss von Driisenuerven za Driisenzellen." Archiv fiir Microscop. Anato-
mie, B«I. ix., 1873.

t Ueber die Nerven der Leber. Vircliow's Archiv, Bd. Ixiii., 1875.

688

THE LIVER.

Catarrhal or Interstitial Hepatitis.
By Dr. H. Chr. Muller, New-York."

The epithelia of the liver have a reticular structure common to all "proto-
plasmic " bodies ; the granules, which are points of intersection of the reticu-
lum, are rather coarse in the liver epithelia of man, and in that of the cat,
but very fine in that of the rabbit. All epithelia are separated from each
other by light rims of cement-substance, traversed by delicate, conical fila-
ments, identical to those which connect the granules within the epithelia.
The presence of these formations readily explains a number of morbid proc-
esses, for it is only the living matter forming the reticulum and the connecting
threads in the cement-substance which is capable of growing, proliferating,
and of producing new elements and new tissues. These new formations may,
however, deviate considerably from the type of the original epithelia. The

Fi<i. J05 —Cirrhosis op the Li\er.

i>, L'i, loljules of tlie liver, consiilfral)ly decroased in size, partly l>leii<ling with the inter-
stitial connective tissue, without a marked liouudary; T^i, 7^^, interstitial tissue greatly aug-
mented, lioldinjr a moderate amount of blood-vessels. Magnitied '2()() diameters.

bile-capillaries are excavations in the cement-substance, and are without
walls of their own. In transverse section the injected bile-capillaries appear
circidar in the liver of the cat and oval in that of the rabbit.

In interstitial hepatitis low powers of the microscope show a considerable
increase of the interlobular connective tissue at the expense of the lobules.
The vascular supply of this tissue varies greatly in different parts ; in some
places blood-vessels are numerous, while in others so scanty that even in
injected specimens large districts are almost without them. In localities

* Extracted from the author's paper, " Beitrage zur Keuntniss der interstitielleu Leber-
entziinduug." Sitzungsber. d. Ak.adeniie d. Wisseuscli. in Wieu, Bd. Ixxiii., 1876.

TllK LIVKU.

0H9

where the iiiflammution has reacliecl a hij^li drj^nM^ tin- h>biiles are reduced to
less tliaii a tliird of tlieir normal diameter, and, inuiuestionably, many of
them perisii altoj^etlier. Tlie boundary between the ilecreased lobules and the
surrounding tissue is not everywliere sharjdy marked, inasmuch as formations
characterized by a brownish color penetrate the interstitial tissue to varying;
depths, iiulicating that a transition of one kind of tissue into the other is tak-
ing place. We also notice that the liver epithelia are no longer arranged in
regular rows and tracts (this fact was known to former observers), but are
now clustered in groups or separated from each other by broad interstices.
(See Fig. ;{().■>.)

In order to answer the query what are the changes that have led to such
a considerable wasting of the epithelia, we must examine places where there

-^^

—u

Fig. 30G. — Boundary of a Lobule of a Cirrhotic Liver,

TOWARD THE INTERSTITIAL TiSSUE.

E, coalesced groups of liver ei>itlielia, in part coutainiug fat-globules; J/, medullary cor-
puscles sprung from liver epithelia ; C, interstitial connective tissue, with blood-vessels ; B,
cross-section of a bile-duct. Maguitied 500 diameters.

is no marked boundary between the epithelia and the interstitial tissue.
Here we see that in many places the cement-substance between the epithe-
lia is missing. A number of epithelia have coalesced into groups destitute
of cement-substance, or exhibiting only traces of it. Most of the gran-
ules of the epithelia are enlarged, manv of them reaching the size of

44

090

TIIK LIVEli.

micleoli ; others appear as nearly liomof^eneous, shiiiiiif^ luiiiiis of a brownish
tint. In this process of growth tlie granuk^s of tlie nuclei also participate,
and, where l)efore a nucleus was present, we often tind coarse granules inter-
connected by filaments. Through the increased size of the granules and the
coalescence of neighboring ejjithelia, large, coarsely graindar liodies arise, in
which, evidently by an outgi'owth of some of the granules, new niiclei appear,
never attaining, however, the size of the original nuclei. (8ee Fig. 'AOi).)

In the next stage we observe marks of division appearing in the multi-
nuclear bodies, and thus various-shajjed elements arise, which remain inter-
connected by delicate filaments traversing the light rims. They form the

Fig. 307. — Boundary of Two Lobules of a Cirrhotic Liver
Toward the Interstitial Tissue.

i'', coalesced liver epitlielia; E^, multiuncleav bodies, sprun.c: from ei>itlielia ; M, niertul-
laiy corpuscles, the offsiirins of the epithelia ; J, interstitial connective tissue, holding hlood-
vessels; d, irregularly sinuous capillaries. Magnified 600 diameters.

indifferent, medullary, embryonal, or granulation tissue, which still retains
the original brownish-yellow color of liver epithelia. As some of the cor-
puscles are infiltrated with basis-substance and others elongated into spindles,
they produce the so-called "young or tinripe" connective tissue. The inter-
stitial tissue is, to a great extent, composed of these spindles. These forma-
tions, which with low powei's of the microscope strongly resemble fibrillae

rill': i.iVF.K. (i<)l

with liifjlior ])o\V(>rs, arc shown to }»e iiari'ow, spiiidlc-shiiiied elomoiits, the
niTHiif^onuMit of whifli in rows produces the filirous appearance. At first this
tissue lias but little basis-substance, and th«' spindles exhiVjit a delicate
granulation, owing to the presence of the reticulum of living matter. The
greater the amount of firm ])asis-substance present, and the more nearly
the connective tissue resembles cicatricial tissue, the moi-e its striatal or
fibrous character becomes apparent, although in these places tlie primary
spindle shape of the elements may still l)e recognized.

I have demonstrated that the transition of epithelium into connective
tissue takes place, and I further maintain that the living material of the epi-
thelia, under anonuxlous conditions, is capable of proliferation, and the result
of this proliferation is connective tissue. (See Fig. 307.)

The relation between the liver epithelia and connective tissue in the pro-
cess of cirrhosis has repeatedly l)een the subject of study.

C. Rokitausky * says that the reticula of the liver-cells l>ecome pale, and
finally disappear in a reddish-gi-ay or grayish mass of connective tissue. In his
view the liver-cells first l>econie cloudy, afterward shrivel and disintegrate into
a detritus mixed with granules of l)ile-piginent, which at last disappears also.

Holm t and HiUtenlu-enner t nuiiutained that in traumatic inflammation
the liver may l>e directly converted into connective-tissue cells.

Kiudfleisch v^ likemse assumed that, in the formation of the frame of
cancer, a transformation of liver-cells into connective tissue takes place.

A. Winiwarter, II on the contrary, is convinced that, at least in the human
liver, the epithelia are never changed into connective-tissue cells, but that
the epithelia simply perish, and all the newly appearing connective tissue
originates from the interlobular connective tissue of the liver.

Hiitteubrenuer, by inserting a needle into the liver-tissue, has caiised,
around the circumference of the needle, transformation of the liver epithelia
into spindle-shaped bodies. Very likely it is merely the mechanical pressure,
which, in the \'i»inity of sarcoma or carcinoma nodules, leads to the spindle
shape of epithelia. In cirrhotic livers such spindles are of not infrequent
occuiTence, and it is possible that tjiey may be compressed liver epithelia ;
but they are never the elements of connective tissue directlj- arisen from the
epithelia. Where such a transformation occurs, it invariably is brought
about through the intermediate stage of endogenous new formation of living
matter in the epithelia, and by the subsequent di^'ision of the latter. In the
vicinity of sln-iveled lobules, in the midst of the connective tissue, we occa-
sionally see spindle-shaped clusters of epithelia. It is quite possible that
these comparatively little changed groups have escaped the process of trans-
formation, as is indicated by their browTiish-yellow color. On the other
hand, the assumption is admissible that they are the remains of the endo-
thelia of larger blood-vessels, or of the epithelia of bile-ducts. (See Fig.
308).

Fatty degeneration is of common occurrence in cirrhotic livers. We often
see in an epithelial body, globules which, after being treated with strong
alcohol, leave empty spaces ; or sometimes, within the epithelium, small fat-

" LehrbucliiU-r Piithol. An.itonue," 1861.
t " Sitzunj;sber. d. Wiener Akad. d. Wisseuscli.," 18G7.
t " Archiv f. Mikro.skoi). Anatoniie," Bd. v.
>< " Lelirbuch der Pathol. Gewcbelehre," 1873.

II " Wiener Mertiz. Jalirbiicher," \ST1.

G92

THE LI V Eli.

granules are seen connected by delicate filaments witli neighboring granules.
In some places the fatty metamorphosis readies liiu:h degrees, invading sin-
gle epithelia, the remnants of wliich are found around the fat-globule. This
process, however, is apparently not very common ; more frequently, by coa-
lescence of several epithelia, midtinuclear bodies arise, which are in part or
wholly transformed into fat, or the division of the body into irregular medul-
lary elements has already been accomplished before the fatty metamorphosis
had started. The manner in which the fatty change proceeds is as follows :
Some of the coarse granules in the epithelia assume a peculiar, dull luster,
and their contours become indistinct ; then a number of fat-gi-anules appear
in an epithelium, but what their further changes are I am unable to tell.
(See Fig. 309.)

AVhere several epithelia coalesce by a liquefaction of the cement-sub-
stance, it is certain also that a number of bile-capillaries perish. In other
places, on the contrary, the ledges of the cement-substance are considerably
widened, and we may safely conclude that a secretory activity of the epi-

Fig. 308. — Boundary of a Lobule uf a Cirrhotic Liver
toward the interstitial tissl'e.

i, liver epithelia; i?', JB', spiiidle-sliapetl reniiiants of liver epithelia: C, row of luetlullary
corpuscles, probably arisen from a former blood-vessel; B^. B^, bile-ducts iu cross-sectioii.
Magnified 500 diameters.

thelia is possible up to the time when they are transformed into medullary
corpuscles. Thus we can understand why the secretion of bile is interfered
with in the highest degi'ees of cirrhosis only.

Larger bile-ducts are sometimes found in abundance in the interstitial
connective tissue, and they may be recognized as such so long as their
epithelium remains unchanged. Should this epithelium proliferate, in eon-
sequence of the endogenous outgrowth of living matter, it becomes impos-
sible to distinguish between bile-ducts and similarly changed blood-vessels.
I could never discover any new formation of bile-duets, although it has been
maintained by some authors that such a formation does occur.

THE LI V 1:11.

r,!):j

A largo number of the capillaries of tlie lobules are destroyeil in the
process of cirrhosis ; for injected specimens i)lainly demonstrate that the
calibers of most capillaries are considerably narrowed, and not permeable tf)
the injected gelatine. Other capillaries, on the contrary, are irregularly
widened (see Fig. liOft). Thus we meet, besides capillary blood-vessels
engorged with blood, solid cords, which from their course must be consid-
ered as obliterati'd blood-vessels.

Fig. 309. — Cirrhotic Liver. Blood-vessels Injected.

31, iiuiltiiiuclcar bodies, sprung from liver cpitlielia ; F'', partial traiisfoiination of an
fpitlieliuin into fat ; f , F^, complete transformation of eijitlielia into fat ; C, C'*, irregular
capillaries — injected. Magnitied 500 diameters.

First, the vascular walls appear thickened and transformed into nearly
homogeneous, yellowish, shining tracts, in which the boundary lines of former
endothelia are no longer recognizable. This change causes a noticeable
narrowing of the caliber, while later the walls fuse together into a solid cord.
In such a pord a differentiation takes place into small medullary corpuscles,
analogous to those arising from the liver epithelia, and xn-oducing an increase
of connective tissue. In this manner numerotis blood-vessels are obliterated
and perish. The interstitial connective tissue in cirrhosis of the liver is
known to be scantily supplied with blood-vessels.

The results of my researches are the following :

In the normal liver of man, cat, and rabbit, the glandular epithelia are

(Jij4r THE LI VEIL

scpanifefl from cacli otlif-r hij ccmoit-siibstance, which is traiersifl hij the spokts
connectituj the epithilia. The hUt-CdjiiUariea are excarations in the cement-stih-
.fta>ic€.

In interstitial hepatitis the lirintj matter of the liver epiihelia is augmented
and the cenient-snbstance is in part liquefied. From coalesced (/roups of liver
epithelia multinuclear bodies arise, which, through the formation of new cement-
substance, break up into a number of indifferent elements. These f/ire rise to an
abundant new formation of connective tissue.

Ill the process of liquefaction of the original cement-substance numbers of bile-
capillaries are destroyed. The blood-vessels, through an increase of the living
matter in their walls, are transformed into solid cords, which afterward divide
into indifferent corpuscles, and at length give rise to fibrous connective tissue.

In miliary tuhercidosis of the live)' the iuiiammatorv uew for-
mation invariably stari:s in tlie interstitial eonueotive tissue. The
smallest nodules discernible In* the aid of the microscope are
found to consist only of globular clusters of inflammatory cor-
puscles, in which noformei* constituent structures (veins, arteries,
and ducts), are recognizable, and for this reason it is impossible
to determine from which structure the tuberculous formation
originated. Large tubercles are formed at the expense of the
epithelia of the lobules. Avhich are in this case broken down into
inflammatory corpuscles in exactly the same manner as in inter-
stitial hepatitis. The most characteristic feature of this condition
*is the complete destruction of the original blood-vessels and the
absence of a vascular new formation. The inflammatory cor-
puscles are distinguished by theii" small size and the presence of
an indistinct myxomatous reticidum similar to that found in
hnnph-tissue.

Sijphilitir (jumiua originates as an inflammatory process in the
interstitial connective tissue, with subsequent destruction of the
liver epithelia, through their transformation into medullary
corpuscles. All these corpuscles remain interconnected, repre-
senting a tissue ; they give rise to a new formation of basis-
substance, which is only exceptionally advanced to the stage of
fibrous connective tissue, but usually remains homogeneous, and,
as a rule, exhibits waxy metamorphosis. The basis-substance con-
tains a few small plastids, generally without nuclei ; and larger
irregidar plastids singly or in clusters, which, from their brown
color, may be regarded as being liver epithelia, but slightly
changed. In some places these plastids are abundantly supplied
with dark bro^m pigment-gi'anules, and clusters of such granides
may be found scattered throughout the basis-substance. The
central portions of the gumma are often disintegrated and trans-

'/•///•; LIVE II. 695

fornu'd into a <'rn7nl)ly. cliccsy mass, ouiiiu' to tlic ('(»iii))lt'tt'
abst'iu't' of lU'wlv foi'iiu'd l)lood- vessels.

^^ICKos('()PICAL Studies on Abscess or the Livek.
By J. C. Davis, M, I).'

Abscess of tlio liver is due in most, if not in all eases, to an inflammatory
process in some of the orj^ans of the alxlorainal cavity, from wliich the radi-
cles of the jiortal system take their rise, excepting, of course, those cases
which are due to a parasitic origin (Echinococcus). Abscess of the liver
seems to follow only embolism in the portal vein. These embolisms are due
to transported i)articles of pus or shreds from the wall of some pus-cavity,
whieh, being carried into the portal system, jjroduce either suppurative phle-
bitis in the iiorld Ju/xitis — the so-called 7>///('-/y///e?>/i'/.y — or suppurative process
in any part of the liver in which an embolus may have lodged. The question
why pus or tissue in suppuration, if transmitted into a healthy tissue, should
again produce suppuration, cannot be satisfactorily answered. We know that
pya?mia, which is invariably due to a primary suppurative process on the outer
surface of the body, or in an internal organ, is very commonly accompanied
by multiple abscess in the liver. The conclusion that such abscesses are
mainly produced by embolism of pus gains gi'ound, if we consider the fact
that pyaemia ^\^ll never ensue unless suppurative phlebitis be present in the
neighliorhood of the primary suppuration.

My microscopical studies are made on sections from a case of pyasmia.
Sections from this liver, if viewed with a power of one to two hundred diame-
ters, exhibit innumerable foci of inflammation. Some are yet in the earliest
stage, and others in full suppuration. All inflammatory foci have their seat in
the interstitial tissue, built up by the relatively small amount of connective
tissue, which heretofore has been called " Glisson's capsule." Some consist
merely in a slight infiltration of this tissue, others occupy its whole amount
between several lobules, while others are produced by both involution of the
interstitial tissue and the lobules themselves. Lastly, there are inflammatory
foci in which no distinction between interstitial connective and epithelial tis-
sue of the lobule is possible, but all look granular with a low power, which
means that there have already formed, or are forming, small abscesses.

The origin of abscess of the liver is evidently the sime as that of plastic
interstitial hepatitis and miliary tuberculosis of the liver, although the termi-
nation is entirely tlilferent in the three kinds of inflammatory process. In the
process termed plastic interstitial hepatitis, the termination consists in a new
production of dense, fibrous connective tissue, the result being that which we
call ciii-hosis of the liver. In tuberculosis the inflammation leads to a com-
plete loss of blooil-vessels in certain territories, with the result of shrinkage
of the inflammatory elements originating from all the tissues in a cii-cum-
scribed ten-itory. They become separated and isolated, thus producing that
•which we call a tubercle or a dry abscess.

H. Clir. Midler has demonstrated that, in ciiThosis, not only the interstitial
connective tissue and the capillary blood-vessels are transformed into inflam-

*•• Abstract of the author's paper. Archives of Medicine, Augu.st, 1879. In accordance
witli the uonieudature adopted iu this book, the term "protoplasm" Is changed into "bio-
l>1nssou."

696 THE LIVEB.

matory elements, but that the liver epithelia also share in the formation of
such elements, through the increase of the living matter in their bodies. The
result of this is a recurrence of the formation of indifferent or medullary
corpuscles. All these corpuscles remain uninterruptedly connected with each
other, become spindle-shaped, and are partly transformed into basis-sub-
stance, so as to produce a considerable amount of fibrous or homogeneous,
dense connective tissue. Thus, the participation of the liver epithelia in the
inflammatory process fully explains why, in cirrhosis, many of the lobules are
so considerably reduced in size, while the newly formed connective tissue,
which very soon retracts, is so notably and gi-eatly augmented. The objec-
tions which might be raised against Miiller's conclusions are based merely
upon hj-pothetical gi-ounds — viz. : that epithelia would never produce con-
nective tissue, and that, on the contrary, connective tissue never would pro-
duce epithelia. This objection falls to the ground in consideration of the fact
that, in the earliest stages of embryonal development, there are present indif-
ferent or medullary elements only, from which all future tissues must neces-
sarily arise.

As to the origin of the inflammatory elements in tuberculosis of the liver,
direct observations are lacking. It is reasonable to conclude, however, that
in tuberculosis, just as well as in cirrhosis, the liver epithelia themselves
fui-nish a large amount of medullary tissue. I have met with a case of tuber-
culosis in the liver of a duck, in which some of the lobules were partly,
others entirely, transformed into yellow tubercles, e\'idently through the par-
ticipation of the epithelia in the production of indifferent elements.

As to suppuration of the liver, my studies have led me to the convic-
tion that, although the inflammatory process commences in the interstitial
or connective tissue, soon thereafter the epithelia also become involved,
taking their part in the formation of indifferent or medullary elements.

In the earliest stages of interstitial hepatitis, marked only by slight
changes of the connective tissue, we see with higher powers of the micro-
scope (1000-1200 diameters) that the bioplassou bodies — the connective-
tissue cells — are coarsely gi-anular; the nucleus is hidden by the coarse
granules, or it is Aasible in the shape of a shining, homogeneous globule of
living matter. Globules of varjing size are also scattered thi-oughout the
fibrous basis-substance, and have e^adently originated from particles of
living matter, which in the normal condition produce the living reticulum in
the basis-substance. Such formations appear in the largest number around
the blood-vessels, both arteries and branches of the vena porta. Next we
see that the fibrous basis-substance has completely disappeared, and is
replaced by a large number of partly shining homogeneous, partly nucleated
lumps, which are connected with each other by means of delicate threads,
(See Fig. 310.)

In this stage the blood-vessels in the inflamed tissue are as yet recog-
nizable, although their endothelial walls are considerably thickened, the
endothelia themselves being engaged in an active new production of li\ing
matter ; while the central lumen is first narrowed, afterward completely lost
and filled up with inflammatory elements. It is the same process of pro-
liferation which breaks down the portal veins, the hepatic arteries, and the
bile-ducts ; the same process which leads to the consolidation of the capil-
laries within the lobules and their transformation into inflammatory cor-
puscles. In foci of inflammation, where the process has advanced up to the

TKI-: I.IVFJi.

697

fomiation of pns, the eoniuH'tiou of tlio siiif^lc biopluKsoii bodios is lost. Here
isolati'd i>us-cori)usrk's aro susik-ikUmI in the aibuiiiiiious scrum, wliich latter,
in chromic acid specimens such as I have exclusively used for examination,
looks finely ffranular. The epithelia within tlie loltulfs of the liver at the
same time share in the intlanimatory process in a very marked way. Firstly,
they swell uj) ; the cement-substance becomes invisible between a number
of epithelia, which now look like
large, irregular clusters. The
epithelia and the bioplasson
bodies arising therefrom be-
come coarsely granular, with
their living matter augmented
to such an extent that the nu-
clei are mostly concealed ; they
have in part also become in-
creased in size, shining, and
homogeneous. Many of the
granules assume the shape of
nuclei, and throughout the
whole cluster new lines of de-
markation appear, which lead
to the formation of compara-
tively small bioplasson Ijodies,
viz., inflammatory elements.
All these elements are first di-
rectly connected with each
other by delicate threads, and
in this condition represent an
indifferent tissue, closely re-
sembling that formed from the
connective tissue. Lastly, how-
ever, they are completely sep-
arated from each other and
represent pus-corpuscles. (See
Fig. 311.)

The transformation into pus
may be localized in the inter-
stitial connective tissue alone ;
or it may involve the interstitial
connective tissue and a portion
of the neighboring lobules ; or
lastly, a large territory of the
liver-tissue, being engaged in
the inflammatory process,
breaks down into pus. The re-
sult under all circumstances
will be an abscess, varjing only in size. As to the emigi-ation of colorless
blood-corpuscles, which was thought to be the only source of pus (J. Cohn-
heim), I have nothing to say. The origin of pus, in my specimens at least,
could be satisfactorily traced from the breaking down of the tissue itself, so
much so, that in ray opinion the emigi-ated colorless blood-corpuscles, if

<*i — PC

Fig. 310. — Diagram of the Formatiox
OF Pus IN THE Interstitial Connect-
ive Tissue of the Liver.

PV, portal vein ; B, bile-iliict; C, fibrous connect-
ive tissue; if, cluster of inflaniiiiatory corpuscles,
sprunfj; from epitlielia of a liile-dnct : /, liomo^eueous
lumps, first apjiearinj? in the connective tissue; MC,
medullary corpuscles, interconnected ; B'J, i)us-
corpuscles.

698

THE LIVEli.

SFJ

they were present at all, could liave been by no means the main source of
the pus-corpuscles.

Abscess sometimes forms in tlie livei', whicli is never made manifest by
noticeable symptoms — the patient going on perhaps for years, and finally
djing from some other disease, or from some traumatic cause. This never
happens in multiple abscess of the liver in pyemia, as the disease is generally

rapid in its c(jjirse, and death
its result. In a case of forma-
tion of abscess of the liver of
£jp long standing, the abscess be-
comes encysted. The changes
leading to the formation of a sac
around the abscess have been
studied by myself, in a speci-
men in which a liver-abscess of
the size of a man's fist was
formed on the convex surface,
close to the peritoneum, which
was found transforined into a
tough pseudo-membrane of at
least 4 mm. in thickness, and
E G closely adherent to the dia-
phragm.

Microscopic sections, made
through the pseudo-membrane
and the adjacent portions of the
liver, again illustrate the way in
which the pseudo -membrane,
mem\)runa pyogena, had been
formed. It was very plain to be
seen that the interstitial con-
nective tissue of the liver and
the connective tissue of the
PC peritoneiim were broken down
into indifferent elements. The
epithelia of the liver were trans-
formed into medullary tissue in
exactly the same way which I
have described above, when
speaking of the formation of an
abscess. The difference was,
that in the latter instance the
medullary elements were left in
uninterrupted continuity. In
some places the medullary cor-
puscles became spindle-shaped,
and were partly transformed
into a basis-substance, that led to the formation of a delicately striated cica-
tricial connective tissue. The main mass of the medullary elements, how-
ever, had been simply transfonned into a homogeneous or slightly granular
basis-substance, vrith rather scanty bioplasson bodies. Inclosed in this

MC

Fig. 311. — Diagram of the Formation

OP Pus FROM THE EPITHELIA OF A

Lobule of the Liver.

LE, liver epithelia ; C, capillary blood-vessel ;
SE, narrowed capillary, with swelled eiidotlielia ;
EG, coarsely granular epithelia, partly traii8forme<l
into mnltinuclear lumps ; J/C. medullary corpus-
cles, sprung from both the epithelia of the liver
andendothelia of the capillaries, all interconnected;
I'C, pus-coipuscles.

THE r. I VEIL

(')%)

mass I met with scanty cainllary lilood-vcssi'ls, and a larfjo number of islands
of uiiciianfjed liver ei)ithelia, which latter liad escaped tlie truiisforiiiation
into medullary corpuscles and l>«'canit' involved in the newly formed connect-
ive tissue. (See F\\i. HI 2.)

The conclusions I have arrived at are as follows :

1. The ill fid III Illation iiintrinhhj .slart-s in the interstitial eainiectire tissue nf the
lirei; anil seenndarilij innilres a

m

rari/iia/ ainaiint and numljer of
the lolinles of the licei:

2. Both the e.onneetirv tissue
with its blood-ressels and the epi-
thet ia of the lobules, throiie/h an
increase of the livimj matter, be-
eonie transformed into emhryonal
or medullary elements, thus eoii-
stitutini/ what is termed the in-
flammatory infiltration.

H. The medullary eleiuen ts orig-
inally connected irith each other
by means of delicate thorns in
turn become isolated by rujiturc
of these thorns, and now, beiny
suspended in a serous fluid, rep-
resent i>us-corpuscles, the sum
totxd of which is called an abscess.

4. The pus-corpuscles, there-
fore, are a direct offsprinrj of the
liver-tissue, both connective and •
epithelied, and no indication could ^
be seen of an emigration of color-
less blood-corpuscles.

5. On the boundary of the ab-
scess the inflammatory tissue is
transformed into a homocjeneoiis
or striated connective tissue,
buildiny a wall around the abscess.
In the formation of this also the
peritoneum shares, if the abscess
has formed near it.

Fig. 312. — Diagram of the Forma-
tion OF A COXXECTIVE-TISSUE CaPSULE

around an Abscess of the Liver.

MC, medullary corpuscles, arisen from both the
epithelia of the lobule ami the interstitial connect-
ive tissue ; -S', meiluUary corpuscles, spimUe-sliaped,

111 the foregoing article
reference is made to the
probability of embolism of

pUS-COrpilSCleS in the portal i***'^^^' transformed into basis-substance, Ji ; LE,
. . ' islanil of unchanged liver epithelia.

veins, causing pya?mic ab-
scess of the liver. This is in accordance with the older views held
by Cruveilhier, Piorry, Schiih, and others, while Virehow denied
the possibility of such an occurrence.

In microscopic examination of the liver of a man who, after

700

THE LIVER.

extirpation of cancer of the throat, died of pygemia, the first rigor
having; set in fonr days before death, infarctions and abscesses
were found in the Inngs, the liver, and the kidneys, nowhere
large or numerous. (This is the same case to which Dr. A. W.
Johnstone refers in his article, see page 546.) Sections through
the tissue of this liver, at a point where an infarctlT)n the size of

DD

Fig. 31.3. — Suppurative Hepatitis in Pyemia.

PV, poitiil vf iu filled with blood- aud ims-corpuscles ; A, hepatic artery, coiituiuiiis ''l<>"d-
aud pus-corimscles ; LV, lymph-vessel; BU, bile-duct; LE, epithelia of a lobule of the liver.
Magnified 600 diameters.

a hazel-nut had occurred, which, to the naked eye, looked dark
purple-red at its periphery and yellowish in its center, exhibited
the following peculiar features. (See Fig. 313.)

The portal veins were engorged with coarsely granular, irreg-

TIIK LTVFJL 701

iilarly u:l(»l)ular corpiist'h's, red ])l<)()(l-('()i*piis('l<'S, and a finely
jiTaiudar detritus. The coarsely granular Ixxlies were very
numerous, and showed the characteristies of pus-eorpuseles —
viz. : the y-raiiules of livinj;- matter which they contained were of
g'reatly varying sizes. In colorless ])lood-corpuscles, even of per-
sons of a good constitution (see page 62, Fig. 20), the granules
arc more or less uniform in size, and their increase in such an
irregular manner could l)e due only to inliammation. Hence, the
diagnosis of pus-corpuscles in the portal veins was made. These
corpuscles conld not have originated In loco, for the surrounding
connective tissue displayed very slight, if any, inflammatory
changes. A branch of the hepatic artery also contained a lim-
ited number of corpiiscles of this kind — on an average, smaller in
size than those found in the portal veins, and pale, granular
l)lates were also seen in the caliber of the artery, which were
probably detached endothelia of the vessel itself. This specimen
seems to prove that pyaemia is really caused by the embolic
accumulation of pus-corpuscles, which circulate in large numbers
in the whole vascular system. The older views concerning the
cause of pyaemia unquestionably deserve attention, although it is
difficult to explain why pus-corpuscles, collected in a certain nar-
row, vascular district, should excite purulent inflammation in the
neighboring tissues.

At the periphery of the infarction the liver epithelia appeared
unchanged, and the capillaries contained a large number of irreg-
ulai', coarsely granular bodies, in some places completely chok-
ing the caliber, though without producing dilatation. All these
bodies were markedly smaller than those found in the portal
veins, and yet in part slightly exceeding the size of colorless
blood-cor2)uscles. ^ From what I have stated before, a diagno-
sis of pus-corpuscles in the capillaries might be admitted. Still
more striking features were certain elongated bodies noticed in
the calibers of the capillaries, of the size and aspect of epithelia.
The possibility of their being detached vascular endothelia cannot
be denied. If there were a positive proof that cancer epithelia
could be carried into the circulation and produce embolisms in
certain narrow, vascular districts, w^e would certainly be brought
one step nearer to the understanding of how secondary carci-
noma forms by embolism. Such a proof, however, has not yet
been obtained. (See Fig. 314.).

Futtfi deijoteratioH is of rather common occurrence in the
liver. We can trace the transformation of the bioplasson-granules

702 THE LJVEli.

of the epithelia into fat-granules step "by step. By their coales-
cence fat-gloljnles originate, whicli replace the central portions
of the liver epithelia, including the nucleus, wiiile, even in high
degrees of fatty degeneration, every epithelium still shows a
peripheral (sometimes very narrow) zone of unchanged reticular
bioplasson around the central fat-globule. Further studies are
required before positive statements can be made concerning the
nature and cause of fatty degeneration of the liver.

Pifjmeutar}/ degeneration is observed chiefly in livers of persons

■ LE

/'

jii

CE

r

iur-^'r

Fig. 814. — Suppurative Hepatitis in Pyemia.

LJC, uiicliangca livt-r epitlielia ; PC, capillaiy blood-vessels, coutainiug blood- ami pus-
coii)uscles; CE, eiiitlielia (caucer-elements?) in a capillary blood-vessel. Maguified 800
diameters.

who had been for years affected with severe forms of so-called
malarial poisoning. In such livers I have found granules of a
dark brownish or black pigment, accumulated mostly in the epi-
thelia bordering the central hepatic vein, and some coloring
matter was also found, as a rule, in the neighljorhood of the
portal vein. Our knowledge of the causes of the formation of

TIIH I.IVEU.

703

piti'iiUMit in the liver cpilliclia is vci'v liiiiih'd, jiltlioiij^li sjx'cula-
tiniis on this jxiint tire nunicroiis.

\V<i.rii (h'l/cinrdfioii is likewise often observed in the liver-tissue,
jtrineipiilly in ])ersons who for vefirs Ix'fore death snffered fi'oni
exhaustinii' disease, sneh as syphilis, tuherenlosis, ne})liiMtis, pro-
fuse suppuration, etc. The increase in the size and weight of
sneh livers, and their larda(^eous appearance, are well known ; but
neither the cause nor the intimate nature of the waxy metamor-
phosis are understood. The microscope reveals that the e})ithelia
and the connective tissue are reduced into medullar}' corpuscles, or

'^^^7V )0''i

^^m^-^n

i

Fig. 315. — Waxy Degeneration of the Liver.

1>. bile-duct; C, interstitial counective-tissue, with plastids, partly unchanged, iiaitlj"
waxy ; JC, liver epithclia breaking down into medullary corpuscles ; ^V, liver epithelia in com-
I)lete waxy nietaniorplio.sis. Magnified 500 diameters.

the epithelia transformed into clusters, "with faint traces of medul-
lary corpuscles, before the infiltration with, or the transformation
into, waxy material takes place. Further studies are needed to
throw more light upon the natnre of this change. (See Fig. 315.)

Yellow Atrophy of the Liver. By J. A. Eockwell, New York."*

Dr. Heitzmann handed me for examination pieces from the livers of
two persons, exhibiting distinct signs of yellow atrophy. One of the cases

- "Microscopical Studies in Yellow Atrophy of the Liver." The Xew Emjand Meilical
Gazette, 1882.

704 THE LI V Eli.

was of an acute character, the person having died eight days after the first
appearance of jaundice ; while in the second case, two weeks before death,
severe symptoms characteristic of yellow atrophy set in, though the clinical
sjTuptoms for some time previous had been those of interstitial hepatitis,
with cin'hosis.

In specimens obtained from these two cases, a difference was noticed in
accordance with the clinical history. In the first ease all the evidences
pointed toward a very acute destructive process in the liver, without any
other complications: in the second case, the features pointed toward an
acute catan-hal or interstitial hepatitis, combined with those of yellow
atrophy. In fact, some observers have claimed that both these processes are
so far identical that yellow atrophy must be considered merely as a very
acute interstitial hepatitis. This \'iew. however, I cannot coiToborate.

Sections obtained from the first case, when brought under the microscope,
exhibited as the most striking featiu-e the want of calibers throughout the
portal system, the intra-lobular capillaries, and hepatic veins. The second
striking feature was the more or less marked reduction of the size of the
lobules of the liver. The third point was a partial engorgement of the
capillary blood-vessels of some lobules, combined with extravasation of
blood. The fourth point was the disappearance of the lobules and the trans-
formation of all the constituent tissues of the liver into a granular mass —
the so-called detritus. In addition to these points a fifth was present in the
second case, comprising the phenomena of acute interstitial hepatitis.

Whereas, in normal liver-tissues the portions between the lobules abound
in large veins belonging to the portal system, in yellow atrophy such vessels
are either invisible, or, if present, considerably changed in their aspect.
Portal veins, which were still recognizable as such, presented an iiTcgular.
seemingly jagged, bordering line suiTOuntling an angular, as if compressed
or collapsed caliber. This, instead of containing blood, held only a brown
granular mass, composed of shriveled, partly disintegi"ated blood-corpuscles.
The branches springing from siich portal veins were stretched to a naiTow
slit, which was bounded by medullary corpuscles, and, outside of these, by
the so-called structureless layer present beneath the endothelia in the normal
condition. The stretching of the vessels of the portal system to such a
degi-ee that their calibers were entirely lost, was observed in all places in
which the disease had reached a high degree, though still in its initial stage.
The former caliber was marked by the presence of endothelia, partly broken
down into medullary coi-puseles which were closely attached to each other,
and on either side was seen a somewhat denser tract of conuective tissue
corresponding to the walls of the vein. The capillaries exhibited the same
features ; most of them were compressed to such a degi'ee that the endothelia
of the wall touched each other. Such thoroughly compressed capillaries were
in communication with less compressed ones, filled apparently with detached
endothelia and medullary corpuscles, CAidently sprung from endothelia, and
with scanty red blood-corpuscles.

The interstitial tissue was everywhere augmented, and composed of a
large number of globular or in-egular elements, such as we observe in the
inflammatory process. But, while in simple acute inflammation the globular,
homogeneous elements composed of solid bioplasson are largely prevailing, in
yellow atrophy they were much less numerous, the finely granular bodies
being largely in excess. The latter are divided into lumps of small size.

Till-: LlVKi:. 70.")

showing, with hi^li jjowcrs of the microscope, a scanty reticulum of biojilassoii
in clusters, which are sej)arated from eacli other bvnaiTow, light rims, though
still interconnected by delicate, grayish filaments. In most places the tracts
of the former fibrous connective tissue could be recognized oidy by the rows
of such s)ilit-ui) medullary corpuscles.

The bile-ducts in the interstitial tissue were well preserved, still being
lined by columiuir epithelium, l)oth in longitudinal and transverse sections;
but their calibers were invariably compressed. Further changes of the epi-
thelia of the bile-duct consisted in the disappearance of the nucleus and in
the division of the ei)itlielia, partly into liomogeneous, shining, partly into
finely granular lumps, which, by their regidar arrangement in rows, reminded
one of their origin. At last, all differences between lumps sprung from con-
nective tissue, and those arisen from l)ile-duets, faded away.

The lobules of the liver were considerably reduced in size; in some places
to one-half, to one-third, to one-tenth of the former diameter. This was the
result of the transformation of the liver epithelia into medullary corpuscles,
as is observed in intiannnation generally. The gradual changes of the epi-
thelia resulting in tlais destruction were as follows : First, the nucleus becomes
invisible, due, as revealed by high amplifications, to its splitting up into a
reticnlum similar to that constructing the epithelial body. Next, the ledges
of cement-substance between the epithelia disappear, and a number of epi-
thelia coalesce into granidar masses containing a varjdng number of granules
and globules of fat. In this stage the rows of liver ei>ithelia are still seen.
With higher powers w-e recognize the granulation of epithelia to be due to
tlie presence of their bioplasson reticulum, which is very much more marked
than in the normal condition. This distinctness of the reticulum is due to
an increase of the size of the meshes and a scanty new formation of bioplas-
son within the epithelia ; in fact, coarse gi'anules of bioplasson, and homoge-
neous, shining lumps, are found in them exceptionally only. The next stej)
in the destruction of the epithelia is that within the cluster new lines of divi-
sion appear, dividing the clusters into numerous, irregiilar medullary ele-
ments, all of which are composed of rarefied bioplasson reticulum, and none
of which have a nucleus. (See Fig. 31 G.)

In some lobules, likewise decreased in size, the blood-vessels were en-
gorged and the interstitial tissue crowded with red blood-corpuscles. The
changes of the epithelia of such lobules were the same as before described.
As the engorgement of the capillaries and the extravasation of blood in some
places occupied quite extensive fields, I cannot help suggesting that what the
authors have termed "red atrophy" of the liver, combined with "yellow
atrophy," is due only to the engorgement of the blood-vessels and an extra-
vasation of blood.

In the highest degi-ees of the disease the lobules of the liver had entirely
disappeared, and, as a residue of the former liver-tissue, nothing was left but
an accumulation of medullary corpuscles, or particles of varying sizes, be-
tween which were seen small tracts composed of spindles, besides a varying
number of fat-globules. The most marked feature of this tissue was the
absence of new formation of liWng matter. Indeed, only a few larger lumps,
composed of a somewhat coarser reticulum of bioplasson, could be seen, while
the main mass was an aggi'egation of small lumps, indistinctly bordered by
light ijiterstices, and marked by the absence of nuclei and the presence of an
45

706 THE LIVEIi.

extremely rarefied bioplasson reticulum. The conueetiou of the lumps and of
the reticulum itself was Hoichfre hrol.en, so much so that this remnant of the
former liver-tissue still deserves the name of tissue, and cannot be called
detritus. Where the living matter of the constituent tissues of the liver, which
is so noticeably decreased in amount, has gone to, I am unable to say. Nev-
ertheless, I am positive that the reduction of the size of Jhe whole liver is
entii-ely due to a loss of its li\nng matter.

As before mentioned in the second ease which I examined, there were
marked features of acute interstitial hepatitis. The interstitial tissue in
some places was crowded with globular inflammatorj- corpuscles of a coarsely
gi'anular or homogeneous appearance, several of which were inclosed in a
mesh of a delicate fibrous reticulum. At the border of the lobule the stages
of transition of liver epithelia into medullary or inflamraatory corpuscles

-K'-

f

Fig. 31 G. — Yellow Atrophy of the Lh'er.

E, cluster of liver ei)itliflia with iudistiuct uuclei ; V. compressed rapillaiies ; B. cai>illarj-
engorged vritli red blood-coi7)U8cles ; Z, division of liver eiiitlielia into in'egular lumiis, with
a rarefied Ijiojilasson reticulum and a few fat-granules ; .S', accomplislied dLsintegration into
]>articles of vars'ing sizes, mixed witli red blood-corjiuscles. Magnified 800 diameters.

could be plainly seen. In other places the breaking down of the liver
epithelia proceeded nearly simultaneously from the epithelia of the lobule
left, with the result that, instead of shining, homogeneous, only finely gran-
ular, irregular medullarj- corpuscles were seen. The process was essentially
the same as in the first case, although of much less intensity, and there was
also present a more decided inflammatory new formation than in the first

riih: iJVKu. 707

i-aso. In till' interstitial tissur, I'xhibitint^ niaiUcd inllaniniatnry cliinif^t'H,
tliere were observed in some jilaces numerous hilc-ducts, wliilc in other
places these were entirely al>sent.

The results of these researehcs may Ix- sumincd up in the ioliowiiif^
statements :

1. YtUoir (ilni/ili!/ <-(i)i.^isf.s in llic linaLiiiff (Idiiii <>/ all (■o)i.ftit>iiiil rhiiioils <if
the liver into irrvijiihir Ik in /is <;/' intdnllari/ cloiifiits, acciiiiijXDurd hi/ a caii.sidmi-
hlr losf< »f liriiii/ matter.

'2. The disease has one feature in eoiiiiiion with injianiiiiation — i. e., the reduc-
tion of the eoiistitiieiif tissues into inflanniiatorji eorpiisetes ; hut the essential
feature if injlaiiiiiiation, naniehj, the new formation of lirinij matter, is absent.

3. Fattij dei/eneration is no eharacteristie sii/n of i/elloir atrojthi/, as in both
eases fat was jiresent onlij in a small amount.

4. There are eombinations of aeute eatarrhal or interstitial hejialitis with ijel-
low afrophi/, hut in what eausal relation to each other I hare not determined.

i"). I{ed atrojihy, combined with the yellow, is very probably due merely to a
partial eni/ori/einent of the capillaries and extravasation of Mood.

('). Most of the vessels helonijini) to the portal system of the liver heimj collapsed,
(he conclusion is admissible that the disease is due to an impeded circulation in
the lan/er portal ressels. The partial engorgement of the capillaries and the
extravasation if blood could be explained by an impeded circulation in the hepatic
artery.

One of the most recent writers, J. Dreschfeld,* gives the following sum-
mary of the present condition of this subject, briefly stating the main points
about which authors at present disagi*ee :

"(1) As regards the icterus, many believed it to be of the hepatogenic,
others believe it to be of the hematogenic kind.

"(2) While all are agreed that the chief lesion in the liver — whether
acute liver atrophy be considered a general disease (as most observers
believe) or primarily a local disease — consists in a fatty degeneration of
the liver-cells, some A\Titers {e. i/., Winiwarter, Wiener Mediz. Jahrb., 1872)
think that the first change consists in an inflammatory process in the inter-
lo])ular areolar tissue, which only secondarily causes fatty degeneration of the
liver-cells. Again, accoriling to Levitski and Brodowski (Virchow's Archiv,
vol. Ixx., p. 421), there is, prior to the cell-degeneration, a cell-proliferation
in some parts of the liver-lobules, these observers having seen numerous liver-
cells three to foiu- times smaller than the normal liver-cells in those parts of
the liver-parenchyma which had not yet undergone degeneration.

" (3) As to the relation of the red to the yellow atrophy, most patholo-
gists now believe that the red atrophy is only a more advanced state of the
yellow atrophy, and is foxmd in cases which run a slow course (Zenker, Perls,
etc.) ; wliile Klebs, on the other hand, believes the two to be essentially dif-
ferent processes.

"(4) The red atrophy is characterized by a more complete disintegration
of the Uver-cells, by the presence of an interlobular, embryonic tissue, and of
rows of cells resembling glandular tubes, supposed by some to be proliferat-
ing biliary ducts (Cornil and Ranvier), by others to be the surviving columns
of hepatic cells (Thierfelder, in Ziemssen's 'Cyclopedia,' vol. ix. , -p. 254).

"On the Moiliid Histology of the Wvev in Acute Yellow Atroiiliv." Jour. Anat. and
Physiol., Loiul., lSSO-1, xv., 4'22-4«0.

708 THE LIVEB.

•'(5) Lastly, some observers (Waldeyer, Zander) have discovered bacteria
in the atrophied liver. (In Zander's case, however, the autopsy was not per-
formed nntil fifty-eight hours after death.) "

In 1S54 and 1862 H. Lebert * gave a careful analysis of seventy-two
cases, together with an abstract of the literature of acirte yellow atrophy
from 1660 to 1862.

This subject has since been treated at length by A. Thierfelder, t who
brings down the discussion to 1877. I have examined twenty-eight con-
tributions piiblished since this date, which, with the exception of that of
Dreschfeld, I find to consist chiefly of clinical reports.

Vircliow's Aicliiv, 1854, vii. 343 ; "Archives G6n6rales de Me<l.," 1862, i., 431.
i Ziemsseu's " Cyclopedia," American edition, ix., 254.

XVIII.

THE RESPIRATORY TRACT.

THE fimctiou of the respiratory^ tract is the exchange of gases,
mainly carbonic acid gas for oxygen, and for this purpose
there is free access of the atmospheric air to the hmgs hy means
of tnbuhir formations. The nasal cavities mnst be considered as
the beginning of the respiratory tract, although the oral cavity
can serve for the same purpose. While all cavities and canals
of the body, when at rest, are closed by folds of the mucosa, the
cavities and passages engaged in the respiratory function are
open either by means of the surrounding bones and cartilages
such as the nasal cavities, or by cartilages alone, as the larynx,
trachea, and the bronchi. The lungs themselves, where the
gaseous exchange takes place in all higher developed animals, are
kept in open communication with the outer world by the elastic
tissue, which is present in large amount in the walls of the
alveoli. The lung contains aii-, " residual air," from the first
inspiratory movement of the newly born child, the amount being
merely augmented by inspiration and lessened by expiration.
In the foetus, before birth the alveoli of the lungs are closed, and
such lungs are called atelectatic. The same condition is pro-
duced by the choking of the alveoli by the products of inflamma-
tion, or a transformation of the lung-tissue into solid connective
tissue, or by the pressure of exudate in the pleural cavity. The
capillaries, like all structures of the lungs, are developed before
birth, but l)ecome filled with blood only after the first insi>iratory
movement.

(1) The two sides of the nasal cavity are divided into a resph-a-

710 THE BESFIBATOliY TILiCT.

tovji and an olfacfori/ ])()rti()n. At its beginning the wall of the
nasal cavity has the same structure as the skin. It is freely sup-
plied with hairs and sebaceous glands, and covered by a stratified
epithelium. Behind the pyriform aperture the stratified epithe-
lium is changed into columnar, ciliated epithelium, whose cilia are
directed toward the choauae. The connective tissue producing
the mucous layer is abundantly supplied with acinous glands,
which produce a serous secretion. Toward the upper narrowed
olfactory portion of the nasal cavity the ciliated epithelia disap-
pear and are replaced l)y simple columnar epithelia.

In the lateral cavities, which are in connection with the nasal
cavity, the thin mucosa is covered with ciliated exjithelia, but the
acinous glands are very scanty. According to E. Zuckerkandl,
in the upper waU of the maxillary sinus there is a tongue-shaped
portion of the mucosa, richly supplied with glands; this portion
is characterized to the naked eye by a pale yellow color. The
mucosa of the nasal cavities has an abundant vascular supply, the
veins being wide and united into a plexus. On the convex surface
of the concha, more particularly at its posterior extremity, the
veins produce a cavernous tissue (Henle). In the lateral cavities
the blood-vessels are far less numerous.

The olfactory portion of the nasal cavity is, according to M.
Schultze, limited to its roof to the upper turbinated bone, except
the lower border, and to the upper portion of the septum narium.
This portion is characterized by a yellowish color, the mucosa
being broader than in the respiratory portion, and freely sup-
plied with nerves and tubular glands, and, as a rule, also with
clusters of brownish pigment.

The epithelial lining attains, in this situation, a considerable
size, and, as M. Schultze discovered, is composed of columnar
epithelia, between which are lodged the olfactory epithelia. The
latter consist, according to him, of a fusiform, nucleated body,
occupying the lower portion of the epithelial row, with polar
prolongations of varying lengths. The peripheral offshoot ex-
hibits varicose enlargements, and in many animals holds on its
surface delicate cilia, which have no analogue in man. The
central offshoot has the features of non-medullated nerve-fibers,
and very probably is in direct union with the terminal branches
of the (non-medullated) olfactory nerve. The feet of the col-
umnar epithelia proper exhibit pencil-like ramifications, serving
for their attachment to the subjacent connective tissue, and are
often supplied with brown coloring matter. According to S.

rill': ]:h'si>ii:.{ i()i,-y rnAcr. 711

Exner, there is no essential (litit'erence ))et\veeu the colunuuu' anil
the olfactory epitlielia, whieh exhil^it forms of transition, the
retieuhir hiyer at the ])()ttoni of the e])it]ielia beinj^ (h'stined for
tlieir indirect connection with the terminal fibers of the olfac-
tory nerve. The tnbular giands (Bowman), which 'occupy the
whole 1)readth of the mucosa, are said to be lined by columnar
epitlielia.

(2) The Ittri/Hx is composed of a cartilaginous frame, which
serves for the attachment of the striped muscles and the mucosa
throuiih the intervening- i>erichondrium. Most of the cartilages
art' hyaline, but freely intermixed with fil»rous, es{)ecially in
the iniddle portion (see page 206, Fig. 79). The epiglottis, the
supra-arytenoid and cuneiform cartilages are composed of retic-
ular cartilage, and this variety is also, as a rule, found in the
processus vocales of the arytenoid cartilages. The cartilage of
the epiglottis is in several places divided by fibrous tracts, con-
taining a few l)lood-vessels, and in its laryngeal surface excava-
tions are seen for the reception of large mucous glands.

The mucosa of the larynx is either uniformly composed of a
loose, fibrous connective tissue, or of dense fibrous tissue near
the surface (vocal bands), and loose submucous tissue in the
deeper portions. Both are freely supplied with elastic fibers,
which are especially developed in the mucosa of the vocal bands.
In the latter situation longitudinal bundles of smooth muscle-
fibers are intermixed with the connective tissue. The submucous
layer contains large quantities of lymph-tissue, more abundant
in children than in adults, although in the larynges of the latter
we find tissue of this kind in the mucosa covering the ventricles
and the ventricular folds. In addition, a varying amount of
fat-globules is also observed in the submucous tissue.

The papillae of the mucosa of the larynx are very small, and
it is only at the glossal surface of the epiglottis and in the
region of the arytenoid cartilage that they are more marked.
Along the posterior wall of the larynx, and on the ventricular
folds, the mucosa is duplicated into elevations, which are often
mistaken for papillge.

At the glossal surface of the epiglottis the epithelial cover is
broad and stratified, and supplied with formations similar to
gustatory l)uds. The stratified epithelium gradually decreases
in ])readth after passing over the edge and the laryngeal surface
of the epiglottis. Toward the lower third of the latter it is
clianged into ciliated columnar epithelium, which lines the

712 THE liESFIBATOliY TBACT.

whole inner surface of the larynx, except that, over the vocal
bands, delicate stratified epithelimn is seen, which is most marked
in the middle portions. Here, at the boundary of the connective
tissue, a narrow, so-called hyaline layer is also noticed, which is
found in no other portion of the mucosa of the larynx.

The ei>ithelial cover passes, with numerous prolongations,
into the connective tissue, forming- acinous glands. These appear
as extended, fiat layers underneath the mucosa covering the vocal
bands ; while they constitute more or less globular formations
in other portions. The largest mucous glands are found, as a
rule, at the lower portion of the laryngeal surface of the epiglot-
tis and along the posterior wall of the larynx.

The blood-vessels in the mucosa of the larynx are expanded
into several flat layers, and in some places we can distinguish three
such layers, whose meshes become narrower near the surface.
The largest veins are found in the mucosa covering the posterior
wall. The Ij^mphatics also produce two indistinctly marked lay-
ers, the meshes of the upper layer being narrower than those of
the lower. The nerves are said to be supplied with numerous
ganglionic elements.

(3) The tracliea is a rigid, elastic tube, composed of incomplete
cartilaginous rings, w^hich, at the posterior wall, are closed by a
layer of fibrous connective tissue abundantly supplied with elas-
tic substance. The cartilage of the tracheal rings is hyaline, but
in the middle portions fibrous, similar to the laryngeal cartilages ;
the fibrous structure being more marked in adults than in chil-
dren. The mucosa is in close connection with the perichondrium,
and has a nearly uniform composition of delicate, fibrous con-
nective tissue, scantily supplied with lymph-tissue, but with an
ample supply of blood-vessels, among which wide capillaries and
veins are the most marked. Nearer the surface a delicate layer
of smooth muscle-fibers is found, arranged usually in a circular
direction. In the posterior wall, at the places where the cartilage
is lacking, the circular muscles produce a broad layer, uniting
the blunt ends of the cartilage, and on the peripheral portion of
the posterior wall large longitudinal muscle-bundles are found.
The mucosa of the trachea is destitute of papilla^, l)ut lies in folds
along the inner circumference. If these are well nuirked in the
anterior portion, then the posterior portion, where the cartilage
is absent, is without folds. The innermost layer of the con-
nective tissue produces a delicate basement-membrane, which,
however, is not invarial:)ly present in all trachea^. (See Fig. 317.)

Tin-: in:si>iu.[ louY tuact. 71:3

Tilt' liiiiii*!: f'pitlu'liuiii is of tho ciliated rolimniar variety,
indistiiu-tly stratifieil — tlif cilia beiiij^ directed, as in the larynx,
toward the throat. Its prolongations form racemose mucous
glands, lying in flat layers close above the j)erichondrium, and
glol)ular formations in tlie posterior wall: in the latter situation
they are especially large and numerous. Tln-ir ducts traverse the
mucosa in an oblique directicju, and are lined by columnar epi-
thelia, which, near the opening at the surface, are supplied with
cilia. Similar features can also l)e observed in the bronchi.

(4) The h(n(j.s are composed of minute cfUs or (tlveoli. which
are inclosed by fibrous connective tissue, a group of alveoli being
connected with a bronchiolus or alveolar duct. This union of
cilveoli and alveolar duct is called a lobule, the general .shape of
which is conical, \\itii the base directed toward the periphery of

Fi«i. 'Ml. — Trachea of a Child. Traxj^verse Section.

E, ciliated coliiinnar eiiitheliiiiii ; .V, hyaline or baseinent-la.ver : F. fibrous coiiuecti vi- ti.-ssui-
of the mucosa; .V, circular bundles of smooth muscle-fibers: Jj, Xi, ducts of mucous "lands, in
longitudinal and transverse .section; G, racemose mucous glands; P, perichondrium : C, hya-
line cartilage. Ma^rnified 200 diameters.

the lung, and its apex connected with a bronchiolus. This rela-
tion is most marked in the peripheral portions of the lungs.
The terminal alveoli bear the superfluous name " infundibulum."
The widening of the bronchioli into the lung-cells is abrupt, and
single cells, or cells arranged in small groups, may be seen
attached to the bronchiolus before it terminates into the lobule.
The lobules are separated from each other by a broader layer of

714 THE RESPIEATOBY TRACT.

couuective tissue, and the polygonal fields thus produced are
distinctly marked on the surface of the lung.

The bronchi having subdivided at acute angles, the carti-
laginous rings gradually disappear, and in the small bronchi
are reduced to a few irregular plates. The muscle-layer, on the
contrary, increases in size, and the smaller bronchi exhibit a
very distinct cii'cular layer of smooth muscle-fibers. The finest
bronchi have only scanty cii'cular muscle-fibers. The fibrous
connective tissue composing the terminal bronchi is freely sup-
plied with elastic substance, and so long as the bronchi course
between the lobules they are attached to the lobules by loose
connective tissue, having a capillary system of its own. The
hyaline basement-layer is more marked the finer the bronchi,
and is covered by a stratified columnar, ciliated epithelium. In
the bronchioli of less than 1 mm. diameter, the stratification of
the epithelia is nowhere marked, though they remain ciliated to
the point, where the bronchiolus (alveolar duct) widens into the
alveoli of the lung. The columnar epithelia gradually decrease
in height, and finally blend with the flat, non-ciliated epithelia,
covering the inner surface of the alveoli. All bronchi are sup-
plied with acinous mucous glands, which are located above the
muscle-layer, and become fewer and smaller as the bronchi
decrease in size. In the bronchioli only simple acinous glands
are found, which disappear altogether when the bronchiolus
enters a lobule.

Each lobule of the lung is composed of a number of alveoli,
which are semi-globular protrusions, separated from each other
by folds or septa of connective tissue. The septa, together with
the delicate inclosing connective tissue, constitute the wall of an
alveolus. The connective tissue is marked b}' a rich reticidum
of elastic fibers. The separating folds are never entirely effaced,
even in an expanded lung ; though by the inspiratory act they
become more shallow, as is demonstrated by the examination of
lungs, into the aerial passages of which aii' or gelatine had been
injected before hardening in chromic acid.

The vascular supply of the lungs is very abundant. The
arteries which carry the venous lilood are characterized by their
straight course ; while the veins which carry the arterial blood
have an irregular, slightly sinuous appearance. Both accompany
the bronchioli, the arteries being surrounded, besides the mus-
cle-layer, by a marked adventitial coat of fibrous connective
tissue. The bronchi have an independent system of blood-

'////•; i:j:si'/i;a JoiiY ihact. 71.')

vessels, tlcstiiu'd also for the iiuti-itioii of the adventitial coat
of the lar»;t'r blood-vessels; their capiilarit's, however, inosculate
with those of the alveoli of the lun^.

The branches of the pulmonary artery, upon reachinj^ the
lol)ules, rapidly <lecrease in diameter, and supply the alveoli
with a rich reticulum of ca})illarv blood-vessels, which is located
directly underneath the fitit, alveolar epithelium, and is often
seen, toward the central space, rising above the level of the

Fig. 318. — Lung of Max. Blood-vessels Injected.

A, iiulruouary .iitfi-y ; C, cipillaries of the alveoli ; IJ', walls of tlie alveoli ; Ji, bronchus,
in transverse section. Magnitieil "200 diameters.

alveolar wall. In such bulging- portions the endothelia of the
capillaries are ea»sily discerned. (See Fig. 318.)

In sections made through injected and hardened lungs, the
walls of the alveoli are marked by the presence of the pre-
capillary, arterial, and venous vessels, and by an apparently
more abundant reticulum of capillaries. Some of the alveoli
exliil>it the capillary reticulum in parts or throughout their

71 () THE UKSPIUATOUY TRACT.

entire extent, while other alveoli appear empty. Both these
conditions become intellio-ible if we bear in mind tliat the blade
of the knife passes throug-h some alveoli near theii- periphery,
and through others across their centers ; the former will show
the capillaries in front view, in the latter none at all will be
visible. The thickening of the capillary j-eticulum along- the
walls is due sim])ly to their optical shortening in the top view of
the septa. If we look into a basket, the bottom gives the hurdle-
work in front \4ew, therefore extended, while the walls show the
hurdle condensed, and thus the wall appears thickened. By this
simUe the structure of the lung iH'Comes easily understood.

Upon applying: the high powers of the microscope, we
recognize the broad capillary reticulum at the bottom of the
alveoli, while the same reticulum appears shortened and con-
densed along the septa. Close above tlie blood-vessels we see the
extremely delicate layer of flat epithelia, which has often the
appearance of a granular mass with regidarly interspersed nuclei,
while the eement-sulistance is not plainly marked. The injection
of a solution of nitrate of silver brings into distinct view the
dark brown lines of the cement-substance, interrupted by delicate,
transverse light lines, which correspond to the connecting fila-
ments (thorns). F. E. Schidze discovered two varieties of lung-
epithelia, viz. : small, coarsely granular, and large, pale, nearly
homogeneous bodies; this ditference is marked only in those
human lungs which have been engaged in respiration. Henle
maintains that the epithelium cannot be seen in human lungs ;
but there is no difficulty whatever in observing it even in
injected specimens. (See Fig. 319.)

Neither lymphatics nor nerves seem to be very numerous in
the lungs, and neither the origin of the former nor the termina-
tion of the latter are yet explained. Some authors assert that
the lymphatics of the lungs are mere clefts in the connective
tissue, without any walls of their own. As we know that the
lymphatics everywhere constitute a closed system of vessels, with
an endothelial lining, contrary assertions, especially regarding
the lymphatics of the lungs, unless clearly demonstrated, deserve
little attention. The ultimate terminations of the nerves have
not yet been discovered.

Fdfhology. In autopsy the lungs of adidts are seldom found in
a perfectly normal condition. Besides the hyperfemia which
accompanies fatal diseases, serous effusion, called a'denut of the
Jhikjs, is often met with, representing a secondary and coneomi-

////•; in-.si'iuAKiitY iiiAcr. 717

taut condition of (litlcrciit disfiisi-s which tcnuiiuitL' fatally. In
mieroscopiral examination of .specimens of hmjjs hardened in a
solntion of chromic acid. oMh'imi can l)c diau:nosticatcd l»y an
eny;or<rcmcnt of tlic capillaries with blood. ])y a .sli<:!fiit enhirj^e-
ment of the intn-stitial connective tissue, dne to the saturation
with a serous li(iui(l. without marked intlannuatory clniuires, and
hy the pivsenee of a finely granular mass, the coafi'ulated sero-
alV)umiu()Us li(inid within the alveoli. In this uuiss are imbedded
a comparatively small number of red })lood-cor])Useles of l)io-
plasson bodies, which are pro))ably emi^'i'ated colorless ))h)od-

FiG. 310. — Alveoli of the Lung op Max. Blood-vessel.s
Injected.

A, alveolus ; I', puiiiioiiaiy vt-iii, sprung from the union of the (apillai y rctiiuhun ; ir.
•wall of the alveolus ; A". Hat cpitlielia, coveriug the Inner surface of the alveolus. Jla^uitieil
500 ilianieter.s.

corpuscles, and detached epithelia of the alveoli, which are
swollen and ])artially dropsical.

Pi(jineittafio)t of the Innys is never found in newl}' born
children, but is marked in proportion to the exposure of the indi-
vidual during life to a smoky or dusty atmosphere. The lungs of
tobacco-smokers and coal-workers show high degrees of black
pigmentation, which gives the tissue a peculiar variegated
appearance. The lungs of laborers in coal-mines, in iron foun-

718 THE liESPIliATOJtY THACT.

(leries and in l)ras.s foniuU'rifs. all show differences in color. The
pigment in the alveolai- epithelia consists of minute black gran-
ules, and in the interlobular connective tissue it is present in
clusters. The l)ronchial lymph-ganglia are found jet-ljlack in
persons with pigmented lungs, owing to the coloring matter
carried into the lymph-tissue from without. There is no founda-
tion, however, for the assertion that such an accumulation of
pigment causes serious diseases of the lungs, although it is
unquestionably a morbid condition.

Emphysema is another morbid condition of the lungs of very
frequent occurrence. It consists in a mere dilatation of the alve-
oli,— vesicular emphi/sema, — or in a rupture of the septa and a
union of a number of alveoli — JohuJar emphysema. It is caused
by forced inspiration and impeded expii-ation due to obstructions
of the air-passages, and their consequent dilatation by coughing,
in chronic lar^Tigitis and bronchitis. Emphysema is found most
commonly along the anterior borders of the lungs. The over-
distention of the alveoli gradually leads to a loss of the elasticity
of the waU, and to a permanent dilatation of the alveoli. In
higher degi-ees there is a rupture of the distended septa without
haemorrhage, as the blood-vessels become obliterated before the
rupture takes place. Higher degrees of emphysema invariably
lead to h^•])ertrophy of the heart, interstitial hepatitis, and
catarrhal or croupous nephritis, with general anasarca and fatal
termination. (See Fig. 320.)

Iniiammation of the hniy (pneumonia) appears in two principal
varieties: croupous or fibrinous or lobar pneumonia, and catarrhal
or lobular pneumonia. The former involves, nearly uniformly and
in a comparatively short time, large portions of the lung-tissue,
whole lobes, or the entii-e lung ; the latter is located in single
lobules or in groups of lobules, and runs a more protracted
course. Children under five years of age are very rarely affected
with croupous pneumonia, but the catarrhal form is of frequent
occurrence in early life. Under the microscope the distinguish-
ing features are as follows : In croupous pneumonia the intersti-
tial connective tissue is not markedly changed or increased ; the
alveoli are slightly distended and filled with an interlacing coag-
ulum of fibrine, in which are entangled red blood-corpuscles,
inflammatory corpuscles, and detached alveolar epithelia in vary-
ing numbers. In catarrhal pneumonia the interstitial tissue is
increased and crowded with inflammatorj' corpuscles ; the alveoli
are distended by a finely granular, albuminous exudate, contain-

•/•///•; h'Hsrih'Ai ()]{)■ ih-Acj'. 719

iii^' larp' (iiiantitics of iiiflaininatory corpuscles and detached
alveolai' epithelia, whicli exliil)it features of an eiido<i('iious new
formation of pus-cor])uscles. A third variety is tin* jtlnsfir iiiier-
sfifidl /)tirKni()ni<(, which is confined to the interstitial connective
tissue, and which hnids eitlier to cin-hosis or to Injpertrophj of
the hinji:s. A fourth variety is represented by the destructive
jturulcnf jmeinnoiiid, which appears either as a uniform infiltra-
tion of lar^e portions of the lung-tissue, or in the shape of
abscesses.

fa J Croupous rneuinoHtn. The most striking feature of this
variety is the sli£';ht change in the interstitial connective tissue —

Fig. 320.— Emphysema of the Lung. Blood-vessels In.iected.

A', K, imcliaiiged alveoli: I>, D, ililated alveoli; F, F, niptuied alveoli; T', puliuonaiy
vein. Majriiilied 100 lUameters.

the blood-vessels are engorged with blood; nevertheless, the
Avails of the alveoli are only little broadened. If we consider the
enormous quantity of inflammatory corpuscles present in the
alveoli, the conclusion becomes admissible that the majority of
the inflammatory corpuscles are emigrated, colorless blood-cor-
puscles. It is not probable that either the connective-tissue
frame or the detached alveolar epithelia could, in so compara-
tively short a time, produce such quantities of exudation corpus-

r2u

THE BESPIRATORY TRACT.

eles. In the initial stages of croupous pneumonia, or in its
milder fonns, — the so-called flahbtj hepatization, — the pathologi-
cal changes are best observed. See Fig. 321.)

Red Jiep((tizatio)i, nnder the microscope, is characterized — in
addition to the engorgement of the blood-vessels — by the presence
of numerous red blood-corpuscles in the exudation plug, which is
found to consist of a var^^ing amount of coagulated fibrine
closely attached to the wall of the alveolus. In the progress of
pneiunonia a great many capillaries are destroyed, for the nearer
the process approaches to f/ra>j liepatizntion. the fewer are the

Fig. 321.— Croupous Pneumonia. Blood-vessels Injected.

ir, -wall of alveolus ; witli the coagulated felt-work of fibrine filliujr the alveoli are entau-
gled R, red blood-corpascles ; C, inflainniatoiy corpuscles (emifrrated, colorless blood-coi-pus-
cles .'1 : -£■. detached epithelia of tlie alvcnli. Mairnified 500 diameters.

capillaries discernible iu the alveolar walls, while those that still
remain are very much distended, without being engorged by red
blood-corpuscles. The gray color of the lung-tissue is largely
due to this loss of capillaries. The plugs in the alveoli are found
the more uniformly detached fi-om the alveolar wall, the farther
the pneumonia has advanced toward gray hepatization, and in
the plugs composed of exudation-corpuscles no coagulated fibrine
is discerned. With the new formation of capillary blood-vessels

/•///•; liHsl'lllA lOHY Tit ACT. 721

and the iTt''stal)lishiiu"Ut of the circulation, the disease terminates
in recovery, manifested l)y the complete throwing off of the
|)ln<is, which ai"c saturated witli liipiid exudate, and thus
loosened.

Sometimes in persons of a moderately good constitution, in
lol)ar pni'umonia exhibiting all features of croupous inflamma-
tion, the li))i-inous exudation is scanty and the alveoli contain
maiidy an albuminous mass holding numbers of inflammatory
corjjuscles. In such cases there is sometimes no reforination
of the blood-vessels destroyed in the pneumonic process, and
the tissue, then deprived of nutriment, becomes firm and gray-
ish yellow, and finally changes into a yellow, cheesy, crumbly
mass. This represents the so-called cheesfj pneumonia, which
is identical with tuberculosis, although oi'iginating in larger
districts of the lung-tissue and under more marked inflamma-
tory symptoms than tuberculous foci in general. In cheesy
])neumonia, the existence of which is marked b}' the c<nitinuance
of the physical signs of pneumonia with the so-called '' hectic "'
fever, the interstitial tissue is transformed into inflammatory
corpuscles the same as in catarrhal pneumonia, and by this pro-
cess in turn most of the blood-vessels are destroyed. The alveoli
are filled with an inflammatory tissue which had its origin entirely
in the alveolar walls. In these the elastic substance resists the
inflammatory process in most, but not in all cases, and in more
advanced stages of the disease numbers of inflammatory cor-
puscles are shriveled, owing to the want of the nourishing blood-
vessels, and torn apart or disintegrated, while the elastic frame
of the former alveoli is still recognizable. Shriveled inflam-
matory corpuscles always exhibit irregular outlines, a fine granu-
lation, and pale nuclei, owing to a deficiency of living matter
which characterizes the phthisical constitution of the patient. The
<;onibination of these appearances produces the cheesy, crumbly
or tuberculous mass. A liquefaction of the mass is possible
only in localities where the neighboring blood-vessels had, at
least for a time, escaped the inflammatory destruction. Fatty
degeneration is, as a rule, combined with the cheesy metamor-
phosis, as indicated by the preseuce of crystals of fatty acids.
(See Fig. 322.)

A third and very rare termination of cr(nipous pneumonia

consists in the hroivn Jiep((fi2(tfioii of a lobe. This condition is

due to a new formation of interstitial connective tissue, scantily

.supplied with blood-vessels — i. '\, hvpertrophv of the lung-

46

I'S^

THE BESPIBATOBY TRACT.

tissue, with profuse pigmentation of tlie newly formed tissue, the
pigmentation being probably caused by an incomplete develop-
ment of red blood-corpuscles or hamiatoblasts.

Hifpofitatic ptieumoiiia is the consolidation of the pendent portions of the
lung toward the end of life. It consists in an engorgement of all the blood-
vessels, a sero-albumiuous exudation, and a profuse detachment of the alveolar
epithelia. The latter and a var,\-ing amount of red blood-corpuscles and
exudation corpuscles, which in all probability are emigrated colorless blood-
corpuscles, compose the plug choking the alveoli. The interstitial tissue
takes no active part in the process.

(h) Cuturrhal pneniiionid. The most characteristic feature of
this fonn is the intiammatol•^• new formation in the interstitial

Fig. 322. — Cheesy Pxeumoxia, or C'hroxic TrBERCULOsis

OF THE LUXG.

E, elastic frame of the forruei- .alveolar walls ; .S', slnlveled inflaiuiiiatory corpuscles and
iri-anular detritus ; M, so-called margaric acid crystals. JIajruilied .500 diameters.

connective tissue. The alveoli are filled with an albuminous
exudate, holding inflammatory corpuscles, produced in part by
the proliferation of the connective tissue, in part l\v an endo-
genous new formation in the alveolar epithelia ; to some extent
they may also be due to an emigration of colorless blood-corpuscles,
which occurrence is possible so long as the blood-vessels are not
destroved. With a new formation of tlie lost l)lood-vessels cure

THE liKsi'iuAiuhY jn.icr.

723

will (.Misuc. If, on the contrary, the inflannnatory tissue-like
new formation wliieli fills the interior of the alveoli h{' entirely
deprived of its nutrient alveolar blood-vessels, a tubercle will l)e
the result, corresponding- in size with the av'ascidar loljular dis-
trict. This is the most common ternnnati(ni of catarrhal pneu-
monia, and is almost inevitable in })ersons<tf a poor constitution.
iSee Fig. 823.)

So long: <is the inflammatory corpuscles remain interconnected
by delicate filaments — /. f., remain a tissue — small districts, not-
withstanding- the lack of blood-vessels, may become supplied with
l)asis-substanee similar to that of cartilage, the so-called horny

VF

Fig. ;J23. — Catarrhal Pneumonia of a Child, Changing

TO TrBERCULOSIS.

I'F, iincli;inK(!<l wall of alveolus; //', wall of alvoolus crowded with inllaiiiinatory cor-
imsclcs: C, alveolus filled with coagulated albuiuen, iuflaniiuatory corpuscles, audi', detached
alveolai- epithelia ; X>, cluster of iiiWaiuuiatory cori)uscles, iu coiunieuciiijr shriiikajre. Mag-
nified 500 dianietei-s.

metamorphosis or obsolescence of the tubercle. As soon, on the
contrary, as the connection of the inflammatory corpuscles is
broken, and the inflaniniatory new formation ceases to be a
tissue, the corpuscles will shrivel, in part become disintegrated
— in short, undergo the " cheesy " metamorphosis. In the sur-
rounding lung-tissue, which is still provided with blood-vessels,
a new formation may ensue, resulting in the production of a

7l'4 the liESl'IllATOUY Tit ACT.

fil)r<>us capsule. Tims the eheesy focus is encysted, and maj'' be
rendered iniioeiions by fatty nietaniorpliosis and subsequent cal-
eifieation.

Saturation of the cheesy focus with a sero-albuminous exu-
date from tin* surroundini>' inflamed tissue will lead to the
formation of a tul)er(ndous cavity, the size of whicli will at first
correspond with that of the original cheesy focus, while after-
ward the cavity becomes enlarged by similar inflammatory
changes in the surrounding capsule itself, which result in the
formation of cheesy foci, presenting all the appearances minutely
descriljed in the chapter on tuberculosis.

A complete cure of the tubercle is effected by a i)rofuse new
formation of connective tissue in its neighborhood, with the
result of a dense, fibrous, cicatricial callosity. This termination
of the original catarrhal pneumonia is known by the term cirrhosis
of the lumj. Large portions of lung-tissue, usually of the apices,
are thus transformed into solid fibi'ous connective tissue, more
or less pigmented, according to the amount of pigment present
in the lung- tissue before the start of inflammation. In the cal-
losity are inclosed compressed alveoli of the lung and cheesy
foci in a more recent process, and calcareous nodules in an older.
The latter represents, as a matter of course, a cure. The cal-
losity is always marked by scanty vascularization. If, on the
contrary, a new inflammation ensues in the callosity — subacute
tuberculosis — with a complete loss of the blood-vessels in a cer-
tain portion, this will become a tubercle, and the process will,
though slowly, advance to destruction of the lung-tissue. This
is the reason why, in cirrhotic portions of the lungs, all stages
of tuberculosis may be found, both those tending toward a
cure and those tending toward ulcerative destruction. (See
Fig. 324.)

Acxfc iitiVKO'ii fnbcrriilosis is an inflammatory process, just as
is chronic tul)erculosis. No positive proofs have yet been fur-
nished that miliary tubercles originate from embolism of vascu-
lar districts of the lung-tissue, although such an embolic process
is highly probable. In the earliest stages of the formation of a
miliary tubercle we observe all the characteristic features of
catarrhal pneumonia. The smallest so-caUed sub-miliary tubercles
are inflammatory foci, involving only a few alveoli ; while larger
tubercles originate from a coalescence of a number of solidified
alveoli. In the early stages of the inflammatory infiltration the
elastic fibers of the alveoli mark the boundaries of the alveoli.

I UK UKsi'iK. I Kfu y rir i < r.

Tl^

while later cvt'ii the elastic fibers are destroyed l»yli(|iiefaeti()ii of
th<*ir basis-su})staiiee. The most characteristic featui-c of tiiis
condition IS the absence of l)lood-vessels within the tubercle. In
injected specimens we observe a small luimber of capillaries
entering: the most peripheral zone of the tubercle, while aiY>und
it the blood-vessels remain intact, and simply overlap the nodule.
In its nei<i;hl)orhood emphysematous alveoli are often found.
(See Fijr. :J2r).)

With hi»»lier am])lifications of the microscoj)e we notice in the
tubercle a mass of intiamnuitory corpuscles with an extremely
delicate myxomatous reti<-ulum. The corpuscles ai'c character-

Fi(i. ;324. — Cirrhosis ok the Lung, Caused by Subacite

TXJBERCULOSIS. BlOOD-VESSELS INJECTED.

A, c(HIlp^es^^<•(l alveolu.s: /. acute inrtaiiiiuatoiy iuftltrati<>ii of the interstitial tissue: F,
newly formed, fibrous (cicatricial) connective tissue ; C, scanty bloort-vessels. Magnitied
."ifM) diameters.

ized l)y a fine granulatiou — /. e.^ they are supplied with a little
living matter only. In the central portions of the tubercle mul-
tinuclear bodies are often found, the origin of which is not fully
understood.

(<•) Plastic rnterstifial pneNnionia consists in the new formation
of interstitial connective tissue, which leads to an enlargement of
the alveolar walls, with a decrease of the number of the blood-
vessels. This process is very common in insufficiencies of the
valvidar apparatus of the heart and stenosis of the arterial ostia.

726

THE liESFIRATCmY TRACT.

wliicli is followed by stagnation in the vessels of the lungs.
HYi)ei'tro]»hy or hyperplasia of the lungs is often connected with
emphysema. The new formation of connective tissue is well
marked around the larger blood-vessels, both arteries and veins,
more especially around the former. A rust-l)rown pigmentation
is, as a rule, found in the augmented connective tissue, evidently
due to a former extravasation of blood. (See Fig. ;{2().)

PV

Fio. 'A-2~). — Acute Miliary Tuberculosis of the Lung.

F, iiiiliaiy tiiberctle; CA. compressed alveolus ; DE, detached epitlielia of tlie alveolus: A",
euipliysematous alveoli : C, capillaries overlappiufc tlie tubercle; I'V, puluiouaiy vein, ilair-
nified 100 diameters.

(d) Suppurative pneumonia invades either the whole or large
portions of the lung-tissue in a manner similar to that of croup-
ous pneumonia ; or it appears in scattered foci, caused by embol-
ism, in pytemia. The distinguishing feature under the microscope

Till-: h'h'Sl'lh'.llOh'Y lUACI.

727

is tlir iiiiifoi'iH iiilillriitioii of the iiitcistil ial ('<)iiiH'ct ivc tissue
with iiit1;nmii;it<>i-v cnrpnscles, together with the i)lugging of
the caliluTs of tlic alveoli, as in ei-oupous piieiiinoniu. The
l)loo(l-vessels are eompletely destroyed, and in nioi-e advanced
stages the walls of the alveoli disai)pear entirely. The breaking
apiirt of the infiamniatory eor])useles leads to the formation of
pus. In pnndent pnennu)nia the whole invaded portion assumes
a grayish-yellow color, while in eirenniserihed snjjjuiration the
forming abscess is siUTounded by intensely hypenemic lung-
tissue.

Fig. 32G. — Hypertrophy and Emphysema of the Lunu.

F. broaileiied fruiiie of alveolus : E, einiiliysematoiis alveolus ; U, dftached alveolar epi-
thelium ; T, colloiil corpuscle, probably sprung from alveolar ei>itlielia : i*, i>ulniouary artery,
with a eoiisideraldv tliickenetl adveutitial eoat. Mairiiifietl 500 diameters.

Syphilitic Hepatitis and Syphilitic Pneumonia.
By J. H. Ripley, M. D.*

Mrs. B., the mother of eight chihlren — only one living, a boy of six, who
ha.s syi^hilitic incisor teeth — has had three successive miscarriages at the
eighth moTith of utero-gestatiou. The first two of these infants were still-
born ; the third, the subject of my examination, lived about fifteen minutes,
and even cried aloud.

The jiost-worti'Hi examination included only the thoracic and abdominal
organs, and was made in great haste. The lungs were large, of a dark grayish

Printed from the author's manuscrijit.

728 'I'lIK RKSI'lHATOJtY TJiACT.

color, film, and only slij^htly crepitant on pressure, the upper lobes being the
most firm. Numerous small, subpleural ecchymoses were observed scattered
over the surface of both. An attempt to inflate the lungs with a blow-pipe
oidy partially succeeded. There was no evidence of pleurisy. The heart was
normal. The abdomen was large and rounded, dull on perciission over
nearly its entire surface, and a large, solid body filling most of its cavity could
be felt through the abdominal walls. On section this body was found to be a
ponderous liver. A small area of the lower anterior surface of the right lobe
had become attached to the abdoininal walls by recent inflammation. About
six ounces of a dark straw-colored fluid containing a few whitish flocculi were
found in the abdominal cavity. The spleen was of nonnal size and firm. The
kidneys presented nothing abnormal in gr-oss appearance. No other organs were
examined. The liver and lungs were placed in a solution of chromic acid.

Liver. — After the liver was sufficiently hardened for microscopical section,
a more careful examination of its gi-oss appearance was had. It was then
observed that its gi-eat volume was largely due to the increased thickness
of the right lobe. A cup-shaped depression, three-quarters of an inch in
rliameter, was observed oA the dorsal surface of the right lobe. The
cystic duct was so dilated that it formed, with the gall-bladder, a continuous
pouch to its junction with the hepatic duct. The caliber of the hepatic and
common ducts was also much enlarged. The liver in transverse sections
exhibited nrirnerous cysts, occupying more especially the central portions of
the organ, while the periphery, to the depth of from one-quarter to one-half
an inch, was comparatively normal. These cysts varied in size from a
pin's head to that of a filbert, and so closely ai»proximated one another in
certain portions as to give to those parts a close resemblance to a coarse
sponge. The cup-shaped depression above refen-ed to proved to be i)art of
a large collapsed cyst near the surface.

Under the microscope, with a power of two hundred diameters, the liver-
tissue showed marked features of sj'philitic hepatitis. Crowds of inflamma-
tory corpuscles were found filling not only the inter-lobular connective tissue,
l)ut also, in many places, the interior of the lobules themselves, thus render-
ijig the boundary line Ijetween them indistinct. With a power of six hundred
diameters, the liver epithelium in many places seemed to be transformed into
globular or slightly angiilar ineduUary coi-puscles. Such bodies filled, also, a
number of inter-epithelial capillaries, being marked in these situations by an
arrangement in rows, and also by the absence of the brownish liver tint. In
some epithelia containing an unusually large nucleus there were observable
several concentric, circular rows of small gi'anules. Only a few capillaries
held red blood-globules. All of the inflammatory coi-puscles, more particu-
larly the concentrically granulated bodies, exhibited a peculiar luster and a
homogeneous appearance characteristic of waxy degeneration. The re-agents
— methyl aniline, picro-indigo, osmic acid, and iodine — yielded only nega-
tive results. This may have been due, however, to the effect on the tissues
of the chromic acid solution. Cy.sts, too small to be seen with the unaided
eye, were observable, and some of the larger ones contained bacteria. (See
Fig. ;V21.)

Linif/s. Specimens selected from the more diseased parts showed a very
marked augmentation of the interalveolar connective tissue. Some of the air-
cells were considerably distended by the i)re\'ious inflation ; others coi're-
sponded to the api>earance of the normal foetal lung, and were onlyrecognizn-

////•; iii:si'iir\ lonY ruAcr.

'•l\)

1>1(' liy tin- ]>n's('ii('(' of llif alvi'olai' cpitlicliiiiii. 'I'Ikisc vesicles most iill'<'clc(i
T)y tlic iiiorl)i(l process w<>re crowded with eintiryoiiiil corpuscles and detached
epitheliuiii. In the more healthy air-cells, wlii(di liad Iteeii moilerately
inflated, some of the epithelia had become completely detached, and some
remained udherent to the alveolar wall. The epithelia, in many instances,
exiiibited a coarsely {jivinular apjx'arance, and often contained two or more
nuclei, while otiiers, again, had a nearly homogeneous, waxy-like appearance
and contained several concentric, circular striations and a faintly marked
nucleus. Some alveoli held, besides detached epithelia, a finely gi-anuiated,
aUniminous exudate, in which were imbedded a varying number of inflamma-
tory corpuscles. Here and there was seen an alveolus, showing a delicate
reticulum of coagulated fiV)rine. The interstitial tissue, however, presented
the most marked and characteristic lesions; it was greatly increased in (|uan-
tity, crowding upon and compressing the alveoli, and so flUod with embryonic

•/:>K.r{i

)

\ ^

A'

W^^-''\l S'

^-f*i—

Fig. 327. — Syphilitic Hepatitis,

C, interstitial ooiiiieutive tissue, crowded with inflammatory corimscles ; A', liver epithelia.
ami P, ca]iillary blood- vt^ssels containing inflammatory corpuscles: ^, I'oiicentritally strati-
fled srlobule : B. remnant of a bile-duct. Magnified 600 diameters.

corpuscles as in many places to hide the underhing blood-vessels. (See
Fig. 328.)

The result of the examination in this case corresponds in the main, so far
as it goes, to the more extensive descriptions of these organs in s\'j)hilitic
infants, given by A. Gubler.'* The microscopical appearances were essentially
the same as those given by Cornil and Ranvier t under the head[of " Syphili-
tic Pneumonia and Syphilitic Hepatitis."

Gazette M^iticalr dc Paris, 1852. t" Pathological Hi.stologj'." Am.Tican edition. 1"*S0.

730

THE RESPIRATOKY TRACT.

The exfitiihiation of the spiitti with the microscope throws light upon a
number of morbid processes in the respiratory tract. I have previously pub-
lished some of the results of my researches concerning the examination of
sputa."

The coi^juscular elements found in the discharges of the respiratorj' passages
are the following: Flat ejiithcJia of the oral cariti/ : cohnuiiar e]>itlielifi from thf
}an/ii.r, the traeliea, the bronchi, nud hrotichioU ; these are rarely seen ciliated,
since the cilia break off easily. Flat cpithelia of the alveoli of the lituy.'i, which
sUghtly surpass in diameter those of the kidneys, and, as a rule, are found
swelled and globular. In smokers, or persons exposed to smoke, they contain
a varying amount of pigment (charcoal) granules. In addition, salivary,
mucus- and pu.^-eorpi()icles- are found. l)esides a granular detritus, entangled with
mucous threads e\'idently arising from the bursting or disintegration of the
above-named corpuscles. Leptothrix, micrococci, and bacteria are also common
occuiTences in the sputa of even simple catarrhal intlamraation. Lastly, the
remnants of animal and vegetable food are found.

Fig. 328. — Syphilitic Pxeumoxia.

/, iuterstitial tissue, crowded with inttaminatory corpuscles: F, alveolus containing de-
tached epitlielia and coajrulated fibrine ; M, alveolus filled with a granular mass holdinsr
nuclei. Magnified 600 diameters.

" The most common question of physicians is: What is the difference
between mucus and pus-corpuscles ? The mucus, as well as the salivary
corpuscles, are plastids, formerly inclosed in a shell of cement-substance, and
thus forming what we call epithelia. The transformation of the contents of
epithelia mto saliva, mucus, and pepsin, has been carefully studied by E.
Heidenhain. The transformation into mucus can be demonstrated directly
on the epithelia of mucous glands of the frog's skin, and on the columnar
epithelia of the small intestine of any freshly killed animal, from which we
remove parts of the mucous lining with curved scissors. On the epithelia of
such slices we succeed in watching the process of the formation of muctis-

- " The Aid which Medical niagno-sis Receives from Kecent Di.-icoverie:
A rchiveii of Medicine, Feb., 1879.

in Microscopy."

////•; i:i:si'ii;ai(ii{Y thact. 7;;]

glolmli's from tlic l>in|iliis.s()ii of the fpilliclia, alter we liuvc adtlcil a ilioj) of a
very dilute .solution of cln'oinii- acid or l)ifliroiMatc of jjotauli, pure water beiiif;
too violent in its aetioii. We see the eontenfs nearest to the toj» of tlie
opithelia swell and beeonie transformed into a jtale, homoj^eneous nuiss.
Here the shell of the eement-sultstanee bulges out, ami is tiiinned, until it
becomes lu'oken at the point of the greatest convexity and allows the
escape of the mucus-globule. Not infreijuently the whole mass of the con-
tents is evacuated from the interior of the distended shell of cement-
substance, whicli, being partially or totally emptied, gives the aspect of
what has been termed a " cup- or goblet-cell." This lump of bioplassoii is
now a mucus-corpuscle, aiul still endowed witli i)roperties of life. Where an
inflammatory process is established, the living matter of the epithelia is .soon
increased ; in other words, their contents V)eeome coarsely gi-anular, and, if
freed in this condition, form what we call a pus-corpuscle. The main difiFev-
ence between a mucus- and a pus-corpuscle, therefore, is that the former
looks finely, the latter coarsely granular, though ]>oth are essejitially the
same. Pus-corpuscles, on the average, are also more coarsely gi-anular than
colorless blood-corpuscles. The absolute identity of these bodies cannot i>e
maintained, and the assertion of J. Cohnheim, that all pus-corpuscles — nay, all
intlammatory elements, are merely emigrated colorless Ijlood-corpuscles, is a
great mistake. The formation of pus-corpuscles from epithelia and connec-
tive tissue can be directly observed, and no one has the authority to call pus-
corpuscles altogether emigrated colorless blood-corpuscles, though all of us
agree that these share in the formation of pus."

"We cannot tell, by watching pus-corpuscles in the sputa, from whence
they come ; perhaps black pigment-granules in the pus-corpuscles indicate
that they have arisen from a pigmented lung. Only the presence of elastic
fibers in the sputa is a sure sign of destruction of the lung, inasmuch as such
fibers are present in a large amount in the walls of the alveoli. Of what
nature the destruction is can be ascertained only if the elastic fibers be
accompanied, besides pus-corpuscles, also by shriveled-up and broken lumps,
which indicate cheesy transformation of the inflammatory product, so com-
mon in tuberculosis."

Later oV)servations have demonstrated that, in ulceration of the larynx,
the trachea, or the bronchi, elastic fibers and connective-tissue shreds may ap-
pear in the sputa, the same as in ulcerative destruction of the lung-tissue.
The determination of the nature of the nicer depends entirely upon the con-
stitution of the patient, as diagnosed from the appearance of the pus-cor-
puscles. (See page .52, Fig, •_'(),) If the pus-corpuscles exhibit the featm-es
of the series /', indicative of a poor constitution, the diagnosis " tuberculous
ulceration " is justified, regardless of the seat of the destructive process. Ob-
viously, gi-eat care must be taken to have the oral cavity of the patient thor-
oughly cleansed before the sputa can be used for microscopic examination,
since the shreds of connective tissiie found may be the detiris of animal food
carried along by the sputa.

In one case echhwcocciis of the lungs could be diagnosed from the character-
istic appearance of the echinococcus sac, emptied with the sputa.

'■^Exceptionally also the new formation of mijeloma in the lungs can be diaynoscd
by the examination of the sputa alone, as illustrated by the following ease,
which occniTed three years ago. A justice of this city, about sixty years of
age. had a tumor in his right groin, which, after repeated extirpations, always

7:52 THE h'h'SI'IIfA'rORY JRACT.

veeuiTed, and recently began to grow rapidly. The consulting surgeons made
the diagnosis " cancer,'" and foretold an approaching ulceration for which the
relatives had to be prepared. The attending physician, Dr. Schoney, soon
afterward brought some sputa of the patient to my laboratory, being struck
by their large quantity. On microscopic examination, besides pus-corpuscles,
numerous globular elements were also seen, characteristic of the so-called
vound-eell sarcoma or globo-myeloma. The diagnosis was : secondary fonna-
tion of myeloma in the lungs, due to a primary myeloma in the groin, which
latter would not ulcerate. The post-mortem examinatiou a few weeks after-
ward fully corroborated my diagnosis, though I never had seen the patient.
The lungs were crowded with white nodules of myeloma, and the tumor in the
iiToin proved to l)e an alveolar myeloma which had never come to ulceration."

XIX.

THE URINARY TRACT.

THE essential parts of Ww uriijan- tract are those portions of
the kidneys which secrete the urine, while all other nieni-
hranons tubnles and sacs connected with them — /. ^., the pelves,
the ureters, the l)ladder, and the urethra — are merely a collecting
and conducting- appai'atus. The investigations of R. Heidenhain
have corroborated the views of Bowman that, from the capillary
blood-vessels of the tuft, which caiTy arterial blood, only a
watery licpiid, destitute of salts, is exuding into the capsular
space, while the saline constituents of the urine are the excretory
product of those uriniferous tubules which are richly supplied
with capillary blood-vessels, and whose epithelia are closely con-
nected with the walls of the vessels. The inspissated blood con-
tained in these vessels reabsorbs a portion of the liquid from
the tubule and supplies the liquid in the tubules with a certain
amount of its salts. Obviously, the whole process is accom-
plished through the agency of the living epithelia, and is not to
be considered as a simple process of osmosis. The differences in
the structure of the epithelia in certain portions of the urinifer-
ous tubules, and the striking differences in the distribution of
the blood-vessels, strongly point toward a difference in the func-
tion of portions of the tubules; but no exact demonstration of
these functions, concerning the constituent elements of urine,
has as yet ))een furnished. The Greek denomination, "' dialysis,"
serves to conceal our lack of knowledge of the process concerned
in urinary excretion in about the same manner that the word
" catalysis " disguises our ignorance of the process of digestion

734 THE URINARY TRACT.

in the stomach. Many an eminent observer has contributed to
onr stock of knowk^d^e regarding the minute anatomy of the
kidneys, while the physiology of the excretion of urine is still
unexplained.

(1) Tlie KidiKj/.s. The kidney consists of a cortical and a
pyramidal portion, and in man is made up of from six to twelve
united parts, each of which has a cortical and a p\Tamidal
substance. The boundary between the two main divisions is
irregular, and in parts illy defined ; each subdivision terminates
at the concave border in the center of the organ in the so-called
papilla, which is surrounded by a membranous sac — the calyx.
The loose connective tissue, between the pyramids carries the
larger blood- and lymph-vessels and the principal nerves. The
surface of the kidney of the adult is smooth, being ensheathed
by a dense, fibrous (M)nnective-tissue capsule ; while the foetal
kidney exhibits a distinctly lobate surface, indicative of its gen-
eral construction of lobes or segments. The main constituents
of the kidney are the blood-vessels and the lu'iniferous tiibules,
which are held together by a delicate, fibrous connective tissue,
rich in elastic substance, giving the whole structure a high
degree of consistency. From the arrangement Qf the tubules the
kidne}^ is classified among the compound tubular glands.

The renal arterjj enters the organ in two main branches
(Hyrtl), each of which, by a number of bifurcations dividing
in,to smaller ramules, supplies an independent half. These ves-
sels, upon reaching the Ijoundary zone between the cortical and
pyramidal substance, deviate in an oblique direction, and produce
the so-called arterial bows or arches, the convexities of which, if
marked at all, look toward the cortical substance. Each artery
in this situation is accompanied by a vein, the veins being con-
nected l)y lateral branches, and producing a sort of a venous
plexus.

From the arches arise at short intervals straight arterial
branches, which penetrate the cortical siibstance in a straight
direction and divide at very acute angles ; these arteries produce
transverse ramules, the afferent vessels which go to form the tuft.
A successful injection of the blood-vessels of the human kidney is
(piite exceptional, while the dog's kidney, which can be had in a
perfectly fresh condition, allows a plain demonstration of the
vascular supply. As the relations in the latter are very similar
to those of human kidnej^s, they may with preference be used for
demonstration. (See Fig. 329.)

•/■///•; I in.\.n>y ///.irv.

i.i.)

Tlic MtTcrt'iit \('ss('l is cillicr ;i Itriniiiiil Itraiicli of tlir i-fiuil
.•irlcry or ;i latrral offshoot of such a In-aiich, wliidi is {^ivcn oft"
without any i-ciiuhiiMty. Not iiiffc(|uciitly tlic att'ci'cut vessel
assumes a l)ael\\var(l course,

especially near the veuiou .r — ^jrX« r-. ^7^.771"-^ ^-^■'""-

]yin<i' helweeii cortex and
pyramid, in lunnan as well
JUS in do^s' kidneys. The
ultimate terminations of
the arteries and their tufts
never reach the outermost
portion of the cortical sul)-
stance, which is supplied
with capillaries only.

The afferent artery in-
variably exhibits a distinct
middle or muscle coat, and
s])lits al)rui)tly into a num-
ber of ca})illaries, which
cimtain arterial l)h>od, and,
by bein«i' convoluted and
turned upon themselves,
produce the tuft. According
to C. Ludwig the formation
of the tuft is easily under-
stood by assuming that the
arterial bed of the afferent
vessel is abruptly widened
and at the same time split
into a numlier of very
narrow (capillary) canals,
which again unite into the
efferent vessel : bring the
surface of the opposite Fig. 329. — Coktical Substance of the
parts together, so that the Kidney of a Dog. Blood-vessels
afferent and efferent ves- Injected.
sels are in proximity, and
the tuft is complete. The
formation can be readily
demonstrated with a hand-
kerchief, the two compressed ends of which are held in the two
hands, one representing the afferent, the other the efferent vessel,

Ca, capsule ; O, outer zone, devoid of tufts : 7',
tuft; ^i, afferent vessel; £, efferent vessel; i?>
branch of renal artery ; Co, zone of convoluted
tubules; .S', zone of straiglit tubules (medullary
ray). Majrnified 100 diameters.

736

THE I'lilXAIiY TRACT.

and the wliole beint^ turned upon itself, the two hands joining,
while the middle, broad portion, spread and folded, represents
the tuft. (See Fig. 330.)

The tufls^ or glomeruli, or Malpighian corpuscles, are globular
formations of 0.02 to 0.03 mm. diameter, composed of a number
of convolutions of capillary blood-vessels, which both in the
human and in the dog's kidney are aiTanged in two main lobes ;
hence, the glomerulus is a bilobate for-
mation of capillaries. One lobule isi
always larger than the other, and the
summit of the larger lobule is directed
toward the opening of the uriniferous
tubule. Each tuft is enveloped in a
delicate connective-tissue capsule (Bow-
man, H. Miiller) in a manner similar to
that in which the pericardium surrounds
the heart. Both layers, the free or par-
ietal, as well as the reduplicated glo-
merular, are composed of connective tis-
sue rich in elastic substance, the glome-
rular portion being more deli(;ate than
the parietal; both are covered with a flat
epithelial layer. The glomerular portion
sends prolongations between the capil-
laries of the tuft, and a marked prolong-
ation, together with the covering epithe-
lium, into the groove between the two
loT)ules of the tuft (Axel Key). The epithe-
lium covering the glomerular portion of
the capsule is cuboidal in the foetus and
in children, and becomes flattened in the
adult; while the epithelium of the par-
ietal portion of the capsule is always flat and blends with the
cuboidal epithelium of the uriniferous tubule, the beginning of
which it represents. At the point where the afferent vessel enters
and the efferent leaves the tuft, the capside turns over to the
tuft, and the connective tissue at this p(nnt is more freely sup-
plied with plastids ha\'ing the appeai-ance of nuclei than else-
where. (See Fig. 331.)

The efferent vessel invariably leaves the tuft near the entrance
of the afferent vessel ; it contains arterial blood, though the mus-
cle-coat is verA- imperfect, or absent. Its diamett'r is decidedly

Fig. 330. — Diagram of
THE Tuft (C. Ludwig).

A V, afferent vessel ; T, capil-
laries comijosing the tuft ; EV,
efferent vessel ; C, capillaries
for the supply of the cortical
snbstance.

THE Ih'IXAin' TKACr.

TM

siiiallcr than that of the afferent vessel. Soon after having h*ft
tlic tnft, it divides freely into cajjillai-ies for the supply of the
eortieal as well as the pyramidal sul)stance. So extensive is this
division that the kidney-tissue proper has no other capillaries
than those derived from the efferent vessels, the pyramidal sub-
stance being. Ix'sides, sui)i)lied with capilhu'ies from a few inde-
pendent arterioles. Tlie cap-
illary meshes are circular in
tlie region of the convoluted
tubules, and elongated squares
in that of the straight tubules.
(See Fig. 829.)

The arterial arches send a
few small arterial branches
downward into the pyramidal
substance. The main supply ca-^

of this portion, however, is
capillary, and of two kinds :
First, the few elongated,
square meshes around the
straight collecting tubules;
and second, the bundles of
very wide capillaries, accom-
panying the narrow tubules.
The latter are the so-called
rasa recta of the pyramidal
substance. Some authors
claim that they are arteries
produced directly from the
arterial arches, which, how-
ever, is not correct. Others
maintain that the vasa recta
arise immediately from the
efferent vessels of the tufts nearest the pyramidal substance
(C Ludwig) ; again, others consider the vasa recta as veins
which originate from the capillaries of the cortical substance,
in a manner similar to the portal system of the liver (Husehke,
H_\Ttl, Henle). We overcome all difficulties concerning the origin
of the vasa recta by considering them as considerably widened
capillary blood-vessels, which are prolongations of the narrow
capillaries of the cortical substance — a fact which is easily dem-
onstrated in the injected kidnev of the dog. (See Fig. 332.)
47 '

CT

Fig. Sfil.— Tuft from the Kidney of
A Dog. Injected.

T, capillar}' looiis of tlie tuft, in connection
with the afferent artery, coveied hr E, flat epi-
thelia: Ca, capsule, covered with flat epithelia.
in coinmunicatiou witli Co, the coiivoliitetl tu-
bule; CL, convoluted tubule in longitudinal sec-
tion: CT, convoluted tubule in transverse sec-
tion. Ma^'nitied 350 diameters.

738

THE URINARY TRACT.

The ascending branches of the arterial arches which give rise
to the afferent vessels are, by most authors, termed inter-lobular
arteries. This name should l>e abandoned, for the reason that
they occupy the center of a cortical lobule (Lud wig's labyrinth).
The capillaries of the cortical substance are usually considered
to be of two kinds — those rising directly from the efferent ves-
sels, for th(^ supply of the

medullary rays, and those of
the labjT^nth, which are pro-
longations of the former.
This conception is, however,
misleading, inasmuch as the
efferent vessels produce the
capillaries of the labyrinth
and the medullary rays, both
directly and indirectly, and
there is no necessity for
speaking of arterial and
venous capillaries. Fig. 329
shows the distribution of
the capillaries from the ef-
ferent vessels, sfmie running
first to the lab\Tinth, others
first to the medullary rays.

The veins arise from the
capillaries of the cortical
substance, especially those
of the labyrinth, and their
confluence is often marked
on the surface of the kid-
ney in the form of stars
(stellulae Verheyenii). As
the medullary rays are lost
near the surface of the kid-
ney, and the outermost por-
tion of the cortex has no
tufts. ob\'iously the veins
arise from the e^ipillary sys-
tem surromiding the con-
voluted tubules. The veins accompany the arteries, and empty
into the venous plexus at the boundary zone between the cortex
and the pyramis. The latter furnishes veins derived both from

Fig. 332. — Boundary Zoxe betwkex
THE Cortical and Pyramidal Sub-
stance OF THE Kidney of a Dog.
Blood-vessels Injected.

A, bi-aDcli of renal arter>-; Co, i)rolongatioii of
the cortical substance; T, tuft; .S'. bnnille of
straiglit tubules ; O, origin of the vasa recta from
the cainllaries of the cortical substance ; B, bun-
dle of vasa recta. Mafpiified 100 diameters.

Tl!K VlilXAliY TRACT. 739

the capillaries of the eollectinfi: tul)ules and from the vasa recta,
the aset'iulinj:; loops of which empty dii-cctly into the inter-zonal
venous plexns.

Aceordiny; to C Ludwii^:, the capillaries of the capsnle and of
the surrounding; fat-tissue of the kidney, which arise partly from
small hranchesof the renal arteiy Ix'fore it reaches tln' hounding
zone, are united directly to the capillaries of the kidney-tissue.

The uriniferoHs tuhules originate from the capsules of the
tufts, op})osite the site of the blood-vessels, as first discovered by
Bowman, and terminate, after uniting and })eing considerably
reduced in numbers, at the papilla of the pyramid. They are
chiefly of two kinds: convoluted and sfraif/hf. The former con-
sist of convoluted tul)es of the tirst and second order; the latter
are the straight, narrow and straight, collecting tubules. The
con vol i( ted tnhulea of the first order occupy the portion around
the ascending branches of the renal artery, and their sum total
is termed the "labyrinth" by C. Ludwig; the convoluted tubules
of the second order fill the most external portion of the cortex,
in which there are no tufts. The strciif/ht tubules, both narrow
and collecting, produce the medullary rays between the laby-
rinths in the cortex ; while in the pyramids they run in separate
bundles according to the f ollowdng arrangement : First, the nar-
row tubules, together with the vasa recta, in the imaginary pro-
longations of the lal)yrinth, and then the collecting tubules as
direct prolongations of the medullary rays of the cortex. Fig.
333 represents the generally adopted schema of the course of the
uriniferous tubules, first issued by Ludwig and Schweigger-
Seidel. The results were obtained both by isolation of the urin-
iferous tubules, by means of maceration in dilute acids, and by
the study of kidneys in which the blood-vessels and uriniferous
tubules had been injected with colored gelatine. In this depart-
ment C. Ludwig was most successful. (See Fig. 333.)

The details are as follows : The convoluted tubule (of the first
order) originates from the capsule of the tuft as a slightly nar-
rowed, funnel-shaped neck, and, after repeated convolutions
within the labyrinth, tends toward the medullary ray. Here it
becomes (to varying depths) narrow, often exhibiting spii'al
windings (Schachowa) before decreasing in caliber, and repre-
sents the descending branch of the loop, or Henle's tubule. This
enters the pyramidal substance, producing a distinct, angular
divergence at the dividing zone between cortex and pyramid, in
order to reach the bundles of the vasa recta. After reaching

740

THE URINARY TRACT.

Fig. 833. — Diagram op the Kidney.

A, renal artery; V, reual vein; 1\ tuft; CT. caiisuU" of tuft; AV, afferent vessel; EV,
efferent vessel ; CC, cai)illaries of convoluted tubules; C.S', caiiillaries of straight tubules; £,
arterial branch to tlie cortical .substance; ^P, arterial branch to the pyramidal substance ;
VH, vasa recta; CP, capillaries of the straight collecting tubules; L, cajiiUaries of the
papilla; C/, convoluted tubule of the first order; A", narrow or loop-tubule ; C'if, convoluted
tubule of the second order; .S', straight collecting tubule in the medullary ray of the corti-
cal substance ; C, straight collecting tubule in the iiyraniidal substance ; P, the same at the
papilla.

TIIH ClffXAh'Y TKM'T. 741

certain <l('i)tlis in the ](\ rainidal sn})stan(!e, the narrow tnbulf
prodnccs a /ooy> (the looj) of Ilenk"), and takes an npward eonrse
as tlie ((srctuJiiH/ hninrh of the narrow tubule, tliis iM'iiif); on the
whole sliii'litly wider than the deseendinj;' portion. A<;ain, the
aseendin^' branch widens, with short, irreg'ular curves and angles
(the irregular portion), and at the most peripheral part of the
cortex, in wliicli there exist no tufts, it resunu's the; width and
aspect of the convoluted tubule, l)eing' in this situation termed
the coHvolnted ftihuh' of the second order, or the intercalated
tubule, which inosculates with the straight collecting tubuh\
By the union of several intercalated and collecting tubules arches
are fornu'd. Henle insists upon the arched arrangement of the
collecting tubiiles themselves, to which the intercalated tubules
are joined. The colIecfi)ig tuhnle occupies the center of the medul-
lary ray in the cortex. The groups of collecting tubes in the
pyramis are situated between groups of the narrow tubules,
decreasing in number, by continuous union at acute angles of
analogous formations, until, lastly, a limited number of wide col-
lecting tul)ules (eight to fifteen) open at the point of the pyramis
— the papilla — which protrudes into the calyx. Their mouths are
visible to the naked eye, and are called the foramina papillaria —
the "blessed sieve" (cribrum benedictum) of old anatomists.

The uriniferous tubule may iu its course, though not eonstaiitly, exhibit
slight variations in its caliber and structure, and thus a number of subdivi-
sions of their portions may be admissible. E. Klein, for instance, gives the fol-
lowing complex diagram of the course of a uriniferous tubule : (1) capsule of
the Malpighian corpuscle ; (2) naiTowed neck ; (3) the proximal convoluted
tubule; (4) the spiral tubule of Schachowa, which is already part of the
medullary ray; (5) the descending branch of Henle's loop; (G) the loop
itself, which, turning upward and reaching the boundary layer, becomes
suddenly enlarged and slightly wavy, thus forming (7) the fii'st thick portion
of the ascending limb of Henle's loop, and (8) the spiral part of the ascend-
ing limb; (9) then it becomes narrow again, and more or less straight or
slightly curving; (10) produces the irregular tubule, with angular convolu-
tions; (11) the intercalated segment ; (12) the ciuwed part of the collecting
tube ; (13) the straight part of the collecting tube of the cortex in the medul-
lary ray ; (1-t) the collecting tube enters the boundary layer, and lastly, the
papillary portion ; by continence becomes ( 1."}) the large collecting tube, or
tube of Bellini, imtil (16) it opens as one of the duets on the free surface of
the papilla.

Each portion of the uriniferous tubule has its peculiar epithe-
lial lining. This, in general, can be defined as being cuhoidal in
the convoluted tubules, Jfat in the narrow tubules, and columnar
in the collecting tubules.

742 THE URINARY TRACT.

The convoluted tuhules of the first order, having an average
diameter of 0.0045 mm., are lined by polyhedral epithelia, the
cement-substance between them often being illy defined, or, espe-
cially in kidneys of children, absent. In these epithelia R. Heiden-
hain discovered a rod-like structure similar to that o})served in the
epithelia of the ducts of salivary glands. The ascending and de-
scending portions of the Hdrroiv tiihides have a diameter of 0.0020
to 0.0025 mm., and are lined by cuboidal epithelia, which also
exhibit the rod-like structure ; this peculiarity is particularly well
marked in the irregular portions of the tubules. The descending
portion gradually becomes narrow, and its epithelium passes by
degrees into the flat variety, while the ascending portion often ap-
pears abruptly widened close above the loop, or in the depth of the
loop itself. Along the course of the ascending tubule within the
cortical substance the epithelium again may become flat, corre-
sponding to a narrowing of the caliber. The narrow portions
have a diameter of 0.0014 ; their caliber is comparatively wide,
and the flat epithelia are finely granular and supplied with a dis-
tinct nucleus. In edge-view these epithelia appear spindle-
shaped, closely resembling the endothelia of capillaries. The
convoluted tubules of the second order have only a few convolu-
tions ; their caliber is somewhat wider than that of the convo-
luted tubules of the first order ; their epithelia, however, being
identical with those of the latter. In the irregularly winding
portions the epithelia show slight differences in their depths.
The collecting tubules have the widest caliber, their diameter
being, at the apex of the medullary ray, the same as that of the
convoluted tubules, while in their course toward the papilla they
gradually assume a diameter of 0.020 to 0.030 mm. Their epi-
thelia are at first cuboidal, but with increasing caliber the epi-
thelia become distinctly columnar, being finely granular and
obliquely arranged in the lower portions, after the manner of
shingles on a roof. According to C. Ludwig, the membrana
propria near the papillae is fused with the surrounding connect-
ive tissue.

All tubular formations of the kidney are ensheathed by deli-
cate connective tissue, which carries the blood-vessels and nerves.
The peculiarities above described may be shown by antero-poste-
rior (sagittal) sections of the kidney, which sever the tubules in a
transverse direction. (See Fig. 334.)

Sagittal sections of the cortical substance will exhibit, within
the medullary ray, transverse sections of the narrow tubules,

Tin-: riusAUY ihact.

743

1 .) ^\ ]■

>1^

;V^

t'liicfly tilt' ascciKliii}^- lirimclifs. ;iii<l of the collcctin}^ fulmlcs, iill
of wliicli arc fcwci" in umiiJx'i" and of a less marked cliaractcr tin;
noarer the surface of the kidney, the main l»ulk of whieh is occu-
])ied l)v convohited tnlmles. Sauittal sections of tlie ])vraniidal
snbstance arccharacterizt'd l»y bundles of tlie vasa recta arranged
to«;ether with transverse sec-
tions of the narrow tubules,
both the ascentlinjj, descending,
and h)o])ed ])()rtion, around ( .
which are g'rouped the trans- ^

verse sections of the collecting \
tubules. The narrow tubules
become fewer, and the collect-
ing tubules wider the nearer
they approach the papilla.
(See Fig-. 835.)

Of the h/ni/)lKifirs of the kid
ney very little is known. Some
authors claim that they are
clefts in the interstitial con
nective tissue, while others de- Fig. 334.— Cortical Substance op
scribe rhomboidal meshes of the Kidney op a Dog. Sagittal

1 1 ,• 1 111 Section. Blood-vessels Injected.

lymphatics, bounded by an en-

1 ii T 1 i. Til • C, convoluted tubule : N, narrow or loop-

dothehal coat, around the Unn- t^,^„,^. ^^^ ascenmng branch of narrow tu-

if erOUS tubules. In the capsule l^'l*^ - *'• straight collecting tubule. Magnified
„ , , - . T , , . , 500 diameters.

ot the kidney there is a regular

lymphatic system, and in the hilus several large lymph-vessels

are found which are supplied with valves.

The nerves of the kidney have been, for a number of months,
studied in my laboratory by Dr. M. Holbrook, who has not yet
completed his researches. He found a large number of nerves
accompanjdng the arteries and producing a reticulum around
the capillaries, in accordance with the statements of L. Beale.
Every tubule is accompanied by a reticulum of non-medullated
nerve-fibers, from wliich prolongations pass through the base-
ment-membrane, and produce a very narrow plexus close above
this membrane. From the intra-tubular plexus delicate branches
arise, running along the cement-substance of the epithelia, and
in union with the slender, transverse filaments traversing the
cement-substance and inter-connecting the epithelia. Such fibril-
lae are represented in Fig. 337. By Holbrook's specimens it is
plainly shown that every epithelium is in connection \\'itli a

744 THE UBINABY TBACT.

nerve-fil)ei', thougli this connection is indirect throug-h the inter-
epithelial filaments of living matter (the so-called thorns). It
conld not be demonstrated that the nerve-fibrillae penetrate the
interior of the epithelia.

Researches in the Minute Anatomy of the Epithelia of the
Kidney. By Henry B. Millard, A. M., M. D.*

K. Heideuhain t was the first to call attention to the presence of a peculiar
rod-like or bacillated structure existing in the uriniferous tubules. He found
this structure in convoluted tubules, in the ascending portions of the looped

•-■\' D

m

iS'

lkp^\t

Fig. 335. — Pyramidal Substance of the Kidney of a Dog.
Sagittal Section. Blood-vessels Injected.

iV, narrow or loop-tubule ; XU, tlesceutling braucli of narrow tubule ; .s', straight collfctin-r
tubule; F, vasa recta. Miignified 500 diameters.

tubules, and in the intercalated tubules of the kidneys of mammals. Accord-
ing to his view, the rodlets (Stabchen) are plainly visible in the outer portions
of the epithelia — that is, in those portions lying next the connective tissue,
and he sometimes saw in torn epithelia the rods isolated. The same observer t
also first demonstrated with accuracy that the secretion of the salts is per-
formed only in the tubides, in accordance with the views maintained by Bow-
man. Charcot^ deduces from the experiments of Heidenhain witli indigo-blue

* Abstract of the author's essay. The Keiu York Medical Journal, June, 1882.

t "Mikro.sk. Beitriige zur Anat. unil Phy.siologie der Nieren." Max Schultze's "Arch. f.
niikr. Anat.," 10 Bd., 1874.

X " Versuche iiber den Vorgaug der Harnabsonderung." I'lliiger's " Archiv," 9 Bd., 1874,
l)age 1.

^ "Charcot on Bright's disease," translated b3' Millard, New- York, 1878, page 23.

TllK L'JUXARY TliACT. 745

till' fKiu'lusion that the secretion or eliiniiuition of tliis coloring mutter takes
pliiee only in those portions of the tnbnli uriniferi wliidi are covered l)v the
epithelia havinjj the roils (epith^'linin i\ hatonnets). Whether the secretion
of the sjx'eifii' princijiles of the urine takes jjhice in precisely the same fashion
as the elimination of coloring matters, he regards as impossil)le of demonstra-
tion experinu-ntally. In a recent monograph, Charcot * regards the Inhuli
coiilorii and the loops of Henle, ]iarticnhirly the ascending branches of the
loops, as the real glandular part of the kidney. Heidenhain, however, did
not associate the rods with the jn-ocess of secretion, for he observed a similar
structure also in the smaller ducts of the ])arotid and suljmaxillary glands,
the same fornuition in the latter structure being already known to Henle
and Pfliiger. In the acini of the glandula submaxilhiris and in the other
acinous glands he could not discern them. E. Klein t asserts having ob-
served that the rods or fibrils of Heidenhain, when looked at from the sur-
face, are connected into a net-work, so that they are more probably septa
of a honeycombed net-work seen in profile. What the intimate nature
of these formations is, neither of the above-named authoi's attempts to
explain.

Since the reticular structure of all protoplasmic formations, including
therefore epithelium, was demonstrated l)y C. Heitzmann, the question has
been, what the reticulum present in the protoplasm is. A proof of the reticu-
lum being the living matter proper rests upon the fact that, both in normal
and in morbid processes, the new formation of corpuscular elements starts
from the points of intersection in the reticulum. This so-called endogenous
new formation of living matter is especially plain in the inflammatory process
invading epithelial formations. Here, it is important to note, the reticulum
at first becomes coarse ; next, it coalesces into lumps, which, being at first
homogeneous, in turn assume a reticular structure themselves, and now rep-
resent so-called inflammatory or pus-corijuscles. These corpuscles at first
remain in connection with the neighboring reticulum by means of delicate
filaments, which are portion and part of the reticulum. Later, when the in-
flammatory corpuscles which have originated in the interior of an epithelium
become extruded from its interior, the newly foi-med corpuscles represent
pus-corpuscles.

In conducting my researches, I have studied the kidneys of the rabbit,
pig, dog, and man, all of them being preserved and hardened in a solution of
chi'omic acid. I have, therefore, no observations to report upon the form-
changes of the epithelia, but have studied the changes in the interior striicture
of the epithelia iu the inflamed human kidney. These investigations enable
me to maintain that the reticular structure of the epithelimn of the kicbiey is
realJij a Jhnitatioti ofJirhuj nidtfer.

Upon closely examining the epithelia of the tubuli uriniferi in the kidneys
of the above-named animals, we readily perceive, with comparatively low
powers of the microscope (400 or .500 is sufficient), the presence of rod-like
formations in the epithelia of the txbiili rouford, in the irregular tubules, in
the ascending branch of the looped tubules, and in the intercalated tubules,
entirely in accordance with Heidenhain's assertions. The dra^\'ings of the
rodlets, as given by Heidenhain and copied by Klein and other wi-iters, give
an exaggerated idea of the real appearance of the rods. Even imder a high

" Lecoiis sur les Conditious Patlioirt-uiques do rAlbuininuric," Paris, 1881.
t " Atlas of Histolofry," Lomlun, 1880.

746

THE I'RIXARY TBACT.

r^-^'A-^J

power they are never so large as in the drawings, and seldom present the
straight, regular, and symmetrical appearance there represented.

The pale, flat epithelia of the looped tubule proper do not, asarule, exhibit
the rods. The columnar epithelia of the collecting tubules, on the contrary,
which are distinctly imbricated, especially in the kidney of the dog, exhibit
the rods more or less plainly. The columnar epithelium of the rabbit does,
however, show them.

High powers (1000 to 1200) of the microscope corroborated the views
of Klein — namely, that the rods are connected into a reticulum by means of
delicate filaments inosculating both with the wall of the nucleus around which

the rods are located, and also with the
delicate reticulum in the inner portion of
the epithelia, next to the caliber, where
the rods are usually absent. It is striking
how the thickness of the rods differs in
the different epithelia of the same ani-
mal's kidney. Sometimes they are very
thin, beaded poles, with quite distinctly
marked interstices between them. In
this case the connecting filaments, run-
ning almost at right angles from rod to
rod, are easily discernible. At other
times the rods are rather bulky forma-
tions, ha\'ing but extremely narrow in-
terstices between them. In this instance
the connecting filaments, as a matter of
course, are very short, and not easily
seen. In a third instance the outermost
portion of the epithelium is a compact
or homogeneous mass, in which no rods
can be obser^-ed at all. (See Fig. 3.36.)

Another striking feature is the great
variety of appearances exhibited by the
cement -substance. Sometimes this is
plainly marked at regular intervals be-
tween the epithelia. Then the transverse
connecting filaments, the formerly so-
called thorns, are plainly visible. At
other times hardly any trace of cement-
substance is seen, but the reticular struct-
ure is present in a nearly uniform distribution throughout the epithelial
layer. Where the rods are slender, the nucleus, as a rule, is well defined ;
where, on the contrarj-, they are bulky, the nucleus is, on an average, not
very plainly marked. The sharpest definition of the nucleus is furnished by
the flat epithelia of the looped tubules in which the rods are absent.

In inflamed kidneys of man I have repeatedly found the rods. Here the
rods of the epithelia throughout the tubules are clumsy and bulky, the whole
reticulum being enlarged, rendering the epithelium, with low powers of the
microscope, coarsely granular. In many instances the rods are not discernible,
as, in their place, a coarsely granular mass is present, pervading the whole
epithelial body ; or else the innermost portion of the epithelium looks coarsely

Fig. 336. — Coxvoluted Tubule
FROM THE Kidney of a Rab-
bit. Longitudinal Section.

.V, nucleated columnar epithelium,
showing the rods : E, endothelia ; I, in-
terstitial connective tissue, producing
the basement-layer. Magnified 1200 di-
ameters.

THE riilSAUY Th'ACr. 747

granular, the outermost i)orti()n, on tlu' coutriiry, being homogeneoiiH and
shining. I have repeatedly seen, in acute interstitial nej>hritis, even the looped
tubules, whieh in this situation were considerably increased in bulk, provided
with a coarsely gi-anular reticulum — nay, even with an indistinct, rod-like
structure. All these features become still more prominent by staining the
specimens with the chloride of gold after they have been soaked and washed
for several days in distilled water. This reagent, in a half per cent, solution
brought ill contact with the specimens for forty minutes, renders sections
from the normal kidney of a brown-violet hue, slightly increasing the distinct-
ness of the reticular structure of the epithelia. In the inflamed kidneys of
man, the epithelia of a gi'eat many of the ascending, irregular, and convo-
luted tubules, upon being stained with the chloride of gold, as above described,
became dark violet. With higlier powers of the microscope we can ascertain
that it is the coarse reticulum, the bulky rods, and the homogeneous masses
sprung from coalescence, as it were, of the rods, which exhibit the deepest
gold stain.

As it is the tubuli uriniferi which have the rod-like structure, which in
Heidenhain's experiments with indigo sulphate are the only ones which
are colored by it, so in the inflamed kidney it is only these tubules that
become colored by the gold. It seems reasonable to suppose, fi-om the
effect of these reagents, that the epithelia with rods, perhaps by virtue of
their ha\"ing more living matter and a more bulky reticulum, are of most
importance in secreting oy forming the extractive matter of the urine.

In the inflamed kidneys, in which the violet coloration was produced, no
doubt the reticulum of the epithelia, owing to the inflammatory process, was
considerably increased in bulk. The most marked \T.olet stain was exhibited
by a number of the convoluted tubes and by irregular and ascending tubules.
We know that living matter is considerably increased in amount in the inflam-
matory process, and are justified, consequently, in maintaining that the
reticulum and the rod-like formations within the epithelium, being part of the
reticulum, are formations of living matter. (See Fig. 337.)

As to the significance of the rods, it maybe inferred that they are in close
relation with the process of secretion. Obviously, the stream of liquid nm-
ning from the neighboring blood-vessels through the epithelia toward the
liquids contained in the caliber, and rice versa, will be facilitated by an elon-
gated arrangement of the reticulum — /. e., the rods. In a state of compara-
tive rest the rods lie close to each other — nay. are coalesced into homogeneous
masses. In this condition the cement-substance between the epithelia is best
marked. In full acti\ity of the epithelium, on the contrary, the rods will be
very distinct, will stand farther apart, and the cement-substance between the
epithelia will, in consequence, become indistinct.

The Etidothelia of the Urinary Tiihides. While investigating the peculiarities
in the structure of epithelia of tubuli irriniferi in their normal condition, I
often observed the presence of flat, spindle-shaped bodies between the basis
of the epithelia and the adjacent so-called structureless membrane of the
tubule. These spindle-shaped bodies doubtless correspond to those flat,
nucleated formations which cover the inner surface of the structureless layer
in nearly all epithelial — /. e., glandular — formations. By most observers
they are regarded as endothelia belonging to the connective tissue subjacent
to the epithelial layers. V. Czerny was the first one to bring them to ^•iew in
other tissues, which he did by staining the specimens with the nitrate of

748

THE UBINABY TBACT.

silver; and C Ludwig," also by tlu; silver stain, first indicated their presence
in the urinary tubules.

Such an endothelial layer, present in all varieties of the urinary tubules,
is best visible in the front view of the structureless membrane, where the
epithelium is stripped off. Here the endothelia are comparatively large, irreg-
ularly polyhedral bodies, with distinct central nuclei. The nucleus has a

plainly marked shell, containing in
its interior a few small nucleoli, the
nuclei being mostly of oblong shape.
In the body of the endothelium a
delicate reticulum is seen with very
minute nodulations. Each body is
separated from all its neighbors by
a delicate light rim of cement-sub-
stance, which is traversed at right
angles by extremely minute fila-
ments or thorns. In side view, ob-
viously, these bodies will exhibit a
spindle-shape, the broadest portion
of the spindle corresponding to the
central nucleus.

If the views of recent observers
are correct — namely, that the struct-
iireless layer, synonymous with the
hyaline or basement-layer, is an ag-
gregation of endothelia infiltrated
with elastic siibstanee — this view
may also be applied to the struct-
ureless membrane of the urinary
tubules. In normal kidneys I failed
to discover nuclei in the structure-
less layer proper, which would indi-
cate their construction of former
endothelia. In infiamed kidneys,
on the contrary, no doiibt was left
as to the fact that the structureless
layer is composed by a number of
closely attached, in part nucleated,
endothelia.
In the inflamed kidney the endothelial layer beneath the epithelial is
always more marked than in the normal kidney. In chronic catarrhal (in-
terstitial or desquamative) nephritis, all the tubules that have lost their
epithelial investment invariably show an investment of endothelia.

This, in the transverse section of the tubule, is characterized by the pres-
ence of flat, irregularly spindle-shaped bodies, which are always more coarsely
granular than in the physiological condition. Their nuclei are also more
coarsely granular, sometimes homogeneous. The flat shape, the large size in
the frontal diameter, and the construction of the nuclei serve for an accurate
contradistinction to epithelia. I have failed in obtaining specimens indicative

Fig. 337. — Convoluted Tubule
FROM A Human Kidney Affected
WITH Acute Catarrhal (Inter-
stitial) Nephritis. Oblique Sec-
tion.

P, Inflanniiatory corpuscle, siirnug from the
tUvision of an epithelium ; P, cluster of iuflam-
matory corpii.scli's, s]iruug in the same man-
ner ; if, rods of cuboidal epithelia, still recog-
nizable; E. endothelia, increased in size and
nnmber. Magnified 1200 diameters.

' Hand-book of Histology," by S. Strieker, London, 1874.

TllK riilXAHY TRACT.

749

of a new fonnution of oititlu'lia after tlic loss of tlic orij^iiial ('|)itliclial iiivcHt-
ment. (See Fij;. liltS.)

It may bo admissible to assume that tlie eiilar^cd emlotlielial layer servers
(at least to some extent) as a substitute for the lost epithelia. In tubule*
whose epithelia, as in ehroiiie eatarrhal nepliritis, are transformed into inflam-
matory or nu'duUary eorpuscles, tlio new formation of sucdi structures also
starts from the endothelia. The
final result in this instance is
known to be the destruction of the
tubule and its replacement l)y
newly formed connective tissue —
a condition which is known })y
pathologists as cirrliosis of tlie kid-
ney.

8till more plainly marked are
the endothelia in croupous (pareu-
chymatous) nephritis. In fact, the
appearances seen in urinary tu-
bules, where easts have just form-
ed, could not be explained, unless
l)y the presence of endothelia. We
do not yet know what the mass
composing a cast really is. This
much, however, is certain, that
easts are proteinates and forma-
tions of an albuminous or fibrinous
exudate from the blood-vessels.
This exudate, before it reaches the
central caliber of the tubule, nec-
essarily must saturate the iutei'-
vening epithelia, whose structiu'e
is completely destroyed by this
process.

It is not my purpose to dwell
upon the origin of casts ; but, from
what I have seen, I cannot concur
with Oedmansson * in the opinion
that every cast should be regarded as a product of secretion furnished by the
epithelium. I am sure that the epithelia perish in the formation of the cast.
Neither can I agi-ee A^ith Charcot t in the opinion that some (gi-anular) casts
are made up of broken-down epithelial cells, others (hyaline and some gran-
ular) of an albimiinous substance, while epithelial casts are agglomei'ations
of epithelial cells more or less altered. Bartels \ insists that, in every case in
which he has examiued microscopically thin sections of diseased kidneys
whose tubules were blocked by the dark granular casts, the tubules invariably
exhibited an epithelial lining, reconciling this fact with his view by admitting
that the theory of Key and Bayer — that the epithelium thus shed is rapidly
reproduced — may be correct. From my observations it is ob\-ious that the

* Bartels, vou Zieiiissen's "Cj-clopiudia," vol. xv., pp. 84.

t Charcot, " Briglifs Di.sease." Millaril'-s translation, New-York, 1878, pages 29 et seq.

t Bartels, op. cit., pp. 84-86.

Fig. 338. — Convoluted Tubule from
A Human Kidney Affected with
Chronic Catarrhal (Desquama-
tive) Nephritis. Oblique Section.

' ', caliber, wideuert bj- loss of the epithelia :
JS, euclothelia, increased in size and number : F,
interstitial Hbroiis connective tis.siie, with aug-
mented plastids. Magnified 1200 diameters.

750

THE UBINARY TRACT.

last three writers have regarded the eudothelia, as I have described them,
as epithelia.

Whenever we find a cast within a tubule, especially in transverse sections
of the tubule, we almost invariably see a wreath of irregularly spindle-shaped,
partly nucleated bodies, which I am sure are nothing but the lining endothelia
of the structureless membrane. Alfred Meyer * gives illustrations of these

wreaths, which evidently are drawn
with the greatest accuracy; but he
does not realize at all their character
or significance, for he suggests that
they are constructed either of rem-
nants of the former epithelia, of
which a large portion has been de-
stroyed in the formation of the cast,
or that they may be newly formed
epithelia. In both these views he
is mistaken. The epithelia are cer-
tainly gone, entering, in a consider-
ably swollen condition, the mass of
the cast, and what is behind the cast
is not newly formed epithelia, but
E merely the endothelial investment
of the structureless layer, consider-
ably increased in size. (See Fig.
.•339.)

Not infrequently we see widened
lu'inary tubules — as a rule, of the
convoluted variety — entirely desti-
tute of epithelia ; or we see such tu-
bules containing a cast broader in
its diameter than the caliber of the
tubule would be if the epithelial
layer were present. The latter feat-
ure is explicable by the fact that
casts may be carried into tubules far
distant from the place of their ori-
gin— into tubules, besides, which
have been previously deprived of
their epithelia. There is no cogent necessity whatever for the conclusion that
casts may form in tubules after these have lost their epithelia. In neither of
these instances shall we ever miss the endothelial investment, although this is
often found in a mutilated or imperfectly developed condition.

The results of my researches may be summed up in the following state-
ments :

1. The rods discovered by Hcldenliain in some varieties of the tubidi uriniferi
are part and parcel of a, reticulum present within everi/ epithelium.

2. The reticulum, including its elongated, rod-like formations, is the Uviiig mut-
ter proper.

Fig. 339. — Convoluted Tubule prom
A Human Kidney Affected with
Acute Croupous Nephritis. Ob-
lique Section.

C, hyaline cast ; B, swollen and disinte-
grated epithelia paiticipating- in tlie formation
of tlie cast; E, wreatli of endothelia: /.inter-
stitial connective tissue. Magnified 1200 diam-
eters.

■ " Untersnchungen iiber acute Niereuentziiudunf
zuWien," 1877.

'Sitziingsb. d. Akad. d. Wissensch.

THE J'UISAHY TRACT. 751

3. Thr relation of the rods to the rrst of the rcticiilinii of an epitlirlial hixhj
varies f/rratli/, the rariation iirobahltj hein;/ <hie to (lifl'erent ,stai/es or (le(/ree.s of
secretion.

4. 'I'lir retieulniii. iiielioliii;/ the rod-lihe foniialions, in the iiijlannnfitori/ jiroe-
<'.s',s', ftoth in catarrhal and cronpous ncjdiritix, (fires rise to a new formation of lir-
intj matter, which resnits in the new formation of medidlarif cor/tnscles or
jn<.'<-coriiiisvles.

f). The strnctnreless memlirane is lined In/ flat eiidoflielia It/iiu/ lietween it and
the Ixtsis of the epithelia of the urinary tubnies.

(). In nephritis the cndothelia become considerablj/ e)dart/ed, and in catarrhal,
as well as in cronjmus nephritis, they line the urinary tubnies after the epithelia
hare been shed or lost ; they surround the east in croupous nephritis after the ejii-
thelia hare perished in the formation of the east.

Nephritis. Under the head of Brif/hfs disease are included a
number of morbid processes of the kidneys which comprise
mainly acute and chronic inflammation and its terminations.
No clear understanding of nephritis was hitherto possible on
account of the lack of discrimination between its different
forms and degrees, although this disease is far more common
than is usually thought, as proved ])y the careful examination
of the urine of even apparently healthy persons. Every acute or
chronic disease of the organism, terminating fatally, reflects upon
the kidneys to such an extent that, with the exception of sudden
and accidental deaths, normal kidneys are never found on autopsy.
In three hundred post-mortem examinations of persons dead of
tuberculosis in its manifold appearances, I have never met with
perfectly healthy kidneys ; and in most the cases of persons dead
of different acute or chronic diseases, the kidneys were also found
in a pathological condition — at least, so far as the examination
with the naked eye admitted of conclusions.

Instead of the more modern terms interstitial, desquamative,
parenchymatous nephritis, and the insignificant term Bright's
disease, involving all varieties of nephritis, I prefer to adopt the
old-fashioned terminology of humoral pathology. As explained
in previous chapters, every inflammation of glandular organs is
interstitial, desquamative, and parenchymatous, as the process
starts in the vascularized connective tissue and the epithelia
participate, as it were, in a secondary way. I distinguish differ-
ent degrees of nephritis, which are : the catarrhal, the croupous^
and the suppurative, each of which may be acute, or chronic, or
subacute — i. e., chronic with repeated acute recurrences.

The two following articles are the results of careful researches
made on a large number of kidneys both of human beings and of
animals. They throw light upon the hitherto dark subject of

752 THE UlUXABY TBACT.

nephritis, especially so the article on ehronic nephritis. Avhieh is
based on researches extending over years. The secondary changes
of the kidney-tissue, embracing the formation of cysts, the fatty
and waxy degeueratif)n. are cleared up in a satisfactory manner.

Here I briefly wish to allude to the peculiar formations, termed
tubular casts, which are obsen-ed under the microscope in the
urine as well as in the tubules of the kidneys. They were first
described as occurring in both situations by Henle in 1842, who
considered them to be coagulated fibrine. Since that time the
views concerning their origin have greatly changed ; they were
considered as products of secretion of the epitheUa of the
tubides, or as transformed epithelia. l)ut the particix)ation of the
blood in the formation of casts was neglected. X. A. J. Voor-
hoeve.* in an excellent article, gives the results of experiments
made for the purpose of tracing the origin of the casts in the
tubules. This author produced casts in ral)bits' kidneys by
administration of cautharides and of neutral chromate of am-
monia, and by ligation of the lu-eters. and especially by a tempo-
rarily impeded circulation in the kidneys through compression
of the renal artery and the renal veins. He conies to the conclu-
sion that only the dark granular casts are due to a disintegi-ation
of the tubulai' epithelia, while hyaline casts are caused by dis-
tiu^bances in the vascular system, without the least participation
on the part of the epithelia. He claims having observed within
the tubule the epithelial wi-eath around each cast. Ximierous
observations in inflamed kidneys led me to the conchision that
the wreath of partly nucleated flat bodies around the casts are
not epithelia. but the grown-up eudothelia, subjacent to the epi-
thelial cover, while the epithelia, being saturated with an exudate
from the neighboring blood-vessels, are transformed into the mass
composing the cast. How this conception has developed is shown
by the foregoing and the two following articles. A simple
hyperaemia of the kidneys cannot, as is generally believed, lead
to the formation of the casts, as they are always the products
of an inflammatory action, which is also well marked in the
surrounding connective tissue. Voorhoeve's experiments eluci-
date the probable source of nephritis in pregnancy, which in
all e\-idence is caused by a pressure on the renal vein of the
pregnant uterus, mostly in the right kidney.

Nephritis, as every other disease, is mai'ked by various degi*ees

* " Ueber des Entstehen der sogenannten Fibrincy Under."' Yirchow's
Ai-chiv, LXXX. Bd., IS 80.

TUK Ih'LWih'Y rUM'T. 753

of int«'iisity. Soinctinics it aj)])('ars in a mild form, not seriously
interfering; with the <>;eneral health of the jterson, while in other in-
stanees it destroys life in a very short time. The i)resenee of easts
in the nrine I consider a serious symj)tom, thou»jh, if present only
in small numbers, they indicate a slight intianimatoiy disturbance
in the kidneys, which ]ni<;ht run for (piite a nunibei- of yeai-s.

As the iiriniferous tubules are lined with only a sin«;le layer
of epithelia, a perfect recovery from any attack of nephritis must
depend uj)on the rei)roduetion of the lost e})ithelia from those
which remain. Nothin*; is known concerninji: the reproductive
power of kidney epithelia, and that it occurs is a mere inference.
Patients overcome milder attacks of rafarrhal nephrith ; but the
danger rests in repeated recurrences of this nephritis, which at
length leads to cirrhosis of the kidneys. Kecovery after croupous
nephritis seems in children to be complete — f. i., after scarlet
fever or diphtheria. They sometimes overcome acute haemorrhagic
croupous nephritis of a degree which invarial)ly kills the adult.
Recovery, furtiiermore, is often observed after the nephritis of
pregnancy, probably for the reason that only the right kidney is
the seat of disease. Nephritis produced by certain poisonous
drugs (cantharides, turpentine, etc., often, also, iodine and arsen-
ical preparations) may terminate in a cure as soon as the admin-
istration of the poison is stopped. Even chronic nephritis, with
waxy degeneration, will, if caused by chronic pyaemia, subside
after the removal of the source of suppuration. In such cases of
recovery certain regions of the original kidney-tissue are de-
stroyed, and replaced by eicatiieial connective tissue, produc-
ing a condition of atrophy in those portions, while the greater
part is left unchanged. In most instances of sp(mtane(nis croup-
ous nephritis, however, the disease becomes chronic, with re-
peated attacks of intercurrent acute nephritis, and terminates
finally in a partial atrophy of the kidney-tissue, or a general
hypertrophy of the interstitial connective tissue. Such kidneys
are usually subject to cystic, fatty, and waxy degeneration.
Whether or not the two last-named conditions arise pnmarily,
without any preceding inflammation, I am unable to say.

Acute Ixflammatiox of the Kidneys. By Alfred Meyer, New- York.*

Since Richard Bright, in 1827, drew attention to certain diseases of the
kidneys, in consequence of which severe disturbances of the organism, and

' Abstract of the essay, " I'litersiichunffen iiber ariite Niereuentziiiulung." Sitzungsber.
d. Kais. Aka<1emie il. Wissenscli. iii Wien, LXXV. B<1., 1877. Translated by the author.

48

754 THE VlilXAliY TRACT.

not infrequently tleatli, foulcl be pvodviced, leading pathologists have retained
the designation "Morbus Brightii," and distinguished it from nephritis.
Thus, C. Rokitansky* separates nephritis from Bright's disease. P. Rayer,t
and subsequently B. Reinhardt.t described Bright's disease as a diffuse exu-
dation into the renal tissue. Frerichs v> likewise regarded the designation
'•inflammation of the kidney " as insufficient, and retained the customary
name of " Bright's disease.'" Virchow || was the first to speak of a catarrh of
the ui'inary tubules, and to know that the catan*h could increase to croup —
that is to say, to the formation of a fibrinous exudation in the urinary tubules.
According to him, croup of the urinary tubules is a severer degree of catarrhal
inflammation. As a third form he adopts " parenehjTnatous inflammation"
of the kidney, which depends essentially on a change in the epithelial cells.
In his opinion, catarrhal, croupous, and parenchymatous inflammation can
attack the kidney simultaneously, and for this condition he wishes to retain
the name of " Bright's disease." Herewith, the way was prepared for the
idea that Bright's disease is an inflammatory process, and this view was sub-
sequently adopted by the following authors: S. Roseustein,1I who speaks of a
catarrhal and of a tliff use nephritis ; furthermore, William Aitken ' and J.
Hughes Bennett.* Aitken distingxiishes two varieties of inflammation of the
kidney, in Virchow's sense, — namely, the interstitial, in which, principally,
the connective-tissue stroma is diseased, and the parenchymatous, in which
the urinary tubules are mainly affected. T. Grainger Stewai't^ divides this
disease into an inflammatory, an amyloid, and a cin-hotic form. Ed. Riud-
fleiseh ^ declares premature the attempts of Rayer, Foerster, and others to
draw sharp lines between a simple albuminous, a parenchymatous, an inter-
stitial, and a croupous nephi'itis. He speaks of a desquamative cataiTh, of an
acute parench^kTuatous nephritis, — under which latter head he distinguishes
between a circumscribed purulent, and a diffuse, non-purulent form. In
addition, he speaks of a combination of parenchymatous and interstitial
nephritis. C. Heitzmann ^ asserts that the pictm-e of Morbus Brightii drawn
by Rokitansky includes two different forms, namely, croupous and intersti-
tial nephritis. According to him, the characteristic anatomical feature of
interstitial nephi'itis is the striation of the more or less swollen cortical sub-
stance ; while the characteristic featiu'e of croupous nephritis depends on the
diffuse infiltration, superadded to the inflammatory swelling and redness. C.
Bartels^ divides the diffuse diseases of the kidney into h.\-perfeniia. isehsemia,
parenchymatous inflammation, interstitial inflammation, and amyloid degen-
eration.

This much is clear at the present day, that the designation "Bright's
disease" must be dropped as being altogether unscientific. Virchow's

* " Handlmtli der Pathol. Auatoniie," 1861, 3 Aufl.
t "Trait6 des Maladies des Reins," Paris, 1840.
i " Anualen des CUarite Krankenli.. Berlin, 1850.

i "Die Brijrht'schen Nierenkraiiklieiteii mid ihi-e Bchandluuir,"' Brauusclnveig, 1851.
II " Deber pareneli. Kntziind." Vircliow'.s Arcliiv, 1S52.
V "Die Pathol, und Theiap. der Xiereiikraukheiten," Berlin. l.^^TO.
' " Science and Practice of Sledicine," London, J8t!3.

2 "Principles and Practice of Medicine," Edinhurgli, 1865.

3 "A Practical Treatise on Bright's Disea.ses of the Kidneys," Edinlmrgh, 1871.
J " Lehrhuch der Pathohigischeu (iewebelelire," 3 Aufl., Leipzig, 1873.

^ T'ebeiTiiherkelbiUUuig. Wiener Med. Jahrb., 1874.

fi "Kraukheiteii des Haruajiparates in Ziemssen's Handbnch der .spec. Pathol, iind
Therap." Leipzig, 1871.

77//'; r/.7.v.i/M' ruAcT. 755

attempt to lofiilizt' the iiiHaiiiinatory i)rofe.ssi'H (vvhicli, as generally afjreod,
fctrin till' basis for all tlic Chanel's of renal tissue dfsfribc<l as Hrij^ht's
«liseaso) in the jtrincipal histolo^it-al components of the kidney, namely, in
the tubular epithelium, in the blood-vessels, and in the connecting stroma,
cannot be carried out. I am not familiar with any form of inflammation,
whether of the kidney or of any other {glandular organ, which can begin
and also run its course in oidy a single one of the constituent tissues. Under
all circumstances every one of the histological components is involved in the
jirocess, not only in the mildest catarrhal inflammation, but also in the severe
form of suppuration.

To nie no other method of elucidating the forms of renal inflammation
seems possible than a comparison with analogous processes in glandular
organs in general, whose simplest representatives are the raucous mem-
branes. If we remember that in inflammation the blood-vessels are impli-
cated by the production of an exudate, and the other histological constituents
by morphological changes brought about by nutritive disturbances of the
living matter, we shall have to regard every inflammatory process as a disease
of the tissue in its entirety. Neither the blood-vessels, nor the connective
tissue, nor the epithelium alone can exclusively aflford the substratum of
an inflammatory process, but always these components coineidently. ^Vhat-
ever in the tissue is endowed with life will become active and then produc-
tive during a nutritive disturbance, and only in the case of the death, of the
so-called gangrene of the tissue is the idea admissible that the tissue is
destroyed and remains passive.

In analogy to the varieties of the inflammatory processes in mucous
membranes, we may also speak of a eataiTlial, croupous, suppurative and
diphtheritic inflammation of the kidney. Each of these varieties may be cir-
cumscribed or diffuse : each can gi-adually pass into the other without our
being able to draw sharp lines between them, either with the naked eye or
with the microscope.

We will accordingly retain this principle of di^^siou. The tei"m "croup-
ous nephritis" has been declared to be inadmissible, because the fibrinous
nature of the easts, and hence their identity with the croup membrane of
other mucous membranes has not been demonstrated. True, croup-mem-
brane and casts are neither morphologically, nor mici'oscopicall.v, nor chemi-
cally entirely identical. I shall however, try to explain these differences and
believe that I am justified in upholding the variety of croupous nephritis on
account of all its accompaming conditions. I shall not consider the diphthe-
ritic variety of inflammation, since it mainly affects the renal pehis and
calices.

(1) Tlic Cntarrlidl (JJesfjuamafirc, Interstitial) Xriihritis. The phenomena
which are characteristic of mild catarrhal inflammation in a mucous mem-
brane are oedematous swelling of the connective tissue, swelling and granular
cloudiness of the epithelial covering, and subsequent desquamation of the
epithelium. The blood-vessels which, even to the naked eye. appear filled
and dilated, under the microscope show a more or less complete distension
with blood-corpuscles, without apparent alteration in the structure of their
wall. It never has Vjeen doubted that the oedematous swelling of the connect-
ive tissue and the desquamation are due to a serous exudation from the
blood-vessels, in spite of the fact that the exudation, as such, cannot be seen
under the microscope. The presence of the exudate within the tissue (paren-

756

THE V BINARY TRACT.

ehymiitous ixnd interstitial exudation, Virehow) is to be regarded as an essen-
tial factor of the inflammatory changes, since partly meclianical changes and
partly nutritive disturbances are produced by it.

In more severe and prolonged acute catarrhal inflammation the connective
tissue participates in what is called •' inflammatory infiltration," which leads
to hypertrophy (hyperplasia). It is a well-known fact that the changes in the
connective tissue are accompanied also by changes in the epithelium — viz. :
at first, proliferation, then desquamation, and finally, hyperplasia of the epi-
thelium.

Thus, the catarrhal inflammation in the kidney consists, in the beginning,
principally in changes of the epithelia, subseqxiently in changes of the con-
nective tissue. For this reason, a subdivision into epithelial changes (paren-
chymatous, Virehow) and connective tissue changes (interstitial, Virehow) is
not admissible. Catarrhal inflammation includes, with only gradual differ-

^—M

Fig. ;340.— Acutk Catarrhal Nephkitks. Initial Stage.

t', couvolutetl tuliule; iV, ascending liranch of narrow tubule; 7, interstitial connective
tissue in (edematous swelling; M, beginning of inflammatory intiltration. Magnitied 500
diameters.

ences, the des(iuamative, the interstitial, and also the parenchymatous form
of inflammation described by authors.

I have studied acute catarrhal inflammation in the kidneys of a child- six
years of age, dead of diphtheria, in which symptoms of un^mia had ensued
four or five days before death. The changes implicated principally the cortical
substance. (8ee Fig. 340.)

Some capillaries are choked with red blood-corpuscles and dilated, others
hold a moderate amount of blood. Some blood-vessels contain, besides indis-
tinctly recognizable red blood-corpuscles, a finely granular material, w^hich
coi-responds, perhaps, to what authors call " micrococci." Since the inferences

Till-: rinsAHY ruAcr. 77>7

•Irawn nowadays from the i)ri'si'iu*(' ol siidi niiciucocci in fcrtain I'oi-nis of
nepliritis cannot bt- ii'^^anlod jnstiliabk', I am satisfied with the statement of
the aV)ove condition. Tlie inajoiity of tlie Kl<*'"*'i'idi are moderately enhirged
and tlieir vessels provided witli more abnndant l)odies reseml)linfi nuclei
than normal ; I cannot decide whether these chaiif^es jiroceecled from the inter-
vascular connective tissue (Axel Key) or from the epithelial covering. The
connective tissue around tlu> glomeruli anil between the urinary tubules is
everywhere enlarged, more markedly in the cortical than in the ])yramidal
substance. In the dilated interstices we meet with separated Inmdles of con-
nective tissue, a condition which con-esponds to serous infiltration or oedema
of the connective tissue. At intervals clusters of red blood-corpuscles are
found in the oedematous connective tissue. In some places the connective
tissue is gi-anidar and abundantly provided with nuclear formations, which is
the beginning of interstitial infiltration. The epithelium of the convoluted
as well as of the straight, urinary tubules is swollen throughout. Many of the
convoluted tubules are enlarged and irregularly sinuous, and their central
caliber is reduced to a minimum. In a number of narrow tubules the caliber
has entirely disapi)eared.

The epithelia, especially those of the convoluted tubules, are filled with
coarse graiiules, mostly to such an extent that the nucleus is concealed. This
condition, known as " cloudy swelling," is mentioned by all authors, but its
nature was unknown. In the acute stage of inflammation we have not to deal
with fat granules, which may be proved by simple tests. With high magnify-
ing powers we see that a large majority of the granules within the epithelia are
united by fine threads, and such threads we recognize also in the perinuclear
rim, wherever the nucleus is \asible. Cloudy swelling, therefore, is produced
by a growth of the living matter in the epithelia. As I propose to show later,
we have here the first steps toward an endogenous jDroduction of new ele-
ments.

If the acute catarrhal inflammation from its beginning is not severe enough
to cause the death of the individual ; if, furthermore, it does not affect the
entire kidney, but only disseminated foci, either the desquamative or the
interstitial form of inflammation is more prominent. I had the opportunity
of studying these forms in kidneys of persons who died of tuberculosis, in
whom this nephritis is of almost invariable occurrence. (See Fig. 341.)

The calibers of the capillaries are mostly preserved; their walls, however,
appear reduced to elements analogous to those which fill the surrounding
connective tissue. The glomeruli are moderately enlarged and their vascular
loops concealed by abundant, shining, nuclear formations. They present the
appearance which Klebs described as " glomerulo-nephritis," a superfluous
name in the face of the fact that inflammatory changes of the glomeruli
merely accompany the diffuse nephritic process. It seems that in these
changes the intra-eapsular connective tissue is involved as well as the lining
epithelium. Where the tuft is separated from the cai^sxile, or has fallen out,
we can couvdnce ourselves that the epithelium of the capsule is for the most
part converted into homogeneous, shining lumps, or that the nuclei alone have
undergone this change.

The connective tissue betw'een the lu-inary tubules is widened. Its fibrous
structui-e is retained only in part, while its greatest portion is converted into
variously shaped lumps, partly granular and partly homogeneous, represent-
ing the so-called " inflammatory infiltration." We see that the majority-' of the

758 Till-: CltlXABY TliACT.

uewly appeared elements are miited to each other by fine threads. The
membrana propria of the nrinary tubules remains intact in this stage of the
inflammation.

We find the epithelium in many urinary tubules unchanged or in a condi-
tion of cloudy swelling, while numerous convoluted and straight tubules are
entirely or partially deprived of their epithelium — the dcsquumuUre nephritis
of authors. Wlierever groups of detached epithelia fill the caliber of the
ui'inary tubules, we recognize that the epithelia are smaller and of a more
in-egular form than normal. We encounter round, angular and spindle-shaped
bodies, with and without nuclei, which are, perhaps, newly produced epithelia,
detached from the walls of the tubules by a subsequent serous exudation.
That a reproduction of epithelia really takes place is indicated by the presence
of those peculiar shining bodies which adhere to the otherwise denuded wall.

3

-^

im-

Fig. 341. — Catarrhal Nephritis with PREVAiLixti Interstitial
Inflammation.

i', uiiniferous tubule, lined with irregular epithelia; X», cluster of desciuamated epi-
thelia; X, shilling lumps, from whicli new formation starts; I, cousiderably broadened
interstitial tissue, crowded with inflammatory corpuscles. Magnified 500 diameters.

In the highest degi-ee of catarrhal inflammation, which occurs especially
in the cortical substance, in the bundles of straight tubules, all the constituent
parts of the kidney-tissue have disappeared in the inflammatory proliferation.
(See Fig. 342.) The blood-vessels are no longer recognizable, and not
permeable for liquids injected from without. The connective tissue is strewn
wdth sliining, homogeneous, irregularly shaped lumps ; the membrana propria
has disappeared in many places, so that no demarkation is \isible between
connective tissue and urinary tubules. The latter, especially the }iaiTow
tubules, are crowded (as a matter of coui-se, only in places where no desqua-
mation had taken place, ) with shining, many-shaped lumps, which are stained
a deep red by carmine.

THE rinsMiY thact. 7.')0

Up to th»' i>ri>seiit time tliis coiKlitiun was ovt'ilookcil ]>y all iiivcstitiiitoi-s.
Tilt- I'lmn^it's consist in tiie following: In tlu* epithclia, which Jir« often still
reeogniziiMf by the pri'scni-t' of the irregular ealiher of the fin-nier tubule, the
nuclei or nucleoli, or also single grannies, have Vieen converted into shining,
irregularly shaped, nearly homogeneous lumps, some of which present dis-
tinct imrtition lines. In some tubiiles these lumps are present in small num-
bers, in others they are numerous, and finally the entire epithelium apjiears
converted into such lumps, which are separated from one another by narrow
rims of a cement-substance, but are in uninterrupted continuity with each
other by means of tine threads. This process is a recurrence of tlie juvenile
condition of living matter. As the same process invades also the connective
tissue, the entire structure, especially in the region of the narrow tubules,
appears converted into an indifferent or medullary tissue. From this the pro-
duction of connective tissue proceeds, that leads to cirrhosis and gi-anulation

^^.

Fig. 342.— Catarrhal Nephritis. High Degree. Transforma-
tion OF THE EpITHELIA INTO INDIFFERENT CORPUSCLES.

f, convoIute<l tubule, lined with epithelium iu the stufie of "cloudy swelliug";i,
remnants of nriiiiferous tubules, -whose epithelia are broken up into lioinogeneons. shining
liuups ; I. interstitial tissue, entirely converted into pale granular, or shining indifferent
elements. Maguitied 500 diameters.

of the kidney. It is this pi'ocess — formerly incorrectly regarded as entirely
interstitial — which results iu contraction of the kicbiey-tissue and in the pro-
duction of a more or less uniform granulation of the siu-face. (See Fig. .343.)
If we are to describe concisely the nature of catarrhal iuHammation of the
kidney we should say that in titv fir.st stayv if i-s eJiaractcri-ed by .■^erou.s traiifoi-
dalion into the vonuectire tissitc and cloudy ^-ti-clliny of the epitlielia ; in the .second
stage, by inflammatory infiltration of the connective tissue, desquamation and
reproduction of the epithelium ; in the third staye by a ntetamorphosis of the con-
nectire tissue and of the epithelium into an indifferent or medullary tissue. The
inflammation maybe of a varying degree of severity; its course maybe acute

760

THE riUNABY TRACT.

or suljaeiite ; the characteristic feature always is the serous trausudation, con-
sequently the absence of casts, a variable percentaf;;e of albumen in the urine,
and the presence in the urine of tubular ei)ithelia. The inflamed renal tissue
at no time ceases to be a tissue, hence, no suppuration occurs. The subse-
quent course is characterized by destruction of the epithelia amid continuous
reproduction of connective tissue, and the final atrophy of the renal tissue, re-
sulting in the formation of the small, contracted, granular, or cirrhotic kidney.
(2) Croupous (Parenchymatous) Inflawwatioii of the Kifliiei/. The charac-
teristic feature of croupous inflammation of mucous membranes in general is
the presence of a coagulated albuminous substance on the surface, the latter
being partially or completely denuded of its epitheliimi. The inflammation
of the connective tissue is always a severe one, betokened by intense redness,
swelling, and infiltration with form-elements. Examination with the micro-
scope teaches that the greatest part of the so-called croup-membrane consists

Fig.

343.— Catarrhal Nephritis. High Degree. Transforma-
tion OF THE Epithelia into Indifferent Corpuscles.

C, convoluted tubule, with coarsely granular epltheUa ; J?, remnants of a tnbnle, vrithont
ilistinct boundary toward tlie interstitial tissue ; the epithelia liold shining, liomogeneous
lumps: i, the epithelia entirely broken up into shining, homogeneous lumps ; recurrence of
the juvenile condition; I, insterstitial connective tissue in a similar condition. Magni-
fied 800 diameters.

of a dense net-work of coagulated fibrine, in which var\-ing numbers of bodies
of the aspect of nuclei are imbedded. A similar net-work is also invariably
found in the air-cells of the Imigs in croupous pueumoiiia. and the absence of
coagulated fibrine is regarded as an important feature of catarrhal pneumonia.

The question as to the origin of the croup-membrane has been answered
in different ways. Wliereas some regard the entire mass as a coagulated
exudation from the blood ; others (Yu-chow, E. Wagner) believe it to be a
direct jn'oduct of epithelia, and others again explain the presence of plastids
within the croup-membrane by supposing an extensive emigration of colorless
blood corpuscles.

If we take into consideration that a fluid exudate before reaching the sur-

Till-: rinsAUY thact. Tiil

face irmst pass tliroiiijh tlif walls of tlii' vcsst-ls. tliroiij^li the coniicctivt' tissue
intervoiiiuj,' iK'twt't'ii vcsst-ls and ciiitlicliiuii, and liiially tlirouf^h the fpitliolia
thenisi'lvcs, it is evidt'iit tliat every superficial exudation, before bccomiiit;
free, must luive been an interstitial and a j)an'n(diyniatous one. Tlie f1ui<l
coiniiifj from the blood, is taken up ))y the living epithelia, and may lea<l to
chancres such as were descrilied by E. Wa}^ner, but also to the destruction of
the epithelia. After the union of tiie tyrannies of liviuf^ matter is broken, the
granul«>s themselves are iml>edde<l in thecoaf^ulatiiif^ exudate, or are converted
iuto an albuminate no longer viable. This change may occur in the epithelia
as well as in the connective tissue after dissoluti<jn of the basis-sul)stance.
There is nothing to hintler the supposition that with the exudate formed ele-
ments of the blood emigi'ate, and, after being entirely or partially changed,
lie imbedded in the now coagulated mass. It is evident that epithelia alone
cannot produce a croup-membrane, but require the presence of an exudate
from the l)lood, and the essential constituent of the croup-memlirane, under
all circumstances, is the coagulable albuminoid body from the blood.

If we apply to the renal tissue the experibnce gained in other mucous
membranes, it follows that the characteristic features of a croupous nephritis,
in Traube's sense, consists in the presence of casts. I mean the products
known as hyaline and gi-anidar casts to which epithelia from the tubules may
adhere. The waxy, shining casts may be formations which have undergone sec-
ondary changes. These bodies were seen for the first time in 1 842 by Henle,
and declared to befibrine. This view was shaken by Rovida,* who stated that
the colorless and yellow casts could neither be fibrine, nor gelatine, chondrine,
mucine, hyaline, or other colloid substance. Kovida admits, however, that
casts possess certain properties of the proteinates which permit their being
regarded as derivations of an albuminous substance. According to Axel Key
and Ottom. Bayer the casts have arisen from a degeneration of the tul)ular
epithelium and a coalescence of epithelia thus degenerated ; both investigators
are cognizant of the fact that in tubules which are obstructed by a east the
epithelial lining is present nearly every time and remains intact for a long
while. It will scarcely be necessary to go into particulars regarding the secre-
tion theory, since after what has been said the exudation from the blood must
under all circumstances pass through the epithelia.

C. Bartels t declares that clinical experience conipels him to adhere to the
older view concerning the origin of certain forms of easts — namely, that
casts are produced by the coagulation of an albuminous substance. This
supposition is based on the experience that the presence of casts in the urine
depends upon the admixture of albumen with this secretion, since, firstly, such
casts are found in the urine in conditions accompanied by albuminiu-ia ; and
secondly, in the gi'eat majority of cases, coincidently with the albumen, casts
also appear in the urine. Bai'tel's %aews agree with my experience, both
clinical and microscopical. I have not seen casts in urine that was free from
albumen, but I have quite frequently examined albuminous iirine in which
casts were not demonstrable. The more abundant the albumen in the lu-ine
was, the more certainly could I expect to discover casts, and wherever I had
an opportunity to examine kidneys post-mortem which had excreted urine
rich in albumen during the life of the patient, and where there had been
symptoms of an acute inflammation of the kidney, every time I encountered

- " Ueber das Wesen rter Harncj'linrter. Molescliott'.s XJntersuclnuigeu," XI. Barirt.
t Zieni.ssen's " Hanilbiich der spec. Palhol. und Tlieraj)."

762 THE UlUXATiY TBACT.

a severe degree of iiiHaniiiuitory cluuiges whicli, on account of the presence
of the casts within tlie tubules, niiglit be called crouj)ous, in the sense of
Henle and Traiibe.

The condition of the kidney of a man, thirty-seven years of age, who died
with symptoms of uraemia, on the sixth day after the extirpation of an orbital
tumor, is the following : The kidneys increased in size by one-half their bulk,
rich in blood, of a doughy softness ; the capsule easily stripped ; the surface
.markedly injected ; the cortical substance twice as broad as normal ; the border
toward the pyramids indistinct. The whole tissue, especially that of the corti-
cal substance, of a nearly homogeneous, grayish-red color, evacuating a thick,
gi'ayish-red, cloiidy fluid when its cut surface is scraped with the knife. The
glomeruli appear enlarged, even to the naked eye, and are of a dark red color.
Under the microscope the blood-vessels appear dilated, partly tilled with
blood. The arteries (especially their middle coat), are widened, the muscle-
fibers in part coarsely gi-anular, in part converted into homogeneous, shining
layers. The glomeruli universally enlarged, their vascular loops dilated, the
vascular walls shining and nearly homogeneous ; the connective tissue between
the loojjs widened, provided with shining gi-anules and lumps. The capsule
and the interstitial connective tissue have for the most part lost their striated
character, and appear granular, dotted with numerous, partly homogeneous,
partly coarsely granular lumps.

The urinary tubules present changes, as in catarrhal inflammation — the
convohited tubules enlarged and wound ; their epithelia in a condition of
"cloudy swelling," in pai't detached from the wall, and lying free in the
lumen ; in many places the epithelium broken up into yellowish, shining
lumps. Moreover, the epithelia of many convoluted and straight tubules pre-
sent changes which m^lst be regarded as characteristic of croupous inflam-
mation. The epithelia are swollen up to a complete closure of the lumen ;
they are converted into globules or plates of a faint luster, which, pai'tly coa-
lescing, represent iiTegular, caky masses. Finally, all the epithelia of a tubule
appear changed into such a mass, in which even the outlines of the former
epithelia are recognized ; these are the tubular casts. Hyaline or finely
granular casts are colorless in the fresh state, and are readily stained by car-
mine, while, more particiilarly in the narrow tubules, granular, yellowish plugs
occui" which do not imbibe the carmine. Since plugs of the latter kind are
also to be observed in blood-vessels, nay, even in single loops of the tufts,
there can be no doubt that they are albuminates, being essentially the same
as the fluid portion of the blood, and stained yellow by the coloring matter of
the blood. Wherever the epithelium has gone through the process described,
small, shining, spindle-shaped projections are visible on the membrana pro-
pria, in part distinctly separated from the caky mass ; and where the forma-
tion of a hyaline cast is complete, we almost constantly meet with a narrow
epithelial layer, composed, in the optical section, of spindles.

Many convoluted tubules contain hyaline casts, the epithelium of the
tubules being only slightly changed or desquamated. It is probable that these
are casts which have not been formed in situ, but were washed down. Where
the cast adheres closely to the wall, the epithelia are either not recognizable,
or we see irregular projections of the wall or flat bodies quite irregularly
arranged. (8ee Fig. 344.)

How did the casts originate 'I Since changes such as described in the epi-
thelia of the uriniferous tubules occur also in the interstitial connective
tissue, and even in the blood-vessels, there can be no doubt that the exuda-

THE rniSAHY TUACr.

JiV.S

tion foiniii^ from the blood, if taken up l»y tin- tissues in sufficient (pmiitity,
and of ii certiiiii (|uality, leads to the swellinj^ up and death of the living mat-
ter. The exudation, originally fluid, but coagulated soon after its passage
from the vessels, will contain the altered or lifeless i)art of the tissue. The
result of the coagulation is the formation of hyaline or, also, of gi-anular casts
in the tubules, an<l of granular and yellowish hyaline plugs in the blood-
vessels and narrow tubules. The casts are products of an albuminous exuda-
tion from the blood-vessels, plus the swollen up and destroyed epithelia.
This \iew is supported by the api)earance of the vascidar Ioojjs within the
tufts: here the vascular wall is converted into a homogeneous, shining mass,

Fig. 341. — Acute Croupous Nephritis.

D, uriuil'eious tubule, with detaclied epitlielium ; L, tultule whose epitlicliuni is couvt-rtcd
into indiffert-nt elements; T, tubule lioUliuf? a hyaline cast, which iirobably was washed
down from some other part — the eiilthelium in part desquamated: I, interstitial tissue,
broadened and crowded with inflammatory corpuscles. Magnified oOO diameters.

which is deeply stained by carmine and exactly corresponds in appearance
with the casts.

Under certain circumstances the epithelium of the tubules may partially
or totally disappear in the mass which we term tubular cast ; but there is
always a rapid reproduction starting from those lumps of living matter which
adhere to the tubular wall. On the inner coat of the membrana propria w^e
meet with all transitions from yellowish lumps up to the formation of flat
epithelia covering the cast.*

' Later observations have led to the conclusion that the flat plastids, which are spindle-
shaped in edge-view, are no epithelia, but the endothelia belonging to the so-called membrana
propria of the tubule. With this view the formation of a cast is satisfactorily explained.
— Ki>.

764

THE U BIN A BY TBACT.

The changes just described I was also enabled to see in the tubules of
another kidney, in tlie immediate neighborhood of small forming abscesses.
The circumstance that at times formations resembling nuclei are imbedded in
the cast is comprehensible, if we consider that the epithelial body may disap-
pear in the formation of the cast and the nucleus be left unchanged. Granular
easts are probably formations in which the epithelia have not yet undergone
such extensive changes as are requisite for the production of perfect hyaline
casts. Yellow casts are the result of the imbibition of the coloring matter of
the blood by the coagulum. Waxy, shining casts may be secondarily changed
products, the same as casts which are abundantly provided with fat-grauules.
(See Fig. 345.)

Not infrequently we observe combinations of catarrhal and croupous
nephritis, in which cases abundant desquamated epithelium is to be found in
the urine, but only a few hyaline casts. As, according to the above advanced

Fig. 345. — Acute Croupous Nephritis in the Neighborhood
OF A Forming Abscess.

(', tubule iu transverse section, filled by a hyaline cast ; E, tubular epithelia at the
beginning of proliferation ; /, interstitial connective tissue crowiled with inflammatory
corpuscles ; their rows probably corresponding with former blood-vessels. Magnified 1000
diameters.

views, all forms of inflammation present only gradual differences, further-
more, even in diffuse nephritis, the kidney is never uniformly diseased
throughout its substance, but rather in foci, I believe that the presence of a
few casts, especially in the narrow tubules, when accompanied by catarrhal
changes in the epithelium of the convoluted tubules, is easily explained. The
most numerous blood-vessels run in groups along with the narrow tubtiles.
Here, accordingly, the inflammation can easily reach a higher grade than
in the region of the tufts and of the convoluted tubules. This also explains
why, after healing of croupous nephritis, irregular cicatricial retractions apjjear
on the surface, between which there are coarse elevations of a comparatively
little changed kidney tissue. After croupous nephritis the contraction is
always irregular and deep, not leading to a granulation of the surface. The
large, fatty and amyloid kidneys are probably always products of secondary
changes after an original, acute, croupous nephritis.

iiiK riiisMiV ruAcr. Tfi.')

(|{) Siiiipnratirc liitlaimiititidii of llir hidm ;/. 'I'lic (lucstion as to the orif^iii
of pus in absoi'ss of the kidney lias onjja^cd tlic attention of several inves-
tif^ators. In ISTi'J, already. (Jeorj^e Jolinson oljserved the transformation of
the epithelium into pus, espeeially in the kidney-tissue, notwithstandinf^ his
bein^ a stronj^ humoral patholoj^ist. Lipsky * has produc^ed purulent foci in the
kidney experimentally, and asserts tluit the oj-ij^in of tlie j)us-cori)Usck's is to
he soufjcht for in tlie epithelium of the uriniferous tuljules, by division and by
endogenous eell-proliferat ion.

In eousidering the faet that the interstitial eoniieetive tissue, as well as
the epithelium, has abundant living matter, it is plain that in nutritive dis-
turbances the living nuitter of the tissue in its entirety nuist undergo changes,
and accordingly take part in the process of inflammatory proliferation. Cohn-
heim's idea that in the inflammatory process an active part is to be ascribed
exclusively to the colorless blood-corpuscles, must be regarded a failure.

I have studied the microscopic appearances of suppurative nephritis in the
kidney of a man who died with uraamic symptoms caused by hypertrophy of
the prostate, which was followed by suppurative cystitis, sui)purative pyelitis,
and finally, suppurative nephritis. The kidney, especially the cortical sub-
stance, had numerous abscesses the size of a millet to that of a hemp-seed.

At some distance from the yellowish pus-foci, which were just recognizable
with the naked eye, the blood-vessels, especially the veins, appeared filled to
repletion with blood, dilated, while the capillaries only in part have remained
recognizalde. Many tufts were enlarged and their vascular loops provided
with numerous coarsely gi-anular nuclei. The interstitial tissue was partly in
the condition of oedematous swelling, partly sprinkled with groups of yellow-
ish, shining lumps. The epithelia appeared in the condition of cloudy swell-
ing; their cement-substance had mostly disappeared, so that many uriniferous
tubules were filled with a coarsely gi'anular mass, in which numerous partly
homogeneous nuclei were imbedded. Thus, wo observe the features of
catarrhal nex^hritis.

In the neighborhood of many piu-uleut foci the picture of a croupous
nephritis is i>resented.t We find most of the iiriniferous tubules filled with a
hyaline mass, readily stained with carmine ; the surrounding epithelial layer
in the form of lenticular, flattened-in transverse section spindle-shaped, bodies.
The nearer we approach the pus-focus, the more the interstitial tissue ap-
pears filled with round, shining lumps, at the same time widened and lack-
ing blood-vessels. The epithelia of the tubules ai'e converted into irregular,
•shining lumps, or provided with coarse granules, which show marks of di\-i-
sion, and, by the manner in which they are grouped, indicate their origin from
larger lumps. From the homogeneous lumps up to the coarsely gi-auular
nuclear products all intermediate stages may be traced, iiutil all the epithelia
appear converted into such nuclear formations, which, in part, lie closely
together, in part are separated from each other by granular bioplasson. The
membrana propria is still recognizable in this stage, and distinctly marks the
tubule fi'om the connective tissue, which frequently contains extravasated
red blood-corpuscles, beside similar formations.

Finally, we reach the suppiu-ative focus. (See Fig. 34G.) Here the entire

■■■■ Wiener Med. Jalirb., 1872.

f Later observations have demonstrated that tulnTeulosis of the kidney is invariably
accompanied by catarrhal nephritis, whih' suniiuration -the prodiution of an al)sce8s — is
ax;conix>anied bj' croupous neidnitis.— En.

766

THE UlilNAnY TliACT.

interstitial tissue is sparsely traversed by unchanged fibers, but mainly con-
verted into a gx'anulated mass, in which only globular, shining, or coarsely
gi-anular nuclear bodies, but no isolated elements, are recognizable. The
niembrana propria is still partly preserved, and we thus ascertain that the
epithelium of tlie tubules has broken up into bodies resembling in every par-
ticular those of the connective tissue.

While some suppurative foci are composed principally of homogeneous
lumps, which cannot be considered as completed pus-corpuscles, other foci
are made up of coarsely graimlar bioplasson, in whicii, at nearly equal inter-
vals, nuclei are imbedded. In neither of these cases has a disintegration of
the tissue into ijus-eorpuscles taken place. Foci, on the contrary, which con-
tain fluid pus, already recognizable by the naked eye, under the microscope
also present nothing but aggregations of isolated pus-corpuscles. The loops
of the tufts also take part in the production of pus, iiuismuch as the walls of

Fig. 346. — Suppurative Nephritis.

7', lomuaiit.s tti luiuitcrous tubules, whose epithelia are coalesced into nuiltiuuclear
masses; their Ijouudary line in part destroj'eil by the inflammatory iutiltratiou: 7, intersti-
tial tissue, almost completely converted into iuttanuualory corpuscles ; all blood-vessels
destroyed. Tiie brealvin^-up into sinjiie pus. corpuscles not yet accomiilislu^d. Magnified 500
diameters.

the vessels at first split into shining lumps and subsequently into pus-
corpuscles.

The course of suppviration is, therefore, the following: In the first place,
it is clear that interstitial tissue, as well as ei^ithelimn, can be converted into
pus ; the living matter of either of these tissues may return to the juvenile
state, the granules becoming enlarged, homogeneous, and shining. We notice
groups of such lumps scattered throughout the interstitial and the epithelial
tissue. (See Fig. 347.)

THE riUSM!Y IliACi:

767

Next, witli ill) iiicrcasiii}^ miiiilifr (tf tlicsr liiiii|t,s, tlic tissue //( /'</« ;ii)i)('ars
convertod iiilo a coiifjloiiu'ratc of shiiiiiit< luiiips, and finally, a (lilTcicntiation
into nnt'leatetl corpnsck's takos j)lac(', rcprcscntinf^a staf^c in wliicli the former
tissue is still a tissue, thouj^h niarktMlly altered. Only when the continuous
mass is torn into separate, nucleated lunii)s liave we to deal witli finished pus.
The tissue is destroyed — in its place we have an abscess.

The endogenous proliferation of living matter takes place in exactly tiie
same manner in connective tissue and in epitlielium. The division into single
elements is always a secoiulary process, and can occur in every stage of the
l)roliferation. Homogeneous lumps l)reak up into a number of gi-anides by
the formation of new lines of division within the lump. In the Ijeginning
every lump and every gi-anule is united to all its neighbors by fine threads.
Tlie li\ing connection is retained even after nucleated bodies have formed
from the lumps ; the connection is broken after the formation of pus-
corpuscles.

Fig. .'547. — Suppurative Nephritis.

C, iiiiiiifcrous tiibuli', tilled with a cast, iu wliicli vemuaiiLs of nuclei are iinbeiUlfd ; Z,
tubular epithelium, in active new formation of liviuu: matter, iu the early stages of endoge-
nous formation of i)us-cori>uscles ; V, red blooil-corpuscles, partly in vessels, partly extrava-
sated in tlie interstitial tissue, which holds a number of coarsely granular corpuscles. Magni-
fied 800 diameters.

Chronic Inflammation of the Kidneys. By Jeannette B. Greene, M. D.*

In accordance with the plan pursued in the laboratory of C. Heitzmann
for the last seven years, we divide chronic nephritis into three main varie-
ties, namely, the catarrhal, the croii)>ons, and the siijipuratirc. All these
varieties of nephritis may appear in the acute form also. Chroiue catarrhal,
and croupous nephritis may be accompanied by acute recurrences of the
disease, and in this way give rise to a secondary subacute condition.

It is unnecessary to say that stich terms as "catarrhal" and "croupous"
liave no special significance ; but, after having been once adopted iu our
I'riuted frowi tlie autlior's mauuscrix)t.

768 THE UmXARY TRACT.

nomenclature, they may be preserved, and certainly are to be preferred to
such expressions as " interstitial," "desquamative," or " parenchjTnatous "
nephritis, which were introduced by Virchow. In nephritis, as in every inflam-
mation, the morbid process starts fi-om the vascularized connective tissue,
while the participation of the epithelia is only secondary. Every form of
nephritis must, therefore, fi-om necessity, be interstitial and parenchymatous
at the same time.

The term " Bright's disease," 1 think, ought not to be employed by any
scientific person, for it has no significance, and the gi'oup of morbid phenom-
ena considered under that head include both the primary and secondary
changes of the kidney-tissue.

( 1 ) Chronic ( 'aUirrhal Xephritis. We know that in certain forms of nephritis
the urine contains no albumen, or very little, which may, however, be tem-
porarily increased; that it contains kidney epithelia detached fi-om the con-
voluted and the straight tubules, pus- and blood-corpuscles, and occasionally
a hyaline cast, usually fi-om the narrow tubes. The clinical features of the
disease are widely different in different individuals. In cases of this kind
death may ensue and the kidneys exhibit the appearances described in the
preceding article. Shovdd the disease, on the contrary, be prolonged for
several months or years, the result of this chronic action is foimd to be a
shi*inkage of all the kidney-tissues, and this condition is briefly termed cir-
rliosis. Chronic catarrhal nephritis andcirrliosis are therefore identical.

In the milder forms of this disease the siu"face of the kidney is irregularly,
though slightly retracted. The capsule is in most cases adherent and fol-
lows the inequalities of the retractions. The diameters of both the cortical
and pyramidal substances are somewhat decreased, and all parts of the kidney
«how, even to the naked eye, grayish radiating strife. Under the microscope,
wth low powers the strife prove to be nev,-ly formed connective tissue, which
is most abundant in the medullary rays of both the cortex and the p^Tamids,
and it is the retraction of this newly formed tissue which causes the irregu-
larities of the surface. In the more severe forms of chronic catarrhal nephritis
the whole kidney is considerably reduced in size and the inequalities on the
sui'face are very decidedly marked. In transverse section both the cortical
and pjTainidal substances are seen to be much narrower than in the nonnal
condition. This is more particularly the case in the cortex, of which, in more
advanced degrees, only slight remnants are left, and these correspond with
the elevations of the surface. It is further observed nuder the microscope
that the newly formed connective tissue is most developed corresponding with
the medullary rays, between the straight, narrow tubules, which are reduced
in number. Injected specimens of cirrhotic kidneys show plainly a deficiency
of blood-vessels in the medullary rays of both the cortex and pjTamids. The
capillary reticulum around the tufts and tubules is also scanty. The calibers
of the capillaries are in many places irregularly distended, and the vasa recta,
which ai*e capillary prolongations extending into the pyramidal substance, are
naiTower than the normal vessels. At the points of transition of cortical
capillaries into vasa recta, the difference in their respective calibers is less
marked than in the normal kidney.

The question now arises. What are the changes which take place in the
kidney-tissue, producing destruction of tufts, tubules, and blood-vessels, and
gi^dng rise to such an extensive new formation of connective tissue m their
stead ?

Till-: I RISMtY TliACT. 709

I Hin able to t-orrohorato tlie Htatt'iiUMit inadc by A. Meyer, tliat in the
process of oaturrhal nephritis in the eortieal substance many tubules are
destroyed, and that their ej)ithelia, after a considerable increase of living
matter, break down into medullary cprjjusdes, from vvliich a new formation of
connective tissue subsecjuently arises. This destructive process in chronic
catarrhal nejjhritis invades first — and in the hifjhest (lefn'<'<' — tlie narrow
tubules runniufj in the nie(lullary rays. By a swelliiiff of the epithelia the
calibers of the tubules are ol)literated, the epithelia then break down and
form rows of medullary corpuscles. A coiTCSponding change takes place in
the capillary blood-vessels in tlie neif^hborhood. These metamorphoses result
in tlie fornuition of a tissue, which, from the presence of basis-substance,
must be rej^arded as connective tissue, tlioufjh it rarely becomes fibrous, and
the vascular supjily is always scanty. If a number of tuluilesin the medullary
rays are involved in this destructive process, the surface of the kidney con-e-
spondiiif; to them will be retracted by the cicatricial tissue.

The obliteration of a niunber of the narrow tubules, including the ascend-
ing and descending branches, would explain the clinical fact that y^ersons
afifected with cirrhosis void large quantities of urine almost destitute of salts.
Ve know, from the results of Bowman's investigations, which have recently
been corroborated by R. Heidenhain, that the tuft excretes water only, and
this becomes thicker by the addition of the saline constituents excreted by
the narrow tubules. It is in the narrow tubules that much of the watery part
of the urine is restored to the thickened blood which runs in the neighbor-
ing capillaries, including also the vasa recta of the pjTamids. K the function
of the tubules be much interfered with, the interchange between the liquid
contents of the tubes and the solid constituents of the blood will not
take place, and consequently the urine will be voided in about the same con-
dition in which it was pressed into the capsule from the tuft. Numbers of
the convoluted tubules perish also through the increased formation of connec-
tive tissue, while from others the epitlielia are simply desquamated, and,
together with pus-corpuscles, which are the offspring of epithelia, appear in
the lu'ine. Both the quantity and the character of the urine, as well as its
morphological elements visible under the microscope, enable us with cer-
tainty to make a diagnosis of cirrhosis of the kiilney.

From the above description it is evident that interstitial and desquama-
tive nephritis are concomitant features of chronic catarrhal nephritis, and
that the latter expression includes the two former.

In high degi-ees of cirrhosis many of the tufts are completely destroyed.
I have been able to trace the changes by which the destruction is brought
about. At first the tuft appears slightly enlarged and crowded with bodies
having the appearance of nuclei, and which undoubtedly originated from
the covering epithelia and fi'om the endothelia of the capillary walls. By
this process the calibers of the vessels are obliterated, and all that remains
of the former capillaries is a solid cord. Next the solidified capillaries break
down into medullary or inflammatory corpuscles, and in this stage the tuft
consists of an aggregation of inflammatory corpuscles. The capsule is usually
considerably thickened, and between it and the inflammatory bodies no
space can be recognized. In the succeeding stage the medullary corpuscles
are transformed into homogeneous or faintly striated connective tissue
containing only a very limited number of plastids.

49

770

THE UmNAEY TliACT.

After passing through these changes the tuft is reduced to a half or a third
of its original size. The capillaries remain only as radiating strings, and
these, with the altered capsule, admit the diagnosis of an atrophied and
solidified tuft, which is often found to he in waxy degeneration. Sometimes
around the atrophied tuft, consisting of a solid mass of connective tissue, a
light space is observed, traversed by delicate fibers and remnants of the
epithelia of the tuft and the capsule. This is a newly formed, probably
myxomatous basis-snbstajice, which is produced by medullary corpiiscles,the
offspring of the glomerular epithelia. (See Fig. 'i4S.)

In a more acute course of the disease, the tuft, together with the capsule
and all the surrounding tissues, including interstitial connective tissue, blood-
vessels, and convoluted tubules, break down into a mass of inflammatory
corpuscles, resulting in an extensive new formation of connective tissue, or a

Fig. 348. — Cirrhosis of the Kidney. Atrophied Tuft,

T, tuft, transfornieil iuto fibrous t-ouuective tissue: J?, lemuants of epillielia ot the tuft .-
/S', structureles.s, newls' formed basis-substaucc ; E, reuinants of eiutlielia of tin- capsule ;
C, considerably thickened capsule. Magnified 500 diameters.

formation of cysts. Apijareutly an already atrophied tuft may in an acute
recurrence of nephritis break down into inflammatory corpuscles, and at last
disappear entirely. From this description it is evident that the term "glom-
erulo-nephritis," introduced by Klebs, is superfluous, for the inflammatory
changes of the tuft are invariably connected with general nephritis.

I have also made examination of the changes which, in chronic catarrhal
nephritis, take place in the arterial coats, and which result in the destruction
of even large arterial vessels. (See Fig. 849.)

The first thing noticed is that the lining endothelia of the artery are en-
larged and coarsely granular, and that a proliferation of inflammatory corpus-

'/'///•; r/.7.V.l/.')' TliACT. 771

eles takes place, eiRToaeliiiiK upon the caliber, reiiileriiifj it irrcf^ilar, as if
coniju-essed. Often, however, tlie luirrowed lumen contains a finely f^anular
or homogeneous mass, pH.bably plasma of the blood. The spindl^^s of the
smooth muscle-tibers of the middle coat are transformed into inflammatory
corpuscles. These bodies, at first, are not numerous, but, in more advanced
stages, appear to compose the entire tissue, which still preserves a resem-
blance to the original smooth muscle-structure. These characteristics are
jtarticularly well marked in transverse sections, where a decided increase in
the circujuference of the vessels is also noticed. Similar chauges take place
in the external coat, till finally the entire arterial wall is converted into a
solid connective-tissue cord, which may, in places, still show faint traces of
the former caliber. Cords of this kind, as a general thing, i)resent the feat-
ures of waxy degeneration.

(2) Chronic Croupous Xcpliritis. The clinical features of this form of
nephritis are somewhat different fi-om those attending ciiThosis.

■E

Fig. 349. — Cirrhosis of Kidney. Inflammation of an Artery.

E, endothelia iu active proliferation, the caliber considerably narrowed ; yf, middle coat,
the smooth muscles iu part transfoimed into rows of inflammatory corpuscles; A, adventitial
coat, crowded with iuHamniator}' corpuscles, partly sprunfr from the capillaries of the adven-
titia. Maguitied 600 dianu'ters.

In chronic croupous nephritis symptoms of tu"a?mia are more common than
in the cirrhotic form, and sudden death is much more frequent. The urine
invariably contains casts and albumen ; the former are usually granular, and
waxy or fatty if the corresponding changes have taken place in the diseased
kidney. Hyaline, epithelial, and blood casts may also appear in addition to
those first enumerated, if an acute attack of inflammation is superadded to

772 THE ruiXAin' rnACT.

the existing chronic affection. In persons dead of chronic croupous nephritis
of long standing, the kitbiey is found to have an entirely different appearance
from the cirrhotic kidney. It is more frequently enlarged than diminished in
size. The surface is often nodulated, and between the nodules are seen deep
cicatricial retractions. These retractions are never found uniformly over the
sirrfaee. The capsule is adherent to the retractions. In transverse sections
of a kiibiey of this kind we find that the cortical substance is absent in those
parts corresponding with the retractions of the surface, while in other places
the cortex may be unaltered, or even increased in bulk. The pyramidal sub-
stance may be unchanged, or it may be diminished. In contradistinction to
the more or less uniform shrinkage of the kidney — called cirrhotic — the par-
tial destruction of the tissue which occurs in chronic croupous nephritis
might be designated atroplnj ; for, under the microscope, we find in the most
diseased portions only traces of the original kidney structure.

Cysts are found to be larger and more numerous in kidneys affected with
chronic croupous nephritis than in those which are contracted and reduced by
cirrhosis. Both fatty and waxy degeneration are met with in cirrhotic as well
as in atrophied kidneys, but these changes are more extensive in the latter
than in the former. In the so-called " large, white kidney" the highest
degrees of fatty degeneration occur as a secondary result of chronic croupous
nephritis. The " lardaceous " change is also a secondary condition of this
form of nephritis.

In sections of the depressed cicatricial portions of the cortical substance
of kidneys in chronic croupous nephritis, we find a large amount of connective
tissue, which may be either homogeneous or fibrous, and which has only a
scanty supply of blood-vessels. In the cirrhotic kidney the newly formed
connective tissue is more or less regularly distributed throughout the kidney
sti-ucture. The uriniferous tubules are in part transformed into connective
tissue, while still retaining the outlines of their original configuration. In
atrophy of kidney, on the contrary, there is no regularity in the arrangement
of the connective tissue, and we find only remnants of the former tubules.
We further observe in these latter cases irregularly scattered sections of
tubules, from which the epithelial lining has entirely disappeared. Other
tubules, still recognizable by their shape, are crowded with inflammatory
bodies, which have evidently arisen from the tubular epithelia in the forma-
tive stage of connective tissue. The connective tissue, more particularly in
the subacute forms of croupous nephritis, is often observed to be filled with
inflammatory corpuscles : and in the midst of groups of these bodies of the
ordinary color, and readily taking the carmine stain, we also find aggregations
of corpuscles, light brown in color, and unaffected by the carmine. I am
inclined to regard these formations as the offspring of the former epithelia of
the tubules. ( See Fig. 3.oO.)

Not infrequently, in the middle of these brownish clusters, hyaline casts
may be found ; these probably originated in the convoluted tubules of the
first order, and were too large to be carried through the narrow tubules.
What the ultimate fate of these casts may be, we can only surmise. The
tufts, as in cirrhosis, are reduced to a mass of medullary corpuscles, and a
similar change takes place in the surrounding capsule. These facts lead to
the conclusion that a destruction of the epithelial and vascular structures
takes place, with the final result of a new formation of connective tissue.

In the highest degrees of chronic croupous nephritis, in addition to the

rilK I HIS AH Y lliACT.

ra

atropliicil portions we find distrifts wliero a coiisi(lei'a))le Hiiiouiit of coiinoct-
ivi> tissue lias (lev('lo])e<l, thus coiistitutinga true lii/ixrtrophi/, or liifjHr/tlaski.
Tliis tissue surrounds tliov tubules, whieh in a majority of cases are entirely
witliout epithelia. The e]>ithelia may have been carried away by simple des-
(juaination, or have perished in tii(> fonnation of casts. In many of the narrow
tuliuh's, from whiidi tlie epithelia have disappeared, we fiml a row of narrow
endothelia, iletached in j>laces from the connective-tissue wall. A kidney of
the above description may with as much proj)riety bi- called hypertrophied
as a lunij or a f^iandular orfjau in a like condition. (See Fig. Mol.)

Concerniuf^ the formation of casts, my observations convince me that the
epithelia lining the tul)nle, becoming saturated with the albuminous exudate,
swell, grow pale, and tinally jtrodiice the mass called a tubular cast. In many
cases the cast has the appearance of having been constructed of a number of
hyaline or granular lumps resembling former epithelia. Around the cast, at

C, indistinctly fibions couuective tissue ; /, cluster of mi'duUiuy corpuscles, spruuix fioiu
former tubular epithelia ; T, tubule, deprived of its epithelia ; Jf. tubule, containing a granu-
lar cast. Ma.Hiiitied (!0() diameters.

its place of origin, we almost invariably see a wreath of endothelia lying
between it and the wall of the tube, inilicating that after the formation of the
cast a reproduction of endothelia had taken place, or that they had been
brotight into view by the liquefaction of the hyaline, so-called basement-mem-
brane. The presence of this endothelial wreath seems to be satisfactory
proof that the cast was formed in the situation where we find it. If a cast
is seen not quite filling the caliber of the tubule which is still lined with
unchanged epithelia, the most reasonable presumption is that it has been
transported to its present locality from a narrower part of the uriniferous

774

THE UlilNABY TliACT.

tubule, where it imist have orijijinated. The same may be said of casts found in
tubules entirely stripped of epithelia, whose calibers are broader than the
diameters of the casts. It cannot T)e denied that a mass closely resembling
a hyaline cast may be produced from cndothelia; for I have seen such irregu-
lar formations lying along the border of a tubule bounded toward the center
of the caliber by a row of epithelia, which had been detached by the exudate
and undergone no cliangc. Formations of this kind are, however, very
exceptional.

In chronic croupous nephritis granular easts are commonly found to be
more abmidant tlian other varieties, the gi-anules being probably due to a dis-
integration of the ensheatliing endothelia. Fatty and waxy casts are also

■"^siii^

Fig. IMI. -Hypertrophy of Kidney, after Croupous
Nephritis.

C, granular cast, lioldiiis in its c(;iiter wax.v Iniiips ; £, eiulotliclial liniun of the tubule
around the cast; T, empty tubule; /, interstitial connective tissue, with injected blood-
vessels, holding a moderate number of inflarauiatoi-y corpuacles. Magnified GOO diameters.

featiu'es of this form of nephritis ; these always indicate a similar meta-
morphosis in the kidney-tissue itself.

(3) In chronic suppurative uephritis abscesses formed in the kidney may
exceptionally lead to the production of a dense connective-tissue capsule — the
" pyogenous membrane" of writers — and pus, imder these conditions, be-
comes inspissated into a cheesy mass, which, by some, has been mistaken for
tubercle.

A formation of this kind may be termed a chronic absccsx of the kidney,

THE riiiSAny tkact.

775

and has nothinp; in oonimon with tubercle, except that, the watery portions
having Ikhmi absorltcil. the ])Us-corpu.scles shrivel and become partly trans-
t'ormetl into tat-<;ranules. In tiie caseous and fatty degenerations of tubercle
we observe an analogous result, the cause of these jirocesses being identical
— /. «'., the absence of blood-vessels.

Formation of Ci/sts. Pathologists hold widely ditTering views regarding the
origin of cysts. Some claim that cysts arise from the distended capsules,
entirely overlooking the fact that cysts are not infrequently found at the
periphery of the kidney, where there are no tufts. Others believe that cysts
start in an expanded tubule, without attempting to explain the process by
which the tubule attains the size of a cyst.

I have frequently observed tufts which were considerably reduced in size,
while the si>ace between them and the wall of the capsule was filled with a
finely granular mass, evidently sero-albnminous in nature. The capsule was
in no instance markedly distended, its diameter not noticeably exceeding that
of the normal capsular space. Probably such a condition arose from a chok-
ing of the uriniferoiis tubule, followed by a damming back into the capsule of

Fig. 352.-

- Compressed Tuft ix a Capsule, filled with Sero-
ALBUMixous Liquid. "Cirrhotic Kidney.

T, compressed tuft ; E, detaclicd epitlielia of the tuft ; A, tiiiely granular, sero-albumiuous
liquid ; C, capsule of tuft, uuchanged : O, interstitial, .slightlj- redeiuatous connective tissue.
Magnified ,500 diameters.

the liquid excreted by the tuft. In consequence of the pressure of the accu-
mulated liquid the tuft was compressed more and more, until finally its func-
tion was abolished. I doubt if we have any good reason for terming such
formations cysts. (See Fig. ?,ry2.)

A more satisfactory explanation of the production of cysts is the follow-
ing : The first thing noticed is an abimdaut formation of inflammatory cor-
puscles in circumscribed disti'icts of the kidney-tissue. These may be situated
in the cortex or in the pyramidal substance. Many of these corpuscles evi-

776

THE J'lUXARY TJiACT.

dently originated from tulmhir epithelia. The second stage is characterized
by the swelling of the inflammatory bodies, which afterward become pale,
and, by a process of liquefaction or mucoid degeneration, are transformed
into a hyaline, apparently structureless, mass. We very frequently find in
this mass delicate granular fibers, which resemble those of myxomatous tis-
sue. The new formation thus produced may, at the outset, be extremely
small and iiTegularly bounded by unchanged medullary coi-puscles. With
the growth of the cyst more medullary bodies gradually become liquefied,
till at length a cavity is established, containing a sero-albuminous fluid, and
bounded by flattened, polyhedral medullary corpuscles, which, in this
situation, might be designated endothelia. At the periphery a forma-
tion of fibrous basis-substance takes place, with the jiroduction of a cap-

FlG, 853.

■Cystic Degeneration of the Kidney in Chronic
Croupous Nephritis.

/, mass <»f iiirtaiiiiiiiitory coridiscles : M, striiifrs of a iiiyxoinatons connective tissue trav-
ersing cystic spaces, wliicli are filled with a sproallmniinous liquid ; C, fibrous connective
tissue iiroduciiifr the wall of tlie cysts. Maffnified (iOO diameters.

sule — the cyst-wall proper. Cysts, therefore, are the products of secondary
changes of medullary bodies which had their origin in kidney epithelia.
(See Fig. 35.3.)

Fatty Def/encrntioH. in all forms of chronic nephritis fat may appear in any
of the constituent tissues of the kidney ; more especially, however, in the
epithelia and in the interstitial connective tissue. Fat-gi-anules unquestion-
ably originate from particles of living matter, for in the epithelia we are
able to recognize theii- connection by delicate filaments with the bioplasson
reticulum.

Till-: I'uiSAin' TUAcr.

Ill

In the I'oinioctive tissue fat -{granules arc often observed in tlie hasis-Hub-
stiinee, thus provin^^ Muit the ))asis-substance is jxTvaded by livinj^ matter.
In hif^li (lefjre(>s of fatty nietanioi-jtliosis, whicli are observed in eirrhotic a»
wt'll as in atntphied iind iiypertroiiliie<l kidneys after ehronie croupous
nephritis, the fat-f^raindes eoalesee and form j^lobuies whieh to a {?reat
extent re])hie»' tlie epithelia of the tubules. Ijarge fat-{^U)bules are also
found in the intt>rstitial eonneetive tissue, whicli is under these circumstanceH
always increased in bulk. (See Fig. IJ;")!.)

Fatty easts, in all probability, orij^inate fi'om a disintef^-ation of the endo-
thelia, which had previously underejone a higli degree of fatty change. In the
same way can be explained the presence of the large amount of fat-gi-anules
and globules sometimes observed in the urine. This condition is always a
satisfactory proof that a high degree of fatty degeneration has taken place in
the kidneys.

Waxy Ih'(/e)uniti(ni. The epithelia of the tubules whicli have, in a measure,
escaped the inflammatory action, may become the seat of waxy degeneration,
when a similar condition has reached an advanced stage througliout the

Fig. 3."i4.

Fatty Degeneration of the Kidney in Chronic
Croupous Nephritis.

/,', tuhular uiiitliflia, containing: !iianules an<I f^lobule.s of fat ; /', fat-globule.s in tlie
widc'Ucil interstitial connc(:fiv(' tiMsiic : B, cai)illary blood- vcs.sel. .Maftiiitied t!00 diameters.

kidney-tissue. These epithelia sometimes assume the appearance of large,
glistening bodies projecting irregularly toward the center of the caliber of
the tube. When desquamated they are seen in the urine as more or less shin-
ing, homogeneous bodies, and readily recognized as waxy.

In chronic croupous nephritis, waxy casts are sometimes observed studded
with waxy epithelia, or with gi'anules, producing the epithelial or gi-anular
waxy casts. The formations of waxy easts in the tubides may l)e easily
traced from the epithelia, which are changed into waxy globules, in part
homogeneous and in part granular, and which by coalescence evidently form
waxy casts. Ai-ound these casts a wreath of endothelia, also in waxy degen-
eration, may be recognized. (See Fig. 3o.5.)

778

THE UlilNARY TBACT.

I have often found the connective tissue, both in chronic catarrhal and
in chronic croupous nephritis, the seat of waxy degeneration, l)ut, as before
stated, the highest degi"ees of tliis change are unquestionably observed in
chronic croupous nephritis. Simultaneously ,with the changes above
described, the walls of the blood-vessels in the connective tissue also under-
go waxy degeneration. I have occasionally seen specimens in which the
capillary coat was broadened and exhibited marked signs of waxy degenera-
tion, even before the arterial walls were affected. The more common oeciu'-
rence, however, is for the middle coat of the artery to give the first indica-
tions of the invasion of this metamorphosis, a characteristic which is the
rule in waxy degeneration of the spleen.

The tufts are also very frequently involved in the waxy metamorphosis,
and I have hardly seen a case of atrophy or cirrhosis without a waxy change

Fig. 355. — Waxy Degeneration of the Kidney in Chronic
Croupous Nephritis; Formation of a Waxy Cast.

W, shining, waxy liunps in tlie caliber of the tubule ; i, epithelia and endothelia of the
tubule, partly in waxj' change ; £, unchanged tubular epithelia; I, interstitial connective
tissue. Magnified (JOG diameters.

of the tufts more or less marked. The tuft may, at the same time, be con-
siderably enlarged, or it may show no increase in size. It is far more com-
mon, however, to find the tuft atrophied and solidified, the calibers of the
capillary vessels obliterated, when invaded by the waxy degeneration.

I have occasionally noticed in the veins, clots which were composed of
highly refracting globules, some of which exceeded the size of red blood-
corpuscles, each showing a central depression, and suggesting the idea that

////•; I in.\.ij:Y riricr. 77'.)

wavy ilogiMif ration of tlu» rt'd corpusolcs Inul tiikiui pliicT. In tlit^ coiint'i-tivc
tissue I have seen, tljough very rarely, clusters presentin{^ the appearance
above described, which, ])('rhii])s, mif^lit l)c coiisidcvcd waxy dcfjcneration of
extravasated blood.

In the course of iiiy rcscarclit's I sludicd sixteen kidneys, five of which
were affected with chronic catarriial nephritis, and eleven with chronic croup-
ous nejyhritis, and the conclusions arrived at were the foUowiiifj:

First. Clinniic cdtdnlidl iirjilirilis indinTsa new foniidtioii of en mice tire tis.siie
throittjhout the kiihwy, irliicli tissKc is fornird at flic r.r}>CNsr of the Kriiiiferoiis
tuhiiles. The siirfoce of the kidiieif is warked bi/ shnUoir ttejivessious, or hij t/roii-
iildtioiis, more or less iDiifoniilij distrihiited. Chniiiie etitorrhal ncphrilis inrorio-
hlij leads to a shrinkoi/e of the kidiieij — eirrhosis.

Seeoiid. Chronic croupous nephritis mail result in (itrojihij of circumscribed
portions of the kidneij, with more or less dcstrnction of the epithelial formations of
the affected parts. The surface of the kidneif shows deep retractions, between
which the cortical substance remains coniparatirelij nnchanijed. Chronic croupous
nephritis may also terminate in hypertrojihij of the kidney, with an increase of its
hulk. This increase is due to an aufpnentation of the interstitial conneetire tissue,
which, as a rule, is accompanied by a narrowimj of the tubules, tnid an almost
complete destruction and desejuamation of the epithelia.

Third. Suppurative nephritis may become chronic with an ene/ijisnlation of
the abscess, followed by a caseous metamorphosis of the pus.

Fourth. Cystic defeneration may occur botli in chronic ealarrlial and chronic
croupous nepliritis. Cy.sts are formed by a mucoid defeneration and litjuefaetion
of inflammatory corjjuscles which are the products of former epithelial bodies. In
the early stai/es of cyst-formation the cavity is traversed by myxomatous tissue and
irreyularly bounded by inflammatory corpuscles. In completed cysts a sero-
albuminous liquid is found, and the capsule is lined by a layer of flat endothelia.
Neither tlie capsule of the tuft nor the uriniferous tubules participate directly in
the formation of cysts.

Fifth. Fatty de</enerafion occurs both in chronic eatarrlial and chronic croujxms
nephritis, reachin;/ the liii/hest deijree, however, in the latter form of disease. It
consists of a transformation of bioplasson-ijranules into fat-granules both within
the epithelia and in the connective tissue. In high degrees of degenerative change
the fat-granules fu.'^e together and form globules, irhich are often arranged in
clusters.

Sixth. Waxy degeneration is a feature common to <dl forms <f chronic nephritis.
It invades the epithelia and ultimately produces waxy casts. In many instances,
connective tissue, capillaries, tufts, and arteries are all involved in the jtroce.ss.
Atrophied tufts are ahnost invariably the seat of waxy degeneration .

(2) The r((Iice.s, the peJrls., (itid the uyett'r are constructed after
the manner of all mucous membranes. The most internal layer
is fibrous connective tissue, covered bv stratified epithelia ; the
middle layers are composed of smooth muscle-fibers, and the
outermost layer is of loose, fibrous connective tissue. The mu-
cosa is made uj) of dense connective tissue, immediately below
the epithelial lining, and of delicate, loose connective tissue close
above the muscle-layers. The latter arrangement allows the for-

780

THE r'lx'IXAL'Y TliACT.

mation of lar^'e folds of tlic iinicosa, whicli occlude the cali})er of
all the above-nauu'd hollow fonuatious when at rest. The cover-
ing epithelium is stratified, and composed of a limited amount of
the columnar, cuboidal, and flat varieties, the latter having often
a caudate a])])earancc — /. c, supplied with a nuinher of offshoots
penetrating between the epithelia of the next deeper layer. Race-
mose, mucous glands are said to oc(air in the mucosa of the pel-
vis, but are absent from the mucosa of the ureter. (See Fig.
356.)

C T

Vui. ;J5('). — Calyx of the Kidney of a Dog.

A', stiiititicil ('iiitlifli;! ; ('T. coiiuectivo tissue. Ma.niiitied (JOO iliameters.

The muscle produces at least two layers — an inner longitu-
dinal, which is most developed, and an outer circular layer. The
circular muscle-fibers are the only ones remaining at the points
of attachment of the calj'x to the circumference of the papilla of

TllK riilSAIiY TliACT. 7Sl

the pyramidal siihstancc (Ilcnlc). Outside the <'ii-<Milar layer,
a<iaiii, a varyiiiii' inimlx'r of li)ii}^itudiiial hundlcs ai'c found, all
bt'injjf freely' coniu'cted with eneh other by ohiirinc liundles. and
havin<; marked septa of a fibrous perimysium.

(;{) The Kriiitiri/ hUuUhr is, in all essential })arts, identical with
the ureters; but its muscle-layers are very broad, and arranged
like a complex hurdle-work. The inner and outer layers take a pre-
vailin«>: loujifitudinal course ; the middle layers run mostly in a
circular dii-ection. The lon<iitudinal buiulles are more nuu'ked
in the main walls of the ])ladder, while the circular ftl)ers ])revail
at the place of transition into the ui'eters and the urethra, pro-
ducino; the internal sjdiiucter muscle. These fibers are also well
developed in the mucosa between the two orifices of the ureters
— the tri^t)num. The diameter of the walls of the })ladder varies
from two to fifteen mm., according to its conditions of contrac-
tion and extension. The arteries enter the posterior wall of the
bladder, and are traceable through the muscle-coat into the
mucous layer, where they break up into a rich capillai-y plexus.
The nerves are most numerous in the lowest portion of the lilad-
der — the so-called neck.

(4) The xrcflnui is a prolongation of the bladder, and presents
a structure similar to that of the bladder in the female ; while
the nuile urethra, being a canal common to the urinary and the
genital tract, is of a more complicated character.

The female urethra is lined with stratified epithelium ; its
mucosa liolds a few i-acemose mucous glands ; its muscle-layers
consist of an inner longitudinal and an outer circular — the smooth
fibers of the latter blending, at the periphery of the urethra, with
the striated muscle-fibers.

The male urethra has a stratified epithelium. It is maintained
by some authors that, in the whole cavernous and in a large part
of the membranous portion, there is but one layer of columnar
epithelia. As to the different portions of the urethra, the nature
of the covering epithelium requires more exact studies than have
yet l)een nuide up to the present time, and it is (juite possible
that there are individual as well as local differences. The epithe-
lial prolongations, in the form of racemose mucous glands (so-
called Littre's glands), are quite numerous along the mucosa of
the urethra, more particularly along the posterior wall. These
often exhibit very long and winding ducts, and but few acini ;
the ducts sometimes open into larger, funnel-shaped pits at the
inner surface of the mucosa. The muscle-layer is double along

782 THE UlilNAliY TliACT.

the urethra, the circular layer bein<j uiost marked in the mem-
branous poi'tion, and freely connectinj^ with the striped miiscles
which surround this part. In the prostatic portion the longitu-
dinal fibers are more develo])ed — especially, it is maintained, in the
regi(m of the colliculus seminalis. The cavernous i)ortion has a
limited amount of long-itudinal and circular bundles of muscle-
fibers. The veins of the urethra, according to Henle and C.
Lang-er, produce a plexus in the submucous layer, which is very
large, especially in the prostatic and meml)ranous portions, and
is distinctly marked, also, in the cavernous portion from the cav-
ernous body of the urethra proper. The latter is composed of
comparatively narrow venous spaces, inclosed by trabeculaa of a
fibrous connective tissue, which hold numerous small bundles of
smooth muscle-fibers. At the periphery the cavernous body is
insheathed by a layer of very dense, fibrous connective tissue —
the tunica albuginea — which is also provided with bundles of
smooth muscle-fibers, being mostly circular, and connected with
those of the trabecular of the cavernous body.

XX.

THE URINE.

MANY hundred microscopic examinations of urine, made by
the authority of the attending physicians of the patients,
and further corroborated by post-mortem examinations, have
enabled me to reach a certain degree of positiveness in the diag-
nosis of the diseases of the genito-urinary tract. As perfection
in any department is reached only after a great deal of practice,
the microscopic analysis of the urine also requires a thorough
study, which, however, is greatly facilitated by the guidance of a
reliable and experienced teacher.

I have published a part of the results of my examinations of
the urine with the microscope, in previous years.* In my con-
viction, it is in vain to study the sediments of urine without a
thorough knowledge of the minute anatomy of the kidneys,
and in vain will any one endeavor to understand the kidneys
without being thoroughly acquainted with their constituent
tissues — connective tissue, blood-vessels, nerves, epithelia. The
knowledge of the structure of the kidney involves the knowledge
of the whole histology.

Normal Urine. Normal urine is a yellowish, transparent liq-
uid, of a peculiar odor, slightly acid, neutral, or slightly alkaline.
The reaction depends greatly upon the food or medicines taken,

* "The Aid which Medical Diagnosis receives from Recent Discoveries in
Microscopy." Jrdiires o/ Medicine, February, 1879. "Diagnosis of Vagi-
nitis and Metritis, by Microscopic Examination of Urine." " Transact, of the
New- York Patholog. Society." The Medival Record, July, ISSO.

784 THE miNK.

and it is one of the many physiolo^rical puzzles why the kidnej'
epithelia produce, from the alkaline l)lood, acid urine. The spe-
cific j^T-avity varies between l.Olo and 1.022, which depends
entirely upon the amount of liquid taken into the body and the
nature of the food. The average amount, in twenty-four hours,
is looO c. c. — the solid ingredients representing sixty to seventy
grammes (925 to 1080 grains).

The organic constituents of the normal urine, held in solution,
are urea, uric acid, oxalic acid (bound to lime), hippuric acid, lac-
tic acid, creatinine — the so-called extractive and coloring matters
(xanthine, indican) — and, according to Briicke, grape-sugar. The
inorganic constituents are chloride of sodiiun, phosphate of soda,
magnesia, and calcaria ; sulphates of alkalies and ammonia salts
(in the coloring matters). The gaseous constituents are carbonic
acid, nitrogen, and oxygen.

Normal urine is of watery consistence, foaming, if shaken,
though the foam soon disappears when at rest. Sometimes the
urine gives out a repulsive odor after standing for a short time ;
it has a pleasant violet scent after the inhalations of turpentine,
and a highly unpleasant odor after the eating of asparagus.

If left at rest, normal urine exhibits a slight, cloudy sediment
— more marked, as a general thing, in the urine of WTjmen. This
consists of mucus, a few flat epithelia from the bladder or the
vagina, and mucous corpuscles, which appear as finely granular
(hydropic or swelled) plastids in a small numl)er. This sediment
commingles easily with the urine upon slightly shaking it. After
sexual intercourse, both the male and female urine — the male,
also, after a '^ wet di'eam " — contain large numbers of spermato-
zoids. Female lu-ine, at the time of menstruation, contains a
large amount of blood-corpuscles. As a matter of course, these
constituents have no pathological significance.

After standing for one or more days, fungi appear in the
urine. The rapidity of their development depends iipon the
height of the temperature of the surrounding medium. In acid
urine, especially oidium, the seed of mildew and afterward the
mycelium of mildew, leptothrix, and bacteria, are found, which
under these conditions grow very large, and, as a rule, are mo-
tionless or moving slowly. Oidium varies in size from a small,
homogeneous granule of high refracting power, to a globu-
lar or ovoid body, surpassing in diameter considerably that of
red blood-corpuscles. So far as I have seen, we have no reason
to discriminate between ''yeast-plant" (Saccharomyces urinap

////•; iKiXK. 785

I'cn'visiii', lactis, t'tc) and "oVdiiiiM," foi- tlicy arc identical in all
essential t'catni-es, as demonstrated by W, Hassloch (see page 40).
Alkaline nrinc, or an originally acid nrinc \vhi(rh lias l)c(;onie
alkaline, under the abovc-naincd conditions develops niiero-
«occi, baeteria, and lej)totlirix, which are smaller and in more
active motion the more alkalescent the urine becomes. Alkaline
urine sometimes holds the so-calle<l sarcina form, consisting of
small granules groujx'd in rectangular liiu's; this is kindred to
oidium, and probably but one of the; varieties in whi(;h mildew
appears.

P(if}i(>l(>f/ic((I Urine. In pathological conditions the urine may
be passed as a cloudy liquid of a consisten<.*e more or less deviat-
ing from that of water. The highest degrees of inspissation are
reached in chronic cystitis, when the urine, being highly alkaline
and decomposing in the bladder, appears as a viscid, stringy,
muco-purulent mass, in which are found large quantities of pus-
corpuscles and phosphates, has a repulsive ammoniacal smell,
and exhibits varying numbers of clustered micrococci ; a high
degree of color is reached, without an increase of consistency,
when biliary matters are present in the urine. Both color and
consistency are considerably augmented when the urine is mixed
with blood.

A highhi acid reaction is due to the presence of a pathologi-
cal amount of urea and urate of soda, in fever urine ; also to a
red extractive matter (uro-erythrine). In many instances, espe-
cially after abundant meat-eating and after intense bodily strain,
and in slight disturbances, such as catarrhal inflammation of the
mucosa of the respiratory tract, the mucosa of the stomach, and
that of the intestine, in diarrhoea, the lu'ine may be found laden
with uric acid and urate of soda, which under such circumstances
does not indicate a serious pathological condition. Women, in the
disturbances preceding menstruation, often void highly acid
urine. This, upon passing through the urethra, produces a slight,
bui-ning sensation in the mucosa.

Highly alkaline urine is voided by persons suffering from
chronic cystitis, from chronic inflammation in any part of the
body, especially in later stages of chi-onic encephalitis and
myelitis. A transient, highly alkaline condition has no patholo-
gical significance ; but if this condition is lasting, it points to
some serious ailment in the organism. I have several times
observed highly alkaline urine, laden mth phosphates, as a symp-
tom preceding nephritis.
.lO

786 THE URINE.

The aitioKiif of the urine is gi-eater the more liquid is taken into the body :
Lager-beer, for instance, yields excellent diuretic results. Necessarily such
watery lu-iue has a very low specific gravity. It is maintained that by profuse
drinking of water also the sum total of the excreted salts is increased, and
''hydropathic doctors" attribute their success in curing all sorts of diseases
to the "washing out" of the body, especially of the kidneys. Bodily exer-
cise — for instance, g^-mnastics — increases the quantity of the excreted salts,
without any increase of the watery constituents of the urine. A great quan-
tity of a watery urine is voided in cold weather, when the perspiratory
secretion is reduced or suspended ; furthermore, certain alkaloids, such as
those of laudanum, of coffee, tea, etc., stimulate the secretion of mine.
Nervous excitement, anxiety, fear, hard mental work, sexual excitement,
hysteric " fits," etc., produce the same effect. A very "nervous man" told
me that he had to micturate quite frequently whenever he was about to
write a " serious letter."

The amount of urine is, though not constantly, increased in
diabetes ; the color of diabetic urine is straw-yellow, its specific
gravity reaches the highest point — /. e., 1.040; and so does the
amount of the solid constituents, grape-sugar sometimes reach-
ing two hundred grammes in twenty-four hours.

The amount is considerably increased with a decrease of the
solid constituents in cirrhosis of the kidneys. One of the most
important clinical featiu'es of this disease is the constant voiding
of large quantities of a watery, nearly colorless urine, almost
completely destitute of salts.

The amount of urine is considerably reduced in intense
bodily strain, accompanied by free perspiration, often notwith-
standing profuse drinking, and in the beginning and acme of all
acute inflammatory diseases of the organs.

Fafhological constituents of the urine, variously combined
with normal constituents, are, besides the before-mentioned
grape-sugar and l)iliary matters, the follomng : albumen ; the
epithelia of the bladder in large quantities, and epithelia of the
prostate, the pelves of the kidneys, and the kidneys ; in the
female, besides epithelia of the vagina in larger quantities, those
from the cervical portion of the utervis and from the mucosa of
the uterus. Fvirthermore, blood, if not due to menstruation ;
pus-corpuscles, leucine and tyrosine and cystine, oxalate and
carbonate of lime in larger quantities ; fat-granules and fat-glob-
ules, tubular casts, and shreds of connective tissue.

Albumen is not always a pathological feature, since there
are persons who, after heavy meals, void small amounts of
albumen without exhibiting any symptoms of kidney disease. It

77//'; riiiXE. 787

iiivnriMltly nccoinpanics tlic severe forms of iie])liritis, juid liir{]^er
([Uiuitities of pus and ])loo(l in the urine. Ali)unu'n, on the eou-
trary, nuiy be absent in <ii-a\'e (^ases of catarrhal nephritis and
cirrhosis of the kidneys. In very ran; (*ases of so-caHed cdiyluria,
ch)udy urine is secreted of a liigli specific gravity, so rich in
albumen that it coagulates into a thick jelly upon being boiled.
In addition to the all)umen, which is always held in solution,
unless acids be added or the urine boiled, numerous fat-gi'anules
are present in chyluria, which render the freshly passed urine
opalescent. Lastly, a small number of plastids, of the aspect of
Ijinph-corpusdes, may be found. The disease in most cases
terminat(^s fatally, and tlie kidneys, it is maintained by good
pathologists, are found normal.

DefcrDiination of the Specific (iravity. According to Hofmann and Ultzmann,
we ascertain the exact specific gravity by means of the urinometer, as fol-
lows : Fill a standing glass cylinder four-fifths full of urine. The fi-oth being
removed by filtering-paper, the urinometer is placed in the urine, never being
allowed to come in contact with the walls of the vessel. Bring the eye on a
level with the surface of the urine, and read the corresponding division of the
urinometer, but not the upper rim of the fluid raised a little by attraction.
Toixch the stem, causing the urinometer to sink slightly in the fluid, and,
after it has come to rest, read again. In all such observations the urine
should have a temperature of at least G2o F. (17° C); otherwise consid-
erable eiTor may result. If the amount of urine is small, tlilute with even
three or four volumes of water ; test as directed, and multiply the number of
the division mark by the number of volumes used for dilution. For example,
if three volumes of water be added to one volume of urine, and we read
1.008, to obtain the real specific gi'a%dty of the original fluid 1.008 is
multiplied by l-fo = -t (1.008 X-4 = 1.032). The solid materials, on which
the specific gi-avity depends, which were dissolved in one volume, are, after
the dilution, dissolved in four volumes ; the specific gravity is therefore only
one-fourth of that of the original. By multiplying the decimal of the specific
gravity by the coefficient of Hiiser (2.33) we have the result in grammes of
the weight of solids contained in 1000 c. c. of urine. Hence, if we have the
entire amouiit passed in twenty-four hours, we can easily estimate the weight
of solids of the whole. For example, we have 1500 c. c. passed in twenty-
four hours, of specific gravity 1.020; to estimate the weight of solids in
1000 c. c.we multiply the decimal 20 — the last two figures — by the coeflfi-
cient 2.33 (20X2.33 = 40.(10), and the product, 40.(30, is the weight in
grammes of the solids in 1000 c. e. of the urine. Valuable conclusions may
be drawn from the amount of solids and the specific gi'avity ; but each case
requires special consideration. For example, we may have to deal with dis-
eased kidneys, the amount of urine being normal or diminished, of a low
specific gravity. We may conclude, since m-ea eomjjoses nearly the half of
the solid constituents, that urea has not been excreted in a sufficient quan-
tity, and we may consequently expect uraemia very soon.

788 THE I'BIXE.

Chemica! Tests. For practical i)urp()ses the clicmieal examina-
tiou of the iiriue is very siTiiple. Quantitative analysis is of com-
paratively small value, as all ingredients of the urine, at least
after it lias stood for a, day or two, become visil^le with the
microscope, and the amount of Krea, which, as such, cannot be
seen under the microscope, is in a constant proportion to the ui'ic
acid and its salts. It forms at least the half of all the organic
constituents.

The urine, as brought for examination, is either transparent
or cloudy. After the sediment has been deposited, we pour a small
portion from the upper parts of the liquid into a test-tube, im-
material what reaction the urine may give, and boil it over a
spirit-lamp. The results are as follows :

fa J The urine is transparent, and by being boiled remains
unchanged ; if a small sediment is present in the original fluid,
this feature indicates normal urine.

f]>) The urine is transparent, but after boiling becomes
cloudy. By adding a few drops of acetic acid, the urine clears up,
and this shows an increased amount of phosphates ; if efferves-
cence occurs upon the addition of the acid, carbonate of lime or
carbonate of ammonia is present. If the cloudiness remains after
the addition of the acid, we know that albumen is present, and, if
in large quantities, the urine is converted into a consistent, jelly-
like mass, easily spattering during the process of boiling. From
the sediment of the acidulated urine collected at the bottom of
the test-tube, an approximative estimation of the amount of albu-
men may be made.

fcj The urine is cloudy, and by being boiled clears up entirely.
This means an excess of the urates, especially of the urate of
soda.

fdj The urine is cloudy and remains so after boiling, or
increases in cloudiness. The same process nuist be resorted to
as in case fcJ, with the same diagnosis.

fej The urine is cloudy and remains unchanged by boiling
and by addition of acetic acid. This proves the presence of a large
amount of the organisms of decomposition, micrococci, bacteria,
and leptothrix in alkaline urine, and oidium or fully developed
mildew in acid urine.

An important chemical test is that for grape-sugar. Suspicion
arises of its presence, when for some time a large quantity of a
straw-yellow colored urine of a high specific gravity is passed.
Small quantities of grape-sugar may be present temporarily and

////•; ih-iM-:. 789

witliout iiiiy of tlic iianiccl fcuturcs. This form of diubctes lias
no clinical sii>iiilican(*c'. Not any of the tests for snj^ar taken
aloni' are entirely reliable, and for a thorouj^h deterniination of
its ]»rcsen<'e sevei-al mctliods must be resorted to.

Jrsts fur Siii/tir. (<i) Moon's J'ist. I'oiir into a ti'st-tubc two volumes of
urine and one volume of hydrate of potassa, and heat to boiling. Phosphates,
if precipitated in a lar-^er ((uantity, must l)e filtered off. Wlien the fluid
heeonu's hot, iiccordlMfj to the amount of sugai- jiresent, a lemon-yellow, a
yellowish-brown, or a blackish-brown color appears. By addition of a few
drops of nitric acid tlie licpiid loses its dai'k color and gives out an odor like
molasses. The additionof KOH to (told urine may produc<> a dark color, which
is due to the presence of coloring matters of the Itiie.

(h) Jioftj/o-'.s Test. Pour into a test-tube two volumes of urine and one
volume of KOH ; add subnitrate of bismuth in a quantity held by the point
of a i>en-knife and heat for a sliort time. If sugar is present, it reduces the
bismuth salts to the l)lack suboxide of bismuth. Small (piantities of sugar
will rentier the bismuth salts slightly giay. Albumen must be eliminated by
boiling and filtration, if present in larger quantities.

(c) Tronniirr's Test. Pour two volumes of urine into a test-tube, and add
one volume of KOH or NaOH (solution 1:3); add, drop by drop, a solntion
of sulpliate of copper (solution 1 : 10), and shake until the mixture shows a
blue color. Heat the mixture, without boiling : if sugar is present, the
copper-salt is reduced in such a way that at first yellow exiprous hydroxide,
and afterward a red sediment of cuprous oxide is formed. Albumen, if
present in large quantities, must be removed fii-st by coagidation and after-
ward by filtration. The yellow color of the mixture alone indicates either a
small (juantity of sugar or an excess of ui-ates. Mucus in large quantities
also i-educes the sulphate of copper in the same manner as sugar. K no
sugar is present, the mixture assuTues a dirty grayish-green, and no red pre-
cipitate appears at the bottom.

(<1) An approximate estimation of the amount of sugar present, which is
not admissible by simply considering the specific gi-avity, may be made by
the method of Vogel of boiling two volumes of urine with one volume of
KOH. A one per cent, solution of sugar assumes a canary-yellow ; a two
per cent, solution a dark amber ; a five per cent, solution a brown-red color,
the liquid remaining transparent ; while a t<m per cent, sobition is rendered
dark brown and opaque.

(e) liohoriti' Fcniioifatioii Tent. Into each of two bottles — one of four
ounces, the other of twelve ounces capacity — four ounces of the urine are
poured. A piece of- fresh yeast, the size of a walnut, is added to the lU'ine
in the larger bottle, wiiich is closed with a cork nicked for the escape of gas
evolved by fermentation. The smaller bottle is tightly corked, and the two
bottles are placed side by side in a uniform temperatiu-e of (38° to 75° F.
At the end of twenty-four hours the subsidence and clearing ofl^ of the scum
from the lu-ine in the larger bottle will annouuee the completion of the fer-
mentation. The specific gravity of each specimen is carefully taken by an
accurate urinometer, when any difference of specific gravity will indicate
sugar, and the number of degrees of difference the number of grains per fluid
ounce. For example, if the specific gravity of the unfermented urine is

790 THE UlilXE.

1032, and that of the fermented urine 1020, the urine contains twelve
grains of sugar to the fluid ounce. This test, although not accurate to the
smallest fraction of a grain, is clinically all that is needed for ordinary quan-
titative work.

(f) FeMhu/s tiiethofl is the most reliable for volumetric determination of
the amount of sugar. Fehling's solution contains in a volume of 1000 c. c.
the following: r{0.(j39 grammes of cupric sulphate, 173 grammes of pure
crystalline tartrate of sodium and potassium, and .500 grammes of a solution
of caustic soda of specific gra\-ity 1.12. Of this solution 1 0 c. c. are reduced
by 0.0.5 gi-amme of sugar.

Microscopic Examination. The urine, in an amount of four
to six ounces, is left at rest for at least six hours — still better for
twelve hours — either in an ordinary bottle of white glass, or in a
funnel-shaped ehampagne-glass. The sediment formed at the
bottom of the vessel is the subject for microscopic analysis, after
the transparent portion has been carefully decanted. We trans-
fer a droplet to the slide by means of a camel-hair brush or a
pipette ; the former answers all purposes if it is cleansed thor-
oughly with water after each examination. To preserve urine,
we use either simple glycerine mixed with the sediment, and left
at rest in a broad, open vessel until the surplus water has evap-
orated ; or a small amount of alcohol can be added before the
admixture of glycerine. Pus-corpuscles, epithelia, and casts are
best preserved by adding to the whole amount of ui'ine a few
drops of chromic acid solution, enough to precipitate the albu-
men and the other constituents. After several weeks the liquid
may be decanted and a few drops of alcohol added to the sedi-
ment, to prevent the growth of mildew.

Before entering the study of urine, the extraneous matters must
be well known. In Fig. 357 the most common are illustrated.

Silk-fibers are homogeneous, moderately shining ; their cut
ends are flattened by the blades of the .scissors, and rendered
slightly jagged. If woven, the single fibers assume wavy or
spiral impressions from their neighbors, and under these con-
ditions are also flattened.

Linen-fihers are composed of smaller fibrillae and show trans-
verse fractures or breaches, caused by the process of hatcheling.
The finest fil^rillae are broken off irregularly from the surface of
the main fiber.

Cotton-fihers are flat, wavy, and twisted, and are more com-
pact along the edges than in the center; the central portion may
show irregular breaches, or it rnay be absent if the compact
edges are pressed together.

THE VRINE.

791

Wool-lihrrs have serrated eilg:es, corrospondinf? to the cdfje
of the <'(ivt'riiii;- iinhrieatcd seah>s of tlie cutiele; the structure is
faintly striated. Hairs of dim'rent animals have different forms;
the et'ntral medullary canal as well as a varying amount of pig-

FiG. 357.— Accidental Occurrences in the Sediment of Urine.

S silk fibers; C, cotton fibers; i, liuen fibers ; U", sheep's wool; F, feather: St, starch-
jrranules of rice; Or, cork-particles ; O, ouUum, the see.l of mildew ; 3/, mycelium of mildew ;
"mc, micrococci ; B, bacteria ; Lt, leptothrix. Magnified 500 diameters.

ment, may be observed. If the cuticle is removed from sheep's
wool, it is termed shoddy.

792 THE UEINE.

Any of the above-named fibers may be fonnd dyed in differ-
ent colors.

Feather appears in single barbules, or in the shape of branch-
ing formations ; the ends of the barbnles are whip-like, the size
of the links gradually decreasing toward the terminations. Scales
from the wings of insects are also found ; these are delicate, ser-
rated plates, wdth a stem-like projection.

Of I'pfjefdhle matters the most common are oi'dium and myce-
lium of mildew, bits of cork, charcoal particles, poUen of plants,
mostly the seed of lycopodium (globular formations with a dis-
tinct shell, studded with thorny projections), and particles of
wood. Starch- granides are very common in female urine, being
used for powdering the genitals. In acid urine, motionless lep-
tothrix and bacteria are found ; in alkalme urine, micrococci,
bacteria, and leptothrix in active motion.

It must be knowu that flaws, which often present the shape of butterflies'
wiugs, scratches of the covering-glass, rust -particles in both the cover and
the slide, often occur. A physician brought me a specimen of a worm-shaped
mass of rust in the cover, which he mistook for an unknown parasite. He
claimed having seen the parasite quite often, and I discovered that he had
used the same cover for examination of the urine of a patient.

Grt/stalJine Pediments. The crystalline formations tV)und in
urine belong either to the group of acids and acid-salts, or to the
groups of alkaline salts. The acid sediments are uric acid, oxalate
of lime, urate of soda (amorphous), and hippuric acid. The fii-st
three are very common sediments, while hippuric acid is rare.
Still rarer are cystine and tyrosine, which also belong to this
group. The alTxaline sedimeuts are urate of ammonia, triple phos-
phates, calcium phosphates (which appear both as amorphous and
crystalline sediment), and calcium carbonate (amorjihous and
crystalline). Magnesium phosphate is exceptional.

(1) Uric acid is a constant ingredient of the urine of carniv-
ora. Its amount is greatly augmented by i-ich animal and veg-
etable food, by acute febrile diseases, by impeded function of the
heart, the lungs, the kidneys, the diaphragm, etc. It is decreased
in profuse secretion of lu'ine, and in the later stages of nephritis,
when the secretion of all salts is interfered with. It is also
increased by T)odily exei'cise. Its amount varies greatly at differ-
ent times in the urine of the same person.

Uric acid appears in lozenge-shape (rhomboidal prisms), with
numerous variations, and has always a broAvn or red-brown coloi-.

'////•; I'lnxK.

70:{

exc*q)t when ])n'('ii)itat<'d in very tliiii ])lat{'s. It is often col-
lected in star-shaj)ed ^rou})s of varvinj^ sizes, aud produces the
so-called brick-dust sedinu-nt. In super-acid urine, which is

Fig. :{5S. — Uric Acid.

C coiuniou crystals ; f, crystals from ovcr-acul urine ; ^'2, clusters (jfravel) of uric acid
from the pelvis of tlic kidney. Mafn'itifi'l -^OO diameters.

often conibiued with gouty and arthiitic processes, or with the
formation of ui"ic acid concretions in the bladder, it appears in
peculiar spear-, ('onib-, aud brush-shapes. The
concretions originating; in the pelves of the kid-
neys (so-called uric acid gi"avel) are comparatively
large masses, composed of minute cry.^tals of uric
acid. (See Fig. 358.)

(2) Oxalate of lime is frequently mixed with
uric acid, aud, if present in small quantities, has
no pronounced significance. Oxalic acid, being
a product of uric acid, has a special affinity for
calcium, and appears in the sediment — often very
late and only in the shape of oxalate of lime. In
derangements of digestion (dyspepsia) and dis-
turbances of the nervous system (" nervousness,''
'• neurasthenia,'' etc.) its amount is greatly aug-
mented. It appears in the form of (juadi'Llateral alate op Lime
octahedi'ous, with the characteristic letter-envel-
ope-like line in front view, while in edge view
the octahedral form is most marked. The refract-
ing power of these crystals is very high, and they
are without color. Theii- size varies from the smallest dot-like
squares up to crystals of quite considerable size, which, however,

Fig. 359.— Ox-

<J. ordinary crys-
tals of varying sizes;
Oi, rare forms. Mag-
nified 300 diame-
ters.

794

THE URINE.

are usually smaller thau those of lu-ie acid. Sometimes twin
formations of octahedrons are observed. Verj' rarely it appears
in the shape of concentrically striated disks or of dumb-bells.
(See Fig. 359.)

(3) Urate of soda appears in larger quantities under the same
conditions as uric acid, with which it is combined, especially in
febrile conditions. This salt produces the very common so-called
clay-water sediment. It presents fine, amorphous granules of a
dark brown color (very rarely colorless, and resembling coagu-
lated albumen), in a moss-like arrangement. It adheres easily
to foreign bodies (fibers) present in the vessel, and also to mucus
and epithelia. When the urine after standing becomes alkaline,

&^--.-^>s^ .

Fig. 360.—
Urate of Soda.

f>, orrtinai-y form ;
S', rare fomi ; .S'2,
forms of transition
of urate of soila into
urate of ammonia.
Magnified 300 diam-
eters.

Fig. 361.-

Bare Sediments op Acid
Urixe.

7/, liippuric acid ; C, cystine ; L, leucine ; T,
tyrosine. Magnified 300 diameters.

the gi-anules appear in the shape of delicate dumb-bells and in-
crease in size, both features being characteristic of urate of am-
monia. Uric acid crystals, under the same conditions, break up
into clusters of brown globules, which for a while still retain
the original lozenge-shape. A rare form of urate of soda is that
of needles arranged like sheaves of wheat (Ultzmann). (See
Fig. 360.)

(4) Hippuric acid is of common occurrence in herbivorous
animals, especially in the urine of horses; while in the urine of

77/ A" riilNE.

79r)

man it is V(My rart', an<l mostly <)l)S('rv<'(l after administration
of benzoic acid j)i"e})arations, and sometimes also in diabetes.
(See Fig. 'MW).

('i/sliiif is a rare sediinciit, wliidi sometimes produces eoncretious in tlie
bladder; it consists of hexagonal, colorless plates, which in side view show
(one) perfect facet, and (two) imperfect neighborinj; edge-facets. It is readily
soluble in ammonia, which is one of the features distinguishing it from uric
acid. In certain families it is said to be of regular occurrence in the urine.
(See Fig. 3G1.)

Tyrosine appears in the form of needle-shaped crystals, grouped in clusters
or sheaves, crossing at various angles. It is usually accompanied with
h'ucin<; which resembles flat, colored drops of fat of a large size, with delicate
radiating and concentric striations, but is insoluble in ether. These rare
sediments are observed in cirrhosis and yellow atrophy of the liver, and in
cases of phosphorus-poisoning. (See Fig. 3() 1 .)

(5) Unite of ammonld is found in fresh urine only when
passed in a decomposed and markedly alkaline condition, such as
occurs in chronic catarrhal cystitis. In alkaline

•urine this is a very common sediment in con-
nection with triple and simple phosphates. It
appears as In-own globules of var^'ing sizes,
exlii])iting faint concentric and radiating stria-
tions. The globules may appear single or in
clusters of several coalesced spheres, either
smooth or provided with th(jrny, sometimes
branching and curved offshoots — the so-caUed
thorn-apple shape. (See Fig. 362.)

(6) Triph phosphates (combined ammonium
and magnesium phosphates) appear as colorless,
highly refracting, rhomboidal crystals, varying
greatly in size. If incompletely developed, they
represent thin plates or cross-like formations
without facets. In normal urine they are found Dark brown Kiobuies.
only in small quantity, but are considerably Maffuined 3oo diame.
increased in chrtmie inflammatory processes,

also in so-called rheumatic and arthritic diseases, and in osteitis.
They easily dissolve by the addition of an acid. (See Fig. 363.)

(7) Simple phosphates (calcium and magnesium phosphates)
appear in alkaline urine in the form of amorphous, highly refi'act-
ing granules, without color, and usually clustered together, occa-
sionally in a moss-like arrangement, or in the shape of rosettes,
composed of pointed spicula', the points of which are united at
the center of the rosette, while each spicula may have a uniform

Fig. 362.— Urate
OF Ammonia.

im

THE finXK.

diaiiu'tf^r or l)e broadened toward the perij)liei-y of the rosette.
All these foriuatious are highly refrac^ting and colorless. Their sig-
nificance is the same as that of triple phosphates. (See Fig. 364.)
(8) ('aJriidii rarhoiiaff is the most common sediment in the
urine of hei'l)ivoi-ous animals, and the turlndity of theii* urine is

due to its presence. In man
this salt is of infrequent oc-
currence — appearing, together
with the phosphates, in the
shape of fine gi-anules or dumb-
bells. It is observed, in com-
l)ination with magnesium salts,.
as delicate prisms. It appears
mainly in inflammatory and
(various processes of the bony
system. The addition of acid
produces an effervescence of
this salt, as well as of ammo-
nium carbonate. (See Fig. 864.)-

.Magnesium jiliosjihrtte is obsei'ved
ill urine after the internal use of the
fixed alkali-carbonates, such as are
held in solution by many mineral;
waters. It produces elongated quad-
rilateral plates.

MiifKs occurs in varying
(luantities in normal urine-
more especially in the female. It appears as finely striated,,
scarcely perceptible strings, being a physiological product of
the epithelia. Slight initation of the mucosa by acid urine
laden with uric acid and m-ate of soda, increases the amount
of mucus, and, the urates being precipitated on it, the sti-ingj-
masses become more easily perceptible. They may be mis-
taken for casts, as they Ijear some resemblance to them. Mucus-
corpuscles, together with mucus-sti-ings, are also obser^^ed,
ha\4ng the character of finely gi-anular, sometimes nucleated,,
plastids. If sperm is admixed with the urine, its mucous con-
stituent appears as pale, caky masses, entangled with spermato-
zoids. In chronic catarrhal inflammation of the mucosa of the
^u•ethra, the mucus-strings, voided fnmi the ducts of the mu-
cous glands, are very large, cylindrical, and twisted ; they often
are perceptible to the naked eye. The mucus secreted by the pros-

FiG. ;iO;j.— Triple Phosphates.

JP, perfectly <leveloi)efl crystals; /»', inijier-
fectly developeil crystals. Majmiticrt 300
diameters.

////•; I III St:.

71)7

tate ^hiiul (lui'in^ sexual cxcitcnu'iit contains numerous niuens-
eor})us(*les, which, when ()i-i«iinatin^ from the cf)lumnar e{)ithelia
of duets, are in part elonj;jite(l. Mucus a{)pears also as delicate,
striated, and frin«>;y cylinders, the so-called " nnu^ous easts;'' it
is doubtful, however, whether they are ever produced in the
uriuiferous tuluiles.

Sometinu's j)ale concenti'ic foi'inations are fomid in the male
urine, which are so-<^alled colloid or oiui/loid rorpiisrhs of ihi'
pro.sfdfc (jlditd (])rostatic concre-
tions). Their numl)er seems to
be au<?niented nniinly in hyper-
trophy of this ^land.

Pns-rorpi(srl('s always indi-
cate an intianimation alon<>- the
genito-nrinary tract. Theii- ori-
gin was dwelt upon in the chap-
ter on '' inflammation " ; here I
wish merely to repeat that a
large number of pus-corpuscles
arise directly from the epithelia,
by endoji'enous new formation
of living matter. The pus-cor-
puscles are the best material for
determining the general con-
stitution of the patient, Ms
chances for recovery, or the
probable duration of his life

(see page 62, Fig. 20). The ^, amorplious simple pliospliates; .V, st-ir-

presence of pus-corpuscles of sl'apea simple phosphates ; C. amoiplums car-

^ _ ^ ... honate of lime ; M, combiuatlon of carbonate

the series P exclusively indi- of llme with inagneslum salts. Maguilieil 300

cates a broken-down coustitu- "*='"»•»*"'•«•

tion, and the rapidly approaching death of the patient. Pus-corpus-
cles in freshly passed urine exhibit active amoeboid form-changes,
which may be oliserved exceptionally, even twenty-foiu' hours
after the urine has been passed. Pus-corpuscles, with delicate,
hair-like prolongations (cilia), arise from the ciliated, columnar
epithelia of the uterus; in freshly passed iu*ine the cilia may show
wa\-ing motions. Care must be taken not to mistake the cilia
for bacteria adhering to the surface of the pus-corpuscles, and
also exhibitiug oscillatory movements.

In very dilute or highly alkaline urine, pus-corpuscles swell
and assume a large, globular shape, the central portion being

Fig

:'>V>4. — Simple Phosphates and
Carboxate of Lime.

798 THE IRIXE.

occupied by the nucleus, while the peripheral portions show
only a small number of {granules. In highly ammoniacal urine,
voided in chronic catarrhal cystitis, the pus-corpuscles, when
present in a large quantity, by bursting and coalescence produce
a sticky, slimy mass, which can be transferred to the slide only
in coherent, jelly-like lumps. Upon evaporation of the S})ecimen
of urine kept on the slide, the pus-corpuscles present variously
jagged forms, which should not be mistaken for the result of
amoeboid motion.

In chi'onic catarrlial cystitis, j>us-corpuscles from pigmented
epithelia of the bladder, to the presence of which is due the slate
color of the mucosa, also exhibit a varj'ing amount of dark
brown pigment-granules. Pigmented pus-coii:»uscles at once
justify' the diagnosis of chronic catarrhal cystitis.

Pus-coi-puscles which have arisen fcoxa. epithelia of the pelves
of the kidneys, or from those of the uriniferous tubules, some-
times contain delicate red T)rown crystals of haematoidin. This
indicates the presence of haematoidin in the epithelia, caused by
a previous haemorrhage. In recent haemorrhage the pus-cor-
puscles may have a uniform yellow color, due to imbibition of
the coloring matter of the blood.

Rad hlood-corpuHdes are discoid bodies of a yellowish luster,
in the fresh condition, and often crenated. After standing for
a few days, acid urine may have the same influence upon the
blood-corpuscles as dilute solutions of bichromate of potash
(see page 64), inasmuch as many Ijlood-coii^uscles appear gi-anu-
lar with low, and distinctly reticular with high powers. By the
addition of a solution of chromic acid the same result may be
obtained, though, as a nde, much less marked, and most of the
red blood-corpuscles after treatment with chromic acid appear as
pale, apparently structureless, double-contoured circles.

Extravasated ))lood, if retained within the tissiies, changes to
luenuitoiflin, which appears l)oth in the sha])e of minute, oblong
rhombs, and needle-shaped, sometimes stellate, crj-stals of a brill-
iant red-brown color. Such crj^stals may be observed, as before
mentioned, in the interior of pus-(;orpuscles. In a case of chronic
abscess of the kidney I have seen large quantities of haematoidin
admixed with the pus ; the chronic condition could be diagnosed
mainly from the presence of haematoidin.

Shreds of connedice tissue are of frequent occurrence in the
sediment of urine. They are seen either as delicate bundles or
as bulky shreds, containing, in the latter instance, a varying

Till-: rnixK. 79!>

miinlH'r of phistids (coniu'ctivc-tissuc coi-puscrk's). Tlieir preseiute
may be due to lueraorrliufre, and, in this instiinee, they as a rule
have a yellow tint fi-oni the colorini^ matter of the l)lood. Small
shreds of bundles of connective tissue of a yellow (!olor, if j)res-
ent with large (juantities of blood-corpuscles and kidney epithe-
lia, but without ])us-cor])uscles, indicate ca])illary luemori'liaj^es
in the kidney. Larg-e shreds are present whenever an abs(!ess
has emptied into the imuary tract, or ulceration has taken place
either in the urethra (in strictures), in the bladder, or in the pel-
ves of the kidneys. The aecomi)anying" epithelia enable us to
determine the seat of the ulceration. Ulcers of the va<^ina, the
cervical portion of the uterus, and its mucosa, may be diagnosed
by the same means. When a papilloma is developed in the
mucosa of the bladder, large shreds of connective tissue, contain-
ing blood-vessels in formation or fully developed, are exception-
ally voided with the urine. Occasionally these shreds assume the
shape of coils. (See Fig. 805.)

Shreds of connective tissue have a highei" refracting power than mucous
strings, but less than linen-fibers, and they cannot be mistaken for any of
these formations. I have observed a large number of regular linen-tibers
voided with the urine in a case in which external urethrotomy had some time
previously been performed, and the siu'geon had accidentally left a plug of
lint in the urethra, which probably had found its way into the bladder.

Fut-granules and fat-globules are of very common occurrence
in urine. The latter may be passed of quite a considerable size^
and that such globules are really formed in the kidneys can be
proved by direct observation (see page 777, Fig. 354). In many
instances, however, fat is extraneous, due to impurity of the ves-
sel or to the fat (oil, vaseline) used for lubrication of catheters
and sounds, or the finger used for exploration of the fenuile gen-
itals. Small fat-granules are invariably found accompanied by
albumen, and, after precipitation of the latter by an acid,
the bright, glistening granules of fat, clustered together and
varying in size, are easily distinguished from the albumen,
the granules of which are pale and of a uniform size. The pres-
ence of fat-granules indicates fatty degeneration of the kidneys,
and more certainly if fatty casts are also found. In this condi-
tion often a few red blood-corpuscles and shreds of connective
tissue are mixed with the sediment, caused, perhaps, by a certain
brittleuess of the walls of the capillaries. In chylous urine fat-
gi'anules are formed in connection with albumen, without any
kidney epithelia or pus-corpuscles. (See Fig. 365.)

800

THE rJilXE.

EpitheJid. An acquaintance with the epithelia found in urine
is of the greatest importance, since it is only by an accurate
knowledge of the point from wlience they come that we are
able to obtain a diagnosis of the location of the morbid process.
Most of the morbid processes occurring along the genito-urinary
tract are inflammatory in nature, and marked by the presence

Fig. 36."j. — Various Occurrences in the Sediment of Urine.

M, luucus-tli reads ; .S', sperniatozoiils : PC, i)rostatic concretions : P, ciliatiMl pus-corpuscles ;
P', pus-corpuscles, with pifrment-granules ; P^. pus-corpuscles, witli lia-matoidin-crystals ; B,
red blood-corpuscles; if, liaimatouUn-crystals ; ^.coagulated albumen; /', fat-granules ; C,
shreds of connective tissue ; C^, debris of papilloma of the bladder. Magnified 500 diameters.

of pus-corpuscles in the urine ; where the inflammation is lo-
cated can be determined oidy by the epithelia. Wlien pus-cor-
puscles are found unaccompanied by epithelia, which sometimes

THE rUISK. HOI

occurs, we ar<' imablc to decide where tlie rin»rl)id c<ni<lit ion is
situated.

As a general thinj^, we know that in the male genito-urinary
tract tlie ur«'tlira, the l»hulder, the ureters, aud the pelves of the
kidneys have a liuin^of stratified epitiielia ; while all glands in
connection with the tract, the mucous glands, the prostate, and
their ducts, including the ejaculatory ducts, have a single layer
of epithelia. A single layer is i)resent also througli(mt all the
ni"initei-ous tubules. The largest e])ithelia are found in the
urethra ; next in size are those of the bladder, then follow the
epithelia of the pelves of the kidneys, and the smallest epithelia
come from the kidneys proper. It is maintained that the epithelia
of the bladder, of the ureters, and of the pelves of the kidneys,
are identical in size and shape. By scraping off the epithelia of
the above-named organs, this idea appears correct ; but, if we
study the epithelia hi situ, we arrive at the conviction that the
epithelia, upon api)roaching the kidneys, very gradually decrease
in size from Avithout iuAvard. Middle-sized epithelia of the bladder
are identical with the largest pelvic epitheha, and, therefore, are
of no value for diagnosis, whi]e the average epithelia of the pelves
are distinctly smaller than those of the bladder. The candate,
double caudate, and lenticular forms of epithelia are far more
prevalent in the pelves and calices than in the bladder, and well
adapted, therefore, for a diagnosis of jiyelitis.

In the female genito-urinary tract, the epithelia of the vagina,
the cervical portion of the uterus, the urethra, bladder, ureters, and
pelves, are stratified. The epithelia of the mucosa of the uterus
are columnar and (dliated, forming a single layer ; the kidneys
also show columnar, flat, and cuboidal epithelia in a single layer,
the same as in the male. Flat and cuboidal epithelia of the
kidney, in the urine of either sex, cannot be distinguished, but
the columnar epithelia are distinctly marked formations. Besides,
in either sex, flat, homy epithelia from the fingers and the external
genitals may be found, having a jagged contour, a high refrac-
tion, a homogenei^us appearance, and no nucleus. They often
are studded with particles of dust or granules of fat. Epidermal
scales from the inner surface of the prepuce and that of the labia
majora are paler, and often hold granules of fat (sebaceous
material).

The diagnostic value of the epithelia in urine, if mingled
with pus-corpuscles, is as follows (see Fig. 366) :

Male Urine. The largest flat epithelia from the urethra are
51

802

THE URINE.

occasionally seen, /. e., in the initial stage of catarrlial or blen-
uorrhoic inflammation ; the largest columnar epithelia from the
m*ethra occur in deeply seated blennorrhoic inflammation and
in ulceration, %vhieh often lead to the formation of a stricture.

Fig. 366. — Epithelia Fouxd in Urine.

-B, bladiler-epithelia from iipper layers ; B^^, Ijladiler epithelia from middle layei's ; SD^
bladder epithelia from the deepest layer ; J", jirostatic epithelia ; J?, epitlielia from the
ejaciilatory ducts: T', vaginal epithelia from upper layers; VM. vaginal epithelia from
middle layers ; ^'D, vaginal epitlielia from the deepest layer ; C, epithelia of the cervix nteri ;
U, epithelia of the mucosa of the uterus: I'll, epithelia from pelvis of tlie kidney; KC.
kidney epithelia from the convoluted tubules ; K,S, kidney epithelia from the straight collect-
ing tubules. Magnified 500 diameters.

rill-: rinxi':. 803

Cuboidnl cpillu'lia, soiiicwliiit sinallcr than the uvcrafi^e
ciiboidal cpitliclia of the bladder, coiiic from the prostate in
catarrhal prostatitis and hy])ertrophy of the jn'ostate. Ciliated
cohiinnar epithelia. distinctly snr])assin<i: in size those from the
mucosa of the uterns, indicate slight catarrhal intlammation of
the ejacnlatory ducts. They are rarely seen ciliated, as the cilia
break off very easily; but delicate parallel rods in the interior
of the epithelia, near their l)asal surface, indicate that the
epithelia were originally ciliated.

Female Urine. The large, flat epithelia from the vagina are very
eommon occurrences, and indicate catarrhal vaginitis; they appear
singly or in clusters, and arc often studded with micrococci. The
largest culjoidal and columnar epithelia from the vagina are ob-
served in cases of intense, deeply seated, or ulcerative vaginitis.

Flat and cuboidal epithelia, smaller in size than those of the
vagina, and, as a rule, finely granular, often with offshoots, are
shed from the cervical portion of the uterus. If present with
pus- and blood-corpuscles and shreds of connective tissue, they
indicate ulceration of the cervix.

It must be borne in mind that cuboidal epithelia are originally angular,
polyhedral formations, but, b}^ swelling in the urine, assume a more or less
regular — nay, perfectly spherical, form. The size of the spheres, however^ is
sufficient for a diagnosis of their pre\'ious location. If destined for micros-
copic examination, care must be taken not to have male and female urine
mixed, which might easily happen in married life. On account of such a
mixture I once mistook the sex. In this case, besides vaginal epithelia,
starch-gi'anules were also present in large numbers. The gentleman denied
the use of powder, and his clean m'ine afterward settled the question.

I have seen prostatic (q>itfielia of the male, and cervical epithelia of the
female, of a higher refracting power, a nearly homogeneous, waxy look, with
an inilistinctly marked nucleus, in persons affected with sj-philis. In a nimi-
ber of cases, from these appearances I have correctly diagnosed s\iihilis ;
but my experience in this respect is too limited yet for announcing that the
waxy metamorphosis of the above-named epithelia is always due to sj'philis.
There may be other .chronic ailments of the system, or of the organs frooi
which the epithelia were cast off, producing the same appearance.

Delicate columnar, ciliated epithelia arise from the mucosa
of the uterus, and indicate catarrhal endometritis; these epi-
thelia are found accompanied by ciliated pus-corpuscles, which
arise from the epithelia. In freshly voided urine I have seen
the cilia of both these formations in waving motion.

Common to Both ibexes. Flat epithelia of the ^bladder, in
small numbers and without pus-corpuscles, are of normal occur-

804 THE UlilXE.

reiice in the urine. When present in a larger amount, together
with pus-corpuseles and epithelia of the middle layers, exhibiting
endogenous new formation of pus-corpuscles, they indicate acute
catarrhal cystitis. The flat epithelia of the bladder may be
found in clusters similar to those from the vagina ; their size,
however, is a sufficiently distinguishing feature. If the cuboidal
epithelia largely outnumber the flat, or are scanty in comparison
with the large amount of pus-corpuscles, the diagnosis of chronic
cystitis is justified, and with greater certainty if some pus-
corpuscles contain dark brown pigment-granules.

Caudate epithelia, somewhat smaller than those of the mid-
dle layers of the Ijladder. originate from the pelves of the kidneys.
They are sometimes combined with clusters of uric acid crystals,
which, when present in freshly passed urine, indicate their origin
in the pehis. Not infrequently these are accompanied by a large
number of red blood-corpuscles and shreds of connective tissue,
caused by haemorrhage and ulceration in the pelves. Pehic
epithelia are often found in connection with kidney ex)ithelia
(pyelo-nephritis).

Small r-uboidal and columnar ejjithelia are shed from the
lu-iniferous tubules of the kidneys. Thej* invariably indicate
catarrhal nephritis, when pus-coi-puscles are also present ; with
pus-corpuscles and tube-casts, they prove the presence of croup-
ous nephritis. "Without kidney epithelia in the ui'iue, nepkritis
cannot be diagno.sticated ; these and the tube-casts are the only
positive evidences of the presence of inflammation of the kid-
neys. In very acute nephritis, clusters — nay, cast-like tubes
of kidney epithelia, may be found in the urine.

TuhuJar Casts. The most characteristic sign of croupous
ne]jhritis is the presence of tube-casts in the urine, and in my
experience the casts are always indicative of the disease, and,
with gi-eater certainty, the larger the accompanying amount of
the albumen. Reliable observers have seen casts without any
albiunen in the urine, and it has been asserted that mere hyper-
a?mia of the kidneys may suffice to throw casts intc^ the urine,
without any evil consequences — for instance, after treatment
with large doses of iodide of potash. The former assertion I can
corroborate, the latter is not in concurrence with what I have
seen ; the casts surely indicate nephritis, and the greater their
number the more serious is the disease.

We disiinguish six varieties of tube-casts, ^-iz. : hyaline,
epithelial, blood, granular, fatty, and waxy casts. (See Figs. 367
and 368.) Their diagnostic value is as follows :

rill': iiiisH.

805

Tlit' /ii/ti/in(' and t'j)iflii'li((l casts — not the <l('S(iuainat<Ml epi-
thelial tubes, hut hyaline easts stu(hle(l with epitlielia — indicate
ueute croupous nephi-itis. They sonu'tiines have a yellow color,
and a slightly increased refracting power, owing to their iinhihi-
tion of the coloring matter of the blood.

The l)lo(i(Jr(tsfs show Ineinoi-rhage within tin- kidney; a hu'ger
iiunilier of such casts almost always foretells, moi-e certainly in

Fig. ;}(j7. — Varieties ok Casts ix Acute Croupous Nephritis.

The series a shows casts Iroin couvoliiteU tubules of the seconil onler; the'^iseries b, casts
from the narrow portiou of the looit-tubules ; the series c, casts from the straight collecting
tubules. //, hyaline casts ; J?, epithelial casts; J?, blood-casts. Magnified 500 rtlanieters.

adults than in children, fatal termination in a short period of
time. If blood-casts have })een retained in the tubules for some
time, the blood-corpuscles lose their shape, and the cast has the
appearance of a dark red-brown, granular cluster.

(ivdiudar, fatty j and waxy vasts appear in the protracted,

806

THE UlilNE.

chronic forms of croupous nephritis. The grannhir easts are
probably due to the disintegration of the kidney epithelia and
the lining endothelia ; they, however, are seen sometimes also in
acute croupous nephritis — especially in children after scarlet
fever and diphtheria. Fatty casts indicate fatty degeneration of
the kidneys, secondary to croui)()us nephritis. In all these

F

Fig. 3 6 S.— Varieties of Casts in Chronic Croupous Nephritis.

Tlie series a sliows casts from convoluted tubules of the second order; the series b, casts
from the narrow portion of the loop-tubules; the series c, casts from the straight collecting
tubiUes. G, granular casts ; F, fatty casts ; W, waxj' casts. Magnified 500 diameters.

instances the substance of the cast is the same, and only the
outer adhering formations give the difference in the appearance.
Waxy casts are different in their chemical nature from hyaline
casts, being characterized by a yellowish color, a great refracting
power, wavy or fluted outlines, and a high degi-ee of brittleness.

THE riilNE. 807

Such casts will not l)c seen — iiijainst tlic views of recent wi'iters
— unless waxyde^'eneration has been estahlished in the kidneys.

Sometimes hyaline and epithelial casts exhiliit spiral wind-
injifs, proba))ly from ha\'in<;- ori<^inated in the s|)iral portion of
the ascendinii' branch of the lo()p-tul)nle. They have no special
si<rnificaiice.

Besides, a g'reat projiiiostic value attaches to the size of the
casts. As a matter of course, easts formed in the convoluted
tul)ules of the first order will never appear in the urine, as they
cannot pass the narrow tul)ules. The mildest degrees of the dis-
ease are indicated by casts from the narrow tubules, the narrow-
est casts, and a small number of casts from the convoluted
tubules. Not infre({ueutly we meet with j)edunculated casts,
viz. : formations from the place of transition of the narrow
tubules into convoluted tubules of the second order. Casts from
the convoluted tubules justify the diagnosis of croupous nephri-
tis in the cortical substance ; casts of all the three sizes — the
largest arising from the straight collecting tubules — permit of a
conclusion of croupous nephritis in the whole organ, and upon
this condition a very unfavorable prognosis can be established.

Based on these simple facts, I was enabled to give a prognosis, even where
no danger was suspected by the attending physician. Dr. X., a prominent
practitioner, brought me some fresh ui-ine passed by his son, six years old,
who had just recovered from a slight diphtheritic attack of the throat. The
question was, wliether in the fresh urine there could be seen moving micro-
cocci and bacteria. I really found these low organisms, but, besides, also
numerous tube-casts of all the three sizes. I told the father that his son was
in danger. He laughed at me, and asserted that there was nothing from the
clinical stand-point to justify such an alarming diagnosis. This happened on
a Sunday, and I did not hear of the child until the next Wednesday, when I
was informed that the boy had died in an urjemic fit. The physician now
began to believe in microscopy, and a year afterward brought me some urine
of his wife, containing a moderate quantity of albumen. In this urine I found
fatty casts from the convoluted tubules, and, as the gentleman wanted to have
a prognosis, I told him that his wife could not live longer than one or two
years. In this ease I was mistaken, as three months afterward the lady was
carried away by ursemia.

Stress must be laid on the general constitution of the patient, such
as can be positively recognized by the appearance of the pus-corpuscles
present. We can tell how much the constitution had been lowered by the
disease, and, of course, the prognosis will be the more unfavorable the more
Uving matter the patient has lost — the worse, therefore, his constitution is at
the time of examination.

Dr. R. E. Swinburne, in 1878, examined, in my laboratory, lu-ine contain-
ing numerous casts, and both kidney epithelia and pus-corpuscles having very

808 THE IJIUNE.

little bioplasson, indicated a completely broken-down constitution. He diag-
nosed chronic croupous nephritis, and, when I inquired about the prognosis,
he said, '• The cofBn ought to be made for the man." The next day the physi-
cian came who had brought the urine for examination, and, when he learned
the diagnosis and prognosis, exclaimed, "Why, the man died last night;:
the coffin is being made for him."

Among the formations due to the presence of entozoa in the
genito-urinary tract deserve to be mentioned : hooMets of echino-
cocci, which, in rare cases, have been observed in the urine, indica-
tive of the presence, of ruptured sacs of the echinococcus in the
kidneys. Further, the ova of the distoma JicBmafobmm, or Bil-
Jiarzia ha'niafohia, which are oval formations with a distinct
shell and a short point at one pole. This entozoon lives in the
veins of the prostate and the bladder, and by rupture of the
vessels into the cavity of the bladder the ova are deposited in
the urine. The disease occurs in North Africa only, and more
especially in Egypt. I have, however, never seen formations of
this kind myself. The tnchonionas rayinalis, a ciliated animal-
cule living in the mucus of the vagina, is sometimes seen in the
urine. In a case that came under my observation, the physician
suspected an ascaris himbriroides in the bladder of a child — the
worm, as he supposed, havdng found its way through the urethra.
Besides symptoms of acute cystitis, numerous dark brown gran-
ules were observed under the microscope, which perhaps might
have been the fjvces of the worm. Further particulars of the
case were not known.

Diagnosis from Examination of Urine. Here I wish to briefly
describe what, from my own observations, I have found to be
correct. Whenever larger quantities of pus or blood are mixed
with the urine, albumen is also present, and an approximate
estimation must be made as to its amount, whether it is equal to
that of the pus or blood present, or whether it exceeds the
amount of the two latter. Expressions like '' false albuminuria,''
or '^pseudo-albuminuria," used for such cases, should be avoided,
as no proper significance is attached to these term's.

Urethritis may be diagnosticated in the initial stages by the
large amount of flat urethral epithelia ; in later stages the pus-
corpuscles are largely predominant, and cuboidal and columnar
epithelia may also be seen. If long mucous cylinders are present^
sometimes with knob-like terminations, which arise from the
mucous glands of the urethra, the diagnosis gleet is justified. If,
besides flat epithelia of the urethra, columnar epithelia, blood-

THE VlilM':. 809

(H)rpus('l('s, iiiid slircds of coniu'ctivc tissue! arc found, nherafioti
and stficfiirc may ))(' suspcctt'd, ujoiv iKirticulai'ly if, in additioit
to the above-named formaticnis, epithelia of the })n)state make
their ap])earan('e.

I'rosfafifis, ocM-urrinj^- in youn<>- men subject to intense sexual
exeitenuMit, and often mistaken for sperm atorrliani, may b<; diaj^-
nostieated by the presence of an increase of mucus, pus-cor-
pusck^s, and prostatic epithelia. After involuntary emissions of
semen, s])crmato/oids ar-c found in the urine. In all cases of so-
ealled spcrmatorrhn'a that have come under my ol)sci-vation,
prostatitis was found to exist. In one case, tlie urine that was
first ])assed from the urethra proved to l)e puruh'nt, while the
later portions were transparent ; and many of the pus-(;()rpusclei*
exhibited long* cilia, as if a spermatozoid had been transformed
into a pus-cor[)uscle. This feature rendered the diaj^nosis '^ sup-
purative intlannnation of one vesicula spermatica" hig'hly prob-
able, and was in accordance with the clinical facets. Prostatic epi-
thelia and prostatic concretions, tog-ether with the characteristics^
of cystitis, allow the conclusion of hypertrophy of the prostate.

V((f/iiiifis is characterized by the presence of numerous vaginal
epithelia, partly studded with micrococci and pus-corpuscles.
The large euboidal and columnar epithelia appear in the more
intense degrees of vaginitis, and a large number of connective-
tissue shreds are also found in ulcerative vaginitis. Mild forms
of vaginitis are observed in almost all women suffering from
endometritis, more particularly after the delivery of children.
Vaginal epithelia may be completely al)sent in the urine of small
girls and virgin matrons.

(Jerricifis may be diagnosticated by the presence of cervical
epithelia and pus-corpuscles ; ulcerative cervicitis is marked by
the shreds of connective tissue, in addition to the usual epithelia
and pus-corpuscles.

Endometritis shows in the urine ciliated columnar epithelia of
the mucosa of the uterus and ciliated pus-corpuscles arising from
them. Ulcerations are marked by the presence of shreds of con-
nective tissue and blood. How far the diagnosis of tumors of
the uterus is admissible from the examination of urine, I am
unable to tell from my own experience.

(Ji/sfitis may be recognized both in its acute and chronic
stages. In acute cystitis the urine may be acid, containing a
varying amount of pus-corpuscles and epithelia from upper and
middle layers of the bladder, the latter exhibiting the character-

810 THE URINE.

istic features of endoa:enons new formation of pus- corpuscles.
In subacute cystitis the features are similar. In chronie catarrhal
cystitis the flat epithelia of the bladder are usually absent, and
only those of the middle and deepest layer (cuboidal and colum-
nar) found. In chronic cystitis the pus-corpuscles sometimes
contain dark-l)rown granules of pig-nient. In the highest deg^-ees
of cystitis scarcely any epithelia are present, and only enormous
quantities of pus-corpuscles, mostly swelled, hydropic and disin-
tegrated, are to be seen. The urine being highly alkaline, the
purulent sediment produces a jelly-like, viscid mass, in which,
besides crystals of alkaline salts, clusters of micrococci are pres-
ent. The presence of blood-corpuscles and shreds of connect-
ive tissue, in addition to the other features, indicates ulcerative
cystitis. Large quantities of blood may entirely conceal the
original inflammatory trouble.

Villous Tumors of the bladder yield large shreds of tissue,
sometimes containing eapillary blood-vessels choked with blood.
Occasionally fibrinuria temporarily accompanies \'illous tumors.
(Hofmann and Ultzmann).

Pyelitis may be recognized by the presence of pelvic epithelia
and pus-corpuscles. Epithelia from the pelvis of the kidney and
blood-corpuscles are found in pelvic haemorrhage. The urine in
this affection is distinctly acid and laden with uiic acid, which, as
the so-called gravel, is observed in the freshly passed urine.
Ulcerative pyelitis may be recognized by the additional presence
of shi'edsof connective tissue. The pelvic epithelia being in fatty
degeneration, chronic pyelitis may be recognized.

Hfeworrhaf/e from the lidneys is marked by the presence in the
urine of kidney epithelia, red blood-corpuscles, and delicate
shreds of connective tissue ; these are all of a yellow hue, from
the coloring matter of the blood.

The diagnosis of catarrhal nephritis may be made when pus-
corpuscles and kidney epithelia are voided, the presence of col-
umnar epithelia from the straight collecting tubules indicating
an invasion of the pyi'amidal substance. In acute catarrhal
nephritis both the kidney epithelia and pus-corpuscles are numer-
ous ; albumen may be present in a varying quantity, but not
infrequently it is absent during the whole course of the disease.
Small numbers of hyaline casts, mainly from the narrow tubules,
and red blood-corjuiscles, at times accompany the previously
named formations.

In subacute catarrhal nephritis all features may at times be

THE riiiM:. 811

absent, at other times present in varying; nnni]»ers. In rhroiiie
c(if<nrlial injiliritis and its termination, the cinhosis of the hid-
neys, the patient voids hir^e (jnantities of a pak', watery nrine, in
which few or no salts are to be fonnd ; this eonditi<^n will ha more
marked the farther the stajje of shrinkage has advanced. Albu-
men at times is j)resent in small ((uantities, at times al)sent. The
few kidney epithelia and pus-corpuscles are the only reliable
features for diagnosis; sometimes these are accompanied by small
shreds of connective tissue. If the kidney e])ithelia and pus-
corpuscles are finely granular and disintegrated to any gi'eat
extent, the api)roaching end of life may be foretold.

Croupous Xephrifis. All the features of catarrhal nephritis
are present, with the addition of casts. The nature of the casts
allows us to decide whether acute or chronic croupous nephritis is
present. In both instances the amount of albumen is gi-eat, and is
found to be still more abundant if blood is mixed ^vith the urine.
The amount of albumen, the number of the casts and their sizes,
determine the intensity of the inflammatory process. The prog-
nosis is more unfavorable in adults than in children.

If easts characteristic of chronic croupous nephritis are
mixed with casts such as we find in acute croupous nephritis,
the diagnosis of a chronic inflammation with acute recurrence,
/. e., of suljacute croupous nephritis, can be made. The presence
of clusters of delicate fat-granules entangled with the albumen
(if coagulated by the addition of chromic acid) indicates fatty
degeneration of the kidney, the more certainly if fatty casts
are also met with. Waxy degeneration can be diagnosticated
both from the waxy metamorphosis of the shed-off kidney epi-
thelia and the presence of waxy casts. Cases of the recovery
of children even from such a disease are on record. In slowly
running cases of chronic croupous nephritis the prognosis rests
upon the general constitution of the patient, as determined mainly
by the condition of the pus-corpuscles.

8iippurative neplwitia exhibits all the features of acute croup-
ous nephritis, with the addition of very large quantities of pus-
corpuscles. A ruptured abscess of the kidney may be recognized
if, besides numerous i)US-corpuscles, numbers of kidney epithelia
and shreds of connective tissue are also found. The presence of
haematoidin crystals would point toward the chronic course of the
abscess, which may have existed for some time previous to its
evacuation, and which, after bursting, may, for weeks or months,
continue discharging pus.

XXI.

THE MALE GENITAL TRACT.

THE male genital organs are : first, the testes^ which are des-
tined to produce the fructifying principle of reproduction,
t\ie semen or sperm; second, the vas deferens and seminiferous
vesicles, whose ofiice is to carry and store it up ; and third, the
penis, for transferring the spermatic fluid into the female genital
organs. The prostatic and Cowper's glands are accessory organs,
which produce mucus mainly. The spermafozoids are the essen-
tial fructifying element of semen. These are hioplasson forma-
tions, varying greatly in size and shape in different animals. In
man they are pin-shaped, with a thickened head and a thread-like
tail, which at its point of attachment to the head is slightly
conical, exhil)iting either a pear-shaped, a knob-like, or a double
lobate enlargement. The head is of a roundish, ovoid, or conical
shape, the point representing the free proximal end. Their length
is, on an average 0.0040 mm. Sometimes the whole formation ap-
pears homogeneous, and of a high luster. Sometimes a vacuole is
observed in the head, and sometimes a delicate reticular struc-
ture can be traced throughout the thickened portions. Sper-
mafozoids, when in a fresh condition, are in an active wind-
ing or spiral motion, executed by the tail, through which motion
the head is rotated with a boring movement, and at the same
time the spermatozoid changes its place. This motion is favored
by slightly alkaline media, dilute solutions of table-salt, and of
phosphate of sodii ; acids, on the contrary, soon produce rest.

Spermafozoids retain their shape after having lost their
mobility for a long while, even after they have been allowed

77/ A' MAJJ-J (ih'XITAL TltACT.

8i:j

to dry ; nnd tlicy are ])eciiliarly resistant to the aotion of aeids
and alkalies. In the vas (U'ferens they are motionless, there
heinjf but little licjuid present. Ui)on the admixture of niueus
(from the prostate) the spermatozoids at once assume a hij^h
degree of aetivity.

(1) Tlie tcsli's are eomijound tuhulai- <;lands. The seminifer-
ous tubules, originally very numerous, ))yrei)eated union become
fewer, and at last collect into one large tubule — the vas deferens.
The tibrous connective tissue coat, ensheathing the whole organ
(tunica all)uginea), sends jjrolongations carrying the blood-vessels
between the tubuli ; ]»roader septa of connective tissue are also
present, producing an indistinctly lobular structur(Mn the testes;

Fig. 369. — Testis of Adult.

^, tiiulca albtigiiiea : I', liloDil-vcssel : C, connective-tissue frame, <-aiTying blood-vessels,
antl E, E. rows of coarscl.v "riauiilar jdastiils : TS, transverse section of seminiferous tubule ;
OS, oblique section of seminiferous tubule. Magnified '200 diameters.

at their upper posterior aspect, in the corpus Highmori, the septa
are most developed and inclose sinuous spaces. The blood-vessels
are most numerous in the inner portions of the albuginea ; its
smooth, external surface is covered with flat endothelia, which
continue into the so-called serous sheath of the testes. The con-
nective tissue between the tubules, besides the ordinary connect-
ive-tissue corpuscles, holds a varying number of coarsely granular
plastids, which are often arranged in rows, exhibiting a brownish

814 THE MALE GENITAL TliACT.

color resembling tul)ular epitbelia. Their significance is not
understood. (See Fig. 8G9.)

The seminiferous tubules show three marked divisions, which
are: the convoluted, the straight portion, and the rete testis. The
convoluted tubules compose the main mass of the testis, and at
the periphery unite and form a continuous closed net-work having
a few offshoots with blind terminations (Mihalko\dcs.) By con-
tinuous union at acute angles their number decreases toward the
c(n'j)us Highmori ; they gradually become less convoluted, and
continue until, with an abrupt narrowing, they pass into the
straight portion. The caliber of the straight tubules is about
one-third the size of the convoluted. These tubules are imbedded
in a l)road connective-tissue layer, and inosculate with the rete
testis, which forms a dense, narrow, and sinuous net- work of
tubules, occupying the spaces of the corpus Highmori. From
this net- work arise the efferent vessels of the epididymis.

The convoluted tubules have a lining of irregular cuboidal
ej)ithelia, arranged in several layers. The outermost layer is, as
a rule, composed of coarsely granular elements, while the inner
layers are in the condition of rest, either uniformly distributed
or arranged in rows irregularly projecting toward the central
caliber. In the condition of rest the caliber is found either
empty or filled with an albuminous liquid, which, in specimens
hardened in chromic acid, appears finely granular. In some
tubules no trace of spermatozoids can be discerned ; in others,
especially in men who have died of chronic wasting diseases,
the spermatozoids are scanty ; other tubules, on the contrary,
are entirely filled with epithelia, and their offspring the sper-
matozoids. In the rat's testis, and in all animals during the
rutting period, the spermatozoids are in most portions of the
convoluted tubules so numerous that their tails fill the central
caliber, showiiig a spiral, sheave-like arrangement. (See Fig.
370.)

The connective-tissue layer next to the epithelia (the mem-
brana propria) is composed of a number of delicate strata,
which, according to Mihalkovics, are composed of a number of
closely packed, flat endotholia, their nuclei being traceable in a
more or less homogeneous, elastic basis-substance.

Regarding the formation of spermatozoids, the views of in-
vestigators differ widely ; some claiming that only certain
epithelia, the so-called spermatoblasts, participate in the forma-
tion of the spermatozoids, while other epithelia produce mucus

THE MALE UEMTAL TUACT. Hl.j

oiily. My own observations j)rove tliat tlir ra<liatin<; rows of
epithclia coalt'scc into continuctus masses, m tlic most pci-iplicral
portions of which the heads of the spermatozoids are profhiced,
while the tails are f(»rmed l)v the more central i)arts.

The steps in the formation of spermatozoids are as follows :
The epithelia nearest the connective tissne ])ecome coarsely
j^rannlar, and in jjart nucleated ; next we see enlarged epithelia,
in which the bioplassou assumes irregidar, rod-like forms,
arranged without much i-egularity. Then follows a layer com-
posed of coalesced epithelia, the l)ioplasson of which has grown
into bulky formations, which are the heads of the spermatozoids,
while the rods in the central portions of the rows become paral-
lel, and coalesce to form the tails. Around the spernuxtozoids
numbers of unchanged bioplasson-granules are seen, and the

H-

Fig. 370. — Testis op a Rat.

V, counective-tissue slieatU, producing septa between tlie seniiniferous tuljules, in wiiich
course tlie blood-vessels F ; E, rows of epithelia of the seniiniferous tubules ; S, tails of spei-
matozoiils, filling the caliber of the tubule. Magnitied 200 diameters.

first-formed spermatozoids are studded with these granules. As
the liquefaction of the unchanged bioplasson — /. e., the forma-
tion of mucus — proceeds, the tails api^ear smooth and without
any attached granules. Coarsely granular plastids, in limited
numbers, are left unchanged, and mixed with the completed
sperm. (See Fig. 371.)

The epithelia of the straight seminiferous tubules are col-
umnar ; those of the plexus, within the corpus Highmori, are
flat. Neither of these take any part in the formation of sper-
matozoids.

816

THE MALE GENITAL TBACT.

Blood-vessels are numerous in the testis, the capillaries pro-
ducing a reticulum around the seminiferous tu})ules. A closed
reticulum of lymphatics, twiniug around the tubules, has been
known since His, Kolliker, and others.

The Terminations of the Nerves in the Testicle.
By H. G. Beyer, M. D., M. E. C. S., Passed Assistant Surgeon, U. S. N.*

The only observations on the terminations of the nerves within the semi-
niferous tubules at present on record, are those of Letzerich.t He uses either

fresh seminiferous tubules, or such
as have been in a sohition of very
dilute chromic acid for the period
of twenty-four hours ; then he teases
them out carefully witli needles,
and examines them under the mi-
croscope. Under "favorable cir-
cumstances," he finds that the
nerves approach the membrana
propria, perforate the same, and
finally terminate in gi'anular masses
or kiiobs l)etween the latter mem-
brane and the first layer of cells. I
must say that circumstances never
favored me in finding the struct-
ures pictured in the plates accom-
panying his article. In this I have
been no less unfortunate than Von
La Valette St. George. I

The methods of investigation
followed out in my researches re-
quire a brief notice. The testicles
used were those of the dog, calf,
mouse, rat, rooster, and man. Both
teasing and section-cutting were
praticed ; the former method, how-
ever, I found quite superfluous.
The tissues from which the mate-
rial for study was collected were
both fi-esh and hardened, the hard-
ening being done by alcohol, chro-
mic or picric acid. Tlie staining
agents which I found of most ad-
vantage were chloride of gold, osmic acid, picro-earmine, and eosin with
logwood. For the study of the nerve-fibers outside the seminiferous tubules,
and theii' plexiises aroimd the tubules arising fi-om the larger nerve-bundles
which pass along the small arterioles, osmic acid and picro-carmine have, in

371. — Testis of Eat.

F, connective-tissue frame; E, irregular cu-
boidal epitlielia, with rod-like foriiiatioiis of bio-
plasson ; H, epitlielium, in which the rods have
assumed the shape of heads of spevmatozoids:
S, spermatozoids spriinj? from coalesced rows of
epitlielia, some of which have furnished the
heads, others the taUs, of the spermatozoids.
Mat'nified 600 diameters.

Trinted in abstract from the author's nuniusciipt. t " Viichow's .\rcliiv," Bd. 42.
I "Strieker's Handbook of HistoloffV."

THE MALE (lENlTAL TUACT. 817

my hiiiuls, j^ivtMi good results, I can also recommond eosin with logwood for
the saint' purpose, as deserving a trial.

The eiiloridoof gold method is still the only available one for bringing out
the ultimate nerve-terminations. Homo of the most beautiful and convincing
specinu'iis in my possession are sections of the testicles of young rats, which
were hardened in chromic acid and then stained with chloride of gold, in
strict accordance with the rules laid down by C'ohnheim. Such specimens
will show improvement during the first twelve months. It was certainly
a step in advance when Liiwitt introduced his formic acid method, by which
we are eiuxbled to allow the reduction of gold to take place in a dark-
ened bottle. This method, in some cases, gives better and more uniform
results, and reduces the metallic precipitate, so often found on the surface of
sections, to a minimum ; but the destruction of the epithelia which this
process entails is not in all cases desirable.

In hardening, staining and preparing tissues generally, I have prefeiTed to
cut up the testicles into sections of from two to three millimeters in thickness,
and, instead of the imbedding methods, I found it much more convenient to
use the freezing microtome for fine sections. In so doing two things are
avoided — viz. : shrinkage and the introduction of foreign material.

Being obliged to use high powers for the recognition of the ultimate ter-
mination of the axis-fibrilla?, the thinnest sections were chosen and mounted in
glycerine to which one-third of its volume of distilled water had been added.
Specimens stained with osmic acid and picro-carmine can be advantageously
treated after the plan proposed by E. Neumann, which is that of temporarily
mounting in glycerine mixed with muriatic acid in the proportion of two hun-
dred parts of the former to one of the latter, and carefully watching until the
orange-red coloration has been reduced to the nucleus, then washing out
thoroughly in distilled water.

Anatomists agi'ee that the nerves of the testicle are derived from the sym-
pathetic. As long ago as 1S34, Joseph Swan* gave a very good representation
■of the spermatic plexus of nerves. According to Kobert B. Todd,t the nerves
of the testicle are derived chiefly from the renal plexus, but partly also from the
superior mesenteric and aortic plexuses. These nerves then descend in com-
pany with the speiTnatic artery to the cord, where, being joined by branches
from the hypogastric plexus which passes along the vas deferens, they form to-
gether the sperm-plexus. The branches of this plexus are intermingled with
the vessels of the cord, and ultimately terminate within the substance of the
testis. A few twigs may also be traced to the coverings of the gland. Sappey X
recognizes two sources of nerve-supply, namely, one from the plexus accom-
panying the spermatic artery, which, he says, alone penetrates into the sub-
stance of the testis, and the other from the plexus surrounding the vas
deferens, which, according to his view, terminates in the epididymis.

In regard to the nerves running within the structiu'e of the testis, I can
corroborate the views above detailed, namely, that none but non-medullated
nerve-fibers are found ; and I can add that their characteristic arrangement is
in the shape of plexuses. These, when found in the neighborhood of the
larger arterioles, are, of covu'se, large in proportion. As they pass on, always

'-' "A Demoustratiou of tlie Nerves of tlie Human Bodj'," London, Plate V.
t " Cycloijedia of Anatomy and Pliysiolofry," vol. iv., pt. 2, pp. 982.
t " Anatomic Descriptive," tome 4, p. 614.

52

818 THE MALE GENITAL TliACT.

accompanying the blood-vessels, they, by division and frequent branching,
become more numerous and very much smaller, until finally, after having
reached the capillaries, they are extremely thin and transparent, and almost
escape the observer's eye in the fresh and unstained specimen. In success-
ful sections, however, they can still be observed to preserve the plexiform
arrangement. ^Vhen found in the proximity of a seminiferous tulrale, they
are generally situated between a capillary and the basement-membrane. As
they penetrate this membrane, the nerve-fibers, still including several axis-
cylinders, break up into their ultimate fibrilla>, at first pass along between
the several layers of endothelia of whicli the basement-membrane is composed,
and, after having emerged from its inner wall, they, as it were, line its interior
with a plexus consisting of the ultimate axis-fibrilla?, being interrupted only by
variously shaped bodies, most of which present a pyramidal shape. This plexus
thus lining the inner surface of a seminiferous tubule is best observed in the
testicles of animals in which the membrana propria is very thin and is com-
posed of but one layer of endothelia, such as the mouse and the rat. From this
plexus, best seen in gold preparations, viz.: longitudinal sections which have
lost most of their epithelium, so as to expose the inner surface of the semi-
niferous tubule, the axis-fibrillse pass upward at acute angles in a direction
toward the center of the tubule. Between the epithelia superimposed upon
the membrana propria, the fibrillge anastomose in every direction, and hold,
so to say, the epithelia in a mesh-work. The best and most clearly defined
pictures are represented in specimens of the testicle of the young rat.

The cement-substance Jwtwecn the epitheJia is the plan of the ultimate termina-
tion of the axis-fihriUa in the testicle.

I have never seen a nerve-fiber penetrate into the interior of an epithe-
lium, although it might seem so when one of them crosses an epithelium and
is interrupted in its course.

The ultimate axis-fibrillas, having been traced traversing the cement-
substance between the epithelia, and being connected with the filaments or
prickles crossing them, we are at once in a position to understand how the func-
tion of the epithelia within the seminiferous tubules — viz.: the production
of spermatozoids — is under the direct control of the sympathetic system.

(2) The epididymis is composed of a single tubule with numer-
ous convolutions, with which the seminiferous tubules unite after
leaving the corpus Highmori, and producing the convoluted coni
vasculosi. These tubules are now termed efferent. They all
have a circular coat of smooth muscle-fibers, external to the mem-
brana propria. The epithelia are columnar, (-iliated, numerous
smaller, wedged plastids being present between their pointed feet.
Toward the cauda epididymidis the wall of the efferent vessel in-
creases in thickness, and is supplied with longitudinal muscle-
bundles. A delicate, adventitial connective tissue, rich in elastic
fibers, supports the convolutions of the tubule of the epididymis,
being rich in capillary l)l()od- and lymph-vessels. These eii'culate
through the adventitial coat, penetrate the muscle-layer, and pro-
duce a terminal capillary plexus above the epithelia.

THE MAIJ-: dKMTM. TltACT. 819

(;{) The vds il('/( reus lias a hroad wall, which is composed
mainly of three layers of smooth musclc-fihei-s — an iiiiiei' and
onter lon<j:itudiiiMl niul ;i ini(hllt' circular layer. (See Fig. 872.)

The most internal mucous layer, Avhen the tulmle is empty, is
arranged in folds, and covered with a single layer of columnar
epitlielia. The ouly vas deferens which I liav^e examined exhib-
ited eiliated columnar epithelium; all authors claim, however,
that eilia are not i)i-esent. The bundles of the l(mj>itndinal mus-
ele-layers are h)osely arranged, and freely intermixed with
fibrous connective tissue abundantly furnished with elastic fibers,

"^■T/>

^1 ' ■.-'^'''

C^-'

C^^s^

Fig. 372. — Vas Deferens. Transverse Section.

E, folds of the mucosa-, covered with columnar epithelia; M, mucous layer, comi)osed of
delicate bundles of connective tissue ; C, inner longitudinal, d. outer longitudinal, layer of
bundles of smooth muscle-libers, freely intermixed with connective tissue ; T, circular mus-
cle-layer ; 0, adventitial connective tissue, carrying the larger blood-vessels. Magnified 100
diameters.

while in the circular layer the muscle-buntUes are arranged more
closely. The most external layer is composed of loose, fibrous
connective tissue, rich in blood-vessels, lymphatics, and nerves.

(4) The ampulla of the vas deferens and the seminal vesicles
have walls considerably thinner than those of the vas deferens
proper. In the ampulla the mucosa has abrupt folds, and the

820 THE MALE GENITAL TRACT.

lining: columnar epithelium sends prolongations into the connect-
ive tissue — the glandular nature of which is not generally
agreed upon, as some observers claim these formations to be
merely sinuosities of the mucosa. The epithelia contain a vary-
ing number of brown pigment-granules. Three layers of smooth
muscle-fibers are discernible. Similar structures are found in the
walls of the seminal vesicles. The ejaculatonj ducts are covered
with ciliated columnar epithelia (authors do not mention the
cilia), and the muscle-layers are said to be only an inner 'longitu-
dinal and an outer circular. Toward the opening at the summit
of the seminal hill, the epithelia gradually change into a stratified
formation composed of several layers. In this situation the
mucosa has numerous sinuous veins, agreeing Avith the general
structure of the male urethra.

(5) As remnants of embryonal formations are considered:

The 2>arndidy7rris (Girald^s), wMeh consists of single or multiple lobules
at the vascular porta of the testis, between the blood-vessels of the spermatic
cord; each lobule being composed of convoluted tubules, with a blind termi-
nation, and lined with ciliated columnar epithelia. It is considered to be a
remnant of the primordial kidney (Wolff's body), being homologous with the
parovary of the female.

The ra.s aherrans HalJeri and the rasa aberrantia of the rete testis (M. Roth)
are blind tubules, kindred in structure to the tubule of the epididymis and the
tubules in the corpus Highmori. Both are remnants of the genital portion of
Wolff's body.

The hydatid of Morgayiii is a non-pediculated lobule at the anterior aspect
of the testis, immediately in front of the head of the globe. It is composed
of vascularized connective tissue, and covered with ciliated epithelia, which,
according to E. Fleischl, send prolongations into the depth of the hydatid.
The center holds a canal, which is lined with ciliated epithelia; this canal
may be widened into a vesicle, and, if in communication with the tubule of
the epididymis, is found filled with semen (Lusehka). It is considered as an
analogy of the ovary.

The peduncuJated hydatid is not constant; it is a vesicle the size of a
millet-seed, attached to the head of the epididymis by means of a slender
pedicle. It is a remnant of the embryonal Miiller's duct (Krause).

(G) The pyostate gland surrounds the initial portion of the
male urethra, mainly at its posterior and lateral circumference.
It is composed of acinous glands, which exhibit numerous con-
volutions, and are lined with cuboidal epithelia in several layers.
The acini are sometimes small in comparison with the large
ducts, which are lined with columnar epithelia ; sometimes
the acini are imperfectly developed, and the ducts seem to rep-
resent chiefly the glandular structure. In the acini, not infre-

Tin: MALI'! (iKXJTAL T1{A(T. 821

qn«'iitly, ix'culiai", coiicciitrically sti'iatcd colloid (•<)r])uscl«'s of a
lii«^li luster arc observed — the so-called prostatic; eoiiei-etioiis.

According to Langerhans, the epithelia of the gland are
arranged in two layers, the superficial l)eing conical and elon-
gated, the deeper globular; Toldt maintains having seen this
arrangement in one prostate gland, while in three others which
he studied only one layer of columnar ei)ithelia was present.
There seem to be vaiieties in the arrangement of the glandular
epitheliji. The interstitial tissue is scantily supjdied with con-
nective tissue, but plentifully with, smooth muscle-fibers, which
are arranged without any apparent regularity. At the peripheiy
of the jn'ostate gland the muscle-bundles coalesce, forming con-
tinnous layers, and in this situation are freely intermixed wdth

jir-

m^m^.

Fig. 373. — Prostate Gland of an Adult.

M. interstitial connective tissue, rich in bundles of smooth muscle-tibers : F, cuboidal
epithelia, lining the convoluted acini ; C, i)rostatic concretions. Magnified 200 diameters.

striped mnscles, which surronnd the gland. The smooth muscle-
layers are continuous with the circular sphincter muscles of the
bladder.

(7) Coii'pei^s glands are acinous glands, w4th irregular sinu-
osities and stratified cuboidal epithelia. The lobules of these
glands are separated from each other by dense fibrous connective
tissue, which is traversed at the peripheral portions by bundles

822

THE MALE GENITAL TRACT.

of striped muscle-fibers of the perineal tracjt. Sometimes the
lobules are separated by the intervening connective and muscle-
tissues.

(8) The penis consists of two cavernous bodies, which in their
under furrow hold the urethra, surrounded by a cavernous body
of its own. The cavernous body is composed of trabeculfie of
dense connective tissue, rich in smooth muscle-fibers, capillary
blood-vessels, and medullated nerves. (See Fig. 374.)

The trabecuhp inclose venous sinuses, and at the boundary
surface are lined with flat endothelia. These sinuous spaces are
coarsest in the cavernous bodies of the penis, somewhat smaller
in the glans, and smallest in the cavernous body of the urethra.
According to C. Langer, the arteries which supply the cavernous

Fig. 374. — Cavernous Body of the Pexis. Transverse Section.

A, tunica albuginea ; 8, venous sinuses ; T, trabeculse of connective tissue, holding capil-
lary blood-vessels C, anil bundles of medullated uerve-fibers A^ Magnified 200 diameters.

bodies are marked by a broad muscular coat, and they anas-
tomose freely within the trabeculae. Some of them empty
directly into the sinuses of the cavernous body, and others
divide into capillaries which run below the albuginea and along
the septum, producing a delicate reticulum which inosculates
with the venous sinuses, and are the main source of blood-
supply to the latter. The sinuses are smaller at the periphery
than in the center of the cavernous bodies. It is an unsettled
question whether the capillaries of the trabeculae themselves,
which produce a wider mesh-work than those at the periphery,

■/•///•; M.ii.i-: ci'.MiAL rincj: 823

;ils(» empty into the vi-iioiis sinuses. The Ix'i'oi'e-iiiiiiied observer
and Ixoiiiict have denumstrated that the so-eaHed arterial heli-
eiiue, which lake n spii'al eoui'se, and are found mostly in tlie
posterior portions of the eori)ora eavernosa, ai-e <july tlie h)oi)s of
arteries visible in the <!oUapsed eondition of the penis, and which
have no eeeal terminations, as former anatomists t]iou<i-lit.
Nevertheless, Henle maintains tlie existenee of helieine — Idind
vessels — and considers them as a sort of ^'landular apparatus.
The efferent veins collect on the upper and under surface of the
penis, uniting" mainly in the vena dorsalis penis ; those of the
under surface receive the blood from the lari»'e cavernous sinuses.
The inner surface of all these veins is richly provided with ledj^e-
like, branchinar projections, which are composed of smooth
nniscle-fibers ; free trabecular of a similar structure also trav-
erse the calibei's of the veins.

XXII.

THE FEMALE GENITAL TRACT.

THE female genital organs are : first, the ovaries, whose
office is to prodnce the essential principle of reproduction —
i. €., the ovnm ; second, the uterus^ to retain the fructified ovum
during the period of development; and third, the vagina, to
receive the seminal fluid of the male for fructification. The
organ, upon which reproduction mainly depends, is the ovum.
The mature human ovum is a globular vesicle of an average
diameter of 0.200 mm., inclosed by a cuticular sheath — the zona
pellucida — in which delicate radiating striations are seen. In the
ova of many animals the cuticle is known to be perforated by an
opening — the micropyU — to admit the entrance of the spermato-
zoids. The ovum contains granules which are partly minute,
partly coarse, representing the yolk, and also an eccentrically
situated, nucleus-like formation — the vesiciila genninativa — the
bioplasson of which is distinctly reticular, holding in its center a
somewhat coarser granule — the macula germinativa.

The matured ovum is discharged from the ovary a few da,vs before the
begiuningof menstruation. It is carried by the Fallopian tube into the cavity
of the uterus, and in any locality, after leaving the ovarian follicle, may be
reached by the spermatozoids. The number of the spermatozoids which
penetrate the ovum is known to vary greatly, although, perhaps, a single
spermatozoid is sufficient for the impregnation of the ovum. As regards the
determination of the sex, all obsei'vers since Aristotle's time point toward the
fact that the sex of the future being is determined in the moment when
impregnation takes place. Careful observations of stock-farmers and of
physicians in lying-in hospitals have settled the fact that, when coition takes
place shortly before the appearance of menstruation, or in animals at the begin-

rill': FKMALi': aKsiiAL tuact. H2r>

ning of hi'iit, tlu< olTsjuiiif^isii foimilt'. If, on the coiitniry, iiiipri'KHution occurs
shortly after iiienstruation, or in animals toward the end of the ruttinf< period,
a male is the resnlt. Based upon these facts, the followinj^ hyijotliesis is
admissible: Before menstruation the ovum, beinfj hij^h nj) in the female
penital tract, can he reached by a few spermatozoids only ; while, after men-
struation, the ovum lyiuf? in the lower jmrt of the uterine cavity, can after coitus
be reached by a larger number of spermatozoids. The ovum is a formation
of living; matter of the female, the spermatozoid a formation of living? matter
of the nmle. Both have plastidwlcs representative of the oriinniam in toto ;
and if after comminf^liuf^the liviiij^Tuatter of the female be in excess, oidy one
or a few spernnitozoids having entered the ovum, a female organism will be
produced. Should, oii the contrary, jnany sjK'rmatozoids have entered the
ovum, the living matter of the father will predominate over that of the mother,
and the result will be a male organism. This hypotliesis may sustain the idea
that the sex of the future individual is determined i7i the moment of impreg-
nation; it also agrees with the fact that peculiar bodily or mental properties
of the father are, in the majority of eases, transferred to the male offspring,
while bodily and mental properties of the mother usually reappear in the
female children, though all these characteristics may, in varying proportions,
be present in either sex, since every new being is the result of a mixture of
male and female living matter. Exceptionally, however, characteristics
peculiar to the father, f. i., a hare-lip, reappear in the female offspring exclu-
sively, for which fact the above hyj)othesis offers no satisfactory explanation.
Neither can it be understood how, in some insects (f. i., bees), male offspring
are produceil independently of the male — i.e., without sexual intereoui'se.
This strange peculiarity, to which Sieboldt first drew attention, cannot be
understood by any theory yet advanced, and we must rest satisfied for its
designation with the Greek word " parthenogenesis."

(1) The Orarj/. The essential eharacteristies of the ovarj' are
its epithelia, which Waldeyer terms the ^' (jerminal epitheUumP
This observer discovered that the peritoneum produces no cover
for the ovary, Init terminates with a jao'j^ed border at the hilus
of this organ. The surface of the ovary, at all periods of life,
is covered by one layer of columnar or cuboidal epithelia ;
these are the remains of the germinal epithelium which gives
origin, in the earliest stages of embryonal development, to all
glandular formations of the genito-urinary tract. Among the
germinal columnar epithelia Waldeyer found larger epithelia
of a globular shape, with a large, sharply defined nucleus, which,
according to him, are developed into ova. My own researches,
though limited, point toward the conception that the ovum is the
product, not of a single epithelium, but of quite a number of
them, which by coalescence at first produce multinuclear bodies,
and later exhibit only one larger central nucleus as a secondaiy
formation.

All glandular formations of the ovary arise, according to

826 THE FEMALE GENITAL THACT.

Waldeyer, from a proliferation of the germinal epithelia, which
is accompanied l)y an outgrowth of connective tissue from the
center toward the periphery. The germinal epithelia produce
prolongations in the shape of tubules or solid strings, which at
fii'st are connected, holding in their centers rows of larger nucle-
ated epithelia — the '' ovular chains" of Pfiiiger. At the time of
Mrtli, such cord-like formations, in a plexiform arrangement, are
still recognizable, though, in the depth of the organ, numerous
epithelial groups appear already isolated by surroiniding con-
nective tissue, being, at this stage, tei-med the folJides of the
ovarii. Each follicle is a globular formation, composed of a sin-
gle lining row of short, columnar epithelia, surrounding a finely
granular, central, nucleated body — the ovum. In more advanced
stages of development the connection between the surface epithe-
lium and the epithelial follicles disappears, and each follicle is
surrounded and enclosed by its own layer of connective tissue.
Exceptionally, two ova are observed in one follicle.

As development progresses, numerous layers of cuboidal epi-
thelia are gradually formed within the follicle, and only the layer
nearest the wall of the follicle and the layer lying close around
the ovum retain their columnar character. The row of col-
umnar epithelia immediately surrounding the ovum is termed
the zona (jranulosa ov radiata ; between this and the ovum proper
— which, as before mentioned, is also epithelial in nature — a
broad, cuticular formation is developed — the zona pellucida.
Numerous cuboidal epithelia are transformed into a mucous
mass, which is subsequently changed by liquefaction into what
is termed the follicular liquid. Traversing the ca\aty of the fol-
licle, comparatively few epithelial strings are left of an irregu-
lar shape. The ovum, approaching its maturity, is either
suspended by such epithelial strings or remains attached to the
wall of the follicle, usually opposite the pole of the follicle which
looks toward the periphery of the ovar}'. (See Fig. 375.)

With advancing gro^i^h the follicle — called Graafian follicle
— becomes easily discerned with the naked eye, and exhibits a
distinct layer of inclosing fibrous connective tissue. — the fJieca
folliculi, — which is in continuity with the connective-tissue
stroma of the ovary, and shows an ample supply of capillary
blood-vessels. Between the theca and the adjacent columnar
epithelia lining the follicle a marked basement- or elastic layer
may be observed. The point where the follicular epithelium is
accumulated around the ovum bears the name of the prolicjerous

THE FEMALE (iESElAL TltACT.

827

disk, wliicli ])r()tnult's more or less toward tho central favity.
Near tlu' tinio of maturity of the ovum, the cpitlidia of the tolli-
cle opposite the disk are destroyed, the eonnective tissue around
the follicle is deprived of its blood-vessels, and this thinned por-
tion ruptures ; the follicle empties its liquid, and the ovum is
discharired, still surrounded by a layer of columnar epithelia —
the zona (jramdosa or nulinta of authors.

After the follicle has emptied, a slig:ht haBmorrhaj^e takes
place at the site of the former cavity. The extravasated blood
leaves a certain amount of pigment l)ehin(l, and the newly ap-

Fig. 375. — Follicle of the Ovary of a Rabbit.

C, dense couDeetive tissue — so-called capsule of ovarj- ; T, libious connective tissue — the
stroma of the ovarj- ; £, stratified liuintr epithelium of the follicle; <S', epithelial strings trav-
ersing the cavity of the follicle; Z, albuminous liquid lilliiifr the cavity of the follicle ; ZG,
zona granulosa, composed of columnar epithelia ; ZP. zona pellucida — a cuticular formation;
O, ovum witli the vesicula geiTuinativa. Magnified ^00 diameters.

pearing medullary corpuscles, both from the connective tissue
and the epithelia of the follicle, appear laden with pigment-
particles, or saturated by a diffuse coloring matter. At a certain
period a number of pigmented medullary or inflammatory cor-
puscles appear in the part where the former follicle was situated ;
these are more numerous and more laden with pigment when

828 THE FEMALE GENITAL TRACT.

the discharji'ed ovum is iiiipre^nated and the rupture of the
follicle followed by preg-iianey. The difference between a false
corpus luteum (after menstruation) and a true corpus luteiim (after
pref^nancy) consists only in the number of medullary corpuscles
and the amount of pigment present. The coloring matter has
the characteristics of ha^matoidin, and gives the corpus luteum a
yellow tint. This color gradually fades, till at last all pigment
is absorbed, and only the shreds of the basement or elastic mem-
brane of the former follicle are left behind, im])edded in cica-
tricial fibrous connective tissue, the shrinkage of which causes a
retraction at the surface of the ovary. The folded, homogeneous
shreds are easily recognizable under the microscope by the deep
carmine stain which they take up.

According to Bisehoff, in most instances the formation of the
follicles and the ova is completed in foetal life or during the first
few years after birth, and it is doubtful whether a new formation
occurs in more advanced age. Out of the enormous number of
follicles — Henle estimated in the ovary of a girl eigliteen years
old thirty-six thousand — probably many never reach full devel-
opment. Beginning from early childliood, however, during the
procreative period all stages of development of follicles and
ova are found in the ovaries, the more fully developed lying in
the deeper portions of the cortical substance. Upon reaching
maturity the follicles occupy the whole width of the cortex, and
even slightly protrude from the surface. The ovary after the
menopause shows no follicles, but only dense, fibrosis connective
tissue, with a varying amount of the remains of foUicidar base-
ment-membranes.

The connective tissue of the ovary is accumulated at its
center, in connection with the hilus, through which the larger
blood-vessels enter the stroma. The connec^tive tissue is com-
posed of interlacing bundles, plentifully supplied with smooth
muscle-fibers. Only the peripheral portion of the ovary, the
cortex, contains the follicular formations, and, at least in young
individuals, the connective tissue of the cortex, between the fol-
licles, is of the myxomatous variety. In older persons it has
the character of fibrous tissue, which is most abundant at the
periphery in the shape of a dense capsule. Such a tunica albu-
ginea does not exist around the ovaries of children or of young
animals (Waldeyer).

The blood-vessels of the ovary penetrate the hilus through the
broad ligament ; the largest amount of blood-vessels is found in

THE FKMM.I-: (IF.MTAL TRACT. 821)

that i)art of tlic lui'tlullarv portion which is nearest the cortex,
and the latter receives capilhii-ies ahnost exchisively. The arter-
ies have a markedly spiral course and a l)road muscle-coat, while
the veins have verv thin walls, and in the rej^ion around the
hihis produce a rich jdexus, aj)pr()a('hinj? the cavernous structure.
Lymph-vessels are also numerous, and, accoi'dinj; to His, ])roduce
a closed reticulum, in the stroma as wi'll as in the connective-
tissue capsule of the follicles. Valves are found in the lymph-
atics outside the ovary, and also in th(^ lym])hatics of the l)road
ligament.

As rtuiainx of onhnjonal foriiKitioiis ar»^ coiisi(l(M'o<l :

(1) The t'luniphortin (Koseniniiller), whicli lies in the hiteral portion of the
broad ligament, above the ovary, reaehinp to the hilns. It is composed of
blind tnbules, with a lininjj of eolumnar, ciliated epitlielia. They are rem-
nants of tlie sexual portion of Wollf's body.

(2) The parnoplmroii (Waldeyer). This is located in the medial portion
of the broad ligament, often extending to the l-iteral border of the uterus.
It is likewise composed of tubules lined by columnar, ciliated epithelia, and
is considered astlie remains of the ju-imortlial kidney (Wolff's body).

(2) The oviducts or FallopUni inhes are composed of connect-
ive tissue, the innermost layer l)eing the mucosa, the outermost
the serosa, and between these are layers of smooth muscle-fil)ers.
The mucosa has abrupt, h)ngitudinal folds, which, toward the
ampulla, are connected by oblique and transverse ridges, supplied
Avith numerous snuiller ledges. The portion nearest the epi-
thelium is in young persons myxomatous, in older persons loose
fibrous connective tissue, having longitudinal bundles of smooth
muscles, more fully developed toward the uterine than toward
the fimbriated extremity of the tul)es. The submucous layer
above the muscles is always fibrous connective tissue. The
covering epithelia are ciliated columnar, extending over the
fiml)ria\ but, in human beings, not connected with the epithelia
of the ovary. Of the muscle-layers the circular shows the n'ost
advanced development; the longitudinal, outside the cii'cular,
is composed of only a few scanty bundles. The subserous con-
nective tissue is well developed, and bounded by the delicate
but dense fibrous tissue of the peritoneum. The mucosa, close
above the epithelium, has a rich reticulum of capillary blood-
vessels.

(3) The u ferns is composed mainly of smooth muscle-fibers,
which toward the cavity are covered by the mucosa; at the
periphery, in a great extent, by the peritoneum. The mucosa is

830 THE FEMALE GENITAL TRACT.

mjTcoraatous connective tissue, crowded ^vith lymph-corpuscles,
so-called adenoid tissue, being uniform in structui'e throu.trhout
its breadth. The surface is smooth within the caWty, folded in
the cervical canal, and supplied with conical papillae on the
external cervical portion ; in the latter situation the mucosa is
composed of delicate fllu-ous connective tissue, without hnnph-
corpuscles.

The mucosa of the uterus is lined with ciliated columnar
epithelia. extending- downward into the upper two-thirds of the
eer%'ical canal. Here, at somewhat varying depths, it blends
with the stratified epithelium which covers the mucosa of the
lower end of the canal and the external portion of the cortex. The
larger plicae palmata? at their summits may exhibit stratified
epithelium, while in the fuiTows between them columnar ciliated
epithelia are present (Toldt). The sui-face epithelium sends
numerous prolongations into the depth of the mucosa, producing
the tubular utricular ylatids, which take a radiating and slightly
winding course ; many of these ai-e bifurcated, and send off
lateral branches. The lining epithelia of the glands are col-
umnar ciliated, the current of the ciliary motion being spiral
from the bottom toward the mouth of the gland (Lott). In the
cervical canal the glands are less numerous than in the body of
the uterus, and, besides the long, tubular formations, small pear-
shaped glands are found, which are lined with short columnar
or cuboidal epithelium. Their h^^i^ertrophy and occlusion is
supposed to be the cause of the common cystic formations
termed o\Tiles of Naboth.

The muscle-layer of the uterus is composed of circular, longi-
tudinal, and oblique bundles interlacing, without any apparent
regularity. A regular arrangement into a middle circular layer,
and internal and external longitudinal layers, can be traced in
the cer\ical portion onlv. In the bodv of the uterus all lavers
contain circular and longitudinal bundles ; these are more abun-
dant, however, in the submucous and subserous layers, while in
the middle portions of the uterine wall, especially at the place of
transition of the cer\ical into the uterine ea^^ty, the circular
fibers are most numerous. An apparent boundary between the
middle and the outer layers is established by the large number
of arterial and venous blood-vessels, which are present in this
situation. The subserous longitudinal fillers are partly con-
tinued into the broad ligaments, while the circular fibers can be
traced into the initial portion of the round ligaments. The sub-

/•///•; Fi-.MM.h: (n-iMTM. ruAcr. 8;n

muoous niuscU'-lmiHlli's st'iid dclicato in'oloii^utious into tlie
mucosa, aiul take a ciiTular course around the opcninpfs of the
Fallopian tulx's.

The urtcrics of the uterus are nuirked by a winding, spiral
course aud a heavy muscle-coat ; they branch usually at the
))oundary of tin* middle uterine muscle-layer — the so-called
stratum vasculare. The cai)illary net-work is richest in the
mucosa close above the epithelium. The veins are character-
ized by their thin walls and numerous sinuosities; they produce
a narrow plexus in the stratnni vasculare, and a coarse ])lexus on
both sides of the body of the uterus. The lymphatics form a
capillary plexus, with numerous blind terminations, in the mu-
cosa, and another plexus in the subserous connective tissue, while
the muscle-layers have fewer lymi)hatics. As to the termination
of the nerves, nothing positive is known.

The tissue-changes that occur in menstnuition are understood only in part,
as shown by the following article. Still more obscure are the tissue-changes
during pregnancy and involution. The source of the enormous new formation
of myxomatous tissue, resulting in the production of the placenta and the
very abundant increase of the muscle-tissue of the uterus in pregnancy, are
still puzzles, notwithstanding the amount of literature treating of this subject.

The iKiihology of the uterus needs a more careful microscopical study than
has yet been made. The origin of tumors to which it is subject is little
understood. Among these are the common myo-fibroma, myxo-adenoma,
myxo-angioma, as representatives of the benign type, and carcinoma — usually
starting from the cervical portion, and exceptionally fi-om the mucosa of the
body and the fundus uteri — as a representative of the malignant type.
Peculiar tumors are the lymph-adenoma or myxo-adenoma of the mucosa,
which are considered to be the result of chronic endometiitis. The tissue of
these tumors — of which I have examined quite a number — consists of lymph-
tissue with interspersed utricular glands ; this structiu-e bears a close resem-
blance to myxo-myeloma ; and, nevertheless, experience teaches that by a
thorough removal of the newly formed tissue with the ciirette a permanent
cure can sometimes be obtained. The boundary between Ijnuph-adenoma and
myxo-myeloma has not, yet been defined.

A peculiar complication, misleading the microscopist, occurred in the fol-
lowing case : Dr. D. brought me a tumor the size of a pigeon's egg, claiming
that it was removed fi-om the uterus. Under the microscope it proved to be
colloid cancer — therefore, malignant. A few days later. Dr. M. brought shreds
which he had gouged out from the "internal genitals"; microscopic exam-
ination revealed cicatricial connective tissue — therefore, something benign.
Both specimens proved to have come from a lady with an idcerating cavity
behind the uterus, which had perforated the posterior cul-de-sac into the
vagina. The main tumor was colloid cancer, evidently starting from the rec-
tum, while the shi-eds had been removed from a place previously operated
upon — therefore, a cicatrix. Dr. M., anxious to clear up the case, gouged out

832 THE FEMALE GENITAL TRACT.

other shreds from the cavity, and handed tliem to another microseopist, Dr.
Dd., of this city, being known as a reliable man. He diagnosed cicatricial tis-
sue. The tnmor was then given him, and tlie diagnosis was colloid cancer.

Microscopical Studies on the Catamenial Decidua.
By Jeannette B. Greene, M. D., New-York.*

At the present time, it is agreed by all histologists that no new formation
of a tissue can take place exceirt through embryonal elements. Morbid, as
well as normal tissues, develop from an original indifferent or medullary for-
mation, which is known to constitute the body of the animal embryo in the
earliest stages of its existence.

Whenever one tissue is about to be transformed into another, the original
•one first breaks down into medullary elements — that is, it falls back into the
earliest stage of embryonal development — from which a new tissue may
arise.

The same process invariably takes place when, from an original normal
tissue, a new formation starts. This new formation may be inflammatory in
its nature, and, as such, limited in its course ; or it may be a new formation
without typical termination — a so-called neoplasm or tumor ; it makes no
difference, the process is the same.

The peculiar condition which sometimes occurs at the menstrual period,
producing membranous discharges, — called " decidua catamenialis " or "dys-
menorrhea membranacea," — is known to be anew formation from the mu-
cous membrane of either the uterus or vagina, or both. This process is inde-
pendent of pregnancy. It is observed only at the time of menstruation, and
is unquestionably caused by an irritation of the mucosa of the genital tract.
This irritation is a constituent part of normal menstruation, and, as well-
observed cases show, the only process which takes place whenever both ova-
ries are absent. This irritation miist reach a higher degree than in normal
menstruation, in order to produce a menstrual decidua.

My purpose is to present the anatomical features of uterine decidual mem-
branes. The materials for my studies were found in the laboratory of Dr.
Heitzmann, of this city; they consisted of five specimens. These had
been preserved in alcohol, and, a few weeks before examination, had been
placed in a weak solution of chromic acid — about one-sixth per cent. After
sirfficient hardening, the specimens were imbedded in a mixture of wax and
paraffin, and were cut into thin sections for microscopical examination.

Under the microscope, all the specimens proved to be composed of medul-
lary corpuscles and a relatively small amount of basis-substance, the latter in
its myxomatous and fibrous varieties. The fibrous exhibited both the reticu-
lar arrangement and that of bundles composed of fine fusiform bodies in the
earliest stage of development.

In all specimens, glandular formations of a tubular natm'e were present,
lined by columnar ciliated epithelia — very probably the remains of original
utricular glands, and not newly formed.

Under a power of five hundred diameters the medullary corpuscles pre-
sented mostly a globular shape ; the globules were somewhat flattened at

* Abstract of tlio autlior's essay. TJie American Journal of Obstetrics and Diseases of
Women and Children, vol. xv.', Aiiril, 1882.

yv//'.' ii:mm.e a j:\itai. tuact. 883

tlicir parts of contact. Scattered ainoiij^ tlic jilol)\ilar I'lcmcnts were oMoiifj,
siiiiMlli'-sliapcd t'ormations, frciinciitly aiTaiif;<'(l in clusters. All iheso bodies
wore invariably sei>arated from each other, either by very narrow rims or by
fields of a slij^htly jjranidar snlislance, which lields were about the size of an
orif^inal medullary corpuscde. Clusters of such nie<lullary corpus(des were
irregularly traversed and bounded by slender bundles of fibrous tissue. The
niedidlary cori)uscles di<l not ajipear uniform. Some were aboiit the size of
red blood-disks, aiul almost without structui'i^ ; others wei'e rather larj^er and
indistinctly j^ranular; others again, the larj^est, showed a distinct j^raiiulation
and a central nucleus. The relative proportion of these three varieties varied
gi'eatly in the difTereut specimens. In one ease, the shiuing, homogeneous
bodies were largely in excess. In another, the large, pale, granular bodies
were most abundant, and the intervening spaces unusually broad. In a third
case, the small, homogeneous bodies were scanty, while the pale, granular
corpuscles were numerous, and about six times the size of the homogeneous
ones. Their granulations were so coarse as to conceal tlie nucleus. The cor-
puscles exhibiteda distinct arrangement in clusters, and between the clusters
delicate fibrilla? could be traced, thus producing the appearance of myxoma-
tous tissue. In a fourth specimen the smallest l^odies were few in number ;
the large, gi-auidar ones surpassed in size the smaller by six or eight diame-
ters. In many of these larger bodies the granulations were pale, evidently
due to a formation of basis-substance, the nucleus very distinct, and the
interstices had the appearance of a fibrous net-work resembling placental
structure. The fifth ease was so different from the others as to require a more
detailed description.

High powers of the microscope (one thousand diameters) proved that this
mass of embryonal coi-jjuscles deserved the name of a tissue from the fact
that all the bodies, of whatever size, were united by delicate filaments. No
structure Avas defined in the smallest corpuscles. The larger ones showed
vacuoles in their interior, while in the largest a reticulum could be traced
whose points of intersection, with low powers, appeared to be granular. The
reticulum was most marked in the finely granulated corpuscles with distinct
nuclei, and the granulations within the nucleus also had the appearance of
being connected in a net-like structure. The reticular formation crossing the
plastids became continuous with all their neighbors through the delicate fila-
ments traversing the light rims. The gi-anular fields lying around these bod-
ies exhibited only a faint reticulum ; but still, this was united with the
medullary corpuscles by the points arising from their peripheries.

"Wlierever fibrillfe were found, either in bundles or as a reticulum inclosing
single or grouped corpuscles, these fibers were invarialdy composed of min-
ute, spindle-like formations. These spindles showed a reticular structure, and
were also joined to neighboring plastids by fine threads. (See Fig. 37(i.)

In the specimens of deeidua studied by me, the smallest bodies represent
the earliest stages of development of living matter, and fi-om these globules
arose the nucleated plastids, which were considerably enlarged from imbi-
bition of a liquid. Here the living matter has passed into the reticular stage
of development. In a more advanced condition the plastids had been trans-
formed into basis-substance which was either fibrous or myxomatous in char-
acter, and remained traversed by a reticulum of living matter. The light
fields around the medullary elements were made up of a myxomatous basis-
53

834

THE FEMALE GENITAL TRACT.

siibstanee, aud this substance composed the mass in which lay the unchanged
central nuclei described in the fourth case.

Fibrous l)asis-substance may appear in the form of straight bundles in-
closing myxomatous fields. It is obvious that in this condition the liquid
contained in the original medullary corpuscles must have been transfonned
into a solid basis-substance, while the living matter itself remained un-
changed. Living matter in a reticidar arrangement first crosses the liquid,
and afterward the interstitial solid basis-substance. The fibrous basis-sub-
stance is always composed of slender spindles, which indicate that the
plastids had become elongated and divided up before a solidification of their
liquiil had taken place.

All specimens showed a varying amount of blood-vessels in longitudinal,
transverse, and oblique sections. Capillary vessels were most abundant,

Fig. 370. — Decidua Catamenialis.

.V, niicle.ited infthillary corpuscles ; .S', tlie medullary corpuscli-s si)lit into spirirtlcs ; -V.
snch corpuscles transfuriiied to basis-substauce, tlie nuclei remalnui^ unchanged ; J?, colum-
nar ciliated epitliclium of a utricular .irlainl. Magnified 1000 diameters.

being recognized as such by their flat, endothelial lining. In one of the speci-
mens scanty formations of vessels resembling arteries were observed. In
another case, arterial vessels were unmistakably present, characterized by
the muscular coat. All stages of arterial development could be traced. In
some parts there were only cord-like formations with parallel outlines, com-
posed of small medullary corpuscles which flattened each other, rendering
their shape polyhedral. The outer corpuscles, seen in front view, appeared
fusiform, so as to encircle the cord. Transverse sections of such a formation
in some instances exhibited medullary bodies arranged in a radiating man-

THE FF.MALH (iKXITM. TUACT.

835

ner, but witliout a clt'iirly marked c-alibor. In other parts, a central liy'it
space could be discerned, evidently the first trace of the future lumen. This
openiu'^ must have been produced by the vacuolation of the most inner
medullary bodies. Some cord-like formations whidi, if viewed transversely,
still appeared solid, when seen in lon<jituilinal sectioii, sliowed a narrow,
central caliber, lined by delicate spindle-shaped bodies in lengthwise arrange-
meut, corresponding to the endothelial coat of arteries. (See Fig. 'Ml.)

In a more advancetl stage of development, the artery liad the apjiearance
of a tube with a clearly nnirked caliber; l>ut in the opening there could be
seen clusters of granules or nuclei, evidently the remnants of former vaeu-
oled medullary corpuscles.

In addition to these, other bodies were noticed within the caliber, discoid
in shape, homogeneous and somewhat plicated, probably newly formed red

Fig. .ST 7.

■New Formation of an Artery in Decidua
Catamenialis.

D, ileeitlua elements, at their periphery traiisformert to basis-substance, the nucleus un-
chaufretl; .S", spiiidle-sliaped corpuscles, indicating the formation of an adventitial coat; A,
shininff, homoseueous elements in lonjritiidinal section, the forming smooth muscles ; the
i'udotlielia visible In the depth. JIagnitied 1000 diameters.

"blood-corpuscles. In this stage of development, both the endothelial and
muscular coat could be discerned in longitudinal and transverse sections of
the vessels.

Of the existence of newly formed veins there could be no doubt, and some
of them were filled with blood. These vessels were composed of an inner
endothelial and an outer fibrous coat, the latter made up of fine fusiform
bodies in longitudinal arrangement. Whether these formations could prop-
erly be considered smooth muscle-fibers, I am unable to decide.

836 THE FEMALE GENITAL TRACT.

The case furnished V)v Dr. Munde was the fifth. He gave a history of a
patient of his, a man-ied lady, who menstruated only at intervals of three
months, and who cast off decidual formations at everj' menstrual period. In
microscopical examination of this case, it was seen that most of the medullary
corpuscles were large and oval in shape. The fields of myxomatous basis-
substance were abundant, and often hokling in their midst coarsely granu-
lated nuclei. The formation of a fibrous reticulum around the nucleated
myxomatous fields and around the medullary corpuscles was more advanced
than in any other case. In all sections obtained from these specimens I met
with fields of tissue, consisting either of medullary elements or fibrous con-
nective tissue, in which a peculiar change had taken place, into a shining,
homogeneous mass, such as has been described as waxy degeneration. Capil-
laries and veins were also abundant, the latter bemg frequently engorged
with blood, but no arteries could positively be distinguished. These features
are not fuUy analogous to those of deeidua reflexa or vera ; and, from what I
have observed, I should conclude, therefore, that the case was one of deeidua
catamenialis unusually far advanced in development, and almost approaching
the featui'es of deeidua vera.

A positive discrimination between deeidua menstrualis and deeidua vera,
in their earliest stages of formation, seems to be a matter of impossibility, as
they have featui-es in common. The development of fibrous connective tissue,
as a rule, is farther advanced in deeidua vera than in deeidua catamenialis.
Deeidua vera, in its early stages — that is, up to the sixth or eighth week —
is always characterized by the presence of a mj-xomatous structure uniformly
distributed throughout the formation. Its circiilar or oblong spaces con-
tain either large, finely gi-anular plastids, with one or two nuclei, or a pale,
indistinctly gi'anular myxomatous basis-substance, in the center of which
often an unchanged nucleus is visible. Not infrequently, in deeidua vera,
we meet with multinuelear bodies, whose significance is shown by Dr. J. W.
Frankl. Finally, deeidua vera is marked by the presence of villosities,
which, running in all directions, are seen in longitudinal, transverse, and
oblique sections.

Literature. According to H. Kuudrat and G. J. Engelmann,* the hj-per-
trophied mucosa of the uterus, during menstruation, overlaps the openings of
the glands, with a marked increase of the size of the latter. The condition of
rest of the uterus during the period of reproduction is of but short duration .
as the mucosa commences to swell slowly before the menstruation, and slowly
returns to rest after it. No new formation of blood-vessels could be observed
in the mucosa of the uterus, swelled and hypertrophied in menstniation, but
a considerable opacity and fatty degeneration of the cells takes place. The
siu"face epithelium is preserved to the time of the fatty metamorphosis, but
when this ensues, the epithelium of the mucosa, as well as that of the glands,
is cast off to a considerable extent. In the first weeks of pregnancy, the
mucosa — especially the inter-glandular tissue of the upper layers — develops
to deeidua, and the glands become elongated and enlarged.

G. Leopold t draws attention to the difference between membranaceous
formations fi'om the uterus and those from the vagina. The former are cov-
ered by columnar epithelia, and contain the characteristic glands, while the

* " Untersuchungen iiber die Utems-SclileimUaut." Wiener M«'(liz. Jaiirbiicliei-, 1873.
t " Dj'smenorrhcea ilembranacea." Arcliiv f. Gyuakologie, 187(>.

THE FEMALE (iHMTAL Th'ACT. 837

hitter show only flat <'i»itlielia. He ))elievos iiieinhniiious (lysineiiorrha'a
tlei)eii<ls ui)oii a tliscused eoiulition of the uterus, sucli as chronic metritis,
fibrous tumors, or disphicemciits. He says tlie tissue between the tubular
phimls consists of small, polyhedral or f^lobular cells whose nuclei almost till
the bodies. Between these cells he found clusters of small, f^lobular lymph-
corpuscles. Evidently, he does not consider these cells to Ite <iecidual forma-
tions. He also found a few waving arteries in the midst of the membrane,
and a j^'eat many cajiillaries close beneath the surface epithelia, where the
hemorrhaj^ic clots are situated. He agrees with Beigel in terming this condi-
tion chronic endometritis and endocolpitis exfoliativa.

J. Hoggan and F. E. Hoggaii * draw attention to the difference between
membranes cast off from the uterus and those from the vagina. In the for-
mer, utncular glands were present, and around them, in a transparent matrix
or intercellular substance, embryonal cells in different stages of development
were noticed. These writers also call attention to the presence of embryonal
tissue below the epithelia of the normal uterus, which they consider to be
morphologically identical with that of true decidua, as well as that of the dys-
menorrho-ic membrane.

Wydert asserts that, in menstruation, the superficial layers of the mucosa
are cast off, whereas the deep layers remain intact. A distinguishing feature
between decidua vera and menstrualis is that, in the latter, the inter-glandular
cells are small, round cells, almost completely filled by the nucleus, while in
the former, the nucleus, in comparison with the i)rotoplasm, remains small.
He considers dysmenorrhoea membranacea (1) as a fibrous coagulura, (2) as a
mucosa altered by endometritis, and (.'5) as a decidua of pregnancy.

The residts of my studies of the structure of decidual formations are the
following :

1. Decidua menstrualis is formed by meduUnrij or embryomd eorpnscles, exhib-
iting a grctdiml development from a shining, globular, homogeneous mass of tiring
matter into nucleated jilastids.

2. Basis-substance, in decidua menstrualis, is ahraijs scanty. It may appear
either in the mysomatous or fibrous varieties. In the former, it is slightly granu-
lar and apparently structureless ; in the latter, it is either reticular or arranged in
fibrous bundles. Both kinds of basis-stibstance are formations springing from the
original medullary corpuscles.

3. Decidua catamenialis is traversed by a large member of blood-vessels, mostly
capillaries. In some cases there is also a distinct new growth of arteries in such
quantities as to greatly exceed the capillaries. Frequently, also, the formation of
veins occurs.

4. Decidua catamenialis always contains glands of the tubular variety, lined
by columnar ciliated epithelia. Very probably, these glands are not new forma-
tions, but simply the remains of the original utricular glands.

5. Decidua reflexa is composed of large medullary corpuscles, mostly of oral
shape. The formation of a myxomatous and fibrous basis-substance is much
further adranced, and the amount of venous blood-vessels much greater than in

decidua catamenialis.

6. Decidua vera is made up of a freely vascularized and fully developed myxo-

* " Patliology anil Therapy of Dysmeuon-licea Membranacea." Arclilv fiir Gynakologie,
1876.

t " Beitrage zur normaleu unil patholog. Auatomie der menscbl. Uterus-ScUleimhaut.
Arcliiv. f. Gynakologie, B<1. xiii.

838 THE FEMALE GENITAL TRACT.

inaton.s reticulum, in the meshes of which lie the nucleated flecidnal elements, or the
myxomatous basis-substance holds the remnants of the decidual corjtuscles. Fibrous
connective tissue occurs mostbj around the laryer blood-vessels. Decidua vera is
further characterized by the presence of villosities in different stages of develop-
ment.

(4) The Vagina and External Oenitah. The mucosa of the
vagina is raised in folds (rugae), and in this situation papillae are
present, while in the furrows between the folds the papillae are
small or absent. The papilla are simple throughout the mucosa,,
but compound at the height of the rugae and toward the vestibu-
lum. The loose connective tissue in the deepest portions of the
mucosa is dense, and somewhat looser in the outer layers. In the
mucosa, varying numbers of lymph-corpuscles are found, ar-
ranged sometimes in circumscriljed follicular formations. The
covering epithelium is stratified, blending with that of the cervi-
cal portion of the uterus ; no glands are present. The muscles
are arranged in external and internal longitudinal and middle
circular bundles, united by numerous fibers running in oblique
directions ; they are more developed in the posterior than in the
anterior wall of the vagina. The outermost layers are composed
of coarse bundles of connective tissue, with numerous elastic
fibers. Blood- and honph-vessels produce plexuses above the
epithelial cover and below the muscle-layers, which themselves
hold a large number of veins.

In the vestibuliun the mucosa contains small, acinous, mucous
glands, which are more numerous around the opening of the
urethra and on the clitoris. The Bartholinian glands are also
larger mucous glands. The hymen is a reduplication of the
vaginal mucosa, sometimes very rich in blood-vessels and nerves.
The labia minora are characterized by the presence of numerous
sebaceous glands, which are absent in new-bom children ; their
covering epithelium approaches the nature of the epidermis,
since the innermost scales are destitute of nuclei. The transition
of the mucosa into the external skin is completed on the labia
majora, which are rich in smooth muscles and fat. The clitoris
is covered by a mucosa, which, especially on the glaus, is amply
provided with tactile corpuscles and nerve-bulbs. The construc-
tion of its cavernous bodies is similar to those of the penis. C.
Grussenbauer, after careful study, states that the nymphae have a
delicate, cavernous vascular system. The erectile tissue of the
clitoris, according to him, is supplied with blood by small arter-
ies at the root of the clitoris directly, and by arterioles and a

Till-: IKMAI.E (ii:SII.\L IKACT. 839

capilliiry net-work at tlu* surfact' of the cavernous Ixxlics, indi-
rectly. The bull) of the vestibule is of tlie same structure as the
cavernous Ixulies of the clitoi'is.

The phtcndd <ui(l the iinihi/irtil cord have bc'i subjects of
research in my hiboratory, both as to their development and nor-
uuil condition and their patholou'lcal chan<»"es. Some of the stud-
ies arc not yet completed. The results of some investigations
are laid down in the two followiiii;- ai'ti(des.

A Contribution' to thk History of the I)p:vi:lopmext o?' the
Human Decidua. By J. W. Fraxkl, M. D., New York.*

It is acknowledged that the i)lac'cnta represents a connective-tissue forma-
tion belonging to the myxomatous variety. Formerly some histologists
(Friedlilnder and others) were of tlie opinion that epithelial elements enter
into tlie construction of the placenta ; but since the publications of G. J.
Engelmann and Hanns Kundrat, and recently of Gerhard Leopold, this view
can no longer be maintained, and, with the exceptioTi of the epithelial cover-
ing of the villi of the placenta, we now scarcely look for epithelial bodies in
the stroma, either in its villous or solid part.

The development of the placenta in its minutest elements has so far been
very little studied. We know, since the publication of W. Reitzt, that the
villi are originally solid masses, without any differentiation into stroma,
blood-vessels, and covering epithelium, which differentiation they present
only with the advancing growth of the embryo. Indeed, it is easy to satisfy
one's self about the correctness of the assertions of Reitz on growing
placentas of the second, third, and fourth months, where formed villosities
are already to be seen, beset with more or less distinctly pediculated buds of
a uniform structure. But how the solid part of the placenta, that nearest to
the amnion, advances in growth, especially the formation of the myxomatous
basis-substance, has not yet been elucidated.

Engelmann and Kundrat t described the peculiar clusters of large deeidua-
cells occurring in the growing decidua-layer of the placenta. They consider
these clusters as being in connection with the development of the villi.

Gerhard Leopold 6 repeatedly mentions their presence, and suggests that
these clusters, as he asserts, most numerous in the fifth month of develop-
ment of the placenta, are split into smaller and larger cells. How this is
done he does not say.-

George Hoggan and Frances Elizabeth Hoggan || also conclude that the
large, so-called embryonic multinuclear " decidua-cells " give rise to the
fonnative cells of the decidua, but they do not specify their view, nor
describe the way in which the latter originate from the former.

* Abstract of the author's paiier. American Journal of Obstetrics and Diseases of Women
and Children, vol. xi., October, 1S78.

t " Sitziinjrsbericlite der Kais. Akail. d. Wisseuscliaftcn in Wieii," Bd. Ivii.

t " Untersiichiiiiifi'ii iiber d. Utcius-Schleiinliaiit.'' WieiuT nicdiz. .lalirbiiclier. 1873.

i " Die UterHs-Sclileiinhaut wiihrend der Schwangerschaft iiiid der liaii dcr Placenta."
Arch. t. Gynakologie, ii. Tli., Bd. xi.

H "Znr Patliologie u. Tlierapie d. Dysmenorrhcea membranacea." Arch. f. Gynakologie,
H<\. X.

840 THE FEMALE GENITAL TRACT.

In the gi'owing placenta we always meet in the decidua-layer with multi-
nuclear masses, sharply marked from the surrounding myxomatous basis-
substance. These clusters are numerous in earlier stages of the developing
placenta, where f.ie decidua itself is only of a relatively small diameter ;
while the fully uoveloped placenta, in its solid part, is of a noticeable width,
but altogether devoid of the clusters above mentioned. On the contrary,
single elements, surrounded by the net-work of the myxomatous connective
tissue, are present only in a comparatively small number in the growing
decidua, while they constitute the whole solid part of the fully developed
placenta. This fact led the authors to the conclusion that the isolated
decidua-elements originate from multinuclear clusters.

The only way to examine a placenta, in my opinion, is to cut the tissue
with a razor after it has been sufficiently hardened by a repeatedly changed
one-half per cent, chromic acid solution. I cannot- advocate the picking
method of the \'illous portion, and still less, of course, that of the decidua.
By cutting we oftentimes succeed in obtaining thin sections of the villosities
in different directions, perfectly fit for examination even by the highest
powers of the microscope. Such sections are easily made through the solid
part of the i^lacenta ; while picking will always bring to view debris of the
tissue only, as a rule mangled to such an extent that a close examination
under the microscope is a matter of impossibility.

Specimens obtained from the solid part of a placenta of the six months'
development, with a power of about .500 diameters, show a great number of
bioplasson formations, partly built up by large nucleated elements, partly by
a uniform granular mass, in which there are imbedded nuclei in a more or less
var3'ing number. Besides, we meet with clusters, in which nuclei cannot be.
recognized, but a differentiation into smaller granular spindle-shaped ele-
ments can be traced out. These masses, as a rule, are distinctly bounded
toward the surrounding myxomatous basis-substance, which, owing to its
apparently homogeneous, highly refracting structure, is a well-defined forma-
tion. The net-work of the myxomatous connective tissue is partly loose and
delicate, including in almost every mesh a granular plastid, this being either
provided with or devoid of a nucleus, while in other places the myxomatous
net-work is very heavy, its meshes being narrow and filled with a light,
apparently homogeneous, structureless-looking substance. A still higher
development of the connective tissue can be found oidy around the arteries,
the adventitia of which is a combination of myxomatous with fibrous connec-
tive tissue, inasmuch as bundles of delicate fibers form an elongated net-work,
and in the meshes of these again granular, partly nucleated plastids are
visible. The veins, on the contrary, being sinuous and irregular in their out-
lines in a hardened specimen, are directly surrounded by loose myxomatous
connective tissue.

Sections made through the solid part of a placenta of nine months, if seen
with a power of 500 diameters, show the complete absence of clusters, the
"giant-cells" of the authors, and the whole tissue is decidedly myxomatous
in structure. The meshes of this tissue are partly filled with single, chiefly
nucleated plastids, many of which, owing to the prevalent amount of basis-
substance, are very narrow, and contain a light, apparently structureless
substance. Besides, a considerable amount of fibrous tissue is to be seen
principally in the neighborhood of ai'teries, the adventitia of which is alto-
gether fibrous in structure. Where several arteries run through the stroma

/•///•; I' i: MALE dEMTM. TliACT.

841

near each othti-, tlif .Klvcntitiitl layer, eoimnou to all, consists mainly of
fibrous struct iiir. hiiwccii whidi relatively small bridj^es of myxomatous
tissue are left.

Let us now cxatiiinc tlif t'oiiiiatioiis in tlic soliil ])art of the placenta with
the mafjnifyiuf^ ])ower of 1 '_'(»(> (ilMinctci's, Ix'^^iniiiMic with a six-months'
placenta. (See Fif?. ;{7s.)

The stronui is l)uilt up by l)i()])lasson, arranged in the sliajx'of multinuelear
bodies, and by the l)asis-substance. The latter, lookin-; homoj^eneous or
finely <,'ranular with a low jiower, proves to be formed Ijy extremely small
spindles closely packed toifether, if seen with a high power. Tliese spimlles
are united with each other by delicate threads running vertically through
all the trabecular of the basis-substance. In the meshes of the reticular
basis-sub.^tance, again, we tind mujid or oblong plastids.

Jfw

Fig. 378.— Human Placenta of Six Months.

-V, multinuelear biopla.ssoii cluster ; C, delliate fibrous conuective tissue; />. plastids iu
transition to a myxomatous basis-sulistauco. Magnitied 1200 diameters.

Wherever we meet with bioplassou, its structure, as fii-st described by C.
Heitzmann, is plainly visible. Coarse granules present in the middle of
nuclei, the so-called nucleoli, send out radiated spokes, through which they
are united with the neighboring smaller granules. Again, these granules are
united with each other and with the shell of the nucleus by means of delicate
threads. The shell of the nucleus, being either a smooth or granular layer,
although continuous under all circumstances, projects very minute radiated
oflfshoots, which traverse the light seam around the nucleus, and run to the
next gi-anules of the bioplasson body. All gi-anules of the latter are united
more or less distinctly by fine threads, so much so that a delicate net-work
is established throughout the corpuscles. Where bioplassou meets with

842 THE FEMALE GENITAL TliACT.

basis-substance, we always see numerous fine threads projecting into the
basis-suVistance, where they are lost to sight.

In the fully developed deeidua the details in the structure are exactly the
same as in the growing placenta, with one exception — y\z. : that multinuclear
masses are absent ; the meshes of the myxomatous basis-substance contain-
ing roundish plastids, mainly devoid of nuclei, while numerous meshes, sur-
rounded by a dense, highly refracting net-work of the basis-substance, look
homogeneous and structiu-eless. The basis-substauce assumes, in the adven-
titial layer of the arteries, a decidedly fibrous structure, which again proves
to be constructed by bundles of minute spindles, in the narrow and elongated
meshes of which granular bioplasson is to be seen. The interstices between
these spindles of the fibrous basis-substance are also traversed by minute ver-
tical threads.

The history of the development of the basis-substance has always been a
matter of careful study with om* best histologists. Now, the placenta offers
an excellent means of settling several points of discussion, both on account
of the relatively short time required for its formation, and the clearness of the
relation between the protoplasm and the myxomatous basis-substance.

The manner of formation of the myxomatous basis-substance of the pla-
centa is as follows :

The formative elements appear in the shape of multinulear bodies, exactly
like those in developing bone or cartilage where the so-called "giant-cells "
prove to be the forerunners of the forming basis-substance. The next step is
the formation of bioplasson layers, in which nuclei are no more recognizable,
v,-hile the net-work of living matter is arranged mainly in a longitudinal direc-
tion— xiz.: in the shape of closely packed spindles. In the next stage the
fluid part of the plastids is transformed, chemically, into a shining, highly
refracting basis-substance which hides the living matter, this being demon-
strable only in the interstices between the delicate spindles in the shape of
minute grayish threads.

The most solid part of the basis-substance, as represented by the fibrous
tissue of the adventitia of the arteries, originates in the same way as the
myxomatous basis-substance of the stroma of the deeidua. The only differ-
ence is that the gi-oups, respectively the net-work of the living matter, are
more elongated in the adventitial fibrous than in the mj-xomatous reticular
tissue. In both instances the meshes hold a certain amount of unchanged
bioplasson, which is relatively profuse in the myxomatous tissue and scant in
the fibrous. Even in the latter tissue we find larger and more niunerous bio-
plasson masses in the deeidua of the placenta, advanced only to the fifth or
sixth month of development, than in the deeidua fully ripe for elimination
from the maternal bodv.

Waxy Degeneration of the Placenta. By Jeannette
B. Greene, M. D., Xew-York.*

My attention was drawn by Dr. Heitzmann to the fact that specimens of
placenta from cases of premature birth and abortion, which liad been pre-
sented to him by ilifferent physicians, exhibited peculiar changes in their

* Abstract of the author's essaj'. American Journal of Oi'ntetrics and Dineases of Women
and Children, vol. xiii., 18S0.

THE FKMALK (il'lSlTAL TUAl'T. 841^

stnietiiro. Altliongli to tlu« iiukod eye these appearanc-es resemble those of
fatty deKeneratiou, tlie mieroscope showed the morbid eondition to Ije lliat of
waxy rather than fatty (h'f^eiieration.

Tlie subject appeared to be of sufliciciil interest to bestow a few weeks
upon its iiivestifjatinii. I had at my disposal ten placentie of tin- foliowinf^
ages :

First. A phu-enta of six or seven weeks, fu'tus attached. Tliis j)lacenta
was a solid, clumsy-lookinf^ mass. Its snV)stanoe had in sonu^ i)laces been
entirely transformed into a <^rayish-yeilow material, of a shininj; apjx'arance;
in other parts the shiiunt^ material appeared only in scattered foci.

Srroiid. A three-months' placenta, which hail been detached from the uter-
ine wall six weeks after abortion, a severe Inemorrhage havinfj; occurre<l. In
this placenta there was no perceptible change to the naked eye. To the touch
the mass appeared rather denser than nornnil placental tissue.

Third. A four-months' placenta. A portion of this placenta, with the-
umbilical cord attached, came under my observation. This specimen exhib-
ited the same general characteristics as the others — the same yellowish
patches scattered throughout the placenta. The decidual portion had been
extensively invaded by a yellowish material, varying greatly in width in dif-
ferent parts. Tiie amniotic surface had a mottled appearance and was deeply
corrugated.

Fourth. A five-months' placenta, together with the foetus. This specimen,
normal in its main mass, showed in the decidual portion small, homogeneous
patches of a yellow color, and in the villous portion scattered points, also of
a yellowish color.

Fifth. A flesh mole, fifth month of pregnancy. This specimen was a mass
about the size of the ftt'tal head at terra. It was irregularly lobed, and con-
sisted principally of haMnorrhagie clots. Within the tissues on the periphery,
and between the clots, remains of the decidua were to be seen, of a grayish-
yellow color. The foetus was lost.

Sixth. A six months' placenta. Sevei-al microscopical specimens were sent
to the laboratory for examination. These specimens exliibited the same gen-
eral characteristics ol)served in the other cases.

•Serenth. A placenta of seven months. The whole placenta was paler than
normal, and the entire tissue, both decidual and villous, presented a decidedly
glistening and lardaeeous appearance. There were no isolated spots of
degeneration. The attached cord was somewhat cedematous. The cross-sec-
tion presented the same lardaeeous appearance observed in the placenta.

Eitjhth. A seven-months' placenta. This placenta was coarsely lobulated,
and of a consistency and thickness gi-eater than normal. The entire tissue,
but chiefly the decidual portion, was of a yellow color, greatly resembling fat
in appearance. The umbilical cord presented no changes of any kind. Foetus
died soon after delivery.

Xiiith. A placenta of eight months. There was no change in the vdllous
portion, and in the decidual portion only an occasional spot of yellowisli dis-
coloration. P^oetus lived.

Tenth. An eight-months' placenta. The decidual portion presented a lar-
daeeous appearance ; the remaining tissues were normal. Foetus living at
birth.

In all cases in which the yellow discoloration was apparent, the diagnosis
made without the aid of the microscope was fatty degeneration of the pla-

844 THE FEMALE GENITAL TBACT.

«enta. For many years this condition was thonglit to have been the principal
cause of abortion or premature birth, resulting in tlie death of the foetus,
either within the uterus or soon after delivery.

Altliough the fQ?tus might have the appearance of being well developed,
its death, as a rule, occurred whenever the degeneration in the placenta was
ol>servable. In many instances the miscarriage was habitual, taking place at
about the same period of pregnancy ; the foetus never being perfectly devel-
oped.

The ten placentae above described were furnished either in a fresh condi-
tion or preserved in alcohol. All these placentae were placed in a half per
cent, watery solution of chromic acid for hardening.

Specimens obtained from placentae which had undergone a high degi-ee of
degeneration — Cases one, three, and eight — exhibited with the lower power
of the microscope the following appearances : the decidual tissue contained
sharply defined patches of a grayish or yellow color with a peculiar luster.
These patches were of a uniform structiu'e, with only a slight trace of decidual
tissue remaining, and they were built up by irregular, jagged globules closely
crowded together, strongly resembling fat in color and in general appearance.
Toward the decidua these morbid spots were in some places distinctly defined,
in other places were bounded by tissues, in which the morbid change was of
a less marked degree.

In the villosities the degenerative change is rarely found, but, if found, it
is, as a rule, only in the parts in immediate connection witli the decidua. In
those rare instances where the degeneration did occur, it was not found to
pass beyond the reticular or homogeneous stage — that is, it did not lead to
the transformation of the mj'xomatous tissue into globular clusters.

The decidual portion of the three placentae, which exhibited the highest
degi'ee of the homogeneous degeneration, showed also a greater development
of fibrous connective tissue than is to be foimd in the normal placenta of the
same age.

Within the fibrous, and also within the myxomatous basis-substance,
but in a lower degi'ee, the oblong decidual elements showed a coarse granula-
tion, so as to entirely conceal the central nucleus. The gi-anules resembled
fat in their high degi-ee of refractive power. In the villosities, those which
had an unchanged myxomatous structure showed the normal amount of
blood-vessels and capillaries ; while in those ^dllosities, in which the homo-
geneous degeneration was marked, scarcely any trace of blood-vessels was to
be found. ^

Higher powers of the microscope, five hundi-ed to six hundred, showed a
homogeneous change of the basis-substance, with coarsely granular plastids,
almost unchanged. A slight formation of connective tissue was observable
encircling the villosities, and irregularly scattered between and within them;
in the latter position, however, barely traceable. This tissue showed small
plastids with nuclei, also apertures, indicating the caliber of former capil-
laries. The gi'eater part of these vessels, had, however, entirely disappeared.

A power of twelve hundred immersion plainly revealed the nature of the
morbid change. The basis-substance was divided into irregular fields of
shining appearance ; between these fields the bioplasson was unaltered,
exhibiting its characteristic, net-like structure. (See Fig. 379.)

This reticulum was also traceable within the fields ; here, however, the
meshes were larger than those in the unchanged portions. This net-like

////•; I'KMM.I-: (H-.MIAL tuact.

845

stnutinv (lisappciirs altO}:Ct'thi'r only in tla- lii^^hc'st ilo^i'i''' <><' tin- dcKeiifra-
tioii, wlioro iiothiu{? is to be soen but shining, structiirt'leHH muHseH, with
high refrai'ting powor. Tlie bases of the villosities are either of the same
structure as tlie deeiihia, or they show a slightly fibrous basis-substance
iutersperseil with plastids. Xo blood-vessels can be traced in this part. In
some villosities irregular openings are observable, evidently the remains of
capillary blood-vessels, which, in tlie degenerative condition, serve only for
the passage of plasma, and not for the circulation of the blood-corpuscles.
The ([uestion arose : What was the nature of this degeneration f
In order to settle this inquiry, a number of reagents were employed. Aii
ammoniavdl ftolntion of cdniiinc changed the homogeneous masses in the basis-
substance only in si)ecimens where the degeneration had not reached a high

^'^^'i^m<\r^\j:^ A ^■A:;f^;^i

■«v''-

f;)- ■■:

Fig. 37l». — Waxy Degeneration of the Placenta.

T, (Icridnal tissue in a liifrli degix-e of waxy nietainoritliosis ; V, basis of a viUns witli
clefts, probably the remain's of vessels : F, basis of a villus with fibrous basis-substance ; B,
basis of a villus in a high degree of waxy metamorphosis. Magnified 1200 diameters.

degree, and which had not been kept any length of time in chromic acid
solution ; in the latter the homogeneous masses took on a yellow, almost a
gi'een color, and were imaflfected by the carmine. Carmine is, therefore, an
excellent reagent for bringing into \'iew the homogeneous fields, as the car-
mine readily stains the normal i)ortions of the tissue. The shining granules
in the decidual elements also remain unchanged. The carmine-stained speci-
mens were left in absolute alcohol for a short time — twenty-four hoiu-s ;
they were then dipped in oil of cloves, retiu'ned to the alcohol for a short
time, and finally placed in water for mounting in glycerine. In these speei-

846 THE FEMALE GENITAL THACT.

mens, the homogeneous fields and clusters, even in the highest degree of the
degeneration, remained perfectly unchanged. Those decidual elements which
had before shown coarse, shining granules, after treatment with oil of cloves,
lost in a great measure their granular appearance ; clearing up to such an
•extent that the reticular structure of the bioplasson became again visible
with the highest powers of the microscope. A few of the granules in these
specimens, however, showetl a lower refracting power than fat. Such
granules were also found in the connective tissue, joined to the neighbor-
ing net of li\n[ng matter by means of fine threads. Specimens stained with
carmine, taken from the alcohol and placed in spirit of tm-pentine, showed
the same results as after treatment with oil of cloves.

After having thoroughly washed the specimens in distilled water to
remove the chromic acid stain, a half per cent, solution of cJiloride of (/old
was applied for one hour, and they were then removed. After a few days
the normal basis-substance exhibited a slight purple color. The homogene-
ous fields and clusters took on a dark-blue tint, which became deeper after
exposure to the sunlight. The coarse granules in the decidual elements did
not change their color.

On application of tincture iodine, the homogeneous fields became tinged
with a brown color. The addition of sulphuric acid^ produced no effect upon
this coloration.

Fiidtsine, in a concentrated solution, gave a darker hue to the homogene-
ous fields than it did to the normal basis-substance. Dark crimson globules
were scattered through the decidual elements, which gave a beautifully
spotted appearance to the specimen.

Violet methyl aniline, in strong solution, stained the normal tissue a dark
blue color, at the same time giving to the homogeneous fields a reddish hue,
which varied in intensity according to the degree of morbid change — being
■darker where the degeneration was most strongly marked. This red color
was most noticeable with low powers of the microscope.

Osniic acid, in a one per cent, solution, stained the whole specimen brown.
The homogeneous fields and strings, in many places, did not differ in their
color from the adjacent tissues, while in other parts they had assumed a
darker hue. The shining granules scattered in the decidual elements, through
this re-agent became very dark brown — almost black.

Picrate of indiyo gave to the specimens a uniform light green color ; the
homogeneous fields and strings were stained a deep grass-green.

From the above observations and experiments it follows that, in all
the placentae here described, a peculiar change had taken place in the
basis-substance of the placental tissue, which change bears a close resem-
"blance, in all essential characteristics, to waxy degeneration as it occurs
in other organs. In a few placentae only was there a fatty change in the
decidual elements, and this change certainly was of much less extent than
the waxy degeneration.

Waxy degeneration is obviously a morbid chemical change of the myxo-
matous basis-substance. The nature of this change is almost unknown,
although its analysis has been attempted by very good chemists. The asser-
tion that it is de-alkalized fibrine is merely hypothesis. The net-work of li\dng
matter is preserved to a certain extent, except in cases where the waxy degen-
eration is in its most advanced stage. In these cases the reticulum of living
matter appears completely lost.

rill': I' i: Mali: aEsiiAL iuact. h47

Whili' tlu' waxy (Icj^fiicratioii is located in tin- l)asis-sul)Htaiic(' only, the
fatty (lefj;tMU'ration, on thf contrary, is found uhnost cxcluHivcly in the living
nnittcr. With hij^li jxiwi'rs of tin- microscope we j)laiidy see the granides of
livinj; matter witiiin the decidinil elements first increase in size, and {^a<lu-
ally takin;; the peculiar sliinin<; ai)pearance so characteristic of fat. At first
the shiniii;^ fat-<;ranules remain in unbroken connection with the ueiKlihoriiif;
reticulum of living mutter: afterward the granules apjjcar to be freed from
their union with the reticulum, and finally they coalesce and produce oil-
globules. Even in the highest degree of degeneration the living matter never
seems to be entirely lost. This is demonstrated by the treatment of the speci-
mens with oil of cloves or turpentine, all fat being destroyed by these re-
agents.

In nearly all decidual elements a scanty reticulum of living matter may be
traced, and in some parts with enlargements at the points of intersection ;
and in these enlargements coarse gi'anules are frequently seen.

The re-agents indicate that there must be a slight difference between the
waxy mass of the placenta and the waxy degeneration we find in the kidneys,
liver, and spleen. It appears that, in the above-mentioned organs, the chem-
ical change which takes place in the basis-substance differs somewhat from
that which takes place \n the placenta ; the difference, however, is too
insignificant to alter either the change itself or its results in the placental
tissue.

In placenta No. 7, the aiiniioii in those parts in immediate contact with
the decidua of the placenta, was affected with morbid changes identical with
those observed in the placenta itself. Scattered through the amnion were
shining, homogeneous bodies, also rod-like formations, which were in contin-
luty with the connective tissue of the amnion. The homogeneous bodies
were either round or oblong, showing a central nucleus, but by no means so
distinctly stratified as are the amylaceous corj)uscles of the arachnoid. It
may be that these forms are the remains of bioplasson bodies whose fluid has
been transformed into a waxy mass.

In the Kiiihilical cord of this placenta I observed a peculiar change starting
in the portion attached to the placenta and extending two or three inches.
In the periphery of the cord the mj-xomatous tissue was fully developed,
while the tissue in the vicinity of the umbilical arteries showed considerable
enlargement of its meshes — the so-called di-opsy of the cord. The meshes
Avere surrounded by extremely fine fibers, and crossed by a peculiar, shining,
yellow reticulum, inclosing empty spaces. In connection with the bundles of
fibers that surrounded the meshes, coarser or finer trabecula? were oVjserved,
which showed sliiniiig enlargements at the points where the tral)eculaB were
cut transversely. In some regions delicate, pediculated buds and club-like
projections, or rosary-like chains, were seen. These formations took up the
stain of fuchsine very readily, and were unaltered by treatment with turpen-
tine and alcohol. (See Fig. .380.)

It seems oMious, therefore, that this change of the umbilical cord which I
have studied is due to waxy degeneration of the reticulum of the mj-xoma-
tous tissue, together with liquefaction of the basis-substance.

The literature of the subject of my researches is extremely meagre.

Carl Kokitansky * mentions amyloid degeneration of the placenta, without
further details. He is the only observer who speaks of such a degeneration.

'-"Manual of Morbid Anatomy," chapter oii " Anomalies <if the Placenta." Vienna, 1861.

848

THE FEMALE GENITAL TRACT.

■ Carl "Wedl,* on page 1 70, says : " Tlie most striking morphological changes
are those whieli occur in connection with miscarriages from the sixtli to the
ninth month, when the foetus is dead. The most usual alteration consists in
an accumulation of a dark-yellowish or grayisli-brown molecular substance,
wliicli renders tlie villi, with their clavate extremities, almost opaque, or merely
diminishes their i)roper trausi)arency at this point. This metamorphosis of
the villi usually extends over entire groups, and it may be very strongly
marked in many parts of the placenta, while in others it is very faintly indi-
cated or entirely absent. It is more developed on the convex than on the
concave sides of the placenta, and is associated with an absence of blood in
the affected portions." On page 171, he says: "The degi'ee to which the
atrophy has advanced may be estimated by the extent to which this kind of

T, trabccahL- of the myxomatous tissue ; B, knob-like projections. Magnified 1200 lUani-
eters.

metamorphosis can be traced toward the thicker stem of the villi. The con-
nective-tissue elements of the stem are frequently in a state of fatty degener-
ation— that is to say, brilliant molecules of considerable size are visible in
the fiber-cells, from which the nucleus has escaped — or a chain of fatty
molecules may be seen in the more slender fusiform fibers."

Carl Hennig t speaks of fatty degeneration of the decidua vera in the

"•"Rudiments of Pathological Histology." London, 1853.

t "Studieniiberden Bau der menschl. riaceuta uuduber ihi- Kikiaukou." Leiiizig, 18(32 ;
Sclimidfs Jalirb., 1873.

rilF. Fh'.MM.F. dFNITAI. TliACT. H45)

last inontlis of prcf^iuiiH-v. Morljid, fatly deKoiioratioii occurs, a«'<'or(liii^ to
this writer, in tlic vera scrotiiia |»lacciita', often also in tins villi ; in jicrsonsof
impaired health, this dej^eneration acconi])anios iiiHannnation of the placenta,
the vesionlar mole, and syphilis; tlu^ result In-i^ij,^ sihoi-lion nv ])7Tniuture
birtli. No allusion is made to amyloid defxeiiciatidii.

The conclusions drawn from the examination of the ten placentie are:

First. Tlntt th<- cliaiiiic in ihr jihia-nld so jir<i<hirlir<- ofalxtrtion ami iirniiatiirr
birth is a ivaji/, and not a Jufti/ tict/ini ration, as hiri'lojorf believed.

Second. Amonti the ten i>laeentw in irajj/ det/en<ration, three only, in the
hit/hest det/ree of this morbid ehani/e, e.vhil>ited sit/ns of fatti/ det/eneration. also,
and this latter eondition iras (dirays much less marked than the former.

Third. The waxy deifenrration consists in a jiecidiar chemical alteration in the
myxomatous Ixisis-snbstanee, both in the solid and the villous portions of the
placenta.

Fourth. The dei/eneration is kindred to Ihal ivhich occurs in the liver, spleen,
and kidneys of .so-cnlted dyseratic or cachectic individnats. The plasfids of the
dccidna and the villosilies also enter the waxy det/eneration in their fluid portion.
The net-work of living matlir is not affected by this chantje, exeejtt in its hi</her
deijrccs, where the livinn matter completely disapjiears.

Fifth. Fatty dcj/eneration resnl Is from a chemical chanye of the living matter
at the }>oints of intersection of the net-work — the so-called (jrannles. At first the
fat-yrannlcs are joined to the neiyhboriny reticnlnm by means of fine threads;
afterward, the fat-y ran nles coalesce and prodnce fat-ylobnles.

Sixth, flaxy deyeneration of the placenta is sometimes combined with an
analogous deyeneration of the amnion and the umbilical cord. In the cord it
appears in the fortli of a shining reticulum arising from the degeneration of the
fibrous net-work of the myxomtiious Ixisis-siihsttince.

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