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Full text of "A text-book of anatomy"

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AUTHORS. 

BEVAN. ARTHUR DEAN. 
GERRISH. FREDERIC HENRY. 
KEILLER, WILLIAM. 
McMURRICH, JAMES PLAYFAIR. 
STEWART, GEORGE DAVID, 
WOOLSEY, GEORGE. ' 



[EXT-BOOK OF ANATOMY 



BY 



^MERIC^^ A^TJTHORS. 



EDITED BY 

FREDERIC HENRY GERRISH, M. D., 

PKOrCSHIB OF ANITOHV IN THE MEDICAL SCHOOL OF MAIME, BOWUOlIt COLLBBI 



SECOND EDITION, REVISED AXD ENLARGED. 



ILLUSTRATED WITH 1003 ENGRAVINGS IN BLACK AND COLORS. 




LEA BROTHERS & CO., 

PHILADELPHIA AND NEW YORK. 
1902. 

3 



Slit«re<l accorillng to Act of Congrevs to the jcmr IWr^, by 

LEA BROTHERS & CO.. 

Ui tiK Oi&c« of Gbe Ubrarlftn of CoagreBs, at Wuhlngton. All riffhto refterred. 



VltTDOTT A THOHVdH 









PREFACE TO THE SECOND EDITION. 



Two vears have suBiced to exhaust the very large first edition of thia work, and 
have brouglit to those responsible for its existence an early ami gratifying sense of 
pn>fe»«ional approval. The test of success is comprehensive, and may be fairly 
construed its iiicUuliiig the execution of the book, about which misgivings were 
{Kirdunable, and iLs plan, uliout which there viia a rcaiioiiable degree of confidence. 
In tlieir work us teaeliers of anatomy the aiuliors had long felt the need of a text- 
Ixwk presenting the essential facts of human stnieture, and judiciouttly avoiding 
the unini|Mirtunt and exceptional. Between tlie extremes, represented on the one 
hand by jxKrket manuals, with tiieir tlavorlcss cinidcnsution, and on the other 
hand by eucyelo[>e<lias of universal inclusiveness, there is room for a work of 
convenient size, snflieient to contain in systematic array those portions of ana- 
tomical knowledge which are net^-asary to the intelligent study of phj-siology, 
surgery and internal me<lieine. The logical limits of this field excluded the much 
grejiter collection of facta having no known practical bearing, or only the rarest 
appii(Ution. 

The authors have unceasingly cntU'tivored to facilitate tlie work of both student 
and teaciier. Both are tested in every exanunntioii, and particularly in those con- 
ducted by State Lifei»>ing lioanls. Acconlingly, fnmi the vast a<«uniulations of 
anatonii<-al .science liinse i>ortions have Ix-eu selettitl which arc likely to be of 
actual service to the student in his subsetjuent study, and to the practitioner 
in his cliniwil work. Emphasis lias been laid upon the most imimrtant fiicts, 
oljsourities have Ix'cn clarified, the greatest amount of help has been given in the 
)>iirts which are most illHienlt to learn, and everything has been illnstrjited by all 
a\ailablc methods. In riliort no effort has Iteen spared to promote facility of 
acquisition and |x'nnaneni-(; of the knowlwlge gainetl. 

The ammgemeiit of the Iniok is along familiar lines, the ordinarj' divisions of 
systematic anatomy having been tbllowe<l in the main. Jjicli author has set f<)rth 
his subject in sncii manner as ex|)erlence has shown hini to be profitable. Great 
n'lative stress has been laid u|ion vis<'eral slrnctun', without neglect of other 
bnmehes; suriiice anatomy has reeeive<l attention more in pmjiortion to its use- 
t'ulncHs than is usual, and the picloriiil and diagninmiatie il lust rations (thanks to 
the remarkable liWnility of the publishi'rs) are phenomenally abundant and of 
striking artistic excellence. Wherever ]iractit«ble the names of the [wirts have 
\n-vn eugnivcil directly ii|)on them, a method wliich has tiic great advantage of 
conveying at a glance their slia|>c, position, extent and R'lations. 

It is l)clieve<I that the plan of giving directions for dissection in a se|iarate 
chajiter will prove a marked (iinvcuience to tbc student. 

Thes<- chanieteristies of the work may fairly be cretlited with its adoption in a 



-^ee-b 



ti PREFACE TO THE SECOND EDITION. 

large number of meilical schools, and its L'Xieiisi\f use l)y Mtudeiite and praoti- 
.tioiifrs on both sides of the Atluutie. The wirly opjKirtniiity for revision, cn-atcti 
by this di'mand, lias been faithfully utilized, every section having U'en critically 
examined for possible improvement. Such changes have been made as wciv ren- 
dered necessary by the progress of aiiutomieal science, and new matter hiis been 
added wherever desirable and consonant with the general scoi>c of tlie ivork. Par- 
ticular attinitiun lisis been bestowed upon relational anatomy. Instead of the 
schematic device previously employe*.! for showing the relations of the princl})al 
arteries, a series of horizontal soctioits at different levels lias iK-cn prepared, the 
various ]»arts l>eing lalH'Uecl directly with their names wherever leasihle. By this 
plan greater precision is attained, and tlie facts an- presented in u manner esjK- 
cially promotive of prompt com prehension an<l emluring retention. These same 
transections will be found equally useful in rcgiinl to the relations of other 
stnietures — nerves, muscles, etc. 

In matter of illustration, a nuni)>er tif figures have l>een replaced with others 
seemingly better udajited to their pur|)ose, and ne^^■ jiictures have In^en libi'rally 
added. The chapter on Osteology, for cxamjile, has Ixjen enriched i^ith a series 
of drawings displaying the areas of attachment of muscles to Ixmes, ivhicb should 
prove useful. The addition of new engravings brings the total alxive one 
thousand, a very lai^ proportion l>eing in two, three, or four colors. 

It is hoped that the improvements in this edition, of which a few have t>een 
raentione«l, will still fiirther increase the favor already Ix-stowed on the «<irk, 

F. H. G. 
Portland, Maixk. Se|ileiiiU;r, WWi. 



LIST OF AUTHORS. 



ABTHL'R DEAS BEVAK, M. D., 

Professor of Anatomy in Riusli Medical Collie in ajfiliation wiih the Vnivereitf of Chicago; 
Surgeon to the PreHbyleriun and St. Liike'a Hnapitalx, Chicofco, ele. 

FREDERIC HEXRY GERRISH, A. M., M. D.. 

Proffmor of Anatraiiy in liie Mediml Sfhoiil of Maine, Bovdoin Colle)^ ; CoDimlting Sur- 
geon lo the Maine tieiieral liospiinl, Portland; Kellow of the American Surreal Asaociation; 
sometime Pr«eident of the American Academy of Medicine, etc. 

WILLIAM KEILLER, F. E. C. S. (Ei.is.), 

Profewtor of Anatomy in tlie Medical l)e|)arlmenl of tlie L'nivereltr of Teias, Galveston : 

sometime Ix^cturer on Anatomy in the Kdiubnrgh Medical School, etc. 

JAMES PLAYFAIE McMURRICH, .^. M , Ph.D., 

Professor of Anatomy in the L'niveniily of Micliigan, Ann Arbor ; sometime Prufestior of 
Biology in the University of Ciocinnati nnd A««ociate Prore^«or of Animal Morphology in 
Clark I'liirersity, etc. 

GEORGE DAVID STKWABT, M. D. 

ProfcBsor of Anatomy in tlie University nnd Bellevue iroepkal Medical College, New York 
Cily ; Visiting Sutton lo Itellcvne ilwpilul, etc. 

GEOB(ii-: \V(k>i>i:y. a. n., m. d,, 

Profi'Hsor of .\natomy and Cliniml Siirgcri- in (he rnmell University Medioal College, Kew 
York < 'ity ; Visiting Surgeon lo Bellevuu Ilu«])ilal ; Felloiv of ihc .^inerinin Siirgiiiil Akso- 
rijiiiiin, elc. 



COISTTENTS. 



INTRODUCTORY. 



By F. H. Gbrri^h. 



VM-.T. 

Definition -, 17 

Names anil Delimitations of Surface Parts . 21 

The ^ysleniij of Organs and their Functions . 29 

Orf^ns removing Waste Matters ... 30 

Tlie Vascular Sj-stem 30 

Organs Supplying Nnurinhment .... 31 

Organs of Internal Secretion 32 



Organs of Motion 32 

Frameworli Organs 32 

Organs of Reliilion . . 32 

Organs of Keproduction 33 

The Order of Topics 33 

Methods of Study 33 



ELEMENTARY TISSUES. 



Bs F. H. Gerrish. 



Cells. 



Cell -reproduction 39 

Classib op Tibbubs. 

The Kpiihelial TissiiM 41 

The Mufitentacular Tissues to 

White Fibrous Tissue 46 

Yellow Fibrous Tiaiue ........ 47 

Areolar Tissue 47 

Adipo« Tiesiie 49 

(ieliilinouH Tissue 50 

.\denoid Keticiilor Tijwne 50 

Neun^lin .50 

t'artilaeiiious Tisnues .SI 

Oiweous TisHiie 52 

l>eniinat TJivue - . - 56 

The LirjUJil Tissues 57 

The J,vmph . 67 

The Biood 57 

The ^[uscular Tissues 58 

Plain Muscular Timue 58 



Croai-Htriped Muscular Tinue 59 

Cardiac Muscular Tissue 61 

The Nervous Tissues t!2 

Membkanes 64 

Serous Membranes 66 

SeroUd Membranes Fn^r ...... 68 

The Lining Membrane of the Vascular 

System 68 

The Lining Membrane of Certiiin Cav- 

ilies ill SiisCentiiL-ular Tji«>uie» .... 69 
Tlie Lining Membrane of tlie Cavity of 

the Cerebro-spinal Axis 69 

Synovinl Membranes , . . . 69 

Arlipiilar SynoTial Memlinnes .... TO 

Vaginnl Synovisl Membranes 70 

Burxal Synovial Membranes 71 

Mucons Membranes . 71 

Cutaneoua Membrane 74 

(iijixne 75 



EMBRYOLOGY. 



By J. P. McMiRHicH. 



."^permatodenesis 

< li^enesis 

The Early Stages of Development 

The I'nihilical Cord and the Placenta . . . 
Organs Derived from the Endodenn . . - 

Tlie Teeth and Salivary Olanda . . . . 

The Branchial ('lefts anil the Stnjftiircs 
[>erivp(l from (hem 

The Trocbt-a and Lungs 

The Inte^itine and Mi^wnleries . . 

The Liver and Pancn-as 



77 

83 [ 
86; 



87 
88 
8H 
90 



Organii Derived from the ^(e^'ode^m .... 91 

The Skeleton 91 

The H,'art ami Bh-xl-vesiel- . ... 93 

The r*iapiiragm . , . 97 

Tlie Lyiii]ihalic Ve»fieK the Spleen, and 

(be Suprnrenal ('ii[wides 98 

The Husftilnr System 98 

Tlie Kscretiiry and Bci mxh id ivr Organs 9S 

Organs Derived from the Ki-t<Klerni .... Ifl3 

Tlie.NervnusSvMcra 103 



9 



10 



CONTICNTS. 



THE BONES. 

By G. Wooi«ev, 



FAQI 

. 113 
. 115 



General CoiuideraiionH 

Tbk ^PINE . 

The Cei-vicol Group of Verlcbrw ... . 116 

The Thnracic Group of Vertehne 118 

The Lumbar Group of Vertebne .... 119 

The Sai^ral Vertebia 120 

TheCoccvi l-ii 

The Spine an n Whole Vli 

OsBifiolioii of the Vertebne 125 

The Thcikajc. 

The Sternum 127 

The Ribs 129 

The Ctntid fartilages 131 j 

The Thorau as a Wliole 131 ! 

Tbe Bone^ Of TBE Upput Limb. 

The Clavicle 133 

The Scapiiln 135 

The Humerus 13S 

The Ulna 142 

The Radius 144 

Tbe Carpal BoDiM 145 

The Scaphoid 146 

The Semilunar 146 

The Cuneiform 147 

The Pisiform 148 

The Trapezium 148 

The Trapezoid 119 

The Ob Magnum 150 

The Unciform 151 

The M^acarpal Boncx 151 

Tbe Fhalangfcs 152 

The Boves of the Lower Lihk. 

The Hip-bone 152 

Thellinm 1">3 

Tbe Ischium 155 

The Os PubU l-'i'! 

The Pelvia 157 

The Femur 159 

The Patella 163 



Tlie Tibia 

The KibuJa 

The Tarsal Bimeit 

Tbe Astrajtaliw 

The Calcuneuiii . . . . 

The Cuboid 

The Scaphoid 

The Cnnt-ifcinu 

The liiteiTial l.'(inei[(inTi 

The Middle (imeifonii 

The ExieruHl (-'iinciforiii 

Tbe Melatarsal Bones - 

The PhalanRCT 

The Fool an a Whole 

Hmnol<^e8 of the BoneH of llie Two 
Extremities 

The (fKrLL. 
Tht BotK» of the CivninM. 

Tlie Ocdpital BiHie 

The Parietal Bone 

The Frontal Bone 

Tlie Temporal Bone 

The Sphenoid Bore 

Tlie Ethmoid Bone 



16t> 

lIM 
1IM 
itia 
169 
169 
171 
172 
172 
172 
172 
173 
175 

17l( 



177 

IMI 
ISl 
1S4 
1H» 
192 



The Boaei of the Face. 
Tlie Maiilla, or Superior Maxillary Bone 

The Palate-bone '. . . . 

The Vomer 

The Inferior Turbinate Bone 

The Nasal Bone 

Tbe Lachrvmal Bone 

The Malar' Bone 

Tlie Mandible, or Inferior Maxillary Bone 

Tbe Hvoid Bone 

TbeSUllaiia Whole 

TheSutiiron ..... 

The Ewerior of the Skull 

The Interior of Ihe Crnriiiim .... 

General Mor|)holngv of llie Skull . . 

Various FonoB of tiie Skull .... 



193 

196 
197 
198 
19H 
198 
191t 
201) 

avi 

203 
203 
203 
209 
212 
213 



THE ARTICULATIONS. 



Bv G. WooMKv. 



General (.'onsiderutiuna 

Kinds of Joints 

Kinds of Movement 

The An ici I lot ions of (he Trunk and Head 

Tbe Articulationn of ihc \'ertebrBl Col- 
umn 

The ArlieulaliotiR and LiffamentH tie- 
tweeii (he .\llas, Axis, and Occipllal 
Bone . 

The ArliculRlionH of the Thorax . . . 

The Temporo-mandibular Artiniliilion 
The Articulations of the I'pper Kxiremity , 

The Stemo-olavieular .Articulation . . 

The Scapulo-i;la¥icillar Articulation , . 

The Shoulder-joint 

The KIbow-JuinI 



215 
21 ti 

217 
217 

217 



220 
223 

226 
22H 
22H 
221t 
2;l0 
23:! 



Tbe Radio-ulnar .Articulations and liga- 
ments 235 

Tbe Wrlst-joini or Radio-ciiriml .\rticu- 
lationn '2M 

The ('ar])iil .\rl ieul.it ions ...... 237 

The CnriKi-nielucariint nnd Inlcmieta- 
carjial .Anii-ulntions 

MetnairpopbHlanKeal and Inler|)halnii- 

Beal .Articulntions 

The ArliculatiouH of the Pelvis . ... 

The Articulations of the Pelvis nilli the 
Last I.umbur Vertebra 24(1 

Tbe Siicro-inrcygejil iind IntercoiTygeal 
A rt irulat i< HIS 240 

The Sacro-iliiu' .Toint . 24() 

The Symphysis Pubis . 242 



2:t8 

239 

240 



CONTENTS. 



11 



PAGE 

The AniculationB of the I^wer Limb . ■ ■ 242 i 

The Hipgoint 242 ; 

The Knee-joint . , 246 

The Tibio-fibutnr Union . iJO 1 

The Ankle-joint ^1 : 



PAUE 

The Tureal Joints 253 

TbeTarxn-nietatarBBland Intennelataisal 

Articulatioiia 255 

MetataiBo-phalangeal and Inlerphalao- 
geal Articulatioiu . 256 



THE MUSCLES. 

By F. H. Gerrish. 



265 

267 
•V7-* 



(ieneral Confiderelions 259 

The Nomenclature of Mu«;lei 262 

Thk Mitsc'leb of tuk Uppek Limb. 
Movements of the L'pDer Limb .... 
Miincles Muvinj; tlie Shoulder .... 

Must-les Moving llie Arm 

Muscles Moving the Whole Forearm 277 

Musclea Moving the Outer Part of tlie Fore- 

snn 280 

Musi-les Moving the Whole Hand ..... 283 

Muwiex Moving the Kin^re 286 

MuHcles Moving the Thumb 294 

The Muscles of the Ixiwer Limb. 

MuHcleH Moving the Tliigh 3al 

Muaoles Moving the Leg 315 

Miudes Moving the WLole Foot 322 



MuDcles Moving Die Digits of the Foot . . 330 

The Musclkm of the Tbukk. 

The Muscles of the Back :»» 

Muscles in the Third Laver of the Back 33» 

Muscles in the Fourth Laver of the Bock -^t 

Musclen in the Fifth Groiip of the Back :i4:l 

The Muscles of the Abdomen 345 

The Muscles of the Thonu ;548 



The Ml'«;i,es of the Neck. 

Muscles of the Front and Side of the Keck :151 

The Ml'soles of the Head. 

Superficial Muscles of the Head X>^ 

Muscles of Mastication 356 

Mueclee of Exprexsicm 358 



The Sdpebficial Fascia 



THE FASCIA. 

By F. H. Gerrish. 



The Deep Fa8ci.s. 
The Fa.'^ia' of the Head 

Tlie Teni|)<>nil Fascis ... 

Tlie Ma^wcle^ic Fascia .... 

Tile Buccinator FuHcia .... 
The I ervioal FiU-oiii 

The Oilier Cervical Fa-*iii . . 

Tlie Midillc t'ervical Fnsi'iu 

The Inner Ccrvicfll Fascia . . 
The Thoracic Fnsciii 

The I'cclDral Fascia 

The diivi-ciirac'o-axillurv Fascia 

Tlie lutercrMljil I'lL-i'iii' .... 
The l'':L-«;i;p of the .Sliuulder . , . 

Tlie Suliscnpiilar Fascia . . 

The Suprii>piiH)iw Fincia . . 

The lnfra.«i>iuoiis Fiuicia . . 

The I >oltniii Fascia . . 
The Fa-^^'ia of the Arm .... 



36-5 



;i<iti 

366 
366 
:W7 
:J67 

368 

368 

:i6il I 

36!) 

370 

370 i 

370 

371 

371 

371 

371 

3711 



The Fascia of the Porearm 

The PoMierior .\iinular Ligament 
The Fasciffi of the Hand 

Tlie Anterior Annular Ligament 

The Palmar Fascia 

The IXinal Fascia of the Hand . 

Fascia! Sheatha of Tendons in the 
The Fawipi- of the liiiek 

The Verlcliral Fiiscia 

Tile Lumliar Fa-nciii . - 

The Fa-H-'ife of the .Viilimiiual Cavity 

Tile Transvenwilis FiLscla . - 

The Iliac Fa.sciii 

Thf- Pelvic Fawia 

The niillirat^fr Fascia - . . 

The Kecto-vc^iral l''a«-ia . . . 
The Fiwcia;of the IVrineum . 
The Fa-^ciii' of llie Hip and Thigh . 

The Fa.iciH:' of the l«g 

The Fascia' "( the Forit . , . 

MVNiJVIAI. I!rR--.K . 



land 



371 
372 

372 
372 
372 
373 
373 
374 
374 
374 
375 
375 
376 
376 



376 
377 
37K 
370 
3.S0 
381 
382 



THE HLOOD-VAHCULAU SYSTEM. 
THK HKAltT. 

By F. H. Gkrrikm, 

J>escri|ilivc .\natorny of the Heart .... 3«"i The Physiologii-.il .Viialuinj of the Blood- 

vt-sM?l> ...... ..,-,-. 3lKi 

Tiltc pKHHiiiuilii ... 303 The Arli-rii'- 306 

The Siliialiiin and Kelaliuii.'i of the The (.'aiiiilaries 308 

Heart 304 The Veins 308 



12 



VONTENTS. 



THE ARTERIES. 
By a. I). Bevan. 



The i'uLMUNABY Artery . . 

The Sihtemiu Abtekiis . . , 

The Aurta 



PAIpE 

400 
401 
401 



The Arch of ihe Aorta 401! 

The Thomrit Aorta 403 

Tlie Abdiiiuinal Aiirta 404 

The Brachi(K-e|ihali(; Arlery 405 

The Common Carotid Anery 40S 

The Left Carotid Artery in Ihe Thomi . . . 406 

The C!nmmon Ciiroiid in the Xcck .... 407 

Tlie Kzlei-nal Carotiii Artery 40il 

Tlie Internal (.'aroliii Artery 417 



The Subclavian AHery 419 

I The A:iillarv Artei'j' 426 

' The Bmchial Artery 429 

The rinar Arterv 431 

The Eadial Artery *» 

' The BrancheB of the Thoracii' Aorta . ... 441 

The Branehen of the Abdominul Aurta . - . 442 

The ('omnion Iliae Aiteriufi . 447 

The Internal Iliac Arten- 448 

The External Iliac Arten- 4S2 

' The Fenroral Arterv . . '. VA 

' The Pupliteai Arterv 459 

'• The Posterior Tibial Arteri' 460 

; The Anterior Tibial Arterv 4611 



THE VEINS. 



By G. WooiaEY. 



The Pulmonary Veins . 
The Sy.^temic Veins . , 

The Veim of the Heart 

The Superior Vena Vava and ita Tribu 

tarieu 

The BiHebio-cephnlic ^'ein8 . . 
The Veins of the Head and Neck . 
The Venous Sinuses of the Cranium 
The Veinw of the Uptwr Eilreinitv . , 

The Superficial \'einB of the t.'pper Ei 

Ireniity 

The I>eep Veina of the Upper Kx 
Ireniity 



468, 

469 

470 
471 
471 

477' 
481 

482 < 

484! 



The Veins of the Thoracic Wall . . . 4ft4 

The Veins of th« Spine 486 

The Inferior Vena Cava and itH Triblitune!i . 4S8 

The Veins of the Abdomen 488 

The Common Iliac Veins 490 

The Portal System of Veins .... 491 

The Veins of the Pclvia 493 

The \'eins of the Lower Eitreniitv .... 49& 
The Sirperflcial Veins of the Ijmii' Hi- 

Iremity 49-'i 

The Deep Veins of the l.«H-er llx- 

imniily , 4iNi 



The Fuh'AL CiRcfLATioN . . 



497 



THE LYMPHATIC SYSTEM. 
By F. H. CiERRieH. 



The Lymph-vessbls 



4)ftl 



LVMPH-NUDBB AND OTHER LyMPHADENOID 

STRrCTfRES 502 

The Xodes of the Head and Xeek ... 5fr') 



The Nodes of the I'pper l.inib SOS 

The Nodes of the l-o»-er I.inib 509 

The Nodes of the Thorai 510 

The Nodes of the Abdomen 512 



THE CEREBRO-SPINAL AXIS. 



By F. II. (lERRlBII. 



(ienenil Coiwidenitiiiiis , , , 5|:l 

The Ciivily of the Cerebnvnjiinul Xxit . . . 515 

Till' Walls iif the Cerebnwpinii I .\ii« . . Sltt 

.\ UinKroniniHtii' IXwcriplion of the l!r;iiii 521 
The Pmseneephn Ion — The Kepion nf (lie 

.1.i.itpnil VentriHcs .124 

The Cerebrum .... ri-2i 

Thi-Surf:i.-e nf theiVri'bnun ..... o24 

The Callosiiin .'i;t2 

The Fiiniix -'At 

The .interior I 'ouiini-wure 'iS? 

Tile St-]iluni I.iiciihmi ..... .'>;i7 



The Caiidiite Nucleus 53^ 

The Leiitictilar Nucleus 540 

The Claustrimi .')40 

The Amygdaloid Niick-iis . , , , .'>41 

The Veliitn Inter] iiwil urn 54] 

The Thiilnnienecpbahin^Tliv ItcRion of llie 

Tbini Veiilrlcle .>46 

The Thaliimi 547 

Tlie Intcmiil (iiiwiilc 5-'i2 

The Mi-senci'pbilnii — The !{««!'>" "f ''"' 

Aqiieiliicl .5.53 



CONTENTS. 



13 



PAQE 

The EpeDcephalon — The R««on of tlie 

LpM* Part of tlie Fourth Ventricle 5S5 

The Pons 555 

The Cerebellum 557 

The Meiencephnlun— The KeRion of ilie 

Lower Psrt of ihe Fourth Ventricle 561 

Thetftlongata 562 



I'AG r. 

Internal Structure of the Oblongata . . 5t>4 

The Lemniscus , 567 

The Fourth \'etitricle 668 

The Spinal Coni (The Myelon) . . hm 

Tlie llembranes of the ll^rebro-spinal A ri« . 676 

The Menibianes of the Brain 576 

The Menibranes of the Spinal Cord . . 576 



THE NERVES. 



Bv W. Keilllr. 



Thr CEBEBBi>apiNAL Nkrvbs 



The Cranial Nerves 

The First or Olfectoir Ser\-e . - 

The Second or Opiic Nerve . . . 

The Tbinl or 'Vulo-motor Xerve 

The Fourth or Trochlear Xerve 

The Fifth or Trifacial Serve 

The Sixth or .Midiicent Nerve 

The Seventh or Facial Xerve 

The Eighth or .^iidiiorj' Xerve . 

The Xinth or (ilntwopharyngeal Xerve . 

The Tenth, VaKuo Xer>-e, or Pneurao- 
KflBtric . 

Tlie Klevenlh orSpinal .iccessoiy Xerve 

The Twelfth or UypugloHsal Xerve . . 
The Siiinal Xerves 

The Ventral Primary Divisions .... 

The I'i'irical Xen-es 

The Cervical Pleiiia 

The Brachial Plexus 

Branchy given off above the Clav- 
icle 

Branches given off below the Clav- 
icle 

The Mii-wulo-cutaneoua Xerve 

The Median Xerve 

The Sm;il! Intcitial Culaneoii' Xerve 
The Inlenial (.'utaneoua Xerve . , 
The I'Inar Xerve 



531 

563 
585 
586 
589 
592 
592 
604 
604 
608 
610 

611 

615 
615 

617! 
622 i 

622! 

622 

625 

625 

626 
627 
627 
631 
6.11 
631 



The Circumflex Kerve 632 

The Miisculo-spirat Kerve .... 633 

The Thoracic Xer\'e» 6.18 

The Lumbar Nerves 641 

The Lumbar Plexus 641 

The Iliohypogastric Nerve .... 642 

The Ilioinguinal Xerve 643 

The GeDitocniral Nerve .... 643 

The Eitemal Cutaneous Xerve . . 643 

The Anterior Crural Nerve. ... 643 

The Obturator Ner\e 645 

The Accessory Obturator Nerve . . 646 

The Sacral and CoccjBeol Xerves . . . 646 

The Sacral Plextis 647 

The Pudio Nene 650 

The Great Sciatic Xerve 650 

The Imemal Popliteal Xen-c . , , 651 

Posterior Tibial Xerve 651 

Eilemal Popliteal or Peroneal Nerve .... 6.J5 
Fourth and Fifth Sacral and the 

Coccygeal Nerves ....... 657 

The SYMPATHETIr Nebtes . . 0.'>8 

The Sympathetic in the Keck 661 

The Thoracic Portion of the Uangliated 

Cord 663 

The Lumbar Portion of the Ganglia ted 

Con! 6<;5 

The SflcRil Portion of (be (inncliiitcd Cord , 666 



THE ORGANS OF THE SPECIAL SENSES. 



THK RKIX 66'Ji 

By \V. Kkilleh. ! 

Nail," and Hairs .... 673 

The Sebaceous tilands 67U 

The Swenl-Glands 677 



THK TONGUK . 
Bv F. H. Gehri^ii. 

IMber On^ns of TeiMc 



. . 678 

. . 6S0 

TIIF, NOSE 681 

By \V. Keilt.kr. 

The Xiwal Cartilntres 6M2 

The Xiisal Fi>Hsie 682 

Laviiies Opening into the Nasal Fossic . 684 

THF, EAR 686 

By F. H. GEBRisn. 

The Internal EJir or Labyrinth 686 

Tlie Membranou.« Labvrinth 636 



The 0*«<>u« I.abvriiilli 690 

The Middle Ear or Tvm]ianiira UH2 

: The Eitenial Ear . ' 6',16 

I IHE EYE 698 

! By W, Keili.er. 

. The External or Fibrous Tunic 700 

I The Sclerotic 700 

Tlie Cornea - ■ 700 

The Middle or Viticnlar Tunic 701 

The 1 lioroid 702 

The (iliarv Zone 702 

Thelri- .' 703 

The Inner or Xerviins Tunic 704 

The Vitn'oiLs 707 

Tlic l*iis 707 

The .■\iiiieouN 707 

The MnsrU'sof the Kycbidl. 708 

The Siipcrliciiil Appendages of the Eye . 7U9 

The Eyelids 709 

The Conjunctiva 711 

The Lachiymal Apparatus 712 



14 



COXTEXTS. 



THE ORGANS OF DIGESTION. 



Bv F. H. Gerrihii. 



CienemI CnnBiHerotionx 713 

TlIK SIciUTH llli 

TheLtiH 717 

The Cheeks 717 

The Hard Palale 717 

The Soft Pulnie 71B 

The Teeth 720 

Sets of Teeth 721 

The aiinw 725 

The Tawfcac 72.i 

The Extriiwic Miu<cle) of llie Tmijpie . 727 

The ftiABYSx 72« 

TheToiuib. T30 

The fivLLET 731 

The Abdominal Caiity 732 

Regions of the Abibiiien 732 

ThK SiMJt.lCH 733 

Tiinios of the Stomach 735 

The Sm.ili. Intbtise .... 737 

Tiiniui of the Stnal! Iniestinc 737 

The Duodenum 740 

The Jejuno-ilenni 1¥A 

The Lakoe Istbhtise .... 744 

Tiinics of the laifn; InlCHtine 744 

The (>cuni 740 

The Appendix 747 

Tiie Colon 74K 

The XscencihiK (.'olon 74K 



FAQS 

The Trannrerse Colon 749 

The Descending Colon 749 

The Sigmoid Colon 749 

The HecliiiD 752 

The Anal Canal TM 

Glakbb Accewory to the Alimentary 

Tubs 764 

The WaliTBiT-Glnndt" 755 

The Parotid Gland 755 

The Snbniaxilliin' Gland 756 

The SuHingual Gland 75« 

The E^inci'eaK 757 

Tlie Liver Tnil 

Plivsiologl<al Analornv of the l.ivi-i> , . 759 

A typica! Liibe ..." 7.59 

Arrjiiigenicnl of the Vessoli' "60 

The Forai of the Liver 761 

The Surfaces ot the Liver 762 

Bo«ierB of the Liver 765 

The Eitremities of the Liver 765 

7B.'i 

7G6 

im 

7li7 

707 



Tiinicii of the Liver , 
Support* of the Liver 
\'ei«el« of Ihe Liver . 
The Bile<luetN . . 
The Gall4)b>dder . . 



Tub I'r.RiTiisErji 76fl 

liesentericn 770 

Omenta . 770 

IJganientB 771 

General View c.f the Peritoneum 771 

Relropcritoneiil Fiiwit 775 



THE ORGANS OF RESPIRATION. 



Bv F. IL (Jkbrish. 



Physioloiriral Anatomy . 



The Trachea 77'.t 

The Bronchi 780 

The BronchiH TRl 

Minute Anatomy of the Lnnm 7R2 

(irow Anatomy of the Liinp* 78-i 



777 The Pleiini' 788 



Tlin Ijityni 790 

The'Cartila(,f*or ihi- ljir>-iii . .... "ill 

Tlu" I^iganienfr* c)f rlu* I.arvnx .... 792 

The Muwies of the Lnryni 7fl4 

The Lining of llie Larynx 787 



THE URINARY SYSTEM. 

By F. H. Gerkisii. 

The KinsKYi- .... 799 ; The I'rethm 810 

The Excrelorv ApiKinitns of the Kidneva . 807 1 The Female I 'ret hra 810 

ThoUretera ." . . 807 ' The Slale Irethra 812 

The Bladder K08 ! 



THE DUCTLESS GLANDS. 

By F. H. Gerrimh. 

TheSiiWn H17 Thcl'nrathvnmi,- ..... S24 

The iTiyroid Bodv M30 The Carotitl (ilands 824 

TheTbvran* 82:; The Cocevjteal Gland 824 

The Suprarenal Cnii-nlw" 823 



VONTENTK 



15 



THK ORGANS OF GENERATION. 



By (i, 1>. Stbwaht. 



The Male Ukijans op (icNSRATioN. 



TheTeHticlefl 

Tlie Vhb Deferens 

The Seminal VoricleH 

The fjacutalory LhicW 

The .Scrotuni 

The Spennalic Cord 

The Penis 

The PrnfUte Gland 

The Bulbiy-urethral Glanib . . 
The Musclex nf the Male Perineum 

The Anal Group 

The Genilo-uri nary Groap . . 



827 
833 
«M 

83S 
838 
844 

846 
S4I> 
847 
847 



Tub FE.^[ALt: Gruans of Oenekation. 

TheOraries 848 

The Fallopian Tubes 853 

The Itenw 855 

The VnKina 802 

The Vulva 864 

The Hona Veneria 864 

The Labia Majora 864 

The Labia Minora 865 

The Interlabial Space 8^ 

£rectile Organs 867 

Glands 868 

The Muscles of Ihe Female Perineum . . . 868 

The Mammarj- (< lands 869 



RELATIONAL ANATOMY. 



Uy F. H. Gebbish. 

Plane Sections 87;? Normal Skiagraphs 

Surface Anatomy 8f*;t ' 



896 



PRACnOAL ANATOMY. 



By F. H. (iERBISJl. 



DiRECTIOSK FOR DlWELTlNU - WW 

DiVlSIOS OP THE t'AIlAVKIt. . , 911 

The Thomx and I'pper Limb iH2 

Thiiniclo I iivitv 1>1"2 

Frraitiif tbp .Vrni lU^ 

Front of thf Forearm 1112 

The Palm - 1112 

Rack of Tbiini:! and I'pper Limb 1113 

Back of the Arm 1113 

Hackof [be Formirni !I13 

Kiicb of the llami <I13 

Thff Abdomen and Lower Limb ilI3 

The Abdomen !>13 

Abdominal CaTily - . 914 

Abdomen Proper ',I14 ; 

The Pelvic Cavilv of the Male . . 914' 

The Pelvic CavitV of the Female . 914' 

Tlie Male Perintfum '. 914; 

The Female Perineum 915 1 

Front of the Thigh 915 i 



Liner Side of the Thifrh ..... ,915 
Front of the l^eg and Dorsum of the 

Fool 1115 

< tuler Side of ihc I^er !)lo 

Hack of (be Hip !)lfi 

Baek of itie Thigh H16 

Bai'k of llic I*g 9Ui 

The Sole 916 

Tbe Head and Neck 916 

<'niniid Kegion . ... 916 

InKJitc of the Craninm 917 

Hack of the -Veck 917 

Side of [be Neck 917 

The Face. . 918 

Tera|ioral and Zygomatic Foasv , , , . 918 

Mandibular Ke^non '.'18 

Deep Part- of the Neck 918 

Prevertebral Region . 918 

The Orbit 918 

The Back 919 



TEXT-BOOK OF ANATOMY. 



INTRODUCTORY. 



Bv F. H. OERRISH. 



Definition of Aiutom)-. niu] Divlsioua «t' rlic eubiecu — Nanxs uml DuBinitiiUonii nf Surfacs 
WrtR. — The Sj^trtUB of Orusus, anil tlieir Fiini'lions, — The (Mier uf Tuiitoi. — Meihodw 
uf Siudy. 

AKATOMY is the wiwicc of or^pini/jitioii. It trttit* of (ho clnictore of 
. i>rpnnix*xl Ik-ui)^. NoI iiII of llii- Ix-iiij^s in llir world ciiii i)n>)»-ily Ik- wiicl 
to hiive a r^tnwUin: W'v iimy AjM-ak *if tlu> Hinutiin' of a HnwiT, however 
simple, but wi- m^vcr ni*«orinHt the idoa of tilnioliii'*- with a nryRtnl. The (Inwrr 
liiis }K-tnlH, 1111(1 oulyx, ami stamen, nml other jtavtH, cm-h ilitforing in loi^k, lexiun-. 
jttrvHiilli, mill u.HCt fi-om all the roht. The cryetal is of ihe name inalt^rial aiKi 
nppi'iiniito'' tliriin^honl : it lit a miK^ which in (xjiuiUy deibtc, o()iiAlly .'■tmiig, 
i.'()iially colunil in one (lort a.* in another — it is homogeneous ; thai is to say, tl8 
pliy^ifitl i|n:)h(ies art' cvenlv di.-trilnit*-*!. The Bower is easily seen to have 
4)iir<ti>*. •'och of which ha.s itn own peculiar olliee ; the cr^'tttal ban no oiyan.i 
u-imlt^vcr. The one in oivanizetl — it nas a etnictupe ; the other is not organized 
— it hai4 no fltnietnre. Tlierefore wo may study the attatumy of a flower, but 
(here U no anatomy of a crvstal for us to wtiiuy. 

I^et tin here draw a iH-itinction lietwcen th<? wonls onfnmzHi and orgntw. 
The fin*t relates to auytliinj; which hsw orgauw — parts which are diffenntiali'd 
from each other; tlie fietond is appliwi to things which result from the vital 
activity of organized bciupi. Tlius, caseinc. which existfi in milk and is the 
isharacterifltic material in cliecsc, i« oi^tiic, for it is a result of the activity of 
a living crealun-; but it ix not oi^uizcd, having my i-truetiire, one portion 
being exactly like every other. Many thiiig!< — for exum])Ie, wutcr — are neither 
urgiiui/ed nor urgiinic ; llicy Hrc inorganie. 

jVII orgiiiii/i'd lieiiigK belong to one or the other of two great gn>u|»s — plants 
and iiiiininl^. Th'- dintiiietion may not be eiwcniial ; indeed, there arc ereataro! 
U]K>ii the dividiiig-liuf between tlHW> grou]is whwe nuture is not yet detenuiiHti 
— |M-rh»pT< they are pliint.-<, perhaps tliey are animaU. But, iiitlioiigh it may be 
iinjHivaible to give a d<-finiliou wliieh >IimI1 Iiirltule all of either gmup witlknit 
taking in some Iielongiiig to the dIIh r, tlii-«i- tirnis are not in llie l(a>I likely lo 
niiNlea^l na. The .■^ludy nf tin' structure of pliintu is ejilled nyitiihlr •niiitoiiiy, 
and is thii4 distinguislnd from •miuinl aiuitomij, wliieli ha.* t(» ilo wilh tin- oiyan- 
ization of the members of the other gi-oup of ereatureH. 

Phymoloifii is ofieii used, careletvily. Hvnonynionsly with anatomy, but th<?y 

are slwolutely distinct. Anatomy Ls the sirience of structure ; physiologj* Ls tlif 

hcfenec of function. Anatomy teaches us what organ;* a plant or animal hiw; 

physiology teaches us to what use tJiesc organs are put. Anatomy »how.-i wliaf 

1 IT 



18 



IXTBODUCTORY. 



an organ is: iihvsiology fihows what an oi^in doAs, Anatomy may bo, nn<! 
Ultiinlly is, etntlied upon (lie (load crcutiirc : pliyHiolugx' can be studied only U[ion 
the living — it reiiiiircTi ur^^iiizatkin in iK^iuii. 

Of all animal'', llic Immsin wan the first whow nnatfmiy wn.^ i^tudiod with 
giviit can-. Natunilly, nifti were niori- iutt-roslid tn know what ihty could about 
Ux-'ir own bixlii.'-! ihari uIhiii) those of other ercnliire-'i ; and whi'i) thev did ttivn^ 
tigutv the kI ructiin- uf Ihe niendiei-!* of lower onlei-s, il wjjs to lie exjHi,-led tliilt 
thfv would iimtitntv eoniiwrisons befwecn the organs of llie latler and thosw- in 
tli«niselv(« whieli spemed to e<irrt\-.(>on<!. Thus it earae about thsit ihey ealled 
tlie wrieiiee of the ntnietuiv itf all other nnimalM cnvipiuYitivf anfilomi/, to diwtin- 
Leuirih it fmni the wieiiee of their own organizations, which is hiitimn anaiomy. 
Flf they had begun their study of animal structure at iho other end of llie seale, 
taking first animals of the siniplest organiziition and working U|i gnidually 
through il series, each member i>f which was more ehdwralely constituted than 
its immediate predecessor, until they reached man, the term conninnitivc aiiatomy 
would not. be useii in the wnse in which it is generally eraiilnywl. But, although 
we reoogiiize the defects of their mellnnl, we niuj't oonfess that in the jianie circuni- 
Btanees wi> would douhtlesK hnve tlone preciwily sis they did. Now-a-tlays, how- 
ever, the student i^ omtiselkil to U-gin with Niniple and easily uniierhtood struc- 
tures, in order to jm-parc himself (iir llie ii-ntlii-r i'oniprc>|ii'ii>i.iti of the more 
complex, and finally of llie ^llo^t inlrienfe. The .-tudy ol' (lie auatoniy of the 
lower HiiimnU i:^ an admirable — indeinl, the lK-i<t — prejianilion Ibr Ihitt of hunuiu 
anntomy. One who \n familiar with the .stniiture of one iiiiimal in (he gn-at 
group in which man Ix-lougs, a.s the ent, for example, will lind Inunaii anaioniy 
immensely simjilified. lint i-omiwraiive anauimy, ab a separate hraueli, has no 
right to a pijU'C in the eourse oi ftudy in a medical wlnjol, and only m-easionally 
and ineidenlally will it lie referred to in this Ijook. 

ilunian anatomy is 8ubdividc>d, according to the m^tmi employed in its wtudy, 
into two great jmiIs : gvam or mnmym.'opic mialnmi/, in ivbieh no aids to vit^ion 
aro cmployi'd, and tnimitf or wwriMttifpic anntomy, m which the aesiatance of 
Opticnl instrument); Is used. 

According to tlic nicthixi pureuctl in its study gross anatoinv is sulMlivided 
into fi/iil'-imttk and irhthiml. Systematic anaioniy, callwl also 'lr«n-ipl!i:e tijiat- 
fnnij, rcgnnis the Ixjdy a* made lip of ^jXentf^ or sets of organs. For example, 
«n>»ideriiig liie liiiman Iwing from tins point of view, wc find that it lijw 
a iicrvoui^ i^Vftem (bruin, ^piiml eurd, iier\'es, ete.), a eireu!utor>- iiystenr (heart, 
blood -vessels, etc.), a digestive system (stomach, intei^tiues, etc.). an osseous 
avslem (lM>nes, etc.), « muscular s_>-j<l<-m (muM'les, I'le.), a n'wpinitory system 
(lungs, windpi]>e, i>tc.), an excri'tory .ivstem (kidneys, bhidder, etc.), a ri-pnKlne- 
tive system (ovaries, testicles, eU-.). K nowledgi^ of the viirinti.-* organ.-< ei>niprisi-d 
in each of these systems is ensential to the praelitiomr of medicine and snrgerj'. 
But if he knows each of these sj'stenis only in a separate and nnassoeiated way, 
be is far fnmi being cquipiied anatomically as he ought to be. He still needs 
to team how each ]»art of every system is related to each part of every other 
nystcm, and particularly what are the relations of each object to all of the other 
objects in it» ncighljorhood or region. In other words, he must know his 
unatomy not only from the sysleiiialic )>oint of view, but from the irlali'ojml. 
Other nnnic given to this method of study are regional aiiiilomif. iK-cause by it 
Ihe body is ilivided into n-gions for iuvcstigiition ; (rtpor/raphifal (from the 
Grtrk word meaning "|ilace"), a term iiwil by civil enginecn' to deifignatc 
« survey in which the jxisition of every part of the territory involved i« deter- 
mined n'ta(iv<-ly to cverv other jmrl ; .lunjiml, iMiatuse operations c;iunot Nlfely 
be (Kn-fomieil without knowleiige thus lu'ipiired ; rmilli-ttl, becaii.He it ii* necessary 
to aix^urate diagnnsi.s of di.-'eiise oi' internal org:iiis. 

Systematic anatomy in made jMissihle by ili/mertinH, by which is meant the 
careful and delicate cutting apart of the various structures, ,«!> that they can be 
observed and atudie<l. It is practised upon the dead btxly. Much of relational 




INTRODUCTORY, 



1» 



^ 
¥ 



anstomy also «in be acquired in tliiK way \ but a very modem mfthwl hsft 
rcvraltfl II miilliltidr «f fiicU in thi« i-oniut-liitn nliich wi-re nnvioiii'Iv iiiikDovrn, 
n»d arc iiiai]jalilr nP duNioii-iniiifiii liy disMfiioii mUuk-. I'lii:* ik-w fiifthixi i.* 
tlial i>r liUine. nftiiwui. The Miiioii'' avt- nmiti' in tlu- fiillowing iiumiicr : a Inicly 
h frcuu-n mi hard ih^t a nav, iu i^iiliiii^ tlimii^i ii, <iiO(>iin1i'i-s no more rrftintanoe 
in ht>ti(* than in miL-H;l«. Oulii with a itau- an- nuidit iit any direction wliich one 
cJiourten, Ihu tlio most vomtnon are the horizontal, the verti«il sidewia*? (alao 
calli><l "coronal" or "frontal"), and the veitiral fon'-aiid-aft (knuwn al-ai ba 
" sij^ttal "). The cut having W-cn made, thp l^aw-<tuKt is ven,' carefully dpared 
aw'ay from the purfaci>i, and the rrlation^ of tlic |uirt« witicli liiive been l»ruiif;ht 
to view aro •■tndicl. As un elcvatiim of tcm|>cniture above the frrezing-i>oini 
will impair IIh- fixity of the I'Mvimenx, iiml uk it ix munifc-^tiy ont of tlie qiieiition 
to maintain nticli a degree of eoUl iHTiiianently or to jittidy the )^]ieeime»K com- 
fortably during it" emiti nuance, it ii< usual to |>hottigni|>li them, or inmiervc llicui in 
a [>n-»orvative fluid in Hal vc^i-Im (i^vrred will) jiliiiu g1u»K, or lo a<lo|>t txtlli of 
the,-H- devi<'^» tor coulinuiiijr (he sliwiy. Sriidiiits aro not ex[H'i'kHl to <iii tlii^ 
work, which involves f;n-jil lalmr, nkill, und, for intcritrotalinn of the a|»j»ear- 
mvvrt of tite iu<eiion^, a hi^h <l(-gi'o<' of anntontiad kiiowlMj?- ; but thi^y can aviiil 
tbentwlvej* of the results of this m<'thod by ntudying the actual sectioin or ca^ta 
of ihcm in their nx^ical weh{K»ls, or, wlmt is sometimes l>etter because more intel- 
"■ ligitile, |ue1ures of sections made fi-om photographs and labelled in detail. 

^linute or micrijumpii- anafitmy deals «ith those feaiiin-s of structure which 
li arp too small to be recognized by the uniiidi'd eye. It «in Ik- studii'd only with 
I^^IIk- a*^i«t!^I>lV of a mierosei)|H', A bnirich of niieniseopio auutomy is li lutofw/if 
^B((he imme coming from the <inek wvnl for " texture '), which i* the wience 
^■of th« tiwiM». But the uniue liislolog}- ha'« been much u«'d syiionymouniy for 
^^ mi«'iX)«^pi<r anatomy, llu- wholi- p-tling it/> deNlgimtion fiimi a part, an in many 
other itiM^ in our langnagi-. Histology is siHuctiiiiis ciilled i/fneral aiuilmiiy, 
I I>tyun.'<t! th« tiiwtioi are uiiitributcd to all purl^— are general to lliv various 

A homely ilhistratloti will serve tn make the ditfen-iu^' l«-tween tht-w viirious 

^^subdivisions of anatomy clear. \V'e may ns*- ihe »voifl " aiuiiouiy " with «-fi,-r- 

^■ence in arti6eial strut-tures, as, for instance, the aniitomv of a steami'n^ine or 

1^^ of a watch or of a lioiise. Ijot us, then, reganl a house trom the ]»oint« of view 

I successiveiy of tlie s\-steniatic anatomist, the topographic anatomist, an<l the 

histolopist. The first of the trio considers the house as mude up of sets of 

orgiius, u weries of a|i:irtn]ents devoted to idimentarv purposes, a« the kitchen 

and dining-nmni ; another set used for sleeping — tfio bcd-ehamlHT* ; one for 

t^tudy — ^tbe library, and i^o on : a system of IuIk* c-onveying water to varioua 

pmns of Uk^ establishment ; another lot bearing illuminating gas lo every rooiB ; 

u thittl supplying sk^m or hot air for raising the t<-ui)u-nitnn- ; and xtill another 

} e«rr\'iug on Ii()»id waste mak-rinis; large, vi-rlieal pipes by which injurious 

prirtluctrt i>f i^nihu.-'lion are cou»hirk-<l awjiy ; a <(tiiuirily of wires adapted to the 

rtoivt-yance of eleciricity lor various jturim-ies within the hotiae, and a set of mJs 

designed to keep eleotriciry out of it, Tims he finds whatever oi^flos go to coni- 

a home, and describes e.'icii set by itself, so that a person who dwires to 

now about any system of apparatus — as, for example, that used for heating 

or tliat fi>r sewcragc^-can Icam about it by consulting the record of the invvitti- 

gator'ji l>ln'c^^■lltions. 

The tojK^gmphie anatomist appniaelK-s the (piei-tion of the siriiotuiv of the 
Ilouse in an entirely dilV>-r>-iit way. He examines the building by such means 
that, without actually euitlug it into sli<-i>>i, he is able Ut make drawings which 
show jusL wlml th*--'^^ plane st-iriions wouki display if they were made. He does 
tit't concern himself with any sc[i«nite system of rooms or rods or pipes or wires, 
but he studies the relations which obtain between all of the objects which he 
Met) in each of his iniaginar>' sections. For example, he observes that the 
parlor is related to the cellar lielow, to a bed-chamber above, to a library liehind, 



J detii 
^pose 

^■kno^ 

I ^^ 




20 



IXTROD VCTOR Y. 



to a corridor nt om* ^iil4>, and a roofed {linuai an [wn fa^*H^. He tmti.'H ilie cli^'tric 
wireji, th<> vajt- and ttteani- and wat«r- and wa8t«-piiM?» within tho u'alb of 
tilt- room, tile <?hininey which projects into it, and the relations which thc-w* 
liU^tain to the room itccll' and tu eacli other. He jiriH-eedw thus until everv 
reeion ut' the halite is iuvc.vlii^ilcd iiiitl niaiiiied iitit, 'Mv\ when he has done ail 
this one can gi-t from his mcords a eoiuplcte idea of the relations of cvcrj' piece 
of tlic structure to rvirv other. 

Fiiiiilly coiiivf* iJu- hiMtolugi^t, who, disftwunling sy^tvin* of orfnunM and hced- 
k-w of i\\v rvlatiotit^ bctwwn various parts, Umk.* only at llio i<Iruclural materials 
t'nt^'ring into the eonipositjon of the lionse; in other word*, \U tiiwiKw, He 
find- lliat the hiium> in made np of stones, bricks, ItoartU, Ix'nni:^, naiU, ^lalfx, und 
niiinv other ihiiip-, which present to tlie eye detinito forms by wliieh they are 
ref-ojfnizatile. It inny be that some one kind of these structural el<-ntents varies 
in sltu))e !ind in otiurr respects in different mrts, as, for instan<'e, the bricks, 
which are of one form, size, and smoothness m the outside wall, different in all 
of these resi)octs in the inner wall, and unlike either of the other kinds in the 
fire-phices; l>ut they iirc nil readily seen to iK'hmg in the same eategorj'. 

bueh of tlii'w ihrci* nietliods of considirinj; the liouse h;w its iises ; each 
alone is f>een to iw imidci|niilc to n)riv('v ii eoni]ir('lieiiJ'ive idea of the building. 
An an-liilect ein|il<iyi» nil nl' tlniu : lie is, iis re^inin huiji>i-s, » i>yKtenuili<- anatomist, 
It rt'liiliouul aiiulomiHl, and ii lil:*ti>][i^int. ; he knuw.-i whiit tiu- origins of a building 
«rt>, how (hey stand in simwc willi i-cU'reMcc lo eaiii other, ano of what texlumt 
Ihey ai-e constructed. For exai-tly the same reason every practitioner of nH-dieine 
mu.-t l)e a human anatomist in all three of these ways. He tlnils one diseasw 
iitfectiuKa given H%-stenj — as, for example, the alimentary — and therefore has to 
know the oi^fans of this system as a eontinuotts series ; he meets with another 
disease involving, not a set of physiolojiieally associated oi'gans, but a numlier 
of parts which arc relnt«i to eacli other ii> a ge<^nij)hieal way. o<?cupying a 
limiti'd region, and coni^eciuvnlly he uee<U tu Ih- ue^iuaintcd M*itli the organs 
or jMirts of organs belonging to half a dozen different systems. In either ease 
he may be unable to tippn-eisto the eouiiition of affairs if he is ignorant of the 
(iiiKueH entering into Ihr coin iMiKit ion of ihr structures which an- in\iidi_-d. 

The lioiiv nmv be I'oiisidered unalonjii-allv fnnn still other |Kiin(.s of view. 
If it is in a stale of heiilth, the ntndy of it.-> sinn-ture is inmiuit tinalomj/ ; if it 
is in a condition of disi-ase, /("//o^y/im/ or iiiriri«/ iniatmui/. When (be organ- 
ization is stiidicil with esi>eeial rt-fen-iiee lo function, we piii-sue rlie method of 
jili^aiotoffieal anatomy. The consideration of the [dan oi- model ii|)on which 
oi^ns are formed conslitnies mot-jihotfit/ieal aiiniom^ : and as the discussion of 
such matlcm- is attendetl necessarily with inortr or less of speculation, the 
nynonyms phihiophu- and friiiwreiidriiidl mialowi/ iivv often eniplo_\-i'<i. The 
object which the investigntor has in view determines the divbiion of the subject. 
Tlius, if he stu<lie» the l«)dy with the pnqiosc of represeiitiug it in u jnctorial 
or jiliistic w»y, it is nrtiiUir, antifomi/ ; if bis mdy intent is to acquire knowknlgv 
which will be e!i]ieeially w-rvieenhle iii the pnn'liee of the beiding art, it is ttpplicd 
or fiinicnl ti>ialoiiii/. I'ntdiriU aiicUoiuy is a niimc einploywl to iuditsle the study 
of the IhkIv by dissi-etion. 

It will tie undefstiHxl, however, that we confine ourselves to human anatomy 
eoleiy : tlmt we rcganl it only in its numial aspects ; that, unless olherwisi' s|Kxri- 
fied, the adult c^)nd!tion is assumed ; and that we consider anatomy chiefly witli 
a view to the interest which it must liavc fi>r the student who desin-s to lit him- 
iwlf for the work of the iucili<-id profession. This will in\olve llie study of 
systematic, relulituial, and mientscopic iiuatomy. and in the treatment of many 
topics all thn-e of theise nulhiiils will go along hiuni In hand. l'rei|Uent!y the 
physiohigtcal auatimiy will i)e pivseuli-d at the ojH-niug of a section, l>ecause it 
is so much easier to nnderstaml a machine if we enter upon its study witli 
:i distinct idea of the work which it is capable of perfiirniing, tlian if wv have 
■10 notion of its function. 



I 



XAMUS AND DELIMiTATlOyS OF SURFACE FARTS. 



21 



^ 



The rnllowing fcabtilatioii will avA iti rvculling tlic prioripal jwinu whidi have 
been madv: 



Aittiotuy 



V^MJiUa 



Awiinal 



i CDaupHnlive (all 

lower animnb) j q,^ ^ MMttwopio 



Py)<t«iuiitlc. or IHecri pti v& 



Iltinan (nun) 



(MinuM, or Micm«x>|)ic 
(HiKtoloio') 



Kt'Ulionnl, Topcvrapliio. 



NAUES AND DELIMITATIONS OF SHRTAOE PARTS. 



^P At tlie outt^ of anntomical axnAv it i.i iiii|M>rtai)t In hnvo tlip rl«tn-tit poKsibIc 

^^ winception of tW liftiits set hv iiaiiire or l>v wtiivcntion In rlir vurioiK {Mirtit 

whioli will 1« rpferttsi to cvjastanily in the following |>agi-ti, and iilwi ro Iwvi- fiir 

each of t\wse pitrtti a iKinie «Iiich sliall be used for tJiat iind for iioilitiig cUn'.. 

AU partH, evpa the minutest, liave leclmieal naraeif, which are Latin in form, and 

almoi^t all (»rt» which are visible without (IiH^ection, and those which are bronght 

to view by ac-eidciit, have, besides the seitiitific, vcrnacnUir appellations — reimea 

iven by t)un-nte<lii-:il iKf;>|)Ie who ne\'er had a thought of Knowing anatomy. 



^eu: 



1^ 



!ic iwieiitific naiiii- of a juvrt is understixxl in every Imid where medicine is 
'cuitisTiK-d ; the veniueiilar (le!^icn;itiuti itr iine Inneuage Ip cener.illy dilTcivnt 
fnjni thai in i-very other, and trtiimiitly cMsi-nliiilly w. Thn^, wh'al we call 
••Itead" in Kn^'Mh •'' "t*tfi" tu l-'rei'ieh, " kopf " in Oernian, "t.*ia" in 
Italian ; and the itnalomi^ wbn i^t aciiiininted with no modem iHiif^iii);!' hut his 
own Oiin underntawl only that one of iliese woixU whieh iwhtnjr* to lii^ luilive 
tongue. "Capiii," however, means the Mime thing to Knjrlish, Kivneh, (■■"rman, 
ami Iialian, for all seieniille men are Mipivihed to know someihing of l.itin, the 
language of scienlilie nomenelature. Onlv a )>miill projxirtion of the nanu-.4 
])|)lioable lo anatomical t>artM \h inehided in v\w vocul))ilar\' of the eomninn 
people, but areitfkmist* w'nerally use these in their writings ; lor llio suggestion 
of |>edantrj' which inevitably would come fi-om the invariable emplovment of 
t}ie teehniciil temis iiifitead of the exi^-ting vernacular words would be almoiit 
intolerably offensive. Unfortunately, liowever, quit*- a iiumi*er <»f the^e \'ernac- 
tilar titles are UHed by an.-itomi^tjj with different ^JgnilieatiuiiK from thu<>e which 

,ey have to the uiii^eientilii; ; and heuee it R-ema ueeessur}' to exphiin wliat 

itiuiing wv shnll ntluch to these words, which liuvt- been tiuuiliur lu lu from 

le crodle. 

U niay seem lo aome reudem iieoilleM lo undertake ihiH eimuienitioti HnJ ileSnilion, But 

[-a br^ ob^rTali»ti <jf molimi sdnietitalhruiiBh iiiiiiiy ,v*-aM lias (kmnriMrn'O'l ili«l it is hiRhly 

|d<Wn>Mn lo i)i> eiiu?t!y x\m lliinn. IVrijilr' nl' m<i<'!i imiri! lliiio i>riiir>iiry iiilcllijirtKn and cduca- 

Itiim nrcly liiivi- any iik-n ol" l.lii.' (litli'n-nci' U'livi-i'ti iIr- Diruiiiui; wlii^li iimny a woH liw to 

Plimlital men lui-.l tlj;il wliiidi i.i :lINu'Iil-i1 [>i it ui'iiLTully. ^^'bvo ii siin.'^>ii btani throB^i ^ non- 

DiMliral suuiVL' dim » ii'tx-iti \vm hrokcti u ]ty i>r mi urni, lie simply itathi^nt the ruii^n-wioii (hni. 

a tTMiture m stippcwtl lo linie occiirroil in a lower liitili in ihi^ otic ci<m> hii<I in nn n|)fHT hiiili in 

|h(! iittK-r riiH-: hiil if W i>r nrni Ik montii'iii'il by it incilii-jil mnti. be kmiwii tb»l tliv tliird 

w.-i:i)i<:iit iii' llii^ lum-r extn-inily in iiiL-iiiit in tlu- fir*t iiinlaiu'c. aiiJ tli« ta.i:i)[|'l (itiKiueiil ol' iho 

f>l<ur exireinity in ilie net'und. " Wrini." tu the lally me&iis an^'where from (h<; upper leyirl 
ihe mim i» nearly haltWa;,- np (hv I'orearni; "hip" is used instead of "ihiijli, ' niciitinn 
of till- lailcT. for Kontc! incxnlif.ilili' ri'ivjun. U'lnif nt prownt eonsidcn^l ovi-ri inorv* iiidi"IieBte 
Jma thai of "leg." f»r wbidi iw.lile xuasv Iiil* siilislilnlnl "limb. " Tbtw.- Ti-w Beleclions fhtni 
I ojiuidenilile nuinber will htvl'. it i« IioikhI, lujusiify ilie Hltviii)i( which is here inudc in ihc 
Aorcat of prccisiuu of luiiiiiitLX'O und of (IioukIu. 

In order to understand the a|ip1i<nti<>n of the ti-rm» intended to designate tl>i> 
Fetation in space which different pnrts of the boiiy »iir«tiiin to ratrh other, it is 
necessarv' to ktmw what i;" reganUii n» ihv aHittomiiy'l pmition. This is lh« erect 
'attitude, with the iKilmi^ of the hiimlx lunied to the front, and the solceof (iie 
) f eel hiiriKiintiil — -llml is, fiwing linwminrd. 
^H To thi! aii»t4>mi.tt " htaui " {<tipHl) immns all of the mass which is balanceil 



S3 



IXTRODUCTORY. 



on tlie neck, the front and lower jKirtionH being " face " (Jneifs), the iippr and 
back "cranhiHi," the tlivkli tig-lino between the two purts atarling at the so-called 
root of tile now iii the mitl-Iiiie, nnd extending on esicli i-idc beneath the over- 
hati}fin); brow:« and dowiiwiin) and iKiekwiinl to llic car. But " bead," in com- 
mon ijarljinee, niean>f at some time»i all ibat we bave ineliuKil, iw in dce-.ipitation ; 
at otber;^ only the eraninm, us in the n*e of the won! bejidiicbe, " Face" with 
the people cnibniees the uniitomie-at fiwM; nnd Jilwi the anterior }H>rti()n of the 
(Tuninni : « beiuiliriil fuw would be eoTinideivd d<weemt<-d if its pictiin' showed 
iicitliiiiji alxive the eyelmlU. And yet "taw'" in nftMi used in a more n'Mrietol 
fenne ibiin rhe anatomical, a." when one !<{>eaks of laeeache, meaning pain lu tlie 
cheek region only. 



OCUUIO- 

htfuviiri 




tio. I.—Stdc vlov lit pnnlum nnd Itiee. IP. B. 0.) 

The cranium is subdivided (Fig. I) into an anterior jtart, the "forehead" 
{frons) ; an upper, the " crown " (vair-r or gincipuf) ; a baek. the oecipuf ; and, on 
eueb side, the temple {(nnpiin). Then? are no fiurfaee-nnirkings by which these are 
«b»olulely delimited. At the lower portion of the teniponil region i* the flaring 
part of the wir, known by auaUmiiKt« tolx' tbo Iwifl ini|>orlunl division of the organ 
of hearing (iiom), Imt tbonfjht by iK-oph* eonimoaly to i>e nl>ont all of it, nnd eon- 
(♦Mjuentlv named " i:n-." Tin- lorebeiid liriniimtt'^t below at ibe " nose " (nrnnm) in 
the middle line, nnd on eaeh .-ideof tlii.-*, in an aii'bed border, n^iially ei'Venii witli 
short, erisp hairs, and ciilKii ihe "hmw" {tnijtcri'ilium). In the faee iuiniedlaltly 
beneath eaeh brow is an "eye" (oeu/iiJi), that is, an eyeliall or globe, shleldefl 
above by an " upper lid " {fiatiiebni mipci-iur) and below by a " lower lid " (jjul' 
pebra inferior), their edges fringed with dhort haii><, the " lashes" (cUia). Be- 
tween the eyeii and In the mi(hlle of the faee, lielow their level, is (he projecting 
part of the nose, which is all that in generally recognized as nose. This has 
pOn each side below an oix-ning, presenting down«ard, the "nostril" (jinrw), 
guarded on tiie outer i-idc by a flaring projection, the "wing of the nose" (flfo 
nan). What i;; eomnionly ealhtl the "bridge of the nose," a prominence caused 
bv tu« na»»l bono, lias no teehniml designation. At a short distanee Ifcui-uth 
t^ no«c i» « tninsvcix- slit, to whieh, m well iis to the cavity of which it is the 
opening, i» given the* name ''mouth" (r»<). Above tliia a|>erturv in tin: "upper 



NAMES AXD DF.LTXITATIOI^ OF SURFACE FARTS. 



23 



^ 




^ 



*hn" (fafnitm ntftrriun), iiiwl )in<!i-nii-ath it th<> " lowttr Wy" {Uifiium in/irian). Pop- 
aiurh', iIk- uim] month i» nfrcn ii)i|ilioil to tho Mw, an wltei) a wntiian i^ Miid to 
IiHVv a prciiy iiioiiili — ft coiiimoiit whioli mftiiUV-ntly is imt intomlpd for the slit- 
like opening, and still le*s for the cavity iwhiud it, (It mav not be amisH to 
call attention to the ia^^t (hat the Latin ns, meanio^ a mmitli, has oris for its 
ceuitive, aod gives origin to our Etigli.«h oral ; wli«rcas o», mcaiiiiiji » bone, 
1ft oMta in the genitive, and thus stands behind our English (»«eous.l The up|M.'r 
Up exten4lB verti«illy from thv no?* above to the fret- border btlow, and latt-r- 
aUy to the crcaiKT ^vIik^Ii conn^cs down iiihI otit t'rutn t\w hind bordi-r of the 
wing of tile nose, nnd ij- mllfil the ymo-tiilnitt tufruH ; the lower lip extends 
from it* frw udge aliovi- to « tmiisvorjic rr*-,»«', ihe rnvniit^nbitil snUnui, which 
prwwnt* » downwuril oonwivity, and sf^uinibM the lip from the chin. The 
middle jNirlion of llw iipjwr lip proji-cts liirthor downwanl lluin do the i^rts 
ivhirh iHiiind it latvntlly, and it.-< .-skin siirtinxr Is markoil by u ^oniewhul tri- 
ilcpnvstoit, till- i/hillruiii. The border of the nkiii of this lip ilt-Beril>c3 
_ ._. whieh 13 a mark of bi-aiitv, and is called by artisti* the how of Ouiiid. 
The "ehin" {mt^titum, ffenium) is the eentral prominenoe which finishes tlie feoo 
below, in and near the mid-line. It is not distinctlv separated from the checks. 
The main part of each lateral aspect of the face is the " cheek " {mala, gtrna), 
which pnvents a broad, quadrilatenil expanse, botmdcd below by the inferior 
border of the lower jaw, behind by the vertical portion of the Iwne of thi)? jaw, 
ab<»vr by tlw lower inarj^n of the orbil (tho wivity l<"lf;iii^ the eye) and by ti>c 
tiilgc of bone runnin^r txiek fn>m it, and in front aljove by llic wide of the nose, 
below this by tlie gcno-Inbinl stiliui^ and nn imaginary line in continuation of 
this. The outlines of the lower part of tlie face are determined lately by it« 
trsniework, the inferior jaw-bone {mamUbu/a), which, with itK various attach- 
ineuta and coverings, constitutes the under jaw {marilla inferior). The upper 
jaw'bone is the t^ta^ng tipon which the frroiter |uirt of the central zone or tho 
fcee rc|>c«ei-. On &e|Kinition of the lips the " teeth " {dcnie*) are seen projecting 
bcyoufl the " gums " (ffiiif/ii'<r) in two archcf with the convexities forward ; and 
on deprcw^iuft tlie lower jaw a view of tlw cavity of the mouth is obtained. In 
it* floor we soe the mn.'sciilar " tongue" (/I'lijfuu) with it^ rough up|H?r surfiwrc; 
ill* riMif id fonnwl by the "IianI palate "( /wi/n/mn rfiinun), and behind is tho 
"wifi inihile" (/wi/'/f'im tnollf) Imiiging like a phort curtain over the bttjso of the 
tongue. Between the two upright ridge.-* to which the Koft iiiihitj^- extcmU on 
each .^de is the "lon.-<il" {ttimtUlu, unii/r/il'iln), an<l ln-nealh the peiidiilonm veil 
of the palate we can s«m' a [lart of ilie rear wall of a cavity for whii-h tJie Uiity 
have no name, but which we know a.* the jihiininx. 

The " neck " (cfrrix, eolium) eonnoets the head and the trunk (Fig. 2). In 

!ftont it cttends from the level of the lower jaw to the " breast-bone " (atermivi) 

in tlM! middle line and the "collar-bone" {clm-ieulfi) on each side. TheF« bones 

can readily be felt through the overlying structures. Ilehind, in the middle line, 

the m-ek e.\ten<ls from the base of the cranium to the seventh s«-gmcnt of the 

I back-bone or spine, the tip of which can l»e both felt and seen projecting beyond 

tin- plain- of any of its fellows aljove. Between thi^ iK-giuenl {mifhrn piominnuf) 

and tile iMliar-bonc* — that is, at the side;- — there is no clear (leoiarcatiun of the 

Lneek from llic trunk when llic up|icr limbs hang pai^ively : tlicrr is usually an 

Junhnikcn slo]*!' from the head 1" Ihe peak <)f the Khoiihlcr. Hut if the shoulders 

fare niirM}«l slnti^ht upward, a cn-iisi' if priHluci'd whi<-h slijiqilv imUcates the 

bonndaries of ihe neck for tun-thinlH nr more of the dUtam-c, and suggi-sts the 

line for the n^mainder. In (his uttitudc of hunchttl shouldei:^ the nci-k ruw» 

se a column from a depn's^uHl Iwse. Although not exact in every respect, this 

pehuictil delimitation of the neck is va-'tly more definite, as well as more 

stricte*l, tluin tliat which is in popular vogue eon<'erning women arrayed in 

is known as " full ilress," whose necks, varying at different times according 

the dielntcs of fashion, may find their lower limits anywhere between ihc 

>llar-lxine# aru] the iiijiplcs in front, and between tlic vcrtebni promineiu and 




5 



24 



INTRODUCTORY. 




nwnTH Dwi HI 'DuTi 

TriJflQ OtOiT 41 TH»IID 
k[CDi4o«'r D> kit QUO rot' 

FlRAT 0>Li1 on OJtl'T TOfl 



B*nW« Tl"T(Ut 

■o.S]1uinHM(, Hiiiu, PQL.Llr1l>H 



TiQ. 2.— Front vlow of & man In the anaioniJral iifialtion- On one lalpral bairih« jmrt.^ mrv labolled \T\ Y.T\g- 
lish, on tbc olhcr in Latin. Tho rltfht iipT^r limb Is drawn airajr frum thu trunk in urder lu bhow the arm mur« 
Ailly than 1a poulble when it Imn^e p^rpuudJcnlaTl}'- (K. H. M.) 



JfAMJiS AXi> DELIMITATIOXH OF SURFACE PARTS. 



' Finall of the back boliind. The word " throat " lias no armtnmiinil eijuivAlent. 
It is viiriiHii'lv liswl t() ilc^igtiate tho front part of tbe neck, or the lon-iili) and 
kdjaivnt parlf uf the Mift palate, or tlie pharynx, or tlio oipin of voice {laryar). 
HirIi tip on the neck in front is a hard protrusion, more prominent in men than in 
womvn, raitsrd bv the thyroid eartilaife of |)k- tur^'iix, and valktl " Adam's apple" 
(pomum Ad'tini) in playful oelebnilion uf (he mot<t noted and unfortunate gatitro- 
Domic pcriorinunw on n-cord. The m<**ltuii portion of Uie uefk behind is the 
"naiK- {nuc/ia). Just idmve the lop of thi- bn-iL-«t-bone i^ often seen a little 
pit, ejiteemed n mark of lieanly by nni!il>, wI>o have nami^^ it " DianuV pool." 

The ho<)y progtcr, a.« di^lingtiUhi-tl from the entire or^minni, i» known iu< the 
" trunk " {fruueua), and pn-.tenl.i two grand divi»ion», the upper of which Ls the 
"chest" ((Aorai;), the lower the "belly" 
(aAf/ooMit). The superficial line of separa- 
tion between them h pronount-c-d, and is 
mtide by the bones and eartilagen which 
ibrm the lower border of the thoracit; ca^e, 
as the i>kek-ttMt of tile upper cavity is called. 
Slopinf; downward and outward from the 
lower (Kirt of the brea<it-bone, the boundar)'- 
line i)f PontintKil Uickward at the sid(^«, and 
then oblitpiely upwani behind. But tbi^ 
(iHriiMV nmrkiii^ i^ by no ine«iis an indini- 
tiun of iIm- n-lntive !«ii:e of tin- two uivili(':< : 
it only Kbowf the line aton^ whii-h i? at- 
tmdK^ t)»e iia.-«> of n inu.'iouUkr dome, the 
tliiiji/imffui or niidrifl', whose central portion 
ri**-* to the level of a point about halfway 
up tlie sternum, and .'^liiitH off the cavity 
of till* tliorex fffiin that of t\vr abdomen. 
TIiiw, the summit of the bei!y-«ivity is 
roundc-d, present in^ a marked eonvexity 
□pwnnl, and the base of the chest-cavity, 
into which the former rLws, i» correspond- 
ii^Iy concaved. 

l*'rom the front of the chcHt of the adult 
female there projects a nearly hemispherical 
maaa on each aide (Fig, 3). This is the 
" bresflt " (vMnttnu), the orfpin in wliicli 
milk i« formiil. The vall<-y between tbii-P 
hilloekf is ])niiKTly the " bwotii," bnl thta 
wonl 18 oAcn tir^vil iik !>ynoti vinous with 
bren.*t. A\ about the ci'iilml jx'int of 

each niamma staiidn out the nippU- ()r leal {nuimmifta, literally " the little breast"), 
it:* liatie Kurrounded bv n i-irciilar !<]taee which is distinstusbcd by the darkncfia 
of its fikiu, and It ojilled the «iwj/(i (literally "the little area") or tbc"halo." 
The male hiw no milk-foniiinj; ori;an, but he has in tbe lamc relative »ittiation 
upon the chest-wall slightly dcvetojR'd mummillfe, which indicate the position of 
nidioii-ntfiry mammic. TIkisc ;ir^- jrixMi illii-tnitions of a rule that (he ;;^nenitive 
ori^.in-< whii-li are fully dcveliipiMl in one «-x art- alwrtcd in the otlier, being rep- 
ra-*enled in the latter by some Hitle bulj^c or dim]>1e, whose only use seems to do 
to suggest tin: narrow ewape of it* po^-'e.sMwr from tx'ing of the opposite sex. 

Tlie belly at its upper central jKirt prf-«enls a shallow ileprcssion, popuhirly 
culled the " pit of the stomach," but leehnirally Krrnftietilm amlut, which litcnilly 
meant* "the little pit of the heart." Tlii.- (•onfu'<ioii of tinmcN nri^n's from the 
physical (not the tij;iir:itive) nearncHs of the begirt and «Ioniaeli, llic inic resting 
Upon, the other lying underneath, the diaphnigin, ami both being in the region 
of thin flight hollow. Farther down tu the mid-line, and usually nearly oo 



•iib, 




FiD-K— PtMit orw«a«r»omMn. (F.H.a.> 




26 



INTROD UCTOR Y. 



a borizoDtal drawu between the highest poiats of the hauDch-bones, is an irreg- 
ular, puckered dimple, the " navel," called in Latin umbilicus, from umbo, the 
button in the centre of an ancient shield ; so that we see that the childish name 
for the part — belly-button — has the sanctiou of a noble classical derivation. 
Following down in the middle line, we find at its lowest part an area which 
extends considerably sidewise, and is covered in the adidt witn crisp, curly hairs. 
This is the pubm. Behind the skin of the pubes the male has a little pad of &t, 
and the slight elevation which is thus produced is sometimes called vums puba — 
that is, tibe mountain of the pubes. In the grown female there is so marked an 
accumulation of fat here as to make a very noticeable hillock, which is named 
mone Venerw (the mount of Venus), in honor of the Roman goddess of love. 




FiQ. 1.— The nule perineum and sairoandlog p«rta. (Alter Hli.) 

Bunning obliquely upward and outward from the pubic region on each side is 
a crease which separates the trunk from the lower limb in front, and is called 
the "groin" (inguen). The name is usually applied to a narrow but indetermi- 




Fio. 5.— The fumalu peHavum and aurroiindlDji iiartH. (After HIb.) 

nate area of the abdomi'n immediately above this wliallow furrow, and tlio adjacent 
area of the thigh jut-t below it. 

Below the pubes arc ^omt- of the generative organs — those whirh are super- 
ficially located, the external genitals {genitalia cxtenui). In tiie male is tiie organ 
of copulation, whose technical title, penix, has practically disjilaccd the entire 



NAMES AND DELIMITA TIONS OF SVBFA CE ^ARTS. 27 




,liALLEOLuaEJTTFRHUa 



Tin. G.— Back view of ■ tamu. On one lateral half the iiampB nf the parts are given la EDgliih, on (he other 

In Latin. IF. H. G.) 



2S 



mTRODVCrtiRY. 



group i»f Anjrio-Saxou tiam» by which il viw- formerly known. The frw* i-nd 
of the penis, the " head," *>r •jUni* itii\in (literally " the f;liinil of the peTiis," from 
ilji rwemblaiiee \u some inkTiinlly loeiited siTri'tiiij; gliindi"), in eovend liy ii lotifr, 
movable folii of intejrtiiiifiit, ihe "foreskin," or " ure|iiiie " {fnr/Kithim]. A I 
tile ti]i of llie glnns is ii Ittlle slit, meeiUiM iti-iiiarhii; tlie termination of the eom- 
iiion [Hi.v«age-»iiy *if (he urine antl wmcn. Ilehimi the penl* hiinjis the " Iwij:" 
{iirr'ilttm) ill wliieh an- !iU."[H'n<leiI the ettsential male oi^aiu- of ireneration. the 
lwo"l)alU" or"stoneH," whieh are more iir^imlly «illej by iheir Latin name 
/(■s(™ (witnesses) or by the Anglieized dimiiintivo of this wortl. " testieles." In 
tJie fenijilo the gn>u|) of external jreiiilJils 1* (IwijrmitMl by the name viilra, for 
whieh modern Kn^li^li diclionariew. with ii fiir^tidion^iie^e not silwiiys imituted in 
p(i|)ular sjK.'eeh, allbrd no 6iiiplf-\vonI synonym. Thcw iflrnetuns are wjmetiniw 
calli'd i/u<lrii(hi. which meiin« " ihin^ lo be iiHlmnxil of" — a» if siieh a eritieism 
could jnstly Ix- iipplied to the organs which are miessary fi»r llie {H'r|H'inaiioi) of 
the human nice. The vntvii [iivsents a fore-and-iift elefi, whieh sliirt.- jtisl bilow 
the |kiIk-k and runs baekwani heiween the thighs. This fissui-e is hounded laler- 
iilly by thick folds of skin, ttititi utajora (the greater lips), njion sepanition of 
wiiivh rnv seen the ciitorin (whieh is the suppressed representative of the |»enifl), 
two thin fcihLs of nienihrane, /o&m minora (tile smaller lips), the mfatun iirinarius, 
iinil the ojx'ning of the viu/ma, the tube which lends to the "womb" iiilmig). 
Keliind the external g<'nitaU of both sexes, between the thighs, and in front of 
the lower oiwniiig of the bowels is a narrow an tcRi-jw* tenor ari-.t ealled prrinnim, 
a woitl with no vernaenlar e(|iiivalenl iKitf. 4 anil ;">). Tlie rear limit of the 
[K-rinetini is marked by the outer opening of the nuui*, the teriiiinid portion of 
the alimentary amal. 

The iwsterior snrfiKv of tlio tnink (Fie. 6), ppnornlly ojiIIimI the "Iwck" 
(ihrmnii), showfi in the middle line from end to enil a furrow in which appears 
aeontinnous ser-es of b<iny prominences, eaeh of whieh belonij^ lo a wparaie 
»e)riiienl of the pile of Is^nes called the si>inal column, or, naming the whole from 
M [tart, men-ly ihr spine or Imek-lKine. Between the lower margin of tin- thtiraeio 
euge an<l ihi; crest of the hip on eaeh side, in the rej^ioii known a& the ^mall of 
the haek, is a "loin" {luinbun). 

I'rojectiog from the trunk are the "Urobs" or "extremities" (membra or 
exirnnitfilfs,) arrang<-d in two |«iirs, an upper and a lower. Each pair has a 
liikiteml symmetrv, and therefore the slutemenis which apply to oDe limb ti*ed 
uot lie rejuated for its mate of the opposite side. 

The " iipjier limb," " upper extremity," or " tliomeic exti-emity " {mnnf/nim 
mperiwf, exlrftnitae nuaerior, or cxticmUiin fhoranca) is divided naturally into four 
distinct segments. Theae, in regular nnier from above downward, are shoulder, 
arm, forearm, and hand. The " shoulder " (»m<w) connects the trunk and arm. The 
"arm " (braehiuin) extends lietween the sliouhler- and elbow-joints. Beneath the 
ithoulder-joint, and l>etween the side of the ehest and the arm, ig a pyramidal i^jiaye, 
with its t»ise presenting down wai-d, called the "arm-pit" ((ij-(V/«l. The "forearm" 
is known u tinlrhraehium, which is the exact Latin equivalent ot the English namie, 
and also n» cuhilw^, from which comes the name of a measure of length anciently 
employed. It inoludej* alt Ixtweeu the elbow- and wrist-joints. Its upper end u 
niark4>il behind by a prominenei'. the "cllww" {rmcaii). The fourth and final seg- 
ment of the upper llndi la tiie " hand " {miiimi). 'VUU in gubdiviik-d into u prox- 
imal portion, the " wrist" {fitrjitm), a oentRil jKirt, whiih eoni^litiiteK the body w/ 
the hand, the melitetirpii* (nuuining " lK'you<l the carpus"), and a distal part, llic 
" digits " {dif/ili). The front !»iirf«ee of the meljiciirpus i* the " jmlm " {palmii), 
and the bind surface is the " ba<'k " (ilnrMum mmniK). Tliere are live digits to each 
liand, nnrocrically named, b^inning with that furthest from the median line of the 
boily and counting inward. They have also other designations, which are used 
with euual or gre-.iler frequency. The first digit (dlffilus prhmig) is (he " thumb" 
(poflr-x) ; the second (digitus nc^andux) is the " fore linger" (dirfilii* index); the third 
ijHtjUfu icrttHs) is the " middle finger " idlgitm mcdiue) ; the fourth (diffitua ^wtut) 



W THE srsTEJJs or orgaxs and their FVXCTIOXS. 29 

ia th« " rin^ 6n^r" {dtgitfta anntUari*, fVom onhu^ "a ring"); and fb« fifth 
(diffittu ^uinttu) 'ta tJie" liUle finger" ((%/6m mtntmiia, lilerally" tJie least finger"). 
Each digit luis tJireo Kc-pncntfi, cKoept tlip thumb, which haa but two. 

Tfaf " lower limb," " lower exiremitv," or " pelvic extremity" (membmm infe~ 
rw*, r^i-rmif't* in/rrior, or r^riremitax ji^lrina) is the homolojrtM? of the upper — tnat 
it, it U hiiill on -siiht^tiititiully the same stnicluml plan.' It han four <M?;^iueuts : hip, 
thi^li, h^g, and fiK<t, which corrnspond rEspeclivcly to shoulder, ami, forearm, and 
hand. Hi^lwwu hipand thtgh ik the hip-joint : between thigh and leg, the knee-joint ; 
and hetwe<;n h^ awl P>ot, the ankk-joiut. Tho "liip," or haunch (">xn), is so firmly 
iinittil to Ihi' bark-hone that it sorve^i ilh a portion nt' the wall of (he iibdoiueii, 
the g«iil«-r cavity of the trunk. Behind the hip and immediately l»eiow the loin 
i.i a hirgi- nia.-w of mu.-<cle and fiit, (he "bnttoek" (nflfi*). The "ihijfli" extends 
from (Ju- hip (o the k-^, and is tcehnlealiy called yrwiw, whieh name i.- sl»o applied 
In the single bnn*^ that formi< it« framework. The prominence in front at it:« 
tower end is the " knee'' (^nu), and the spare oppuvite the knee on the poKteriur 
aspect U the " ham " (jmplre). The tiii»t»ke of mlling the hnttnckff the ham!> 
K often made, bnt haf no jiir^tiliration. From knee-joint 10 ankle-joint if the 
"leg" [•■riiK). hs niir biilgi.' is the "ealf" (mr<i or yiiMrorHmuiiy literally "the 
hf'lly of the leg"), anil (he Jiharp vertical ridgt- in friml h tin- "t-hin." .A( the 
lower end of the leg are two lutny pnniiinenee;', the "inner ankle'' (tnnllfituK 
iuternui') and thi' " outer ankle " (iniuleoltM externum]. Malfeohn ineann " a little 
hammer." The '* ftMi" (;jiw), like its homologue the hand, in divided into three 
jKirtA — a hindmost, the tai-ttun, a middle, the metaianw, and a foreniot^t or distal, 
the "digits" {dU/ili). The "instep" of jrapular nomenclature lias no equivalent 
in anatomical lerniinolog^', an it includes [rarts of both tan^ni^ and metatar^Ufi; 
ami. on the other hand, (here are no verniictiliir words corresponding to tardus 
and metatarsus. The pfirt of the tarv^uc which projects to (he niir is the heel 
iftUx) ; the lop of the foot in its " back " (flortmm prdiii) ; and the entire under 
mjrfiice Ls the "sole" ( ptaiUa), The five digits are designated numerically, like 
their liomologues in the hand, the count beginning, however, not at the outer 
end of the series, but at the inner — that nearer the nuxlinn line of the biwlv. 
Thu*, the " toes " or digits of the foot {il'i/Hi prilii) arn first, second, third, fourlh, 
anil fiOh {itrmm>. whWim, tr/fiw, </"«/-/i*x, anil t/utnliiM), rcspeclivdy. But the 
lirst lunl last Imve other names ulwo, the one being conimonlv culled the "grt'at 
10* " ( Wfrj ]mii», " the thumb of the foot," or kiiHux) ; and ("he other the "little 
toe" (tiigitu» mlnSmim ftnfiK, litcrallv " the t>nuille-'<t digit of the toot"). In giving 
the l^iiu namcH for the toes it w rarely neei.\'*>«iry to employ iW/x ("of the 
ft»ot") to dLHtingui.-<h thote of the lower extremity, tui the context indicates which 
limb is concerned; and it in never essential to say wiani(*("of tlie liand "), as 
this is understood unless the contrary is obvious. 

THE SYSTEMS OF ORGANS AlfD THEIR FTJNGTIOMS. fl 

In studying anatomy the thoutrhtful learner b almost certain to eonehide that 
be weds to know a great deal about ev<'rv otlier |Kirt in order to coniprt'liend 
fully the one which he lias in hand. No organ, however simple, is independent : 
«ven' one is so related to others, {terlia|)s to mauy others, that they are aosoiutely 
VMWnlial to its life. In the sume way it is true that some knowledge of (nanr 
is neees-^rj- to the eoinpielc, or even sufficicut, understanding of a single one. 
This fiurt i-onHtitntc^ a cliicf ob.iliieh' in the path of the sinat'imictil student ; hut 
it may Ih' ilimini«h«l very consiilenihly, iiiid its residue rendered le«s discour- 
aging, by his having prcwnteii t<i his mind at the beginning of his wursc a con- 

' Tbr diftrroici- tvlwrcD bomnkigv and ntutlnRV mii>( be biuno in Rilnd. Jtaatology r«1aU« (■> 
niiniLarily at iirutlnre, muJo^i/ in HIm^iiiv^v of fiiiutioii. Tlii^ Iwo do 1101 altrMys ten (umllior. Vor 
tfjnotpW, tkp ti[-|H'r limb of » iiiun iinil thni «f u Inot hfv huniolugoiu. Iicoiuw iliry arv i-oiutmc(«) 
on Umbuu* plno; but lliey arv nol Hunlogow. iKrausv tin- one iiuard Tor iitdiciwlon ijcntt.p'inst\ imd 
th* Mber for iMnnrnttan { HjinK). Tlut oripuiiinltnn in iho iw(> iau-* U htrikliiu'y "imiiar ; Oiv lane- 
(ion Kndl<«]lj41il«rviil. But cOTOparv tli<- wlnjc of 11 U11I Willi lii:it a(n btiUcrlly ; both arv ilvr<-lcil 
to tilt) oinic ate— uiLincly. ()yin^: but lliry :ii« mcoliiillir dtlTrrrnt in Blructunl plan, at am be iccn 
-on (he iDoat cursor; inii|«ct)on. Tliercdirc tlicT uv ■ludoipHM, but not bitninlcigoiu. 



30 ^^^^^r INTBODUCTOR Y. ^^^^^ 

cltui! recital uC th*" priiKrijml otmuis of tlie body and a Ktalenieut <t( ilie cliii-f 
fVmctioii of eaoh. In thin way lie will learn a number of most uiiefiil a]iatonii<;al 
filets, and they will l»e grasped all the more readily bet-nuse they are strung on 
a [ihy biological tliread. In the tew succeeding [>agcs an effort Lt made to affonl 
the titudeut jimt this aasiiitaiice. 

Orf^ans Removing Waste Matters. ^| 

The human body is a machine, and, like every other machine, wears out in 
using. \\'<' all know that even in circumstances favorable for the prewrvation 
of a corpse, siit^li as coolness and drynesK of the atmosphere, it iiiidergoes destruc- 
tive changes so rapiilly thai before many days have iMiwied what was once an 
ob)ect of iKflUty and the occjwon of dclighttil adniimtion becomcj- altugi'tlicr 
grewsomc and i\-voIting. Ami yet, >^wirt as Ih this piitrcfaetioti, the wearing otlt 
of the tiwiic.'s ill life i* nion- KjK-itdy. The greater the pliysii-al uctivity of u man, 
tJic more rapidly arft lii.4 t4-xtnro:f broken down. Every movement, howovcr 
trifling, every glance of the eye, everv thrill of sensation, every ihonght or 
emotion, iw attended witli dejitruetion ol^ snt>stance. The prodiKts of ilii.-; wacte 
are poisonous, and if retained in the system in any eonniderahle amount cause 
sickness and even death. Hut there are ehanneU by which these effete and toxic 
materials are continually escaping — namelv, the luiiff*. the akin, the kUlnrt/n, and 
tile bowels. Water, the common vehicle lu the brxly-cluingcB, carries them out 
in solntioo. The solvent and vehicular services of water are vcrj- mnnifect in 
tlic case of the urine, which i* loaded with the waste escaping through the 
isidneys; and they arc often a* plain in the i^iisc of the ]>crspiniiioti, which 
contains the efFete matters di.'>ehai^ed through the ^kin. The cserenunt which 
comes from th<- l>ow«l.-< is not in solution when it iippcar^. bnt this is due to it» 
loss of water subsecpiently to iu formation and during its detention in ilie intes- 
tine. Other products of decomposition aiv iHtrne out with every ex]iired breath, 
thiH being saturated with water, ils appeari* by its visible oundennation whenever 
the surrounding air is sufKciently cooled. 

The Vascular System. 

At this point there naturally arises the (jueslion of tVie means by which the 
varioHs effete materials that are constantly being formed in fvir\- part of the body 
get to the four outlets named. Thin carriage is a<?eoniplishe<! by the vascular 
system, which consists, first, of a coniplieatcd series of tiibe.s, the blood-fejveh, 
connected with which is a jxiwcrful organ, the hrnrt, which drives the biooti in 
a continuous current thnnigh them : ami, sts^^md. of another set of tubes, the 
Ipnph-ifvuU, whose stri-am of lymph How* into that of the bkujd. Almost 
evcrj'whcn- in the boily there are minute crevices between the elementary 
particles nivl thread" of the liwiie.i, and info thew e)iink'< the textlin-s dischurge 
their wji^ited molecules, always in sidution in water. These ti^nfH'ninnies com- 
municate with lilili- i-ylindriejil lubi-s, into wliieli tlie lii|iietie<l wa-<te is [xMirt-d. 
The lubes aiv lymph-vessels, and they eouduet tlu-ir contents to i^rtain bliMxl- 
vessel.s, where it niingh^ with the current of bIoH*d. Some etli-te nmtters jmiss 
from the tissues directly into the blood. The blood is contained iu and com- 
pletely tills the heart and the blood-vessels associate*! wnth it, these being, first, 
the arteries, which are tubes through which the bloinl flows from the heart (o the 
tissues ; second, (capillaries, microscopic tubes of wontfcrfnl thinness and delicacy, 
through which the blood flows in fhc nn'ilit i]f the tissues ; and, third, veins, 
through which the blixnl flows tiirny from the tissues. The heart, which i;* 
a kind of fon-e-puntp. drives the bliMHl through this great system of Inbcs in 
a ecBW'less xtreum, and thn!< brings it in |iructieat eimtnct with the tissue -elements 
tliat make up the varioiw (trgnn.-*, When tlie bh>od, Ia<len with impure matters 
firom ever}' part of the body, coinea to one of llie organs (kidneys, lungs, bowels, 



OJtGAXS SUPPLTIXQ yOURISHHEyT. 



31 



or jikiu) which is capable nf witlKlrnwing dcootupcmitioit-nrodnctit from it, llie 
particular poison whicli tins organ win nbi^trad is removea, ami tlie blcMnJ is by 
just ho mnch rendered kiw impiirf.-. Coming to aJiothcr one of thpm, it gi'ts rid 
of tliL' foul material whirl) i^in lie iuiluu>li.-<l lit thix door of exit : und i^o on at 
llie others. TIk" hing» «ri' m'W<t» tlir i-crlain cxorcitionlitioni; (^iilji-tanccn, ih« 
kidnevfi for others, the ^kin for a thinl (^>n)>, .'ind tin- int<^>timr^i for the renuiinder. 
In thif- MTiy are eltmiiiiitwl all of tlie mnK'riaU which rv»ult from the cunetant 
weuring out of tliv body. 



Orgrans Snpplyioif NourishnieDt. 

If tliprc wen? no corn m-n ■nit ion for the destnictivc changes which are ^ing^ 
on inccKwintly, in a very sliorl time every life would ewi^^e. But just in pru|»or- 
tion to the extent of the wnslc, iinil pni>-iiai|]y ^imuiliuu'ini(-ly with it, repair 
takc!» placv. A* iin oUI piirfich- lajisi^ fronva li^^uc a new niic ■npiilies its plucc 
without delay, nvcn vin ilic rsaxVn of »n amiy, thoii^ih conitlanlly MiinV*riiig front 
the taviigc!" of ili-stsLsc, death, and dcwertion, urc kept full by tlic enrolment of 
frcwh rt-vrnitii. The jwrtaU of the body by which the new inntonals im- tiitro- 
duct^l an- tln^ rew]Hra(ory and the alimentary organs. 

First of all in in!i>i)nance is the rcitpifatorn fi/^em, which embraces the na.-^I 
p«.-«ige!i, the pharynx, the Iar>'nx, the windnipe, the bronchi, the bronchial 
tube^, and the lunpi, the Wt being the essential )>artM. But ^'onie critic olM»!rves 
itntaediatcly that the ]nng« have been mentioneil alriiidy an channels of elimina- 
tion. Very true, but they are aI»o ehanneU of approprinlton. Not only do 
they expel vile ami injurious waifte miitlcrif with every outgoing breath, hut they 
admit to thi- b1ou«i pure und KUHtaiiiiiig tinlrieiit iniLtcrial with vvery incoiiiin)^ 
brralh. Here is om- of the tifniomies of niiturc-— the wagon U never empty : 
it carrit* out the oil'id and it return.* with a hwd nf food. Second, we have tlie 
almmtari) ftitif, with it? attcndiint organs, the xativar^ ghiulii, the panntxi", and 
the fifw. This IuIm- is very long, inehidiiig the moutn, jmrt of the pharj-nx, ihc 

f:«l!cl, tJw slomiich, the small and tho large iiitestiiics, tin- hist mentioned having, 
ike the bnigs, the donliU- and conlriu-y fiin<;tion!< i>l' jippiopriiitioii and excretion. 
It i.* funiislied with appaiiitn.>^ by which .nolid food can be cho)iped, criiiihed, 
molsteaed, and reduced to a pulp, and other contrivauees which dissolve anil 
chADge the foi»d in various ways until it is in sncli condition that it can p-iss 
throiuh the w-alls of the tube and enter the capillary blcHMi-vessels and lyniph- 
veaaee, which (orm 6ne networks in the substance of itB walls. Passing into 
these two sebi of veswis by the process of absorption, some of it reachcf the 
blood immediately, and the remainder sonicwhut indirectly by way of the 
lymphatics. The bloi>d, therefore, is seen to Ih- etiriclu'tl by giiseoun material 
in the lungs and by liquids iiud li(]uefi<-d sulids in the alimentary lulw. All of 
tllciW )uidition» are brouglil by the veins to the lieiirt, and thenee arc pumpetl 
into tin- arteries. The latter ponr their contents into tin- eapillaneii, which are 
embedded in iIh* tissues. Those minute ve!V'it;lft are so thin that the nutrient sub- 
»tani-i-.s in lh<' blood can piiss through their delicate wall, come into direct 
contact with the tissne.>*, and Hoorl them with foiKJ, To each lUsne U offered 
a repast sutiwtanlially identical with that funii-ilied to every other, but no two 
of tneni cln>nse the fame articles from this surnptitous table, each having a selec- 
tive capacity for tho8c things which arc bc«t adapted to the prcwrviilion of ita 
own ]>ecnliar charaeteristici-. So, each tissue having appropnatx^'d whatever it 
a«MJs, the rc!^idiic of the nutrient nialenal is wirried away by the lymnbaticw uloiig 
willi the waste pnxlucts already mentioned. It will be ol>»ervcd thai it is the 
va'U'ulttr system which takes supplies to the tissut-t, and the same system which 
rairrit^ from them the produiis of waste. 

In iionnrttion with the alimentarc IuIm" were mentinmKt, as acecnsory parte, 
the salivary glantl.t, the |>ancreas, and the liver. Those are true glands^that is, 
organs which abstract cenain materials from the blood, manufacture them into 



33 



INTRODUCTORY. 



new aubstsnces, and discharge tijese last into cavitic-i or apon surfaces. Thar 
salivary gliinds cmptj* their products into the month ; the pancreas and ihi? liver 
pour tlieiriT into the 6taa\\ intestine ; and those tluidfi — saliva, pancFGatic juice, 
and bile — eflect certain digestive ebaiigt^ in the food. • 



Organs of Internal Secretion. 

There ure other oripin.* winch n-M-mblc true glftiuU in their general grinf* 
appcflranee, bur nrt- unlike (hem in an iin|iorriwit respect: they have no tnlxt* 
tbrougfh which their product:* can be discliarj^cd iijion a surface or into a cavitv, 
and hence they are called ductless glands. They arc the spleen, the thyroid 
liody, the ihymii!*. the suprareiiiil capsule;^, the hypophysis, the paruthyroids, and 
the carotid and coccygeal KlandH. It is isuppoeed thut they furnifih Kubi^tances 
which produce a profound impre<<iion upon nutrition, and tliut thcHC matter]<, us 
soon lis formed, are thrown into the liiood, wlienee the miitcriul for their forniii- 
tion witK origiuully derived. 

Organs of Hotlon. 

Certjiin orgntw are devoted to the work of movement. Through their instru- ! 
meittalily ninn i» enabled to t^eiice mid riliiin hiK tiiod, to defend liim^elf from 
and to a.4.Hail his eneimei4, to move about from pliuc- to plme, and to do numbi-rle,->« 
other acts iu which motion is the nrineijuil factor. The organ.* giving man such 
|)ower are mnncles. They form tno most of the hulk of the linil»s and a great 
part of the walls of the cavilics of the trunk. The lean meat of animal.'^, which 
IB a part of our food, u muscular ti^ue. 

Framework Organs, 

All of the organ.4 of the IhkIv are held in iimiably close rebilion to em-h 
oilier, nn<l are vet kept from ennvdiiig logi-tlier with iniurioii* force, by OL-rtain 
(^Iructiin-s whieii arc called Kkeletid. The nuwt strikinj; and faniiliiir of ihew an* 
the bone--, which form a nijible framework {>»• tin- viirinu^' iHirl.-<, a fltnuig proteiv 
live wall for cavities containing oi^jans of gn-at delicacy, and powerful lever* 
upon which the miLscles act. Cartilagis are unually cluM-ly associated wilh lione.>*, 
but there are cases in \vhich cartilagea by llicinwelveii [Hrform just such services 
aa bones more commonly do. However conspicuous tliese hard structures may 
be iu their |>eculiar line of work. It is doubtful if they are of more use in 
the animal economy, even in their {M'culiar prttvincc, than are certain soft, 
flexible tissue*. The fibroux tissue)- do almost all of the minute detail of sup- 
port, the Ikvuc* and eartiliiges beinp devoted only to the coarser kiixls. All 
lhniti;rh 'he organs i" a iiiie iietwork of these tiNsuec. furnishing a vt-rilablc 
i^kcleCou for the microscopic cleiuent:* of which the organs esTK'Ulially consint. 
There are al.->o siibi<tance.4 which serve »* i<(iiflitig and cn.-<lii<m-nmlcrial for 
various jwirts. 

Organs of Relation. 

Of all the organ", thoM-constitiittiigthe nervous system are the moiit exquisite 
in stnicture anil the highest in function. They arc the ftitiin, the Hfihurl foril, 
numiToiis xmall collections of lu-rvou" tissue called ganffliti, and u great 
niiiubcr of cords, thi- nn-riw, each of which has a couiifclloii n1 one end with 
fomc one of the nervous niavu-s almve niciitionctl. Tin- iiitaous iw.ateni geia 
it8 pro|K-r share of attention frtmi ihi- other orgjins whii'h liavc been 
i)p»keR of as engaged in carrying «ifl' wasic, furni.shing material for repair, 
moving parts or tiic whole of ijie body, and doing the tHiAsivc Ber\'i«e of 
framework. But it acts as if it recognised the great obligation resting on 
nobility, and it returns tlie devotion of its hiunbler tn-ighbors by servicer of 
the most exaltcil «irdcr. It regulates and harnionizc<> the <)p<'nition^ of all of the 
other jHirts, keeping them up to their work, rcntniining tlicni if u t«-iidcncy 
to overdoing appears, sustaining llw ecguilibriuni of all the functions. But, in 



I 



METHOI>S OF STUDY. 



33 



MlditioD to all this, it l>ringH the imlivMluiil inln conxcious rplaliun with th? wortd 
umuixl liim tlirou;;li (lie- iii<t<liui)i of the or^ii^H i>t' spc-i-ial m;ii»*.-. ^VicllOUt llii^ 
hut' aervicc our livvs would he |>iirely vcgetAliv«. 

Organs of Reproduction. 

Th*- fiinetioiis of th« ot^nH thiw lar lufntioni-d concent oulj- die individual, 
|>ri)vi<linj[, fiisl, for hii^ |)rii<«TV»li«>ti, »ml, Kt'oml, for his relulion to the thinjfs 
amiiinl him. There arr uthtT orguiii* — not, howcwr, in n ootiditiuu of functional 
activity during tin- wlmh- of lift- — ^which are nwicssary li> ihi- pi\'«Tviilii.ii of the 
race. These an? ih*- orgitn!" of p'm-iiittiMi. Ono wries of ihiMii is iircscni in ihc 
fetuah-, and its rhi<'f mi.^int>i-ri< art' the ovarU», wliioh fiirnUh i-ggs ; th« FulUipinn 
tuhef. bv whi<-h iho i-ygs are con<iiict«] to the womli ^ut<'nw); the trotnb \l^M, 
to wliioli tlw v^gT't 'f frrlilized, may remain during th*' |>eriod of prognaney ; ^he 
raffinfi. which recoives the penis of the male in oopulaiioa and gives |Hii^sage to 
the youn^r when the time for itn liirth has arrivcMl ; and the mamwtr, from wliic-h 
tlw pnigenv nhiain .■'Hatcnanoe for a oonMderahlc perioil. The other wt of orgiins 
Ix-hnitT' to ttt<> male, and itc princi|HiI |Hirt» are the ti-j^u-Jn-, which furnish the 
etrtentia) part of the icemen for the itnim-^nnliun vf llic cfgrs : i-vrtiiin tutim by 
which th« semen flnwB to the itrHhrri, l!io eondnit tioinmon to the urine and tJie 
leoerative fluid ; ami, finidly, tlw penU, ihe nicnilHT hy which flexunl eonncction 
IS effected and the mule pnuluot dcpo»ile<l in the female generative pu.-uuiges. 

THE ORDER OF TOPICS. 

The chapters in this t>i">k are arranged sni>stantia)Iy in the conventional order. 
KiiNl i-itniei* a brief presentation of the elementary tissues, followed immediatelv 
Iiy a chapter on emhryologi,-. Then succeecb the descriptive anatomy, in whicK 
tl)c oi^n^ are tn'ated in systems, and aiW thifi the tojKigraphicnl, which deals 
Milli lh<' relations of the different organs to each other. 

Tliat the ai^eonni of the hiF^tolugic materials coni|H>sin|i; the vnriou.^ organs 
should prevede the description of these slriiftiu-es, and that the mutual relations 
of the latter i^tiouUl not he preMruted until the organii themselves have lieeo 
described, are so loj^cally nwT'Wiary a» to ri'onirp n<t explanation. Hut the suc- 
cession of topio in the syxt^-rnatio anatomy snould be mm.k- to van' according to 
circiunfitniKf*. 

If Ihe learner !» studying nimtimiy only, the urranp-menl set forth in the 
table of contents ii» n.«ff<d. lint if he is Klinlying phyi'iolog%' at the sjinie tiin«, 
hv would do Well Mt to miHlifv the order that lit* may obtain a knowledge of the 
structure of each oi^m just before its function is considen-d. A» t>liyHitilng>' is 
concerned laigely with tlie contents of the cavities of the body, thi!« plan will 
involve the ^tudi- of the viscera, inelnding the brain and eord, earlv in the ctnirse, 
Anv hours which ore fairly due to anatomy and are not consumed in thU prejua- 
rution for ihe protitable wtudv of funelions should he tk'voted to osteolog_v, and 
alter thiH luis licen m.-isl-red the topit-s would beet be taken up in the order as 
Stated — 'joiut«, miiHclei«, lascin:, vessels, and nerves. 



METHODS OF STtJDY. 

Any work which is done aceonliiii: lo a prt-animgcd symtem i* more econom- 
ical of time ami effort and more productive of dc^inible rcMdts than tliiit which 
is done in an nnmeihcidical way. It is |>arlienlarly iniftortanl fur the student of 
anatomy to follow linci? wisely laid down for his gnidnniv, btiaust" of the limited 
time at hi^ distKusiil in which to acquire a mat-terk- of the mullitudo of fncl« need- 
ful for hi!> suWspicnt progrcsw. Sune won!* of coun»iel, therefore, an; here 
offcrcHl a» ti> the niclhoiU of mtmly which experience lias shown to be 
4idvanlageou8. 

3 



34 



ISTROD UCTOR F. 



' Merely rendiiie tlip toxt-book is prorluetivt- of but little good. Many a man ' 
who liaw (lone this faithfully k mtt'rly iiiiabk- to iiiiiiwcr a quo!^li<iii whiih 
would bp likelv to be iiictuiU'd in tli*' list iin-jHiiTd by any rwmiwtoiil bt>ard of 
examiners. The fade an.- so niiiuoroiiis, ntid often i<.o wfiTiiiigly mm-liiti-d iv eiich 
other, the naniet? of ubjoi't* art- SO unlike anything previously known, and iho 
allusions are so lr<.i|nfiit to matters which niu.t) remain unexplained nniil ii Inter 
piirt of the eounsf, ilml it i;* wellnijih iniiKi-itiible to briuj; away from a single 
reailiiifT, however rarefnl, mueh more than a ehaotic impriK^ion of tlie subjecif 
eoiwidenHl. Sonif sindentti in their deriperatiou rew>rt to ihe plan of verbal 
memorising — learning wonl for word the deweriptions in the Ixiok. It is hard 
to oonceive of a method more wajiteful of enerK.v and less fruitful of results. ■ 
One who has done this mav be able to pass a brillijmt oral or written examination, 
hut he has not bc^un to be an anatomist ; be is helpless in the presence of the 
dbiseetcd subjeet, and ineapable of using what he has stn(lie<l in any pnielieal 
way. A student should not allow' himself to adopt this metluHl. He must learn 
the faets in sueh a way that a iwnnaiienl image of every object is prodtieed in 
hia mind, and thus bis knowlcilge will be aviiilable at Ihe bedside. Uf ii>nn« 
it ia nceejwary to nvqiiire u nomenelatiire— to learn tlie iiamw of iJic object* dealt 
. with — for without X\iv*v- labels of things it is inipnietie»ble to reeeivi- infonnntion, 
to retain it easily, or to immrt it after it luis U'eii gaineil. Hut this is a vaMly 
different thing from eomnntting to nii-raory the prei'ise phriiseology in whieh any 
author, however learned and elocjuent, has frann-d his pivsenlatioii of the fai-ts. 
The eleai-er and more forcible a statement in the btwik, the Iwtter is it for ihe 
student; but, the idea having been grasped, its clothing of words should be 
ignored. The student should ne ssitisfied with nothing less than sueh a eompre- 
hension of the fact that he can lucidly convey it in hie own language to one who 
never heard of it before. 

It is generally very advantageous for the student to have before him th« 
object while he is reading Ihe description of it, for thus he is able lo verify or 
correct the aeeouul which is given, and to get more concrete and enduring idea» 
of the various qualities of the thing itself. When osteology is under considera- 
tion, it is not difficult to pursue this ideal connw ; for even if the student ennnot 
afford to buy a complete articulated skeleton, he can obtain liy a Muall cxpcniii- 
turi^ u sutlieicnt number of scjHiratc bones to supply almost all of his needs. The 
little ontlwy ix-ipiiivd for this purpose will be more than justified by the returns, 
however im|Hvnnious lie may he. 

Many of the organs c-nnuot be preserved in sitch eoiuUtion that they eati Iw 
fitudied lo advantage in any sneii way as can the Iioncs; but lus snlistilutes for 
them we have easts ajid models — ibe former repre.'ienliiig exailly ihe external 
fonn, size, and color of the originals, tin- latter in many eases doing this and t^na 
showing some details of internal slrnctni-e. Hoih easts and models may be more 
instructive to the beginuer tlian the obji'cls for which thev stand, even sup|Mihing 
the latter to l>e entirely normal, iuasmueh as the real specimens are generally so 
tK>t) and flabby that they do not retain their shape as do their artificial represen- 
tatives, whieh an- made of rigid materials and jiossess the additional merit of 
etimpiinitivc iodcstrnctibility and can he U'ied year after year without anpreeiahlc 
diminution of value. When minute parts are in qtiestitm uhhIcIs are far pitfer- 
ablc lo the real objeet-s, lis they are of colossal si/e. The pigmy organ tells itis 
Btoi-)' in a tiny voiiv which wc e^uiiiot und< rsliiiid unai'lci! ; the giant nuxicl 
shouts its meiisage in tones which u whole moniful of people can hear. 

fiutcven casts and niodeU are UKuallv not availaiiic except in nicdieal sehiioU, 
and we are consequently driven to eniplov pietnn-s, whieh, fortunately, arc to Iw 
had in such abnndanee and of so admirable (junlily that we often hardly miss the 
the really ideal means of illustration. ICvery one learns more quickly from a 
goo<l pictorial representation than from the Itest description, for the mind storeti 
up the iinprcs»ions of form and color which enter it by the channel of sight far 
more eagerly and tenaciously than it does thuso which reach it by way of spoken 



METHODS OF HTVDY. 



36 



words. WIkti- tlif subjprt u very complex, n diagram is rommnnly morp uspful 
than tbc lK-«t pictoml rcprcM'iitatiou, Locaui'c it climinaK-t^ cviryihin;; bitt \\va 
eEfienoF of Itio mitttcr, iiiiil llui» dooi not ciinfitM; the mind l}y too vimt iiii iirniV 
of fiiotis. Tin- Mu<icni, huuitviT, i>lioiiId «ru(mIouiil_v avoid allowiiijj liiinM-lt i« 
be contciil wiili ;» im-rcly diiignimiimtic knowlwijji- of any part of anatomy; he 
should Wk^ iIm- M:hcniatio picttiri> only i).< » prelixto to the actual tJiing, :ia the 
mnp wliicli iiifonn.^ him where and how to find and luirn about tlie unknown 
Innd nnd iu r»nl«utt). 

Ahitmifih de^rnplion^, diagrams, pictures, moclelit, nitd ciwbc hav« tiK'ir di»- 
tiue.l xiihie, eai'h in Us i>eculinr field, it muM never Iw forgnlten lliat after leuni- 
iny all which ihey can tca<'h it U of the greatest imiMtrtanee to have conluct with 
the mitural (Jijeet, Dissection of the dead body stipplemeatit and ntitmls «»it the 
knowledge which has been previously gained, and its service is indi.'<|K'n>ahlc. It 
is not well to attempt disHection untifone has learned by other means the prin- 
cipal facts about the part to b» dis^^votix), becitiise witliout such antecedent 
knowlcdgi- material, which in mo»t placCJ' ii» warce and cosily, will be wantetl by 
unintelligent cutting. But iincr (lie student Iiiim qimlified himself to appreeiatei 
the views whieli can Iw obUumtl tinly in \\\v analomicnl laboratory-, lie Khonldl 
embniPi.- wcry opidirtnnity (o di*.«i?ct, fur liiii:" only «in he become a practical 
anatomist. When a hmiuni body cannot be proiMinil for thirt work, the manual 
dcrximty which is .40 imjforiant an aecompli.->hmonl for u Kni^'on may be cnlti- 
vattxl by ihi- di^isi-etion of cati, dogs, an<l other anitnaU, which aw abmahini imd j 
chi-np ; and llii.t pnictict! U a mont desirable preparation for the Mndy of hnmnn' 
anatomy for other realms than the mere bkill in the use of iKHnc instruments 
which it bestows. 

Among the aids to the a<»iuisition of anatomical knowledge, two which are 
bnt little appreciated deserve especial mention. 

Tlie first of these in the recitation. In this exereiso the student is obligetl to 
describe the things which he has been studying. This is a severe bnt mo«t 
wholesome test of hb knowleflge. By it hi-i atlention U attracted as in no other 
way to the defects of hi" attainments. 8ome matters which be bad Rattered 
himself w'erc perfectly understwHl are fotmd to have Ik'ch only partiallv learned, 
and in others be diMNivers tliut be has acquiixMl mifitaken notions. The ability 
to describe a thing clearly and fully to others is a couviucttig evidence of attain- 
ment, and the exercise of it w a c»|;ital metho^l <if liii<tening the truth in the 
mind. If possible, the slutieni should associate with himself anolh<'r of the 
same class, and no day should be aUowed lo jwiss without a s<-riou.s, exacting ijuiu, 
the two alternating in the oRiix- of ()Uir<tioner. 

Vahiabic us are the quix ami recitation in correcting and inoreatung one's 
knowledge, (hey are ulin<i^t cqitalltHl in these ret>pectH by drawing. Sight and 
touch give an excellent idea of the form of a bone, but the information gained 
by theM- mi-ans U greatly intensified bv making u free-hand picture of it ; and 
in the proeeK-- one is almoiic sure to sec features which were not previously app«^ 
eialM, and to n-ctify some faulty opinions. The same is true of all other objects, 
and the student is earnestly advJseil to make a drawing iif evcrj' one of his dis- 
aections. If the natural objecis are nut avaihible, he should ilraw the easts and , 
models which ho lias the privilege of studying, ami, in default of better rcpre-J 
sentatiims, even the pi<;tures in liis text-ltook. 

But the objection is a1 oiiw raised tlint only a few peculiarly gifted per*on« 
arc capable of ilniwing. It is not nnconunon to hear men declare that they «m- 
noi b-arii to 'Intw. Tliis slatf-ment, however, U al^^urdly incorn-et, for every 
such objector nm already write, and writing is nothing but the drawing of certain 
arbiCciry eharaet<-rii. One who makes a capital A can surely outline a tent ; if 
he enn nuike an S, he can draw a wi-iggling snake ; in forming an X he has 
p!etnrt.-<l a St. Andrew's cross : and thus evert' one who signs his name demon 
strafes hus ability to draw. The talent is undoubtedly mon- marked in some 
per^>ns than in otherv, but is possesse^l in some dcgrei- by all ; and, however 



36 



JNTRODUC'fOli y. 



•light it mav be originally, it can he cultivated to aiwh an extent as to be vonder- 
fully serviceable to the medical student. 

Although the few siK-cecding panigrapha are not Bpocilically anatomical in 
t]ieir bearings, they huve u pertiiitfiicv in tliis ptaw hecauw evary medical student 
at the bcginnio": of his career should be given tlie iidvice which they curry and 
which he \» unlikely to find cl>fw Iutc. 

Among the article;^ of i-(|nipiMiiit which a mediud Mtiidcnt needs nouc is more 
imp<^>rtuiit than » goorl medical dietionurv. It i.* an indisin-nwilile. If he ignores 
itK aid, III- ifi <l<K>med lo fttnnihle and bUmdcr in even,' diriftioii ; if he accepts 
(he aHslKtiiiicc ivhi<-li it will give for the asking, \w can progress resHlily and 
vigorously in all the [wilhs of medical study. 

A intflical dictionary, in order to be thoroughly ser\'i(M?ahle, ought to |X>«»es* 
the following oharaeteristicH : The inclusion of snbstantially all of the word:* 
enipl<iyed by the English-writing medical authors of the time ; tJie armngenient 
of these worU in aTphal>eticaI order; tile various accredited spellings of the 
words ; the proanneiatiun of those words on whose orthoepy one might go astray ; 
the etymon or original form of each, and the simplest translation of it; and a 
concise definition of the worI in eneli significtition in which it is employed. 
Several lexicons constructed oti these lines are availjiblc, any one of winch will 
do good service; but one which is luss ample will not Htttsfy the ruisonabic 
requirements of the student. 

Although the so-failed Uomiin pronunciation of Ivatin i* genemlly taught [a 
the sehiHils and colleges of this ivunlry, the diclionancFi, for snfJieiciit n-iiHi«s, 
use the English pruiniiictiition of the liOlin anil LalintMHl woiii-' whieli form the 
princijnd pari of the vociiliulnry of nie<licine ; and this method is recommended 
to the student for liis ;idopiion. 

The ;>tndent is earnestly advised to a'itablish the hahit of consulting his die- 
tionurv whenever he encounters a word whose meaning he does not know. He 
»hoiiI<i fix Ihe siH'lIiiig in mind, learn the definition, ohser\e and remeniher tlie 
dcrivHiion, iitiil repeat llie i)roiK'r pronunciation until the tongue has fully mas- 
tered it. Finally, he will do widl to ascertain the kinship of the word, if any 
exists, to other words already known, and to group these all together in his 
memorv as relatives. By tliis method he will rapidlv acipiire a large voeabnlaty, 
ihe abilitj- to employ words with strict regard to their meaning, to spell correctly, 
to pronounce elegantly, and, as an iiceompanimcnt and result of this training, he 
will he cimtcnt with nothing less than precision of thought. 



ELEMENTARY TISSUES, 

"AND THE STRUCTURE OF MEMBRANES AND GLANDS. 

Bv P. U. GERBISH. 



A FULL pns^nlation of micnwcnpio annloray wmild iw|iiire a larp- voIiim& 
It U tlio iitiiiii [niqiiRir- of tliin olmpler merely t4> giw n liriof (U-^<'^1)ti(>ll of 
(III- fli'niciitarv liMSixrs uliicli enter into the formation of tlte ImmIv. ^Vill1llllt n 
kni)W it\Ipo of tlnw«- iiriniary lextiires riiip)i that must be sai<i of tlie jri'o^s anatomy 
of (li(feri-nt [xirti* will !«■ unintelligible ; iwleetl, it is impoMiiblc to iindei^taud any 
orfrau, eitlit-r from the nnatomicnl or phyeiolugical point of view, urile^ the inate- 
riala of which it is composed and the various physical projioTtiee of these sub- 
MtaiieeH are known with perfect familiarity ; for tlie tissueH are to the oi;guns as 
the letter*- of the al|ihabet arc to wrilten words. 

The mintitc strucliirf of the visccm will be dt-scribcd iu conuvction witJi l!io 
mncru6copic features ol' eaeh organ iu turn. 



CELLS. 

Tlio word "tissue" ineanx, in ordinarv pftrlniiw, n wcb-likc structure or a 
wnvcii fiibrie. Anaomiially, it U applied to any urgani/ed siibi-fnnce in the 
body. Notie"' (liat in ibis dctinition the word "orgtinixtH]" t^ iisi'il, not "nrfpinic." 
Ttx^ Iwter wonU), indeed, exclude the Aub^tanifii which are inoi^nic — tliai is, all 
of the ultimate etementu, of which there are many in the body — leavinff iheni to 
the con.tideration of the chemist; but it would include quite a iiiimlM'r of sub- 
ataiMres found in the body which, although organic, have no title to he called 
atrticttirft*, and belong in the domain of the physiologist, who deals with the 
proximate principles. Thus, albumin and fibrin arc ort::ii]ie siibstunees, but not 
organized; and, consequently, they are not tissuwi, for tissues are always oi^gan- 
ised. 

Every tissue oripinnlly consists of microscopic giarticlcs, iiame«l "cells," 
which liavc liccn aptly called the eimplc'l expression of tissue. KlyniiiI<)ptotlly, 
the won! "wll" i« an iinfurtunati' designation, Iwiscd upon a miMuken bi-Iicf us 
to the slnicUire of (be curpuwle. At fin«t it wai« thought that cell.* wew cy!>r|i<, 
mo, vesicli---, with tUiid i^ontents. Hut it was long ago horned that ibcy are 
iLiiuilly solid b(KiieJi, and hence a wonl whii-h implies tlie exb*t*-noc of a oavifv, 
as does "wll" (Latin, eefla, "a Hnuill, hollow cavity"), ia a miwiomer in the 
majority of casps. However, the nubstitutcH pn>i)aied have not met with general 
fsvor, and " oel) " has become so lirmly fixed in our nomenclature that we ^hall 
not attempt to diiiplaec it ; in4lec<l. then' is no call to do so, sincQ no coafltsion 
□ecd arise from its use )u this arbitniry sense. 

Not only is it true that all »f the lisMies primarily are composed of cells, but. 
coiug buck miieii farther tlmn ibis, wc reeugntw- the origin of lh<- entire body 
from n single cell, the ovum (egg). This enforces the soying, wliicb Iiiiw iH'come 
■Imoet an uxiom, thai evc^^' cell comes fn>ni a pr<--cxii«ting ml. 

3T 



38 



ELEMENTARY TISSUES. 



if ft-iu, iiitit wiiicii 



*t 



ct U thf wfti- 




Fia.7, 

II.GO 



DlagnuD of ■ celt. 



Of tliL- luimcitniN ilcfitiilioLi!? 
mrilr morithol'it/iiiil i-U-ninitii of the titumtv. Ii ix mil. tstiHicicni t<i mi\ llint llicv iiro 
till.' " iiltitimlo fli^iiiciils " of (lie tisnms, iKs-aiiwi- tlinl U-nu ivlt'ix Ui ihcir cliiiiiicul 
viiiiiitiliiciii.-> : it is lu-ct-ssarj- that tlie di-liuiiiun nlioulil indiidt' a vml which 
I'xiilaiiia lliat the rlcnioiita rcftTit'd to have a deliniit?, di^tinguir^hablp, and tharac- 
tcristic shap, and this ivqiiircmeut is fulfilled by thf word " moqiholopcal," 
lht> ni^eulivc from "mor|»lii)liig\-," the stienco of form. Thus is ronveytd the 
idi'a that in histological iiiialysiis — which is to the rui(^rosc<j|>ic sti-nctiii-cs what 
dinricction is to the muiTo«.-o|iic — wc do not po beyond the cell ; lliiit thi*^ h the 

lust thins rciii'hcd by the pnwctis ; and ihiil in all of 
ihc tcxlnms i( hsis such dctinilunt^^ of form as to fu- 
nhli! Ui* to difttTciitiatc onv tiȤuc from unothcr. 

The tyiiii'id «vll (Fig. "), ciifwddc i>f dovHopmcnt 
and nMinKHiclion, i» a round or uvoid ni»w< of prolo- 
[iln.'^ni in nhich i.^ a nncl<-n.-<. 

I'mlojt/iimi (f'niin (iri-i-k wnnls nionnin]; " the fir!>t" 
and " the thinj; f<n'ii»-d ") in ii f-nh^taiH'c whose projicr- 
tiwi underlit- the vital fnnetionw, and thereforf il lias 
been called the jihysieal basis (if life. It is lionioge- 
neous, soft, and jelly-like, and jwsscssos contractility — 
the power of shortening a dianutcr. of drawing one of 
its jmrts nearer to another. It usually looks graiiiUar, 
but this appearance will be explained n little later. 

The nucteu* is a roundish mas*;, pcnernlly central in location, and named front 
the Latin word which means "the kernel," Iwcausc its situation is so i^uggiL'stivc 
of the meat of a uut. Sometimes ihe nnelcuii contuin^ ii snmll body (]KTlmi)3 
more than one) beariiifr to it. a relation similar lo that whicli itie nucleus itself 
suHtiiiii!^ fo the cell; and this is called the uw/rntuH (" tia- little kernel"). 

The typical cell hns no invcstiiij; nicnibriinc The f^niitiilnr «|i|H^iniiicc of JW 
pix>1o[>lu.T<m is due to n network (fiiouifutjilimm) whicli l)i.s-.onie> visible with Icn.tes 
of high power, [n the meshes of lliis plexn* is n neiirly tttild, hoincigcneoiis 
malt'riul [hi/ahplfmn). The nueleus has a similar crtiistrmtion, but has addition- 
ally a limiting membrane. The nucleoli are conneeled with the rctietiliim (net- 
work) of the uneleus. (^)ne point on the niicleos is called its jwle, and the exactly 
opposite i»oint is its antijxde. 

The protoplasm niay become condensed at the surface, and this hartlened 
peripheral part is called the cell-wall. A deiMisit of chemical substances in 
the wall frecjnenllv ot-curs, and c'ontributes to its solidity. Cells may produce 
niutcriul superficially in large amouutr^ williout cssi'ntial chanpc of their own 
8hupc ; and thuf^ arc formed snbstanee>- culled intercellular ('" between the cells"). 
Tissues consist, of eclU and iater<ri-IInlar sub.rlnnee. In sha|>c cells dillvr widely : 
Uh* vurioiu foniM will be describwi in iimneelion with the <lisciiN«ioii •>( the 

respective textures. Siinic I'clls are Icwt 
than jjVj '"'■'' '" diameter, otlu-iN more 
than jjjf, and betwtwn these extremfs are 
all possible gradations. 

As has been said, the protopla-ni of the 
cell jiossesscscoiitractilitv,andtliis proiierty 
enables It to display movements which are 
known a^^ amfeboid, because they are ob- 
served in a lypiwil form in a unicellular, 
a(|unliu creature enllcd amaia. In its 
amccboid movements (Fig. 8) the cell altera its form mpidly, assuming indi-- 
Bcrilwhly fantastic outlines, due to the irregular (^)ntraclioM, first, of om- portion 
of liw mass, .ind then of another [Mirt, By virtue of this (luality the cell can 
move from pla<^e tii place, one [Hiint beeoming fastene<l, and the rent of the i-ell 
moving up to it :uiil pushing out a prow-w to a farther point in the same 



I 
I 




tvt. f.— AniMbald moieinviita. (Uickcl.i 



CELL HKPJiODUCT/OJV. 



39 



dirprtion. Thtt> ia aorounte<l for the miBnition of cells from lilood-vewcli>, and 
tb<-ir w-andering troni oiie ]Kfint n> iinotlifr oiitjiidp of th*? v«weU, 

CELL REPRODUCTION. 

TliP formation of now nAh is aw»i)jjitinln-d fiy diviiiinn nf fild ccllg. Th« 
diiMl mctltod, by which every elenient of a cell woa ec{uallv diviih-d hy n traui^ 
verse conMriclion, was fonnerly i^ii(i|K)^>d to obtain gcnprally, but i.-< iji«v kiio>vn 
to be very rare. The iudirert plan of divi»-ioii is alaio^t, if not nuitc, uuiverBiiI. 
Bv this raetliod tlie nucleus uittlvr^iH-M u m.-ri«; of complicated modilication.'), 
whii'h, taken as a whole, arc callcil ifiryohinfiiiii, a nutnc derived from the Greek 
vrorihi for "nut" and "ehai^," the t^ignilicntion of (he compound bciu];"tbe 
cham^ in the kernel " or niidciM. In .Tiiuilyiiig the detniU it im well to hear in 
mind tluil in tlii» prmii^iw, wliich !.< thr prim^iiial movement towiirtl the cmition 
of two ivlU onl of one, llivrc ot^cnrs Kticli it division of (lit.- <.i-ll-|iix)t<iphi>n) and 
of iIm- iiucIl-u* tiial t^-li of the new-horn ectis inherit.^ a half of every jKirlion of 
llii- jMreiit-f^-U'.-i eiitatc. 

When divJMon i» about t<i take place the nupleiia imtieeahly <>nlargn< (Fig. 9). 
The nuclear membrane and the nucleoli disappear, and the i>eiY>ndHrv filamentm 
■of the reticulum arc drawn into the primary threads, makinir ihcrn tliicker and 
morv wmspicuouH (Fig. 10). It is not positively determined wnether ilicric threads 






Fiii.lft— Sm-li'oll Hiirl guiL'oni)' 
arr nlniDcnti hitn dlHpncom]. 
IKILO.) 



PlO. II,— Thn nplniUv lUl^ V 
loop*, Bldo vlgw. (K, U. ij.) 



1^. v.— NuctrU' ri>lu)(r>l. Tbit 
bgalgr oS ib« «n to rrtimrtilvd 
ncmr in oullinu la UiU wrtn «r 
41a«nn. iF. n. <) ) 

all imite and make one, or arc ecpanitv ; whichever is true, tlicy form a peculiar 
and eompiicatcd tangle which is cidlctl the «lcein. The diugnmi does not attempt 
to <lii?|ilwy nil of the lortiioHtlics of the xkciii, -m they arv raihi-r confuting. Then.- 
imw HpjM'iin* a skeleton fjiimllr (Vig. 1 1), fi>rme<I of delicate lilaini^ntii of the inler- 
antitial -■viilmani-e, pla«-<l with one exlreniity lit llie [K>!e and the other at the anti- 
IK>h'. At each end of the fjiinilli- librils of the protoplasmic network converge 
and produce the appejimncc of ray.-i^ At the next step (Fig. 12) a number of 





Fk. kI^VImi|w, CDilflr*. iF. H.OJ 



nn. l&~Df»iithtvr louiB. iiiiil vlww. (W. H. 0.) 



V-*hayK^ loonfi are ob»ervcd in pla«> of the skein, these n«ulting either from the 
hrenkii^ of the single thread, on the one iheorj, or, on the other, from the plainer 
nu»nife_-italiou of the always separate threads. These V-sbajied i)ieoe!* an- sh<)rt 
and tljick, and marshal themselves around the equator of the spindle, with apio» 
t« the Cfntre and limhit outward, jtrutlucing a star-like appeoraacc, which is 



40 



ELEMESTARY TI.^'iVES. 



eomi>tiiiw« c»Il«l the wrmik. Simiillaiu'ouslv witli iImk nimointnt iIh- loops are! 
i>[>lit lcn^tl)wii<e (Fi^. lit), ?o that ench orij^iiuil (or iiioiht'r) Uttip if ma^lc into n 
fdiir of stuniHtlaiy (or duiightor) hnipH — a mo^l imjmrtaiit |i!\rt of (he (icries of 
ohimgi'B. N<rxt, tin- twill sisttTi^ in each V-hiiaiiti! loii|i tiini inv:iy i'rimi each' 
iitlicr, oiip niovini; iiiT lii'ini towjinl tlit pole, the otlit-r lowai'd tlu- iinli|»>l(.', their' 
Umhti beinj: iiitfrlwkcil (Fijj. l')- IVwiitlv ihvv sepnnilc enlircly, iinil nufrrate 
to pole and nnti]>olu n-sjH'ctively, Imvollinf- along the line*' of tho .'•[tindlc, which 
«(!em to Bervc a* guides Ii> their niovemvnts. Arrived at their deMination, eiu-li 



■ad 





of diiiehlcr loop* IoitiirI polv 



Fid, in.— AttIviiI <>f JmUKlilur loop* at nul« i 



forms a Mar (Fig, 15). Now, a» far as can he seen, there ha« been acooni)tlishe 
an ci|i]al partition of the original i-eticiiUim of the niicleii)', and the nia-i^ dividi^ 
into two inafspf! which arc hcnccforih distinct nuclei. In cacli <if' thc>c two bod- 
ies there takes place a reverwil of the steps with winch the karyukinesii^ was 
inaugurated : the V-shajKnl Imjpa of the j-\nn dunjpile, their limits stretch out 
to the opposite side i>f the nucleus (Fiff. Ill), and the f-kein-like amicanmce is 
observed. Then branches are put forth from the innin or primary filanients, and 





Tvi~ IK— Dlrklon of nuck-i» Inio tiro nuclcU and 
•kuKiLiioti or V looj*. ( K. a. H-i 



Fm. 17.— ltt>>|iticiimiccr of HCnnilary lUuncnu uid 
nucluull. MvWoiiof entire ceU Into two, (P. H, ■•) 



form the secondary filainents necessary to complete a network. Nucleoli eonie in 
sight, mid a wall is formed ari)tmd the nncleufj (Fig. 17). liefore these I:lsI slajrcs 
arc nivom pit "lied the protoplasm of the cell allows a eoiistrietiou which rapidly 
dce|K'iis, and continues to increase until the cell is bitten in two, each part being 
fiirnishtxl with ii |HTfcct nucleus in whieh is no sif^i of a spindle. It is held by 
wome luitliors that the wall of the niwlcus i* not <x»nipletc, and thjit thus is pcr- 
niittcil a niin^ling of ilie interstitial .■'iil>;<I«nec of tlie nucleti.s wilh the <x-lhproto- 
ptiiKin. However thi.-< may be, noluKly tjue^tions th« intcreonitnuniuition after 
tiie disapiH-a ranee of the nuclear wall. 

Various modifications of karyokiuesU are frequently ohse^^'e^l, but tl>e fypc- 
goinK description tiompriscs the main features in a typical and complete ca»e. 



THK EPITHELIAL TISSUEH. 



41 



CLASSES OF TISSUES. 

I. Tii^uei) fdniiiihinj; tli(> free MirGuvti of l]te IwHty : Epithelial Tissues. 

II. Ti^iie^ |KLisively MipporiiDc; other [Nirttt : Sostentacular Tissues. 

III. Ti.tiiuc.-i periVintiiii^ a niitritivt- fuiicttnu : Liquid TlBsues. 

rV. Tisftww devoied to niovL-meiit : HuMtilar Tissues. 

V. Tiiiwue» «8iicntial to sensation : Nervous Tissues. 



THE EPITHELIAL TISSUES. 
Tt98rES FrnMSHiNd THK Fiif:K SrRKAct» of the Bopv. 

Thore is a peculiar iiruprivty in liiKutkine of t)ii'« t^Iii^ f\nt, ox it is <.>omposed 
entiirlv of wlU, uihI aN" V'cjiii^t! th«r tiiali' ami roiiialc "■IN. by wliusi- union 
every fiiiniiin iH'inf; ii< i-ni((<''l, urc, to nil inicni.'* ami [Mtr{KL-<i-T>, cpitlii-liiil oelU. 

On vvvry smHaoi! wliicli is free, a.-* diHtintrni^hed from attachotl, nrt- found 
mulUtiiilt^ of r*!!.-*, and witli lisnlly an e.\«?ption the wirtiicesi are w)ven-ri uilli 
them or, more projwriy speaking, completely composed of them. Thus, the top 
layer of the skin \» made wholly of cellft ; so also b the exposed surface of every 
cavity, tube, or pn-tsa)^ which cnnneela directly or indirecilv with the skin ; as, 
for example, the alimentary (iinal fmni mouth to anii^^, all of the nir-passage^, the 
iirinan' orjpjns, the (lencrative ways ; the suHiivp of wivitics which are entirely 
closed, which eanoot he reached without dls^e^^lion, isnch «,• the plenni, the In^trt, 
the blooil- vessels ; and others which newl not now he eniinKTHttii, 

Thtwc cells, thus spread out in close eontuct with e«(rh olhi-r, t\n- i-pUMfiil 
cc/Im, ami the sheet of tis»tic which they form is <in rjiltJuHiim. VAyniuhiay iU>e* 
nut s»gjic«t the oharacler of the tis»nc, the c.\tent of its di.-<lril>nti<)n, il.-< n*i-x, or 
any other valnahlc Giet alwiit it, the word being tlcrivwl from the (.Ircek w<»rd» 
(^tpnifvinfi " iiiKin the nipple." It is iK-st, therefore, to employ it in ii iH-rfcclIy 
urbitniry way, Many gr(>ti|Kf of thew wlis — iudi-wl, all of those which limit the 
Mirfaoi-.H of Khni .■♦ac;^, ?hnt luiios, nnd other cavities which are not directly or 
indir»>tly c<)ntinu<Kw with lh« tikiii — arc cullwl ow/trfAf/w/. and the sheet of tissue 
which i.4 formed hy them i» named an fmhilhfUitmf the derivation ^i^'i'm >* '''^ 
meaning of "within the nipple" — a term which lias not even the niiunte Jtn'ti- 
fication to l>e accorded to "epithelium ;" for then> i.i opitliclinm npoii the nipple, 
but there is no emlothelium within it, esecpt as there U in every part which con- 
tains blooti- and lymph-vessels. As Macafislcr most pertinently says, "The di.*- 
dnction between emlothelium and epittielium is not always either hi.<itologicalIy 
certain or functionally possible, nor ean its development be relied on &« a crite- 
rion." It wwdd be well tf the attempt to keep up the distinction were abandoned ; 
but, lis «>mc writei* still employ the terra endothelium, it is well to nnderstand 
tltal tliev rvfer to a wllnlar tissue which develops from wliiit will presently Iw 
d<^Til*txl iLt connective ti^*ne. In this hin>k all such will be included under tlw 
head of epilheiiuni. 

Originally all epithelial eelli* are nucleated : in nnwt of ihcin the uucIcua cjin 
be demonstratcHl at any nta^- of their c>ci.'<tence; hut in i>onie it Ix-t'omi'n oblit- 
erated, usually as the rtwult of pres.-*iin' or exjMis.ure to th<> drj'inj; cffii-ls of the air. 

Tiie cells almost literally consiitut*- the entire tissue, the inti-rccllular ^ubstint* 
Itciu); n-ibiccd to its lowest terms, and consisting of a minute ([iiantity of a semi- 
fluid, ailhesive maleriul called the intcrntiliul ctTnc)it-«uf/g/anc«, which glues the 
celU togetlier. 

Csually un emihelium reslif u)K>n a tntnspnreiit, structureless sheet of extreme 
thinncw, nilher ditliciiH of demonstnition, the ninii/triina propria or baaenKnt mem- 
brimr. ThoUffh cailiMl slnielun-ics.'*, it i.» shown to he made up of Hatteneil ])iates 
of lypteni connective ti»»uc, uhich will Ik- tn-at«Hl of U little iuter. 

An epithelium contain.4 no blood-vessels and a very diniiiinlivc supply of 



42 



ELEMEXTARY TISSUES. 



I 



nerves. When dsfitroyetl op in any war lost the cells are pc(tenerat«l, ax a rule, 
with rapidity. 

Kt>ttlK-liiim pcrformit many im]iiirtunt wrvicc^, umonf; whid) may be mcu- < 
tionttl till' ])mtoi!ti<jn wliich il t'liniishc.* lo nii(U'rlyin^ li^wtioit, the prcv<Mition of 
\\\v vjWi\w of )yin[»ii f'lxiiii (Ik- ]uirti< vvliioh il onvei^, tho nlworptian of noumhing 
mntfriiil.t into tho Uhiod, the tiiiiii)tonancc of motion in the fluid whioh comes in 
contact with i(, the Piiionthne.ss whirh it imparts to -nirfart's, tJie formation of 
Bccretionri, and fts*-istance in the apiirecialion of c^-rtain sensory imprewions. 

The malerials eompoeing epithelial cellf. and the (^uhwiaiice unitioK 'hem are 
BUfBeieiitlv yielding to permit L-onsideraljIe alleralioni. in their form ^vithout 
iDJiir.% Thuji, when the striietures upon winch an epittielinm ret^ts enlarge or 
contract, it readily aduptf> iti^elf to the chaugitl cundiUouit, witht>ut cruoking in ttic 
one oise or wrinkling in the other. 

No oliiis-'ifiaition ni' i-pillKliid etdU i-^ very sntisfatrtnry, but the slu% of ihi-m 
i*niade>onii'«hat ejidier by the knowledp' ihiil {exei'ptingn few — the r'|)hen)i<lal — 
whcwi- furin pri-.M-wt!« but a slight dejKinuri- from that of the typieni I'tll) they may 
bi- plm-iil in iwo oin-ises, in one of which they are long and fliiidcr, and are 
arrangixi with their chief axis |>crpeiidieular lo the .Mirfaee, and in liie oilier of 
Mhich they are broad and thin, with t)ie long axis jmraltel witli the smrfaw upon 
which they rcwt. 

In the linst clas» — (Ik- eell!« standing on end — arc columnar (cylindrical), pris- 

moidal, conoidal ipyramidal), pyriform (pear- 
shaiKHl), clul)-i-h:ipcil. fn^iform (^pindle-^ihaiKd) 
ccll!<. In the f-ecornl claee — the eell;^ lying on 
side — arc flattened (ifculy or Htpuimoiiis) oelU ■ 
(Fig. IH). ' 

It will 1)e obi^rved timt thix cWisilicnl ioti 
is hnsed ujKin form only, and that the differ- 
euop between one and another iii accnunteil for 
bv the dirc-etion in whteli jinw^nre i.< applied, M 
\m examplt', rmpjintie that a large numhcr of ■ 
soft, globular cells are placed n{H>n an even 
plane, fide liv side, each just toncliiug every 
ru.u.— rUHcnedcpiibpiiaiwUi. tiwwn.i niimediate neighlior, and imagine that an e^jual 

nnmher of exaetlv similar cells are introduced 
additionally upon the Htme area. Of wmrse (ionielhing must give way, or the 
pro]»wd jhrcblcni has no eolntion ; and what actually yields 'm- the shajR' of each 
of the pla-tic cells-. The cell cannot go downward, for the surface upon which it 
Tv-Xi- ))rcvcnt*i tins ; tiidewisc pressure of every adjacent cell deprives it of ii con- 
eid'Tiilde part of it* former nlandiug-rooni ; and. »!• its bulls reiuains niudtcred, it 
i« obliged lo move H ]mrl of its mas.* ttpwiird, and ils IVit- -suHui'i', rrduci-d bv the 
lalemi scjuer/ing. \* ihrusi two or lln-ee tiiucK a-" far from its atiaehetl surface a» 
il WHS originally. The wll has lii'conii' ilonpifed, cliaiigid from a .-phere to a 
cylinder or column, by pressure applied iu :i ntnnber of lateral ."lud (Kirallel direc- 
tions. If the surface ii])on which the i-etU originally nsletl was convex in everjr 
direction, instead of flat, the cells would l>e changed from spheres to cones or 
pyramids by pressure made Uiterally on each at many points, and j>n^ rets! vely 
incrcjij'ing in force from the part nearest llie surface downward. The difl'ereiice 
iu ri'j'nlts ilciH'ndc u|hui the variation of the Mip[>oniiig Mirface. If the cells are 
]>rfn*ed bctwi'cu two piirjillcl phine*, one of which i>f the Mirface up<iii which they 
nvl, the residl i.-< u liatt.ned eell. It is easy to imagine how the other and less 
ooraniofi sluitx-ji have been ttvolvcd. 

Flatteneil epithelium is often cttlled le,*sellnled, or pavement, berause, wIh-h 
<H»e looks din-<'ily down U|>on it, it presents the a|)peamuee of » flagging of 
sloDeft. The names, however, are olyectio liable, not only because tliey an- super- 
fluous, but more iK'cauae they arc coually applicable to the cutumnar varieiv 
wbeu it is vieiTi-d in the same way ; tor the flat, free ends of the latter look just 




I 



THE EFlTHEI.fAL TISSUES. 



43 





V much like a [Kivi-mciit — iiHlved, nn> bVvu more iiii^KMlivc of one tlian arc Ihv 

oUi.-r. ( Figs. lit, *iO). 

NN'hili' these olassei) inoludc Dearly all (-[>ittielial cells, msiiy ccIIm have peca- 

Itaritie^ wbich arc dis- 

tingniiihing, and it u 

cnovonieot to dctu^nate 

Mwxa bv di?s«riptivc 

Bamvff, such as riUalM 

and prieife, fruio ibeir 

append&cv* : M-nmry or 

nrtwx*-, fimm tlu-ir rela- 

tiiKi to ttiv |KTi|tl)ery of 

a »pB«aal-s«!it-«e organ ; 

pigmattft, from their 

ctiliiraliiHi ; f/ohtei or 

c/uilirr, from tht-ir mod- ^ fip, ia--Enii *i»w of » huibIw «( .pt. ri(i.M.-tti!pTirw(4Kmo 

..,.'„, , tovllKleHu.pm«iitna(b« appt«nDv« or flrthrerlliof J'ls.iv.kfaawlat 

mcation ol nlmiK ; Inm- a parcmeiit. (Kouliu!) ihM tiuy •>« Ions •■■'1 ■■«■>■ 

«a»n«/,f»«m their beinE '^ "^'""•' 

of a rapidly var>-inji fi>nn; rjlnwluliir, trom their work in iwcrution. A brief 

ntpnlion of the chief |Mtinl.i of carh variety i.* desirable. 

Ciliated cella [Vi^. 21) in man iiro aluiiys of the iN)lumuar form, nud arc clui- 
tacteri/til l>v the |>nije('tion fmm their frep extrt^mity 
of n nninlwT ^>i deliejite proeesaes strongly suggestive 
of eji'lii-lK-!^ and henee called ciUa. The cilia nave a 
oiniitant vibraiiitg motion, nnth a strong stroke in one 
din^'tion and a weak one in tlie other. They are sii- 
uatt^ in various partfl, but never where tlicy are likely 
III lie sniijeclefl to hard usage. Thns, tlicy are nowhere 
in the alimi-iilarv tract, where the masses of fowl ami 
excrement would injure them ; hut they exist almost 
everywhere in the breathing jMisc^ges, which transmit 
oothing hurtful to them. Their more ]iowerful stroke 
\s always made in the same direflion ; tliu!^, in the res- 
piratory tract it i<? invariably stieh that the rnncu^ which 
*mcai> the siirfaw is moved toward the nm-ii end of the 
iiy>-tem — thai i?, from the direp purls of the limg to ihi- siiHiiee nf the body. 
Cilia an- found in Uie lulull mainly in the urguns of breathing ami those of 
gftieralioti. 

Pikkle-c«Us (Pig. 22> exist in the middle layers of the stratiRed epithelium 
of the e|>i<lennis, the outer layer of thf skin. They aiv i»oly- 
hedral. and ttte littK' simeen l>etweoii tlieni are bridged over with 
dt-lieait' ihri'ads, which break when the cv\U are sepanittd and 
present the np|>enranee of short, ngi<l t-piiie^. 

8«uory cptUicliiuD. or soam-vpitiieliuin cells (Fig!>. 23, 24), urt^ 
^timl in chwc relalinn with the filamentous terniimiln of the 
ncrvw devoted to taste, Mnell. hearing, and siglit ; from whieh 
foct the names lu-nnori/ unt\ iirarif- (" iii-i-\i- "j arc derived. Siieh 
A pell if iiitiuuili'ly iiK>oeiiit''d at its alt.-ieh<'<) end with the periph- Firi.ZL— ftivkU- 
t-ry t>f a wnsilive iU'rve, and at its fVi-i- ■■xtn-miiy in <pnte gen- ** 
(•nilly pn^longi-d into a stiff, hair-like pnxvss, whieh may proieet beyond the plane 
of till! surnitmding surfaw. These distal bristh* receive a shock from a wave of 
the fluid into which they protrude, and (his rauses a thrill to pass through the eell 
and 1" agitate the ner\'o- filament, which carries (lie impression to the nerve-centre. 

Pigmented c«lU are found in varimis <-!tuationn. They are of did'ei'ent shapes, 
generally very irregnlar. and have Ix-cn invade<l by fnerbaps filled with) black 
jiarl ieli-*. In ihc eohmil rsiees the lower layer* of tlie epithelium of the skio 
arc highly charge*] with them. 




Flo. SI.— Two MooliU *w- 

tlicllal ocIU. Uiirlr true oiid* fur- 
iiiilivd wlUicUlm. 





44 



Ef.EMEXTAUr TISSVE^. 



Ooblet or cbalice cells (Fi^. 25) arc n nnHlificiitioii of tlic cvliiulriciil i)r 
cnnnifliil, .-iihI rtu'ir iiiinu-s .uiv (■xp!an;it<}ry ol' llii'ir tinTii. Tin- iiuclfii« ii>tri'iit» 
to iIk- ntt:ir!i<;il iiiil of tlio (ill, ami llic rcrtt nt" \\\f ii-ll Imisuiii-> Dllc-d ivilii it 
granular malerial. The (rnmiilcs flwt-ll, i-aiiMing the |niil in 
wbUli tilt V are Loiiliiiiied to Ixilge out nt tlio nKlc- iind irowd 
over into the tirritory of tlip ailjaocnt cells ; nml, fiiiallv, ilit' 
iriti-riinl pressure bceomp* so groat that the rcll biir-t^ at ir.t 
fn.-!' vm\, il» "jiitciUj' iscaping uimn the «iuriii<'e as a triairy 
MiiIjstaiKv railed muciut. A gohUt-ct-ll, thtrcforc if^ a mie- 

eclli'il plariil. doinjr real wen-ting 
work, fi) the Iriic iiiiifoiis gluiuls 
lh<^ r'ccrfliiig (■(■IIj' nrc of this vnri-j 
ety. A gobTiO-Cfll may toon rdii 






\Q.e 



9'9\ 



FlO.»--Ni'Uft>nilthrllnl 
celli. Three c<-11> iinijL-cl tji- 
]r<mdtlWKi-ui.'ln1»irtiLi'i-, niiJ 
Ahs fiLlpuiarlvil Tiy itili'nu*}- 
ilUlc tvrtg. (ri«r.) 



Kio. M, — Nfuro • (pllhfrlW 
ci-]ti. Two tend lodff proce»i;fl 
bi'viiuil tlii: ((ciicru nurfaec. 



Fir., ■ri-lii..l.|il-. 



■ niia'-dbJCTk, 



to the condition of an ordiuary oylindrical or conoidal cell or remain a ehali 
for a long lime. 

Transitional epithelium (Fig. 2C) piirtiikt-s of 
groiif)^. It!' typical llliistnitioii occnrv in the bl 
w (xmiposi-d of tliiek, llutteiiod cells, with dim 
whieh the large eiidpi of ])car->biip<-d cclli- of 
Hjtacos Uaweeu the luj-t being iilkil with the 



the features of a number of otbc 
iulder. «berc the fiiiHTlicial layer 
jiles on tbcir under surface into 
the next layer are ri-ceived, the 
nvcrlit! colics of the lowest set. 





^ 



i- 



?lo, 3*.— Triilumon«l •pltheHum. 

No two layers are alike, and 
H lower iw ill a slate of transi- 
tion to a higher plane. 

01andul«.r epithelium (Fig. 
271 is composed of cells of illf- 
fering shapes — cuboidnl, cyl- 
indrical, conoidal, [lolyhcdnil, 
and Kpheroitlal, the last being 
rarely t'linud except in the rc- 
molcHt r<fvi<.*(w of tnbular and 
raceiuose glands. The various fonn.* of thcwr m-lls are aceonntwl for by the dif- 
fcn-nl MJiaiies of the cavities to which each ftcritw is compelled to adapt itself. 
The function of glandular cells \» wcpetiop. 

When an epithelium wniaisls of only oiio xtratitni of cells it is called simptc or 
tingte-htyered ; when Jt has tivo or more iaycrs it is known as iflratifcd. If a 
ciliated epithelium is stratified, only the ceibi of tlie upper layer are furnished 
with cilia. 



Ki'i. '17.— 'ilmnliiUri'plllii'lliiiii ■» micti In ■ mlliurf k1iiii<1 At 
tbe lowrr riKht-hand comet li ■ durt iln»l slUi ccinuldn] vnlUielUI 
ei'iliL (Ki>lllkrrO 



THE SVSTEXTACULAB TISSCES. 



45 



^^^^P THE SUSTENTACULAR TISSUES. 

^^^H TissuBt Passively SrrPoimxG Other Parts. I 

1. XoiHy fibrowi. I 

^H (a) White Fibrous Tissue (Connective Tii>«ue I'roper). I 

^1 (6) Yellow Fibrous Tissue (KWtic Tis«uc). 
^^1 (r) Areolar Tiiif^ue. 

itt) Adipose Tissue, 
r) C>eliitinou» Tiwuc. 
/) Ailenoif) Kvtietilur Tissue. 

^B Q) Xcun>glin. 

r 2. CartititgSiiouA. j 

^^m (a) True CHrliliif;^-. j 

^B (b) While Fibru-^rtili^rc. j 

^^ (e) Yellow FibrcHcartilage. I 

4. Dftttinal, ' 

The members of th!': Uirge group pre;»enl many violent contrasts in their 
phvFiiral ipmlities ; we Hud the soft uiid the liarti, the tnin»|}arent mid the o|Ki(|ue, 
tbc Hexiblc ami the rigid, the m-iirly tiijtilil and (be almoi^l stonily Kolitl, the 
fibrous and tla- gninidar, the moi»t and ihe <lry, the eohirlt-ss, tin- wliil^-, the yel- 
low, (he [n-arly, anil the pink. And yet, in ispilo of tbe-se anlijMxIul tniitit, ihc 
individiiiiU makiiifr "p 'bi.-» elasit Imve e«rlttin eonimon ■-barael«ri.->tift< whieb dis- 
tin};ui>b it from all others. One wbieh .strikes Iht- iittention inant foroiblv i^ 
the ttltMiltitr )Bi.-»ivily nf every member of it: not one of them Hoes anything 
actively ; they stand r>titt like cfoeks and stoiKw, and are aetiil upon by the other 
tiwiii'-*; ihrv orijfinate no action. But thi- si-rvii-e whieb tliev perform, th"ii;jh 
htimblc, isof es-icntinl ini|H>rl»nec-, nod in measurably pri--M^nIeil to the ininil by 
any one of the various aanuw bornt- by tlie group. " Siistentaeular " suits oiir 
|iur[>oise exeollently, riugjrci^tlng mechanieal supjiort, the upholding tltat rei]uirc8 
.-(n-ngib and endurane<>. " Conneetive sultstaiiee " U good, as r^•ferl^ng to a very 
pn^iiniiieat function — the nnitiug of ueijfhhoring parts. " Connective tiwiue," of 
l^on^se, inherently carries an equal signifieance, but the term has l>wn so mueh 
used to designate a leading member of the group, that it if nol silwaVi* certain to 
conwy one's intent to inelude all of them. "Skeletal" is highly deseriptive to 
one who has tUvested bis mind of tbc jKipular notion tliat notlnng but bony 
structures are entitled to bo conidden>d a slteletoii. Probably the best term of 
all in onr language iif "framework," beeause everybmly knoww that si framework 
may hi- niiiiie of any maierials wbieb hiive t^tiitaMe physical tpmlitiis, iiud tiuder- 
sl.ind> tlial it docs ihe work of supporling iTiecimnienllv, of (■oiii]t'<'ting m-ar and 
distant jKirU of the whole, and of kv^piiig tlicsi- .-ainic piirt.-' iiwiiv fnini ifii-li 
othi-r — the la^sl being an ofliire qiiilc as important as tin- ninri' proniinintly men- 
tioiitnl conneeiive work. As, however, the term is so little used in a titular way 
by anatomists, another ttas llC1^n .wlected to distinguish the group. 

The word " framework," like "skeletal," to an anatomist suggests far more 
than the miLs.'^ive, bony staging, which is the gross basis of the human form. To 
him it mi'jHK the delieate. and even mieroscopie, raflers, beams, and shelves, which 
serve to give definite sba]>e to minute organs ami to small parts of liirgc structures, 
and to keep their active porlioni* from pressing up<«i and being pressed u|Kin by 
each other, Si, too, in hi* miml. " winneetivc " hiis Iwth nuicroseopic and miero- 
scopic applii'atioiw. U is a name given to the tixjfue of which are made th« 
IkiihIs whieb tie the l>oi>es togciIxT, and tbi- strung, llexilik' F^inewis wliieb unite 
ei^ntniclib- oi^us to tlie jiarts which they move; siiid it i» i-quidly dcservwl by 
minute parts whieb, on a luuall scale, do work of a eomparabh- kind. i 



46 



ELEMKXTAlty TISSUES. 



Thrne tissues are very widely <ii»trilii»wl iii the body — bo oxtciisivcly, ind*. 
that their diSiit'iou may almtwit be de^^land to be universal. If even- panicte 



material extejit tlie i-ui-teiitaeiilar tlwaes were to l>e withdrawn from the body ol 
a person with whom wu wi-re well acqtminted. there would he no difficulty in 
recoguiKing him, vvvxi m mitiiitc dcluili^ of form. ^_ 

(l w intt^rc^tinjr to olx>cn'(* nol only thnt llie t^iixtentncnlur tissue?' are sitnila^^ 
in n fiiitcliun»[ way, hut that, ihcy an- ^tnK-tiindlv iillini. They originate in tlie 
same i-U-nienti' ol' the embryo, to a i^erlain exli-iit ihev aiv interchuii^feiibk-, and 
(h«y otlon ."hndi- into oaeh other. ^1 

They <?onsiwt of eells and inlereelliilar piuhstanee, though in most of ihein,^l 
when mature, the cellular element** are ineoiispieuous, and the material iHtwcen 
th« cells is so largely developed its to constitute almost tlie entire hulk of the 
tissue. 



White Pibron* Tissue. 



« 



Th(> name of this tissue is highly dcwrriplive, for it iit (ti»tinetly white when 
seen in a miLt;<, and its Jibmus ehanu-ter i.i mnaifoT'l. It ix often cnlU-d "eon- 
npotive tissue r>roi>er," or even merely " eonneetivc tissue," because of itB great 
abundance, botli absolute and comparative, and ils very wide distribniton ; hut, 
while its cotispieuousness among the sustentacular tissues entitles it to the name 
which implies the fact, the designation is confusioc:, and would better lie droppf^l 
in favor of the descriptive appellation which is acre chosen. Teased out with 
needles aiifl viewed with the micitjsccipe, it is seen to cfinsist alnitist whiillv of 
extremely tine, colorlew- fihriU, arninged side by side in bundle-^ which have an 
undulating outline (Fig. 28). The fibriU may be very long— some inches — and 
do uot braitch. Closely applied to tliu buudle» of fibrils are cell.-- ; but tlic^c are^ 

not u prominent feiiturs^| 
in the adult lii^Kiii', and 
uri- liable to escajM- alten- 
tiiinunle^i^laitiing.igents 
an.'Ui«ed. TIkmtII!- pni|RT 
to the tissue are tiaiiened, 
irregular, micleAttHl,gr:t II- 
ular, and have long pro- 
cesses (Fig. 20). 

White tihroustis-sue is 
distinguished chiefly for 
its great strength and 
flexibility, and is found 
where these qualitic;^ bv 
themselves are needed. 
For exitmple, it if alnioi^t 
the oiilv lijasue in most 
of the IwindK (lig-.iinents) 
whkli fiiisten the hone.'* t<^tlier, and in the cords (tendons) by which the forci- of 
museulnr tisitue \i transmitted to and applied at distant (Mtints. In the.->i^ situation* 
grciit strength is re<[uired, for without it the hones would readilv beeome dUlo- 
eated and the nuisenlar contractions would he fruitless of i-esiilt ; flexibitiiv is 
demanded, since rigid ligaments and tendons would either prevent movement or 
break, and thus prrtve useless. If, in addition to strength and tiexibiliiy. elas- 
ticity were added, the bones would get out of place during many movements, and 
muscular contraction, instead of moving the object ti> which the distal end of 
the tendon was attached, would be devoted in large part to the stretching of 
the tendon itself. 

Thtiw illti.'it rations will show that this ti.<4U4> \* well fitted by i(» phvitioni 
qualitiM to Ruik« up the rope.i, oonls, protective »hecta, and outer «n<^IU of 
oi;gHn«., 





Pu. 28.— Whlt« flbroiu ilvao. 



Fiu, '.■.>,—■.'« Ill of trhlM HbtDIM 
U»ur.oa«a cilicd coiiiMetln>tl» 
(Ue CKll*. 



YELLOW rrUKOlS A.\D AREOLAK TISSUES. 



47 



Yellow Fibrous Tissue. 

This tcxiun" \* M>mp(iHC<i mainly nC tltm-s, aiul in litr^ mastwa prownU a 
t]rr>cii[>> yt'Ilnw hue, fnim whHi I'aols il is Danud. I'mlcr iIjp inicrot.r(>[K' its 
filiiT^t art' sft'n to diffi'r mnterinlly fixmi those of while filiroue li*i«o : thoy are 
nbttnti-like, ihick, hranrhed, atiH cnrlr<l at ihu ends into hcKtks, vrlii<.-l) result fnitu 
their frartiire in tlie ])re]winitorv (wwing I f"ip. ;tO). The eliief phyi^iml pn'jx-nie* 
uf thi- li.-v.-«iie nn' slren^rih, flexibility, niid el]U'(i<-i(y. the lui-l beini; llmt wliieii <li»- 
lingni-ihe* it fn>in all otliere, ami ftivi-!* it llu- iimne by 
which it iy often known, "eliwlir liwne." Khwtifity, 
the ()ttality whieli re«tore5f h(i<ites pi^iiwessiiig it lo ilieir 
nonnal ^liupe iift<T dirt^irtion, is ivot to \k- o)itronnile<l 
will) (<i>ntroc(ility, the Httribnte which enables a body 
tu fltoDi-ii a iliameUT (lor example, to dmw its two 
vnA* mian-r In eaeh other) nn«!er Ihe influenee of a 
slimiiltiK. El.iHtiiilv is a merely pa^ive pronerty : it 
Ranmx dUphiy itself until some outf«ide Jorec haa 
strel<rhed or otherwi-«e defonned the substjini-e in whioli 
it resides; bnt coiitraetility is active, and is muiiifeHted 
under influences which have no ^w\\ ctl'eet iii»>n elastic 
bodies. The eliij'ticity of yellow fTlirmi* li!<-iii(*, whtlu 
dl^iuilifying it fur the wnrk of tendcin«, I'ininenily fit:* 
it for other dntiev, iukI it i* found jHrfiinnint; viiltiiilile 
wrrvioe in ntiuiv places. Wherever it U hh'jiU'd, it (loe» 

En-riM^ly iiueh work iw imtin-mbbiT wouUI do, if ginii- 
ir!y iirmn^l. II. is eoninionly associated with white 
filimtH tissm*, thon^i in relatively small quantities. Th« 
iiuouni of it in the sj-stem U not large as compared with 
' that of white fibrous llssiie. The clearest masses of it 
are the li|riinientii subflnva between the laminae of the vertebr». 
not w|ual to tliat of the white fibrous. 




PiGL 30.~Y*tlii>T fllircnu U*- 

(•^l lire 111 II. I 



Its »trcii|rth i» 



Areolar Tissue. 

Arenfa is the I..ntin word for "n little s|uiei-," and nrooliir tisi*uc frete it8 nnmc 
from its app<y>ranee of beiuj; full of minute sjiaees. It i.t somel iinc willed "eellu- 
Ihf tUsue — a term which hits no jitililii-ation to the lii.itolugist, to whmn ihe won! 
"t^ell" has come to have an arbitrary meaning, entindy indei>endent of i(» elynio!- 
jOgj". The designation "celhiliir tist^ue" is applicable properly onlv to a texture 
'tuode up subet^ntifilly of tbt: histological elemetith called cells— eucn a tisAUe, for 
instance, as epitliciititn. 

[n areolar tts!-tie we discover no mutvrinl different from those whtch we have 
alrpsiiiy stliditil — ■inly a new arrangement of some of them. It is eomnosed of a 
nitxtun- of while ami yellow libroiis tissues, sodiK(>o-ii-d in iiregnlarly erisw-er()>v>^'d 
biindlex as to make a network, the meshe.s <if wliiih biinnd innumerable ureolie 
(Fig. 31). The bulk of each bundle is while tihroiis tissue, mid around it are 
liHisely twiuMl thniids of yellow tihrous Lis.-*no. Thi^ little siuiees Ix^tween the 
me«<he!i are not delinilely walled, but are indescrilialily irregular o^vities, which 
i^tnimuniejite in the fn^est \v\\\ with eaeh other ( Fig. 32). The fuseieuli iin' nmisi- 
rntil by a lymph-like fluid, which eontrihules to their flexihilily ami dimitiinlM^ 
tlie frietion helwix'n them. 

Areolar tiivvue is found almost everywhere subjacent to the skin and nineoiM 
and serous membranes, between niiiseles, b I o(k1- vessels, nerves, and other parts. 
It forms a layer which i» attaclH'd on one side to the deeper structure, on the 
other sid<! to tlie more superficial. Wlic'ti one of these struetUR-s moves, the 
arw>bir tissue [wrmils it to slide tijion the other for a little ilislmicc, the wavy 
bundles of while tibroiw li*«ue being stniightened out, and the narrow ribbons of 
yellow fibnms iM-ing put nil the .'tireleh. The motion oeiising and the disturbing 



48 



ELEMEyTAHY TISSUES. 



apviicy Ijcing rpmovpj, tbe strainwl yellow fibres sj-^ert their elaBticity, pwll tht, 
wliitc fai^k'uli Imok into thpir iin(liilnlmii», ami «wist a littlo in tlip rcstnRition of 

_ iIk' iHirts bctvvwii which it lies to ihcir 

fonuer iittittiilc of n'[)OM'. The tbuit^fl 
■» conn('(!live in a typiuil wnse, ^^ 

Diseai^e and ucvidciit iiffoni litrik- 
i«g illustration.-, of tin- fivcdom of 
iutcrcoinmitnicalion of the aivolie, 




Fio. n.~ ArrnUr ilMue.comiioHd of bunillca of whll* nhmiu 
Ilauc and bnuichod inranili of ; vUuw ntiniui ttmiu Iixntly liih-r' 
IhIiii-iI. 




Pto. XL—a pnrliiin i<f arvnliir lluuv I 
llatwl toa iiliiA, itmwiagmitom. 



and aUti nf the vti»t cxtoiit of t1ii« «tructurc junt beneath the (tkin — here callc 
the subputaneoiii* areolar tiivne. The lymph-like fluid mentioned aliove ia' 

xonieiiini^ forniid more nipi<lly than is normal, 
or, wimt Einioiiniri to the Mmie thing in eHi-ci, it.-* 
iih^orption i* let* nipid than its formation, and ihe 
«XOi-Mt Acciiiniilatei^ tii the nreolip, But, aa eaell of 
the>e KiKui's opens into all of itf- iKij,-hI)ors, the 
fluid ;ir.iviliil<w frotn one to another into tln>H? 
whieli art- nmsl il<-]))'ndent, and the«' it dli^tendii 
pro)Hiriioiiiit<-1y to itc amount. In Mieh a nvi.; 
when the fret Imve liceii iJiitui the lloor all day, by 
evening; tliey ure s\volli-ii ; l>iil, at'lcr tlie |iiilii'i)t has 
j>asf>e<:l a ni};ht in bed in lite Ijori/nnliil position, the 
enlarirenuiit di^npjjears iihiiost iiitin-ly. lueausc 
the tinid lias ^jravilated l>afk iijiain and litis hc- 

?;|M 1'% eome widely ditVused. Sttmetinu-w, as in fnu'tunr 
^■W/ '^^ " "'*' " '*'""'l' i '"'ten lent of hone )(erforate!t tlie 
^ chect-wall and slij^ihtly jmncturea the lung, leavinji 

a an ojx'n iraet lietween some of the air-vesielen of 

M the latter organ and the areolar tisitue near the 

^ ifiirfuee of the body. Even,- time that air is drawn 

infij tiie lung, Hinie of it ecraijRf- tlinmgb the aeei- 
(h-nliil "iM-ning into the Bubeutanenop areolar tissue, 
the ^pai-ew of which lK?eome in Hated, at fir*t onlv 
in the region of the injury, lint at ea<li bn-uth 
tnore and more extensively, until finally nil of the hrvIr' uikUt llie ekin nre i^o 
ballooned that the vietim presents sneh an npp<'nmne<' jus is shown in Fig. 33. 
The areolar tLswue around eertain organs, a.- vessels, iK-eoini'n somewhat erni- 
denM-d and fonti« a divttuel vhealli. The nourishing vt^tii'l.i of a i>art are situaKtl 
in It* areolar ti!^<iie. In the tiarrow «[)iiees helweeu (he lobules of a solid oi^n, 
*» the liver ; forming a layer ontsitle of the mucous coat <if hollow organB, us the 



Fi(i- gt— Iiinmli'n of •iiWiiiHTii'iiiH 
nrrrfliir TiKMfr* 'In*' i/> ItilrodrirO"!! '>r 
itiT llToiisEh n M'Ltuhd In tht ch«hi'H'al] 
anillutur- iticou-i 



ADIPOSE TISSUE. 



49 



tduDiacb ; eveiywhere amotiff bundle* of fibres, ai^ in miist'le, — in all eudi situa- 
tioDA ia areolar (issue, funuHiiug a j^jtriuKj- huA for (he t)Iuo(I-VL-e«cl«. Indeed, it 
may Ite laid don-u iUi a rulo tliut viwh.-I?' urv d(-vvlt>|)(tl iu tliis sort of tissue, aod 
alwaj'6 contiuup lo owupy it. 

Adipose Tissue. 
Arvolar ii;^uc has been dp-wcribcd aj- «)ni|iosed of while and yellow fibr 
8u«s, dL'iMKk'd in luch a way a- to leave irregular i^piices between their bundl«0 
Somif of tn« oclU of the wbite tibruuH tie«ue of this eombiitution tn eertaio cir- 
oum.'itanct^ undergo jteculiar ebaup->^. Tlu^ outer biycr tuink-iiH, f^>rnii»]; a deli- 
cate cell-wall ; ibe im»Hl of the miWiiiiiw; of ihi- trell is coHvert^Hl into liquid oil ; 
and the iiueleu^, |irovioiisly eentnil, is I'mwdtHl iilf lo one j<i<le, thu.* becumiugj 
[ieri|»beral. and i.- tV-<leiH>d to tbe in-ll-wall. TIhh i.* furiiieil .-t Jul-cfH (Fig. 34) — j 
a veritable sae of liquid oil, lie.'iii-rvioji: tbe name 
"eell " in tlie ctymoU^ical mt well w in tbe his- 
tological «ene«. Sueh eelU are linlged in tbe 





Fmi, tk— Fatreni. n, nUtd kIHi oil; b, clli«1ul«4 of 
oU. Uio atl-vsU tbriidllod. tK<»llkGr.i 



Fn> S.— t'si-i'i'IlK i<arl:<i1 rliMvly tosctbct, 
And Hum bmituliig ]Kjl}iiiHlrmI. 



spaces of areolar li8»tH> very (jeucnilly ; but in a few loesliljut they are irever 
seen — the pcni.*, tlio eyeli<l», the eJivitv of tlie er.inioni, and tbe Itin^ (exwhting 
a little near the root^]. Wben tlie inunber of Jiit-celU ia sutiieieut lo lit) tbe 
areolie even nimbirateiy, tbe liianu' is ealle<i fi-ii/^'tw or /attj/. The cell* are round 
or ovoid, except when tbey are closely luu^ked.aml then tbe mutual prt-^un' jiri,!- 
ducf^H angular faeeta all over tboni (hig. -I.'i). Fatty lisnue is yellow, wifl, and 
resilient when living, but hard when dead. It'' snionnt is ver\' variable, and 
there is no al*solute eriteriun of the normal quantity. But wlivn its i^iifting line 
of h««ltbfnl development U ovcr«tep|M.'d. olx'sity or corpulence is reached — a patbo- 
logicsil condition whieb may inlerfi-ri' with I he proper performance of vital functions. 
Sometimes tbe fiit in ibe alxloniiiul wall atliiins a thickness of six inebeR. 

The usw of adipose ti*^ue are various. It is a enshioti fur oi^iii^* — the kid- 
neys alwiivs lie in a bi-il of fal, and olhc^r cirj^uis are similarlv prnvidf.il, tbon^h 
le*! Iavi:'bly. Hein;; a slow tn»n.*niittcr of heat, it is a proti-i'liiui against eolil — 
it i.H always found iu the great scrou." apnin wbieb banp> dnwii in front of the 
boweb, and doubtless serve.-* to keep them warm. Adipow tisi^ue is a reser\'oir 
of natrient material which in drawn upon in starvation. If an animal in d<^)rived 
of suitable food, his sj-stcm relies hirgelv upon its store of fel in the emergeney. 
If a wolf and a «hccp are starving, each feeds upon its own fat, tbe herbivorous 
animal Iwcomin); for the time ])nictindly a carnivorous one, since it lives on 
fat mutton. A man wastins; with fever lives on his own tissues — amnibalistically 
conHmic-s bnmun Hcjsb. The adi(Mts<', Winif a cheap tissue, is useil most freely ; 
ncrvoiis tis.vuc, the most eostly, sntfcrs the h-a-*! low of weipbt. During the 
pnK-rws of star\-niicm ibe oil is abstnictiHl frmn ibc eells, nml the walls bci.!ome 
M'finkled and eolhijised. Tbe nuclen.'<, b<iwever, ke<-[)S alive ; and, \vb<-n nourish- 
ment U airntn ap|inipriated bv the .system, the nucleus heeom<-s aelive, lakes fn)ni 
ihi^ blooil the materials suitimle for the manufaetuiv of oil, combines tbeni pn>[>- 
crly, aud depanils tlie product in the cell-eavity. which soon becomes plump again. 
Kinallv, it is not unworthy to mentiim tbe asstbetic effect of a reasonable amount 
of adi|Kise, which soAens tbe asperities of sharp angles, and contributes to the pro- 
duction of the gmccful contour!), which are so essential to perfect Ixtiuty of form. 
4 ■:•'..'■■■ 



so 



ELEMEXTAJiY TISSUES. 



Gelatinous Tissue. 

Tliis tissue is jelly-likt", as its name implios. It is niso <!a]le(l mnemix timue 
and mutrritl fitxiif. Sn tvpical example tit" it occurs in the adult b<Mly ; but th« 
gi'laliu of Wharton in the umbiUt.'ul eord ilUif^lmtos it [terfectly. Here is seen 
a protopla.-niie network, formed bv tlif union of the proeej-ces of cells, which an! 
identical with tliow of white fibronw titi^nc. In the mcBbcs of tliis reticulum 
is a f-cniiHtiid ground suImIbucv. Thi« ti^isuo is the mo^ immature form of 
fibruus tiiwuc. 

The vitrcoiw boily (or Ininior) of tlie oyo is c()uijwf»ctl of gchilinous tiN^uc ; but ' 
the fibrou.-s cU-iiicnt in ^o slighlly<it'VcIopcd ihiil its cxisleiKH^ if- by (-onn- obwrvcrs 
dcniod, lUid iilinusf all of ihe oclU have ili.siiijxm-cil, the few which remain bi-iii); 
sliriiiikcn and iiidistinot. The vitreous is in liirjrc piirl iiiboui 9JI per ci-in.) water, 
and It.i iippi-aran<'o in that nf a mass of btii mi fully U'aiis|Ktrenl, cokirU'its, inid 
delif!iti> jelly. 

The service [teribriucd bv the vitreous is strictly snstcntnnilar. It is the 
ntufliug which keeps the ball of the eye in itfl globular sha)ie, preventing the 
wrinkHng of tlic retina, which would he utterly destnictive of detinitencas of 
pighl. When lost, the vitreous is uol restored, luiving a low vitality and prao- 
tically 110 recuperative power. 

Adenoid Reticular Tissue. 

The word rHiciilum is the diniiuutivt- of the Latin rcff, "a not," nnd conse- 
quently means "a Httlo net." "Adenoid" comes from the Greek word for 
"gland," and signilics "gland-likc." Ailcuoirl rrlinihr 
ftwic, llnrtfori', iiK-an* the tisMie fi)rniing ihc nttwork in 
gland'liki' KtriictinT.'', parlicMJiir reference being hiid to lh« 
fntnii'Wiirk of tht- Mi-ciilled Ivmplmtie glands, which are 
far lietler nanuHl " nodes," nince they are not real glands. 

Tliii< network has jiiiinl^ of ros^ciu bianco to areolar tii»- 
BU(- — may, IndeiHl, he rrgnnhti ai» u nxidifreiitlou of it. 
The retieuhnn con^Kts of Mrands of while fdirou.'< li.-.-nc, 
with few, if anv, yellow fil>iv:> interniingh'd, and these 
delicate traheeulie ("little heanis"), which support the 
proper suhslamv of the niKle, are nearly or quite coverc:d 
bv fihmus- tissue cells in the shape of broad, thin plateB 
closelv apnlied and wrap|K'(l around them (Fig. -'Hi). 

Tuougii the mont charaeteristic display of thii- tissue ts 
the lympliatir uode», it is widely distributed in the body, and is particularly 




I 
I 



ni. !*— Att«niiM rvtlc- 
ulat Uuuc. 



in 



abundant in mncnuH membranes. 

Neuroglia, 

Literally, the word neurogUa mean.s " n<'rvc-gluc," and is misleading, for it 
is u«,-il a^ the name of a network supporting ihe nerve-substance of the brain 





Flo. n.— Scnroclla «IH. 




spinal cord. This reticulum is not made of white fibrous tissue, &n i» that 

•. ••••: .*. •'i:"' • " ' - 



CARTILAGIXOUS TISSUES. 



51 



I 



of ndonoid li.*.Mn>, but Li comji<:)p^(l of jioptiliar liodio.*, onllofl elia-^i'llt*. ami tlM'ir 
7<*i-^. T!u- oelU (Fig. 'M) are irn-gular iind sti-liaU-, niul lln-ir branclit-.s iire 
"rayi-tl out at tlir cnil in tufts of minute fibrilH, nliich rankiiy everywhere Itetwwn 
tlio iHTveM-elln ancl libres, 

HesicW tlip ncurt^lia, there are twfo other means of nieehanieal suiiport. for 
the tissues of the great nt-rvous oentrn;. From the attaehetl )M>rti<>n nl ibe epi- 
tbelixl cells which line the cavities of tlie bruin and spinal eon) dclieatc libnU 
nm p<.-ri|)lienilly aiul cn<l in the- [liu, (lir HbroiiH and viL^ttlur covering uf thoNO 
masses. Finally, ttit- jiin it«i-lf n-ixU |tr<>liiii|^tiuns inward, which an? uf uiunif(T«t 
suetcntacular value. 

Cartilaginous Tissnes. 

Cartilage, popularly called "kHsiIi'," is u deniw tu&uc, but mucli [v** bard 

than bonp, elastic, ami ^r^'ing iniportaiit iskvktal aten. 

It oocnrt" in three Viirii-tit-s : 

Tnie or Hyaline Ciirtilttgt'. 

Whiti- Fibni-ojirlilas?.'. 

Yrlliiw KtIii>t-(^rtiliifro. 

Hjaline cartlUgfi \» ^i> tunned from the Greek word for " glas!)," because of 

the lnin»|iart'itiy of n thin (^licM- of it. It i» aUn ealled truf fnrtilnge, )>er:au.Ke it 

» l\w only varii'ly wliiclt pi-esonls pure and unmixed tlie ft-aiures whieh chnrao 

teri/j- thi^ tiiwue. Ii encrusin (ho jmrl.* of Itorn'^ whii'h enter into the eompo.'iiiioa 

of movable jointx, in siioh ><i(iiati<'ns, hi-infj cjitted artienlar eartilage ; it forms 

the exten^ions of the ribs to or (ownnl ibe bn^ast-bone ; it coiisliiutes the bulk 

of the larynx ; k atiffens tlH? windpii«' and bronehial tubes wiib t.irips and 

platefl ; it is the framework of the fnmt of the nose, and does simibir service in 

one or two other places. Hyaline cartilage is opaque, bluisb-whitc, firm, chw- 

tic, and rradily and smoothly cut 

with a knife. Covering it closely is 

S coat, called pfnehoHilrium ("around 

the oartiliiRe"), wliieh Ii;l« an outer 

fibrous and an inner cellular layer, 

and ii! the agent by which the pro- 
tection aiwl gniwlli uf the wirtiiagc 

an- cilwtixl. Liiiilcr the iiitcrnwoiK^ 

Kirtilap- ii" j^ecn to consist uf xinall 

riiiHti'm of riiinKti>li, niicb-iifi'>l (i-IU 

< Fig. .1**), <'«eh group crowilcil iiiio a 

litth- navitv {lacitnu, "a little lake "), between whieh and its neighbors i^ an 

expanse of apjiarentiv homogeiU'OiH intercfllular Mitirstanc« (matrix). The ivlls 

am motliflo)) Rbmus-ti^iue eells (the wi-cniled 

eimn(>ciive-ti«^iie cells), and the matrix is 

n^lly oompoised of extn-nn-Iy dilieate fibril- 
lie, the nia** of which is pervaibil by mitiiile 

lymph-channel 1-. C'srtil.-ige is no n -vascular, 

and tlic nfmrishitig material for the parts tar- 

tlic!>t fniin the ^urfiico permeates the llsstic 

thnjugli lli'^t lyntpb-|Kiths, 

White fibro-cartUagi; U utberwiMC known 

a< fi/imnjt mriilwp' !iri<I tihm-i-nrtU'U/f. It 

mnki-s the gnut di-^ks between the bixlicn 

of llu' vertcbne, the plat<« at the movable 

KvmphvM-*, the iniii«<i'« ix'lwi-en the bimcj* in 

llie frr-eiy-niovable juini*, nnd the nodules Fw. sa-whit* flbt»<«mi««. 

which strengihitn tendons in exfxiMil sitiia- 

tiotk-t. It has no prupcr iM^richondriiiin, and, indeed, is more like tcmhin than it 

is like triie cartilage. .Miennscopieally (Fig. :)t)), it is seen to consist of a dcn» 






lir cttls. iTntuI I 




62 



ELEMESTARY TISSUES. 



ft'ltiii)! ijf wliili- fibrou* ti»-iiu', imiKii<Ii'(] in which arc nosU of rariilagp-ctlb, as 
il'llif w-i'ils -iri-arlibui- iiikI t!i'i.-c nf ciiiiin'i-iivc Iishik- prop-r wert suwn lognrthcr 
in tlie wiiiif^ fi>-l<l ami ilfvtliiiii'ii in an iiiiimalc mixturr. The phv'iifal pnipiT- 
ties of the tissue arc such as would be espeoted from such an as^ociiitiuD of iiigre-j 
tiiciit'' — clar-ticity from one cIcrnLiit, Hcxihiliiv and toughness fmni the other. 

Yellow fibro-c&rtilace i^ I'-illi'd i\\M^ ilnKlir ntrtiliiyr and trlifiiliir (" \wtwtiT)(."\ 
nirtUtiiji; for T-triictiiiii! rfa^tms whiili wilt pn>si'ritly In- manifi'^il. It^ priiic'i]iul 
(■xani|il(-s aiv ihc fi-.imowurk "t" the auricle and that i>f the epi^Iotiin in the hirvnx. ' 
It i-- opaipio and vt-llnwijih, and more eliistic. {icxihlc, and tmijrh than hyaline 
ortilinfo. Viewed with the iiueroscope. it is seen to con-->ist of a ilose aetivork 
of yellow fihroHB tissue, containing s«?att€'red (rroups of true cartilage-cells (Fig. 
40) — a composition which readily explains its physical cfualilics 

As Ixith the -iccond and third varieties of cartilage 
have a fibrous tissue mingled with tlio true cnrtihigc, 





IflQ. 40.-VC11OW fibroninlliUP!. (KOlllkirr.l 

the names " fihn)-«irtiliigc " and "fihrotis cartilag*" 
do not differentiate one from the otlier. As all carti- 
lijge in elastic, the name "elastic csirtilage " is not 
clearly helpful in the designation of thut conliiininti 
yellow (ilirous tissue; and " reticular" \ji no better as 
a title for the third variety tlmii \i^ "fibrous" tor the 
Bccond, since in each its fihrou;^ lisnwe i.t urnitigi-d as a 
network. The names wtiivli ure given nl>o\'c arc pri^- 
ferred because they actually convoy a oorreol idt-Ji of 
the structure of eaeli form n-sjM>c lively. 

Oaseoiu Tissue. 

The word " osseous " is derived frttm ihc Ijikliii o«, 
meaning "a lionc." Okn»'ouk ti!«siie, lIuTcfon-, is bony 
tiiQ'UC, and it U the ohanict eristic msitcHiil in the iMinc.-. 
A bone ill one of the numcroui* hiird oi^inM, which, 
taken tiigcthcr, make up the nkeh-ton. One of the 
long hones of the limbs will show typieallv all of 
the fciituros which we need for the .study of' osseous 
histoloiiry. 

A long bone has a central cylindrical portifm, tlie shaft, and an expHndei) 
portion at each end. The parts of ihe cstremiiies of the bone which present 
eurfaees in movable joints are crusted over with a layer of cartilage, and the rest 
of the bone Ls covered with a fibnuis and vascular membrane, called the prrh»- 
tiitvi, meaning the structure "arounil the hone." The fibrous part of the perios- 
teum makes it protective ; the vn Mm In r' serves for the nourishment of the Iwine. 
The di'e|»e»t portion of tlie periosteum is com])n»ed of cells, <':tlU>d '»tli-i)i/nir/lo 
(" lMUie-l>egetting "}, because essential to the formation of os.seous tissue. I f the 
bono ia divided into halves by a verlicjil cut, its shaft is found to be hollow 
(Fig. 41). The open epucc is called the nwrrow-ftwUtf, and is lined by a fine, 



^^i^ 



<tf| 



B^ 



Fia. » —VtnlfAl MClloD or I 
loiiB biiii«, iTivtuU 



OSSEOVS TISSUE. 



53 



fibroiw layer, the mftn/ieum, mt^aDin^ the slmclure "within the I)on<'." Tlie 
Duitvrial ill Ihi- oiiti-r |Kir(? i>f llw Ixmii- if vt-n' dcnspj antl w, tiMiw-tjiieiUly, 
known lu" (ywn/wcV luvtrniK litum: It is; vi-ry tliick in the ^hat^, bnt ^ihadei) 
>irt' towani ihv vx]iiin<lrtl cxtH'mitics, nnil in thrin w nwtrly ii thin shell. The 
n<M(hu' t>r the Imni- hn-t the a)i|)('iiri)npt^ of a n«-Mvork, with Ihi- (incft iiui^hM 
Dfuni-t the iiutcr !<urfa<«, the ctnii'scM ncxi to the ninrrow-i-avlly. It i« called 
"fionify iiMftiHK iisKui; on acnmiiii nf its |K>r(>iis charartcr, nnd iiiinv/fou*, (n^ni 
ifc- heinjj a latiircworb. But c«ni|iael and spongj' are tcmw whifli hii\e rcf- 
tippiK-e only to gMfs ap}>eaniiicP!i, which are eailflefl by ihc arranp'nteiii i)f 
the malarial ; the i-lnictiire is essentially the «inu' evcrvwhere. The morrtitr' 
raeiltf is oeeupiwi by thv uutrmr or uuiiulln. a very vaTiiIar inateriiil, eoiitiiin- 
ing many peculiar IxxHcs {iimrraw-r*iU), which iire larpely elianped into oil as 
a(iiilt life is nppruiKrlK'd, the rulor of tlit- niurruw bviiig, tbercJore, altered from 
iwl to yellow. 

Osseous tir^tie is itni- of the Imnti^l ni.-ilerials in llic bmly, W-iii^ ?'iir|Ki^eil in 
doiiMty hy two tisfin*-,s only — ik-n[ine niul vminiel — hixli of whii^li i-xi'.t in the 
t<i-lh. It is vi-r\' |oi]t;)i ;iiiil i-liistic, it* woll as hmv), and will n-7iii<t j^iuit siniii 
vritliont brenkiiig. It is (■iitii|KMi'd of two kinds of snlMtaniv, 
vartliy and uninml, >o inlinintely <-on)niiiit;liil iliiit, if t-ither ii* 
removcil, the other nuiininin^i thi^ form of bone even in iL-« minute 
detiiiU. TIh* eanliy matter, whieh i* nnnstly saltn of lime ;)nd 
mak(s up Iwn-lliirdH of the weight of the bone, can be rcinov»-d 
by the action of a dilute acid. The lione i.-^ Ihu.-* di-ealeifnil, and 
conjoints of a bmwniwh, toiijrh, flpxible, and ehtsiie malerinl, so free 
from stifTiiess that the bone, if a very long one, may l>e tied into 
a knot (Fig. 42). The animal matter can I>e driven 08' bv heat,' 
When this has betii dune, the bone Li white, rij^id, niul brittle to 
the Inat decree : it van W eni^bed into fntgnients between the 
thumb and finger. In (lie fre-h condition the color of bone 
is delicate pink In the comp!u-t |H>rtion, deep I'ed in the ameel- 
latcxl. 

[f tin? idiuA of :i \i>n^ lK)n<- !i« Kiwed in two trauHverscly, and a 
%'cry tliin slin- U n-inovcd from tlii> cut furfaee mid examined with 
the micniwope, it will Ijc neeu tbitt there are numerous) nearly cir- 
eiilar or ovnl |H-rfio7ilions, .iiimui) eiu-b of which w n htics of con- 
Ofiiiric'rintrs, which represi'iil loni;, b<il!oWcvlindei's Htti'd aeenriilclv 
otic oviT anolbiT, wi as 10 form :i soHil rml ]h -rfonited from oml to hmVc" «iih')! '"'"• 
viul (Fij:. i;!). This i^mstit iilcs a Hdn-roinn Ki/'trm, niiiiicd frorii i'lr'l.s'ri',!' In. • 

t}w celebmttKl anatonii.-^t, Haveis. The d eulrie rinjrs are /(/- JulJiJi^:')"' ' ""' 

taellte or Itimime ("layers"), nn<l the hole in their midst w ft 
Haversian caiLil. In the solid sulistanee of the hkI ai-e numcrimt* smnll exm- 
vations eallct] Ufann (" little lakes "l, from whieh radiate in ex'ery diivetion fine 
eluinneU. called etuiiiUrnli (" little eanal.H "), which, liv uniting with those from 
liei(;lil>oring lueiinn?, csliihlish a free eomniiinicalioii hclwceii the Haversian cana! 
and the Invuna' fai'thcjit iiwiiy from it. The lacunje and ciinalicitli arc lymph- 
paths, and are important agents in the nutrition of the Wne. Tlw Haversian 
niruil i.s occupied by bliHKl- vessels, nerves, and lymphittic vcswK-Kall imlMildcd lu 
n miLss of nn-olar tissne. The ciinals have a jji-nend Ion)!ilndin.-d din-ilion, but 
iHttiie run nmn' obIii|uelv and conncet the more vi-rtieiil. Inimediateiy siibj.-iecnt 
tit (be |HTi<K>lenni niul |Kii':dtrl to it is a series of hunellie wliich form a eoniinnon.s 
i<b<-iitb for ibe niort- eentrid piirls, iiiid :tre eiilb-d i-irriiinf'-ri'iili'il lirutMr. A similar 
arniiip-mi-nl obtains at thi- inner fnv surface, si-veral eoncenlrio lamellie eneircling 
th4> mealnllary cavity, an<l standiii); in tin- relnlioii lo it tluti the Haversian laniellw 
do to ihfiir ceulral canal. Indeed, this inner eircnmfcreiitial series with its con- 
tained marrow lui" l>een called a mammoth llavei^ian system. In the s)Hices 
iH^lween the Haversian systems an? series i>f layci-s arranfjed at irregular iinglot 
lo «uch other. They are called intrrmfiVuife lamrl/tv, and, like ihv inner and outer 




64 



JELEHEXrARY TI&WES. 



ciiviimf'crciitial, uro of iM-riuRkiil rornisitiDii, the ix'iniiantir of an earlier stage of 
growth tli:iij ii" shown in iinv Hiivci-siiiii syslvm. 

Tin." Iiicunu' iiix- oiviijiii'ii h\ luu'li'iili'd i'i)r[iii«'li.'.«, ciilli-d hnvr-frtl*, fiiio pro- 
ctiwi.'" I'f wliicli fxlt-iiil into till' I'aiiiilii'iili. Lucuiki- mul ciiimliciili itr<' churuftcr- 
ii«tic of ortsi'ourt li«"ni-,nml arc foiitul in all xruf iMint-. Hut Hiiversian i-iiimU iimnit 

Eii!st!nt in jilatps of l>one wliich arc- so iliiii that sufliciciit iii>nrisliiucnt i,% iiffoi-ilcd 
y l>loo<l-VD[»iels iijion their opi^sitc Hurfacoi^, at* in manv lanielUe of the caiicelloim 
ti^iie, and frequeully in ii part of the Ineliryniol lione, 










L 



Ftn, 4!.— Diairnun at Uid ■Iniriuru ol laainnn iiB-\if. A 9»ia11 (Mrl n[ ■ (miitionc •i^i-tlnn of the ihift uf ■ 
rboTiir U vtittwn- At llio iim>vriiK««i pun Ln O^n ruiriianU'inii i-iit*:*!!!*: ^'^*' oiithliU' "t (Tit ^Hnir: ui Ihi 1i>^«*rv 

Ipatl I* Ihp FnittwtFiim lliilntt '\\p iiinrmw rsiity. KvIHih'H tIii->o it. \he ('i>iiit»t't Ouuc, pomlnlioit Innii'l)' 

ora*cr1o« of iruvr-mlAn tiv:<Tm», t^aoh U'lua vlrvi^iur In *>i]tt^Mi- ninl }>4:rrurul(<cl by fictnlral I'jiria] In th« T\Tvi 
mil) i> nii-i*" ■■Jiilj liii- ar-'ii i«*iiiil.-il liy ii lyitim; In 111.* nvipii.l ii •.■.•II 111!' ct.iiffiiifli- miniiu.-nu'iit nf Ihe 
Iriiiivllii': III1.1 In "!>*■ >>\hvr* rr>}KH'U\.UT E-iuuLltrtrlt ; liiniriif- Iiii-uiih hh.I .-fiTinIli'iili: llu* c'i»iiE.'rEl> .iflTiu i'Ui.aI. 
■rtcry. X'riri, jymphiitlc. nnirl urool'ir U^ti.^ : LnrTivllit, 1ai'iiT>ir, tii't c^iTinUrrj]] . nrTi). rlrinlfy, hII of ilii' ■iriii-ttir'* 
er^uilhdlriEn ^'omi.li'tc lyitcm. Ik-t'A'^'n On- >mi?rn!i atv i:lroupif<.'r.'iHliil (iii'1 Intcmioillril.^ lni&flt"'..N»W n fo» 
of vli[i-1i d.TL- ti^|iri*onToil hh UMluitib' Int-iintf , ihitti^Ii Ii ii i" U' LitirAvF^TnuHl tliiLi InrtiTiii- firr fri «IE iMiTit. ITio 
IwHiJHti^uiia IjlMiri] (it Ihj in»il'' ny-^t a illiniuH lujvr uiul b vji«i-tiIiLr Injtr. null In Imx ii|Hiii ID. iitlaohi'd turftUA 
• •Intlum of will, from (be Dtiroui Ujvr prulwt tnuanl Ihr rlvrl-lfkc fliifn of l^li*r|ii7- (K. U. (t.) 

If II lliiii layer !« |kxIi'iI oil" of lh<- Knrfm-c "f a lii-i'iihifii-il Vnn', minute 
proj<.-cl ioiin fnim itit undur ^urfaci- niuy hi- »wu. Thi-><- nrc in\^iir<l ]irolongniiona 
of the |KTio»l)'nni, «n<I wv known ah iht* porforatinp jfirrai of Shnrjinj. They 
nrt> not fmintl in liiivci-^inn fl\-ateins, but only in the riroiimferential and interme- 
dialt- lamclhi-, which, a.- ha,;' lieen already snid, are develo|«'i;l from the ]>erio'iteiim. 
They seem to contribute lo the fitreii|rt1i of the ijortions of bone in which they 



OSSEOCS TISSUE. 



65 



exist by rivplinjr tlicm t<)}i<.-tlnT ; iiiwl ihov <;«>rtaiiilv mak« tlw attnohmcnt of llie 
periosteum fimKT U_v piviiijr it ii tiion* ihun ^iijH^rfirial htiW. Tendons, when 
aitaclutl to Ixnw, iitt- iiMl'ingixl into it as pprforntiiii: fibres. 

A delicate, lungiluOiuiil nlivor of lione is seen li> have lutDUte openingi^, which 




fja, tl —J. tniuTviw Kvllon of a \ant bmir, tiMiinit iIk; B. the ilark ptrt of J. mafolHsd VdUmetoB. 
IlirpisIiiD •TMemi nf (tlOCrcnl ilIc* arc metn. wlili iniiiili. lumcllic, ntii] incuos. Tlic cDlancencnt li iiulxilll- 
dcul I'J UiuW cflBtlleuIL AlMi d porllaaofthv citiii'r.'Uuto(1 lluuc. (Fiiulec,) 

reprewDt the trarks ofcatmliriili : nnd. if tho fliikc ia siijwrfioial in oripiu, lai^r 
bnes abo apjimr vrhcn-in liaw bin rlii- iw-rfcu-aliiic fibn-.x. Ili'Iwrt-ii (hi- apcrtiirca 
ie a vcrj- fine reticulum of fihrilhi', showing tlii" easeutially tibroiia ('hanK-ttT of 
till' li^^uc and ita ci>ii.*0(|iient lioiiiology with 
onlinary t-onnective tWiie. 

Marrow filU the cavity of the shaft of tlie 
bone and oxh>ndB into the inters))aces of the 
eanccHoUtf portion. Its «1enient!i are <4tipiM)rted 
■on «n »reo]i!ir ni'twi>rk, and it le extremely vas- 
cular, •■!«|>i-<MaUy in thi.- fijunidy bime, where, on 
aci^iiitit of ihf gn-ttl niimliiT and liize of the 
vesrM'K il^ Milor h n-d. In the ^hnft of an 
adult bone tin- initrrow has been mostly c-lian;;ed 
into adipose ii-tsue,and i* yellow. In the mar- 
row are multitudes of ifW-', like those of tibmu>f 
tUsiie. an<i they are oallt-il ninrrtnr-rr/h, TIktc 
are ai«> great, irregular ihhsm'-s nilli nuiny nu- 
clei — f/ianl-effts. The marrow and ilic nuii.-iils 
of tbe Haversian eanaU are pnii'liially Idi-iiti- 
cal : indeed, they are eouiinuoUH one with the 
othiT, and the com|Kin^on of the marrow and 
it" otK-!relin)Z lamellie with the Ilaverhian eanal 
and itr' surroundiu;; lamellip if not fancifni. 

From what ha* been «iid, it will be under- 
stood that iKs'^eodH tiiwtie eon»i?(j< of eelk, fibres, and an interi^titiul i-tibi^tanco, 
which u Miturated with lime sultit ; And, coni^etjucntly, that the feature in whieh 




uHeou* ll»uv, crfiillr nuiKnltlvd. fht titi- 
\cnU.D cdnikli uTv col Icnffihwiic, The don 
hi Ihit caiulu are (be upcaliu* uf caiiallculL 

iTiiAiil.) 



66 



EL£.VEXTAR1' TISSVJi:S. 



it principally Hiffers fifini white fihroii!* tissue ift ita iiiigiregnation with thi.* 
parthy inattpr. 

It in iiiiportniit to rpmcmlKT that the iniogrity of tho |iprio§teiim is («»ontial 
to the proptr iHmrishnicnt nf Ivjtii', jiml, if it l>ofi>nifB }jfelf(l off by afcidoii or 
by liiwiitic', il sliimid bt iipliKt'd f^pttilily in onicr to provcnt death of tlie part 
wbidi it siipplii-.'< witli bli.HMl. 



Dentinal Tissae. 

Dentinal tissue geti^ its name from tlie fact that it ninltoA up the bulk and 
«leterrain(« the form of tlie teeth, the Latin for " tooth " being (len». A lnoth 
has a crown, the [wrt which projeets Imm the gum ; a fang or root, ilie part 

buried in the jaw ; and a neek, tlie nnrrnw 
and mmieliincjii combine tt-d |»an fnibnittd by 
the edjre of the gum. If a vcrlieal sct-liuii 
is iniide ihniiigh the middle of » tooth ( Kiif. 
46) whieh hiii^ a tingle nmt, lliero i« brought 
to view II king fontnd cuvily, eiin1;dniiig the 

CROWN* 





Fie.**.— Tooih IiivviUul •cotton. Fi". IT.— IJcnntiBl luliulri. In loDRlnidlniil •wllon. 

The luwrr ii^n of iiiv cut ihuwi ihc ponfon at ilcniliia 
ui-ar Ui« |>ulj>-ca>l[]r. (KMllkvM 

pidp, the bitter lieing eomjxiscKl of veswln and nerves, Mtpjxirtcil on a rtaginp of 
areolar tiK*ne, and also a great nnnilH'r of eell-i of the iHiiiiieelive-tiwue elaw 
arranged at the i>eriphery of the cavity. Anmnd thiw ptilp-ciivity is the hard 
]>ortion of the tof>th, in which ujv ihri'e different li&- 
i-ues: a crust i>f epithelial iis*iie nil over the erwwn, the 
eniimt'l ; ii «ni»t of om-veoiiH ti^jftle all over the liing, the 
eetnentiini ; an<] the main niiiw of the .'^Inietiire, iho 
dentine or ivtirv. 

Tlie 'li-tilhu- is w hite, very denize, ekiwly allied (o hone, 
than whii-h it is a liltle harder. It i.i develoficd from 
cla-i-lv-juieki-d white tibrous li-wup, whieh becomei' infil- 
ti-Jited with linic-ijdfs. Thi* eompaet mii,-u» is riddled 
with minule ehnnnelx, <lenl>f<i! tubuIcK (Fig. 47), whieh 
radiate in wavy line?" fnim the pulp-cavity in everv direc- 
tion, except at ihc lip of the fang, where there is an opening through which paw 



"^M 




Pin. «N.— nciiiiiiiil iiibulM 
In »rD»«-»prtl iin,«li.'»1»ittln;lr 

MVltlCV wKlll, lintl lllv llIM^' 

tuliulai »ubttiiii«. 



THE UQVID Tissues. 



57 



llip viTwcL* uimI »i?rv»«>. The tubules branch as they paas toward the snrfaoe of 
ilu' toitifi. ami tlH-'iiuiirix ih |i:inR'iiliirly iKdm- jti»t itroiind them, Ihiis forming a 
Uiirk wull (orfa>-h(Fi)i. 4S), The (itrijibfRil |iiiIi»kh'I1c, ralhi! '••htnliMii4i'i" iwA\i- 
gernu-"), bpiiJ dilii-atc pmcc^-^cs iiiln the ttilnikfi. Tin- iirHbitiiiiociv of \\iv ink-ro- 
Mnpur mbulcfi pnxliicv mi u)>[K-»ruiici' of i^triiition which is visible to tin- iiukul vye. 



THE UQUID TISSUES. 

TrSSfEW I'KllFfHtMIMt A Xl'TKITIVK FrXtTlOS. 

An elaborate pres^'iilMliiiH of thr- lii|uit] tk'iiK?' !.-« not ncodwl in an i'lemetiiurv 
work on utuilnniy, liir n kiiowltilj^ of tiient, e<««[tt in n :«n|)i:'rfii'iitl Wiiy, in not 
reqiiirfci for the eiHnprehennion of the descriiilion of miiciu-copie .Htrucmrert. 
Con^H^^ltii-nrly, they «re irealpil here in n eiipsory maninT, and the student is 
rcfi'mnl lo lii* text-book on phyelology for more dotailfd aicoiints of them. 

Thf lii|tiiil lis-^ues arc — 
The Lvmph. 
The IU.hkI. 

Thev originKte in eonm-ctive tii^isue, but are w) different from il in ai)[M-»mtK<e, 
j>hyr<icai pn>pertieis a>i J fuuctioii as to merit consideration iu a group liy tdemiwlvcs. 

The Lymph. 

Fine and closelv stowed as are the elements of tlie tissues, there are between 
them spaces, mere ehiuks and emnnies, e.\tremcly diminutive and indescribably 
irregnlar, into wliieh ooite fmm the blood of neiglibonng vessels nutrient mate- 
riala, an<l from flie tiissnes theniseh'cs the substances which result from their 
n-a^te, Thu«. the tissues are con^Iaiitly fMuhed iu a mixture of their fmtil and 
excrement. The siMicc" coulaiuing llij- fliiiil eomiiHniie:ite freely wilb eaeh other, 
and open into the beginiiinfrti of minute ami delicate tntM?s, which \ast, uniting 
with others of similar >!«■. form larj^-r tultes : these pursue a like course, and so 
on until tubes of eom^idenible eapiu-ity are reiu'hed. The little crevices and the 
tulws an- resiK'ctivt'Iy /i/nifth-Kjnirrji mul hitnuli-vcwrfi', ami their content* are called 
lifjnnh. The w<inl " tymph " i-lyiiiiiliif;ii-dly mean'? "water," but hi-tolofricaily 
atm |ibv«i<>1og^ii-;dlv it is niucb mon- tliiin llii". It varic in comjiosiliou in dif- 
ferent |inrt», betuji |more.-t at itie periphery nnil rielicst near the ceiitn.'. KMim- 
inei! microscopiealty, it is .seen to coni"i»t of a elear, Hiiid porliun, /iijimr fiimjiha 
("the li(|uid of the hTiiph"), and a eellnlnr ixirlinri, the luller tloiitiiic in the 
former, so that tlib is a tissue whose inlereellular •'iih^iniee is liipild. The eelU 
are /jfut^-eorpwWi-Jt, and are spheroidal, granular, jilly-liUe, I'Llorle.-.- IxhUc^, aver- 
a^ng jvjfff iiK-h iu diameter eaeii, with a va^ruely ilefined nucleus, ami ejipabte of 
»m<eboi<i movements. They are snmetime.H called (fueoeyiea ("white cells"), 
iKOUUse of the whili>-h ap|K'arance of a mats of them. 

The lymph-vewels which alisorb lympli from the small intestines contain, 
dnring the intcHtiniil digestion of focxl. not imly imlinary lymph, but also products 
of the dijie'livc pioeiws. This niixturi- is called rlii/U, anil is niilky-I<K>king from 
the fa<t tiiiii, like milk, it contain.* a iargi' pi>ipi>rlion of oily material finely 
subtlividftl — piilverixetl, we wouhl nay, if it wen- u iwlid. 

The Blood. 

Like the lymph, the hlnml is a ti^^ne eompiKtcd of eelU and a liipiid Inlercel- 
luLir suhntance. The fluid ]Kirtiiiii is ealliil lir/uor xinif/nhilti {" t\n-\\'[n\<\ of the 
bltxHl ") or plairmn. In it float miemseoiHe iKiMieleri of various kinds j Fig. 4S), 
iif which the most conspicuous and easily demon.-«trated an' the colorless and the 
coIore<l eoquiseles, the former, though without a tint, often being called white, 
und the hitter, though yellowish, red, because, when seen iu heaps, they pn-scut 
respectively ttte hues which these names suggest. 



fiS 



ELEMENTARY TISSUES. 



The colorlfM enrpuM-fen are clohular, jrraniilar, aliont j^j inch in diameter, 
and iw»se*t miolei which are iiidii^tinet during the life of the ^ell■ Al rest they 
display aimeboid movetiieiitH. Thi>^ deficription Mil) be seen to coincide with thiit 
of the lymph -co rpuwles : and tht!- will nm be unrju-ising to unc who hiw Icurncil 
thai the lyniph-wtreani poui-s inwjwaiitly into the current of blood, so tlisit wliut is' 
at one moment a lyraph-corpiiwlf, iit the next, linving entered the hlood-viiseiiljir 

svcteni, ii< u hlood-corimwle. Tlie cidurleM coriiiu'- 
elws ure divisihU- intfi a niimhcr of viirietiw, which 
aro chiefly difleix'titiattnl hv mt-niM of Ktaining tenti^ 
The fohrfil rorjiuii-lrit are very abnitdiint, imni- 
herin(r in'rhajin five hundred to nm- of the on lor I I'.-s, 
and Diahin^ alxint one-half of the vohnne of the 
hlood. They are eireuUir, nou -nucleated diMcw, with 
rounded edfjeii and eentndly depressed ftnrfaee», 
smiKith, amber, tranMiarent, fieiiible, elastio, and 
about r^^j inch bntaa. BesidcH these bodie»> are 
others, niconF^piction*' and wmicwhat difficidt of dem- 
onj-lration. which iiwd not be mentioned here. 

The blood is contiiirKil in the cliimiber* and tnbes 
of the bloo»l-vaM:uhir I'Vi'tom, from which it <Iih-s not 
normally escape, exceptinjj in the (^plcon, where it eonr;«e» in walUUi^s channeU, 
and in the ciu-e of women during nicnelruution, when it Ls difeliurgitl through 
ruptures in the vessels. 



I 






Flo. W.— Blood corjiiisi'i™, Oue 

colMtcM torpuaclc 1> ■ccn it Om 
top: iha othtn ant Dolonid. [Dkl- 
tnn.) 



THE MUSCULAE TISSUES. 

Tissr»i IJkvi»ted 'ro Movkmext. 

Contractilitv is in some de;jn>e nn atlribiite of \-nrioiis ti^uos. Tlie typical 
and oriKinal cell manifests its auwboid mnvenient.i by virtUL' of its ei>ntnictility, 
which it brings to bear now in one dircelicm, )>ri'seiilly in anolhi-r. The cilia on M 
the free surface of an epitheliimi urir made to [lerfoini their rliyihniical l]i>hin^ I 
because of contnictilitv in their ei-lls. But the iniiw;nlar tis>ncH alone dciiend 



U)iun this proiKTty for the sole functional <|Ualily which di''tin^ii-'>lies ihcm. _ 
Their oontnictililv is diHjiIiiyod on a niaeroscopic scale, and residto in tin- active fl 
inovement--« by which liKyimotion of the body and changes in the relation of its 
different part.* are otlicted. 

We dintingni^h ihite kinds of muscle, which differ uuatomically, and, for the 
moat part, phy Biologically alfo. They ari' — 

1. Plain ratii^eular tissue. 

2. ('nx'«-strii»ed rauscnhir tissue, 

3. Cardiac muscular tissue. 



Plain Mascolar TUsae. 

This ti.-wnc i» known by a variety of namox be!*idefl that ju.st given. It is 
called laniKilh, fiir the same ivat-on thai il i.* called filatn, l>e<?ause of the n.snal 
nppearanwr of it.'* cell.-- ; >wn-*friatfd or uiistri)tcd, to (liHtingniiih it from th<- [*>H!ond 
kind of miiiKrle, which is characterized by a rcgnlar cri«i-<'ro)*s of linw on its 
cells ; invaluntari/, fn>m the fact that it is not under the control of the will ; 
rff/rinihi' and the uiuiu-ular finmic of o}-giin!c ti/r, Ijecause it aids dirt-ctlv in the 
performance of (hose offices which are ctiused as vegetative — iu the organic action 
which i^i beneath wmseionsncss. 

It is found, for the most purl, in the walls of llie hollow orpans, as, for exam- 
ple, the alimentary tube, the urinary bladder and the tubes Ictidiiig to and from 
il, and the arteries and vein?. 

It is made up of cells (Fig. fiO) which typically are fusiform ; but thoir ends 



CJt(kiS-STJtII'£D MVSCCLAS TISSUE. 



59 



Mf Komctimes forkeJ iiLxtead of Wing tiingte-piiinlH, and eoniethnes the s|iim1|p 
eliapc is lost liy tht- roiindiug of the extn-niities. ()lu-ii thiTp U oUcrvtHl it tiiiiit 
11(11 M.iiniiH-«- of lim-s riiiuiing Icnfrthivise, as if iin> cc-ll wore- Irving to di'Vclop into 
a i.tH|iitl iibiv. A tninsvcn-c cnl show^ that the wll ha* tiaii'-ntil ifidcs. evitWntlv 
the rusiilt of iin-^'Mii-i- fmni forcible c-uiitart with iu fellown. Thi- txW U alHnyo 
uur'lealed, and ^■■ktuIIv Ih-vuikI cat-h enJ of tlie nucJctut i> n little vollvctiou of 
granuleii. The cell hitH n Jolii^U- structurelv)^ Hltcatli. Tho len^h »\' llu- I'clU 
\-aries betwecii y^j and jJj ineh, iIk- nn-ator imrt beinj; very smnll. In wmi- 

.siliintiiiito, M.» in (he artorioles l!ic felU an' .HciuinLte ; 
hut u^itally tlicy itrc ui^nciated in such a way a» to 
iu:ike bundlirK (jam-ii-ufi) or layers (ulrala), Mng 
united hy n small ainotml of :idh<.-eive mateniil. Th« 
celU are sg^rejfati-<) with much r('i;ulnrity, the hulg« 
of one l)eiiig adjusted to the tnjK'rittj!; ti|)« of its near- 
est neigbboni (Fig. 51). W'lwn dii>tind bundles are 





FN. HL— CtoU* of plUD uiMcultr 



Pn.5).— CMlt uf plain muncular IImuc unnefd In a >Ii««I. 



fanned, thvy an- ti-^ually attached at their extremities to some otlier tttruecurc 
Ihruugh th<i agency of a libroua prolongation. 



Oross-striped Muscular Tissue. 

This ^1trietv, aleo, like the ))l:i!n. hajf a niini)H-r of otlier numc!^ : xtfWyW or 
stri'iteci, from Its mieMst^jpio njiju'sunnw ; VftfuiiUirg, Ixx-aiwc the tintst of il ils 
under tlie control of the will ; tin- inuM-ufnr tixitai- aj aiiimnl lijr, hvtmttfv, while it 
has little dirwit eflW-t njmn the oi^mH <.f llie veRelntive fiiiurtiotiit^ il i» Inf^ely 
cuntTrneil in tlioH- man i filial i<>ti:> which iiiv (M-culIar lo uninmN. Thi* liwue 
make* n|i » vi-ry ixuwidi- ruble [inrt of the liiilk of the lnwly, i> itrinei|ially eon- 
iH'ete<! with the i>ony skeleton, and is that inalerial whieh, in <ither nuimmals, U 
callni '■ fle^h" or " lean meat," It i^- ecmimonly found in coherent ma*«es, of 
varvinjr hut de6nite shaiM>, each of which, taken in connection with a Hbroiis 
[intlongation at each entl, is known as it muscle. 

The liistologicjil unit of croiw-striped muf-cular tipuiic is a ni'iwf^-fibrr, which 
is the liomologiie of the cell of the plain muscul.ir tis>-ue. This fibn- is like a 
lou^ cylinder, with Mtmcwliiit flattened sides, and rounded or e<>ni<'nl einU. It is 
ontpletcly cnvelopi'd in a very delieate sheiith, thv lutrtyi/rniimi ("thf Ui-«li-liii.-k "), 
When exjiniiutii iin<leran ulijeetive of inmlenite |>"iwer, it jiwm* to be iiiiirked witli 
(Mic.ite, Itiii^tndiiuil, jKiriiliel, iiii<l ettuidiitttiiit line", and with bnickd, 1 runs verse, 
re^darly placed l»andH or :<tri|K')', from whieJi tlie ordinary nnmeit of iitriatcd or 
MiriprtI (l>elter, cnici»-f*lri|iod) originate (Fig. -Vi), Uetween (he-se ero?is-stri|»es are 
liybler are:is, which, with a stmnjn-r objective, seem to l>e divided by a fine line. 
The cause of these pwidiar appeiirnnc<-s is not manifest until the tis»ue is studied 
with a mieroseope of ^;ivnt |>ovver, but then it is found that they are deceptive. 
There are no eontinunu- bands or lines running transversely, inn! the appan'nt 
breaks in the longitudinal continuity of the cross-lines are an ilhiKion, aiu.'^ed by 
tfat> extreme finetK>ss of the contmetile material at n-gularly alternating intcrvaU. 
The accompanying diagnim I Fig, olil will itluKtrate thi*. The Ubn- i» in'presentwl 
as eom|H)»*ii of a wrief of thread* pliietil side by "ifle in longitudinal rows. Each 
of thes4.' llimids in a fibril {fihritlu), iind \< ni:irk<-ii by itllcrnalini! bulges and con- 
Btrietion*, n-gtilarly placed, and nmingvtl in tlie foiiowtng onh-r: a long, wide, 
fusiform l>ulge, a eoui<triction, n i^mnll, globular bulge, a constriction, and eo ud 



^^^^^jlH^ 



60 




ELEMKNTA R Y TISSUES. 



fmni uDc end of The fibril to tlic nlh^^r. Or, to put il in n (litlVrcnl wiiy, n ftliril 
IomIu likt? a fim? ihrutil, ii)«m whu-It an- »tniiiir Inrp-, .ii>iii<lt<-^li:i|)iil lii-mi!* ;itnij 
email, rdiiuil tieatU, reRiilarly altfrnatiii);, ini<l kiiviii^ a littk- oi' tin- ilii-^ad i-x-f 
pi)wcl W'tw'i'on «ic|j lieati ami its twii ni'ij;lil"'rs. TIicm- liliriU do not loiirli cac-h 
plliiT, but Iwtwti'ii ihcm, and also se])araling ilitm iV>iiii the i-nrcolemnia, U :i ihiii 
'" obiilih- Hiiid) siibfltauw?, called mircoplaem. The liurili' are the contractile por- 




Flfi. W,— p«n nf a nlim t-f ■■ti»«-ilri|>i-tl mtiiciilBr liHlic 



Kio, S3.— I'liit'i"!" ■Ui'" '"I! <Ui- ininiilcMnie- 



tion of the fibre, and, when they contract, their epimlki? and \h\uU >'horten in the 
line of the lonj; ax'w of the fibre, anil ^^ve!l out in the liitrml direetinn. TliiB 
cjuitcs a displaoenieiit of the Kireotild-^ni, wliitli, (■"ii»i|iii-iilly, piiKlic'f mil llic 
Karo^lem run, and thus produce* itpiilnrlv jdawd pinlriK^ioiii^ alonft tbi: Mirfuce of 
llic libiv. 

If iIk' <liiifjniin 'k viewed at a distance (as acn«>.-< the room), vhich will 

olisi'iire ><nii(* of ith dciailn, the 
effeet » very like thai produceil 
by the examination of a fibre of 
mu»ele «itii a miero^ope of mod- 






Fio. U.— Prarmcni "f « flhi* of 

«DM'*lr[|>r<I init>i-iiUr tlimc. xlioW' 
unt niirlli toixntml lU uiio end br 
UMlni- 



FtQ. SV— Knuoncn 1 1> f n fl lir e 
of crvn>itH|>«l iiiu»fuliir 11«- 

V47nc clOTiue. I KOllllii-r. I 



Fin. ^-Tnnivi-nc trciioii of 
unnclV'Hbrv.iiliuwIiiti iiticlcl. iTn*- 

tut, I 



erate powei 
nra 



faint, longitudinal line* and l>niiid. tran*verBC i*1ripes, tlie latter sen- 
XvA bv Iipht iiili-rvaU, which an? cron^-d fn>ni "idc to side iiy a ihin, dark streak. 
The ("pindle |Mirtion of the fil>ril ii^ ralhtl a wovouji elfm<-iil ; the round bcwls 
in a sinirlc tnm^ver-e plane conrtitule what \* known iw Kitt'i^'* membrane. 

In ihi* u-a-'inj; of a bit of miioiiilar ti.->ue with ne<-<l!cji, it hapiienti that niuiiy 
fibnii iin- lorn, and the bn>keii vmU of the tVagincutA a>nieiinies arc frayed out 



CARDIAC MUSCULAR TISSUE. 



61 



like a oonrse linish. the fibrils standing for the brietlofl fFip, b\). When the fibre 

bas been harden^ by certain reimentit, it will ocrai^ionally i^how a rro£N-flea\'a^, 

by whidi it \^ <livi<liil into tWi^a (l""ig. 55). 

I.'|ii>it die inner i-nrfni-e of the «»rp(>leninin are scattered a miiuber of ova) 

onclei, the mHi-rir-i'orjninr/rx I Fiji- o*i), «> MiwblriHive tliiit they (jeiienilly ch^])c 

obwrvntion tinl»^ n-ii^'tils are ii>^-il iii tlie cxamiuutiuD. They urv ri-jj^anled a» 

nue1eale<l iu-ciiniiil»li(>ni> iif the ^re>i|)1iinm. 

In a film- :in' many ^niti|H nf fibriU, e^fh (N)lle4!tii)n Ih-Iiii; cjillcil a mtmeir' 

frjumn. The libfir* iire aggrHgattti in biiiidlfv- (/(Mivch/i ), ami llif ltiiiidlt-> are 

ftv-t<ndiliil in ilii- ei>niractilf imriinn of tin* niiL^-le, The lilir(« niay be '2 ini'lia* 

ImiK ami yjg inch ihiek, or only a tenth jiun of thi'se nic:L'4Uremeiit!i. In niu-icles 

or to-tfieuli whose length is greater tlian that of their ei>nii>onent fibres the latter 

arc joined to eaeh oilier end tu end. Fibres commonly do not branch ; but Jn 

some of the lingual and facial miL«cleit tcrininnl divi§ioii8 may Ik- observed. 
The fasicieiili, -.i-^ a ndi-, run ffoni om- end to the other of the eontnictile jjiirt 

«f « mu«'le : bill exception* fxtnir in doiibh'-lK'llied iiiuwics and in others which 

have a tendinous intemiplion of thi- miisrnlar ctmtinnity. The fnwicnli, from 

the clownfw with which llicy hit [tackiHl, haw flattened sides, Hnd an- thus uioru 

or Iiiw iirij<nn>id. 

Ast lia^ been wiid iil>ove, ejtch fibre has, aii iti* true and perfect inveHlment, the 

tareolnnmit. Between the Hhre^ U a delicatt^ areidar ti.Ksue eiiiiiiniinii.-< with a 

thicker layer of the ^nic, which nheaihi^t the fasciculi ; ami thU Li merely an 

inwani prolongjiiiim of a siitJ more pronounced 

lamina wUieh coat;' iho entire milfiele. The outer 

tunic (Fig. o7) of tllc muscle is called rpiinyninm 

("upon niii-^rle"); the i>lieatliH of the bundles 

cnni^tittite the prrititi/sitim {"around muscle"!; 

and the tissue Iwtwceii the fibres i« the inniomi/g' 

turn ("within nnisele"). All of thcw? are eon- 

tinuoiu, each with the ultiers, and all are ei)n)|Hi«ie(i 

of arei>hir (l«siic. 

Fibrcf which end in tendon come to it either 

in liiM- with itj» axis or oblifjncly to it. The sar- 

nileniniu of (he end of the fibre i" vcrj- closely 

iin;ichi-d to the leiidon, and there U a continuity 
tif the anndar tuwue U-twcen the fa.>eiriili of the 

ma»ele and that belwcin the bnnill<'.-> of the tctidoii. 

In ih&e ways the two parts of the miwlc are «o 

(irmly nnitetl that their Reparation by viok-iioe ii' 
extremely rare. 

The blo<Kl-veM>el<t course lietween the fibres in 
the areolar ti-nsitv, making a network of lonj: iiKwhe;*, Lymph- 
atic^, nlH>, are inimenmN in the areokr tissue, and the nerves 
of tlie niuM'^k- arc abundant. 



Cardiac Hascniar Tissue. 

The mntwular ti>isiie of the heart has jweuUarities, which 
ally it to the plain miiiH-ular titnie on the one hand and to 
the (-rfw^-strtjKsl on the other, II is- like the former in being 
ComjKwwl itf nncleatcit ceils, and in Wing twyond the control 
of the will ; it resemblet; the latter in being cnji^s-titriped, and 
in pri'wenting in a manH a color similar to that of vohnitary 
mnsele. The eella (Fig. -W) are sliorl, bninched at one end, 
<>r> !(*«-!* triped (Ihoiigh with le-t^ regnlsirity iind iilninnc^M than 
to the ea.-e of onlinary striatal miwele), and arv not fur- 
oUhed with sareok-mma. The eelU are connected with their 




«uc 111 crua -H'tlion, Tli. "lu-i ulnr II*- 

liy llw ("[■i*™ (■rl«rtfii IIh- imnlilon* 
f>ut4Mc of thv cnllrr niti*i^l«- if r/iMiv*- 
■um; bclvctn lllu hliii<ni> It pnrnrlir 
titntt b4.|*v^n the t\hT\-it in < n^mNVrtwHt— 
Oir IahI nhciiA II Iji Iwo nrrfu at th^ rinht 
nUiimniiKlIc, iK U. a.) 




Fig ».-<*U 
muwular Uuuc. 



ofotMlaf 
(Tntul.) 



69 



ELEStEXTARY T/SSCES. 




neighbors hv an abrupt union, and runii ra.«riciili and in>tH 
warks (Fip. oWi. The canliac musriilar t\»^ue has a reninrk* 
ubly abundant supply of bhtod- and lynipli-vessels. 



THE NERVOUS TISSUES. 

TlKiliES KsHKVriAI, TX) Sessatios. 



nndfip^B 



I'li. ''.< '■■ir.llii 

fulur ti»uc. tlii^ ccUt II II 
Iwl Inmii'liiorli. (Ti^iiii 



The iiprvoni* n]>{)uratii!< i* convcnicnllv com-idcrcd under' 
two hitidw — th<; central pnrlitui nnd iho ]M-riph('nil jHirtion. 
The ti>rmer coniprisaa t\w brain and npinul conl, and is 
otherwise known a." tlw- (*rebro-spinal axis : thi- hitter in- 
< hidfs thp cords «hich rmiiaie fl-oin thii" axis, and iilsn ths^ 
franglia (" knots") ujKjn llxse cords. In Ixuli iIh- ■(-iilnitV 
and the peri |)li end rf]U'ii>ns two kinds of ti.s.-ue are recug- 
uized, wliich are dietinRuisht'd by their color as gray ami 
white. The white ii* iniieh the more abundant in liolh 
ri(;ions. but llicri' is u f!-n-ot deal inore of the gray in lli« 
riiitiid tbnii then' t.* in the jieripheml. Ftinelionally 
reftanlwi, the gray matter is tli-il wJiieh reevives impres- 
sions, retains, wnvorts. mid marshals them in variolic ways, nnd origiuaieii 
impnl:>e.s : it i^ the [Hiri which feels, thinks, rememlM^i-s, wills ; the white matter 
merely eon vevM impn-tiKioiis and impiilsee, connecting the (iniy mnlter with distant 
jwrts and a-*"oeiating one portion of it with another. The gray is <vllidnr ; th« 
white is made up of l!l>rc-s. Ner^'ea consist of fihrel^ of this kind, gmnjuil together^ 
in bundles of small or large size. f 

The ffray ncn'oiut (i-mwjt i« eomjKj.icd esscntinlly of cell«, called nrrvc"filii or 
gnnglion-eelU. The^e vury grt-atly in i-liape and size in dilti-rcnt [larts, but 
ihey all haw ceriain eommon features which are elmraeteristio. They are 
granitIitr,.nneh-ftlL-d, usually pigmental, and have jirojertions or processes which ^ 
anf eall<»l poles. At least one ]M>le of a cell U prolongeii as a nerve-fibre (l'^i|r<fl 
60), and ihua it is seen that there is a structural connection betwecQ the two 




Fla. en.— Nstvp'MU. An orthc [ovccbm aro protoplumle axecpl Uwt muked a, which li Ui«uiti«xllnil*i' 
pMoeai fr InillralM • clump ef ;)l)[iiioiit-gnnulM. (QcrltCltJ 

kiniL* of nerve-r is^iio. The other processes of the cell — of which there may \m 
many — radiate fn)m it)t general mass, divide again and again, and terminate in 
minute twigs, which mingle with, but do not become continuous with, corre^poud- 
ing raniitications from neighlH>ring cells. The«; proccsHjs are culled protoplamiic 
processes or iteitdrileii ("tree-like"), A ncrvc-ccll, with it* ilcndritcj^ nnd thft 
nerve-fibre which is continuous with the c«ll, constitute a nntron (Fig. 81). The 
neuron is the unit of structure of nervoiw tissue. 

The lekitf n^rtouti fiteuf (called white on atTiiimt of ilie appc'tinuiw^' of a mnsa 
of it) is made up of fibres whicli varj- in diumeter and length, bni li»ve their 




THE XSRVOVS TISSUES. 



63 



■(■vt ecu. 



■ANce 
kKik-cfuHoca. 



T^omeniTti. 



■■(•^cvuHetN moeiai. 






•■lATH. 



^^tain di&ivuce in the prcseiiot.- or abmnvc uf a txTtiiin oMt. Tbp v^impk'st, 

inae least clotliiKl, of ihp fibn-« un- tmiulJ, pule, librilliiK^^I, iiiicluiuil tliri'SKis 

'^of li<MMip, n-)iu4c oDiptim-iit fibrilliv lire iIjc niiiiiit«i*t iiidoiB^iiiifiitly n-vOfiDiaiblc 

portion? of till- ti**iH'. Sik-Ii a tlirenil h valM a ^Wc _;iwr, anil al^o bt'srs llie 

Damp " niiH-im-fliilliiiMl," on 

Kcroiinl of till- liu'k of llie 

tiiiiti- \v|]i<-)i <)i^(iii^iii>lK?i tlie 

other kiml. It »i*mU otl* mi- 

nuii- tilunienti nt a right Diigh.* 

willt iiH .viur^' wjon atV«r 

emtTpinjr tnnu tl»* cell, ami 

then coniiiiiifH without fnr- 

lIitT branehin}; milil tii-ar its 

PD(I. where ii iliviikT^ into 

ban<IIe<- of HbrillH-, out-h of 

whi«4i »|>lit« u|> into ^miillvr 

huiulles nml M' on, iiiilil the 

fibrt- hii"!' fnm-d nut into it* 

uhiiimU' Itliiiiu-iitK. 

Bo:<m1<s« th<- \>n\c llbriM iit 
more iianiemtL^ <■la.v^, calKxl 

lpAiV# or metlaltaietl Jiliren. A 

ij-piral rt|ire§pntative of this 

varieiy ban ihreo {xirls, of 

which ihe first and esfienliu) 

i'' ecntRilly located. aii<l from 

tiiU fac-t 16 namixl the <(j'i'jv- 

nfiindtr faxii«-b«nd or axial 

fibn.'). The axU-cvliink-r is 

Llilcc a pale fibre, bein); fibril- 
laleil, ^ving olf fine, latenil 
twip> war iiis origin, and ili- 
viiliii^ inlu it" iilliiniili- tUiril- 
he at iu iM-riphery iu the Niiiiit 
jDana<-r. 
Outride of the axis-pvl- 
inder is a ihitrk, hi'iiiliitiiig 
tuiiie, conip<"^d of a (^oft, oily 
material (ntyelin I, and known 
a* the tnr'ltiltaiy nhetitA or 
while ^ubotanoL' of Sciivrani). 
SnrniniHlin^ tltif finit <vat is 
a six'«>nd, very flelicale and 
thill, but Millieiiatly strong 
(•> kiX'ptlu! iiiiilnlliity ifht-ath 
iu HtiajH-. Ii i:< called the 
firiikHiiv iihmlh, nrttriUtnmn 
<" iwrve-hnsk "t.or niiolented 
Nheath. The mcHlulLir^' iilieath 
is evenly spread iijhhi the 
axit-eylinder, exeeiitinjr at 
nynlar iniervals. where it is 

larking for a minute ^paee, thus leaving the primitive sheath as the i-o)e ooveriu? 
<>{ the fibre. At tl»>e [ilaees the fibre pre^-iit^ the appearance of beiiijr eiicireleu 
with a cord ;«> tightly ji- to wjueew the medullary suWliinee away from ihe jiiiil. 
Tfie«c «'on>flrieli"iis are Utiowii as llie imtfru nf linnvii-r, uml the lengtlw uf fibre 
betwfvii iheiil are euUed the iiitrriiotleii (Fip. til). 



■Xia-evt,>HD(a 

ClOTHIO WIIH 

MIDUlKfl' - 

■HC'To ana 

•■IUIIII.CHMII. 



CLOTHCfS MriTH>»{ 
NIUniKHHl J 



uik-eiuiretii. 




TCMWiNai. ■■■««Hia. 



riu. tli—i neutnlL |lil4tir.) 



u 



ELEMEXTARY TJS.STES. 



The primitive ehoatli lias on \t» iniRT Mirl'iiec- n iiuolviu 
midway bctwct'ti llio endc of thv lutttrr. KJtlK-r or Ixith of the ^luntlii> may he 
Inckiii); : nnd in the luHcr t-aw thi- axis-oyliiuliT alone U loll, nti«i w*- liiivt- u |mli' 
fibn- iiis(i'.i'l i}( a wliiu- tmv. In brii-f, llu' axis if nlwiivs jirespiil a." Ilu- une 
viiiicntiiil lliiuj; ill ;i iii-rvX'-Hlirc ; if it im coaHii willi llic ini'diilliiry sliraih, 
it is u wliiu- Cthn- ; iind il iniiy tic in hhc imit iiiiIchI ami in atiotlx')' i-lmlioil. 
Tlii'iv i> nil l»rrai< in tlii- rfniiinuity of tin* iixin from one mil to tlie other. 
Till" filntiu'iitji or lU>rillie composing it are lieU togetlier by :i cement called 
linirtifilriitiii. 

A nnintter of norve-fil»res jpitliered into a coherent hnndlp constittitefi a. /">(?"«(- 
tiw (" little roi>e "), It is enclosetl in a sheath of laminated fibrons tiwue, called 
jierineurium ("unHind nerve"), from the innermost layer of which t^helf-liket nibec- 
uUe project l>etweeQ irregnUir jiroiijw vi' iiervc-fibret', and eoiii|)one tlic <tiili>uriii-inin 
("within nerve"). A single fiinieiilii^ with iti- wrtijuiinjp; may constitute a nerve; 
but usimlly a numlKT of fniiienli are griiii|Kil top-ther in a nerve, and, when this 
obtatiu, they are kept in eiose rehition to euch nlher by a common sheath, tlie 
epiufurlum {" u]»m nerve"). The bundles in a nerve have a network nrrnnp-ment, 
each funicnhis siiliitin^ up more or less at short intervals, and IIh eompcinent fibres 
paviin^ into neinhbca-iiif^ fnnieiili (Kij:. 62). 
Tile tibre.*, however, always retain their in- 
dividnality : while they cross and reerosH 
in the nerve, and any one of them may be 
an ingredient of many funiculi in ]HUf«in^ 





Piu. «.— Connrrtlon between (lie bundlM tn 
don't- IDalion,) 



Tiii. eS-— BntioliliU! cif fl nerve. tlHilioii-) 



from centre to ^leriphery, there Ir never any ("Oiile^vnee Itetween them. In the 
hmnchiiig of nerx'es the same rule i.'* observed : a fiinienliis lets some of its lihreo 
switch off at the side or separates them into .'<nbstantially eijnal parts, l:iit the 
fibnw themselves remain undivided (Fig. 63). The larger vesself of ji nerve 
conrwe in its sheath, and the enpillariei^ are arranged in long meshes between th« 
fibn-.«i. The epineiirinm is also supplied with nerves, called mrvi neironnn |" tlic 
.nerve* of the nerves"). 

The origin of nerves varies with their finietion. Tlwioe which convey !mpiilM« 
from the eentn- to the periphery, called 'ffriynf iirrrrKfrneiininn "carrying from"), 
grow ontwanl t'nmi nerve-eells in the centre ; while those which convey impres- 
BJons fVom the jieripherj' tn the centre, e-idleil n^rnit (nieiining " carrying to *) or 
sensory nerves, grow inward fi-oni nerve-relN in organ.* of s]>e<-ial si'iise or in 



MEMBRANES. 



05 



'"■^ 




¥: 




"T-. 



I'm. CI.— AmnKcmFiK vl UFtvc-«ilb And 



y\wM- fihrt^ bmnoli wtthiii i\\v nt?rv-<?-oentre, and send dieir ultimate 
i\v\p> anioa^ die celts, but iln not unite «-ith tln?m. 

(iangfia ("klMtls") are Imnolips of various mw??j ottntrrinj; in the course of 
nerves. Thpy are made up ot" Dcr\'e-<i.'llji anil llwir covcriiiK^j nuiased upoti and 
between the tibnm of Der%'c» (Fig. 64). li^ivh 
cell of u gnn^lion lias unv or niore nKi»K;vl- 
ioder pnicese<^«. wlijcb lire ■iniiiui^'il inio 
ner\e-(ibrc^. Tin- gnD^linn it ciolbi'd with 
areiiliir tii^uf, wliivli m.-ihL'I tnilH'ctilit- tiirougb 
it in rverv dini'tioii. 

Bel<>r<^ rtiiiiiiii; to tlit-ir (n'rijiberal divic*- 
i4>n ninny nit^liilliiii'd rit'r\'e:i Inne X)vAt white 
siilisiaitee ; hn) others n'taiii it during i^evera! 
sinecii of hranehing,. and in these last the 
divL-iion taken pUn'e at tuhIoh, After the 
dihiipiK-arani.'e of the nieduljiiry sheath the 
primitive ■^hi'atb continues for a variable 

Afrrmf (ppuwry) lurvt-n Imvo vurioui' 
]irri))]ienil h-nni tint ions. Sinie of tlicm end 
m ecllis otb<rni in i^iM-ciiil oiv«»t:, a?* tautik- curf>u«)elet<, end-bulbs, and Pm-iniuu 
l>H|i«#. The-w will Ik- dc-'cribrd in llic ebapler devoted to tlie orfian^ of the 
Bi'ii?iv. Oerlain iifl'i-rent m-rvi-n i-nd i«'ripiierall\- by the final i-ppaiation of the 
ajU-t-ylinih-r into its eoinjHiiieiil libril.s, \vlii<-h run betwiin the tl^uc-elenientit, 
and jfeniT.ilIy either end there oi- elso pc-n<-iratv the evlU. Thf sensor)* ner\'e- 
vDilings in leuclmts are often nuggesiive of th« ending fif tnotor nerves or volun- 
tuf^' muscle, to he depcrihed pn-sentJy, Clow? 
t» the musele proper a mi'diillated fibre j>as.Af:i 
itilo tliu tendon, djvide^ n-iii';!ledly, and tin- fil- 
nnienls of the asi^-eylinaer jjenetrate widt'iy 
into the tendon. 

^erenl nervfn tmvc dtfTerent endinjp* ae- 
cardiitf; to the x-ariety of tnusclc to which they 
arc diiftrihuted. In the case of the plain tniis- 
ffiibr ti»,<ne the fibrillar of the nerve are brou^flit 
erlikw- to llie mii*«-Ii-<x-ll«, ufli-r the nervf tia* 
formed a piexnc in whieti ganf;li'>n-eel|js often 
neeur. In eanluu' n>«i«.'U" the mrrvouM fitiinient^ 
pomc fnmi a long-nn-nhed pli.-xiiK, an<l are ap- 
plied to the etmtnteiijc tiliriej>. Kinully, in firX- 
ffltwl miLsele, at^er tin: fiirination of n ehw 
pli'Xii^, the nerve loseji its whili' sheath, llu' 
axii--cvlindcr enter* the ninsriiMibn-, and jiist 
IxiK^th the ^^reolemma .spliti^ up into its tiliril- 
lit, whieh spread out in u thin nia.tA of gmnular 
matvriH) ill whieh niH^lei ure cinljodded. This i>t the miAorial etid-pUOe (Fig, 68), 




1']!^ «t.~MMlorl*l rnd-plaU'. (he Uiml. 
luiiarlu. <T«llit, ) 



MEMBRANES. 

In its wideiit mraning the word " niembnui«" 'nt ii»ed to deitignatc any ihin 
cxiMu^ion of tissni', either simple or <rompouml. TIiils, wp speak of the perios- 
t4.-uro, the eoverinff of lione, as a fibrous membrane; we oalf the layer of cells 
beneath the epiibeTtom of free surlaeea the basement membrane; antia structure 
compor^tl Inr^'ly of bloiMl-ve^eU may lie known as a vascular inembruiic. But 
in H n-Htrieled, although the commonest, sense the word \s npplied to ii bruad, 
Kheetdike orfpm, with u free (unuttuched) surface, furnishing llic eoveriug uf a 
i 



66 



ELEMKXTARY TISSUES. 



piirt or the lining of a cavity. With the hitttr pignifiration the tirni is 4-iii)>liiv<.-dj 
in this scotion, i 

The tyjK.- itpuii M'hirh nil of tht- niombtTS of the proiij) art- timwtrimwl ctMn^iKts] 
of ri foumijilion of wliitc iitiil yrllciw (ilm.ii!* tisKiir, whiili i.-^ limllcil munnl the 
frw MirfiuT l)y a MnRli' l»v<r of viry tliiii, plutc-Iiltc ctlU, iind ujKm thin lust an , 
opitholiiini (Fig, 66). Tht? fihntns ti.'<:iu<>H urt' ti-Uwl into a Ijiypr oi^variahlp thick- j 




Fiii, K,—\ Iji'ltttl uu'iiihrBne In vcnlcpil icMIoti. iF. H. fl.l 



naui, strength, flDxibilitr, and i'Iu*tioity, nw^uiling lo tin- |ini^KirtiuTi jmhI urrnuge- 
niont of it>« ingredients, ii»<i {>< wdli'd tht* cw/hih (" h--iifhiT"l. The Inniellu of 
fhttt4.*ned i-ell>' Mirmoiiiiting this is roally ii )i:irt of ilu' i-oi'iiiin, for it I'onHetii 
merely of eclU of llio wliitt- tihrous ti.-^^ue, Krciitly iitLiiitiiitcil mid lullieriiig to J 
esteh other 111 tlieir odgitri. It i.'i termed the rKixi-meut iii'-iu/iniiii'. Kitiidly <iinies I 
the rijifhflium, wliieli [iresenb* Upon the free siirlace, aiul niuy Iw eillwr itinii)k> or 
llified ill inunlii'rle.-^s hiyers. _ 

111 intist i'!isfTS llie attjiched snrfiiee of the nt('nil)rane is conneoUnl with Ihefl 
'Underlying sinirliiii's hy iirei)hir tJMiie, ahnudiinl or .Tanty, whieh |ierniils sumo 
gliding <<l' the ini-inhmne on the siibjaeeni jiurt*.. This areolar liw-iie is ealle<) 
snhserons, stihtiiiKinis, snheiitjuuinis, nnd so on. aeeonling to the kind of niein- 
brane nmler which it Hen. Tlie hue helwcen it nnd the eoriiini of the nienihrane 
b not exiictly determinahle, as a rnle, the two Htructnn* l)eiiig made of jireeiccly 
the Kinie materials, differing only in their mode of arriitigenient, nnd gr.idually 
sluiding from one into the oilier. \^'hen the nK-mhrnne is (leelt-il off fnmi the 
areolar tissue its under snrfaee is flocciiU-nt, on neconnt of the attiiehmcnt of 
bundles of the Hbi-ous tissues of the latler. In the areolar tissue conn^e the larger 
vcjwflfi un4l nerves of the region, sending thoir bruiieiiM to, or rcwiving their 
radiele)> from, the eorium. 

ThiTc are four elnwics of ni(.'mhrajies : 

1. SiToiw Memhr.inPK 

2. KynovinI MemhnmeH. 

3. MiKiiii.s McinhniiK'<. 

4. CutuneoiiM Meinhruuc. 



* 

I 



SEROUS MEMBRANES, 

Of nil the mombnines, the serous (maiil/nrnu- h-i-'imt) are the simplest^ — the 

nearest the tyfK* which has been descrilx'd. They 
are nlways moist wiih a fluid very like blo<Kf- 
tu-nini, an<l from this faet they derive their name. 
They are thin and tninsparent, [KTniitliiig a 
view of the imniedirilrly itiihjaeeiit ]iar(s, fairly 
strong, eonHiilering their delicjicv, and some- 
what fWiie. Willi a single exception, which 
obtain.1 in all feriiah's, but nvver in males, the 
serous meinbram-.s are shut snes; tlmt in In say, 
they have no o[>cning by whieh they cominuni* 
cate with the surface of the body (Fig. 67). In 
the simplest of them this ronditiou is so plain 
as to be easily understood ; in the most com- 
plieuted it is not especially dilticult to dcnion- 
stratti, even tJmngh tlie form of the membrane 




Flu. ST.— Dlkcram 
SMU Of k MKen* iiR'ubricic, 



Thc brolcrri 



UM npnHnM IIk.- tnuml>mii<i lliiiiix the 

(DoMd n^tj. if. U, li.i 



SEROt^- Jfh'MURAXKS. 



07 




Fio. ML— IM»E«irL ihnwlnnlliat "hm 

ntiily. It *I111 o'lmlii' "iiUlJi- -'f Uii' 
Htcnu nu^'imiii', Mhlfli iIt''i It mi 
cxicmtl tunle Mhllt^ coiiIluulliK to tins 
iriuMvity. (F. K.(i.| 



sajtipwln but rt'inoli'ly lluit of a i»ac. hi ilmsi- wiiicli Hn' timnifiwlK" bag-like, and 
whicli funii-'li a (-i>rii|ilc((- or iKirlial (HNitiii^ to ititiTnitl ni^ii.-*, two |kar(h an* rec- 
■.^i»sl — iliat H'liii')i i-> iitiHrliiil to itif vi->oiin, ami ihiit wliioh U la^tfiicil to the 
wullfj of iIk- Kiviiy in wliirii liie organ w ooHiaiitHl. Tho foriniT \n called tlie 
viunrtil fngrr, ih(- lalU^r tlie paru-tat ("on th« 
wull") or rfflftieit fiortion. The relatitins of 
parKt will lie easily oomprehendeU by refercnw 
III Fijr. 68. 

Ttic tlia^ram rrpre^-ntfi u vi^-tu: pui^lting one 
wall i\i tltc scntiL'- 'io.v itiuTin). t!)ti>^ mnkiti); this 
portwo 6*rvf as a tnnic li>r (Ir- or^iii ; vonsi-- 
nnenlly, this is tin- viweml jiarl. Tlie otliiT |«>r- 
ttoii of tho Mw liiiwf llw^ wall of ihc «ivity in 
whivh (he vis<iiii now ik o»t^lo:4e<l, and U, tho re lore, 
tliv [xtrielnl giart. It i.s tint a^vtertetl that ihb in 
tin- pnViM- way in which ihi' vi.-uvra procure their 
MTou." tiMl ; but the condilifin which exists is mifh 
a.-i w<Mil<I obtain if iJiis prix^cdnre were actuul. 
For the sake of oWrnesH in the diagram, a 
cavity is repnesonlcd between the enithclidl sur- 
face of the VL>i«-eml layer and thiit ot the parietui 
layer ; but, as u mutter of fJiet, l)i<' two Inyei-g are in actual eontaet, and tin- i^cruiw 
cavity, of whieb mention is often riiaile, is not real, but virtual, 

Scronw nieiribninew pn-«ent many fnliN, wbieli ci>nnect viiiwrn with iwli nllier 
or with ihe walls "f a laivily, or Mmply project inlo ;i estvily and rclnrn un iheni- 
MdveH, forming a ta.<^'l or an apron. A nerouK membmne may line a tIbrouH bag, 
and 1)6 relleeteil over the -lurfae^' of neoniaiiu^l vi.seikt, and in ^neh can^. i.i denom- 
inatcil & fihrn-ttertniH titemheaue. 

Till- •yirium i.-> thin, but. contiiiiiH I)liH>ii-ves,».eU, lymjdi-ve^.iel:', and lyniplioid 
and adijMwe linsm-s. Tin- lyinplmti<'s aiv e--«|>eoiii!ly abitmbnt. The nervoun niipply 
iii .■■nuill and h sympaltieiie in origin. 

The eftilficiium (Fig. 69) is always single and tLittenetl, the cells having irr<^ 
tdar, iMitehed edges and fitting aecurately together, 
except that, at intervals, little a|)ertures are found, 
some of which are the Ixjjinninjpi of lympb-vea- 
wN, and from lliii fiwl are nuincd idonuitii, from 
the Orcek woiil for " mouth ;" and others are 
filliil with priH'iw*!'* from celU in the eonnni. and 
hetRT iin- allied [intwh-tduimtln (" false monlh!i "). 
Till! true stomata an* <li.stini;niitlietl by a little 
botimlury of ck-IIs, mu<-h sMiiiili-r than ilioNe fiir- 
ni.-ibing the general ^urtiiei'. The ilemon-ttralion 
of tlieir iramiiliate conrnvtiou with lymph- ve-tsels 
led to the l>elief that .-.ernuH meiuhmn<?< are only 
cxpansionii of lymphatics, and, consequent I V, are 

to tK' rejtiinle<l as belonging to the lymphatic system. Their physiological per- 
fiirnianec uml their behavior in fliseose siip|M)rt this theory. 

The tpilhfimi eur/nce i- piirtieularly smooth and glistening, and thus the 
gltdinj; of opjHHing porlion-* is awvimniished with very slight friction, which is 

rtill further ivrl ij by the presence of tlic thin Hnid constantly seeretet! by the 

wllp. This lliiid, which Inhricatcs the membrane, is normally present in so small 
nn umotini lluil it merely moistens the siirfatre. Just as fast as it is formed it U 
withdrawn by the lymphntio:* tbnnigh the ^tomntti. But, in disease, when the 
efpiilibrium lietween seen-liou an<l aOHorption i> so distiirlied that the lymphatics 
do not i:arry the fluid away as mpiilK' as the cells nmnnfaetnre it, an aeeumnlatinn 
occurs, the parietal Uiyer is pushed away from the viseeml by the inter\-ening 
liquid, and tu thiB way the virtual cavity is converted into a real one. 




rui- W.— I^rl ul trre (iiTlhr* of ■ 
nroui miniibniiie. Bhowlne tho Hal- 
tunod epUlitllal cclla ■nd ilxe rbnnua. 



68 



etEMEyTARY TI.SSl'E.^. 



Berons membranes may be divided into toicrably distinct classes, a* follows : 

1. Seroiii- membranes proper. 

2. TIte lining menibriino of tin* viineiilar cyi^tcm, 

3. Tbc liuitii; moiiibrniH* of ccrlnin <'nvit.ii-H in siiMfiititciilflr lixiiieti. 

4. Tbe lining nR-mbmiie nf ttio cavity of the c<^r(fbnt->ipinii) axis. 



1. SerooB Membranes Proper. 

Under tliis head are iticUidcd the vnrions mcTiibRini'N wliiili result fomi Oi« 
division of ibc orit^inal »tToii!» mfnibnim- liiiiuji tin- tliorikrico-^ibtloiniimt oivitj- 
(Fig. 70). Tliesc are derived frotn tlif single sm- liy eon.niriction, llic flioraeic fiist 




fininki An-ff At 



riHru 






firCMnm 



TWnirw t'aijiaaliv Teituin. 
Fiu, To.'WKiraiD ■howlDti romiatlon ot uTDnl Mamu «ki trvro the <>iii' <'riKl<ml t»e. (After acgRubsJici.) 

being separated from the abdominal, and then siiIxltvisioiif« of encli of these making 
three dir^tiiiet saes of the upper grand division — the two pletinc and the perlair- 
diimi — itnd three of the lower gniiid divi.-iioii — the peritonciim and thf two \figiiiat 
tuoie-s. Thci- nn- ealleil .leroiis iiK-nibniiies proper, beciniM- tin y present, to an 
extent whieh the other.* do not, Uie (Valiires whieh have been nu'ntioned as eha- 
nicli-rizing this class of structures. The pleune cover the Iiuijib and line the 
[K>rlion« of the thoratric cavity which contain them ; the perie:ir(liiim inlands in a 
aimilar relatimi to tbv heart; the pcritonenm lines the abtloniinal eavitv and 
olothi^ it4 emilaim'd viscera ; and the vaginal tunies perform a like service for the 
two chaniI)er.-« of the scrotum and the organs (the testicles) whteh tin- lodgtd in it. 
These serotw membnmes will be treated of in detjiil in connection with the organs 
to which they are res[)cotivoly related. 

2. The Lining Membrane of tlie Vascular System, 

This in the inleriilll eiwl of tin- ln-iirt and veKi^cU. knnwn also as the hmiea 
intima. It bears a close reseiublanee to the |>ro[«-r wroti* niemhnines in 
Btmctlire and appeamnee. It^i iiower of forming a tluid like that of the great 
serous saca is not to be doobtod, Init i.t not demonstrable, jls Ihe flnitl nin>t mingle 
with the current of bloixl or lymph as soon a* it is formed. One al all acquainted 
with the circumstanece favoring the coagulation of the blood, mid tiu- neeessityof 
liaviiig it flow freely through the microscopic tain's which wi- eiill ■.tipillaries, 
would fei-1 wurmiiteil in the declanition that no other menii>iitnc thiin .n Hi>nin?i 
would !x^ practicable iw a lining to the blood-vessels and lynijilialte.H, If n 
mneouK niembranu were empluyol for the purpose-, the small vessels would 




SYNOyjAh MKMUItAXES. 



69 



ipi>«(lilv h«H«me rlogg*d wiiii its thivk am! slliiiy st-cretion ; and the tliiniwM and 
nt d<'li«tte euiancuiH nM?iii)>r:ino n*ou]<l ol>V)oii§iy Ix? too iliick and L'iiarsi> ti> 
iTmil the tmii-'iidation iK>c-<-^.!<iry for ihc nutritiou of ihe tistiucs. Only a ktikis 
Emi-n>liraiit- wilh iw almost IriclionlcM surfaw uud its wau-ry secretion t-oukl jws- 
l&iblv Dieet (he retjuiivmi'iiti^ of tliv ra»o. 

The details of strwHiin- uf the Diiitvn iiilinin will lie iiro«rntcd in c<unDOction 
witJi thf dfScriptiiHi of i\\v hoiiH, liluixl-voJtM-li', un<l lympliatio, rcBpeclivcly. 

3. The Lioin^r Membrane of OertaJa Cavities in Snstentacnlar Tissaes. 

Th<- nnwi <'iiii-->|Hi'iiou^ illiL-itration of ihit form of wmiis mt-mhram- \k found 
Jn the iiitenitil rar. Around the greater part of the m^nibranotiH labyrinth, wliich 
Lk the i»*eultal j>oriion of the organ of lieariiiB, and lietween it auci the hone \a 
hvliti'-h it is lodgtxl, is a considerable spiicf, lined with i^rotis niembr»n«! and filled 
with n wnlery fluid, which in called iK.Tilym)>h. AixitlK-r i-xuniple is foinul WtU'cen 
tlie back of tl>e eyeball and the bctl of fat upon whioli it reposes. It is eutkil the 
capfule <if Tenon, and is a shut sac, wltli n visccnil layer ii|khi the globe <»f the 
eye and a parietal layer attached to the p«<tjnwnt adipu^- tissue. It ucrmils frw 
~ lovementH of the cvq in tiic orbit with the It-u."! puN>ih!e friction, in ehanvter 
fnnclion it cloHely rGseinhli-!< the proper ^roiis nivndironiM. 

4. The Lining Membrane of the Oavity of the Cerebro-spinal Axis. 

The brain and r-pinal con! are hollow nrgaiL-i, Their cavities are lined with n 
dt^limte menibnine, serous in churjeter, iiti epithelium iM'iiig in emiiryonic life 
Biliate<i, awl \U secretion ihin and waterv. The membrane Is known as the 
i/ynw ("(pirment") or c/mwfynMi, It will be described in the cliapter un the 
erehro-tjpinal Asi«. 



SYNOVIAL MEMBRANES. 

By certain atithoritiea the synovial monibranes (viemhrawr gyntmalfti) are 

clite^ol with ttw HerouE, and there are some gooi] ai^nments in lavor of lliiit axsa- 

liuiion. But, white these membranes have no communication wilh the surface, 

Ind have the wime order of function as the serous membranes, there are such 

diilireinTs a* to jii*tifv a s('|iin'ntion of the one from the other. The eroup of 

3yii')viid nieinbnines with which surgeons have rawt to do are not ahnt sacs, 

allboiigli «iich tbrnis u [iiirt of the wall of u closcil cavity ; tliey have a dlffcrrnt 

lining from wtrous nKMnhranc-!; their fcen'tion it not wimus; ami they a it- not 

ciutcd with the viscera. Thercfori-, tV-y hk \n-n- trejite<t by theni»clve;$. 

The syiKivial niemliran*'S frmn a part or the whole of the eucliK'nrc of certain 

ivities, which are a--«iicialed with the a-M-im* fiiuncwork or tiie niuscnlar sy>ti-ni, 

th ; and the service wiii<'h they n'lMler is ihe 

lication of jKirts whidi glide upon each other. 

A syniovial membrane is composed of libroiiA 

mci, having on its free surface an imperfect 

jovcring of o«'IU (Fig. 71), and thns affording the 

lilt i'Xfi']ition to the nilc that free surliicvs are 

iiinplclcly clothe) ivilh cilN. The«e eell- are of 

HI rt-LMilar »hai>)-, an- bnuuliid, ami are fr.tther'.-d 

Uii little ]uiti.'hi.-:s, wliicrli an- xi'alteii-d over the 

irtiioe, Icnviiig con.<iidc ruble an-iis u|Kin whieli no 

fllular stnwrtnre ap{iears. The nells niv ulVn 

ilk-<l i-piUii-liohl, which means '' like epitht-lium." 

Their .■iiwrction is a glairi' fluid, which ^tm-iirs 

He entire free surface oC the membrane, ami is 




rill. TL— ^nnvUl iiwmtirafli-^RM 
inrrfliM. Bliovttiv liuiTlW'l cuivrliii of 



lied »viw«'io, from its resemblance to the white of e^. 



70 



ELEMENTAUY TISSUES. 



Synovial mtnibniiif!* an- ilivkK-d iiit« tin- following groupet : 

1. Artw-uiiir. 

2. ViiK'""'- 

3. Bui>uil. 



TIk 



1. Articular Synovial Membranes. 

ic«f octiir in thtist' nrtiftilutiuns uf tlic botiy likcleton wherein two tmi 
move iiiKiii wu'li oilier. TIk- liomw i-oiiwnKtl in such a joint are coveRil on tl 

.Hiirfat^i^, wliioli untcr into the comixD^ition of] 
the nrtictiliirion, wild n cni^t of «irliliipt'. whose 
fni- ^nrtiii't' i:i vcrv Mnootti iind haixl, Tlit- Ixines 
an' held I'ljriiher hy Ktmiiff Imitdr^ of white 
liiirouw lin.-iif — \\w lifpmicnts— wliiih oiK^jiftU- 
latcr tlip ex[wrulcd rmls of tin- ItoiK'.*, forming 
hollow cylinders, which iHitind iht* joinl. Thi- 
inner Kurfncc of a cajisnlar lipamciti is eovcrnl 
with a Piiiovial nH-nil>miic. which i^ n-tli-ctcil 
from it II little way npoii llic mavjiin of cjidi of 
the cjirtiliifies. Thus, the i*ynov!id nienil)raii<' 
is a short tiiU- with its t-dges turned inward. 
Tlic II rning(nit-nt of the pert* will be seen loH 
Fijr. 72. ^ 

II, IIS sonictimi'S ocoiiTv, n liftimicnt or a 
ton<lon j)!i!«>es Hcnw!" or (hriHigh the juint-cav- 
ity, till' !>yniivial niertilminc <-iiKheii(h> it. Oo 
casionnlly tho monihraih' exhibits fohU, which 
Fni.72-iiiaf«in nr»riipuii.rfji.OTi«i <•">«« the oavitv or hang into it liki> liingci*, 

r'.rn:^;rn,jM'"(:,r".ii;^';vV';,f'?s,r»'' «"*! v^'^^h^^ ---^"taiii some adiiws.- ti.-yiic. in 

Tilt; ii)iioYJtii iui;iiiiimi]c u. siiuyiu It ■ all cases the sviiovin stM-retod Itv tlii> mcmhnirie 
lirokon line. (K,H.(..| i i ■ . .i * .i i ',i . . 

luoncatcs tJio carllIagc^ iind other struct i ires, 

which present a free surface in tlie joint. 




2. Vaginal Synovial Membranes. 

These are *o named from vut/imi, " n shi-ntli,'' mid .-iiv ali-o known ai* »i/niiri'il 
aheathn. They are found in i-itnationn where thi; tendons of niiisrh-s run over 
bones, to wliich they are bound down by stntiip, fibrou.s bandit. The Ihhic in tjicwe 
cusi« is grooved, and the fibrous titteue bridges over the gutter, thus iiiakiitg a 




Ph., M,— lljuiimm .if a vai.-<ii>l 
niKivln] mf^iliniiaii irii-ni]>3>-»<'-U-]ii. 
llkf 1nl>I^^^l^e In tjiown I^T Uiv 
tao\n\ Unet. .\ «|«ci> li Ita bo- 
Ivfi-n ilif li'ixlnii iixl i'b*iini'l'W'>)l 
lUt Ihr ii»kr ip( il'inrnr™. >y. HO.) 



Vjti. T4 [iiHeniiK uf ■ vMiiuil niiavial laviiibraiiD In iQnsltiidtDa] 

HCliun, Coinparv Willi Klg. 7*. [K. U. ti.) 



verv Btroiig. fibi\j-<>»seous eiinul, ihroiigli which n trndon passes to Its destination. 
The synovial membrane i» arranged iii the form of a tubnlnr sheath, one portion 
lining the canal, the other invcting the enclosed tendon, as will be seen in Fig*. 
73 und 74. 



MVCOVS MEXBRAXE& 



71 



In llir- niDvvmpnbi of lite tcnduii friction is rc(luix>«l to itfi lowest teirna bv the 
lubriiiitiii^ afp-itrv nf iIh' NVtuivin. 



nMT4t 

trNvH)' 



'_y^ITHlWIB«. XWHI 



3. Bursal Synovial Membranes. 

Oihcr iiatucH for i\k»v slnicluro! 
are ^norMi/ Ahtmc (" i*yiK>vi»l puix!*"), 
hm-tur mncnto! ("iniiwuw [mrsiC;* "), «inl 
vmieutar nxfnnruil mi-mlinnirn. \ ^vno- 
viiil liiint:i U II littli- liii)! iif tlliivaii^ tJM- 
i>ii(', liiKtl wiilt ^yiioviiil iiu-iiil)i':iiic, ittid 
|ila<i-4l iH'twwn |K»rr!» wliicli nuivi- ii|iiiii 
«!acli itlhcr, iiA twn niiisclt^s, two 1<tn(lonn, 
I a muitcl*^ or it-nHon iiml a bon«, tlie t^iii 
and ;i bone. The i&c b* <?oni«'oted witli 
fuiToimding (KirU bv art'oUir ti(*wiie, ami 
tlic 'ipiKiHtt' sides- of itf inicnml f^urfaoe 
an- ill t-otitiicl, nnd kept moist with ny- 
uovtu. &>nic of llicM ini.'mbnin«< are 
<lvvclo|)ed from »[Ktoi-« of areolar ti&^iic 
by cbwiin' of (.•omwclioii with ^finrroiind- 
iii^ ^IKiitii, iiihI i-omli-rLvtliiiii <if tin; coii- 
liguiitiH tiiMni'uli of ibc fi-->-->m-. 

MacOnS MEMBRANES. 

T)ic MTMi^ and tivnoviiil inetnbranes 
Heir ctoMi) MKMt ; tlic niucoui> metiibniiK's 
{utrH^trnn'r mxcfwitr) line pa!*«igcrt and 
cavilii-?i which luive a direel oimniiini- 
nilton with the outer Mirfaee of the bo<!y. 
IiiiUh^I, from the |diyxiolo|;ieiil point oS 
view, tlio iKirlN whieli aiY- covi-rvd by 
tlwm are vxliTnal, for ihi-yiire rcpirded 
ai invPTMionH of the inte|riii(n-nl— jior- 
lion.- of the outer i nvc.it nii-ii I tmked in 
and mot)ili>-d, but nev(?r lacking lonti- 
■uity with iu 

Theix; arc two separate nets of miipout* 
niMnbranes — (he gastro-pnlmonary and 
tbe }^>nilo-nriimr%'. Eaeh of thewc eon- 
-lints of 11 continuous membrane, which 
liih--» two writw of ont»M>. anil vario* in 
many n-jifwi-l!^ aeconliiij; to the orgsm of 
wliu'h it fi>rni* u |Kjrt. The iioMro-jiul- 
momu-jf MiuMBiM utrm/ii-fitir (Fip. 7.^) fnr- 
oisliC!ia freif tmrfiioc for the iilinientiiry 
and n^pimtory syMrm^, unci p-t^ it» 
nam;- tmm a principal oipin of ciu-li — 

ilbi' T<toniach and the tun^. The «//- 
vu-nlaiy imrl of it lM?;^tn'< at the lips and 
[ta-vu-s tlimn^b the month, the middle 

,aii(l lowef^l piirts of ifie pharj-nx, the 
jllllct, etoninch, r-mall and larj^ inteH- 

^tini-», and anal canal, and then cornea 

lu the r<l<in-.snHii(v. In its courve it 

eiiib' offtwt* to ihednrlK of the «divai^ 




iTtt'- 



VHUM* 

•IHUk 

COVITIU 
■UtlMHtU lul 




FlQ. T&— DlMcnni ot Ibc )ta*tnyptilinc>nanr muwn 
mniiibnii*. iiliiiwhijj thu ouutinulljt ■>( tU lb pitUi. 



72 



ELEMENTARY TISSUES. 



glands, of the pancreas, and of the liver, to the gall-bladder, and to the vermiform 
appendix. The respiratory portion begins in the nostrils, and passes through the- 
entire pharynx, the larynx, trachea, bronchi, and bronchial tubes, ending m the 
air-vesicles of the lungs. From the nasal cavities it gives prolongations to the 
inner surfaces uf the eyelids and the front of the eyeballs, and to the chambers in 
the frontal, ethmoid, sphenoid, and upper-jaw bones ; and from the pharynx it runs 
through tubes to the drums of the ears and the cavities of the mastoid portion 
of the temporal bones. The genito-urinary vaieous membrane lines the genital and 
urinaiT tnicta, as its name implies. The portion which forms a part of the male- 
reproductive organs (Fig. 76) leaves its junction with the skin at the distal open- 




DUCTS 
OF TtATta 



no. M,— DlBgrara of male genlW-uriDary mucous mcmhrane, ihowlng conlinulty of bII ita pann. (F. H. G.l 

ing of the penis, and is traced through the uri'thra to williin an ineh of its proximal 
end, where it enters the male womb and switches off on each side into tlie ej.icu- 
latory duct, from which it sends one prolongation to the seminal vesicle iiiid a 
second to the vas deferens, and through this last runs to the epididymis and the 
ducts of the testicle. It spiids ofi'scts t() the ducts of the stiliurethnU glands and 
to those of the prostate. In the female the mucosa of the genital tnict (Fig. 77) 
begins at the vulva, goes through the vaginii, the uterus, and the two Falloiuan 
tubes, at the free cNtremities of which it is continuous with the scrons membrane 
lining the abdominal cavity. Offsets fnini it line the duets of the vulvo-vnginal 
glands. In both sexes the vrinayi/ iiiiirov^t Mcnitu-atir lines the urethra, bladder, 
and ureters, ending at the piipillic uf the kidney. 

The variations in the eharactcr of the mucous mcmbninc in diltcreut |>!irts are 
very grcjit, and changes arc extremely abrupt at several }iiiints, while iii other 
cases the nuxlifications are eficetcd very gradually. The roriiuii (Fig. 79) is gen- 
erally much thicker than in serous and synovial membranes. It contains a com- 
paralivelv small |)ro|(ortiou of yellow fibrous tissue. AVhcn it is largely oe<'iipicd 
by follienlar glands, the ordinary libriuis tissue is to a cousidersible extent rc|ilaccd. 



MUCOUS IfEMBRAAES. 



73 



hy aJf !!<«<!- IV I Wilnr, in whose moslirfi aiw cnliiii<;Ii'il lymplioid ci^ll*, thiis oonsti- 
liilin^ a ilitfii^ lt-mp)uili« tissue. L'Miiilly tlir i-i>riutii i.« lH>iiitil<Hl toward the free 
surface by n bawmcnt mi-mbnino, iiitil (iix-|ily \>y a ihiii laypr of plain muscular 
tieauc, which i» nunicd mtucularui niiicuhc (" the niuaouhtr [ooatj of the miicotis 




VULVA 
no.?!;— DIWTiiB(>rftnwkK«Dtlo4irlii«t]r inucoiwraviubMnu.ibHiilnBixaiilBultraraUK«f)U«. (P.H.n.) 

[nn-inliranej "). The rpUhe/ium ha the one olcmpnt in the nM-mbraiw which is 
never wantinR ; bnl there are only !i few ai«'-s ami very limitdl arciis in wliieh it 
L» ibe sole npre^'enljilive, tlie covering ttf the eoniia being lli« most (■on.spieiiuiiTi. 







COIIIUU 




rt-: ;&— I»ii4tn(ii] I't muiMiia iiiii'iiilirAiiv In rtrtlcdJ fcMlcn. (P. H, O.] 

Thi* epithelium may bi- «iiit:Ie or jilmtified. of any possible bhape, and with or 
widtoiit c'ilia. The nienibmne di-rivi's it^ niiinc from the jjlairy fluid, rmieu«, 
wtiic-h always covers it. This sccrptirtn b> protwdivc, uihI w ubntidant in proper- 



74 



ELEMENTARY TISSUES. 



tion to tho amount of irritiilion to which tJie iniinltmnv is »ubj«!trd. Where Itw 
vjiithcliii) rmil is oohiiiiimr and winj^le, the tiiiicii.'' i^ t'linii.slnd viry Iiirply liy \]w 
gnblct-colU III' llie ejiilhelium ; bin, as itiow t'hiiliiies aw a iiiodilicutinn i)t' i-<>liini- 
nar cmjIIs, Uiey aie not found where th« epithelium iw flat ; and in such i^w^ nil of 
the mtieijs comes from distinct gliinds, which devote themselves Ui this wurk. 

Mueouii membraue if (icnemlly eoniieeted with finbjjieeiit parts by areolar tis- 
sue ; but exccpliitnully thi'^ is not prewnt, and then the membrane is nttaehed 
diriftly. This ixt-un^ only in caw.'« wlieri- tbf pa^snge or cavity which the mem- 
brane lino* is not subjei't to ilistonlion. as in tlir iihh:. where the corium is fiistened 
to the bone. In ^enenil, tin? unjolnr layer beneulli iiiucoii» meuibrnDe is very 
abutiilnnl, and the n.-nrfiilne** of this arranp-ment appcarp when we coni-ider that 
the eoriiini hiis but little claMip tiivin«> in itn i:om|Misition, iiml in many easc^ is 
IHTvaded by frhmdnhir slructnrcs, wliieh wonhl be injured by i!ii- stri'liliirij; of 
(he membrme. As a rnle, the eavilios and tiibcA nhiih nn- limd with niiieouif 
inembmnc are liable to great ehanges of !>i/e, owing lo their intiTmitlent cm-c npji- 
lion by solids and fluids lo sueh an extent as (o distend them. Between the 
|KTio<ls of db'tenlion are tiine^ of collapse. If the membrane were elaslJe, like 
(ierouii menibrane, and ha<] no delicate glands enib(>dde<l in itn .iul»tai]eo, it could 
be stretched within a Inr^re range without harm, and would return to its state of 
relaxation on removal of the distorting foivc ; and in such ciivumstanees it would 
nt*d but a moderate areolar layer between it iind the subjacent parts. As it is, 
the metnbRLue when relaxed beeonics nion; or lees folded — thrown into shallow or 
d«'p wrinkles — and present** a BcricB of ridgei'> ealled rrigo', which lu tubes are 
arninged in line with the lungitudintd 
axis of the orgim (Kig. 79). When a 





Fic. 79.— niiMtntm 'liowliifr ihe Ailillne or thp 
lnQi>QUft m^mbniii? in n ^nllaieod tube. ^\ II. G.) 



I 



I 



^t, Kl— Ulnimni aliiivitiii tlio efhmDent of Uie 
rilfti of mncoQi mombrnnc mid Uic octm|>ro»1on of Ihc 
BFiMiUt UjCF U'lii^n tliv lulw if illiteiiilisl. Coniffn: witli 

Fig- WO, (K u. It.) 



dietending fon-e \» applied, ii:< in the [uii^Aage of a bolus of footi through the gullet, 
or al\er a Itirge diiuicr has been deiHisileil in the stimiaeh, ihese tbids ar<- elliietKl, 
the nienibrjine beeoincw smoothed out, and presents an even siirlinv (Kig. 80). 
This extensive ehanj^ is rendered jxissible by tlie ahundaiKe of the nubniueous 
arecilar eoat, which is strong and elastic. 

Miieoiis menibrane is very vascular, the vessels for its supply running in the 
snbmneons areolar tissue, and sending minute branches into the corinm almve. 
lis nerve-sun|ily varies givativ in different parts — some being esin-mely sensi- 
tive, others <iidl of feeling. As would be inferred from the amount of lymphoid 
tissue in the coriimi, its lymphatics arc very abundant. The peculiarities of the 
mucous membmne of iwch part where it exists will be detailea in the d<>eription 
of the oi^ns n-sjx'Ctivoly coutrcrned. 

CUTANEOUS MEMBRANE. 

Tiy this term is indirateil the iiiembnme which furnishes the outer covering 
of the body, and is unlinarily calb'd i>kin. It is a complex structure, and liiu 




GLANDS. 



75 



a vsriety of ftinctions, amon^ whi<-h \>^ the (Imtin^iiI^'Iiing of imprcsiioDr^ of 
toucti. It will, thcrufuK, be more up[in>priiitc'ly cuiD^idiTcd with itie orgaui- of 
tlie sensM. 

GLANDS. 

A glninl is An oi^n, which alicttracte from tbo blood eortain niattriaU »iid 
tnjkk<4 of ihpm a oew wibstanoc. ivliich U tliea <iiscliar(^l iiilo a cavity or upon a 
jttirfuw. In other woitls, a gland is a wcreting organ, itj; procesj' and its pri«liK;t 
Ixtth bearing the tiatiie of !;ecrL'ti<>n. Simply cutK^trutricd tiK'ii]brat)e!<, such as the 
serou.i, doiiblIc«i jwrform Mjnie st-crctori' work ; htit it is always of a low onk*r, 
and the re^iilliii^ pixxluct is only slightly difTcrvnt from llic niatcrials of which U 
is composed. It would iiot be cxpcctt'ii tliut thi- wlls ujion it plane siirtiwc, whose 
priiKripal function is pixrtcctivv. iin<l which urn- oon.Titantly siilijcclt-d lo hard u^sagc 
4>D ai'cnunt of their r\|.HM<.'d Mliialioii, woiihl be able to ilo i^i'iTi'lurv worli iif atiy 
bill the muvi primitive kind. It would be a^ rea.ioniilih' to deniuod a Iii^^li j^r.uiv 
•>f work fnim an ,irti*;tii .''ttttionod in the middle nf a tboroujtitiiiire, where he would 
bejoslUil by vvery |>:i.v>er, Suchaone nee<).4 freedom from inlerfuri-iUH-.and with- 
dnwri frimi the b(L<tU! of the throng into a Hccludcd retreat, when- be ba* every 
fai-ility for doiuji; the mo(*l deli«ito and elalwrate ta.'UtX Nature aoU in preoij>ely 
tliL" way in win.- tr mutiny an orjran which \^ to make a secretion : a depn-ssion 
appears in a mi'mhrane — an inversion td' the surface-- tructure takes phitM- — and 
tliP cells, which :iri' thus removed from the worries and danj^rs of the uiion and 
exposed locality, experience various changes. Thcv bwimc phnnper ;nul sottcr, 
their nuclei enlarge, and thry develop a capacity for secretion, which their lest) 
fiivorably environed ncighl)ors ncvvr vmuhite. The niat^'riaU which ihcy abstmct 
from the bhxMl nnr jio wrought over (hat their oripuiil clmnMrlcr is not sng- 
g^wlcil by liie niituiv of the wercliou of which they an- ihi' infrredienl'<. The 
or;:!!!! which accomplishes this thing is a true gland ; an<l, tw a nilc, the more 
ctiraplcii'ly tl U gnanh-tl from annt)yuHci- and interrupt lorn', the more clalK>ratc 
and vuhiabic i» it" work. 

The CK*«;nli»l tiling in a glaud, as hji» already Ik-cii intimated, it* the fjntkeliat 
erf/. The forms of wfreting n-lli> an- as vurie<l as [Hmsible, but the londenev in 
to kircp near the spheriivil type. Indeed, .'•pberoiilal epithelium is hardly to \te 
liHiked for outside of ^'Lmds. 

The simplest torin of n j^land h the follieutar, a mere dimple in the surface 
(Fig. 81, A). Eniargtmieiit of the embedded liil)e, without dilatation of its open- 

A D >: 




^"Swk 




' -nuB ibowlna il'i't'lnpnivnl nf i:tnni1>i- .1. ■ motr dimple In the >ur(lice^ B. cnlarcrtimil hy 
rnmcnt bv dllnUiLr.n, li. neiniLlilnniliin •■! K aiiil (.'; K » nreaumi k1»ih1^ F, iliivi-lhiiiiiniit 
, . a. n tlnth >u>A- luiiii*j[,'l] I'nll.nl. (F. II. C... 

ing, niakejt a saoctdar or fla.-<k-H|ia|H'd gland (Fig. 81, C). Branching of ibi' lower 
parts cliai^ies a .-iinplc ^lati<l into a com]»ouml (Fig. 81, li), and what was pr«- 
vioasjy (he iip)>cr part of the seci-eting organ now be(«me>' lite duct of ilic- 
«Iiai^, its epithelium losing its true glanduUr character, and heertniing mon> 
like that n]»<in the general surface. By repetition of llu'rw- prooesises the 
gland liet-omes not only hirger, but more complicated — lihrous or reticular 
tissue ucvHpie# the intor>«ticc:<:, and airf>rds mechanical support; muBcular 



76 



ELEMEXTARY TISSUES. 



tu»u« fijrnu'i amunil the duct» ; and iu nianv wa^ elaboration goes nn, iintiri 

in sonic i^lantlK not a suggestion (»f the orii;- 1 
iniil type n'miiins to oiii^iial oltscrvation. An<] 
y*'t, lln' iiurtnliifiL- of tlio niosi intrk-att'ly con- 
jitnictwl jjland I'un be tniftd back to tlie 
)itlle invonnion of tin- *nrfaw. wlikJi h»K 
been ulinwn to Iw n F<im[)li> follii-iil.ir cliind, 
end tb<- .ttnicttiml pnn('i]>l<.- i.s idcnilMil 
th« two. 





nn. n.~CcaLu>uuil tubuUr Kinud. Tht! 
UPDM Mtt I* Uii> (fuel : tlie lown u Uw Mrrcl- 
bw portion. (XAlllkar,) 



Fill. sa^cnmiKiund racrmiMc slanil. Thi' rwH-iiiIilaDc* 
10 ft buncli of (Tult Ii very in>rk«4. IHIlne-EdwardaJ 



EMBRYOLOGY. 



BV J. P. McMURRICH. 



At OOP period i)f iu exif-tt'iiw every AertHmitc imiiuiil U rf]>rc-*"'nto<I by a t<ingV 
J\. coll, from which the adult individiutl lU-vcKijw by iijs rv|"-iiU-ii ilivi^ion Oiti 
by the functional and )u£tolu)>:iail diflerentialidn of \\iv ajyfPt'gatf i>f pcll* so 
ft»nnc<l. The cell, Imwever, wliieh hiw ihc novo'.T of iind<-r^iii^ lhip> develnpnipnt 
b) one which result;^ from the eon)|ih'to fusion of two diMinrt elements, likewi.^e 
ccilx, ime of which is tcrtiK-il iW riium, and rejire-wots the female element of 
n-prudiHiioii, iIk' other heiiig tlio xfteifnatozoon, tlic male element. 

SpermatogenesU. 

Thfl male c<'II le formed in the If.'tiw, and, if h section of a seminiferoue tubule 
be eJianiiuiHl, an a rniii cement will be seen whi<^li is represented diagramafically in 
Fig. }^. Tlic w\U liiiii)j>: v&vh tubule are arranged in several hiyers, the outermost 





Plo. Hi— Dcvvlc'iiniKiit of ii|iKnn&IOK«. 

layer bein^ formed principally hv n nundx-r of cells known a.'< »/« 
Each of thcrie from lime to lime divide:*, ouc of the wlls mi prodiiird {>onitstiDgf1 
aa a B|icrmaI»«oiic, while the other beeomes what is termed a jirimnrif itfirrmulo- 
rytr. This ctll later divitlea into two cells, each of which is a Kecoiulnry upenna- 
£o<-y«, aud these, andci^ingafurtherdivision, jpverise to cells termed xpfrmatida. 
Thus, from each primary spormjitocyte, by two divisions, foitr spennatids are 
d«-Vflo]ietl. and i-adi of thee last becomes a tperTMitozo'&n. In addilitni to ihese 
varimis «■!!■<, oth<-r> nn- U> be flniiid rci-titiK "jum the bii'^ement membrane of the 
nibulc, and vxleiiilin^ tlirou^ti llic various layer* of the developing eelln, the 
^pcrmaloxoa beinj: )iroii|>iil ti;>oti their inner enilj<. These an- the Sertiili etlh, or 
»uppor1mg ceiU, and they do not take any part in the fomiutioQ of the spemuito- 



78 



KitmiYOLOGY. 



CELLS OF 



— r0NA «AO<«TA. 



ucLitua. 

<0 TALN. 



zoa, but, as iheir nanif in«ii«Hes, serve for the support of the germ-celle, and 
jtrolmbly awist in their nutrition. 

The sjiermatozoa iiro the rchiill nf niodiliciirion of the isperniatitl". Kat'h of 
tliese tutier in at fir;;! a rotiml (■'■ll willi a rather large nnt'lcns. near which lies the 
tvnlroAomc. (iraiiimlly this cell iliniirat'^. tlie nuck'Hi- takes; up st piisitioii iiwir 
one extremity, ini axial lilantcnl ilcvelops in the eell-lnMly. the eeiitrotM^nie comes 
to lie behind tho iiiieleiw, na<I, a« the lin»l rcjailf, there 'm^ pnxhiwit the nuiiiire 
sperTniito/tH>Ti, a h<i<iy tiicii.-uriii(^ in h'n^h about j;ln ineh, and eonnistinfr of (ii) n 
pyrif'irm hiuid i-Diiipiwi'd uf iho nneleuH of tlie original npeniiatid, -lurronndfd by 
an (ixcff-dingly thin layer of prutoplaHni ; (A) of a " middle piwe," immediately 
bt^himl the head, and repn-wenting prolialily the eeutrosonie ot the spemiatiii ; (r) 
of the tail, derivetl from the eell-hodv of the (i|jerniatid, and eom|»osed of an axial 
filament stirriinude^l by a i-heath uf protoplasm, <tome\vhat variable in form, thotigh 
usually simply eytindrieal; and{<0»f a terminal filament, whieh is the end portion 
of the axial filnment. 

Ocigenesis. 

The ovum, ai* il vxist^i in the ovary, i-orre-ijKimi-* lo the primary .^iienuutoeyte 
of llie mnlo, finil must luidergo certain eliimgew eii- it in ready for union with the 
spermatozoon.' When n^ady to hurst from the Graafian folliele, the human orum 

(Fig. S6) is a spherieal ecll about 
j+js ineh in diameter, enclo-ed 
within a membrane, the tona 
imliaUi. and containing a laiye 
jiiic/fut>, i-ituated HUnewhal exeen- 
trically, ivhile centridly there arc 
n nnniher of gniniih'.'- •)f fiinil- 
ti'illc, a Hnb^lunec nuirli more 
ulaindant in ihe ovn of other 
niamiruilF', -■•uih a» the eat. ami 
wliieh form:- llii' greater mass of 
the ovnni i>f birds and reptiles. 
The nmtnrntion pbeuonu-na (Fig. 
86) by a rjerie.-« of divi^iion.-t eon- 
vert, the ovum into .s struetniv 
honioliigouw with a -ptniialid. 
vVt the first division {A, B, O the oocyte, as the ovum at thic stage may be termed, 
divides into two eells. one of which is, however, very small and is termed a poltir 
yfutmle, while the other h pnicticiilly a*i large as the original oocyte. By ii second 
division {/>, E) n second ]iolar globule Is formeil, and ihe iiueletis then passes into 
the resting slagi' and miiivi'.-^ toward the eentix- of the ovnm (F). There are thus 
two lualunilion divisions, ju^l a* ihciv uix^ Iwo divisions uf Ihe sperniatwvtes in 
s|K-rm!ito;rene-is : and the polar gli.bnles are to be ivgaiiled a.i abortive ova, whieh 
take no funher part in ilevehipnifnl, but dt^-nerate. 

After the extrusion of the jmhir globules the ovum is ready for union with tin- 
spermato^ioon — a pnteess which tvcurs ])robably, as a rule, in the upper [wirt of 
the Fallopian IuIh*. A spenuatowMm |>cuetrating the zona radiata is rect-ived inti> 
the substance of the ovum, and gradually passes eentridly toward the ovum-nii- 
ileiis. The lail of the s|H'rmatozoon is stioner or later absorbid ; but the head — 
"hiih. it will Ih- rcmemlK'red, represents the nneleiis of the s|H'nnalid — ami the 
middle piece |iils.h on lo come inti) ehisc up|>iwittou, and finally to fuse, with the 
ovum-nucleus, llie oimponnd nucleus >hi pmihieed soon becoming eonverte<l into 
a division spindle which inangiimtes ihe segmentation of the ovum. 

' Ni-illiPT thtwp clmnB™ nor ihe pliPiimiiciin of firrtilizaliun have vrt been obwrrrJ in llir Imninn 
DTum. They linve lnvn id»crvml. Imuiivvr, r<.'|>i.-iii>4ily In (ho (fra of niiui}' of (liv luwvr miiniiiln, tvth 
TcrUlinui- Mid iiivcni'brHlf, hiiiI ilivit i^Fiicnil riiniilnrilv in all cbms fnabw lliv jiroUtbilit}' thnt llicjr 
oeoor kbu iii tlitr Immiui uvum nltuoit a Roruintf. 



I 




FlU. iBh-Orani. iWaldvjrvr) 



L- _ _ 



Till: EARI.y .srA(!E.S OF DEVKLOt'ilEXT. 



7» 



It wiiutii Mf-ni fmii) ih<-Hi- |ilM-itomoiiii t!ml tin- cxx'titiitl tiiitun- of fcHilientittii 
U tlip uriioii of \ht' iiii4-tci of tun oi-IU, (Ix- nniall amount nf )iriit(i[>la.->m pn-M>nt 
iu thi* lii-a'I >>f ilir sjMTiiuHozt>('ni mtmiii^ to |ilav little |iart in tin- pnnitss. ^imik* 
botli pati.-riiiil iiixl niii(i>mal c'liarHi-tunr-iicn ma;t' m- iiilitrritix). it liiifi lieen !iiiip|M)e4td 




oiaaiirif At 




rOLAH OUIBULC 







ariHDLC, 




•ICORO >OI>n 




D B f 

Fii!. W.— Dtwirein llluatntlnv ihtr phmninttna ot nialiinilnn. (TMtui.l 

ilinl the nuclei must !»«• the mntr'iniil tx-nrors of heredity : iind, wnoe tW rlinnM>- 
titi]4tr Aiil>Htanc« of ii niiHoii!< i^ l)ic r-liroitmliii, tliiw lm!< iHt-n n-^^irtliHl liv niatiy 
mithor>^ a.* tlir nrltial Miil)Ht»iKi> ciiiifcnifd in traiii^tnitliii{^ iiilK-riU'd |Ki-iilinriti«ft 
from tliv |NiiX!iii U> lliv iitrT>|)riiig. 

The Early Stages of Development. 

Bv wpmentation ic nimnt il»- .ftuvt-rsion of tlie lutii-elliilar ovhiii into a ra&m 
ofwrtji. n proc«»» whifih results from a series of division!*. The ovum first diviiU^ 
(V\. 87) iDlo two CM-'IU (a), each of tJii>Be again dividing, so that four oclla are 







Fin. B7.— SfBBHriiloliiJ!! (.f the omni. i After lan BdicJcn.) 

fomipd (h), and, (he divitiinns omtinninjr (<; 'Oi » solid mass of rellfl, termed a 
miintin, !«= prodnittl (i-). A wvlion through siioh a mass (Fig. H8, .1) will show 
that it is cum[KMed of an oiilor layer of somenliat flattened cellH enclosing a 



ydk 



80 



EifiiKYOLoay. 



number ofdUtinctly gnmuSur ccll^. At fin-t no cavity existe in the otutre of Uh 
ni«ni1a. but i^ooii the outt-r wlU bf(.'iniii' in largv purl forced away from the innc 
oiic^ by ibv iinbibitioji nf u diii<] siipplietl by tlic yuaWv of the uterus, and what is 




•COMCHTI- 

TI«M OAVITV, 



lernit'd » nrffitu-j^ation-cavUy is formed (Fig. *?S, i;). The muriilii iii thus cii 
vprtvd into a iiollow vesicU', termed the cml/rumiii: t'fwV/f, whose wall h coinjiDM^I 

of n single Isiyor of ncIU, excejii til 
■cLiuctD* on*' n-gion, wlicre what were die 
inner <vlN of ilic uKinila form a 
lenticular ihirkcnin}; I Fig. ^IH). 

i.ufiT, till' i tuit'nii«.->t cell-* of 
thi* thiekeriiiig U'lnmc somewhat 
(hilteni'il and arrange thiinwelves in 
a ilij-tinil layer, wliieh extends out 
ill all ilireetions and event tidily oom- 
pli-li'ly eiu'Iiisi--* the segment a tion- 
I'jivily, which now is known as the 
j/iitk-Mio, or umhilicat reticle, tlie 
layer i>f w-I1h enclosiup it being 
termed the emloderm tFig. StO, A). 
While ihiK proeeMi \» taking place a 
cavity, known a» the avinwilv rtiriti/, 
nmke.i its apnearanee in the outer 
part of the rentieiiliir thickening, 
and the cellx which form the floor 
of ihc cavity beei>nic eohnnnnr aurl constitute a layer termed the rclmlmn, while 
the wlU between this ami the endixU-rm remain irregular in Hha]>e and fonn Uie 
met'iiirnn ( Kip, 90. A). T1k-«' thn>c layers are known as tlic (/cnft-lni/ryi', and it is 
by the difVercntiation of ilicir civile that the various tissues and organ.-" of the em- 
bryo are develoix-d, each layer giving rise to certain ileliuite ctnietun-M. To ihe 
jM>rtioni4 of the germ-lavers which lie in tin- floor of the iimniotic cavity ilie term 
tmbryonie dittc is applied, since it is from this i«)rlion alone that the embryo projjer 
will form, the remainder of the embryonic vcMcIe giving rise lo accessory struct- 
ures neceswrj- during embryonic and fleta! life, but liiscardwl at birth. 

The outer layer of cells which fonns tlie wall of Ilie embryonic vesicle has, in 
tlie meantime, increased in thickness ; its inner cells, which are continuous at the 
edges of the embryonic di*c with the embryonic mesoderm, may be rcg«rde<] as 
f<)rming the extni-cmbrvoiiic p«>rlinn of that lavcr. Tliis mesoderm now splits 
[landlcl with the s«rfa«'e of the vc.'"iclc into two layers, one of which, the tutnafn- 
jtlfure, adheii'H to the wall of the venii'le, while tlie otlier, the tplatuJinojtffHn; i.« 
more elosely a.^sociated with the endoderm (Fig. 90, B). The narrow deft between 
ihwi^ two inesodermie layers rapidly inereii«c« in nixc with the grriwth of the 
vesicle, and becomes an extensive cavity known as the extru-ciuhn'onic bodif 




Flu. W.— Kmlirrnnic vaiir't«. (AA^r van Bfneiten.) 



TUB EARLY STAGES OF DEVELOPMENT. 



61 



enrUif, or twtoin, inlo which tliore projects the _volk--Jip, onclosi'i) witliin llio t-mlo- 
dvrai anil f planvlinuplfiirp, ami iiiiilr<l to thv wull nl' iln: vvsiclv liv a injias of ni(.xi- 




■■HIOTKUHnV 






tiuucxfioruuM 




Pwi, tt>._l>la(ruBt nf frclioni thmiiirh thv huntrtn <iDbr70iilo vNlcltf In MTlj !(•<*•■ Tbe *clfid#rni It white, 
MMndcrm yvIkn.Aud I'liduilfnn blncli. 

ilerm to which the smniotio cavity anj embn-onic dipc aro imbedded (Fi([. !)l).' 

fn PiKTJ.'pding KtHgfS of dfvclopnicnt the embn'onic diw; and with it tho 
smniuliti t.-uvily viitiirgv^ thu giuwth W-iiig largely Id the dirccttuii in which the 



(wwcawnuu 







Pw. n.— ntaiiMiD r4 ict'tloii Ihroiiit)) Uic portlna of an early huiriaii Drabtjonic vnicle wliicli ri>ntaii» tl>* 
•nbrrn. |Att*rUnf Hpoc.) 

hffld fiid "f llic cml)ryo wlli inter develop. The [wrtioii of tlie iiies'Kicrtn which 
li<--.i U-hiiid tlie niimiotic cjivtty and cnibrj'oiiiir disc reniainii aeeuriiinjjly niinltenH), 
anil increasing in thioknixs mid length furiiis a iHtliele, tJie hrllii-nUilk, united to the 
nnbrvo ii«ir its hind cud, :itkI ntlachinj; it to the inner niiHUci' of rhc cmhryonio 
vesrcU (Fig, Htt). Immctiiatelv in front of it on ihc cnibryonie <li>c a darii line 
cxifixl^ -iome dir^taiieo forwni-H; it is formed by the fiiflion in tluM i-egion of the 
ihrw gerni-laypr^, and >b termed the pi-imitivf xtrfak (Fij;. it'i). From its anterior 
end a narrow band of cells prows forward, dicidaeinj^ the original endoderm along 
the median litK of the embryonic disc, and forming wliat is termed the ehnrda 
emioderm. Up to this (itiigc, however, there has been no indication of a diffcrcn- 
liation of ch-fimte oriinn*; bnt now iv proove apjwarn in Ihc median line of the 
iMubr>Mnie ili«;, exii'iidiiiu fn.ini the uiitcrior end vf thi' primitive !?lrcai< iilmost 
In llie fnjiil wtfp" of the dtie, and later the ccto<lcrm on eillier niilc and in fiimt 
■if the gnM>ve rijies up to form ridjres or fold*, wliieli eneluM" ihe gi-oovc and art! 
known iLS tlio me<Inllary fohU, the groove it*'lf Ix-ing lerm«l the mnhtllari/ yiitnifc 
(Fig. 1t'i>, the two together (iinning the iir!«t indication.* of the ncn.'oiis system, 
Immcdiaiely beneath the nn-dnllary gnnive another groove appears in the chorda 
endoderm, the convexity of ilie groove Iwing direeletl toward the floor oi the 

' HiB U imotifatly the ihnp<! whicli tlir ciirlinl liiimaii «nil>rTO al iiraaciil known haa mic)i«L 
II it i-vidmt, iliorcforf. that tlie vnriou" jmxfMM ili'wrihril oliovf aio hTpolhclicnl an far an their 
■l-lUifslimi tit ibiT liEimun mritirvr^ ih t'ixutrriii.vl, ifi^iiifh \\w\ iirv kni'twif |j> ficeur In tlio '^va of i^thar 
nianinials. It oi.ty alau Iv iioU'il llinl ()ip nn'^trDl gi>rti nlxiTc ilini-o niHlvrially fr»ni llist r«iinij at 
procnl m rmtirt-oluiriial tuxl- books. Iiui liic iinicturc of tnrly liuuion ova rccvatly cludicd h-ciuii lo 
dtnunil •amit aiich pninoua prot'oo*" n* ilfWcrltKHl. 



83 



BMBItyOLOGY. 



itillary frrome; itti lips later unite, the ravlty of tlu' touiiI wj formoil bccuinesj 
nlilitcrafiil, ami » solid v<A, the noiofhrntl, lying heiiraili the ct^ntm] iicrvoiw i^ys-J 
tern, is [inxhiciKl iHjr. 93). 

The ri-m:iiinIor of the olionlii cn<kKlenn grows out on rach side betwoeii the! 
cotixleriu and endtNlerm to form n |)lnt4s of tDe^tMlerm, whidi displaces or ijdIicki 

with the nieHMli'rm ali-esidy |ir<-M-ii1. 
The plates do uot long rt^niain nim- 
fde, however, but become sepamted 
into two layers (Fig. 9:i), one of 
which becomes eontinuons with the 
i-xtm-ciidiryonic ^oinatoplciirf and 
till' iiiIht with the splanchnoplciire. 
The oavily which scpanites thftiD 
two layers is the embryonic co-lniu, 
and i^ continuous with the c^rre- 
Epondine exlra-cnihryouie cavity, 
'rhe Ajilittinj; of tlje m<-.»MxlerniaI 
platPH docs not, however, in lh(> 
lugher ninnimnlia exienil ^uite i« 
the inner edge of each plate, but 
only to a longitudinal groove which 
has apfK-arrd, marking off a «arn>w 
|)ortioii of ciieh plate iniiuedtately 
exlcnud tn the median line of the 
body. This uicdiiui bund of meso- 
derm now beeoirie* iHvided by a 

ecritw of Inirmvcrsc (-onstnclions 

Piri. !n.—Fi>rniBtloii of ptiinltlv* xroak and msdullu-y :„,. „ i,. _ „r ..t.i ._ 

imovoi. (KiiiiikiT.) 'nlo A nnnnH.*r ot oblong niai^iKv, 

whicli have Ix-eii lerini-d urohvtr- 

ttfbrtt, or, better, mejtodernml «omUfJi (FigB. fi."} and 91), the li»,»ne which lies 

honenth the gnwjvo HcjKiniting the*c from thi- mcirc liilemi [Kirtions of the plates 

being termed the irilfrtnrilhlr cc//-m«w(. Tlie foiiiiiitiou of the -oniiler* Iwgini' in 

what will be the neck r<;gh)n of tlic embryo, and thence extends tioth forwan) mid 




I 




■ PUNCH- 
NIC L4YCII. 



HOTaCMOnD. 

■oara. vi •»■.■. 

Pii>. n.— TntiiiTcni' ippUiin Uirouik ilor»«l rtKlon of cmbfyo, 

baekwiinl until the medinn iMirtJon-i of ihfi meso<Ierm of the trunk and neck 
K^ions of the InmIv are divided into fsomites, iiidiealions of them also occurring 
in the head region. 

A-i the i-ettult of these changes the embryonic disc han liecome diHi-rpntialod 
into several areas. Along its median part is the central iiervoiis system, the 
meiodermal somilPfi, and the intermeiliate eell-mawe<i. these fiimiing the embry- 
onic area projier : external to tins is a region where the <\\i^ presents a somewhat 
transparent apwaranec, and this is termed the nmt prlliiriiUi ; while the niOftf 

Kripneral portions are opitquc and n-ceive the niune of the «»^ti o/toeo. tn thi» 
\% region extensive changes have been Inking phiee in tlie mesoderm : some 



THE UMBILICAL COIW A AD THE PLACEXTA. 



83 



of its «*Il8 amnpe tlu-m&olvps so as to form a m-iwork of voniii, into the *iib- 
sbince uf wliii'li flniil [iL-rK-tmi^s from ihc tiiirroumliiig lUsiies, the conls boinj; 
lliii^ I niii*l<iriiit'<) into mtiaU in which IJc tiumcrouf vollii. These cunnU arc h)ou<l- 
vcMvIt ; the fluttl >vhivh they cutttain IxTomei^ the pWniu of (he blo<i«l ; the miler- 
m«)«t «i-1Ih of ih« ori^nal n>nl« lluttvii luid produce u thin ivhII for t)ie vm»(>I», 
while llw more cenlral oell* i^nnip liiemfelvw iniii innKse'^, whieh iirojoct here iiihI 
there into the inierior of th<! vewwlsn from their walU, attd nro termcfl the W/km/- 
uiiuxdit. An abiiiKJant uelivork uf bluud-vcMieU tmvervii^ the arm ufiaca is thuH 



Cr^EH"'^^ vi«ie:ii:< 




cmoDiaiML 
ARIA *CltUCLOA- 



HIOUlUtHT TU*C. 



IHO<f*OrD4V 

• INU» 



■*■• ar<ca> 



Fis. M- — DtTtlopnicnt of •omItM. 



rrctlul.) 



fomied, thp inter\'al;< of ihe network ht-iiij: oocii|>ie(l by ma^t-a^-s of unspoi-mlizpd 
cells, which arc termed inih><imief-Uhmd», and later give riw to embryonic oon- 
neeiive tissue. Toward the periphen.' of the area opaca a circular hlootl-vessel, 
known as the Wmu ttrmmaiw, '\% formed, markitig the ciitrdne neripliery of the 
vascular region ; an<l. ihoo^ii the area ojiac-i may extend beyonti this, the blood- 
vo*selB do not, and it is tlms jKissihIe to divide the area opiicn into a nu.irc central 
iii-»vi ntm-iiloitrt and a more pcrit)hcn»l »r»^a opaca pn)pcr. The foniifHioti oi' bloinU 
ve**e!i« lieiiin" a little later in tn« artii [k-II iictdu, ati<l thwice ihvy grow in toward 
tli« Ijiidv of ihe embrvo. 



The Umbilical Cord and the Placenta. 

The embryo dnrinK the e:irly (stages of ith development forms a flat disc, 
whieh m.ay lie rena riled as resting upon the surfaw of (lie yolk-«ie, and forming 
ific rtiH.r of the umnii>tic cavity, its pclixlcrm and i-oinatoplenn- beint continuous 
with the wall enclosing thdt cavity nt tin- eilgcK of the embn-oiiii.' iliw. At it* 
hind end a lliiek i»i-<liclc, the Iwlly-'talk, eiinipux-d i)f nu-wiilerm, nnilefi it to the 
wall of (heembrt'onic! vewieie, which i* now known an thef^/or-i'oti.and into thci^nb- 
stance of the l>elly-:^liitk there prujeet* a fmiill diveriieiiliim of the volk-r>ao, whieh 
represenl!* a rudimentary it/liiutoix, a striieiiire lai-gely developt-d in lower form^ in 
which it spr%'e« as an organ of respiration and -lecretion during embryonic life. 

While the changes above described have been taking place the embryo has 
begun to dMistrict itself off fronj the yolk-«ac by a tucking in, as il were, of its 
mora peripheml jiortionfi, iw that it (gradually becomes transformed from a dis- 



84 



EMlitiYOLOar. 



coidal to a cylindrical etniniiiv. Tli<- lucking in pmo-iiU tiioiv nipidly ri-ma' 
before bm-kwan! tbaii in oiht-r direeiioiis, and conotnels the yolk-Kic, convening 
it into II |H'!ir-^bji|H-d vt>§>ic]e connected witb ibe interline of ilio oiubr>-o by a nnr- 
row slwlii (Fi^. 9(i!. Kvciitiially tlie tucking-iii pniccss results in tbe complete 



FICIO. 




Rr^. K. 



CHCltiOhic vim 



«r4.t.>-tT«LB 




FiM.%*ndM.— Dliignniaorisriloni IhrouRli ihv human ombryo In •MiF «U«es of deTClopmfent. (Xodl> 

llrit tttiai itntr i'pKr.l 

cloMire oi' \\n- vi-iitnii fiirfitn- ril' ibc eiiihrvii oxtvpl ov«t ii small !in-ii, the mnhUi- 
rt(j>, ttiniLi^li wbic'li tlif st«lk of tin- ycilk-^at; niiil tin- hflly-stiilk )ijuis. Kmtn tin; 
marginii of thi^" aiva the Imdy-waU n*iw become-* n-flpptt-d oinwiinl, iind fin'bwcs 
the two structures in ii foiunion investment, tbe oord so fornietl being known as 
the umhilicn/ cord (Fijr- ■•")■ fiince tbe edyes of the embryonic disc are conlinnoUH 
with the wall of the amniotic cjivily, tlii§ is carried around the embryo during the 
tnckin);-in iinx^vss, and us the iKidy-wnll grows out over the stalk of the y(ilk-sa« 
and l»el]y-t'talk tliciuunion isalw>e:irriedouI until itsatlaehment I" the embryo is at 
the outer enil of the iimbilieu) ooni. mid tin- embryo han^t- siisiH-nded in a large amni- 
otie eavily (Fig. i}7). Tiie nii'*>)deriu whieb the umbiliod oord vontnins becomes 
eoiiverted Into a [H'euliiir jellv-like ennucetive tissue, known ;i!H WImrlon'* jellv, 
in wln'eli iire indied<led tbe ru<limi-iilitrv alliintoiii and the volk-wiu', and in wbieh 
tlie luiibilieal aricrieii [msn out to (be eliorion, and tin- midiilieal vein |iii>ne» in 1o 
Ibi' '■mhryo. Over tbe entire extent of the eliorion nuuHiinis braiiebed iimcessc-s, 
termed <-liiirlimif rill!, are <leveloi>ed ; bnl the majoriiy of ibew? di^opiiear later on, 
ortiv iJiosi- King over the outer end of the nmbilieal cor<l persisting (Figs, flft 
ami 97). Tiiat portion of the ehorion iijjon which the villi persist is tenned the 
eAoriftn/rwi'/'wiiwi, while ihiit from which they disappear is the ehorion Irrre. Into 
each vitbis a loop of the umbilieni ve>isels passes, and the chorion frondosum forms 
the fii'tnl |K>rtion of the p/dtytifa, tbe orpnn by which the fnetal structures are 
brought into relation with tin' ninlerual (Fig. l'7i. 

In the meimtirae imporlant iIiiui^T'' Imve taken place in the walls of the 
uterus. The mneoiii' membrune lining it beeume* greurly ihiekeued, forming 
what is termed th« <lreidua wra, and thai |Miriinn of it whieh i» in eontnet witn 
the eliorion frondosum l)eeomos esjieeUilly thick, and its hi o»»d- vessels dilate to 




77//; VMHII.ICA L VOltD A XD THE PLA CESTA. 



85 



farm wide 6iinis4?-s iiilu wliicli llie clinrioiiic villi j>nywl, mi tliiit a pmhIv (xaniotic 
interchange can take plnco betwfen ihf inatcntul and (liial IiKhmI^ ilimn^li llm 
thin walls of lln? villi, jiihI the nntririnn, aw wpII as the ret^jiiraliim ami M-i^ntinn 
of \\k embrj'o, «iti tluis be carried tin. To ihis ^xirtioit nf the nteriue iniK-u-ia 
which forms (Ik- mutornul portion of tite placenta tin- name livcidua untilina is 







»f«inua viiu 



iTtBINC WKU. 



Fki. *7.— Ddacrun or cnrld utcroi. ihavriiiu rormBiion al dMlduir aud tilacenu. iTBlut.) 

a|>plii-<l. Final!*-, when tin- nvnni n-:ii-li('« llic uIitii." nfiiT liriili/alirtu, it iniliHU 
iiM?ir ill the niilnManct- of ihu innciMii, ami ihe iKirtimi cf ilt:it nienibrane which 
ihns covers the ovum becomes later the lieriiUin rrflrxu (Fi^. !*7). At birth the 
amnion is rupiureil, allowint; the fn«ii»' of the aiiiuioiie flnid, and after the birth 
of the Foitun the amnion and plactnla, tiit;eihcr wiili oihcr deeidnx- whieh separate 
frwm th« »-alb of the uteriLi, are cast oiY, fiiriiiiiig what i* knt'Wii a?^ tlie aflrr-birih. 
To rrtHni now U> the embrvo pnijicr. Al it^ lir*t M-pnnition frurn the embry- 
■>l)i<' iihieh) il \* pnii'ti^'altv ^ln>it;lit,bnl a licnd -;i»i]i niaki-^ itM-ira|ijKir('iit in what 
will laler Ik: the region of the nilddiriiin, the foi'e-br.iiu being beat ventmlly until 
it U aln»i»t nt n right ntigle to the n<.-it of the bmlv ; and, al 
about the wime tiine,a linear depre.-wion direeled ilr>r>n-ven- 
tmlly ap|>eiini on eaeh side of the neck n-gion, and gmduallv 
de^-pens until it :ibiiost nniti's with the eavity of the digi-sl- 
ive tract. Thi'' deprefv-i<in is known a- a hrnHchml deft, and 
is Huceeetletl by three others which develop (iiiecessively from 
before buekuiinl ( Fig. iW), When the second cleft \^ devel- 
up«i 11 swhjikI flexnre of ihc embryo iippciirs. the |>0(iti.'rif>r 
)x>rlion of (he VhIv iK-ing In-nt dorNtlly. ThJ" flexnre, how- 
ever, i:< of iliorf dtinili'in, ami h-uve* »o ]iermanent traw of 
itH exiitenee; but, when ihi- tliini bniiichiiil cIcH form", U 
third arxl tiiore piinntnenl thxiire appi-ar<, thin lime a ventral 
flexure ^itujiii-d in ihe ntfV region, an< I, iis thetlor^il (Hirlion 
of il>e l>o«ly also lietHimit" eiirveil in tin- ssuiie direction, the 
embryo seems to l)e coiled ii|»on itself. .Soon after the develop- 
roenl of this iieck-flesuiv- the limbs make tht'ip ap|K'amnce as simple piin^d, hud-like 
outgrowths fioiu the sides of the IkkIv, and. a-' (hrvrlopnieiit pnieceiU. ihcy inereiiw 
in size, and rudiments of the fingers iind toes appear. Urudiiiitly in later iflug<-;4 




Plo.«. — DL-velopiui'M 
of lh> onibno— am miniih. 
(IIU.) 



86 



EMHItYOLOGY. 



tlic brnncliml cleAit «li:^ip]H-:irorun- iiUKlilUtl JDto speml !^t^l<'ttllv■i not .lecii from 
liie pxtcrinr, die iValurvi' an- jinnlimllv dcvdopttf, llie iieck-flt'xure Htniijflilonit 
niir, iind by ulx'ut \\w tliinl luonili nf «k-velo|)iiteat the embryo hau ncqiiired a 
distinctly biitnaii H|t]><'araiic«'. 

It will iiuw, afii-r this nki'trh nf |)ic ruriiiHtiini of llie embryo, bo cnnvonirnt 
to poiistdir tbi- dcvi'lopnirni of ll»- iiinn- iiii|HirlHni >irpiii>- nf the bodv, and tbt^se 
may Ix? ^roiipwl acrfirdiiijf U> the gt- mi- layers fnmi wbicb tliey ftrv i»riiiri|«illy 
ibrinf^d. For uonv<iiRiict' the dcvi'lopmpdt of tlie orpiiM- derived from the 
eu(l4>derm will first be coi^idered. 

ORGANS DERIVED FROM THE ENDODERM. 

At the stajje with whiili ibi- ilf^criitlioii ul' the ti>niiatii>ii of the gi'rm-layoi« 
emlwl the tn<h«liTiii fornuHl a tii!«' cln-H-d m cither end, and Iinviiiji «iniu-<'i<Hl 
writhittwo outgmwihs, the umbilical rftalk and the alIantoi.■^. An examination 

of the surfaee of the embryo at thi.-* 
stajje will -how un irregiilur ilepre^- 
sioti up|M*ite llic iinteriiirend of tile 
i-tidmk-nnnl tdbe (Fig. !ti*). Tliiw de- 
pr«wiio» i» the onil niHiti, or i^umo- 
f/(ri(Hi, find it i;^ bounded in front by 
the edge vf ii niediiin fojil id' lii^iic 
known iiJ" llie Jrimfii-miiKif procriut, 
while (in either !<ide i< it >-!«hii|K.'«l 
riilp", the unterior limb i)f wieli ridijc 
iH'infT ti-riiieii tlie iiuixilliirij, iiiul tlie 
itiijilericir itie iinni<llfiiifiir pruffKn, 
The thin {tariilinii whieh furnis the 
floor of the oral sinns simhi rn|>1iiri'ii, 
in eomniiininitiiiM with the exterior, il« 
ei'liiilerin iif llie ^inus. Sum tifu-r ihe 
ridfji'-, giinviiig towani each other, meet 
with the fronto-tiawd process, and, in the ennneetive li»»iie wliieli the two enTilain, 
the maxillary bones develop. From each of tliew bom--' ii horixoiitiil Inmellii 
(jroWK inwiird,)ind niirtw with its fellow of the opposite «iili' iiikI with e"rn.'*|>(md- 
in^ himeihe from llu- [Milittiiie bones bebinil, and the haril imhile i.i iIiiik formeil, 
■x'|uinttirig Ihi- orijjiiiiil moiith-eaviiy into mi i)p)>er or na.-iil liiid a lower or ortd 
portion, tlii-M- two eiivitieTt i'ommimie»tin|; Itehind with the iip[KT or jiharyiigeul 
part of the intestinal tnlic 



4 



>R«iiTa'»*i*i.' 

□ LriCTOHT. 

nj. 




(III.LAIIT 
PRO CCS*. 



Pin. ML— Devflnpinpiil iif lliv Ihrii 



and the eiidoderiiiiil (iibei»thii« plaeed 
endodemi lieeomini; eontiinniti> with the 
month if thus formed the two mnxilhirv 



I 



The Teeth and Salivary Glands. 

As early ns the uixth week of ilevelo|iineni there a|>i)earFi. <lippinfr into the 
lower und upper surfaee^ rejipectively of llie maxillury ainl nmiidilnilar procL-sscB, 
a tliiekening of the wtiHlemi, whoKe cell"' snlfKcijoently arriiiipe llieimielves into 
an antt'rior and |H)^terior layer, the "[xiee whieh apiM-nr^ b.-iw<'iti ll»>e layers 
fK'i-tmiin^r the pnmve between the lip and the ffoni ( I" if;. MMI). From the |Hi»te- 
rior Inver n liori^iontHl ridfre prows inwanl into llie ."iibstaiiee of eaeh from, 
forming; the ilruM nln'if, and npoii the under or upper siirliiee ol' eaeh .-helf ten 
thickening arisi', eaeh of wliieh fornm a nmn- or le.-« ir'"h"lar mass of cells, th« 
ennmrf oi-f/ini, coniieeti-d with the <lcn(]d mIicU' only by a narrow m-ek which nlti- 
matvly diNippears. In the nic.«oderni beneath each orcan a rapiil piiillteration of 
cells forms a iiatiilta, over which the enamel orj.iiii \> folded tike :i enp. those in'IIsi 
of iJio [lapilla wliirh an' in coniaet with the enamel or;,Tin bi-ooniinn, like the ontcr- 
most celln fif the latter, cyliiidrieal, and fonuinj; the 'nlo)ilofjt(iM, wliosi' offuv it iii 
to dejKWiit the dentine between themselvco and the enamel or^n. This they bc^n 
to do at al>ont the end of the fourth month of development, and at about the same 




£RA!fCBIAL CLEFTS AND STRVCTVBES DEBIVSD FHOM THEM. 87 

tinat' the tnamtl bfjfiti^ Ui W formed by the lower eoAs <if tlie tl(?e|>er layer of cells 
(tf (h«> eaantpl urj^ii lHX.i>iiiiti^ tnin^^fumied into cuk^reitii!^ pri>-ni<i. Finully, around 
the uutfiido of that purtiuu of thf papilla which is nut covered by tl»e enamel organ 




Kiu. IW— Ullfmn of Uio ileri'lupaivnt e4 k Uiolli. 



iIktc; »p]M-iiry, iilwiit the fifih month, h dopmitioii of bony matter derived from 
moixlenmil tvll» nnd eon-^titntin); the vemrnl. 

AfUrr the M-i«ir«iiiin of the i>Tt]itfr''n of the milk lei-th from (he dental shelf 
the latter enniiitiK':* tu sink divprr into the ^nli'^tiinit- of tin- jitiv, niiil ii)i|)(i!>iltf 
Kii4i milk toiitli n mrmul rntmirl wif'tn aTiM-K from it, iinil, mciaixlermnl ]iii|iillie 
aUi forminii ii" Itefon-, (lie iiiihij^'ii of l!ie ])erniuueMl iiieisurs. ejuiines, niul piv- 
molar)' art- formcil. The {K-rmiinent molars ariiH- in n .similur manner from n 
latent] extetL-iiim of the dental tihelf, and il-* hooii na all tlie anhurvn are forimtl 
the liMiie of the sltelf in the intervnU between the variou.-- let-tli lie^inn to (tiMip- 
pear, (teciutionally, however, pehiiriting in irregular ma.-(«e!i until iidnlt life, and 
prudncin^ various ahnormnlitie-i. 

In addition to the teeth eortain ;^'landiilar stnietnrrw develop from the epithe- 
lium of the oral cavity, the most important of whieh are the *alirari/ t/fanih, 
which arise as simple tubuUir evaginations, and gradually, by branching-, become 
more and more complicated. 

The Branchial Clefts and the Structures derived from Them. 

At eaeli i^ide of the pharynx there are. t\s already staled, four furrows ( Fip. 99), 
rcpresentcl intenuilly by ciirrc>|M>nding depressions, so that along esteb furrow the 

fJHirj'nsjml epithelium is in «mtael with the cclotlerm of the surface of the body. 
U the lower vert<'bnitej:' iietual iKTfi)nitit>n of the Ihtii niembnine so formtil oecuns 
forminj; the {rtlUiiit^, bni in biniK mid inainniids liie |R-rfonitioiis lifi not develop. 
The fir-1 rumiw lie.-< immediiiteiy (x-liiiid the mandibular pitici^i, and i>e1wiH-n the 
momlHT^ of laeh nmfs-s^ive |iair of furiinvs is a liiiekttied riilf^e, I'oiiHlituliu); ii 
branchial nn'h, eaeh nn-li bi-tni; bomolojron.H with the maxiilo-nianditiular imi- 
cNs&«, which really npri-nent the first ari'he-->, the numtli liein^ die lirst branrbial 
cleft. As development progresaeB the second arch of each side growH more rapidly 
than the others, which arc in consequence pusbetl inwanl toward the median line, 
and a tkep depression is formed at the side of the t>eek, tliesooM pnteriTmi/is. 
Krom the posterior edtp- of the w?e(>n<l arch a fold (rrows baekv.iird over tlie 
mouth of ihtH KiiMis, and eventually completely cmvci^ it in by uuitJug jiusteriorly 
with (he sikIv of the UkIv, 




88 



EMBRYOLOGY. 



Frmii iir in crmiiu'i-tion with (he branchial arclit^ or rli-ft:< a iiuhiIht r)f »truo- 
liin-j' (Icveliip, i*om<* of wliioh may l»e con.xiden'd hero. I*'rmn ihc rpilhcliiini of 
till' fmirlh (lair nl' ch'fln Iwo thickenings Hevolop, iiiid Hiil)Sfi|ni-nrly fiw roprihciv 
llii' niiii^lt- mass so liinn«l {rrowiiig iKU'kwartl Inward ihc |i(-ni-ar<li»m, M-{mi-:iiiiig 
fnim th(' cli'ftf, and cnlarpiig bv bnim-liing al ii.- piisitricr cud. ll flirm.- (be 
Ihipnus t/laiiil. whoso <-|)i[heli:il milage bwonifs early infiltralcd with Iviiijihaiic 
tiHsue, and which, subsequent to the second ywir atlcr birth, bc;fins to iindergw 
degi'Uerativc thangcs. The thyrohl yUmil arises i»artlv from the last ]Kiir of clefts 
us pairetl hollow cvuffi nut ions, and [Kirtly frtmi h iricdiEin eviifriuatioii of the floor 
iif the (ibiini'nx in the vicinity uf the wecinid hriinclnal arch. These anla};en early 
fii«' lo(jcthcr, and ibc {;lnnd iisnully Iokc:* all connection with the }ih:iryn!C, the 
foninieir niH-iiin nt iIk- biisc of the ton^rue rcprt'suniing, bowevt-r, the plaw of the 
origin of \\w nuiUan nnliiiic. 

The tong;uo is, onibryologically, ]iartly a jirocUict of the iilmryngi'ftl region, and 
nriw-H from two antigen. It-* anten<)r portion arises n^ a (bickfiiing of ihe floor 
of th<- oral eavitv, its baek iHHtion, however, developing as a )mir of ilnckeningit 
siluatwl in the vicinity of the second and third br-anchial juvhes. These thicken- 
ings extend forward and outward, forming a V-sba()ed mass, which encloses in 
front ihc" posterior end of the anlerior aniage. The jnnetion of the two anlageii 
is indicated in the adult by the V-shaped grinne iu whicli the ci re iim vallate 
papillie uri' situated, the for»mcn ciccnm, already n-lcrrcd to in connectioii with 
the thyroid glaiKl, lying lU the ujicx of the groove. 

The Trachea and Lung^. 

Below, the phannx eommunieate.H with ihe tubular rpsopliapiis. and on tfifl 
inner .-vurfaec of the njiper nan of this ibei-e early ap|iears a longiludinal gHKivc, 
from the lower end of which two pouch-like outgrowths develop. As sixiii aft 
these begin to form th(' groove begins to be eonstricted from iielow upward from 
the oesophagus, and beeomefl the trachea and larynx, the eonstrielion not contin- 
uing to complete separation, so tliat the larynx communicates alnive with the 
pharvnx. In the connective tissue of the walls of the trachea cartilaginons 
rings develop, the upjiermost of which form the crii-oid an<l arytf'nioil cartilagen 
of the larynx, the thyroid cartilage being prwiueed by the fusion of the ventnd 
ends of two pairs of «irlilaginous bars which arc |jrimarily »lcvclopcd in the 
mc&odcnn of the fourth ami fifth brunchial iirohti'- The pondi-likc luilgrowtlis 
are the anhigcn of the lungs, iinil at an early Mage become lobcd. three lobcj" 
appearing in the right lung aii<l t\Mi in tin- left. Si-e<>tidnrv and It-rliarv saccula- 
tionis later ap)i)-iir. and the ci>ni]>licaU'<l structure of the adult lung In aci|uiri-(). 
It IK to be niited thai the c[)itlieliiim of tlip lungs, tnuilica, and lar^iix U of 
citdudernial origin. 

The Intestiiie and Mesenteries. 

From that jiortion of the primitive intiMlinr- which siieeecdei the (e^iojihagus 
the utomach and in|e>iiiiiei", tngi-thi-r with the liver and imncri-a.-". di-velop. Of 
(he two xtiuctnres which iu enrly cndjryonie life are eonnivtcfl with it, the allaii- 
loiji «\\T\y .■^■|Mimte», il.i inlra-enibryonic |)ortion juM-sisting as the urinary bladder 
and the nrachnii, while the stalk of the imibilieat veyieje retains its eonnectton 
nntil arter birth, the intra-«mbryoni€; portion of it occasionally persisting even 
int»> adult life as a more or less pronounce<] diverticulum of the lower part of the 
snuill intestine, known as Meckel's diverticulum. 

At first the intestine is a simple straight tube attached to the dorsal wall 
of the alxlominal cavity by a dorsal mesentery, formed by the reflection over it 
of the iK-ritoiical lining of the abdominal I'lcloni. It* iipjMr |H>rtioii i« also 
attached to the anterior wall of the abdomen by a vcnliiil no-Miilcrv, who.-^.- 
lower border i» falciform in Klin|)e, ami is attaohed to the abdominal wall at the 
ii[ubiliou«. Thi.i simple arrangement, however, soon dif^pjieiirs. as the iniei'tine^ 




THE I.VrKSTiys A.\D MESEXrERIEH. 



89 



,.avntta in len^h niore mpidly than Iht- oiivity iti wtiicli it Wv*. iw |Hi<lKit mit 
dUi a loi>p, ii.'i U F(-[>reflCiil(Hl in Fig. IDI. Tlu- climjfution cmiitiuiiing, tlie liKip 



MMCIROIWM 



•U»*CH>OB 
iia er uvc 




'■■ULCR «itiiimiw. 

iVLCtM. 

iTOmmcH. 
[»oaikaii(>uin. 



Pic UL— Diaina) «r th* liunma mwHUtury lii lUiirlmllliynlMloiu |C.^ MlnaU 

ben<]s npnn itwlf. tliiit purti'in of fhc intestine wlitcli will become the Iranitrn-se 
eaiun jmiising over tin- |Hirtirni whidi U to become the ilutxUnnm. Iliiring the 
etongntion of thi- itiIi-nCiiic tln' i-tlfjr- <if tlie dun^il inewntcrv which in attiichcd lo 
il Hn*J<'rpi(-s a oorri'sjHincliiii.' iiic-i-tiute in h'li^th, while ill the line ol' iiltuchment 
to the iMxIv-waU il imrf^iscs but slightly, the nnwiiivrv wf tiio Iwiip in oousc- 
<jui'nf<> iL'i^iimint: :i t':in-like lorm, nnd, when the twiitting of the loop snpcrvenee, 
becoming fitnntj-like. 

By una timu a dillerentintion of the iiitii'tiiinl HiIh- Ihw iH'enrivd, the {Kirtion 
of it above the loop [jccoming enl«rjrc«l to iiirni the nlomiu'h, while the |H>rlion of 
the loop which pa.-wes Iran aversely ;ien>!w the iiliiloniinHl i-jiviiy uml the |>ortion of 
the iDtesline Iwlow this iM-oonn-. the /ui-ijc iii(ci(jii.'. Tlur ritimm ilt'Velojw iw mi 
onigrowth from the lai^te ime.-itine at the |K>int where it is joinrti by the fiiiiil! 
intestine, and the Vfrmijorm appendix in an outgrowth from th<r cowiim. 'i"lic 



AMBitr lamillit 1/ ffrpairr oiuiniuiu 
ntUriarlmmtBiiv S'f^' witiuuni 



Orttiltr uiKoi/Bm 




DttphroffK 



tint 



I»HT atNCiftim 



Awaiui 



Xfucdnan 



- Stettnlrry 



Smuii iixattw 



Fift 101— DIainin to llliulnic Om hlilury of ihc human mtunteiy— culler lUgir. (tlvrlwiet 

forthpr cltanjBi» in the intestine eonMr^t principally of a continued elontratlon, 
»«»«ri:illy of tlie miall intrnlinr, and of the <Hvnrrenec of fusion and dosreneration 
or certain iwrtiont? of the mesentery. Thus, the mreenicry attaelicd to the tnins- 
vettm oolon, pn'miirily rudiiiting fniiii the ajx-x of the mcHenterinI funnel, later 



FB" 



00 



EMBIlYOLOaY, 



«xtend8 its infiertion latfrally ilium i\\v lK)(i_v-wall, formiDg a transverse sheet, ' 
mes»cu)on. Tills {Missing over tiio (ItiuiU'iiiiii] binds it (net to thi- |Misterior wall 
tlic ab(i<hiiun. iinil iis a rcsiilt tin- iliiiidciml nicwnkTv ilcpfiicrati'-i. Tin? iisiTriMlini 
ami (Ifficmliiif; oili'ii Iiktwisi' iiimi.' lo Ik- in (oiilud willi llii- ubdonnniil wiill.auc 
thi-ir iiKwiitrry ik-nfiursiU-s \'\ a wrtuiii oxlriil, llicir lower jwrtioHs bi-iitg only 
riiv<-nsl, iiiitl Dill (.'iii'lo^di, t)v {H'ritiiiK-iiiii. 

Tilt.' Klmniifh, in ilii' iiii-jiii liiiit', Ihlh iiIm) btfii iin<l<-r):tiin^ <rorlaiii rhnnf^';> in 

JiOi>ition. At lii'iit It i» Nirutglii, ulmt later lKH-<(imi.--« tlii; small nirvHliirc iK'iiie. 
Iirect€c] aiitt>riorly ; liut rtixm iIk iiyloritr on<l Ahil'is [>\'cr towiml ilic right ^i<)(* of B 
the bocix', nnd, at the same time, tilie entire ntnieturt> Iwi-it.^ in muJi ii iniiiiiicr tha^| 
its oricinal left siirfeoe becomes anteriur, and llie small enrvaiiiri' i- directed tof 
the riglil,' As tJie result nf thin tlw- |Mirtioii iif the <i"r^l iiiiM-nieri' which is 
attsehc«l to the siontaeh iKconies thrown into a ponch Ivinj: behind the sKimach, 
the cavity of the |h)Uc1i fortuin^ the omental eavity, and its Honr later lieirifc drawn 
(lownwunl lo form llie ^rvat omentum, the po.-torior layer of which, as ft ptisses 
baek to the biMly-wall, ftises with the mew>eolon. 

Oiiriri); fhc {irufircss tjf these cliiiiiges a mir of outprowths have Iweii develop- 
ing friiin llieilmxIiMiiiii hikI piif^iiig lorwani between I lie two layers of the venlnil 
iniM'ntt ry. They iiiiitf lo fnnii the /tvrr, whieli (juiekly rcsiehes a lui^- tiw — «t 
lai^-, in fact, tliHl Ilie two layers of tin- mesentery eaniiol quite meet urouud it^ 

Una 



SItmatli 
Tnautent tvlati 



Qttala amentii'B- 




U imre m ail m t 



Panrnta 

Ffi <i! "mnthrm tnclonaf panetBia 

()ii«l(iu™ 




ManlfTn 



.tmiill inlrUtat 



Fill. 103.— nUsmn to lIliulrNlif lliii Iiliiory ui [tii litiiri]iii iiii'iL'iiIi^rr-liiU'riiliwi.'. lltrrtxtg.) 

hilt are refleetwl from its sides a* the eoronary HiriiiiientM. The ii|nn-r )H>riioii of 
the mesenterv. above the liver, reniuins iiiichiiiif'i'fl, how'ever, foriiiitij: the faleiforin 
tiffameni, while the |H)rtion below is alVceteil by the torsion of the stomaeh, so (hat 
its faees wnie to He dor«j»lly aiiil vcntnilly, iii.->teiid of right and lei\, and it format 
the sDudl omentum (Fig». 102, 103). 

The Liver and Pancreas. 

The tira" ariws a* ii pair of hollow oul^trowlh" fnim thp ventral surfaee of the 
npper part of the ilniihiiiim. FjieU out(rrowtli, wbioli represents one of the lobes 
nl the adult Hver, iMVi-nn-' gnTitlv eomplieiitiil by lln- ilevelopmenl of numerous 
Intcml solid bmnehes, thcte developiiifi other«, niul so on. the various branehes 
uniting with one nnoth<?r to form a network in the meslies of which are found 
capillary blood-vessels. The s«>lid branches, termed hepatic fyfindrrn. become 
eonvert<Hl |uirtlv into bih'-^HcIji and fajiifinrloi bv hollowing out, and partly into 
the lix'er fiafciiefii/mn, the ori|^iiuil network (wx-nniing more or less ineonspicnous. 
The v-urious bile-capillaries unite to form the right and left hepatic diK'ts. which 

' It nn*' Ix." iMJtiitiMl 1.1111 lliit llii« t"i'firiK i- llie i-hiit >if iIh- ]iiwitii)ii of tlii.> imcnmoKiinric mrvm 
in tlicjr coiirw owr ihc Homnch in tlie adult, tbf Irfl iiiTvi- pumtxii in frool of anii llie rijslil imrTp 
hehlnil lli« Tiu-iu'. 



OROAXfl DERIVED FttOM THE MESODERM. 



91 






first open !^'t<arntcly into llic «lii<K)cniini ; luit lutor tbv (liuKli'iiitm Ix-comc^ 
_ juchwl where iWy i-nU-r, uml llii« iMiticii !> ilniwn out tit (i>rtii tin- itaamon liUr- 
fluftf ffjm which ihi' ijiill-ftltnUhr rik) i-^idir <liirt nrm- uji ii holldw ■■ vagi tin I inn. 
The powmw nri-'L^ »» » imilow uvii{;iiuiti<>n nf (he tl(irT<»l wull of tho ditotlo- 
niim (>[i(w«iu- th<- [toiiK wlicn> the liver aiila^^n uji|)<-»r, uiid ^rowx Horirallv bctwc«ii 
,r tw'i layor* of llie dorsal nipsentery, gmcliialty bcvoming verj- diuHi branobetl. 
t in alHtrUtl by th(- torsion of lh« stoaiach, to that it a-tsuoies a transven^e poMi- 
ti'iii ill thi- iilHloniinal cavity, awl on the development of the nie?:oeolon L- piiFilivd 
with iht- tliKHliMiiim against the don>al wall of the nlMloineu, it?* mehentery m «in- 
rtMiuonoo undi-rpiin^ deg<eneration. Its duct, whieh ut fin-t i« attuetit'd to the 
dornal iHirfiiee of the duodenutn, cmdually moves around toward titf vfutt«I 
Borikce, and 6nnlly, as a rule, uqicoh with tliv conimuu bile-duct. 



ORGANS DERIVED FROM THE MESODERM. 

Tile primitive layers of the mt^odtnu have their ecil8 iirraii)ied at firet in nn 

lilhelial m;innrr, and ihim urTOn)^-nii.iit is prvverved by certain portions of the 

venf for a (Minsiderable time, evt-n, it m»v be, throii;;lioiit life ; to these portions 

li-mi menfitMium iiiny Ik- npplii'd. At (vrtain r<ijions, Iiowcvcr, cells arc 

bnddtil lift' from (he pi-iinittve liivers to form irn-^ulnr miLSfK.'-s "r bet'ome NCJit- 

nnl ihrrKighmit lh<- IhmK' without any drfiiiili- iirniii^-Tnent ; and ihe-^e w\U lire 

nned Jitftn'iiriiinMe. It h piKvilile, !n aci-onlance witli this divii>ion of the 

nn, to recogiiiz«^ niejMithctiiil and nH'j<i:-nehymntoii^ organs. 

The Skeleton. 

From th*" mo-'icnphyme arv ilt-riv<il the ooiinpetive and anp]>i>rtive tisriiieti of 

ibi- tKMiy. whiK* histol'igieal ditl'i-rt-ntiulion need not be eonsiderc"! here, A tvw 

i»lii!<'iiii-nt.-> nmv U- made, however, eoneerning tUe development of the skeleton. 

The tir^l trace uf a .lupporlivc etrueture iu the ombr>.'o is the notochoi-d (Fig. t(H), 



■■fc eona. 






(i»T««Hoaa. 




FlQ. l»l.-CruuMrc(ii>a at cmtiiyo. 

itwc formfition hac already bwn d»wri!)e<I, and whieh i^ nntetieiillv a Iransitoiy 
Uriiclnn-, lj«-in)r replaec<l hiicr by the i-iiimil eolitmn and ^Knll. Fr-irn a |H>rtion 
•^vmch of the mevtKlernial f^omites a miiv< of cells is budded off. and thex' nias.-<c^ 
lujn- l)ii'iiiM.'lves on eillier (ijde of the nntfK;li(inI, which they cventiiallv cneloMC, 
pmwing dorsally at the same time around the npinnl cxini. Eneli mesenchymatoua 
U&ifi so produced by lIic members of «ich pair of memHlenual soniiten early Ix'comcA 
■^ivertwl into a mai- of hyaline eariilaK*-, which later <Bv*ilies to form the rnieim/ 
1 ; and, 85 the itssitieation ])nH^-cds, portions of the notoehord enclotted by the 



92 



EMBRYOLOGY. 



} 



.OLftCTONT •(T. 



njIBICIluC CHAHII. 






ci'iitni arc gradimlly envroui-lHil iijhiii unti tinallv ilisnpiK'ar, \\w iiUt-n't-ninfr por 
tioD» ]>cr!(istiiig II* llic gdatiiirtuji TXiMntioe of ilie iiiUTv<?rlfI»n»l diik*. The nmt 
airhfn dvvolup ii Utlli- Uu-r iliuii the cenlm, and ouify M-pamtt-ly, uniting with ttte 
ccntm only ni'li'r liiilli. 

Till- riViH amc by tlu' ohuntlrilicaiinn and siili^^fiiiK'ni atMlioaiion <>f tlif iiu'.-^-ti- 
rhymntoitri tissue Hitiiaied between llie members of ciicli lair of nierxxlermal 
fioniitt'rt, thp ribw of the thuracic region being, however, llii' 'inly ^m^.^'-. wlii<-)i 
undergo complftf devchjpment, extending hi the wall of thi- body to the ventral 
eurfiicf, where a nnmlHT of them unite to form the steniuin. In the other jM^rtions 
of the trunk and in the neck tbey n-mtiiti i^nijill, nnd Wcume untterl with the ver- 
tehnc, being re|i resented in the i-erviinil rcgiou l»y thi- veiitnd |»>itii«i* of (hf 
tr.inj'verw jinMLrsx*, in tlie Iniiibiir regiiiti by the viMtnl [nvt-ewfa', nnd in the 
i^iK-nitn by ttie bitenil musses. 

Tbe KhiU nbows from the iM'gitiniiig no tnief of being eompoMil nf ilisiinet 
vcrlebm-, vxecpt in fhe oei^ijtital region. The tii-^t trace of tlie sknll i.- foinxl 
in two ■■tirliluginoiu^ biirw, pliii'i'ii one on wich side of the anterior end of tbo noto- 

chord. These ai^e the pnrarhoi-thd 
carti/iii/in (Fig. 10')). and in front 
of them two other cartilages 
known an the Inibrciilir rntiiii 
lire (oriniHl. The-^e four earli- 
hlgcs <rventii:dly unite together, 
and tile Irabeenhe iiiiiling at their 
aiilerior e\t remit ie-* to form a 
[llat(>, known a.- the rlhm'i-riiiin-r- 
inf jiltile, a eiirtiliigiiiou<i biiMH 
crami is formed, which later ex- 
tenda dornally lu'liind and at 
the sides, li'tiving, however, the 
greater jiortion of the bniiii eov- 
ered only by menihnine. About 
the third month of devel<>|inient 
eenlre;- of o^i^iititiuion begin lo 
ajipear in thiii ehondn>K?ranium, 
rctiiilting in the formation of a 
It ^^"^^'{^-^f""'^"^"'*"'''*^'"^"- ii-S-Hiii"i.oft«w. iiiiiiiIkt of wjianite l>one«. which 

lalor fnwe with one nui'dier to a 
e^rtain extent to form the ocoipital, spheiutid, niid cllnnoid hunef, all of which 
are really eomiKinite lione.i. 

In aihtilion to the Imnew wliieh are thus developed, other elnin-ntK oireiir 
in the ttkull and may be arrangeil in three groiip> : (I.) A iiuinbcr of lionex 
are developed without being pi-efomied in cartilage, their oaseous matter being 
deposited directly in fihroib- eonnective tiitsiie. In iIuk wav — aw nuiiiliriinc biium, 
an they are termed — are fonneil the panetaU and friiiitaU and the Imne.- of the 
fiiee, »ueh u*. for example, the nasals, malap;, laehrymaU. imlalinef, anil uiaxillie. 
{II. ) Aroiinil eaeh amlitory orpin a ejtrlihipiTums eaw. the i»T!rif!e fijimtle, devel- 
o|w. ijnite irnlepiricleutly of the primary ehoriclro-eniniiim, lilling iin a gap in its 
walU on eiieli .«ide In'tweeii the (H-t-ipiinl aiui 7<phetioiil bouew. and from it are 
ffwmed the petruii" and mnntnid ]>orlions of the lemnoral, the MqiiamouK and 
tynipiinic portions being membrane Ikiik-:4, whieh riironihiriiy unite with the cap- 
sule, (in.) In eaeh bmiiehial arch a cartilnginoUH Iiiir develops, iher^e bars 
forming what iw termed the fincrifil skrtflon, and eerlain ol' them beeomc 
intimately rebted to the pkull. The dorsal end of the iijaxillo-niuiiiillinlar 
cartilage becomes entirely replaced by uiembrane bone.", the maxilla;, [lalatine^, 
and internal ptei^-goid plates of the sphenoid ; while its lower end, known ax 
MfekePs eartilaffc, oiwifie!i and uniteif with a nninherof metubraiie Iraiteit, whieli 
cncIoiM; it, lo form tlw lower jaw or mandible, and also takes part in the formation 




CCHCk.'a caitTILAOI 

(Mimoiauuiii). 



isiD HaniAOc, 






PEI1IOTIC 

.Htpauie 

on GLOSSOPHARTNOI*!. 



'"tv 



IlinTO0H»ll6. PatKCHOBSIlL 



"r 



"oo 



IBS** I Nmvc. 



TIfK HEART AXD BLOOIt-VKSSELS. 



d3 



I UP 

n. 



nf ihe MSflirW of llu- mnhllf ear. The purtilngi'w of tlw w'coiul ami thirfl arclwa 
uaite to form iho hyoid boiic, the Jiniall luirn. ilie MyIo-livoi<l ligniiients s»<i 'he 
ivlow] pr('i.'t'?w*p of tijp tcmiMtnilr^ reprw^-iitiiig the roinplpte fiw.'oiid arsh, while 
i<- f;r»<al horn rvpri'i^-ntj' thv inoutiiplctr ihlnl arch. The fourth and fifth arches 
)»e(v>mv gmitly rH)ttcc<l, and fuse toother, ii» nlrcndy indictitcd, to form the thyrutd 
rtiln^ of the lurt'iix. 
The tmnni nf Mr rxtivrntlir' itn- nil pri-l'iirmfd in airtiljifft-, ami for tJic long 
Imiw* ut lca»t Iwn <ir Mini- cciilrcs cif iis^iiticalinn iin- iiKCiiIiv pri^«('iit, one (n'iiij; 
for llic «l)u1^ iitnl oiH- for wich <'[iipiivsi,-, llic-v liirtt-r, hoHcvi-r, bt'iii;i mori'Iy 
pn>vinioti:< for llic pniwlli in It'iijrlli of tiii* IhhH', suhI not n-preseniiiig oi-i);iiinlly 
ilUtiiK'! l>om^. Ill till' "i^piiiii, howuvt-r, two primarj' cviitr<^ an- fonm-d, oih- for 
Iht! gnaitcr |M)rtioti of tlit^ butxt, and on<> for the <-oracoi<l |>rooes.a, tihic-h in tlie 
lower viTK'hmltw !.■* ii dt.-<lirH-l hoiip ; and similarly thivo priman,' centrss arc found 
in each Iii|>-lH>ne, one for Ihe os pniiiM, one for the ischium, and one for the ilium, 
euL-h of ihe.-4i- bciiiji iirimarily a di.Htinol bone. In the earpuii and larsuK certain 
fti-^ion^ alwi. iKciir. rvpically, eaoh connist^^ of nine Imhu'f^ arranged in a proximal 
row of three Imnex, a uii'tal row of live bonen. and a sin;;lc bone between the two. 
The following srhemi- nill ahov,- the filsioijB « hich have taken place, each cumpotite 
bnne owiifying from two centrei', tlie nwt from one ; 



f fir^iNj*. 



T(l IVH». 



Scaphoid, Itadiate. 

Seniilimar, Intennidiate. 

C'iim.'iform, I'liiare. 

(Fiiicil with Scaphoid) ( Vnlrale. 
Trapezium, Carpal I. 

Trape«.id, " II. 

(>Fi Majriium, " III. 

f " IV. 

't " V. 



Tibials, 1 . . , 

Interm;Hliate, }■*«'"'»-'"''"• 



I'nciform, 



Kibiilare, 
Cent rale, 
Tai>al I., 

" n., 
" III., 

" IV., 

" v., 



Calcaneimi. 
Xavicnlar. 
Intenuil Ciuieiform. 
Middle Cuneiform. 
Kutemul Cntteifnrm. 

■ Cnhfiid, 



I 



The piriform doen not belong to the name catejjiorv as the other eartial bonw*, 
being an osrtiliealion in the tendon of the flexor carpi iilnarifi, just a-* ibo juitdU 
i* an oMtification in the tendon of the quadriceps extensor femonw. Suoh boncit 
NTc known as Mu^amoid bonei^. 



The Heart and Blood-vessels. 

It hai< already I)een seen that the formntion of tin- blcHKl-viiMnilitr i^y»lcm 
be^ina in (be area ojiam of (he bhistodennic ve.iielt', nnd tbenee exlciidi< toward 
the emhrvo, two vessel;;, the rHil/lnir erin*, carri-ing the bIfHMl fnnii the yolk-«iK 
to the emnrjo. While the cnihryo is still snrca<l out flat upon (he TiuHaei- nf tlie 
bla^HMiennic vesicle the splanchnic layer of the niesfHlerin on each side of th« 
ImkIv Itndt' off A smidl eolWtion of cells (Fig. UHi. ••Httiiciiittiuin) into the sikioc 
Mwecn it and llie eniloiierm ; these early arrange themselves in a tubular form 
ami liet-onie ciiclosod witlnn a fold of the splanchnic nie-aHlcrm. These folds 
(Fig, 1U6, m}fOfitT<iium) and tubt« »o formfil arc the uiiliigt-n of llw! huirt, the 
two lialves of which are at first wi<lely separated : but as the embryo bcooinci! 
wmstrietcd off from the yolk-sac they are brought nearer together, and tinallv 
■mite to fomi a single doiiblc-Widled ttilnr. the fol<ls lieeoming the muscular walfn 
of the ht^^rt, while the mcscncbyniatoiis tubes form Its endocardium. 

The hfttri, thus fornieii, is situiitetl in the neck ri^ion of the embryo, and baa 
ronimnnicatiug with It behind the vitelline veins, while anteriorly it is continued 
iaio the aortic trunk. This simple luhular heart now nndergix** u eonifiderable in- 
rreiij«ein Iciiglh.uud. us ii result, betid« upon itself in an S-sliapcd manner (Fig. 107), 
(he aortic end lioing ventral to the vcrniii,«. The v<-iiihi.-i end now iH'gin.-i lo eii!iirig«>, 
inil poucli(% out into a >wf wn each nidv, forming the right nnd Irji anriett«; taui 



94 



EMBRYOLOGY. 



fntra itj* dor^ wall between the two aiirieles ii vortkal partition begins to form, 
which^ urtiwing liackwanl townni (he hori/imial [wrtioii of ihe heart, would M'\v 
ftrat*; the auricles completely wvre it not that a tbranieu forni-i in ittv upjier \mt 



HmuiDigu 




^ tout C«VITT 

•oviric Utn 



iBLAKHWe urt« 



•MICUI 
UOCMCIUH 




•Livinc mm 



(•WMXHie tiMWt 



(XBOCilDlUa 



wruLMti 







no. IDS,— Dniclopmcnl a( Ihu liearl: cnaawx'tlnni of the ecrviail rurion <it Mi embrroi dUirr*niuii>llc- 
HIM.) 

__V /«"»"«» wm/'^), wiiirh [x;n«iat!' until birth, «!o»i«g normally .-"liortly thereafter. 
The* iiartitiun pusniv li» the left of the o|)en!n^ by which the bliHxI fnun tin- vitt-llinv 




■ CNTRIChC 

nu. m.— Four iMtp>9 In llic drvptopiiieDt erf the h««n: front vl<n>; iHisimninatlp. (TnluM 

veiitfi flowH into the heart, ami, enns<-(|ueiitly, this o])ening now eoninii mi rales with 

the right auricle, the left rec\'ivin)r I'onr hiuiall vein« which come to it fiv>m the hiiig». 

The point of nnton of the mirieiilar and ventricuhir rt'giou.'" has in iln' mean 

timebtfomc eoiwiderubly wnmlricted^und the iiiirleiilnr *epltini cxtetKU far enough 



TUB HEART AND BLOOD-VESSEI^ 



m 



downward to divide xhe oiwnitif; lH-t>V(M?ii them into two parts. 

ujiward lowanl \\k- niiriciiliir •'cptiiiii. with tin- lower bonier wf which it titiit«>s. 



8 cresoeotir purtiliun dovclugt^i fniDi the iKM^trrior nnd 



the iKM^trr: 
. with th^- 



In Ihp ventricle 
lor^d udIU. aitd t;ruwB 



ending, howrver. In ii irw viX'^y hcm-nlh \hv o]M-iiin(r by which the smrtir trunk 
conmiiniir:itc<f with (\\v vi-nlriohr. Tiiv i"»iiv Irun}: ha« nnuinwhilc HitlU-iK-d 
dorstt-vcntrsiilv, iind mi ihft inner -.urfkit-n nf th* HhI sidi>ji two riiigiw ilevdoj). 
and (inulU iinil<\ dividinj; lh<' hmicn of ilic ntirtio trunk longilmlinnlly into two 
portioiw (Fig- 108). The partition extendi' down into the ventricle, and unite? 



niorii vtNTHmc 
A 




RAIT unioji», 

MKIKKMIAM 

OKNIM / gff 
I V 



MOHT nMrnicLi 



t£rT uinicuio- 



i^fl vEMiniCU 



no. HI 1>iiTi'liiiini«'nl of the korti atid iinlmoiitirT artniy. (AAcr Born.) 

with the frti- «hji' uf Iht- vi-ntrioulnr srgitiirn, su thiit tlir ilinmon nf the centridt 
becunio' pi>ui[>h-le, iin<I thi- imrtic trunk tluTi »i'|)iiriitcs ^•(^rlll)ll-t^•lJ■ into two tubes*, 
one nf which, the imrl'i, ciiiniiiiiiiiiiiii'.-" with the li-l'r vi'niricle, whih> the other, thfl 
pulmonarif tni*-rit, njwiH into ihi' rl'^iii viTitricli-. 'l'h>' original tubular heart has 
ihua become omvertt-d into a (onr-iliaiuliiniJ orjr.in which diflers from the adult 
heart only in the existence nt" the foramen ovule in the aurindar .iei>tum. 

The iiiirtic trimk, prior to its division, in passing forward from the heart gives 
"ff fnmi lime to time |«iirs of lateral hRincliw, whieh paw donially in the lirant^hial 
Wrhest. Tliet* are llie iri'iiic nce/if*. which, op eaeh side, nnite above the branchial 
clefbt to form a Ion);itiidin»l veirKct, and thiii. ]Klssing backwanl, unites with il^ fellow 
of the oppos^itc »ide to furiii the ihntal tiorfii {Figs. 109. 110). This primitive con- 
diiton is, however, iiicrcly transitory, the first anches eiirly diwipjx'aring. and then 
the se«>nd, ihciiniltrinutionsof the aortic trunk from which ihew arches arise per- 
i^isting, however, lo furm the t\Hn-iuii rmiytiii arterUi; while the bninc-heii of IIk" 
dor^aV aorta into which they opcne<l likewim.- peniiiit to fi>rm the intrrnni ramfnU, 
The third an'hw [MTsisI, bcciiniinjr |iortion* of the interntd e«mlid«, ami fonninf* 
the <imnwti'>it'' hctwccii Ihrwc inlcric!' tinil the exierniil cjirotid* ; but the nortion?^ 
of ihe brtu«'h<v* of ihc iIocmiI m.rta wliich inlerveiic helwecii the thiril and fourth 
arflit^ di.->9i|>|ii'ar, ihii.i entliiiy: olV the dii'ccl coiini-ctiiin.% of llie inleniiil canitiih^ 
with the dor!«jiI :iorta. The fourth anh nf ihe left, «ide persi-itrt in its i-nlirely, 
forming the areh of the aoria of the mhdt, iiml i."^ (he only eoniieetion hetwei^n 
the heurt and the dorsal norm, itinee Ihe riffht branch of the dors^nl aorta disafw 
peam oomplelely behind the thin! areh, the riirht fourth arch forrain(t part of tlie 
right nuMafian arteiy. The fitth ai-ehes (rive rise to an artery on each side, tlie 
pidnionary arteries, and the [Htrtiuu of the arch dlttal to the branch on the right 



96 



EMBRYOLOGY. 



Bide disappears, but pcrsistw on tlio left AAc to form tJie dudm arienoxua, imirinj, 
thp pulnmnary artery willi the liuiNal aorta — h connt-ctiou functional for liie 
passage of blood up to binb, but aborting later. 




8"S 




veRIEBRAL 




0UCTU5 

Ihteriosus 



PULMONARY 
AORT* »OHr* 

yw, ltl9.— Aiirtip •rohe«. »»rly Brrangc- Fio. ]I0.— AotiIc »rflie«. Iliuil condition. (Altcf Raihkc.l 
mCDt. (AtUrr llHllikL- i 

Of tlif rcrit/iM tiifi^em it has already been spph that there is a pair <if vitelline 
veins coming from the yoIk-«ac and owning into the venous *nd of thi- I'mbrvonioJ 
heart. In addition to tliej^e, other veins are develo[M'd at nn psuly jieriixl, vvhiehf 
unili' together and with the vilcllliie vein* before entering the hearl, tiimiing a| 
MTiKx rciiwtun. whieh later is taken op into the ripht auricle. Of lluhe vi-in« there 
iin-, tlrfit, the ntiil>ilie.id veiitH, uliieb lirinj' biiek the blood from I he )>laeeiita, enter- j 
ing the body ul' the embryo at the nmbiliciis {^'^S- '")■ ^'''^' '*^^'' KQihilieal veinf 




Fid. Itl.— I>«i«lnt>m«nt nf ni« THnu; .it.piimltlr* rnnillUiiii. )4lUtvml lymmctrr: B. tUrmMlon of itoiMl 
vntfio: Cilliia] omidlllnii: •tUitranniinni'. I.iliiiin vviiiitu>i: Z riicM rliictiii ciivIitI; '!', IcItduFliw I'uvlcri:!. 
rildn JUBuW tvln : 7. ten Jutnitnr irin ; 4. nrrlltml Hln . f. Venn aiTEni majiir: .V tltrllim' wlii. A. iiinbillral 
vela: «^ umbilical win in cnnl : 7. hiiUI vein: 8, liver: l>. iliiriiia venuui , li). Venn rnv» Inlcri'ir: U,rijmii»in 
niac vnin: lit, i-viia Ii«iii!*ityii(jii : la, l«fl l>rK(hiu-riiilia1lr vi'tii : II. c<iriiiiat!t •lnii>: 15. vcUu ot lover Umba. 
Atni|ihti^i1 rafl" '1 lirokvii lliicfc. iTiilul.i 

di-pi-nenites Infer jilinost i-nlin-lv, but the rifjlit p!tt*se.-i forwaril in the ventral laid- 
line of the iibdomiri to llii- luidiT ,«nrf;iee of the liver, to wliieli it distrlbnte.-* bbHtd, 
eoTitiniiing onwiini. Iiowever, li> ojji-ii into the ^inns v<'nosii>. Ihii'iii); embryonic 
life tbi.-i Vein ini'ri;i.-«r>< in r<\xi; the vitelline veiiw, on llie fither hiind, beeomlng 
fimaller and, fonnini: ennneetions with one another, eventually jriving rise to the 
portal vein. After birth, however, a.* .*oon a>' the plaeental eireulation cea*es, the 



THE DIAPHRAGM. 



97 



mnbilical vein becomes coiivertMl into a Milid cord nf tt^iw, which, from the 
tnu)Aveni« fi.>Han> of the liver lo the uiiibilitriLi, m known a» ih« round liffameid, 
while (Ik portion above thU ltecoin<« th*^ iluduu renosuji, the njipermoAt jkart 
IXTsi^ting ail Ihe uj)|)er jiart of the rata caca inferior and n-o-iving; the liepatio 
vwnii. 

Seeondly, there are two other pairs of veins whii?li are entirely nonfined to tlie 
enii)ry(y^thi^ jiitju/arn, wjiich bring luek to tlie heart the blood from tlR> head anil 
oppcr extremity, and the irirtihtali, which return tJic blood from tiic trunk and 
lower litob, the juf^nluni and cnrdinalx of each side of the bixly uniting to^-lher 
before opening inU> the ^inu^ venoMiK to forai a tranevervc brunch, tlie liuftw 
Clurwi-i. A« the embryo develojw tIk- jiigidai^ increai^e in fize moiv nipidly than 
till* i^inlirHd". «) that Ihc Cuviertaii dmn." seem to be the oontiniiatioiir^ of thi^ j"K"- 
lari>; utnl whrn (he sinii)' veniwus \> liikeii up iiiln I lie right auricle the two (.'iivior- 
tan ftuctn and the nnibili<-«l vein, wUieh ojtfn into the :siiius from the r'ljrhl and 
left »Ji)e< and from below, iy-.M)eetively, eoim- to have »vj)urale om-ning^ into tlie 
auritde, fonnitig the tlirei^ jirincipal ojienings found in the adult. 

The eunlinal veiuit do not, however, iH-i'sisI until adtitt life in their original 
condition, bill an- to a eertaiu extent reiilaecd by an unjuiired venous trunk, the 
rritn rttra ia/irior, wliieh niakes iin apj>earaiice iu llu' li-iHue bclwt-eu the twti primi- 
tive kidneys, and early unites with the caitlinal-* hv meau!^ of transver^w bmnehes, 
through M-hieh it reeeives the blood from the kidnevii ami rapidly increases in 
^ize. In the mean time, a eonnecting trunk lian fornxKl between the lef) und 
right eurdtnaU, and the main ma-iM of the blood from the lef^ lower limb lIowK over 
into the right uirdtiial, wluch tlini; becomes enlai^:ed and formi? apparently the 
e>»iiinualion of the inferior vena cava. Al>ove, the vena cava owns into the 
umbiliral vein, and, on the degeneration of the umbilind atW birth, tin-? Up}>er- 
nuti-t part "if it |>ersint< ux the upjier end of the vena eiiva. Thi« vi-^'^el is, there- 
fore, emniMM-t) of thnn- originally dibtiuet imru: (I) thv indeiwndent trunk 
between the primitive kidiieyn; (2) the lower end of the right eunliiial vein; 
and {-i) tile uppernn»t jKirt "f the unibilical. When eompletely formed it ri'ecivw 
the bliHKl fmm tlie (•renter part of the territory originally (Irtiinetl by the cardi- 
nals, the upiM-r |Hirtii>nN of ihiT.e latter still conliniiiiig, however, ii> receive the 
bloix) fn>m till' intercostal .'•|iaces of the thonix. Tin- lower ]iart of the h-ft or- 
dinal eompletely di^)i[>ear:«, am) it at^) loses its eoniut'liim with the left (hietu.'t 
Cuvieri, forming instead a Iransverflc connection with the right eanlinal, and 
becoming the rrit't lirmiaziif/oH (a/ygw* minor) of adult analoiny, i1m> upper ]Mrt 
of the right cardinal becoming the eesw nzi/yos tnnjor. 

In the mean time, a >(light change has taken plaee in the jugulars, a branch 
piwung acnies from the left to the riglif, and forming the trfi limc}iio-rrjthatic ivin 
of tlie adnll. which n'ceives and [Kisses over to the ri^hi jugular all the blood 
returning by the leA jugular. A^ the result of this the [xirllon of the letY jugular 
birtwivn (he origin of the left braehio-ceplml i« vein and the left duetuis Cuvieri Iw- 
eonies grvally refbicwl. being n'present<il iu the adult only by the ^iirnall ohIi'|iie vein 
nathi^tiaek of the leflaiiriele; but the left liiictn* Cuvieri. llius ''i-})iinilc'd from both 
the jugular and the earrlinal vein which origiunlly opened into il,iii>(-s not degi^n- 
emtc. liinoe it j-iill receives a liirgi- prii[Kirlioo of the IiIixhI i-etuniing from the tissue 
of the heart itself tlin>ugh ihi* eiu'onai'y veins, but persist.* a^ tlie eomnary sinus. 



The Diaphragm. 

Clit'^Iy 8-^MK-tated with the devpIo)imenl of the venous Ininks is the formalion 
of the diaphragm. At first tlieljody-cavityorco'lom is a eonliunous cavity extend- 
ing the entire length of the trunk, and even into the licad region : but dnnug 
di-velopnient ilw jMirtion; in the head and ne<'k di^p)iear, the thomcie and 
alidominal [H)riions |KT$i«ting. and being at lirst eontinuoi»t. After the be^iri 
has formed, however, a tliiok tmn>fver«c |)artilioii, the ^rjitiim triinfvnmm, begins 
to gn>vi- from the ventml and latcrut walu of the body trtnanl the Hinii^ venwus, 
T 



m 



EMBRYOLOGY. 



pnoloi^inf; flw- venous tniiik* wliidi otK-n into tlic «iin». By its lorruation the' 
ilic.rarii' iiiiil iiliiliiruiiml {ini-tiiuin ttf (\w rivinni arc almui't complclcly !M-|)nniiPcl, 
llic duly ('iiiniiiiujiiacioii l)('tw<:T-ri iIk'Di Win^ l>y n juiir <it' nmiill ninal'liku open- ^ 
inp*, one on cacli siiif of iIk- dorsal moM-nici^' ; mid, as ilif liiiiff dovi-lop, llicy ^B 
[Hi-li ilu- walls uf tiif ranals in trout of iliem, tnesc walU tliiis IViniiirig tin- pk-unc. 
Al a tonijiaralively early stage of development llu- |>ericardial pi>rlion nf (lie 
Tliciraeie eavity heeomes s-eparated fi-oni the pleural jMirtion.i ; and consiiii-RibK' 
Inter the hitter become eiit oH' fwm the ubdontinal cavilv, then Unown «.■« tliA 
IsritoTieal ravity. by the jrrowth furwanl fmm the doival wall of the body of a 
partition whioJi unites with the five edgi:- of the ^eptum transverstnn. 

The Lymphatic Vessels, the Spleen, and the Suprarenal Capsules. 

Of the development of the /ifnijiliiidr rrnKf//i companitivelv little is known wilh 
t^lrtsinty. thoU(fli they (ieeni to be funned similarly !■■ the blnod-veiwels by a hol- 
lowing out K'f stniTids of nu-KeiK-liymatoni^ eells. The nimle of development of 
(he Kjif'vii t!i aUo biti iiii^K-rfectly kimwii : it nrises ii* a eollwtion of me«>nehyina- 
lons eells ."itimtMl between ihi' Invers of llie ilui>a1 luescnlcry of the titonmeh, and 
earlv reeeivet* a rieh T.up)i!y of bfood-\e.isels. 

Yho KHpramiaf hndifs are formed from certain tubules of the mesonephmn 
(m-c below), a rieb nerve-snpply from the abdominal portion of the fiym]Mitlieti<: 
cvjilem Inter pi-nctniting into llie tif^iie. Ar(VMi>r;i int/ir'Trnnfi; aUo known aa 
.ifiiri'/idiiiri' iiilrrnitlK, iK'eiir in the bnmd ligament of the fi'mali- nod flic spennaiio 
cord of the male, and an* also formed from snme tnbnlei* of the mes^mephros. 

The Musctilar System. 

From the me^otbelial poninns of the mesoilcrm the vobmtary milsc-tes and 
the urino-genital >i'Mein ilrvdnp. The volunlnn noiielrs arc derived fi-om the 
mesodermal somites, the gii.iiler portions of wbicti become tninsformed inio mns- 
cie-lis.-iie, !in<l.eonsi<]ncntly. the vobnilary niii-scnliititre has primarily a M-gnicntal 
amingi'mcnt, eonsisltng vf a series of mnM-!e- plates plaekfl one behind tlw other 
on eaeli side of tlie liojiy, and extending furwaiil even into the la-nd-n-giou of th« 
embryo. Kach plale i> sijpplieil bv a er.niial nr ii sptoal nenc, and has the fdircH 
of whieli il is composed direeied longitudinally, and arising fmm and inwrtwl 
into the eoIUlel■^ive-li^^ue mi'nibi-am-.- wliieb se|Kiralc eaeh jiair nf plates. This 

firimilive arrangement, however, is not long ntained, the varifius mn->ete-tilale» 
iifling together to a greater or less extent, and dividing longitudinally and into 
various layers, and so producing the eomplieatcd musenlar system of ihe adult. 
The involuntary mn-ele-lissne whieh oeenrs di>-iribuleil ihnnigh the walls of 
the various viscera seems to arise by the difiereutiatiou of nu'senebyniatouii cvll^, 
and to have nothing to do with the niesutlormal sumiteii, 



The Excretory and Reprodoctive Org^ans. 

The excretory and reprocbietive sy.siems arise fn>m oertnin of the mesoilermal 
somites jusi where they join the splanehnie and soniati<' layers, and the first ]Hjr- 
lion of the exerelorv system to iipjiiar arises from eerrain somites in the vicinity 
of I he hcurl, a ■-I'liil eord nf cells gli>wing out I'rom eaeh somite toward the ecto- 
dtTm, Ivieh eord later become* converted int" a eaiial, whieh opens al one end 
Into the ecelom, and is eonncrled at the other end with the eetotlerm. ThiB col- 
lection of tubules is termed tlie /imn'-/)fii'0» i Fig. 1 1 2), and as it develops then? is 
fonned from the eeloderm, along the line when- llic tubules ur<' in contact with it, 
a longilndinal eanul. which l;iii-r >cp!inites from the ectoderm and eomes to li<> 
eloM- to the nie»oderm { Fig. Iilll. This is llii' y«-fif"7(A/-iV or H'o/^iiiii ■/'/''/. with 
whieh the tubules of the ]in»ncphn>s unite, and whirJi o|>on!i. ptisU'riorly into the 
urogi'uital siniif'r to be describtil later. 



TIIK EXCRETORY A.\D REPRODVCrrVE OttOAAV. 



99 



The [»rone)>1m^, liowwcr, is liut u tninsitury ori»nii, iintl it wmit (U'^i-iu-nttcH ; ii 
DDtl cxcrvlory <ir^uii, tlic tHfmnrjihnm i)i' IIVi/AViit hrxtii, ntnVvf- \\.f- H|>jH^iraMO<*, JU 
pwlopnit'iil Itr-in^ similar tn lluit nl' the [)riin(-|ilir>is. Its itiI)iiI<-s, whii-li ii[M-ti nl 
one end into the o<i-li>iii nml nt iho olhor itiin ilic Wolfliuii iliu-i, n-:ti-lt :i (imsidcr- 



otOKimiius o> vHOHOHaoa. 



pKejtcmAov- 



USCTIB 




Fio. 11*— lirnEmn of iho Tsrloo* txatUiTf anmta ni(<nfalvclr itfTcloiicd tn tbo tbmiMlon of the iiilnarT 
•jtun. iTmut. I 



^ 



ahli- IciiKfh, iiiul lK-ii)iiif tniicl) coiilortcd, nn<l n knoi of mpilltirv h]<)<KUvi.-:!wvIii, 
" vi-I'ipiiifi ill (i>ii(iii'( witli incli liiimlc. |m-hc* its will iii Irimt ul' it to rurni ti 
'gloiMrruluK )in>j<-nii)i: iiiKi llic liilmlf. 'I'hi' liil)itli-s i':!?!)' Uwi- iln-ir cuiiiK-i'tioii 
wilh the wcloin, ana, Ihoiigh at lirsi lUoy iiwsoiu n striotlv segnioiiI.il arrange* 
nu>nt, tins h not a(lh«?r«l t<i, as sciiniiliiry ami ternary tiihiiles ari^i- from eiwJi 
lupsodfnnal Hninitc, clevel(i|> fflnmortili, :iii<l unite will) the primiirv tubtite-i to 
n inio tiw Wolffian tiiiet. TIu' Wolffian ImmIv llui« l>cf(inies an oxi-cidingly 
im(ili(ittMl orjpin, wliicli, im a<v(itint of its Mr.c, t'oniifi a strung projt-i'tion into 
tbt' weloni fnnn tin- ilorwil wnll of tlio iMxiy. 

Bnt vvvn liiiK sccomi kiilniy iIikk tio( jMroir^t into adult llfv a^ a fnnctioiiit) 

rrvttirj- nrgnn. I>nl jMiriions of it dcgi'ntnite. wliiU- other (Kirts ari' lulapted to 

w fum'tions, iln cxcn-tory fniii'tionii bi-inp iis^nnu-d l>y ii new kidm-y, the mrfrt- 

'phrui. This uii[M'!iiM Jis II liihiiliir i'n()ir*twlli from the dursiil ■•iirfiice nf the 

'W<-r |nirt of titch W'ollliaii iliifl, iinil fi'ciiii iht- iiiilerior end ii( this a niirnlM-r of 

hnh-s grow out and |iii-'li llii'ir wiiv into a nins.'s of niesiHliTiuiil tis-'iK- uliivh \vMt 

riniH-ntrat<Hl aroniul llnin. Tin- original oulgi^iwllis iuHiinn- the "nitrit, and itie 

:ihul(-.-<, which bci-oine very niimeivms, develoji into the nrinni-i/ tuhtJin, in ioiukv- 

twd wilh whieh .(//tfuici-iJ/ (Malpigliiaii mrpiisili-s), derived from the mesodermal 

iijfls*!, develop. The mmiHiKt organ thus fornieil beeomes the Ametional ki<)ney M" 

the udiili. 

When the Wolffian IkhUps !irc fully ikviloppd a cord of pc11« up])ears on the 
leral "iirfiipe of encti of llii'ni, and lMT">nii> eonverted into a csuial ojicning 
h"himl int<t the iIoikh and in fninl int" iIil- c<elnm. This is the Mullii-iim thiH, 
by tlic lime it is islublihln il a thielienitig of the pi'ritoneal <vlU eovering the 
ial (iiirt«oi'» of etwli WoUIiati Ixnly Hp|H'»r<t, forming the yaminal ritiyrii,inm 
the nviiries or te'trs ilevdop. In ilii' i-a-i- of the orarirn the inesi-nehvma- 



100 



EMJlItYOLOGY. 



tons tissue immwIiaU'ly Wuwith t)je thickruiiign dcveloji iiilo 
which cords o{ cell.* (Pij;. 113) grow from the Ihiokeiiing. C( 



ihe strnitia, into' 
ertain of lh« cellb 



tPITHEk'UH 



ctrno ot cf Li* 



FRIVJTIVC OVULC* 
IN (MTKCUUH 




TO •t>tll«T( 



raLueu i 

Pin. IIS.— Snrtlon of Iha orary of ■ nc w -born rhlld. (ARM Waldcj'n.i 

iif llif nm!-' I'tilarp- gnatlynnil Iktihhp ova, the rcniaiiiilip cc]U miiltiplyiog rnp- 
iilly bv (livisinii ami IdWirniiip tlic l'ollicli'-<;clli-. Division uf llic cells which are lo 
form n\Ti iiopaira lo «*Ji«' at nboiil thv wccmil y«ir after birtli, bv which tinip, 
theri'fort-, alt the ovh lire flifTcronriiitc-d. The if/irM an- nt firwt very Mniilar to the 
*i\'aries, iind havi- ii ^iiiiiliir <l('Vi-l<>|iiticiit, ihe fiieriiintic (■(■il!< being <lmvwl frum 
thi- eells lit' the gtriiiiiial ridp*. iiiid the ^Irnriin uf ihe wvury bt-ing rejuvK-iilod by 
ihe tuiiiea ulbiigiiiea ami llio ti-.ibeciil.t' uf tlm re.Hii«. 

When miituri- the ova an- cxtriuliil fmrn ihc ()vurv [iracticullv ti)t<> the jhti- 
loiK-al oavity, thoiijrh, ji> a iiiiillcr of fuc-l, ibiy arc iisiially rcicivi-il at mire into 
funni^l-like o[>(.'i)iii^ by wliioh liie Miillcriati (Jiiels <tiiiimiiriiriite willi lln- |HTi- 
toneal cavity, these ditets iHeominj: the Fii/lo/jititi tulitx of lln- inhih, and tht-ir 
lower |R>rtinns fusing to fonn the iiterux and rof/iuii. In liie enihrvo, however, 
the Miilterian duets extend mueh farther forward llian tlie jHwilioii <if the ovary, 
the oi^tiiiin of the Faliojiiail tuWs Wing a new fonuMiion and mil ihe origintil 
terminal opening, the mon? anterior ptirlioii of eaeh duet iH'iiig imibably rejire- 
»enU'd in the adult by the hiitlaflrl cif Morgtifpii (Fig. 114), a pumll vesicular 
i^IriK-miT- uttaelKil to one of the fimbriw of the seeondan,' ojiening. While the 
ovary :ind the nielaueiihros have been deviloninp the mesiuu|ilinis has been 
degenerating, ami all tliow jiortioDx of the Wolilinn duets which lie anterior to 
the points of outgniwlli of rhe niel;ii)i-T>lirie ihicis disapjuar, exeejit small portions 
at i.^neh eiiii. The U]j|ii-r end, (hrougli uiesoiteiilirie luludes whieh eoinniniiieste 
with it, (■<)me>^ iuto intimate relation with the ov»ry, funning with its tuhulm the 
jttiriiriirliun, winch in the adult lies eloi* to ihe ovary in the Hub,*tauce of the 
IirmhI ligament. The lower ends of the Wolffian duets persi.-*t ns the etiiiaJt of 
(iiiiiiirr, situated on eaeh side of the upper end of the vajriua, while the inevw 
nephros almost eomplelely disinpears. il-. U]>permost tubule!, just mentioned and 
u shiall portion of its lower end alone jiernisting, the latter forming a eyst-like struc- 
ture lying between the layers of the broad lij^itnieut, and termetl the paroijjilioroti. 

It has been weu thai the ovaries appear at the level of the mesonephros — 
that is to ray, well forward in the alvdomiual wall. This position, however, is 
not retainiil. but ihey deiweud iw development proceeds, and finally lie in the 
|«elvic cnvity. This descent i.^ (wrlly pnuhieed by the eonlnietion of a baud of 
C'onnet-live lis.'«ue whieh deseemis from the lower end of the mesonephros to be 
attached to the ;*kin tn the n-gion whewt ihc labia niajora will later appear, and 
wliich i.t represented by the round tigauwtit of tlie udull. 



I 



THE EXCa£TOBY AXD BEPROJiUCTIVE ORGAX.'i. 



101 



Tbe U'«t4.><^ and the pan» in tlieir nclgliborliood nndcr^co chitiigc-ii com pa rail It; 
to tboM jUF't dcr^TJlK'tl fur llic ovuries, ilic |iriii<.'i]ml dill'LTciK-e being lluit th« 
Hull«Tiuii diicU <k-gi-itcn>u- i-xvept at their two exiremitie!', the anterior eiicU [ter- 
sistini; ils » ^mnll vi^ivlv iiltiK-heil t<> vavh epiiiklymi^, mid known a» Uic /it/tltiliit 
of tlu fjiiiliiii/ouM, while itw* Iwwer omiw unite tuftelhir to ioriii a &niull siie, whi<!li 
uj>cn!> iul<» till- iiixwliitif [H>rtii>n uf iht? iir<'lhni, and i* termed the si'ijhh [lorulnriit. 
This lutt(;r ittrm-tun- frnm ttM iniido of furmiiliiin U evidently Iiomoltigoii^i witii 
tin* iilf^riH of thtt feiuult^, and ha-^i (■on!«<H|ti«ii(ly liren li'mnil ihe utrrug uuttt^tflittus. 
On tiii> rttiier hand, thf Wniftiaa du<-ls |k-mi»i, forniici); the rtuot ilrfrrnUin, and, as 
in the fcjiiale, die tubules of ihti upwr portions of <^nch Wolfliuii body pmvr 
inward towanl tlie tcstai, with whieh tney unite, their ti?>tieubir eiKl.-< litrniin^ the 
Inhnli recti and rtte teidi», while the ends conuecte<) with thi- Wolffian dueti> form 
the rpiilUti/mii, The reraaintter of the Wolffian fMHiien undei^nes abiKK't eomj)li-I« 
degeneration, jmrtions, iMfWever, an in tbe female, persiuliiig, anil fomiiiij' tlw: 
Htnietures kuou-n as the ruhi aben-aniia of ibe cpidtdyiuis and the paradCijimui 
or organ of Giraldig, 







H HfllXH* 



mtmmtut 






rCMALE INDIFFCRCNT MALC 

TlO. IN.— ningrkin at thp ilccctopmcriit at ihi vvn no- urinary apponlun. <3tiHUllril from Htixlff-) 

The roMiid ligaraent, whose eonlraetion oeejuiions the- dwwnt of th^ ovary 
into th* i>i'lvip oavity, Hincc it is primnrily in conncetion with iho mfttoncphros, 
hu naluraUy » rt^prewentiilive in the niale, |ms^in)j fmiii tin- lower end of the 
m«!Minephrofl to that reg:ion of the skin where the wnttnin will di>veloi». By it* 
eontraelion the deseent of the tejiti^- is broofrht :ib<>iH, this orj;j»n bi-inj; drawn firift 
into the cavity of tlie false |jclvii-, and ibeii into the in|>;ninal rojiion. Here, in 
the mean time, on eaeh side, ii downurowlli of a finprr-like process of periluiieilin 
into the serotiim by the f'ulv of tho rimnd ligninenl has oeenrred, the downp;n>wth 
Iieinft pn-i-t-iled by pnOoit^lions of varioiiH mnseidar layers of the iitxlominal 
wsll. The te«tw, oontinuinf: ihoir ileseent, ndlow lhe>M? pontoneal downgrowtlw, 
and ihii* eoine lo lie within the serotuni, the |)eriloneal pn)ce«ee)' wmppiitu them- 
^I'lvo amttinl llu'in and forininj; the tniiicft rn'/i'jirt/f*, the ne<'k by wliidi the pnieeas 
mntniunii'ntf.i with the general peritoneal cavity snbwcjnentiy eloping by the fiL-iion 
of Uk wa\h, while tlie remaining coverings of the t«tttvi> arc produced by tbe 




102 



EMBRYOLOGY. 



miiNrlc- iinii fiwin-IiivfTii of tlic iilxloitiiniil wnlls wliirh prt'Wilcct tho peritoneal 
|inii'i'ss. 'I'lir I'onl, \»liii-li ivjirc-ni'iils tin- niiiml H^iinrnt, i> U> Ijl- liniud iti the 
adult in u nmnlt ctirtt vvhirh |>a!U^e.H from tli(^ epididymis to ihv wnll uf iho ecrotum, 
ami is Icriiied \\»- guberiMeuluin. b 

It har' alrciidy been atated that the allaiituin does not tiitin*ly dififiH-ratp utfl 
birth, the miiiiile purl of \t^ iiitniH^'ndjryijnif itoi-iiui) }HTni>liiij^ iw lln- uriniirtf 
hi'ii'lilvr, and the |Kirt brtwifn this siiiii the umniliciih hceiiminj; winvi-rti-il iiitu a 
solid fitrd, kiinwn sic the ii<-iirliii.i. Thi- (Kirl bitnwn ihe hlad<l( r and rht- inU-A- 
tiiii- Inniis what is tinned llie unufntital k'hiiih, atid into it the Miillenan and 
WoHtmii dnclP o|M.*n. In tin- develnprnfnt of the Hrefrm the jmrtions of llie 
Wohltan dni'Is hetwi'en their [Hiint iif iirifrin and llie tiniis are, in (lie niale, 
graihijilly taken up int>i the siims, wi tlmt lln- iiretei> and the vasa delen-mia 
imve sepaiiile oiM-nin^p-, the li.rnier uni!ln|: *\itli the hiv-v of (lie bladder, while 
the latter oihhi into the -inii.-. Sinee the ullaninis i» enrinertcd with the inies- 
lino, that portion of ibe digestive tract n-eeive.- lln- nriiuuy ;ind genital pn>ducta 
aa well as the fa*es, and tlins reedves the name of llie r/'mcii (Kig. 115j. At aa 
early iieriod this eloacvi beeoiiies di- 
vided by u purtitiou into a <lor<al und 
H ventnil portion; thU partition beoom- 



1 







-OlfttTAL rOLD 
CINITHI. lUDIlOW 



FicIISl— Kilcctuilrli-wofllioolwOT. (UnitwlK.t Flo. 11«,— AnUgtor the iwnliuroniorto. (IIertWt») 

Hifl pnidimlly thteker, the dorwil jwrtion, repi-e-eiiliiit; thi> lowermost jiart nf the 
reeliini. lieeomes wpafsileil from the venlnil portion, the iv^rion inieneniug 
lK-l\vi'eii the two lieing the {iri-iiiriaii. (Fig, 117). 

Ill llie me-an time, however, on each Mi- of llie urogenital opening a ridge of 
skin, lh« nnlage of (he scrotum in the male and the labia majora of the female, 
has apjK-ared, ami botwei^n tlie anterior (ventral) endn of the ridges u tnbeixrle 
develops, ahmg whose [Kislerior ■■iirfiiei- a groove is formed whleli opens pnixi- 
mally inl<i the nrogenitjil ^iiins. 'Ibis uilKliIe is the aidago of the i>niiit or 
rtitfiiiM (Kif;. I Hi), and at tlii> t-liige ihire i.- |niietie!dly no difference U-tween the 
male and female genitalia. In ihe male the lipf^ of the iK-nisI groove now imt-t 
together and fuse, tho gruove beiiij; tliereby eonverleil into « «uial eontiiinoiiH 
with the im)£renital rfniw, the lanal and siniits together eonslituling what is 




'[■iincuH 



Fifi. 1i;.— Fonimtiutiof tho jiorlncun), KporatlnK 
th« ■llnivnunr iiml i\w i;L'nili>-iitliiiu'y tMUtwcc*. 
lUcrtwlKl 




lllpnalfc; 



«!.*•■■ NNIS 
01HITJL1. FOLD 

(HiKL ruitnow 



ECHO TU HI 



I iiri'llitB Knd (crotua. 



termed the vi-fthm nf the adult. Ac a rr-snlt of this elosnre of the groove 
the senital ridges* of either side are brought into eonlact, and fuM- top-lher 
below the penis to form the adult wr-rfiirn (Fig. 118). In the female the lipa 




ORGAA'S DERIVED SJiO-V THE ECyODEliJf. 



103 



of th* KToovt «iJ tlip clitorN do not fiist-, Imii bpcnnip grcaily cnlai'ttiKl and 
form tltL- Inhin miiftrti, and tin- lohla mnjoi-a rctn^iili }^|)ai':it«'<) liv ii tle|treni>ii>n 
into wliirli the iin-thni. ilovclopeil in lhi>» ciise from the uru^'niuil niiufi alone, 
uhI tlic rvjf/iiKt u|MMi (Fig. 119). Tlie final arr»ngvnii>nt of tlii' tciunlc extprnnl 




iniTiii. niEMii 
IKITll rokO 
or vnciHii 

nova 




■luB ■inus 

or viGiNa 



fvt, IIVl— )>cTci4iiDcni at tmId*. (Hertwlc-) 



FKt l;il —liMTlt-iKnt'iit i>[ lilt' IViaBlT utknidMnl' 
nil. (Hvnulg.l 



genilflliii miiv llin« W rcn'lilv comjHirri} with im t-iirtv .'^1»p.- of i1(-vi-lci|iiiir'iii of (he 
ra&le iii^.in*, the lattt-r undergoing a grtiiU-r uinouiit of diflVn-ntiuliuti lliiii) ihuiw 
of ihc ftinnlp. 



•POMOt»aut«T 



ORQANS DERIVED FROM THE ECTODERM. 

Of the entoderm th<- (l(-rivaiiv(>!i are ihf ounr liiv('r- of the i^ltin and its 
njtficndnj^-H — ImifN. naiU, Hndori|MirmiA, ^^baccoifi, and mnminiiry ;;lantlii — and 
tlif iRTvous system and senije-organs. Of the formiT a dt-lailcd account is 
iinnpcessar)' herp, but (he nnrvoiun system rprniirc- due consideration. 

The Nervous Syst«m. 

An has been fteen, th^^ ci-nlmt ncrvouH svstem make-t it« apjicaninoc a^ the 
niMliillar^- groove. \^ divi-lopnii-nr ])rocei-(iii [lie li]m of the grinive ^nidually 
ci>mp to^ietlicr, and cveniiwlly liisp, transforming the groove into the luedallarjr 
canal, broader in front than 
Ui-hind, and ninning the entire 
letifi^h of the Iwdy. The cavity 
of iIk- cuiial Ix-coiucsi the iviitmt 
eanni nf the n/iiniil tiinl gtiid the 
w/i/ri'o/fj* itf llu" liriiin, whitf it» 
walls JH-come oonverle^l ititoihi? 
varimis pann of the <M<ntrul 
nervoiiH system. 

At first tlie cells eom|M»siiig 
tile walU of the nnial are prao- 
licidly similar, hut later certain 
of them, the imii-'Miintji, Iving 
nearer tlR- central can.'d, licgin 
Ut proliferate ra|>i<l]v, I'.irmwij; 
nfrrr.rfHi- (Fig. 12])'. wWiV- (he 
remainder, llir aiumriiiJihmfK, 
waiter theinsilvt-s iiiii'itm; the 
nervc-^fll:" and iK-eimn- the 
ueymi/tia, some of them cveiilnally eomiiig to lim^ llic ecntnil iiiiial and frirming 
tJ»e riitfAi/ma («n/yui"). The walls of the ('anal aUo hcL-nnii- of nuc<|iiiil thick- 
ness, the |)ortionH in the doi^^l and ventral mid-lines becoming thin and forming 




»0UNO 
nlVHOBua 



ft*«xaioBt'«' 

NEI>II0«L1*T 



Pill. Ill, —fill vi-liiiimfni "f nvTvp-rvUt mul nmrotHaetna In 
wall orOiD mi'iliillnr]' cnnnl. IThIuI nnj llii.i 



104 



EAfBR YOZ.OO ¥. 



rwiK'clivoIy ihe yoof-plate and the Jfoor-nlatt-y wliile each of the lateral Uiicker por- j 
Uoiis bccfinifis (livided h_v a loiigitiuliniil gmovc into Ji floi-ia! ami !i fcuiral tonr. 
[The iipiual cord develojw from the nairowtT |K>*UTiiir [wrlii'ii of the tut-iltillan' 
al, antl ir^ formed mainly by tlie growth of the celU of tlie venlnd zoiitit. ilie 
dorsnl Ronea being reprewnted uiily by the dorsil horiitf of file gray mutter. 



while the part* contributed by tJie roof- nnd fltior-jduteis are eiiiniMinilively in»ig- 
ni6c:int. At an cqirly period a series of ennxtrh'lions, Kepiinitod frimi one another 
by definite inlervtiU, iiiii>i-jir iliroiifiliout its eiilire length, and give it the u]ipt-nr- 



n 



anee of W-ing euiiiponeil of a series of •icgmonts, whioh an- termed utiinnim-iv, and 
to each of wliieii a pair of iutvi^ corrc-pondn. The cxinteiiee of the eonstrieiiona 
\», however, tninsitnry, and it is probable that their appt-araiiee it* rilaled lo tJiK 
ocoiirrenee of the mewKk'rmal somites. 

Up to (he end of the third month the eord is practieally aw long as the , 
»ninal eanal, but later the ejinid j;""'*''^ '" lenjjtli more ninidlv than the eord, so 
tliat the latter beeonies relatively cliorter, thoujrli aelnaily it elongates. As r ' 
rc6u)t of this imeiinal growtli, tlie iiervi-i wlijih [mw out between the lower 
vertebra? miijit lenglhi-n, and wi the biiiieli of iiervi's termed the iitmlit nittinet is 
formeil. Tb« nuit'tr urrrrx nriw from o-IIn siinnU'd in llie verilrul horn of the 
cord, and grow unl toward the mtit<cle^ for which ijiey an- declined ; the Ht-tumrg 
nervf«y however, arise fnim a series nf thiekenings silunled ju>t external to llie 
lips of the nifdnllary groove, which, on the i-loMire of the grfH(\'e, xe|>arate fnvni 
Iho ccto<!erm and sink down into the mesoderm. Fnmi e.ioh <'i'll of ilie,'«e thiek- . 
enings, whieii are the d</r»ul rtiuf-f/nuf/liit, Iwn processes are sent oft", one of ' 
whieh wnctrates the tiubstance of the eord, while the other extends [>eriphe rally. 
There is thus a fiimlamenud <li»tiiK'ti'>n between the motor and the sensory nerve- 
fibres, the former always growing out from the eenti-al system, while the latter 
arise externally to the eord and brain, and grow inward toward them. 

In the anterior portion of the niednlhin' eiinul, from whieh the brain develops, 

neuronieres are present as in the eord : hut, 
in addition, two nxire dislinetly marked con- 
slrietiotis up[K-tir aii<l divi<le the brain info 
tlirei' priniiiry ve>iele». The nxtf-idate of 
the miMt piKterior vwieU- fomiit ii tnin roof 
to the eavilyof the vesirU'(Fig. 122), whieh 
broaden." out to form the jimHli rmfni'/r, a 
transverse ihiekening, however, developing 
in the more anterior part of the n^if, and 
later enlaiTriilg to form the rtrrMliitit. In 
the posterW part of the vesicle the dni»al 
and ventral tones become well developed, 
forming the medulla of/hnr/ata, while ante- 
riorly fibres grow downward on each side 
from the cerebellum toward the ventral 
mid-line, forniinfr the/xm/i. In ci>nsequenc«, 
it i» ni''ti)mary to regard the third vesicle as 
being seeondnrily <livi<led into two vef^icles, 
[he ]Kisterior of which ix termed the aller- 
hrain, or mtieiierpfmlfm (niyeleiieephalon), 
while the anterior, whieh includes the va-k- 
hellum ami (kid.-, is known an the hind- 
brain, or cpetiitfjiti/on. 

The cavity of the middle vesicle does 
not increase in she as rapidly as the others, 
hut invunie? the form of a canal, and is 
termed the llrr or (iftinlurt. The roof-plate 
retains its pritnitive slit;ht devehiunicnt, the 
dorsal zones, however, giving ritte to four weli-ninrked tliiekcningfi, tnc mrtMra 




VM. ML— DIM**** ot lt>* bralD Hi an etiily 
ttia<iitti«viHeotatiU- /,rHvllif i>r |>rliiiiiry |>ni>- 
mrvphHlnn ; (I, r^uvliy cif inc-b<ta.^i'f.li«1<}ii - 17/, 
cniliy .if flprni'eTpfiril.in : .If. mi'lll.ny i>11i (Y", 
<N'ljl'*1 fanul of i|>lTEii] <'i>nl: I'K^ crrvbclluin: 
CAT, !■ nil 11 I'l-rrtif! hikI niuilrfin-iiiiiiii ; iT.n-ir- 
lif«l t»»li>U' , fV), ftimiiii'ii ill iliiiini: ll'i, mc- 
rtiilln Dliii.nKntii. "I„ olOn'iff): l-ht: iifT V.. 
oWlo T«Vle; SF, tyinaX CoM; TH, Ihalnioui 



THE XERVOUS SYSTEM. 



105 



CHOHOIB 

ronkMCH 

or MOOHO 
<AVOILTC' 

NUCLtUa 




rouKf** 

VCHTAIGlC 



imrunDiBucuM 



Flo. m— BtkId o( tnbryn. (tdf view. itllhslrorkLI 



iritfeminn, whilp thr ventral y.cinc-t \vrnnw iiiiHlili'^fl tn form the erura cfrebri, 
I thi- difiercnciaiwi luwldle vftiide i^ givfii iIh- name uf ihc njid-braiii, or mewn- 
(Y/zArt/on (Fig. 12:t). 

The anterior vesicle iindei^ 
I goes greater channel; than either 
of the othenc. l-in^t, from the 
lower |uirt of ItK luter.il v/nWn 
two porifht* uniw <Hit. tiiiiilly 
ciiin*' into ci>niael with ihi- wtu- 
dertH of th<' M(lw of tho ht-urf, 
UDil forti) the optir ve^io lt> { Kig. 
122), iind inter n mnMriclioi) of 
till' origfinal wall of the vesicle 
aiip<-:trs, the v«>iele thiw bewini- 
in|£ divided into two pirtions, the 
anterior of which, growiiig most mpidly on each side of the median Iiim?, eventu- 
allr gix'eit rise to the cere&nil licniifrplicres, which are (o[;ellicr termed iin fvre- 
bmin, or proJKnirphahn, while the mL'<liHii portion, together with the entire 
Hosterior portion of the onKimil voifle, forms the 'iwirn-bnun, or tkalniatn- 
crphaian, which oontnins the fhlM rrn/riW/-. 

The wnti-rior wull of the ihinl ventricle w evidently, «in<v th<> heniiiiphcres are 
lsl«n1 ontgrowih^, llii' front wull of Ihc ]iriniilivf hrniii. and it ooti^tiliite^ the 
lanana Urtiuuit/iii of the aihill. The gn-Htcr iKirlioii of th« rimf of ihi- third 
ventl^ele Ix^come^ rediict'd (o » thin Inver of ccilx, which, together with the ])in, 
whioh lie* immediately ahov* it, forms the nlum tWi-r/wwi/itm, while more poste- 
riorly an <>Vitgination of the rm>f produces a stalk siirmoiint«i by a solitj oval 
bodv, the epiphiftin, or pineal IhkIv, which enrnparaiive aiiatonty shctwfi to he the 
rudiment of an nnpuired. median eye. In t)ie floor of the ventricle there is to 
Ik- found, in addition to thi- optic eitilks, a hollow,fiinnel-like downgrowth, the 
infundiftulum, which ends in a solid hody, the kitpopktinU, or pitnilarv body, 
fonned partly by a dilatation of the exlreroitv of the infundibulum, and partly 
by a mass of tissue which arises as an upgrowth from the roof of the mouth, from 
which it becomes separated ; and hiatly, in each of the lateral walls of the ven- 
tricle there is to be found an oval thickening, the 0]}ti<- l/mliimiii^ (I'lg- I2'2), 
developed from the dorKil zone, the subthalamic tii^ues ln-ing the product of 
the venlnd xonc-<. 

8int!c tlic c»;nrbnil hcmi»phcro« di-vclop as latend eularf^mcnt^ of the anterior 
of th« two necrtiKbiry jxirtion!; of tilt v<»icle, timl isinoc thin jjorlion contains a 
cavity (a pari of the Ihinl venlriele), it w dear that each hcmiNgihcri' will roiiluin 
a lateral prolongation of ihi* cjiviiy, a lolfrtil n-nlrieU, and thiit i-ach lateral ven- 
tricle will comnmnicjiU- with the nidc-s of the anterior end of ihc thir*l ventricle, 
this eommuniculion iM-iiii; the Joranun of Mmirii. Thi^ hemispheres arc, strictly 
speaking, excessive development'* of the dorsal zones of the anterior vesicle, and 
there occurs in the wall of each of them a thickening, termed the rorpus utriatum, 
which ifi continuous behind with the optic thalamus. As the hemi.spheres continue 
tu develop they project in front of the lamina tenninatis and overlap behind the 
roof and I'ldcs of the 'tween- and mid-brains : and the luteral ventricles, increas- 
inji in «!«■ jMri pfismi with the gn>wth of the hemispheres. iM-conie prtilonged into 
anicriiir, [wwterior, and lateral horns. Into the outer layers of the hemispheres 
an immigration of wlls occni*, the cerebral cortex being thus formed, aikI during 
the earlier nionthif of development division of thee cells occur" with eonsiderablc 
rapidity, gradually bi-eoining mrer, however, until some time Ih-IiiD* birtli, when 
it completely e<^a.vT-i, there Ix^ing, in all proliubility, no normal inerejL-'e in the 
numi>er of c»-Ils loniiiiig the otrrcbral cortex ailer birth. 

At about the fourth week of development a linger-like dilatation forms on 
the anterior part of the under surface of each cerebral heniis|>herc, a prolongation 
from the lateral ventricle of llie same side guissing into it. Anteriorly, the dila- 



106 



EMBRYOLOGY. 



CCIItBILUfM 




OLrACTOD* 

uamt. 



Fin. 114.— Bruin of >.tx-Tiinnlh('liiimani>inbFTO. nalunil 
tlw. iK>)lllk*r.) 



lalinii.-j fti»c wilii the <ilfai-iorv gniitfliii, t" wliicli ihc <iHin'iiiry itrrvif* |«iss fpom 
tlie imu-nn.- iiii'mbniiu- I'f tin- imsal ruvilv, :iiiil ihi-v lonii tin- ulfiirlnrif lnfit'ii, nr 
riiincnrrfihfiloii, the cavilW wliich tliey conlaiii iK'ciuiiing olilitemn-il l>ffore adul 
lite is attuined. 

Uii to the filVli i»i}iitli of clcv<']<>]>[ni>nt tlip surface of the lieniifplieres is' 
stniHmi. but at this time a (le|tivi^i< m ii[>|)cars at the i^idc nt' eaeb hemii^l^ere 
(Fig. 1*24) involving lliat (xn'tion uf the eorlex which lie>> uiimiHliatelv exteniuL' 

to the (iiqitiis striatum ; tni» ii^ the 
Sil/t-i"l> ilrfirrni-iuii. I^UiT the li|ie 
of the ile]>nwii(>n prow imvaixi eaeh 
olher, ihc upm-r one (iruwiiig iiion: 
Ri|ii(lly ami liiriiiiii)r ii dUlim-l I'oUl 
the iijiircuiiim, whieli oovers in lh< 
fliMU'ofrlic liejm-wion. This oiivered 
]Mirlioii iif thi' I'lirtex in the iiimila of 
<ie.*eri|>tive anatomy, the tiirf>ure be- 
tween the edge of the o[K'ri'tihini and 
the lower lip of the <leprei«i(>U being 
the Si/hlau /r'w»rr. 1» the eubse- 
tiiienl nxintht? of devclnpment addi- 
tional tiw^iiren appear, come of wliieli 
art- of Miflicient ilipih lo form eh-vu- 
lioiiK projerliiit; itilo (he ttivilie^ of 
ihe lalenil vi-iilrioli-.', liie liliijirHwim/iuK of tlie miildle horn and the mU-nr of the 
IKisterior horn being toriiii-(f In lliir> niiiiiDer. 

The lamina tenuinali^, a.- ban been ween, forms the front wall of the third 
ventriele, and aeeorilinglv eonneets the two ci-rebral hemispheres in fmnl. Irs 
lower part remain-* relalively thin, liui above it bi-eonief. mneh iliiekeiied from 
liefore backwiml, the ihiekening Imvriij: ii rriioigniar .-hape. In tin- ihic-kening a 
slit-like eaviiy apjH-ars. and (lirotigb thai |H>riion of the iliiekeniMji "hiih forms 
the riHif of the cavity nerve-tibres ]ioss aeniss from the cortex of each cerebml 
hemisphere to that of the other, forming the corpnn ciilliminn. while in the floor 
of the cavity longitiiilinal tibres dcveloi), forming the pilhir^ of the j'ornix. The 
wivity itself i< the so-called Jtjf!i rrntnvfr. its latenil walls being the nrptiim furi- 
ifum, null it i:" evident from its mode of developmenl that il cauiiot be ccjnfidcred 
hoiuiiIogonK with the other ventricle'^ of the bniin. 

One other m'I of sinictnRw rw|iiinL' notice lien-, though they niX' not iictnal 
Const it licHt)' of llie I'entral ncrvimn cyifteni. These arc the I'lim-uUl /Vrjimr*, 
which eoiU'iKl of (■i>lli<ciioni> of blood-v(Tss<ds deveIo]iei! in llie pin ovvr certain 
{uirtiiins cif i)ie brain whciv tb<' walls lire exeeeiliiigly thin — as, for inKtiinee, over 
the mof of the ihini anil liiurth ventricles and along llie fliHir of the latcml ven- 
tricl<i.>., 'I'lie vi^^ieU pii-h tlu'.-t- thin nicmbrnoi's in front of ihem into the interior 
of ihe br;iiii, ami thus nmie to lie appaivntly in thi' interior of the ventneles, 
thongli in ri'ality they are si-iiarated from them by the prolongation of the roof 
or floor wliLch they eairv in front of them. 

The Sympathetic System. — TIk- f.ym|>athetic ganglia have usually been regarded 
as formed bv a i>ro[iler;ition of cells from the anlagi'n of the dorsal nHil-gaiiglia, 
ami as being, theretore, of eetixlennal origin. More recent oliservaiiimi- tend lo 
assign them to the meseiichyine. their first tiiilicntiou being found in a con! of 
cells in the mesenchyme Just external to (he dor^il aorta. The liistory of the 
system necd-i further sttidy, however. i)efi>rc definite stutemenls am Ik- made 
couecniing it. 

The OlfatctOTT, OiiRt&toiT. and Tactile OrgraDs.— Of the organs of i>]Hvial xcnw 
the taetih- anil gustatory iit'i- not ii^ vi't thoroOiiblv nndeistocid embrvologieally. 
The i)H:ict<n'V oi^iit ap|H-;trs a.-^ two eiri'iiliir thi<'ki'nings of the ii'tuilerin, one on 
<3ich side of the fronto-na.sul prrH'erv-. juf-t in fiimt of the month, and the.-e. inking 
beneath the surfiiee, come to form the floor of a [air of deprettiions (Fig, it!)) 



i 

4 

e 

h 

I 




THE EYE. 



107 



wliiwc [ip!>.);ni<litiill,v»|i{>niiii'liiit^. fiimllv f'lw-, <-xt«-i>I bi-low. to fonn a pair of cavi- 
lii.'^, ihi* (>)K-iiiti^ into which iiri- th<- <ni/o'ior nanv, TIicm- tit ttr»T i-oniiiiDiiivjiU! 
willi iW month, bul iMvniiit- m-jumtu-cl fnan it l>y the uiiiui) of ihi* two mnxillary 
pnx*<*ft<, a .■x^iNiratiiiti fiirthor ixrtiwb'il hv the formniiou of tin* hard jmlate. 

The Eye, — Tin- (irit iiidiuiiion-i of the cyt- aro a nair of hi'lluw oiii^rowthfl 
froiu itio aiKt-rior v«fsiilc of the brain (Fig. ^'2'2}, aim ihpsc take ihf form of 
v<-ni(-li^ ill oonlaet with th** ectixlLTm oxtormilly and aiiidHJ (o the 'twi-iii-bniin 
hv Darrow optic litalkh. Tiiat |>ortioii uf ihi- wall of uu-h ve^iolr wliii-h \ii in 
mtitact with tllo cctixicru hec^rnvs iiiviifipRatvil. aitd thv voirli- tlltiii IxtHtmi-s 

. Cimvvrtiil into s duiihh--wullc(l nip, frxmi whom.- wulU ihv rftinti it funuod. The 
invairi nation prot-cwb moix- nipidly on tlM- uiidt^r wdi- of tlio vwfiolc, ami if €wn- 
tiiiiicil )iiii-kwan) Miini.' di«tiutcr on ihv opli«- ntalk, which Ihim hcii'iiK'^ ^iovhI mi 
iVt iindi-r '•iirdiii', th<- optic <'iip In-iii'^ iii))H!rt<-<rt jilon^ u narrow line on its tind(*r 

. fiurfao-, llii^ <>[K'iiin);lii-inj^ thi.-(7t"/YM(/(;/_/|M(tov (Fi^. 12>'jJ. When tlicri-liiia i.4e-.ita)i- 




Fh. 13&.— DlngrBUuof the fi>nn«tliiii nf tbiin|>llevi;|>aii(l rhnroHftl naiirr' 

rii:4>o<l nerve-fibres grow from it^ eelU toward the brain, ehmwinp the optie utiilk 
(as the jKitli of lea!4 ivwintdnee, and thus eciiivi-rtin;; tt inl>i the M>lld oiitii- iirrrr. 
Tliai portion of the aiirfaoe eitodcnn witii wliicli i!k' optic vehicle eainc in 

contact earlv b,>gin»i to thicken, and later lieeomi'-. invitjr- 

inaie<l. prec-ing upon the wall of the vesicle. Tliis eoio- 

derm gniihuilly n-parates frotii the siirfaiv and forms a 

splK-rical, hollow Kiriictiiri-. lyinj; in the nioiiih of the optic 

cnp: it is tlK^anlnpc of the /'■("<{ Fig. 12(J). I^ter. llieeelltt 

«f it* anlorior wail Maften dnwri to form the epithelium 

<ir the Icnw ( Kip. I:i7), while tli-i*c of the iwistcrior wall 

liiNvinie tniieh elonpitt-il, and an* converted into fibre 

runniitir in variou.- direct ion.-> iitKl eomplelely lilliri;; the 

original cavity. At first the Iciih i« in rhm.' eontaci 
,wilh the siiri'are ectoilenn ; lint Inter incsi-nehymal 

^taiie pushes in l>etween it ami the eeloderm, fonnin); 
layer which beeonies eonvi'rted into the mrm-rt | Kifr. 

127), the eclmlerni external to it forming the roiijnrir' 

tirn. At the same time a coneent ration of mesenehvme 

takes platv all nronnd the optic cup to fi.rm the xdrnitir 

RikI r1mr*nti isntfi' of the eyebnll. ami Iwtween the outer 

nirfiici- of the lens ami the <'oriu'!i Hiiid eolltvts, forming 

tlw n<i'*mu» huMiu: The rili'nniM /unit/ is formed bv the 

inignition i*f nii-^enchviii'- inln the interior of the optic 

cnp through (he i'hiin)icl fii>:<iire, and i» at fin't riehlv 

9ilpplte<l with hlood. the artery bringing it running 

along the gnxive on the under snrface of the optic 

etalli, and so entering the diondd fissure. In the later 




IVt IW - Si'ml^llnflfum «f 
Ihf •i*fv<n*!nn' *'[»lk v.?"t<'I<' nn4 
lh«H i*.'»i-U'iptn;z lf">" m, Xttyi^i 
wbl.'h hrf<nmi'* [Nltniciitnry roll 
iiiil [iL>\T^ C\ (lOAtvrl.iri^liaint'*^!, 
('» Imi .H^ciiiii.'rl \i\ vltriir.ti>; //. 
n-mrrHDI "f i^iJly "f (irlihrtrr 
.ipllc TCfll'-l'': /It. InyiT which 
tM'fMiii(.j^ ^TvatfT iMirt of rvlliiB, 

/.. Jc-TIJIh ii> u I'Up "(Wi ■111 vxl*^ 

H<ir: Wh V^ M. ru*'»i uli'mi 1 Jt', 
W, iMilniPi fn^rn ^hli"li mrw 
dL-nii £niU4 \u C'j Ikirm Irit anA 
hmU or vfiiva : *. t^Javv al 
uh1*'l> r]i4- liriirtilTy f.Tptlr tr*)r1i- 
hn* U'l'TirlthTiSh'il f'ur\ fl^ra liu'lf : 
•. i--.lnt of liivnirtrmtlfrti ■>( rrl^ 
Anna to tatiu leiu. (Wlolcr. 

llhCllll.) 




(W'^-lftiHiifiil ihc flioniiil fii^iirc rlos^s roiiiplptfly, and th« lips of th<r gixvove _ 
llif wlalk iiImi iTiwt ami clow, llic arlcn' thus Wcomiiijr enclosed by llic !<tulk, and ' 
fi>rniin)r itiv arlfriu ccnlralM rrtinw of tliv adutl. Later on, thv tniwvnchytiic id 



eOHHICTlVI-TISSUI tWVC 

or irHENOi 



■ccTua ■uriflion 



ccHTaaL amour 

«r RCTTO* 



orr.e H(iivf< 



«» orrie Bv» 



viTNkauB— ; 



■CCTVI 

irtrriv^cin' — 




ciiT*Taiun« 
criTHCUua 



IIIEHftfllim 
LOIMCn LID 




CftlAHV 



hUCIWIXT OF lAia 

>ia«ittT or mia 



OrOFTIC S«F 



Fis. W.— HorliiiiitBl wpUan of Iha dBvalopInR eye. (Alter RAIinior.) 

the intmor nf thf o|rtic t'ii[> ticoomos cohvpikhI into llit- jwciilinr ^'Intinoiit) 
tJK'^uc of which (lie vitninw in comjMisetl, and ita t>tnrKl-!iii{i])Iv I)i-oiinie^ cut off, 
the onlv tracp of the fxislenw" of the artm- in front of the rrtinn bci»]i the space 
originally occupiwi by the artery, pon-ifiting as a ranal traversinc the centre of 
the vitrooiiii, Hn<l known an the hi/titoid cannf. When the blood-supply of the 
vitreous is at it-i highest tlcvelopniont it extcmU a» far forwai-d ii-i the lens, which 
it surroumU with a vascular capsitle. which later normally diMipiHar* coniplflcly. 

Of the strunurcB accessory to the pye. the eyrlitii' <l«vclop as folds of i^kiu, 
which prow tupethcr over Ihe eye, and n-innin fuswl Itigclhcr until itlmrtly heforr- 
birth. The fnchrj/mrtl (/fandf arc furmcd m wJid ingrowtlix (Inter bc<-<imiug hol- 
low) from the coujunctiva. just »i th« ptHnI where the upiK-r-cyelid fnldn arii-e, 
while the liii'hrgmiil ifurl i,« dcvcl')pc<I as a lliickfning of the i^ctuderiii, which 
forms till' thwir of the priMive finuid at nn earlv stage between the fronio-nn^al 
and the niaxillnry |>rw.->w!*. This thickening later oecom pa hollowed nut, and 
the ii[»s of the jrroove mei-t over the cann! so formed, completely enclosing it, 
and, as the nasal cavity difiereniiateu, the lower end of the iluct coniea to commu- 
nicate with it. 

Tho AnditoiT Organ. — Th« mrtnbranouf Jobynnfh or inner car is the first por- 
tion of the auditory organ to develop, ajipcHrint; as a circular depression of the 
ectoderm over the first visceral cleft (Fig. 122l. This auditory pit dcciwns, 
■■inking down into the subjacent mcscnchyinc. it>* floor iit the same tmie thieken- 
ing, i«n<l it eventually iK-comc* eonstrictol oil' from the ectoderm as a completely 
c]<.wc<l •nc, M .•■mull pnK-eM fnini one cide of this rcpr<wnting the irniuJns of its 
coimection with the i«nrfiiec, and funning the ihtlim eiirtutf/ui/jfititicuK From the 
ventral wnll of ihe *tvr a 1ubnl»r outgrowth lorni!'. whi<-h in the nnlngc of the 
cxichU'it, ami in the luigte biiween this and the sic pn^per U to be foiuid ihi? 
audUortt gartgtioH, which hud pre^noui-Iy formed as s thickening of the Mtoderm 



THE AVtHTORY ORGAN. 



109 



WAtL or 
■ mn-anaiii 

HtOI»U« 
.VHICLV or 



Of uavHiHrH 



tfae auditon- pit, and Imd mijnvted into th« flubjaoeni nie^^rtichvnio. A t.-ui>* 
Btrictiou DOW b(^m« to form in tht iiiniT wall of the snc (Fig. I'JJt), dividiiiffit inio uii 
iipIKT and a lower jK>rtioii ; nnd from 
Ihf iipjM-r |M>rlioii Xwu Hut liullow diwv 
likr imtpnjwili^ dcvi-lop, om- "I" which 
liw in n horiwiiiltil pmnc, whili- Ihi* 
olhpr ij< iliroctt^ vritinilly, liiit {n Ixint 
40 that ih<- nnti>rtiir Imlf of It licv ul- 
lino:>t at ri^rhl aii^^lfs with t\w poi^terinr. 
Thea« are the anlii^n of the ttemieir- 
CT(/arrtrw«/«(Fig, !■'«)), which are finally 
formed from the edge.-* of llie di^es, the 
central portion ofihe horizontal disc and 
<rf each half of the vertiml one d!sa|>- 
pearing, so that three caimh) are formed, 
each o|K-mng ut both cxtromitiCB into 
the HpjR-r ]iorttoti of the auditory sac. 
At one t-nd of each ejinal a widening 
occtin^, and, from the nioile of devcl- 
upmctit jlWI outlined, it will be seen that the two vcrliinl niniils will hi' united 
tofri^tlier Ut onv cihI t<i form ii common canal before ow-iiiiig into tin- kjh- (Fig. 131), 
Thp coiiKtrietinii of the wjill of the siie di-i'pen» gniduiilly, itnlil fiiiiilly llie nminr 
pinion, or utru-ulait, comroii[iii.;i(i-.s wilii ihi- lower porlioji, or Htirritlitu, only by a 
nlendiT i-anal, whieh rtpn'seiits tb:i1 )H>rtion ut' the original sae with whiih the 
duelU-4 endolymphatieus eninniiiiiieiili-M. Wliilf tlie.-e pr ii-esses havr l)een g'ling 
on, a necond eon.-<trtetion ban formed belwfcn itie eiK-hlearanlage and the saeeidns, 
whereby the oonneetion of these two jwrts is also redu(;ed to a sleiwler t^nal, the 
eanalu rewniens, lu eorrespondenee with this division of the origliml nic a 
di%'L<ikiii of the auditory ganglion ul^^o nccur», one portion uf it, the ve^ibufar 




Pir., 128. -Wi'i'ilun Ihroimli tin- miimury Te>lcl« ot 
« i1lii.'V|i vmbryii. UliTLMiKs oftrr IWH'Llchcr.) 




intn-BBirx 






■CIBIUUB ciniii 
.rxfrntow gctwrtN 

UTHICULAB *10 
■ aCCULUa FOHTIOHI 
OF UkOOIIHTt* 



no. !».— swiloo throuuli the ou.llurjr tqticia of »heep ttabiyo, ■omcwluit oWct (ban ihu lu Fia, im 

ganglion, being in rclutinn to the sennory epiiheliimi of the iiimnhii', lineciiliis, 
and semioireular cnnnN, while the other in drawn out into an elongated hand, Uk 
mirtU or ctvhimr tinngUfM, which follows the coils into whieh the iixhh^ liewmios 
(Iirowii, and htaml.* in relation to iht- organ of Chiii, which develo|(ft from (he 
cochlear epithelium. 

Id the mean time, a condensation uf thti mesenchyme surrounding each audi- 




no 



EilURYOLOQY. 



tory sac has been takine place, and the purtiona of the lissHe immediately 
contact witli the wall» ut tne aae become eonverletl inlo fihriHK* e(.iineeiive tissue, 

and so strengthen ihc walls of the mem- 



CHOOfrH 
•H*TICU>. 



BEMtCIR CJkN*L 






uTmcvLue 




*o«T. vtaTicii. 

■(■ICIN. <HltX. 



¥ia, (»►— M<«l«l c,l inii^rtiil rur 'if hun»n ptn- 
bryo uf about nvi- xt'vki. (C t. Uluci. klWr W. 
Ub, Jr.) 



bninous ear, while the oiiH-nnust portions 
V'tHimt'convertol inloMirtilii^.nml later 
into iKiiie, lormin;; the jHTiotif eapFiile, 
in wln>»-e wuJN, ln>wev<T, itiriT nii-mbra- 
(imiK arciif- arc \vi\, imo nC llirj-c V-ing 
« Ih-h- ti t*!!!)!!!, llif iliii'tini ]ii-rilipiij>hiiti- 
CUK, U'UiU tViiin llic )K'rilviiiiiluilie »|ici(-o _ 
to llie Hnrliiec- of itie bone. Ketwcen thefl 
hiMiT whII of lln- (-a)Hiilc {which is i-otn- 
pi.sed of tlenrMJ hone, and fornix wlmt is 
termed the <mw(V)ii« lahximilli) and the 
oonneclive ti^itiie a layer of the niewn- 
ehyme is left in the form of a loow 
eonneetive tisi-ne, which siibR.'(iuentIy - 
degenerates, leaving n space, which lie- B 
(romes tilled with finid. iinniiid the niem- 
briiniins ear. This ip the {Hiihjtiifflnilic 
H-|»iinited into twn ]mrts hv ihc nicnibninixisi 



fjiari; which, in the itM-hlea, 

WH'hlcii. being iittaeiied on cither .side tii itf w:dl, "ii fliiil ii K-ciiori uf any «oil 
of ihc ei.H'hIca will ishow the nu-inbmnoni> tixlileu, Icnown in nnaloniy a?< \\w ifa/a 
mfiliii, with 11 |H'riIynipliati<- ^pmrc above ii, (he Kriilit rentihull, iiml anoiher helow 
it, the iH'iilii lyMjHitii, tlu-M' two spaces eontniiniicaiing, however, at the a|K*x of 
the eochlfii. 

The niiildle ear in the remain.^ of the, first vi.-wvral ileft, the groove on the 
wail of the pharynx which represents the cleft becoming converted into a canal 









Fid. ISl.— Model of liiti'i'iiii 




rO%t. VtKTIC'L 

(■nieifl. c*«>*L. 



[ MunianvDibnru orsbout two monllw, |(*, >>. W iiiit. All«i W. Hl>. Jr.) 



by the fusion of itf lipw, the tin|)er end of thi" cjinnl being enlarged to (orni a 
cavity, the i)/mprin!r ftirr/ji, while the rest of it form" (he EtiMin-liU'ii eiiimf, which 
opens liehiw into the phnrynx. Th<- lyni|iaiiie i-jivily is. Imwcver, up tn birth 
exre<.-diiiglv niirrow, pnietic:dlv merely a slil, its w:ilU, iH-neath the iniiciins meni- 
lininc lining it, being liirgi-Iv conijMweil itf a loo.-«- geliitiiioiis li-jsne, in wlii<'h lie 
inibediled lline Mnall Imnes. llic iiuiIIi-uh, mIiiju'i', and iiiruK. The np|Mr end uf 
Meekd's lartilage, which develop,-;, a." has Ihch swn, in the lir>l hninehiiil uivh, 
sciwnite-s from the hiwer |K)riion, and forma twn ••matl bones, which an- iinbed(h'<I 
in the fixml wall of the tvm]umum, and are the mallets and inen.- ; while the 
fttapes seems to he produced by the fusion of two distinct ]Mirts, It.^ flat ]iortion, 



THE AVDITORY ORGAN. 



Ill 






inM» in oiir of tltc llin-o iincK^'^fted tiimts of the oosnoiiii mptiiilc ofllto inior- 
iral »-iir, iIh' fttninwH wilf, .•vt-eni;« i<» Ix? roillv llii> jxtrtion of (h<- wall of the cajH 
kiilf which siiould fill ihin torumen, (he ino!«iichymtr iiuiiiMlialcly nnidml il having 
rr-m-nitii'ii Ru-nil>nin4>u>, while iw art-li is the oBsifiwI iiputT end of ihc oariilage 
<>f ihi* ]^i'<iikI hninchial ardi. Tlit'^c Imuk's are iil tir>-t iiiificiltlml in ihe ^^vLiliuoits 
tif-^w of ihf wall of (lit- (yni|Kinic mvily. After hinh, nir i^ biUvn iiKo this citvity 
'"^nm^h (In- Kuf>iachian tube, anil tlic I'avity ciiiHrp'!', prfsj'iiin iiciilc tin- Rvlaii- 
ii-* ti.^Mtie anil ^nrruuiHling bonrt-, whi<-h thii" form n chain ■.'Xtt-mlirig fix>iii the 
tyaiiKinic nieiiihran« to the funinu'n •■vale, awl H|t]uin-nily iKff.iiii^ throngh the 
iui<tilt(> of thi^ tvmnanio cavity, tJiuiigh in ixaJity tln-y un: fiicIoM-i) by the cniK-onif 
meiiibrant- whieii Init-!' the cavity. 

Two of th? (hrco uno^^iHi-'il ^jiares in the wall of the osseoU)^ capf^iilc of tlic 
inner ear have Ik>pii acL-HKiiiteJ for in the ilncdin |«erilym|»lia(i<iis and (he foRinivn 
ovale : the (hird nnenin^; i^ the foranu-n r<tlundatu, which is closed by a nietnbraDC 
on which ih? scala tym|>ani abiitx. The outer wall of the tyni|Kinic <sivity is 
fortnet) by the tgmpanir mrmhntn'', and in nl fiivt thick with ihc jtelatinoiis i\f»\w 
which eiiclfwes (he auditory o-^iclei. it Iteintr only af(er bir(h tliut it \^ rcdncod to 
the thin mcnibnine found in the adult. It \s formed partly by the (lartition 
between the exti-rnal and inleniiil yroove-i of the fir^t bninchiul cleft, and [wrtly 
ij the upper en<i» of the tir-t and second l>r:ineliial arche-i. 

Juist oA the inner groove of the Hrst bnineliiid cleft form* the Kn«luchiaii liib« 
I tympttnnin, !*o the npper end of the onter fir<M.ve of the sitnic elt-ll forms the 
e»r. the jHHU'i devi-loiiiii^ from eleviitionH iipjH'itring on thft Ri^t and i«ecoud 
I urclu-^ ii^ lh« vii>inity of ibc )>erMi.'<ti'nt [mrt of (he grcmve. 



THE BONES 



Bv GEORGE WOOI^EY. 



rpH V. adult human skeleton oonEistfl of a ntiml>or ' of hoiitit, wliti n f>nnft1l nmount 
X *it' ctirtilatff in some partu, whtre (hi'V arc juimd or artu-iilm«^ wiili one 
auoib«r. The bont>, a^ ihcy are generally i^tutlied after maceration and drj-ing, 
are 4;onipu^-0 uf minenil or nirthy s»lii>, prim'ijmlly phosphate and carhooate of 
lime.* The soft organic parts, of whivh a i)repan?d hone is deprived, consist |>artly 
of thelihpouBandvusciilarwj'iwrf<-um,whiHiouvfr» thccur- 
face and is continuous with tin- cHuiiKi'iiiig hpimvut^, und 
thf^ \mti\d(aar nmm)w, wtiioh fills tin- inliTimlcuvilit?, and 
partly of thi- (oiin''- Ih'X'hIc. iiniiM:il iniiifer, wliirh retains 
the *ina|>c of (he 1>oik- uhi-ii ihc viirihv niattvr in n'liiovi'd. 

The main,/'mi<,'/'<»w of Imnt-.s aiv tojiflonl a nulid franK-- 
vrork, to KiipiKirt softer ]iiirt.-<, to protect ilelicute organs, 
and to mTKf for tin- atlai-h^ient and ti^verafcv of imiticles 
whii^h pnMluoc ihv fUftercnt niov<;nient&. To serve these 
fliflV*rfiii piir|H»i-s lionf.-* miiM differ in their oatu-ani foi-m, 
•cconiiii); In uhieh wo disiingnisli — (1) Jjonti boiit*, caa- 
)'islingofa.'«haflordiaphvsisan<! twoexitanded exireniities 
i>r epiphyses, a.'« in liio linih^. They allonl supjiuri and 
levcrruge for moti<»n, and are iiAimlly somewhat cnrv«-d in 
«n« or two direolionn, (lni» set-uring greater clantieily and 
strength ; ('1) Flat fitinoi, a.^ in the jM'lvi.j, hnipida, and the 
nxif of the nkull, affonling protwiion and snp{x>rt to the 
vonlained ]Kirtf>, and alno mit^ienlar attachment ; {'-i) Skoii 
lione»,as iu the wrist and ankle, where strength cooihJned 
with free motion is required ; (4) Irregular or mixed boaat, 
like the vcrtebrw and many of the boues of the skull. 

Int«nul ATTMigement. — Un lougitiidinal section of a 
long Iwme (Fig. \'.i'l] nutiit lliiit tlicrc i» un otifcr lavcr of 
tiam, f-ompaet /mbtfajict, varying; in thicknos and cneloniiig 
a eentral or tnfdnllary cor%, in tlic i^halt of llie hone, und 
jKiroiis. fipongy or eanrrl/ou* Ixmy tissue at llie cxtrtmi- 
ti^-s. In th« ruiwnt state the raedtilinry tavily i>< tilled with 
yellow or/nfly murrow, and tin- e»vitiei< of the cnmtc-ltoiis 
tissue with ml mumnr. Sliort, flat, and irregular hones 
have nil onh-r layer of <-(mi|>;tet .iiil>slanee, enclosing can- 
cellous ti.-vue ivtiitaiiiin^ red maniiw. The cancellous 
tissue at the eRd.-<of liiiig liones and in other hones henring 
pre^nrc is so arranged that it^hony laniellieare prineipidly 
directed in tlie linetj of pressure or of mii«cul«r tenKiuii. 
The porosity or hoUo\rnes« of bones serves to comhiiw 
requi-iite >iice and Mrength with lif^htni:^o<. 

DcTelopamt of Bone*. — Iu the tiirty embryo the bones are preformed either 

' RxdrndTwofiliocMdclMnf l)i« nuis the ircib. and llw Worniinii liontH. (lii-n* iin- ^)0 bourn, of 
wtikli 64 un in tli* omxt cutrrmity, Si in tliv louvr, and 74 Jn iho inink. dialiibulcd u foUotm ; Uic 
twrtKbral coiuinn 3^ llic skull 'i'l, tlir rilm iintl Kti-miKii 'J-'>. utii) iliv Iivi>id l»iiu !• 

* Kwpoelii^y At per ccnit. anil 1 1 per ctml. of liic fulidi of frali ^c. 

» 113 



Flo. 132.— The loaeltudl- 
na) tertian at a lonjt bone. 



lU 



THE BONES. 



in nifniliraiie or, in tlie majority of r-asi^s, in cartilage coverwl bv me[nbrnni>, w> 
tliiil nil HIT |K>!«iy*«e<J oi' mombnini-s, am) uv-iifnation l«^neat!i membrane L-« louiid 
ill all, Mini cxc'liijiively in suine.' One iir more orifjiual or /irimfifi/ ri'iitrfu ajijienr 
for i-arli h<ini-, fitmi which unfiJlication proceetlfi, forming the dkijthi/sM (" l>etwe<^n- 
growth") or bixiy. After a varyiuj; time one ur !M.~venil leeondarif or tertiary 
cciUir/i may appear, which form the cpiphi/nes |" n|M»n-Krowth "), nnih-d to the <Iia- 
phyais for some time by cartilage. Some of thow fumi tlie extrentities of h>ng 
boaei^ other>i projecting proceiwe* like the uvrumion of tho H'Jipiila or the tro-, 
chanters of the femur,^ 

Bone formed in ojirtilage Is not n<lu|it('d to he iHTinaiient, tor the airtihigo 
M non-va«enhir, ami, further, it is not iriie Ikun', bin :i inert- i-iilei(ien(ioii. It is 
tiicrefore rtisorljcii and rei)lnc'cd hy vasenlar honi- fi-om an osHilic a-ntrp beiitiitK 
the niemhmne. 

In the long banes t\w lip*t. or primary eentre in th<! shaft ajmcjirs before birth.* 
Ijalcr, nni? or more rn'cwwlary «'nlre.-> apiR'ar at either end, all bill thn** after 
birth. The iMme-oentra-i in ihc .■«liaft and extremities of l.mg l>onex are separatrti 
fn>m one another by a layer of eariila^e (e/jtyjAi/srf// •■miitat/v), wliieh continues to 
grow at the same time that the bone-centres on either side grow into it. By 
this mean* the bone is enabled to increase in leii};tli, until first one and then the 
other eartiluRe censes to grow, and the shaft and t-stn-mitics nnite by ussilicalion 
of the intervening layer of wirdhige. Sneb bones grow in diameter by the 
dG|Kidit of hone beneath the [leriostettm. Bones in which ossilii-alion is begun 
and compIeti>d tii nienibrane, ns in the \-iiiilt of the i«ktill, are enabled to increase 
in size by the growth uf tlic membrane in the Mitiires se|)arating them, nniil ihey 
have attaineil ihcir full ■•i/.e, when thi.t growth stops. 

Until tho epiphv.^ml earlihigi' has ossified separation without iMmy fraeture 
may occur here. The date of this ossifieation is therefore of imjwrtanee in some 
oaW9. The bony union of sliafY and extremities takes place according to the fol- 
lowing rule.s: 

1. The extremity whose osiifie oentre is the firm to ap^war i* the last to nnite 
with the shall. Exception : the lovrcr end of the Hbula, but the npper «nd i« 
veatigial. 

2. The extremity toward which runs the nutrient artery is the first to 
unite. 

3. The nutrient arteries run toward the elbow and away from the kn 
L e., down hill — if elbow and knet^ Ijoth be Hexed. 

4. Union of the epipliyseii and diaphvses of long bones occurs from the six- , 
teenth to the twenty-seeoml year (iNxi.-ionally twenty-fifth year, tibia), and 
eariier in tho np|)er than in the lnwer extrt'mity, 

5. When two or more oentn^ nf cMnification occur in an epiphysi*, iht-f^c unite 
tfl^tbur before the eiiiphysi!* uniti---* with the diaphy>is ur filiaft. 

Many bones of the skull art; ruinf/iutitv, or iiiinle op of iwy ur more clenient«, 
(•cptimti- in their embryonic development, in young bones, and in the ^kiilb of 
other veriebrjtes. 

The study of these details and the eom|«irisoii nf (be hnrriaii anatomy with 
thut of other vertebrates, on the IklsIs of their development, ennslitute the study 
of morphology, in which the most reeent and interesting ailvanees in anatomy 
have been mode. 

DeacriptioDS of Bones. — The r^tudent of osteolog;i- should alu'ays have the actual 
b<mes in his hand as he follows their deseriptions, remenibering that the latter 
represent the average of bones, and tlmt it is very rare to meet with a bone in 
which every detail corresponds to the description. 

' (>>tir>(.']ilirni oniiiiii(Mic!nK >ii iTieinbniTie iimy inriiFv ajiil ruplorc <'iirtiliici\ a* iu thr dnridtL 

' I*f«miiienl pmjecliooji not liuvclopwi from iiiilc^inidnnl riiilpw nn- i*"lli-ii ajK/phym. 

' M«iiy ptimnrr coiilrr* of nodfiriiUiin niipcnr nflir Wrtli, or in (lii; i'iir|"il Ihiihw, 

* Tlie aijjuiuliiK tiiiLi of (ii« feinuT and tiuiu, uuil HiitLutioiw tlic hcnd o( the liumurua. 



I 
I 



THE ilJ*IXIi. 



115 




■iiiri]iot> of vrtimg bonps is oomparativelv Mttiontli. Tho roiipti lines niwl 
ridgT:^ an a<lult Iwini^w an- due to ossificaiion at the allaclinn-nt-> of iiui-cU-*. Any 
marked bony pruniiuencc may bo called a proctm t.r apotikyais (" out-gmvrih ") ; 
if blunt, a tuhtro^it^ when large, a tuh<-reie whea small ; if shar|i, ii »}»iir. or 
gpmowt proc*va : if Xoa^, a Une or rklffe ; wli^n Barrow, a «r^ ; if bniad, a <*<'>((']//€ 
("knuctite") when iirticitliir, or ii head whcQ »iip[)orled or a conntriclcd |>tirt 
or nrct, A dejircssion or hollow f|«icf in or upon a bone or Ijetneen pcvt-ral 
bou('« ii sonictimc-Ji willtil u /'«wt T'liStoh"). A r/frnuid ("cavity-tike") /owa 
if a T^liullow urticiiliir dt-pn^on. ii fofymV/ {"cup-Iikf ")_/owio is a deeper one. 
•S'/ntM and anthtm are U-nnti npplitil to cnvitii.-!< within eertain bonvt-. A^'mmi-c is 
a namiw xlit ; n fonwtrn, a Iioh- or yrifiw ; a cmal or mraitu, u long, tiibo-likc 
paiMigp-way. Other ternw tiwd n-tjiitre ii" oxplurmtioii. 

tn dt^scribing (hi.- diir(Ti.*nl usiH-el-* of a bont; or otlwr aiiatntniml imrt tlio 

boilv bt iiiip|M>s<>i) to bi; in (ho vnvt jmnition. A i^nrfntN*, cxtrcinilv, or omiilt |iart 

dins-lwl (owunl llwr heiul i» mlli-d sitjirrieir ; lowani tin- fci-l, infrrhr ; lowiiiil iho 

front, eeiitrtil or anU^rior ; toward the back, lU/nutt or jHmtmOr. Tliat aspect 

I dirwrled townnl ilie niiNliait, vortical, anIero-]>o>iT«rior plane of the b<Mly U tnlled 

^^n/M-nd/ or uu-Mut; thai a\ray I'mm the mme ntanf, external or Intei-a!. 

^^ Certain itrea-H on bone-, are devoted to the attaohmonl of mnMeles. I'siially 

^fach extremity of a nuiMole is fastened to a bone, the proximal end being ealled 

it^ origin, the distal end its insertion. The muscle is saiif, theivfore, to Jirise 

fr*»m the one point, and to 1m? inserted into llie other ; and the bones, respectively, 

are said lo give origin to and insertion to the muscl*. 



THE SPINE. 



The mine, or Vfrtebrat column, is composed of 26 superimposed bones called 
wrfafrnF ("capable of tnrning"). The name «/>tW is derived from tlic series of 
spines or spinous processes which arc the most obvious portions of the column of 
bones in the undissectcd t)ody. Of tlicsc, the npjvcr 24 an- fnif <)r movahlf vcrtebrte, 
snd an- divi<lcd from above downwani into 7 Cfirici/, 12 (Awf/ctV, and 5 lumbar. 
Of tbc two lower (i>mpi>«tc bone* comprixing the /«/*(- mirhm; ihc np|>cr one, or 
mrniin, \f. fonncii by xW- fiixion of 5 vcrlcbnc, uiid the Iowit one, or t-mi-;/j; of 4 
ankyl'we^l, vestigial, ti-rmiiial vertehne, all Hi-jMinilc in early life. 

A Epical vertebra consinl.-' of a 'w/^ or <>'rifn(r;i in front, with II /<'-(/r-ri/»fT/i behind, 

which comph-ti's' (h<! rrriebral or *i>liint foramni, lh<- scries of which forms the r<!r- 

ritl rtiiuu in which the sptnal eon! and its nienibnines are-liKlged and protected. 

The disc-like fcody snp)>orts and hears the weight of the heaii and trunk. Its 

pi'Hor and inferior .-iirlai^es are Hattened or slightly concave, and i-ongh for the 

nnecling intervertebral discs. The ciri'^innferenee is concave vertically, convex 

horizontally : but liehind it is concave in Iwth directions, where it boniKls tiie 

rertebral titramen ventrally and pn'sents lai^e foramina for veins. 

The neuraf arch is formwl of two symmetrical halves, and consist* of two 
licles and two lamime, supporting seven processes — four artieidur, two tnit)«- 
rM>, and one spinous. 
The pedifte* ("little feet"), or ventral part,* of the iirc-b, wnniT't of two iiar- 
niw, thick piers of hone, projecting horinontally back fn>ni the npjn-r iiart of the 
diir-uil and extvrnal aspect of the IkkIv, .\bovc and below the i>etlicles are the 
trrt^/ral »otehf», which, with the notches nf adjacent verlel>ra.', form the inlef 
nHfbrtiJ Jommitui for the (KiS'Mig<- of ihi- ?>pinu! nerve:* and vessels. 

Ttic Inmirtrr, brond and flat, i'Oin]>Iett- the arch by fusing together in the median 
ine behind. Their ii|ii>ir VioiilerH and lower anterior parts are rough for the 
attachment of ilie ligaiuenla sitbHava. 

The tftinoiia piytt^M projects b.ickward in the median line from the juDCtion 
uf the laminie, and servM for the attachment of nitisclcs and ligumcats. 



116 



THE BONES. 



The frnnst'crse procrtsa project oiitwnnl from the jUDCtion of the podk'k-s a' 
lanuDfe on cticli siuc. 

Tiif urtirtihir firorcMcs prvavut aa up]>(tr ami « Inwer jkair, escti'nclinfr upward 
iind ilownwiinl from the omUs of (hi- tniii.-.ver!*e pnx-i-ASi-ft, for articulntion with 
tlie pairs above ami hrlow. Tlw iirllcular ."urfiices of the upper and h>wcr puirs 
look ID opposite <lin>t!lIoii!>. 

Cw^al procetitji, wUcn prewnt, ttpriii^ from the sides of the body nt or 
thejimction of the latter with the |>e<licles. 



THE CERVIOAL aROTIP. 






eOBTa^TK4NI 




•■HOC IBB. 



Fiu. m— Ccnleiil vcrMbn, viewed (Mm ftbovo. 
tIMUtj 



The ttjii'iMil cerviea! eertebne (from the third to Uie sixth, inehlwivc) (Fig, ]33) 
are espeeially chHracterizod by the foraniiuu in llie transverse proeesscs. The 

cen/rum, or hotly, is small, oval, and 
trausverseiy elongated. Ite Mpper snr- 
fiiw i-i coiicnvo tniiisvurst'ly, due to the 
elevation nf its Intend niar^nii into 
lip;< wliieh iirtieulate with the rounded 
lateral itiiirgins of the lower stirfnec of 
the verti^bra iibovi-. The lower ventral 
margin nrojinrts downward, .ho &* to 
overlap tlie rounded ventral niart;tn of 
the upper surfaee of the verieblii tieliiw. 
The aeptli of the body is equal in IVont 
and behind. The pfdiclen are directed 
obliuiiely oiitwnni and luiekward from.' 
about midway Iwtwccn the upper and lower iHiriiiTTi of the Ijody. The Inminm 
are Inii^;, iiarruw, and nion- or less tlattenrd t"it)ui above downward. The fpinnv* 
prtictDi^ is ishorl, bifid at the extremily, and nwirly horixonlal. Tlw Intxsvrr^ 
priuxjfum, dirceted outwanl and forward, arc st'i'ii (o be rather t^Iiurl, and their 
bifid extrcinilii'.« pre.-eni venlnil ainl ilorsjkl tubercle!'. The huM- of f!u<'h tnini?;- 
vewe pro^'^-^^ !.- {HTtbrated by llie riuitit-lnxiurrrritti Juri'iiini, whleli traiiMiiils tlie 
vertebral artery and vein in the upper stx vertebne, iind which dividi^ the base 
into iwo roots. The doi-sal root .-pringn from the junetion of the [ledielen and 
laminie, like the [horaeic transverse processes; the ventral nwt springs from the 
side of the IwKly, corresponding in ixisition to the vertt-bral end of a rib. It is 
a vestigial rib (t-oirf't), and is called the conlal //rwt'^w. The sujM'rior titiimlar 
pt'ocfivea took upwan.1 and somewhat backward, the inferior downward and some- 
what forward. The /orainen is triaugtdar, and larger than in the other i-egiona, 

PecnliftT OerricKl Vertebra. — 
These are the firj^t. second, and 
neventh. The jK-euliarities of the 
first and m-coikI are ^ueli as to 
allow llie freest nioveineut of the 
head on the spinal eiiluiun whieh 
is win.iUieiit with the .safety of 
the spin id cord. 

'liie atlas or flrst cerrlcal 
vertebra (Fig. ]:tl) laeks a body 
and spinous prwe-s^., and fi^rnis 
a ring consisting of two ttn-hai, 
ventrsil and dorsal, connertinf{ 
two tnleral mrwiw*. The Awty ha?i l>ocomc separated from the atlas and ankylosed 
to tlie axis a.s the iHlontntd priMre*s, The rcntrol arefi, one-fifth of the ring, pre- 
sents in the median line in friinl a ^inall tnberele for muwuhir and ligiinientous 
attoehment, and behind a oireular fiuret for articulation with the odontoid process. 
The dormi areh, two-tiflh.s of the ring, haj* « niedian tubercle behind, the nidi- 



I 



I 



c«* TO- Taa na- 
if ma E teitAHiH 



minavcatE, 

pnocc** 




Fie. lU.— Til* «tlM. vlvwHil (hint kIkiveu iTwIuli 



L4 



THE CEBVICAL VEHTEBB^. 



117 



tncnt of a ^[Mnnti-i pniw**, which, if present, woiilil intcrffn- witli tho rotation 
lH>tWcei> the alia* iiml iixi". Oil it;* fi[>[HT titiriiicc, iil the junction with the liKcm] 
mass, is a deeji jrnxiv)', Mimctiincit u foninion. fi>r the puiwigc of tlu- vertcbnil iirtorv 
and the first apinnl m-wc. Thi^ gniovu or nourh uu ili^iindvrF'nrfacu, tor the scc-und 
spinal nerve, i!« al^o behind the nrliculttr ])nto<i!#, whilo tliv lower splim! n^^^'v» 
I>ass oot in frcHit of the artietilar processes. The Intrr'tt inoAtfM prtwnt altove iwo 
oval, elunKnied, articular Rurtaees looking upward nixl inwnni. anil liivcTrinp 
ly.'hin<I. These artieiilate with the condyles of the oi-eipitiil hom- and jwrmil ifin 
niMldin)* movements of the head. Transverse grooves may dividi- t!n-»c oiiHutH^ 
in two or give them a kidnev-shaped outline. The inferior articular jircx-i-.w*-*, 
or tin* fai-ets on the under liuriace of the lateral masseh, are neariv flat anci ciruuhir, 
looking downward and slightly inward. Their atticiilation witli the a.\is iicrmilii 
the rotatory movemeute of (he heful. On the inner surfitee of each lateral mass, 
bttwet-n the two urtieuUr priKjewiei?. i< a liihercic for the transverse iiginnent, 
which diviiIcK the interior of the ring itito a (iiuallcr ventral ^egtnent for the 
odontoid procf^vi and a larger dorsal K-gincnI, the spinal lornnien, for the spinal 
cunl. Th« trani'verse pro('(^««0« are long, mtv'c for tin- leverage of the rotator 
iiitu«d«s of ihe liMid, uitd aro l<.> l>e felt IxOnw (lie tntu'toid proceiw of the temporal 
boov. Tlie fonwn«« in them is lai^-, their <<fiHtHl pnjee-vie* arc slender, and their 
extn-milii'-i l>nxi<l aii<l not bifid. 

Till- axis or socood vertebra (rcrftftm dentaia, " tootlml vcrtebni ") (Figti. 135, 
130) haa a lai-ge, strong l)ody, surmounted by the odanloUl (" luoth-like ") pncag. 



ft*Tieuu>ii <un»ec 

(OH VtHTIUL 

«aen or aru*- 




O0OHtOI» »M0C1*S 



•ll«0(*l. 



IHflHION INTIOIJ. 

Pni. ifit.— Tbaazb, Ihint \'n:w. (Tcaiut.) 




roil VEItTKAL 

■nCH or «T1A«. 



Pia. lita.— The kx!>. lu riElx lidc. 



ITotUt.) 



on which ILK n pivot the atlas rolat«>!t, currying with it the head. This process has 
in front a smooth .lurface for articulation witli the atlas, and behind, at a slightly 
lower level, a sn»or)th gnM)ve, which forms a constriction, the neck, and receives 
tin- tran-sverse ligament. The lower surface of the body is like that of the typical 
cervical vertebra, except that the overlapping lip is more pnimineiit. In friml 
the ImmIv pn-sents a verticitl median ntlgc and two latenil di-pri'.viion^. Th« 
pe<iicles are stout, and ]«irily on them, purtlv on the IkhJv, re.«t the oval Mi}nTior 
articular surfaces, close to the bjist- of thi? odontoid pn«'e.s«, and directed upward 
and slightly outward. The weight of the head is inuisniitted to these surfaces 
tliruugh tlie latenil mii'^Tie.'< of the iitliis, aixl from them it passes largely to the 
body and less lo tlie inferior articular pnici',-ses of the axis through a strong arch, 
the piers of which are tin- biily and the infiTior articular processes. From this 
point down the weight is bonie maitly liy tlii' bodies. The inferior articuhirproo 
wscs niwmble those of the vi-rtebra' beh>w in form, position, and direction. The 
fpinous pnie«!ts is strong, deeply hilid, and grooved below. It gives uttaehmeiit t« 
muiwlM which rotate the hejid. The transverse processes ar* short. The costal 
proensaes are thick at their bases, and the anterior tuberclce are very rudimen- 
tary. The foramina for tlie vertebral arteries are directed obliquely npwani and 
DQtwarfl lowanl those in the alia*. 

The seventh cervloa] vertebra is called the veHfbra prominm*. fnun tlie length 
of its spinous process, which is a landmark readily felt hcneiith thcKkin. This is 
0(A bifid, and it gives attachment to the ligameutum nnciue. The costal processes 
anil their anterior Inherclcs are small, but sometimes are larger and segmented off 
as cervical ribs. The costo-transvcrw foramen ii< !«mall. The transverse proc- 
tue» are largv. 



dC_ 



118 



TUE BONES. 



The s]itnoug process of the sixth cfrvietx} veiiebm is occa^ionully so lonp t» 16 
be mistaken for that of the wevetith, and tlie anterior tiiljcrele iif its Ininsvcrw 
])roce!-» is caHcd tlie txtrofid tiiberi^r, lut ngaiti)>t it tlie ejtrotid artvry may bej 
co[uprcsfH.-<]. 

THE THOEACIO GROUP. 

The fkoracie vertebrcr (Fig«. 13"-13f>) are typically olinnicterizeil by the pr 
ence of artieular facets on the bodies and tniiisvprtif |)ro(i'i«<es. f"r Hrttcnlntionj 
with the ribs which they supimrt. TliC dise-like botli/, or ctfilruui, is uval o^l 
lirart-fihaped, only slightly wider transversely than from beforv baokwnrd, and] 
dct-pcr bfiliind than in front. A\'hi;iv the body joins the arch two denii-faocts araj 



eiHirjiciT ram 

HIHO Of KIB. 




auriHion ikRTieu- 

LJkR PflOCCS*' 



ricIT roit TUBt«< 
CLc OF mm. 



Fk>. W.—X Iboncli) vpitt'bra. iippsr mrllu*, (T«aliit.) 

found on cilhpr side, one at the upper and one at the lower border. Each f* 
with the conlignoiis one on the adjacent vertebra compli-tes a eavity for the head 
of II rib. The lower verlehral niitvlii-it arr deeper tliiin thi- n]i|K.'r. IC'ieh pair of M 
broad, fiat hniina is iinbrioated, or slojieil, over the pair below, like the tiles of " 
a iiwf. The gpinous prtufM in long and Ihree-sided, and prujects strongly down- 
ward, I'sjiecially in the middle of tlie series. The frannprritf jiroii-ii^s project out- 



TECHAL H0TCN, 
DEMiriCtl rOR 

HCAB «r ma 



■ OPtmOll (BTICU- 
LAH PROCCS4- 




f*ctT ron 

rgacRCLt or Mi^ 




Pta. IMr-Thnnidf vpttvbni. a^rii tntta Uio Irfl *I>1«. 
(Tmml) 



rto, m~Tli(>nK'lo itm*t>n, vl«tt«d ftMn 
brhiniL (TtBtnL) 



ward and slifrhtly baekwanl. The oval facets on the frtmt of their tijw arc for 
artionlation with the tiit>crcles of the ribs. Tlie rib In fitu fomis with ihio pnM-«<« 
a costo- trans verse fonimen. Of tJic twojwiirs of arlirular prwfstics, the articular 
surfaces of the npper jmir look buekward anil slightly outward and upwaix), thonc 
of the lower |iair forwiinl and slightly inwani and downward. The foramen \i 
round, and not so lai^ as in the eervi<»l or Itinibar region. 




THE LVMBAR VERTEBRA. 



119 



PmvIUt Thoracic Vertobrn. — ThcBe are the first, ninth, tenth, eleventh, and 
twrlfth. 

The flirt is a tranftitional vertebra, resenihling the lower cervieal vert^-bne, 
citpeviully iMi its iipi^er surface. The t)ody is elongated transversely, and lipped 
lalemllr abtjve. Tliere are entire facet;* above for the first pair of nbe, and demi- 
fawtit t«'l(iw for the tie<'OHd jwir. The BUjM^rinr articwiar processes have lai^-Iy an 
njiwonl liircction. The H])iitoti!i process is kmg, iicarlv horizontal, and even mors 
pnimincnt thiin that of the verfebni pnmiinens. 

Thi- ninth has ilcmi-facct»; above, but frequently none below. If the lower 
ones art- pn-M-nl, it is a tyiiic^il vt-rtebra. 

The tenth artieulates with but mio |Kiir of ribs. It haK no demi-faeets below, 
and the upjNT fiwets arc iisiiiilly coiii]ib'ti-, imd mainly on tlie pedicle. 

The eleventh lias a cunipli-te fnci-t on ilii- bitsc- of iwh pislicle, ami none on 
the short lntnsvcr»e pt^Kt'-vw's. Tho lai^' Irndy \* (ilrmpttt'd Iransversi'ly, iiiid the 
itptni>n;< priHc^-' U nliort, )ilout,and horizi>iit;il, thns approaeliiiiu tbi- Inniluir ty|ie. 

The twelfth n-sfmblf-!i the lumbar still monv in il^ IkmIv, spinous aii<i tninsvcnw 
processes. The latter are short, ami present external, superior, and inferior 
tiibervK-!*, rorresponding to the traiisversf, nutnimilhu'v, an<l avcwwory proec^tta'^ of 
tin- lumlinr vertebrae. The inferior articuLir pnM>e-ssi^ look outward, as tn the 
luinlMr. As to faeets, it resembles the eleventh. 

All ihe ihoraeie veriebne are thns seen to have either entire or dcmi>facet8 
alxive, and onlv the firnt eight or nine have dend-faeets Mow. 

Variety. — Tlie t«nth vertebra occasionally has no taoeta on the transverM 
prooesses. 

THE LTTMBAR GROUP. 

The five tumbar vtrlrf/i\r (Fip. 140) are cbar.ificn/ixl by their lai^ size and 
the absem-c of costal iirticnlar fiteels. The bwlu" Lire i!iing:ilcd transversely, and 
|Are fliightly deeper in front than behiml from the third down. The iamina are 
strong, slJort, and deep. The 
«prnoM« pr»cct»fe arv thick, hori- 
zontal, »nd broad from al)ovc' 
downwunl. Tho slender sfj-ealled 
Ir'ttuTcmr proivitio-n prujcel oiit- 
wanl from Dm* [tttliehv in serial 
line with 11h- lower ribs. TJn'V 
are in n-aiiiy costal proct'^o.es, and 
sometinut) are ditvelopeil into Inni- 
liar ribs, especially in the first 
lumbar verlelira. .Vt their Ijasef, 
dorsallv, a -moll process is seen to 
project dowuwni'd — ^Ihe wcwwsorv 
tubrrrU or rudimentary trsinsversc 
process. The facets of the guprrior 
arliettlar proeesimi arc slightly 
concave, aixl look inwani luid 
somewhat backward. Snrnioniit- 
iup their ixiKterior border is a 

lubnvle, the imi mmi/li tni proceiw, which corresponds to the superior tubercle of 
tiie low<'r tbiivaciu v<'rtebr<e. The facets of the mfi-rwr 'irtl'-fifur firiifrKivM look 
oniwanl and slightly forward. They ai-e nearer together, and are embrai^^l by 
tJie su]ierior processes, but not bo closelv as to prevent slight lateral and rotatory 
movements between the vertebne. Tlic /nriimen is triangular ami lai-ger than 
in llie thoracio vcrtebrie. 

The fifth liimbjir vertebra is trnnsittonal, approxinmtiug the sacral, lis liody 
is large, wt\ij;e->^!i(HHil, and much ihfper in front than liehind. To nrtienlate 
with the first «neral vertebra its inferior arliewlar pr*»cesscs are as wide a|>!irl as 




fir.. 140.— LiUDlMir vertclini, vicwtil from HboVF, rTMIul-t 




ISO 



THE BONES. 



the ^n|KTliir. Tho trnn^vcrw proctwca nrv lai^-, Immtl, ami cniiicul, M)invtirac« 
articiiliiliiif; willi tin- «irnil alu-. Tli« i^piiioiiK pnwTw t« tiluirl. 

Varieties. — In a snnill |HTwntiip' {(wtiniiit'-il al 1 jut ri'iii.) hI' i-iiws tlio fifili 
Iiimhiir viTtchni \* so Hcgitirnt'-il into tw" imrrn ihroiijili rlic siivli that tin' rlontal 
Begmciif (w>n.*ists of Itiiiiiiiif, M]iiTio)iH ami iriiii-inr nrticuliir (iiijcosftcs. 

Varieiieit n» In the ShiiiIht of }f<iriiliU' IWh'hnr. — TIic rt'ivii-nl vprt<-bne nre 
remarkalily fifo from \'ariation in mimher, not nnly in man, hut in all niamnialti, 
with two or thr«> exceptions. Variation in ihe minit)er of tlioracii" and lumbar 
vertebnp may be n?ci])r"oal wlien it depc-ntU iiju^n an inci'easc or (lecn'a-'e in the 
nnnibcr of pairs of lower ribs, causing an incr(wc in the tliornrio and a decrease 
ill the Itinibar.orthe reverse. Whether the extra vertebra be thoracic or Innibar, 
the ehiiraclcrs of this vertehm ari' more those of the lumbar tyne. Or, again, 
Uie number of movable vertcbni- iiiuv be iticreajred or decreajied bv one, causing 
nn inorease or decrease of one in tliu thorueit- or InmlHir proup. This iucroKic 'in 
usually in the lumbar s<.'rii'», the lower one of which may be jnirtiy unitcfl to the 
eaenim. 

TeUJe slioiciw/ (hr Ckftniiirr« of Ihe Typical Veticfutc of Ench Group. 



I 



PedlclM: 



Tjunlnw: 
Tntiu>v«rw pn>- 



jiro- 



OmUtL 



Smdl, tnumrrwlj rinn- 
g«t«i]. Slotiol ilowiiwiinl 
and forwurii, I.i[>pL-il Int- 
cmllj-. N" KHiul fm^rW. 

PiiMi •iiilwnril and Viach- 
wurd. Nuttliw uljDvp 
and below ncnrlv k|uii1. 

I^inir, AjriKicr. lf:>ltciinl. 

Sliurt, ittn.<n([. Iiilid, and 
iipnrly liciriicintal. 

Shell, iii<-'i(l<T, 'Hivcdjil 
uutward unil furwiird. 



TlkOfMto. 



Coatnl proceai: Slender, lint, onilivd tu (he 
I VRftclini mid lmn«i?crMi 

SaiwriLir ■rticii- KInL I>ir«.-t«i] ii^iwunliuid 
luptunL-sHes- sliglitiy bwltwnrd. 

liifrriiir nrticii", Flal. Wn-di-d downward 
Inriirocirwiii, and slightly forwnrd. 

S]un:i]Curnniun:' Lai^ lrUn|ru1>r, wide. 



Hciirt-iihii|ipd lK'P|Jcr be- 
hind. Kcarly njuki 
lmii>-i'<>nwiy !uid niiloru- 
IHRteriurly. (.'ostul riicela. 

I'vt backwnnl IiifiTior 
tiiilclKW du«|H'r ihnii itii|H>- 
rior. 

Bnnid, dwp, imbricnicd. 

I>iiiiK> pnijiflilv; dowiiwnrd 
imd ovcrlaitpiu^'. 

l-imn, i-troiiK. I'mjivt cm. 
ward uiid iMckwiird. Ar- 
liciiliilc witii tuborcIcB of 
ribs. 

A aeiNUHM himn {L «. m 
rib). 

F'liil. Dirri'tod biii-kwKrd 
■lid >>Hghlly oiKwurd. 

Flnl. Iiireiiwi forward and 
alighlly inwiud. 

iMnttller, ciivulttr. 



Lumbar. 



l.wgc, cloiigaicd (rnii*- 
vormely. So conn) faoein. 



I'lwi backward and tliithily 
oltttturd. luferlcr aulcliM 

Sliorl, di*p, niid ihirk. 
Qii:idrNI<-. Iiiirin.tiliii ; of 

tiii.-ditiiii leiifflh. 
KudinK-iiUiry, a» "accw- 

Borjr prucavi" 



I 



<h«ifled to vertebra. Flat, 

Ihhi. Cnllctl Iho " irntu^ 

Ti-pw ]irw»«-" 
Sliglitly p(>iiravi>. Diracliil 

tiiw.inl anil uliffhlly back- 

WMr<i. 
Bliyhlly ccmvei. liin-cicil 

oulwnnl and slightly fur- 

wiinJ. 
Lnrccr ihnn in tlic tlionide. 
_TH*njpjl »r, wide. 



k 



The one distinguishing feature of a eervli^l verlehm is the tiwlfi-tmn^verse 
foramen; of a thoracle vertebra, the artieular facet or dinit-fiuvt on ihe body; 
and of a lutnbar, the abM^'Wce of both of these jieculiaritic.^. 

THE SACRAL VERTEBRA. 

These in early life present the elements of five di<.|iiiot vertebnr. but in lh« 
ftdull tiiey avr iiriittil into a curved triangular bone, the on mcj-utn, m called fmni 
ltd list.' in wic-rifiee (Figs. 141-143). It articulates laterally with the two hin- 
bones of the pelvic ginlle, and thus completes the |>elvis behind and gbove. In 
the ereet (MMiticiu (Ik- wicrntn lies oMi(|iiely. it-; upjK'r -lUrfaee or i>ase incliuMi 
well forward. an<l articiilaling with thf fifth lumbar vcrtebni. 

Tin- (tacnil vertebni' dcfn-a«- in siw fnim above ilowuwiinl, thus giving the 
.sacrum a triangular sliajxt, wiih a Ija.'^-. n|>cx. veiitnil, dorRiil, jiiid lateml surfaces. 
Its se]karate elements iirftifnt ma^l, if m)t all, of Ihe (T>m|H>nent parts of the 
movable vertebra ; am! the diffi'rent jHirtiimN of thi- sucnini are best understood 
when studied with reference to thew parrt. 



TBE SACRAL VERTEBRAE. 



121 



Tlie ha*f nf thfi snonim, or Ihc iiiipor mirtaoe of th« first wicral ven(?bra, 
|xe9eni)jle!« tliat ut a liiiiit)iar vertdira. I'lu- liir^e, irau.^verstly oval u[>pcr aurfuco 




Pin. 111.— Tln'«*eruin, vmlral riew. (TtrtoL) 

Lcf !h<> body extends forward to meet its ventral surface at the pronuyntory of 
lih« itat^ruin, whioli forms the dorsal boundary of the pelvic brim. Its snjierior 
artindur pronxara, widely trepiitrtttx), l>>ok backu-art) and iowiird like the lui)il>ar, 
and have well-marked niamtiiilhiry proccsws. The _/"'/<■« itwji is trianjfular. ()u 
J the sides of the Innly we see the smooth n/w, or wings, on tile up|»er surface of 
tthe lateral mama, which are formed by the fustou of the transverse and costal 




.TMiao DOaMk 



*HOL( 



Fra. ItZ— The Mctuui. domil v1»t. |T«*iut.) 

t on either side. The alie are continuous with tlie iliac fossne on «ncJi 

The apfx of the sacrum, dimoted downward and a little forward, is fnrnic^l 
by tlio transversely oval inferior surface of the body of the fifth sacral vertebra. 



122 



THE BOXES. 



This articulates with the coocjx by mwiiis of an inten-ertebra! disc, which in 
advancpti life often oesifieB. 

Tiio renlral mirjnce looks (lownnanl u« wfll as forward. It is concave ver- 
tically, less so transviTsely. In the* ii-mule it it* broader, less curved vertically. 



mOMOllTO^T 




Tin. 113.— Tlunmctuin. lu Icit tMe. (Alblniuj 



and thf iipcx is dirocti-d more iihli(|iioIy bm-kward. The five bodies form the 
midiilc ol tbif* i^nrfact'. The ii|i[K'r Iwo are largt', the lower three '■muUer. 
'Y\wy im' .se|JiiniU'J by fotir InmsvcrNi' ridjres, the nM^ificd interverti'bral dist*, 
which arc licnindiil kilonilly by tin- f>iiir jiaii-n of vi-nlml Mtcrnl /nrttmihii, the 
vi-ntrjil i)jH^iiiiip> of ibe interviTlfbnil foramina. The ventnil Oniiiniiiii 1iiiii»iiiit 
till- vvntnil ilivi-nions of llu- (ir^t f<Hir ]mirs uf sacral nerve.-, ami li-iul i-xteniiilly 
into igroovos in ihi- lateral ma!«ies, whirb in fmnt eonwiit "if i\m-tl fusiiil jinM-t-sw-s. 
The ihimttl xur/ace i> eon vex, rough, and narrower. It |it'(>eiits in the median 
line the spinous piiK«sfte-s of the three or four np|Kr vertebne, nnited into one or 
two ridges by ossilieation of Ihe c-onnectint; lipanients. 'I'he tif'lh sjwne always, 
the fourth nsually, and all rarely, art^ waniinp. On either i^ide i« the ttacnil 
ffroovf, ct>ntinuou.-< with ibe vertebral giiH)Ve above, and formed bv the ankvlosed 
lamin». The laniime of the fifth vembra always, and thope of l^ie fourth often, 
are inoomplete, leaving a Iriaiijfuhir gap in ihe Iiiwer <)oi>al wall of the spinal 
canal. The lower mar^ritis of Ihi^ pip are proloiiKitl down as two tubercles, the 
*acfvi/r«mu« ("Iiorns"), which repre>ent the inferior articular procetises of the 



THE COCCYX. 



123 



fifth sacral vertfilira, and arc counoctod by ligsiucnts with (be coccygeal 
comiia. 

On tiich M<ie of the i^cml ;rr<K)ve is a series of ^ma\\ proniiDcnot-*, th« »itit> 
viar and mammiilary pi-Qi-cmin, "ifiw rated from a more external ^-rifi' of Inrp^r 
cminvi>ci-», tht traiuwr/ir in-oct/aics, by the four (hrmf Mtnitl fca-fmihin. T\n- latter 
an- iipjKxMtc to, hut "nialler than the veutral sacral foniminii. The four sacrni 
uit<T\-<'ricbnd f^iov<!s on wn-h Mv p<i«i oiitwuni an esiiiiiU na fur a.* ih** latcml 
nia--*, wht-n- thi-y hiftiroalo and \ia»» forwnrd nnd backwurd lo ihe venlml hikI 
d'lruil fonimitm. 

Ttuu ]ian of the l>otn? exicriml to thi- foramiim constitutes the /n/cf-ii/ ihtw, 
whost- lateral surfaces are hma<l i«»d ihiek above, narrow below. The umwr 
bnnad part of each lateral siirfait^ presents in fmnt an uneven articular surface, 
calU-fl the imrifatar mirfiu-e, from its ear-like shape, wliieh ariieillatos with the 
iliuiD, and behind a rough surface for (he atlachnient of the iio-ierior sacro-iliae 
ligaments. Below this the narrower rough niai^in gives atlaeliment to the «cri>- 
sciatic li^nients, and ends in a projeelioii, the iuffrior liiUiiit <tm/li', below whieh 
there is a notch, converted iiit<i a toraiiien by ligumeiits from the cocca'x. 1'hrongh 
this foratiieu (isu^ses tho anterior division of the lifth saenil nerve. 

The SQicral »piHat canal cun'cs uikI iiurrowr with t)ie Imiie. It is triangnlar 
abow on transverse section, flattened or >(cmihin:ir l>elow, and lodges the h>H'er 
«Dd of the cauda equina and titnm lermiiiale :nnl the spinul dura as far as the 
thtnl vertebra. 

PecnUaxfties and Varieties. — The seeond and third sacml verlehne represent 
th'- ?^ii-nini of nimnnialK, the f<nirfli ;ii]d tit'lh tlie first tivo nitulal vertebra?, while 
l\v tirit repres».'nif the Mxlh hiiiibnr of in-wl ijuadriipeils. This explains the 
<KH.Mti>i'Mial iHidial or eoaipleie seiuiratinii, and the tnuisifional nnd [Ktrtly ttmibar 
<!hara«'ler of the first Mieral, whii'li is not uueotnition. The liii^' miiiibiT of saend 
veriehm; in man is assm-iauil with his upHjrlit [wj.-ition. The sa<Tum ^omctiineif 
cim.-'i^^ts of >'ix -K-jf incuts, niuri- niri'lv of onlv four, in the former iuKtanee the 
flr^t tMcevgi-al is ii.-<ually iiieluded. The l)n-a<ltli of the saentin a« conimn^^l with 
its length is retnarknhly great in man as eomjiared with mamnmt.s, nnu (vpeoiiilly 
na ill European sptioimens. 



THE COCCYX. 

The poccyj- (" cuckoo's beak ") (Fig. 1 44) consists of four, but sometimes of 
five aiid rarely of three, rudimentary vertebra.'. Thc«* consist of little el-e than 
btnlieii tapering in size from above dowii\«ird, m> a> to give the bone a trian- 
pibr uutliue. In advanced life ihey are unkyloKcd togctlier, and oftentimes 
with tlic ■•acnim ; btil before then, e.<|>ceially iti the female, (he first it movable 
on the succeeding three and on the fifth sicntl, with which it is united by libro- 
eartilage. 

The first coccygeal vertebra presciiis vestiges nf n ncttiral arch in two upwardly 
pn>jcl^ing rtini'ut and two liit<T,iIlv iinijoi'ling liiinnrrivr 
i.r mutiil pi-otv/nrn. The eorntia, repn-seniing jx^lieles 
aiul sii|M-rior articular proeessec, toniplete the la.-t iiiter- 
venehnd fonimiiia for the fifth s:i<ral ne^^■e- by their 
iiitini-ction with the sacral eoriuia. The transveive 
priK'^'s-es Cfinipleie the Hotcbe- below the latenil meral 
angles, which arc converu-d l>y ligamentous tissue luto 
thi' fifili anterior sacral tomniina. 

The aecoBd coccygeal vertebra preseiit.f two knobs 
diirvally »ik1 two latemlly, vc»tigi-s of the iicunil aruh 
and costal pmcvsMSi, rf^iieclivi'Iy. 

Three gr>w)V(iiwpnrale ihi- four bo<!ies. Tlif ventral 
Mirfin-^' of iIk^ eoecvx i» <'oiu-,ive, is closi^Iv ifhiled lo 
ihc rectum, and infertorly gives insertion to lite levator an! muscle. To the thin 




Fin. IH — Tl.l' C0CCT», TCBtnl 
■UTli*r«. <T«i(uM 



m 



124 



THE BOXES. 



)at(.>ral borders are attached parts of ihe ooccyceus muecle and preat sucro-st-ialic 
lieatnentM, to the tip the external sphincter aui, and to tiic posterior miHiioc mmv 
fibrt'B of the gluteus maximum. 



THE SPINE AS A WHOLE. 



H 



The vfrtffjral or «plnal rohnnn (Fig. H5) is the wiitral axis of the skeleton, 
and ocH'iipira ihe nieflian line ol" the trunk dorsallv. It supporta the head supe- 
riorly, the ritis laterally, and through thera the weight of the upper cxtremitie*. 
It tran-^niiti the weight of these parts to the lower limbs through tlic liip-boiic^, 
with which the sacrum articulates. It also encloses aud pn>tect« the spinal cord 
in the bony spinul canal, which is provided with a series of thirty intervertebral 
fommina on each side for the exit of the >-pinid nerves. The average length of 
thespinefnim theatlas to the tipof thoeoecyx, following the curves, is twenty-eight 
iiiclioti in the male aud twcnty-sevvn inches in the female. About one-quarter 
of its Ivngth is made up of the intervertebral discs. 

The profile virw presents four curves, convex forward in the eervieal and 
lumbar regions, baekwiinl in the thoracic sind sucnd. The thonieie and wiernl 
curves are primary, and »Keiir in rlie early embryo, aeeonimoihiting Ihe (horaoic 
iiml iK'lvie viscera. They an- liuc lo the KhajH' of the bodies, while llie w-condary 
ccrvieiil and liiinhjir eiirvc:^ are due largely I if nol entirely in the eervienl) to the 
shape of the intirverU-bnil diw,<. Tlio hitler Iwn curves are onmpcn.'^itori' to allow _ 
the ereet posiiion, and are deveIoj«-<l after birth. Notiec that the upper threeB 
curves iwws impiTct-ptibly into oni- another, while the junotion of the lumbar and 
Binral i-nrvi-rt miikes an angle, ihe /iimhosaoral (or iiin-o-rcrffbral] frni/lc, which 
forma the overhanging firumonlori/ of the pelvis. Weight is transmitted by the 
Upper three curves and the first one or two pieces of the sacrum to the hi|i-boiics 
anil lower extremities. In the erect iMwitinn the chords of these three curves 
are in the same vertical line, the line of gravity of the head, which passes through 
the odontoid process, the middle of the Iwdies of the second and twelfth thomcic^ 
and the ventro-inferior edge of the last lumbar vertebra. The curves add greatly 
lo the elasticity and strength of the column, and thus break shocks and incri-a^c 
its resislancc lo Injun,'. In addition to these, a slight Intend eur\e. Usually eon- 
vex to the right, exists in the upper thoracic region, due probably to the gnitter 
miiseuhir use of the right side of the Ijotly. Pathological exaggerations of all 
the«' curves imiy exist, Sueh a curvature is ealled nmlumK (" curved ") if lateral, 
kyii/nMiti (" humpback ") if dorsiil, and lnnioHii ("bend") if ventral, the latter 
being UMualty eoniftensatorv t<i an ankvloseil hip. 

Tlie/rfiit( riiir present.-* the Imdies ol' the vi-rlehrre becoming broader from the 
axis to the first thonicio, and from the fourth thoracic to the sacrum ; and bocriniing 
narrower fnim the tii-at to the fourth thoracic, and from the tirst sacral to the tip 
of the eixMiyx. Thus, four pyramids are formed; but the total aurfiice area 
of tlie bodies steadily increases from above downwartl to the sacrum. The 
biKlies are widest in the cervical and lumbar regions, where motion is mmX. 
free. 

The rtar vleut presents in the middle line the series of spines, nearlv hori- 
zontal and alxiut opposite the corresjKindiug bodies in the cervical and lumbar 
regions, thus uUuwing free motion. The spiueii of the upper cervical vertebne 
■TO iiot readily felt in the living body until we reach the seventh, or Bomctimea 
the sixth, spine. The upiwr thonieie spincif an- eiiifily felt flubcutaneously, the 
lower thoracic and lumbar h-.-w so, for tiiey lie in the deep itpinal furrnw bounded 
by ihe inaKsei of mu.scles which oociijty the vertebral grooves- 

At the fiidoji of the spines are ttie rrrU-(,riif //ro«rw, bounded extenially by 
tho row of transverse proce»iiea. The floor of thetw grooves U formed by 



I 



I 




OSSIFICA TION OF THE VERTEBRA. 



125 



\-\h^ Liniinrp, conii4!oU-il hy ihe ligam«nta subflava, and by the arliculnr pro- 



'■cwwcs w 



ith tH 



i(^' Riammi 




in th*- Kiwcr [iiirt uf the ipim-, Tliu 
mjihinl ciinnf ii> Inr^r iiikI Iriniigiiliir 
in ihi^ fXTvicjil and lumtvar n-^oii», 
xnialli^r unit round in tliv llionicio 
n^on, ai)il .■•(ill smaller ami Batu-nod 
^ ID the Nocral nyioii. 

The wralce-'t iHiint tn the spine h 
fiiund l>inw*^n tin- wcond and tliini 
vical vcrti'iine, but the union <ii' thp 
c-ie and linnbar curves, or the 
plfih thoracic vertebra and ih<K*e on 
«ilber i-ide of it, is most liable to in- 
jury, for here :i fixed jmrt juin^ the 
DUist moviible, there is a ioiij; levtrrage 
">n Uilli fUlts, and the transverse M*idtb 
it ]vf» than above or bt-low. Notice 
[■that llie plune between any two vcrt*"- 
l^bra* is intrrniplcd l»y ilic iipwiird and 
f4lo\viiwnn) pmjix-tion of Ihi' arlicidnr 
|in«f*'«-s and other [wirts coiiriecied 
with tlio neural areh. Sinjple dixli)- 
«aii>m lietvfcen two vertebra: is, ihere- 
' fore, altnoet i{n)KMsib]e, uiile&i perhapn 
ID the cervical region, where the sur- 
{Acva of the articular processe!! are 
more ttearly liorizontal. Thin is Ix>rne 
out ill practice, wliere we find fraetiire- 
^li-locuiion the common injury, the 
piooesses or ncunil arch being eoni- 

Iinonly fractured, if uot the body 
Iteeli: 






OftsiScatioQ of the Vertebrae. 




Pin. IlEu— The 1|jIiuI cotiunn, riyht latorml view and 
donol view. (Tnlut.l 



The verlebrne are prefonni-d in car- 
tilage (Fig. 14(>)an)iiiid the notoehord 
vurenvlofling llie spina) cord. In inou^t ea.HCs three primary centres of osMliratioii 
occur— one on either side in the ni-nral arch, and one in the body. The former 
nnitc tojrether in llie median line dor- 



willy to form the arch. But nomeliiiies 
thi!< union faiU for a disiaiice, ei3{>e- 
•dally in the lumbar and sacral regions, 




ftJJA.B.t'tW-J.S.'f.'.i 

-I- \._,- 

h, — afrwiii I 

I 



1 







UTtULHblt 






Fh>. IU,— BvcIbiiIde nf (wfinrnilon in tho crntl- 



riD. IIT.~-OHtfit*tl«n at « thnncic Tvrtrtin. (AfUr 



leaving a gap llirutigb which a spina bifida may occur. The part formed bv the 

-ossifie centres of the nctinU arch constitutes a varying amount of tlie lateral and 

'orsal nspecw of the IkmIIcs (including tlie rib feccts), 6c|iumtcd for u Hme from 




126 



THE BOX£S. 



the rest of tbe body by llie cardlagiuoUH neuro-central suture. At l)iri}i a 
vertebra oonslslfe of three osaiBe*! parts — a body and ihe two lati^ml huUe* of 
llio ni-ural arch — cuiiiiectcd by cartilage. LattT five epiphyfieitl eeiitrtii ii|i[x.-ur — 
tliiic of which form ti|w for the spinous and trausvei-se piiDothwen, ;ind two 
fiiriji tliin plates on the npi>L'r and Jowcr surfaces of the b(>di&». Tin* luunimil- 
lary prix-es.-ie.-. of the Uinibar \ criebne liave each a stuall cenln'. 'I'hv civ^lid proc- 
esses of the sixth and seventh cen.'iral nsimlly, of tlio first Inniltar wnictime*, iiml 
occasionally of other cervical vertebra?, axe formed from se|>anite centres. TLe^e 
may remain separ-.ite and become cervical or Umibar ribs. 'I'iie various centres 
are not wholly united until about the twenty-fifth year. 

The (lUais i-egularlv has three centres — one for either half of the nonnil aivh^ 
formed by the latcrul inji^isew and thi> dorsji! arch, and the thini for the vciUnil 
arch. The («■/# (Kij;. M.**) ()s>ifici' much like other vertehnv, bnt it* odonlnitl 
procciss liaf Iwo liitcndly pliured eentrov, which unite together, anil later with ilic 
Dotly i.f the axis, though the wntn: of the intervening cartilage persiiits llinmglt 



I 



tlPMVmO^ DDOhTOlD 




Kill 






K>, 



lOWlRlMl~'im' i""™ 

Pin. 14&— Omincnlliiii lit III* >xl(. (AfUr Tea- 



utf Ml nun 







tvnicuiMtPirxiMi 



Fl(<. 1(U.— OtKllli'Dllim •'! till' ■nrniin—liotlioiital wc- 
iliin thmmtli iir«t iilcM iaiiitT«iiiii j 



life. \n epiphyseal centre also appears for the apex of the odontoid process. 
Tlie aticrwrn (rig. 149) also ois^ifics cirscntiidly like other verlebne, except that 
there lire wjMirHteccMlrcs for the oost.il pn>cew-es of tbe upper three vcrlchrje, and 
the miriciilar iiriicuhir siirfiiOA's hnvo two wcoiidary cenlre-i each. The interver- 
tebral disc* ossify on tlie surfnire, but not in ttic <.-entrc, from the eielitorntb to llip 
twenty-fifth year, from l«-low iipwanl. The f'>ri-i/.r is eartihijiinoMs at birth, and 
(■acb segment iiiw commonly but one eentn-. 'I'lie lower lliife luikvlose before 
nitildU- life, and these witli tbe fiivit still Inter, whih' bony union with the Mierinn 
lHlunK!> to mlvanci'd aj^-. 

Variations, — Two or a single lateral eentre may exist in a vertebral boiiy, 
forming a divided or a half vertebnt. In the fifth Ininbar vertebra the neiinil 
arch has ofren four centres. The pairs on either .side may fail lo unite with ea<'h 
other, eansing a si:-|»aration of the lamiiue and inferior articular prriee,->.ses from the 
pedicles, etc, 

Serial Horpholonr of the Vertebra. — The siniilaritv of eonstruetion of the 
vertebra.' in each region of the cnhimn is evident from the studv of their develo(>- 
mcnt and ossification. Ccnlm or liodies arc prc-enl for all the vertebra in man, 
but that of the atlas is disswiatw! from ils neural arch and joined to the biwly of 
the axis as tbe odontoid process, Nothiiiu need l>c said of the neural arches and 
spines, except that they are ineoiiipletc or wanting in the lower sacral and coccygeal 
teftions. Tnc articular princesses are not impurtunt morphologically ; but the 
upper thn-c are not homoloKous with other artieiilar prtK-es^ics, but rather with 
llie hitenil par's of the bmlies formed by llie neural arehes. Tbe ti^insverse 
proee«ses, so calltHl, j>rcseiit mon- ilinieiilty as well iis interest. We find two 
transvers^'ly direeted pr<«T.i.-n'S — a ventitil or costul process nn<! n dornal or Inins- 
vcrwf proei-«. proper. They present ihemsilve.-^ in the simplest form in tbe 
llioracic region, where th« ventral or costal prm-ess is a wiinnite rib. which by 
articulation with the transverse process enclases an arterial foramen, the coirto- 
transvet^e. This foramen is seen also in the cer\'ical region, where, however, the 



I 



THE STERXVM. 



127 




ivliCD, in ihf luwtT rcrviciil virubni,*, lh«y furni M'giainiU- wi'vicul ril>». In tlio 
InmlHir ri-pjon the i>»«t'>-lniiisvt'rM' riiraiiu-ii U iii(li<-iiti*<l oiilv bv ii proiij) of liolos 
ul t!jc I»!i«' of mill )«'l\v<i-ii iIm- iniiinVfrse juinfrw ami llic iwirtwjMtrv tnbfiX'U*. 
TIr- latttT n-i)n5«'iii« tin- liji ul' lh«- nujijinwiMxi dor^tly ^iciintcd tmiii'vcrw; 

Iinxw^*, wliilf iIh- tni lis vers* [nix-i-io repn-senls a ootilal i>ro(;c.*<, uiiil in ilic first 
uinimr »4>[nctinic-'< (^xi^tn an a n^'parate liiiutmr rib. In iln' iipiior thnf or true 
^(■nil vrrtrbne llif largo veniral costal processcii ami \\w ilorMitl IranHvente 
jin-cejwt^ iiiiiie to form the lateral maiwi'n which articiilnio with diP hiji-lionr^ 
bv in««ii> of llw'ir cdiial ]Mina. The MinDi miliary processes (lie?.! ^cn in rhc 
lanihar an*) lowir (horacie pppioniij are riitlimciiu «t tfie niucb-eloiigaied articular 
proce^ikes in some aniraaU, as the dog, etc. 



THE THORAX. 

Bft*iil<>* tlic tbomcifi vortobiw alrpa<J_v (Ipscribetl, the skoleton of the thorax 
bn^Mt-plate ") ooo^sts of the sternum, rilt^, and costal cartilages. 

THE STERNUM. 

The tttmvm nr hrwxi-ftour (Fig. Io<)) is a long, thin, Hat bone, Nitimted isiib- 
ciitKnc)ii-'<ly in the niiddle of the ventral wall of ilic thorax. It ih loimcirK-d 
wiih tht- ilioraoii- jkiiI of the vertebral axi?* b\- the oirlilageft of the first sovcn 
rilw on wM'li Hide, and, through the attachment of the clavicle, it connects the 
:<hoiiIder<girdle and the rent r)f the nplier extrcmitv with the vertebral axit-. It 
lies obliiinelv, =o thai it« lower end is further furwani than the upper. The 
DpjK^r end corresponds to the lower border of the second, the lower end to the 
tniftdic of the ninth, thoracic vertebra. 

It con^i-iits of three |wrtH, derived from six original segments. The firpt e»m^ 
nienl, or iipjKT (>art, remains separate through life as the manubrium ("handle") 
or pre-sternnm, united by fibro-cartilago to the succeeding four segments which 
fomi the fflatiiotuM (" little sword ") or Inxt^ {mesti-stcnuim). The sixth or lower 
segmeat, forming the riphoh! or anti/urm ("sword-like") procrm or appendix 
(cnela-stcmuni}, n-mains cnrlilaginoiis und <Itgttnct to iidvancctl iige, when it may 
mifiify in whole or in pstrl, and .Tnkylusc with ihi- Imily, Ii \s usitally bent, and 
often perfonitcd, noteheil, or bifni. It ii''s in n pluru- brhiiul that of the Irndy of 
tlw sternum and the i'ariil:is;i-» ni' the sevciitli rib^. 'I'hi' Mti-riium \f liirigiliicliniillr 
convex in front, c^naive bi-liiiid, and pii'si-iils lnln^vlT^l■ Hdgi'^ where the Wgrncnts 
nnile. il coii^i»t.4 of Umimc <-aii<-i-1!oiis lissiit- with a ihin slu-ll of eonijuot Imiiu-. 

The mnnnbrinin forms theii(>|M-r bui-dfr nl'tluf ■■temiini, whiehi.'<dei'ply not<'hMl 
ID i1m; middle linUn-liirlrulitr n-itch), and prtwenls at its laicml angles two dt-nre»swl 
xurfiKTs looking upward, outward, and ba<'kward, where the clavicles articulate. 
On f«ch side of the nianubriiitn, a1 ihe widest jMirt of the siernum, is a rouch 
triangular surface fi.r iiuiou with ihi- carlihige of the liret rib. Itelow this the 
sternum rapidly narmws to tin- jnncii«n of the maniihrinm and the body, indi- 
cated in front by a pn^iiinent transvente ridge, which is easily felt through the 
skin ami is an importnni landmark. The second costal cartilages articulate witli 
snrfiices former) of two dciiii-facetn, one on the manubrium and one on the body. 
The third, fonrth, and fifth costal cartilages articulate with the sides of the btidy at 
the ends of the transverse ri<lges lietween the segments.' The sixth and *i'vcnth 
costal cartilages articulate with the shiping and narrow sidci' of the lower Keguu-nt 
t»f the body, the facet for the seventh carlilage being oompleteil by a demi-fiK-ftt 
on the cQsiforro process. The space* between the artieiiliir facets eorrcKiwnil to 
ibc int«reo«ta1 ifpaces, and narrow front above downwanl. 

' Tlic anicntation* of iltn MfeniKl, ihird. fniiith. finii. nnd tcTcnih cnrtilage* with two adjiiwtii 
rienutl ii < KntBi iti coKWpoiiil lo llt« arliculMioiM of lh» licttiUnf llicSr ril« wIlli iwn aiijaccni TBrtohnp. 



m 



THE BONES. 



Ma8^e« Altttchtil. — In I'ront : lau-mlly, tW |R-cU>riiIU tuiyur ; below the fft 
for tlic clavicle, the Blcrny-clfido-iinwtoid ; to ttic bast- of the CDi^itbrDi procoiw, 
tie rectiii* ahdominlH ; to tho siilcs uml lip oi' thi- cti»!f<inii prix,vi«s, tin; ajMtK-ii* 
rysis of tin- obliqiii^ iiml inmsviTw MhdiHuiiiul niiiwUv. Ikliitul : ucur the »iipcri«r 



IKTCHCL4VICU- 
UIB NOTCH. 



FOR aicowo CO>TU 

CARTIL4Ct. 



rOK thihb corriiL 




rON DflTICULATION 
CKHICLI. 



ran tmaT C«IT*L 



ron rouRTH covtai. 



roa rirTH cotTti. 

CJLHTIuaC 



_'nii aiitH COSTIL 



fOB (CVCNTH COST*). 

cmTILAOC- 



Pia. ISO.— T)i« atrrnun), reolT*) upML (RpalWhoU.) 

ai»Klf«, ihf rterno-h_vi>i(I ami •itcnio-thvrold ; lat«mlly, in the lower four segments, 
the trimiKiiliiri!< islenii ; to ihe cn*iforni iirocPt>», the diiiphni^ni. On thftwdi*: 
bctwocii the iiiccli*, tho internal intercostiui-. 

The t^k'rntini urtioitlate^ with seven, and occasiunally eight, costal cartihigcs 
and the cliivicle on vwit jiide. 

Tiie .iternnin is HiilH'iHimeiHW at the bottom of the Vernal groovf, which h due 



THE RIBS. 



129 



to th* lat'-ml prt)tnilll■nol^!; of the pectoi-nl miHoles, and is limited al>nve Ly tlio 
inu>rclavit>iil:tr tiotnli mid Iwlow l>y tlip inlrastornal <io|>ro»ion, tliie to ihc- promi- 
Donce i»f llif M'Vi-nlli tnii'tal cartilages above the levi'l of the cnhifbriii pOK-er^s. 
The pro|xirtioitiitc loii^tli of the hcrtly of the titornuni is greater in the male llian 
in the female. lU) avonifre k-iigth iit six inches in the adult mule, »uiui-whi)t lv«K 
in the female. 

Dtr<l<mmft*l. — The steniimi is formed hy the fusion of the ventml enrlilitjr- 
inoHs <-tKls of the tipper rili« into two latei-:il l>ars, whieh later fuse together 
iDoiully, exwpt in rare ojise;^ where a eleft Kterniini exicl*. 

Omificalion in irrepilar, Imt (iMUilly the firt^I two Hgnieuts pre-^ent a single 
primary cenlre, while twu liiteniliy plneed eentri'ii eonimonly oeciir in the sueeeed- 
iiig ^H-^ieiitK. By (hv tiiiliire of the latter to unite acrti«s the mediau line s 
ityiian foramen or a vertiwil fifeiire may be left. 



THE RIBS. 



f The i-ihf im^tx) extend in twelve pair." tiimi the thornctc verti-hm> in an out- 

I ward and forward eurve toward the median line in front. Thi-y flinn the lateral 
E wslb) of the thoracie tage, and are prolongi'd in front by the coital <nrtiWeft. 
I Aa the upper seven pairs of the latter \ia>^ to the rtternnm, the eorresponolng 
fvvcn iiuin of rib<^ are eulled ti-uc or Menial rilui, while the lower five mirs are 
called yfiAu' or mJfrtml ribs. Of the hitter, the lower two jinirH are e!dIed_^ort/i»_i7 
n'/ut, tf their forward ends are free, while those of the three (tail's nbov*- them are 
ermiHvtifl together. The lenpth of the ribs increases from the t!i>l lo the eighth, 
and thenee it (iecreaiiev to the twelfth. The greatest breadth h fiinnd at the sternal 
end. 'I'he rilw« an- highly elustie, owing t« their slendernefs and curvature. 

Tlt« (Sneral charaotera of ^ical ribs arc best miirked in ribs like the seventh, 
near the wntre of the series. A fi/jiifiil rib (Fig. 151) consists of an enlargetl 




TUSCItCLI 



■RStC. 

FW. 1&I,— Tile elcbth rIbQf tho rlgbtdde vlowed frum belitnil. tHpalUlinli.t 

rertebml end, or head, joined hy a conHtricted neek to a i^haft. pre^^enttng a 
tnl»erele, an angle, and a sternal end. The /(«!</ hIiuwk tw<i iirlieiihir facets, wpa- 
rated by a ^^light horizontal rid(ie, to which the intcnirlieiihir ligaiirienl from thv 
intervertebral disc is attached. The facet* nrtiiiiliile with the two denii-tiii-clic 
on the sides of the btxiies of two eiintigiioiiH verlcbrn'. The l.iwer facet is iho 
pnmnry and larger one, and artii-nlute" with tin- verlebni which eorresjwndd 
in ntimlxT to the rib. and it is the onlv fiieei when' there is but one. The neck 
i» the [Hirt l>clwwn ibi- head iukI the tubercle. It ia rough behind and along the 
ttpiBT and lower bonli-rs for ihe cost o-t ran sveivtf? ligaments, and forms the ventral 
IxMindary of the eoslo-tr;iiisverse foramen. The tuherele is divided hy an oblique 
gnmve into an inner ami lower smmith portion for articulation with the front of 
tlw- tip of the transverst! pro(?ess of the vertebra of the uamc numlKT as the rib, 
and nil outer and npper rough part for the posterior eoBto-tnins verse li^nmcnt. 
Tlw bodt/, or slmjil, beginning with the tubercle, extends to the cu])p<«l Hf^rtial md, 
which receives the eostal cartilage. It liS laterally comprcwied, so as to present 
inner and outer surfaces and npiKi' and lower borders. On iho inner iispi-ct of (h« 
inferior Imrder is the subcmtal ffroovf, whitih lodge* the intercoHtal ve!*i»els and 




130 



TBB BOXES. 



nt^rve. [t \a \x»l marked near the angle, und is limitvd above by a ridge which 
i« contiuiioun with Ihe iiiferiar border of the neck und gives attacbmenl to tlv 
ililenial iuienro-tlal milHcle. The inferior bonier, whidi w-j^ne near the angle, 
alfonU attachment to the external intereoiilul mtiK'le ; tin* vujicrior border to both 
inten^osial muscles; llie convex external mirliin' to various niuselc^. 

The shaft is curved on a vcrtiail nxt", or rallicr two ax^-s. The dorsil and 
sharper curve cxtemis from (lii.- Inii<l outward In the nni/fi; whertr the rib takes a 
Budiien bciid, tn front of which the curve is mere (;nuluHl. The curvature of the 
ribs deereases from the first, the most curved, lo tin- IweUlh, tile U«»t curvt-d. 




1 




ODOOVf 



Fin. IB!.— Thg alxUi rib nf Uio rinlii »iAt vIokdiI friim ibr nildiltv tltio of ih* tiMlr. (^pallctiolc^ 

The bnek of the an^le i.s rotifrli, for the ntlaclnnent of the illoeoxtalio muM-le and 
il!< uoward eontiniialion. At the lui^h^ Ibe ribs from the third to the twelith an; 
also tieiit on a horizomni axi.*, m> thiit if thev Id- nested oil ilieir lower Ijoniers ihe 
head end of the ribs curves upwanl from tin- anple.-. This curve inerea^.i from 
the thin! to the seventh, ami (hciii-r dii-n-iw-* l<i th<- twelfth. Tin- head end '^^ 
the first and twelfth bi'iid sli^lilly dowiitvard ; that of the second is in line wilhfl 
the shiift. This curve is somcliiTiis H|u>keM of hs a twistinj; of the rib «n itself. 
It increanc^ the obliiiiiiLv of iht- ribs as fiir as the seventh or eighth. 

Peculiar Biba. — The '/rjrf rib (Fig. 1S3) is tlie lea-itt obliotie. and is so plaeeil 
that it^ surfaces prest*nt upward and downward. If laiil on its lower surface, the ■■ 
head end does not bend up, but slijrhtly <]own. The -mall head ha*> but ai^ 
single fiicet, the nook is long and narrow, and the tubeivie and angle eoiiteide. 

On the hro:id hU]>erior siirliiee near 
the centre of the internal Iwriler 
is a rough murk, the ni^lcjir tubcnrie, 
the origin of the scalenus anterior 
niiiseh*. tt «,'(Hinite» a groove in 
front for the subelaviiin vein froin 
one behind for the snhchivini) aHcrv. 
Rehiiid the latter gnxivu an- aCtuclK-d 
thi' tirst digitation of the scrrains 
mtignuri externally and the sealeini>> 
niediiis internally. The subt^istal 
gntovc is wanting. The mpcohiI rib 
(Fig. 153) liiis no upward enrve of 
the liciid end, 1>ul it iii> almost per- 
fi-clly flal. Tin- u]t|»r jiurfaec lookti 
oblifjncly oulwunl, and ha' a promi- 
nent roughness for lln- sernUUs niag- 
niis. The angle i.- bill slightly marked. 
The Iciith rid has iisnally a single fiic^-t 
on the head, sometimes two facets. The 
^evenih rib ban but one facet, no neck or tul>ere]e, a slight angle, and u shallow 




Fin, IVl.— The nnl aDd mcvikI Hhi uf lliv tlubt *luc. 



TflK THORAX AS A WHOLE. 



131 



i>ubrostal pnx>vc The lu-tlfih rih n-.-icmbli-" tlic clpvcinh. biit li«w no miplr nn<i 
iiu -ulM-iiiiUil groove. It in flinrli-r, bi)<1iiiiiv Ih- riidiiuriilnrv, iiii'aniiriiig li-i>> llinii 
I inch in leogth — uri im]HinHnr puiiit in tiitnlmr iwi^ioii.*. It ^'iiht-r lii-s fl»i 
4in itH lower TKircler, or \\» liesul i-imI niiiy bend Mliglitly dowitwanl. lu oiiur 
surfiu» may incline wmewliiit dowrnwaixJ. 

Variittionn. — Tliirtei-n rilin mav o«vur on owe or Ijotli widfs, friini tlie preseuoe 
of a <tT\-i«»l or lumbar rib, Thp adiliiioiml ribn are cleveloiKKl from tlie costal 
lin>r<-«wT, «n<l un? ii^iially ciiort ami iniixrfect, especially (In- Inmltar. Vpry 
mrcly ii tliirtcfnlli tlii>nipic rib occwrii. The tenth rih may have no articulur facet 
on the tnWri^k'. 

(hunfitilioH. — 'Dii- rilw an- prefomiod in curlilafp-, and Imvc a r'iiigle primary 
wnirc nonr tho nngfc. Min-li later two cpipliyx«I centn-* apjiear — ^>nc for the 
l»Mid ajul on*' for thf iiihcreic — wliidi bwomc united to tht- rrat ol' thv hoi»e by 
the twenty-fifth year. 

THE COSTAL CAKTILAOES. 

Tile roritii eariUnffCK are bars of hyaline tarliliip' piv>lnngin^ (he rilw lowanl 
the »t^n>um. In direction the fiivt imsses pliglitly downwanl a.-* well as inwunl, 
^ ihf ^c-i^^ind i» hor7»>ntal, and the rvst, down to the eleventh, are direeted .'^uc- 
*<5«iively more and mon- iipwani in pa>'^in^ inward. Their breadth diminisheii 
from the fir«I tn the twelfth, ami ik greater iit the eostal tliaii at the nlenial end 
iif i-neh eartilap'. Their leiijjlli ineri-a-^i-s to the Kevcntli, and theiin' iK-comea 
irradltally lejw. In !«Ii;i|M' liny riKeinhle the Meniiil ciuK of the rili;*. The inner 
extremitieft of the itpjwr .-"even are eomicet^Hl with the Mtoniuni. the fin-t being 
fufted with it, the others artienhitcd. The eartilajres of the iip|Hr thn-e fulw rib^ 
are attadtcd at their nnlnrned, narrow, iiim-r i-niU to the lower bonier of the 
cnrtilaifipK next al>ove. The carlilnfn-s nf the flfiaiinn rib" are whort, and liave a 

[{■Hntinl fre*' end. Thi' lionh r.t and siirfaeeji afliird ultaehineni to mii.'^le^ — llw 
inner pnrtitee to llie triangiilariri sierni, from the -eeond lo the pj.xth, and l<i the 
diapliregtn am) iranrtven^li-t in the lower six ; the IwrderH to the internal inter- 
OKital:*. Tlie oostal utrlila^x represent iinossified epiphyses of the ril)-;ihalt». 
Tlie w)*tal caniinges are covereil by a thick perichondnutn, Ix-ncath which sttper- 
fieial owilieation may oeenr in advanced life. Thii' change occurs oiiite re^tlarly 
in tin? first aiOiiage, hut in the others less eominonly, at a later period, more par- 
ticularly in front, and more often in the male tluin in the female. 



THE THORAX AS A WHOLE. 



The bony thorax (Figs. In4, l<)5) forms an irreemlar, iruneated cone, com- 
pri-iwtil fnmi l>efore baokward. It is longer Whind than in front, so that its 
uptx'r .-inall n'oiform a|H!nnri-, or inlet, looks slightly forviard as well as upward, 
and ihe piano of ihe lower o]>eninjf, or baxf, also looks forward and do«n«-ard. 
Ttte marifin of the irregular liase is tl>rnietl by the two curved line;^ of the edges 
of the lower nix [lairs of ribs and cartilage)^ eonvciying lo the .\i phi-sterna) 
Junction, and bounding the subcottal nni/lf, tii the centre of which pinjeclii the 
cnsiform urucess. The doratil \rall, formed by tlie tliuraeie vertcbne ami the rile 
as far a^ the angles, is convex from alwve downwanl. The hiiekwiinl onrvc of 
the rib» fonn-i a broad furi-ow externally, the nrU-liriil ipymrr, nu i^eli side, 
U'tweii'n the anKtcs of the rib-- and llie vi-rtehnd Kpinei', which hitlgi-ra the eiv-etor- 
"pimv ntUHcle ;pv>up. Thi>f hjiek\;~:ird p(>>ition of the angle.-< of the ribs, about on 
n level with the thonieio >>pine--<, caiive" the f1iittM>ss id' tne hack which allows iW 
snpiue |insiiioii (■lianicterisde of man. The vnitrnl trail, formed by the niennint 
and costal e-ortilagtw, i« inclined tlownwanl and forward at an angle of 20" or 2^'^' 
with the vertical plane, and i-. imly slii;htly convex. The jwW«, formed by llie 
rilw, from the angles to the cartilagi-s an- convex from aliove downwanl ; much 
Bwire m from before backward. From about the ninth rib down thev slant 



132 



TUE BOXES. 




Fin. IM,— Th* ■ki'li'loii nf llic thorax, fhinl vIpw, iToliil.) 

inwanl. The interior corresponds in ehnj>o hi tlic exterior, except for the metlinn , 
pnijoctioii of the vertebral Iwcliea, which makes the nKxlian aiilero-jMHierior diam-j 




tta. tSt-— The nkvlctuii of Uii* chum, iliinal vl«w. iTp*iut.) 

eter lei*i ihaii that on pither sitk-, ami only little more than ono-half of the oorrc- 
Hponding external diameter. The lateral (rroovce forme<l l>v the forward pmjcc- 




Son of ttM- viTtcbnil butlkit und the IwHskminl ciirvatHn> »f tlw rilw loHgt' about 
a- luuirti iif till- Iniif^ »•« licK in frotil nf ii Iraiicvcrw iilaiti- taii^nl to the an; 
of ilie Umrui-ir viirvc. Thiis cinniiiiHlniKrc, n-pt'tlwr wild tin- witio tninsvonw 
diameter characieri!<iu' uf iiinii, tlirowis llio wtiglil liii'tlier back, ami niaketi easier 
the balanoe amnnd tlie !<|»iunl iixl> in Oiv <-rec( jKuiition. 

The rills arc nioiv and iimn; (>lil>(|uc fruni ab«jv<> <lowiiv,-ard as far as the 
wvcntli or lowpr— a faol due in jmrl to lln- incrtoninj; downward ciirvatuiv from 
till" liMid to the an^lc, ami in [wrt to tlie incrcawiuKly lowc-r ]>ociiioii of the trani>^ 
vvr«' processes of the lower ihoraoU- verttbne. Tliin iiicrt'si^ing obli<)uity of the 
rilis makes llic eleven inieroostal .niioees wider at the ridc!^ than behind. TIic!N> 
opacm contratri aK^i" s-oraewhat.iii front from the thiivi to tlie eiglilb. T1k-j' are 
widest in the upper three spaces, and wider in Hnsiuralion than in cxpintliun. It 
Hhorihl bo n-mt^'in bereft that the circumferetice of the right half uf the thorax ii» 
tmiiallv tiljont half iin inch lai^er than thai of the letl. Note itiat iIk' lowfr [kiI- 

{nblf *-nd >if tb<- ;;liiilioln!i is un a level with the lo«(^t mrt of tin- tifth rib. At 
lirlh the tltonix ni;»y measure even moro from bcfuiv bsickwanl tluiii t nin.-vprm'ly, 
KM is tlie vtL»^ Willi <|iui<Irii|io<U. This is due to the absence of the angles and to 
tlie Ie»!* curvature of the rtl»<' at this |)oriod. In the feiiuile tin- thorax in rela- 
tively shtirter, ami dci-|X'r fn>iii iK-fore buekward, atthoiij^li the latter diameter is 
actually h-iw iIl-iii in the tnnle- 

The ibontx is luhnirably aditjitiHl for the e"inbine<l pnq»oi>e of protecting its 
nonlained vistvra and tillnwing the movoineul:' iii'ccj'.'^iry in respiration. This is 
provided for by the pm-^;mv of ii niinibcr of s^'jutrati' bones, tlie ribs, which 8er\"e 
for protection, and earh of which liiu< » niodemte amount of motion. 

THE BONES OF THE UPPER LIMB. 

The skeleton of the nii|Mr limb (•<HHiiri.«tT (he irlnvicle and wapula, forming 
the iiectorttl an;)i or stluinliWr-ginlhr, tin; Iiunicrii." in tin- arm, the i-adtus and ulna 
in the forearm, and the mrjuil, nK-tacar|Mil, and phalangral Wtnes in tlie hand. 

THE CLAVICLE. 

The eiaekle (" lilll« key ") or mlltir-tMnr {Kig8. 15fl, 158) ]iiwwe« outward and 
backward fn>m tlie top of the .'•lernnm to the acromion prmw-M of the sciipiihi, 
•od forms the eonnecting link iH-twccn the trunk and the arm, affonlin^ u 
fidcrum in the move.nxtni.'t of ih« latl«r. It in curved like an italic/. U* inner 







Fm. IM.— Tti*i rltlil olaiiFle. u|ii>«T>iirA<v. ii<|ialM<huls.| 

Iwo-lhiids, prismatic or cylindrical, is convex forvraril liki- the tlmrax b<-low it; 
it« outer third. Battened from above downward, ih oomstve forward, eurre^pouding 
to (he hollow between the thonix unil the "biMilder. 

The mifurior irnrfnrr Is flat .ind hrond in its outer lliilxl, whero tl lit ovtirla|)|ied 
by the altitchmcDt of the iniiK'/in." Ix-hiiid itnd (lie ileltoid in front, with a .'•itl>cu- 
taneous arm lielween. In Uk^ inner two-thirdti it i^ rounded and subculaneoud 



^m 



184 



THE BOXES. 



tutternally, and raarkwl by llivattjichiiHriit of tin; xtcriio-cleido-inasioid inwrnally. 
The vrulrit! ifarfaer in its outer third is incn-ly n rwiigii border for tlie origin of 
thp di'lloid, near (lie inner limit ol" whiili is llii? drltmii tnim-ch; when im-s<-nL 
In \U iiniiT HviMliirds it !?< Iji-oiuUt, iind n>n)^li for llu- origin of tlie juTlonili" 
major nm^-cic, Tlic hijei-uir gitrfini- |»rc'scnl!« the mngh trapezoid tine, running 
in\v»nl and liackn'ard from ni-ar tho fi-uni of tin; outer end in ilie oonoiV/ tuhrirtf, 




Fib. UTi^-ATcu ut miiK-'Uluc HlUchmviit. U|i|H'r nirmii' of rit,'lii clmlclH. 

ncnr ihr dnrsil hnrdtr :it tlu; junction of tin* oiitt-r fourth nnd the inner thi^e- 
f<>urt!iH. Tliew i-»-«|(ectivelygivi' iiltiielniicnl to the tnijn-/oid itnd eonoid portions 
«f the floraco-elHvienlav ti^mont. lnt«runl to (he vonoid Inhcrcle is n Khaltow 
g^YKiVe for the ini*«>rtion of the xnltelavin^ mn.^cle. Neiir Ww ;«terual end is a 




Conoio 
TuamcLE 



■KntllL (NO 

Fin. 1M.— Thu rlKliI rUvirlv. utiiIi't aiirriiviv (!tiiiitti:>Tii)]i.( 



roiiirh impression for the rhomboid ligament wliich binds tho t-lavicle to (he first 
rib. Internal to this impression i-* a facet where the eliiviele pi ay » on the lirrt 
crystal eartilage. This faeet U continuous with the sternal fiift-t, and close l>eKi<)e 
it the .-itemo-hyoid miiecic U attocbed. The domal mirfaft, like the ventral, is 




PTu. Itu— An«a»r uiiiuiilar ■lUutliiui'iil, loner auThcv ol Hghi cIkiIoIv. 

merely a ronnh bonW in its outer third, where the lnii)er.iui* tnuKclc i« insenwi. 
In iw inner iwo-tlilrtl" it is bnuider and snnioth, and arclic* over the sul)eliiviaii 
ves.tt'U and tlie l>nieliial plexus. The niilrifjit foramen is n.smdly .-ici'ii jwissiiig 
oniwani near the mitldle of this surface, hnl -wmetime-i it is on llie inferior siir- 
faee. Part of the elavieiilai" attaoliment of the sterno-cleidt^maAtoid is found at 




THK SCAPULA. 



135 



» 



the nUimul end of this Biir&ce. The bon)<>r' wpRrating llu* tlonial uimI infvnor 
isiirfii«c» p(i«»i4:» from llie conoid tubercle to the rhonilxiitl iuipr^.-L^inri. 

Thv idrmai rml U iL'\|KiiHk'(l into ii lriunjj:<ilnr or oval anicutiir .■^lll■falN;, whioli 
|>la_v> ti|H)n thi; inli-ninitfitlur libroK-anilu^ between il aiul the -Icriial Ctwi-t. llit 
nuipti liimlent givv uttHphiiient to the ster no-clavicular and iiiterelavicnlar lign- 
nienti*. Tlw tin-omuti riir/ uR-^cnta nti ox-al iirlicular surlJice, elongated t'ruiu 
hffDre huekwun), und iK'veliod iiiferiitrly, which nrttciiliitva with the acromion 
prure«» of the M^apidA. llti n[>|x-r surfucc is uti a little higlivr ler«) tliau that of 
tl)V acromion. 

Tltccliivirle ha* mi m<tlnli«r%' wivity. hn( isci>ini"ii«at! of cjincellous tissue with n 
shell uf conipwt Iw^ne. 1 1 i" nmivor lew fiilxnitiincon^ t hnm^hont, but e)i[H'ciidly w> 
in tin- iiiliTiniiM'iiliir interval in-«r ilM ivntri-. KnK'tnrc L* verv ciiminon, cs]MX'i(dly 
ul the jiiDcliou of il.-t IW4i cnrvutiin-H (Inner t\vi>-lliinl» iiti<) untcr oiii'-thinl). The 
<daviele in loi^^ier, Htrouei-r, roii)rlier, unil inon- curved in tlie iiinle Ihnn in thi> 
femule, and on tlio ri^ht .aide ihaii on the lell. In tho nmic it iiIm) in<;lin(W 
slightly ii)iwanl as it rasses <mtw;ird. 

Ossiflcatioit. — '['hi' elaviele b the timt bom- to (i-wity. It ht^'ins in membrane, 
but quickly extends into the underlyiii); airtilap' of the preenmeoid bar. An 
epipliysit*, appearing at the eternal end between the eighteenth and twentieth 
years, ie tuiited to thi: ahstt about the twcuty-fifth y«ir. 

THE BOAPITLA. 

The iK*tp»ifn (("'iff*- 160, 162) is a liirgv, Hat, triangular hone, forming the 
dor«ul pun of the j-hiiuldt-r-girdlo. It rents njKtu the ui)i>tT aud back (Mirl of the 
thonix. and I'rom it i» -lusjiended the 
htnneni". It." !iurla<;fci are ventral 
ami dur*al ; it.* liorders sui>erior, in- 
leriuil, mid external ; ami from ila 
extcrmd angle or Iwaul, whieh bean* 
an Jirtieitlar surfano, pmjiH'ts tlie 
eorueoid prom-.**. The ^pine, pro- 
lunged into the aenmiion procefts, 
projwt'* fr'ini it.-* tiorsal fturfaeir. 

The Vfiitfat nurfaef, or r&itci; ppe- 
8«i]t« the Mt/Mfapular /o»m, a tleep 
eoncavity raost marked above. From 
ihe inner two-thirds of thtii fos»i, 
whieh i.s marked by three or four ob- 
liipie ridges, tlie ^ubscapulnri^ mus- 
cle arises. This fo««i is --epHrated 
fntm the inteniul bonk-r by u lim'tir 
area, which, with it« two trinngulnr 
expansions op]Kisite the npjH-r and 
lower angles, gives interlion In fho 
■«rrulii» niugnn.'i miLMde. Kxii'i-jiiiltv, 
the fo»<n \* limited bv a smootli, 
pruraitteiil ridgi; tlesnending fivim the 
iii-ail of thv hone. From tli^ narrow 
pHKive lurtwcen ihU ridge ami the ex- 
tcrmil Iwrder aru«> some fibres of the 
KiibMitpiiIariii. The convex ilorgut 
jrMr/''"vor(/of'iii»Msnne(|tudly divided 
by a prominent ridge, the tpinc, into an uppi-r iininller »upraapin<ni» fogta, and 

' Ni> olIiiT Iwhiw nwdi dowriplum. Tlie fluTicle ic oficji <Iiwribeil m huTlntt il"v« mrfncwj 
ml three botden iii it* inner twi-ttiirils, ni") iwo in llu cmuT lliiril. In iJiii l«n ninuiian or Jh»1 
•truraldf daMrihed coivlitkni the veiitriil Ixinlft id Bxixuidod \a it> mnltc for tlie alUchmmi of (he 9 
imvimlw nuOor intMcle. 




Pia. UO.-^The rlibt frnpiilii, Tvnmi viaw. (!fialukal(.) 




136 



THE BOXES, 



a lower largrr iti/Vrt^pmuiM/oititn, giving origin to the ifiipr!i!ipiiiatii!i< and i 
Bpinatii.'> mtibiel&s, rci<poctivvfy. Tiic two foside cotnniiiiiicutv uroiind the < 



infra- 
outer 




Til), mi.— Acvuur miuicutar MUchinviil, vvnlral iiirlkM of rtghl «0|>iilii. 

border of the spine by mcana of the great xtxipiJar nofvk, whicli corrusi>oinla to tli 
neck of tlic boae, and transmits the supnuicapular nen'e and veaeels from one fos«i 



■H 




Fjo. in.— Th« rtjbt impula, donal »lpvr, o^luhnli.) 

to the other. An ohliquf ridge niniiin^ fi-oiii IkIi>w the ffk-itoid fo#Hk to the verto- 
brul border just above tbe inferior anj^le ftcpamlt^ the infraspinotis fot^^a from a 




THE SCAPULA. 



137 



oatTOW t^axx bctWMii tliis ri<Igv and tfiv <;xtcnml bordt-r. Tlnm space Riven orif;in 
lu the Uti's minor mii.x-U- iiliow iiiiil tin- Urix-f majfir, on tin- UniiidiT jiiirti"ii, below, 
Th<- iiuuiHivc lmii)!iiliir njiiiif ii( tin- M'U|iiiIn it>iiiiiK-iiirH iiImhiI iIh- npiicr loiirtli 
of lljf vcrU'bml iKmlcr an « MituDtli, i-xihiiiiIi^I, tmiijrtilur scirfiiw, cuvitiiI bv u 
burwi itver which ilie lower [Ktrt of the trafK-xiiiti gli(li-.-> lo )>(' iiMrtcil iiilo » 
tulten-lc iK-yond. Fmra thin |>oiiit, [>roji-<-ting luiikwaixl utttl tipwuixi, .iii<l 
bpiNiiiiiiu; more ant) mon> «levalMl, it oxteiKL" outward and a litth- tipward to 
thv niidiltc of [lie nock of lht» t^capub. Thcitee it is oDiiiiiuicd forward and <nif- 
w«rd as ll»e Hal, oiiiidnitt' urromloit ("i-timtnit of the tJioulder") jiroci-itH, owr- 
haiitrio^ ihi' hhoiihier-joinl. The ii]>|kt ami lower eiiiooth, com^avc surfaces of 
till- :<p)i>e form part of tlio snpni- and itifniKpiiioiis fmiMe rebpertivelv. Of the two 
iiiiattnched borders, the siiort, ;'nioi>th, and eoiicnve rriernal bonlff arisen at the 
of^k of the scapuln, wherr it IkxiikIk ihe );n'ul iwupulnr tioteh, and \s cotitJDiioiis 
with the under eiirliuT of ihv aeri^itiiioii. The more prominent giibcutaneoiiH ffomal 
border, or rrf«/, U nmifh, broad, lunl siT|M-nline. Comment-in^ at the abiive-men- 
tioaed triangulur isurfacv, it [mum-k outwurd to become coiitinuoits with the rough, 




Flo. im,— Arru <>f miuf iilat Rltu^Iimiitil. diiiul MirAiwuf right gciipu la. 

subcutaneous u/jfter xurfitvc of the ucromion. ITie np|)er llii of the <.TC*t w con- 
tinuous^ with the inm-r bonier of the acromion, and to tlieni is atluehi-d the tnipo 
xioH ntiLwIc as liir a.-* iho oval fiiect for the outer end of the i Ijiviele, on ihe inner 
bonier of tlK' aeromion near its tip. The biwer lip i>t' tiie erei-l is Mmtinnoui* 
with the outer border of the iienHiiion, with wbieii it ftirm.-> iin angle, the itcromiai 
ntyfe, and from th«m the deltoid bike:< ori)^in. Fnnn thiN angle the measure- 
ments are taken to determine the length of the humerus. To the a|»ex of the 
aeromion is attaehed the eoraeo-aoromial ligament, and ils under mirface, con- 
linuo^u with the upper surface and the outer bonier of the npine, is smooth and 
civertHl by a bursa. 

The intrrnai or vfrtebrril bordt-r for base) is Ioeijt and irre^rularly e{>n\ex. 
Of>posile the eommencement of the spine it bi-nds more sharply, and here 
U iR«erte(l ilie rhomboidcns minor muscle, while below this an-n the rhomljoideus 
major is allnrlKsl by a fibrous arch, and above it the levator x^apiila: i» inserted. 
The Kii[irrior Imnfrr, >hort, sharp, and eoneave, extends from the i«n[XTior anj^lo 
to the twee of the conieoid process, where it proHeut« the «U]iniM:apuliir notch. 



mS ^^^^^ THE BOXKS. ^^^^^^^^H 

ponvortwl into a fyratncn bv the tran'-vt-rsr ligiinurnt (snmtttinKt'' !iy n spit-uln i>f " 
hnnn), Tlif IbninK^n tnuixmils the Hii|ini»<'Jiiiiilnr iiorvf, itm) front (Ik- ligEunciit 
and the ndjiWH'iH lnjnltr llic <)Tiir>-liy.ii(l inuwlf ariw-s. The ejintial or fixid'ny 
(loritfr U nnitc fhin, iiiiii jii^l hilnw iIh- glenoid fnwci rircsotiU a roii^h impression, 
from ivliidi i!n- loiijj IkmiiI of tin- iritvjw iirititrs. A iillle I»elow iliis ie> a groovei 
for I ho doisal arlerv of tlif limitiila. 

The long, rounded, lliick ii'/n-ior anyh is often calli'd fhr angle of ibe M?a|Kilu, 
To it^ dornal aspect iiumi> fibn-i* of the lutisMmui< dorrii mimelv are frequently 
attached. The fxtrrnitl atiyfr (tnweiiti^ ihi? Ifud, TOipjiortctl on a i-lijthtly coii«lrictecI 
/wcyt', and Iwarin;; the articular i/lfiuiul t-acUy for the hiuueriis. Tin- ^h-noid cavity 
b shallow and [K-ar-^hiipi-ii, until the narmw t-iid alxivc, iiu<) Iiideniiil ou it» ven- 
tral lij) above its ccntn-. Il looks ontward, ujiwanl. and fiirwitrd. To ilw rim ui i 
attached the glenoid ligament, which ihreiR-n.n the sliaUow i-jivity, and otilsiikt uf 
this the cnjiMidur ligament is atlaehed. The long head «f the hioe[n> urisi!'^ fruni 
its upper extremity. From the upper border of the neck the thiol;, slronK ora- 
coiit i"Iike 11 crow'!* Wak") pisn-eiis rises nearly vercieally for a short di.-<tnn(>«% 
and then benil:* slmrply forward and outward in front of, and more <ir les.- (KiniDtTl | 
with, the ui'romion. I'rom the tip of the proceK*; arif-e the short head of the 
bicepjs, the eoraco-brairhialis, and the c<jf.to-conieoid lijranient. To its inner Iwirder 
tJie iK'ctoralis minor muscle is attached, uud to itt^ ouu-r border the coraco-aej-omial 
ligament. Ita superior surfiice is rutigh, and iifTordf uttachment, near the base, to . 
tbo comeo-olavicular ligjinient (conoid and Ini[ii.-)!oid i^Mirtions). 

When the arm hangs by the '?i<ie the KTtipnla re^-tf^ upon the ribs, from the 
.lecond to the seventh inthwive, untl tlie inner end of its spine eorn'i-i«Mids lo the 
thinl ihoracie spine' or llie f\mcv below it. The distance between tlle^pil^eJ^ of the | 
vertebne and the vertebnd border nvenipet^ two inehe>. The tip of the eorncoid ' 

itroeess is palpable below the clavicle ami intenuil to the hnnienil heiid, exixrpt in ' 
at subject*. The dorsil i)ordcr of the spine, the iipjier .■■nrluce of the ncruiitiou, , 
and the lower part of the vertebral lM)rder are ali'o snheiita neons, 

OiwificiifMii oeeiinj in cartiliige from two primary and live secondary ccnipefi. 
From tile iiriniiirvi-enlres the biKlyand eoraeoid priM-ci^are fonned. Theeonieoid 
joins the body afiout the fiiteenlli year, when two eenti-es apjwar in the acrnuiion, 
which soon unite together and join the spine almiit the twentieth year, though 
sometimes this union fails, and the acromion is movable on the spine. Two other 
centres appear in the wirtlhige along the vertebral border, and another Iwtweeii 
the glenoid cjivity and the eorncoid jjrocess. 

MiirplwUiiiii. — The conicoid process represents the eorncoid bone, or ventral 
liiir of the shoiihler-pinllc of other aniniuls. Its ventral end has degenerated 
into ihe eosto-eonieoiii ligament. The glenoid fosMi is the ineeting-pofut of the 
(«raeoid and the dorsal signient or seapnia. The prevoraetiid bur of the shoulder- 
girdle id replaced by the clavicle in man, 

THE HUMERUS. 

The hnma-u« (Figs. 164, 166) constitutes the skeleton of the arm, and extends 
downward and slightly inward from the shoulder to the ellwiw. It presents, like 
all long l)one.4 of the limbs, an upper and a lower extremiiy and a shaft. 

The large upixr crtretnHif iucltidee the head, neck, and two tuberosities. Th« 
largo cartilage-clad heittl represents idjoiit onc-thini of a. spliere, whose vertieal 
diameter is slightly longer than the tninsvcrse. It i-- directed inward, upward, 
and Itackwanl, at nii angle of I'iO" with the axis of the shaft, to articulate with 
the glenoid cavity of the senpnia. The nnalntnirnl wrk is the slight constriction 
below and externa! to the htiid, to which the cansuhir ligament is attached. 
Superiorly, it is a mere groove between the hejid ami the tnberosities. The latter 
«r« separati'd from one another by tlie oonjiiienoeinent of thy bicipital groove. 
The great tutf^nuiilit, the higher and more dorsally placed, is continued up frum 

' And aUu tu ihc linurc Ii«[wcvu the iipjior nad lower lobM of t)ie luii);;. 



THE nVMERVS. 



139 




•UpaMMMT 



f 



Ji 



'Rein. 



1^. lU^Thc rlcht hiUDonw, from riew. rTMCiu.) 




[(IT. Kim: ■«•. ■«<¥. 
jTiT ooii, i>iam>i<ui 

UuplHltTOR 



^PLKDR ftdDLllttB DIQITOJIUH 

Fn, Ml,— Atmu of muscular ■lOchiDKit. Tcntrml 

Mp«ct or right hmncra*. tTuiut.) 




THE BOXES. 




Fio. Ml— The tIkM hnmcrni, few irlew. (T™iui. i 



Fin 1«T.-Ahm at iniucuUr ftlWrhmcm. itirml lUf- 
fuM of rlylil ImuivnuL (TWlut.) 



THE HUMERUS. 



141 



"iitpr ftiriaw fif till- fliaft iK'sirlv In tlir level "if the lieiid. Of the three facets 
_ _ _nT {lives iiisertiijii tii tlie siipr!U|iiniitUfi, the 

miilille to llic infnt'iHtiatii-i, .-tmi llie lower to tin; teres niiiii>r niitscle. The 
{ironiiiif-iit latniU lubfrtmi/fi \ito\iii t'orwurd anil ^iv<:r> iitsi>rtioii Ui the stibeeapularis 
niUM'le, Tht' mirgiviU nrt-t, i*o tilled fnnii the treijiieiicv i>f' t'niclnrc here, t»i where 
t]ie i-hatt jiiiiH ihc Hi»pi'r trxtn'uiitv. 

TIm' Hiiifi, cvlin<lrie;tl a(w>ve, iransverhcly (-xitandei! iind triii»};tilnr Iwlow, in 
twt>t(^i iiiw.iit) in df-^entJiiig. It prespute external, internal, inul ditr<al siirfanw 
»e|>araie<l by external, internal, ami ventral iMirders, The •jrimiat iiml hitfmaf 
boi-fUrn, lili^litly marked above, becom* pi-oniinent below as the fxi^rtuii and 
interitat supraeoiulylar ridyes, which dc&eend Ut the eontiyles. From eiieh of 
these an int^rauMiubr septum anHce, and froni thf upper two-thirdx of tli« 
exieriial ridge ari^tes the brschio-nidialU niUfM-le, and from it^ lower thini tho 
CXteiL'U'r vnrya rfi<lia]i!r lon^u. The rxU-nin/ horii'T exteiMb* <)ow li from the biiek 
of tin? great ttibon>^ity, an<l i* intvrnipttil near the middle of the ■thaf't liy the 
niriMTulo-spiral groove. The hilfmaf bortlrr (T(>itm)eiiee-^ above just lielow tht 
h«i<i,' and iK-ttr its centre prevM-nt» » ruuf;h impn-iwion, extending on to the adja- 
tt-nl inner "iirftoe. for the coniOMbniehialiw niuiM^k-. The mitral ftonler fitartii 
altovf from the fnmt of tl»c f^rjit tiibfiiisity tt»^ th<- oiiter^ip of the liici|)ita) 
gnH>ve,»nd ends Ix-htw in ibt- ridp- Ki-|Hiniiiiig the iriH'hlea and eapitelliini. The 

Cinlrnuil Mirftuv in il,-i iiii)H'r third pre>(--iit!« the veriieal hlrijiitti/ yjvKiri', which 
loil^TL-:. th«- long tendon ot th« bi<-e])^. Il--> two nmj^h ligin gire iuKertion, llic oiilvr 
tn the |»ectorali.i niajur, ih^f inner to the teres major lielow, and above to thti 
tati?»iinius, which i* also attaohed to the Hoor of the groove. A little iMdow (lie 
eentre is seen tlie nuli-teiJ /ormnen, directed downward. The r:xli-ninl nurfaff yre- 
^aXe'yw^X above the eentre a nnigh V-iihaped impres.-ion for the deltoid in^enioll, 
mimediatelv Iwlow wliich the Miiin'nln-spirnl gmovc ic 'i*'en *vindiiig dfiwiiward 
and forward after grooving the outer bonier. The hind or lower ptirtion of thU 
groove i^ Imversed by ihe muMruto-spiriil nerve and the sni^erior profunda vesseU, 
while \ts upper i«irt, together with the lower half of the external and internal ttur- 
toffeei and of the ventral Imrdcr, gives origin to (be brachialiH mniwlc. The dormi 



I 



mirfncf, unoijuidly divided bv the mnnculo-spiral groove, ^%'es origin above the 
hitter to tlie exttniul head ot^ the triceps, and 1 " 



lielow it lo the internal brad. 
The loiefF rrtrmtitif is tnmcversely elongjiled. Rattened from beJbre backward, 

id ciir\'ed forwiird. From withiu outwunl notice the following (lart-^ : The 
rominent inlrrnnl mmli//r is flattencfl and inclined slightly biickwani, forming 

nhullow groove behind. tmv<T>cd by the ulimr nerve From the fixinl of iti^ 
Mireniity arise the prontitor radii U-nn and the I'onimon Iciidioi of the KiijH-rlioiii) 
flexor muM'le)' in i\w foriiirm, heliiw which the inlenial l.tleral ligament i^ 
attiicbed. The urtitiifnr unrfiff is divitlid by a ridge («hich eorresiMind.-* to the 
iiilcivrti Im-Iwivu the ridiiii anil ulna) into a lai^ internal and a smaller external 
part. The internal jiait, nr IrwhUn (" pulley "), if- a pulley-like surface, griHivinl 
,tn the initMle, whieh articulates with the great sigmoid cavity of the ulna. It is 

liquely placed, so that it extends upward and outward behind, and its inner 
in desoends much lower ihati its outer. It is broader liehind than in front, 
ami itn surface forms three- fourths or moi-e of a circle. Alxtve it notice the large 
olifyniwn /••*»» behiml and the Hmallcr voronoiti J'omki m front, receiving, nrspce- 
lively, the olecranon process in extension and the coronold priM-esw in forced flexion 
,of the forearm. The external ]Mirt, the rapildlvvt ("little heiid"), or rnilini hrail, 

a «mall ruundetl surface, which, with the groove internal to it, arlioulates with 

le hf^d of the rsdius. It |iH>kK forward, anil is oontlncd to the venlml and a 
jwrt of the inferior sniHace. Abovi' it In fmrit is a slight depression for the edge 
of the he-ad of the mdtiK in <-omplele flexion of the elbow. The ej-tryittit tmiditle 
M on the )<4iine horizontal plane with, but less prominent than, the internal. To 

i* attachitl infcriorly |[w common tendon of the forearm extensor nuistles, the 

tcnuii lateral ligament, an<], moiv dontally and internally, the anconeus muscle. 

' It U DHully ilvM-ribta] u conialninft the inner lip of the bicipitnl gnmv*. 



142 ^^^^ THE BOXES. ^^^^^^^^^H 

III iUi iiiit.iiral piwitioii |1k> litmicruH is t\t'lst<'<l iiiwunl s<i rnii(-)i l)iiit t)i4' iDli-Hmn 
troiKlvl<-, whic'ii is in liiK' uilli l]ir licat) iibitvc, IihiIcs tnon- liiiokwniil tli.'iii imv:iixl. 
The |irin<!i|>iil or liiiifrcNl «xi-.si>f tin- ii|>iii-r anil lowir cxlrciiiilict iiiako an aiij^Ii-of 
loiviioii ol" 'MV' will) i)n<- .iin>lln-r, which rfiiresoiitn the anmiiiit <if twilling of iIh- 
bone. Tlie hiiiiK-nts avcrage-i I-'t iiiohon iiilenglh in tlio male anil 12 inclu-!' in tlw 
lemalc. The coadyleH atone are Mil>ciitaneoii->, and are imiHiriant ha landmark!!. ^J 

Vartetlfi. — The thin plate of buim between tlie olecranon anti i-fii-onoid f'os.'OB'^H 
Jm sonietinies ]jerfomicd, furniiiig ihe ittprali-oc/tlttir J'oramcn. A -nniall hook-like ^^ 
miprncmnltilnf jirutxKi', connected by a fibrous band with x\\v internal condyle aiioiit 
2 mcli(»s Iwlow it, is otfiitiiouallv twinil. It reprL'^wnl*' ii similarlv iihieed Imnv fora- 
men ill niaiiv animals, anA, like it, trun»niil!' lliroii^b the areh the median lierve 
tmd oftoii llie bniehiiil arterv or a larjie lirancli of It. 

Omilfie-'itloH occurs from a primary centre in the shaft uni) •■'ix or seven seeoutl-l 
«ry eoTitres in the extremities. In the tipper extremity eeiurev np|)ear in thel 
luiid. irreiit InlM-ro-iity, and sometitiie>< in llic small tidxi-osity, Hhieh. after fn^^inff 
roplhcr, join l!ic shuft iibniit the Iweiiticth yciir. In the lowi-r extn-mity ei-nlr"-^ 
apjM'ar in the iriKrhlea, citpitellnni, !iti<l ouli-r and inner I'widyle.-', the llin-e lornn-ri 
of which, after coalescing, unite with the >iiiift in the sevenUfiilli ynir. The] 
inner condyle forms ii distinct epipliy^^is which nnit^n Knmeulmt InK-r. 

THE ULNA. 

Tlic uhui ("clbow-bone") (Fips. 1G>*, 170), the inner bone of the fwR-anii, 
i" piindlrl with, but longtr than, the nulin^ by nearly itu' lenfirb of the ole<— 
nuiun. it is inclinetl <lo\vnwanl unil oiitwuiil from the humcnis, so that tho 
great tiibero.->ity and cjipitellum of the hiimeriw and the lower i^nd of the idn» 
are in a stniijiht line, 

Thi' irii'^niar 'i/ijiir extritmJti/ i.« tlie ihiokest [wrt, and presents for artienlation 
with the triH'Mca of the humcrns the i/mit Kiyumiii (" >i(:nia-like") '•nfi/if. This 
liHiks forw.-inl and ripwiird, is euncave fn>ni almve downwnii), and present.^ a ion- 
gilitdinal ridfre wliii-b llts into the gri>ovc of the Iroehlea. At llir middle of the 
oavily i-i a eonxtrieliim (soinelinies h groove) wliieh rppn'.-enls the limit between 
the npiier and hind pstrl funned by ihe oleemnon, and ihe lower and fore jwirt 
formetl by llie e<iriinoid priiivis. 

The thick oli:t-i-auiiii c' elbow-head ") proctiai forms the bighetitmrt of the ulna. . 
On its broad npiter snrfae^ the trieepw is inserted dorHillv, while tlie front of this ^H 
surface projects in a i>e3k which overhangs the great sigmoid cavity, and tits into ^H 
the olecranon fossa of the hnmerus in extension of the elbow. The dorsal surtiiee 
is triangular and suiwulaneous, except for a bursa covering it. The mai^rins of 
the vcnttnl or articular surface give attachment to the internal and posterior liga- 
ments of the elbow. From a tubercle on its inner side pari of the fti-Nor carpi 
ulnaris arises. The romnnlil (" erown-Hkc ") j/rocri'M projects forward from the 
np)K;r em! of the shaft. Its sharp ventral edge, or njirr, is r''»-eiveil into ihe 
eoronoiti fossa of the buniems in Bexion. The veiilnil and inii-rnal edgi> of 
ilif upper or articular surface give attachment to the anterior and inlenial ligji- 
nienls of the elbow, respectivelv. The antero-inferior Mirfacc in rough, and, 
togt'iiier with tlie tubironitit nt ila lower enil, gives insrrtion to the braehialiti. 
The obliijue liiptnient is attaehetl to the outer |Mirl of liu- lidierosity. On the 
inner e>igi' of ibis surface is a tiil)en'le frtmi wiiich |Mir1 of ihe Hexor -nblimis 
digitorum arisi-*, ami from ihc ridge below it part.- of the pronator radii tcn-H 
and flexor Imigus [Mdlicis nri.-«e. On the outer .-lide of the umwr end of tin* 
coronoid pntecs*, and eoiilinuoiM with the great sigmoid cavitv. i« the con- 
cave, oval, mnail itlyniniil r.irilif for articulation with the si*le of tfic head of the 
mdiiis. 

The tiitiji tapers from alKive downwanl. It Is curved inwnni ahovi-, ntilwirtl 
below, as well as ^light]y backward. Triangular in the npjK-r ihn-e-fonrihs, nion* 
rounded below, it presents the following purls : The atUfriar or veritral ijfirtlrr vaoit 



I 



THE VLXA. 



143 



fnjtn tin- iiiiHT innri^n of ihe ci>n>n<)i<l pnn-ess to the front of the styloid pniecHs, 
bdixiiiiijj (■initimii'ii* ill it-i hmer fifth with thf oblii|ue jiroimtor ridgi-. Tlw 
IHiatrriur or tlor/uU honltr itegiwi at tlic a]H'\ of tht- nut)tiitaneouH irianj^k- hchind 
thv iik-VRirion, ami niti? niuuuusly tu thu hack of the biyloid priHU-v, hi-cumiH^ 
low (ti*Liii<;t Ik'Iiiw. Tito eiiei'iuu or ^lIta■^>»»ftf^M border, faintly i:mrk(^^ bt'low, iit 
•harply tiiarkt-i) in th*- middle, and eivew nttachmeiit tu lUt- iiitcros-ii^iiiFi mrm- 
liniiir. It tiifnro»tVH jihove into two lint's whkh [>ate to the tw<i cnd;^ of thi- t^miLll 
eif^udid i-avitv, iiihl enolooe a trianjriilar (i|iticc which, with tl> prominent dorsal 
(>i>nler, cAlh-il tin* mifiinalor ritlpe, gives oniriii to the 8iipinatur inn»-lc. The rcii- 
tral »urfmx giv«t origin in the concave upjicr thne-fourtlw to tW flexor profntMliis 
digitonim, and in iIms lower fourth, below the oblique pronator riiU/e, tu the pro- 
nitior finadrattbi. In the middle tliini is the nuUtoit foramen, dirwtvcl upward. 




n,ci. MiaL. 




nil. c*B*i 

UIH. 



ncx. wiBk. 
oio. 



rmtm. Ttoc* 






Pm.m— TlMbofitaofUicrtRhi ftHMm. Tcntral 
Ttew. iTMtut.} 



fvt. IW,— Ana* of rontmlai ■tUehmnit, vcniNil 
upcrt of till.- Mil] 111 BU'I ulna. 



The intfrnal mrfaxe pivea origin to tlie flexor profimdiis digitoriini in its iipgier 
til roe- fourth*, below which it i.-* siibcHtaneoun. The doruif "iirfnc: is inclined 
"iighlly "ulw-ard. To a triangk on iw upjwr fourth, marked off by an oblioiie 
linv fmni tiw supinator ridge to the dorsal honler, the ancuDeu!> is iu§erted behind 
nmi intertial to the i^upiimlor tinangle, Ilelow tliiK a vertical ridge ^^ejNirates an 
inti'rnal ap«ii, covered by the extensor eariii ulnari^. from an external area, fi-otn 
which ari-i^ in order fmin above ilownwanl the extensor o«sis metaearpi iKiIlieis, 
the extenxir loiigun gxilliciis mid the extensor imliei:t. 

The ImrfT nHrrmily in khiuII. ikhI pri-iciilR ( I) n r»iiiKlc<l /«■»»/ with ii fliiltcnr*), 
wmtlunar artii^ular facH inforiorly, whidi plnvti ii|>iin tho Iriiingiihir fibn>-vur- 
tila^, aud a convex facot ext«rim)ly rer«ivcd into the riignioid oivity of \\w 



144 



THE BOXES. 



rucliu.4; (2) tho ftyliinlw-ul uti/loitt (" jiillur-tiki*") priifrim, wliidi iK-MH-nils from 
the inner ami liai'k iwrl <if llio head. To its extromily is atla^^lici) tin- iiiu-rnul 
lateral ligament, and to the dcjuvssion at ilic outer side ol" its hoM- ilie triniif>tilur 
fibro-<!aPtilage, In the groove In-hind and hctweeii it and iho head glid<.^ the 
tendon of the exteniior carpi nlnaris. 

The subcttiantoun parts arc the triangular hind surface of tlie cdecranon, tlie 
dorsal bonier, the lower fourlll of tlio Inner surface, th« styloid process, and, in 
pronation, tlie outer and fore pnrt of the head, ^iotice tliut the ulna does not 
articulate directly with the cariius. 

Oi««iJi4vilio7i occur* in «irtilaj^ from one prininrj- cenlR' for the >^haft. The 
iipjwr cud of the olecranon, ossified from a scconiittry wntn-, juinji the shaft in 
the sixteenth or Hewntecntli vvur. The lower cxtretnity, cwt^ilying from »n 
earlier formed centre, joins the »hii(l from aboul the t'i(<hli.i'»th to (he twcntidh 
your. 

THE RADIUS, 

The radiiui ("sjwke"), the outer bone <if the forearm, take^ little part in the 
elbow-, but the pnnci]>al iiart in the wrist-joint, articulating with the scaphoid, 
semilunar, and ulna l>elow, the humerus and ulna above. 



I 




poiTtmon 
■onotM 




^ 



ym. 170.— Th« booa of U» rtiihl Ibrcuin. ional 
vicv. tTalul.i 



Pin, in.— Aiviu iif mwoular Hllnphmeiit. dacwl 



The di*c-;*h«]>cil upprr erirrmUif. or lirad, pn'sentiS, ifujR-riorly, n Hliallow aitio- 
ular depression wilh an encirrling rim, which articulate respet:tivcly with the 
capitellum of th« hiimcniit and the groove intonial to it. Owing 1o the ventral 




THE RADII'S. 



Ub 



W\y 



the liittor atKl the nuli 



pftdttioii tif iho capitfluim, rontiu't 
iiitiuinif- in flcsiuii of thf oilx>w. lt« ^mootli, >iliort, viTlk-al niiin;tn le tiwjjor 
iiit«roaltv, where il articiiliiu-i^ wilii the !^iit»ll xi)^mot(l CHvity of Uic iiliui. than 
vxternaliy, wti«iv it i.t i'ml)nii!i.Hl Uy lli<* orliit^tiliir li^mtnit. Below the hi-ad 
U a conxtricltil ntek, wliioti is eni)tinitoiL-< with the Aimft n[>(Hmiio tlic bwipUnl 
hibtrotit^. Tho latter, ■<t{iiati-tl veiilni-inteniallv, has a nmirli ilcirxil iHirttoii 
fnr insertion of ih*? I>iw|*« tendon ami a sniootner ventral jwn (■"verc'd hy u 
hiiT^. 

The diaji is triai^nlar, curved outn-ard and slightly backward, and Ixx-nme^ 
larger below. The iWrrifn/ or interonseowi fewrfer, commencing helow the liiei|>itnl 
lalivnieitA', in prominent in the middle thrpc-lifth^, and divides in lite lower lifih 
into two lines, which pass to tlie two ends of tlic sigmoid cavilr. The interosseous* 
nwmbranc is attached to It. The mttmt or mitfrior and the dorxnl t»- fiosterior 
h'ir-lrrf, ommcncinji also Ht the tnlKTn«ity, pjiss "bli<)wcly downward ami oiitwanl 
«!• the rf-nintl {inttniiir) ntiil rlfrmil (poeicrior) obUqw: linm to the jiinetion of the 
<ip|HT uimI middle ihin);^, utid tlieiice dwwnd (o the front niid hack of the styloid 
jiroi.vxM, becoming Icjw marked lielow. To iJie Ventnil ohliqiie line ihe flexor bu1>- 
liini* digitorum i» attm-hed. Thi.: uri-ji between the two niiliqiie line*, externally, 
give^ insertion to the siiiiiiiiitiir us fur down iis rhe rough inijiR'i'Mon for the 
pronator teres, silnatiil nlxint the niiddli- anil at the nmsl jmintiixtil jutrl of the 
tjienuil lari'iir^. Below this point the exlirniil surfaee is eoven-d by the exten- 
sor tendons. The rmlni/ Kurjhf<- gives origin in its iipjKT twtnthinis lo the flexor 
loQgus polltcis, and its lower fourth gives insertion to the |iroiiator <jimilnitu». 
The RMti-inti foramen, directed upward, is seen above the middle of this siiriaoo. 
The Mortal gurfaw in the middle thini gives origin to tlie extensor ossis metaear|ii 
potlicts above and to the extensor brevis pollicis l>elow. Its lower third is coveret) 
Dv cxtenMHT tendons. 

Tlw latter crtremit^ is broad, thick, and quadrilateral. The large inferior or 
farpal ttuface, oom^ve and triangnlar, is divided by a ridge into an outer tri- 
anpilar surface, which articulates with the scaphoid, and an inner (jiiadri lateral 
Mirfacc, which ariiculatcs with the semilunar. At the lower end of the inner 
eiirfiiet- is the narrow nl^moid carit)/, <;oncavc fnim Ijcfiire backwarti, which articu- 
late* with the head of the ulna. It is at right anglcii to the carpiil surface, and 
tin- «m>t"th margin between tlicm gives altiiehnient to the bsise of tlie triangular 
fibriM-nrlilnge. A tninsverH- ridge at the lower end of the rrulntt mirfarf limits 
ihe att»chni4;iit of the pronator ipiudnitos, and lo it ami the narmw sjhiw below 
it tJM> nntt^rior ligament of the wrift-joint is attached. The wIt or dorim-vjrtrrHnl 
marjaet' is |)rolonge<l downwunl <iiilo the stunt, pyramidal, sulK'Ulaneousirf^v/oiVi jjroe- 
i-jk. The latter is lower than the styloid ]iroee!vs of the ulna, and is an important 
hiwlniark in diugnosticHting fnietures. Tn its tin is altaelied the external lateral 
liirimcnt.attd lo its base the lintehio-riidiali^ nins<'le. Two grwjves, separated by a 
ridgi-, are seen on this snrfiiie ; the ventral one gives passage to the tendons of the 
esteUBor oasis melae^rpi |K41icis and the extensor brevis pollicis; the dorssd and 
inner one, sometimes svibdivtded by a low ridge, glx'es [Hlssage to the tciidous of 
the cxtensorcs carpi radiales longus and brevis, 'file (/ori«/ #rifr;«(v extendi" lower 
than tlw ventral, and of its two grooves the narrow external one for the exlciiifor 
lougoit piillicis is wparatcd from the Iasl-mentione<l groove on the imter suriin'C 
by ■ pmniiwnt mbeuhinoinx tubercle. The inner dorKul groove (nmsniils the 
extensor <'onmiun>s digitoniui and the cxtenwr indicia tendons. 'Itie jwisterior 
annular licument converts these grooves into oanals by its ■Itaehment to the 
dividing ridgt-t, tin- styhml pnH'cxs, and the inner margin. 

The railius \» mmn- deeply phni-fl iliiiii the ulna. In supination the two bones 

arc parallel ; in pronation lh<- r:i<lius crosses the ulna. 

Omiifirtifion priH^eints from one primary eeiiire in ibe shaft, a secoudarj- centre 

in the head, whieh joiiLs the shaA in the seventeenth vear, and a sMxiindarv centre 

in the lower extremity, which appears first, but does not aiikylosc with tlic shaft 

onlil tlw twentieth year. 
U 




146 



THE BONES. 



THE BONES OF THE HAND. 

Tlie nkolcton nf ttic liumi is innii)M>ted of the bonc-s of ilip carpus anil uiotn- 
liikliiiigo, fnrmiiij; ilie i^keleton of the wriwt, the palm, ami tla* 



cnruiii<, «ii(i the iihi 
digiU, nwpeotively. 



THE CARPAL BONES. 




Pio. IW.— The iH-nv- If Ml 

Ofthc ronurm bihiit.<4. iri<] lli< i 

OUpDl boDG*. llonUl IU|»'>:1. <U 






[ the 



The eight carpal bones (Fig*. 172-176) «n* urmnfrcd iii two mvrs of fimr rach. 
The carpus id tmnsvcnwly convt-x ou the (iorrtal surface, and ooneave on die 

imlmar surface. On the [mhiiar sur- 
aee, at the inner and oilt#r cxtrom- 
iticfi of each row, there is a protni- 
uenee giving atiaehment to tlie 
anterior annidar ligament, which 
conipU'Ies a canal for the flexor 
tendons and the median nerve. The 
npljcr burf'aee of the npiwr row is 
convex, arlienhiling with the ts.ia- 
(.•avitv i)f the riidiu;^ and (he Innn- 
gnUirfdiro-i-artilage. Threonvexity 
vxtenil'! i>nlo the (liirsiil more than 
onto th<- imlniarHnrfare. 1 ii the line 
of a Mien hit ion liel\vei-n the two row* 
the eimvexitv of the tm mn^nnin and 
nncifiirm is i-eeeived inin the ("on- 
ca\ ily of the bones of llie flrst row, 
and the ronvexitj* of the 8ca])hoi<l 
is iveeived into tlie slight coneavilv 
of the trapezium and tra])ezoia. 
The lower siirfaM- of the lower i-ow 
i." irregnlarly tranfiven^e and artic- 
ulates with the metaearpus. In 
general the carpal hones are short and irregularly cnhoidal. The dorsaf surfaees, 
usually the larger, and the jKihnar ><nrfacc6, more irregular, are rough for liga- 
mentous attachment?. As a nile, rhe upper and lower, and outer and inner 
surface)- of these bones are articular, to artieidiite with the t>onew above and below 
and on either >ide : hut a lateral >iurfaee <if the terminal bones of wieh row is 
min-arlieulnr. Knumerated fn>ni the radial to the ulnar side, the upjur row oon- 
»i«» of the iwuphoid, seniihinar, cuneiform, and pii^^iforni ; and the lower row of 
the Irapexiinn, tni|K-xoi<l, ns ningnum, and niieifonn. The priiiei|ial inilividtml 
point" of the separate boiii'^ ixn.' a-f fnllowit : 

The Scaphoid. 

The smphoi'l ("boat-like"), the largeiit bone of the upper row, is elongated 
downward and outward. Of the three arcienlar Mirfaci'Si. the upper Is convex 
and triangular, ariieulnling with the mdins; the lower is convex for the tnijx-zium 
externally and the tra|»ezoid intenially ; and the internal is concave helow for the 
OS magnum, flat and cresecntic above for tlie semilunar. The outer end or i^iirfaec 
ic prolonged forward into a strong conical Uthrrvttty, which gives attaehment to 
the iinnitlur ligament. The dor«d surface is a mere groove providing utlKehmont 
for the posterior liguments of the wrist. 

The Semilunar. 

The ■fmiVnwrr I" half-raoon") presents four articular snrfacies, of which the 
upper is convex f'lr ihe radius; the lower is concave for the os magnum, and, 
near its inner margin, for the nneitomi ; the external is ercseentie and narrow for 
the scaphoid ; and the internal is (luadrilatenit and lai^er for the cuneiform. 



147 



The Oimeifonn. 



The cunriform (" w«<lKC-»ha[M-<l ") or fit/ntmiital Aojw in plnced wilh it* hlimtol 
apex tlinN^tctl <low'iiwar<l and inward. Thiii boue also {>rei«ni.4 four ariiviilar 
itoiH», Tliv bajw iirtiviitAt^s witli the waiilimar. TIk- upper siirfacf^ U convex 




Fw. m.->-Th« bone* or Ui« rlgkt hand. pilmoT upcct. (Spattcboll.) 

»ntl i>inuuth externally for the trianyrtitnr librt>«irtilage, rough itiierrtally for Iip>- 
mentit. Tlie lower aurface i.* eonoav^w-onvex for the iiiiciform. On tin- juiltmir 
surtace noar the apex is ii circular faeet for the pif'iforiii b<ti)e. The iiiliTiinl 
Utcral liffariK'iit of the wriijl U atTaclie<l to tlie apex. 




148 



THE BOXES. 



The Pisiform. 

The pm/nrm (" pca-sliaped ") hone is vcrticallj- spheroidal, nrwj has n singli 
oval ariiinilar fucnt uorsally for tlic ciinviform. Tti« rcj<t of llif bi>nc proj«!i!* for 
ward an ono of tlio iiitmiul cniinciici'it fur the aiiU-i'ior nnniilar li^miciK, and 
giv«ti insertion to the flexor ourpi ulnai-is. Tliv <iiit«r .»tde in Hliglitlj' oon«ave. 

(■•••.J 



nrtHMa oMia 

METaCKRFI POLLIC1* 








Horuraoutt 

t'Hl.) 

DIOITSNWa ] / ^"^ 

BlfiCTanhtH 

(■>■■.) 

Fia. t;i.— Arcu nf iiiunrulii aiurliiiicui -jq Iho p«liii*r <iirrar>' <'t thv baiii<* ut iliu livii) Wliam Ih» i 

of orljfin atul iiiuffLiim nrr Ijiith jin^wiiiud. Itauy 4nr lu ilio Hi(ia« vi'tor, JJf^, ■- jD'vrllHii- yLO.UpM.U'— duxoff 
D«ib sirlncurpl mliiliul dlgld. 

The Trapeziam. 

The trapeiium (" tabic "). rhomliio in I'omi, is the most exicnml bono of the 
tower row, and llitn-forc hiw liiil thn-e articular -tiirfacea — a superior, i^liglillv con- 



THE CARPAL BOXES. 



149 



cavp, for ihe iwatilioid ; an inferior, .sndclle-Blinpeil, for the base of the first mela- 
mqul bone ; ami an internal, dividwl by a ridg<? into an upper and larper one for 
l)ie trapej:o)ii and a lower ami shiiiIIlt for the Uise of the liec'oiid metuearpal bone. 
Oil the jialoiar ^iirfave there is a verlioal groove for the pasNige of the flexor carpi 



®3W^ 




■ no 

•HIUNK 



Fm. IMl— Tlie bciiua nf ihe riKhl likiul. docMl upccl. <Atlcr Hpaltcholi.) 

indialiii Uimlon, and external to this a ridge or tuberosifif foroiiDp the wjcund exter- 
na] proiuioenoe for the attachment of the anterior annular liganieiil. 

The Trapezoid. 

TIic trapesoM ("table-like"), the »imall(t.t bone of the lower row, 1ms its 
longest (ItiimeliT from bc-fun; Imckminl. Ita doraal surface is much larger tluin 



150 



THE BOXES. 



the iKilmar ; iu four urticiilur atirfaops are nearly continiitiuK, and prnwnt iw|>e* . 
riorly a. fltnull, concave, Irinnguiar facet for the fu^iphoid ; inferlorlv, n luiigi 






■lkDIIM.1* lOHQUI IIH*J 



CITtNMB 

•nan uinKKra 

«M>-) 



kXTOIHN COMKUttll 
,_ DICITonulll Ana 

hmiKiii iimmi oioifi 




Tia. ITA— Ah'Ui i<f miueiiUt iiiuphtncnt nn tlic ilonul lUTfiuaarilMboiiM nf the haDil. WTieT* lh« mtfm 
>t orislii mill Iii9vn[uii iitg biiili (iiiwitiUil. thvx uro In tlir, uniii oOlar. DIB.— intcrtlon, 

RiidtUo-sliiiiHtl fnret for tlic w^niml nict»i:ur))al bone ; csteriiiilly, u oonvejt laMl 
for the trajH-xiiini ; nnd inu-niiilly, a fnwt for the <kt mngiiuni. 



The Os Ma^am. 

Tlie OS maffJium ("great bf)ne"i, tiio largest carpal bone, U elongaied verti- 
cally. Binil i)cr»pie« tlic oentre of the wrist. It ])res(?iitfl alwve a rounfliMl hfad 
joined by n slightly constrietod neck to a quadrilateral htttlff below. Il articulates 



k. 



THE METACARPAL BOXES. 



161 



above bv its rminded bead wiib lite socket formed by the icaphniil and ^iniltiiuir ; 
below, b^ three faoel.i, of wliicb tbe middle is tbe lar^^est, with the second, tiiinl, 
Slid fourth luetacarpal bone?) ; externally, with the trapezoid bv a small facet 
below that for the ai'spboid ; and internally, by an elooKUted tu(;el, H^imetinKV 
two facets, with the lUK-iform. lie broad dorsul eurface i* larger than the pnlnmr, 
and is prolonged downward and inward. 



The ITnoifonn. 



!The uitd/orm (*' hook -shaped " I is named from a lar^ flattened liook-lik«- |>n>- 
oeaa., oonoaveextemnlly, which projects forward from ite palmar siirfaei- and fnvex 
attachm<-nl a) it* apex lo die anterior unniil:ir ti^ment. Triangnlar in form, it 
articuUtes above by a narn>w facet on its apex with the scmihmar, below by two 
fiueta witli the fourth and fifth mclacarpal boms; externally with the ob mag- 
nani, and internally by a concavo-convex facet inclined upward with the oiinei- 
fortn, leuving but a narrow non-articular r^urface on the inner Eide. 

The carpal l)ones aSord origin by their palmnr MiirfiuH's to muift of the short 
musclcfi of the ihumb and little finger. 

fAwn/ioaftoN occurs for each bone fmm il sinijli- centre, which appi-ur« after 
birth, nio cartilaginous- m frntrolr, i>ttuated tliirsally belwi-en ihv wMtphoid, 
on magnum, and Ir.ipe/^wl in the fo'lus, la occasionally ossified ^jiunitely, but 
U:tually <HMile»(xv with the >>cupliiiid. 

THE METACARPAL BONES. 

The meiacurpu* {" bvyouil the csirun!-. ") i Fips. 173, 1 75) cwnfuiti* five long 
bom'*, which ^iiipjiort the ling»'ri« ami form the skeleton of ihe ]udm, TIk'V 
divergi- somewhat fn>m eiich other in-low, and form the hoUow of the |qilni by 
being i>liglil]y curved longiinditially, and by nrtiimlaling uith the tninsvcn%-ly 
curved carpus. They arc numbcrcil from withont inwanl. The first is the 
broadct and KhortcNt, the Mwond the lungexl, and (he riT>t decreai^ in length from 
(the tJiinl to ihe fil^h. 

Oeaeral Characteristics. — Tin- h/i/ht mil or /joat is im-gnlnrly rohi<iihil, and 
pre»enL« two n')ii-arli<Mi]iir, riitigh siirfinH^s for ligiin ten tons am) inunciitar iiltaeh- 
menb^ a broader ilorsid and a narrower palmar siirlaee ; »nd three nriicnlnr 
iiurfaoc^, an upgier for the (-aq)U.s and an inner nnd an outer for artienliilion and 
ligamentous union with each other. The xh'ijl is triangnlar and slightly i-urved, 
wjth its onicaviiy in front. On the doival surface a ridge starin at the rairgial 
end, and divides into two lines, each of which end?, in a dorsal tubtrctr on ihe side 
of ihe head, the two lines enclosing a triangular, fJaltened surface covered by ll»e 
ext4-nsor tendons. The dorsal siirlace on the sides of the ri'lne gives origin to 
the doroal interossei ninscleB. The two luteml surfaces, fcjMinileu from one another 
by a [nlmar ridge, afford attachment to the palninr interoK«ci nninelc!'. The carpal 
end of the shaft is the moat slender part. The vhal't of the lln<t melueariHil is 
broad and flattened, ita dorsal snrfawr is sni«>th, iind ils piilninr axpeel looks 
inward. The Awe/ presents a roundc<l articular surface for artieidaiion with the 
first phulanx. Thi? articular t^Tirfacc is bniader and extends fiirtlK-!<t on the palmar 
aspect of the hwwl, where it project* into two Intend cornnii, or jialmnr liihrrt^et^ 
M.-)mnite<) bv a groove for the Hcxor tendon:*. The nidei* of iht- bead are flatlened, 
awl markiit by a dcpn^K^^ion for the liiicml ligainent!<. Tbe articular surface uf 
the lasid of (he firnt metacur|Kil bone i« flatter than that of ihi- others, and ittt 
two prominent [lahnar tiilwroloi!! are for the two itesamoid bones in the flexor 
b«'vls {xdliHs lemloiis. 

Special Cbaracteriatics, — Hisifles those almve given, these concern maitily the 

baiwji or uarj^ial exin-mities. That of the_/irrf mftaearpal has a saddle-'hapcd facet 

for tbe trapezium and no lateral facet, but a tubercle externally for the extensor 

.Msif) metaearpi pollicis. Tliat of the «fcoW mefaaiypal luis no external latcm) 




152 



THE BOXES. 



fiicet, and throe superior feoela — a large, concave, central ono for the trat*^in>id, 
anil mari^iiial ones tor the os magnum and trapezium. Dor«ill_v, near the external 
an^lo it Im^ a tubcrck- for the cxtenMor carpi nidiuliii lonfruH. That of the third 
has a promintnit projection, tlie styloid proces*. at the outer and upper an^rlv of 
the clmt-tini, helow which the extensor cjirpi riKliiiliK brcviis is inserted. That of 
the j'ofirth has two fuoet» cxtenwllv, curri'-^iionfliiiK U> two inieninlly <>n the tliiitl, 
and, l)epidcs the muin ftii-rt ("nr tin- nneiCmin iiliove, there is ]i small htt'l for the 
OS iniijrnani on tlie otiter iingU- dorsiiilv. 'I'he haw uf the Jtj'fh hiin no facet inler- 
nally, but a tnbeixwiiy fur titc extensor enrpt nhiaris. Its upper end i» saddle- 
shaped and dinvfiil siijilitly outward. 

Omiififtilhin iif the nn'tacjtrpal Iwines and phabnj^K pi-oceeils fnim one primary 
tuntre iti tb<> Nhan.anil a jierondarv ei-ntn- in ihc- ha--eofthc first nirtacaqtal hone 
iind of I 111' phalanjrcN iirid in the liead of the other metacarpals. The seoondarj- 
citiire joins the shall hv the twentieth year. In the terminal phalanges the 
sliaft centre Ix^gins in the distal end. 

THE FHALANQES. 

Of" the fiiiirteen pimliinges ("ranks") (Fitr^. IT;{, lT5),ea('Ii finper contaiT 
thrfi- aii<l the ibniiib two. Like all long: hones, they have iwo extn-mitlcs and 
shaft. Tile nhttO", semi-cylindrical, arc convex dorsdly, and tlic roiigh nini^ini; 
of the tiat pahnar f>urfaces give atlnchnienl to the tthcath^ of the tiexor tendons. 
The five of the /ics/ rmc arc the longest, and are slightly enr\'ed longitudinally. 
The thicker up[)er end, or haite, has u transversely elongated, concave articular 
facet (f//ciiMV( c«nVv), and the f/iW«/ cnt/, flattened from before backn'ard, has a 
facet prolongeil onto the pnlniar aspect, and lUvldcd into two condyhv hy a 
(fTOove. The four of tin- ii'-nml mir, that of the thiunb licing wanting, are 
smaller, but »imil:ir, except flint the jiroximal articular facet has n f^light ntc<iinn 
ridge and two lateral dcprcis-'iiins to (It the '^mdvlcs of tin- first row. The five 
to-minoi ar lutffiutl [from iintfuh, " a miW") iihnlnni/i-i have proximal cxtrc-miticH 
like thoiM.- of the Mi-onil rt)W. with tlic addition of n guilmar depression for the 
long flexor tendons. The shiill Inners iri ihe Ihittened, expanded, hiirseslMM*- 
Hha|K-<l distal exfn inily, id' which th<- smiHith dorsid surface supjKirtst the nail, 
Itnd the ttiiigh |iNiniar surfiiii? the pulp of the finger. 

Taken togitlnr, the |iluihitigcs <if the middle finger are the longest, and next 
tltosc of tiie ring, index, little Boger, and thumb, in tlie order named. 



THE BONES OF THE LOWER LIMB. 

The l)ony pelvis includes, besides the saeriini anil coccyx, iilreiidy doiwnbcd, 
the two hip-hones which form the pelvk ifiriUt. Hf.sidcs the hip-honcit, the skel- 
eton of the lower limli coniprises the femur in the thigh, the tibia and fibula in 
the leg, and the tarsal, metatarsal, and phalangeal boneit in the tViot. A Itti;gc 
eesamuid bone, the patella, is found at the knee. 



THE HIPBONE. 

The hlji-hnnrfm r^>rir\,itr »» innrnninnlum ("iinnanieil bone") (Figs. 177, 179), 
is irregnl.-tr in tiirni and shii{H-d snniewbat like the hhideiif a ftcrew-prii[M.-]ler. It 
is narmwcd in the iniddh-, where the •iretnlmlnm, nr socket fin- tlie feniiir, is seen 
extcnmlly, and expiinded aliove and l«dow. The hirg*- n|i[M-r imriion turnis the 
Jiiljie pctriM (" basin "), a part of the abdonitnal wall ; the lower jiorlion, ]H-rtoiiiit'd 
hy the large IlitiroUl ('"shield-like") or v/jfanito/- (".■•ti>niK-r")/«r((W/«i, form-< the 
lateral and front parts of the true pehU, and curves inwArd tu meet its fcUnw, 
The hip-bone trau»miu the weight of the bmly to tlie femur. The three parts. 



THE UIP-BOyE. 



153 



iiinm, uehinm, and on puhit, i>e|iarate in early lif<-, ankvlnsetl in the adult at the 
im-tubuUim, whore they meet, are conveniently n-toenizii;l a.* dintinct in the deserii)- 
tiiin of the heme. In following; the de-jcription liold the jioetorior juirt of tlH) 
ni>teh in the acetabulum dowiiwani, in t)»e natural pwitiun uf tlic buuc, 



The lUtun. 

Th« Uium ("twisted") in the lai^i>, upiter e3cpanck<l portion, whose lower limit 
fornii? the upper two-fifths of the ai?«tnhulum, an<l wht»«e uiumt lx>rder, the erent, 
i>rf«tits tlirte lipa for attachment oi the flat muscles of the abdomen. The crest 
lit 8inuo<iH,/-Khape<l, irregularly thickened, and suliculaneous. 

To the outer lip are attached the tensor vagina- fi-nioripi in front, the obliqniis 
cxiemiis iu the ventral half, the latiHsimus in the dorsal half, and the (gluteal 
portion uf Iho fascia lata la the entire length ; to the middle ridge, llie obliquus 



roue K IS K •urC 

aio* ■*>!■( 










Pro. 17T.— The H((h( lilp^bniiri, MitiT luraii-r. iTwiliit.) 



intemui- in the vcntnd two-thinN ; to the inm-r lip, Ihc tnin--'Ve>snli« in the ven- 
tral ihrec-fmirth^, the r[uaftrutitH hiinboruni and erector npinw behind, and the 
iliac fascia in llie enlin? Icri^h. 

The crcHt ends in front in the proniiiirnl nnterior auperior apinr, to which the 
inguinal (Poujiart'^] lii^mcul, ihi^ l<-tiMir VH^in» fenioris, and the SHrliiHus am 
atiiK-hi-fl. The hitter inii.^cle extciuU unto the notch l»eliiw, which imn.-<iuii.-< lh« 
external ontaneon^ nerve, and st-panites the sniierior fi-om the niittritir iiifn-hr 
»)iiiie. From the latter, niliwted above the aci^iahuluin. the Hiraight tendon of \\w 
rei-tus femoriA and the i I ii>- femoral Itand of the hip-Joint take origin. Beliiw thin 
apine and between it and the ilio-jwctinenl eminence, where the ilinm and os pubis 
meet, in seen the inferior ifi'ir iinlc/i. This is i^itiialcd in fnmt of. :uid above, the 
acetabulum, ami ■» tmversctl by the itio-p^mis nmbclc. 

The crwit ends beliitid in the pimtrrior «uprrior ephir, which affonlji ligimicntous 



144 



THE BONES. 



nnJiu^ : (2t the OTp-lindriojil utiitoul ("pillar-like") pi-DOww, which dcscendg from 
tliL- iniitr iitii) hiK-k {uiri nl' uxy Ik'jkI. To its oxtn-inily is iillitchol tltv iiitvrniil 
latcrtil lig^iiiii'iil, ami to tlio licjit-i-nsion at iho niitirr Me of Ux \r,iM' tlii> I i-iHngiiliir 
fihn)-('.irtilai;i'. In thi- gn>i)ve lii'hiiid ami l)etwi>en it anil iJitt head |rli<lv» lii« 
U-niiciii III' lii(' fxteiicor carpi iilnarifi. 

'i'lic sii/irutanetttM partu aiv the triangular hind surface of the olecranon, ihe 
diirxiil horder, the lower fotuth of the iniipr eurfuco, the styloid proneba, and, in 
Iirniiiitioi), iW- outer and fore part of the head. Notice that the ulna does not 
arlicubu- directly with the cjirims. 

f hKificatioii oecnrs in earlila];e from one primary centre for the shaft. The 
iipiw-r end of the oleeninon. oi-witied from a Beeoiidary centre, Joini- the i-hiift in 
the <4ixteenth or seventeenth year. The lower extremity, ossifying from an 
earlier formed centre, joinH the shaft from »l*oiit the ei^ht«enlh to the twentieth 
year, 

THE EADTOS. 

The rii'lhiM ("^[K)k<-"), the oiit«'r hone of the forearm, takes little jairt in ihe 
elbow-, hnt the i)nn(d|uil part in the wriNt-joint, artienlating with tlie scaphoid, 
semilunar, and tilna hdow, (he hiimenis and ulna above. 




C*ll»l 
VUMBIB 






ITVIOIO 



rio. ITU— Tht liana* at tbr r1|[hl ftiNarm. ilntMl 




■ON. TtHCa 



Fin. ni— .vn>»i' ('f nimcnlat aiurhmcnt. tiMMl 
Mpcvt III ruillw aiiil itlnii. 



The ilii^e-whaped upper wfrfmiV/y. or hfaJ, prewnt*. s«])criorly, a (^hallow artitv 
ular depression with an encircling nm, which articulate rev pec lively with the 
CHpitelium of the hiimems and the groove inti-rnal to it. Uwiii|r to tb« v«nlral 



TUE JiAJflUS. 



145 



I 



■m itioD of the capitclluin, contact hetvrecn the latf«r and the radiin U most 

Hniniutc in flexion of itiv vlbow. Its smooth, -iliort, vcriieal niaiyin \^ (l<^('{H-r 

inleriiullv, whi-n- it urticulalos with th« !i:inail ^igniDJd cavity of the nloa, llinii 

(■xu-rnnlly, wlicn* it i» •.■iiibtsvcd by the orbiciihir li^mont. Below the hcjul 

i^ a non^tri*' !■.-() ntrk, which i» ountiiiiioiii!' wiUi the »hat't opposito the liieijiilnl 

tluhenuiilt/. Till* latter, siUmtdl vi-nlrD-intcnmHy, Iw a n>ti(,'h dorsal nurtjitn 

• liir iib>iTtioii uf iht liiw'iw U^ikIoii iind il wiujihImt ventral jKirt covered hv a 

liiirMa. 

The Kfi^ijt is triang'nlar, cur^'i-d outward and slightly bacJtwanI, and becomes 

iJs^lpr beh»w. The in/emai or iiila-iuou-iin>i /torilfr,K>mmvnr:ine helow the hicijtital 

■ tuheruMty, in prominent in the middle thn'O-fiftht, and dividoM in i)k- lower fiOh 

into two lines, which pass to the two entbt of the signioid <'avily. The intLTO!>M-o(i« 

L membrane is attached to it. The ttiifinl or anirrior and the <Uinnil ur p'Htltrlryr 

} bor-lert, commencing also at the tiiberotiity, pawi obliquely downward and milwanl 

a* the rfNtrat (_anleriori and dorttat (^ftonterior) oblujUf Hue* to ihe jiincliim of the 

upjier and middle thirtU, and thence descend to the front and back of the .'•tyloid 

firoccis, tjeciming less marked below. To the vcntnil oblique line the flexor suli- 
imi* digilurum is attached. The area between the two oblique linci*, externallv, 
l^voi insertion to the siipiiintor iis f:ir down as the rough iniprc^Hon for ifie 
pronator tervs, »ittiatcd iilioiit the middle and at the nio«l prominent part of the 
rjtrriiii/ i-urfiuv. Below this iwinl the cxlenial isnrfaee i^ covcreil by the extcn- 
»>r li'ntloni*. Th<' rrnlral Kitrt'iier gives origin in it" nppiT Iwo-thirds to the flexor 
longns jMillicin, and its lower fonrtli give.* insertion to the pronator onadnitns. 
The nutritnl /oramm, diriHtttil upward, i» seen above the nii<ldle of this surfiiee. 
The iliirtutl mrf'ic^. in the middli' third gives origin to the exrcnsurtis^is melacarpi 

Kllicjs above and to the extensor hrevis ixillicis bi-Iow. Its h>wi-r ihinl ii* covi-rcil 
extensor tendons. 

The Irneer fjiremity is broad, thick, and quadrilateral. The large inferior or 
mrpit/ tur/iUTf, eoiH'ave and inangular, is divided by a ridgi- into an outer tri- 
Mignlar surfaoi-, which urticniati-s with the st'aplioid, and an inner qnadrllatenil 
Hurfncc, whieh articulates with the .semilunar. .\t the hiwer end of the inner 
surface Ls the narrow xlijmoid eaviti/, wnicave from befon' baekwanrl, which arlicn- 
laiai with the head of the ulna. It is at right angles to the carpal surface, and 
tlie smooth mai^in between them gives atlaehmenl to tlio base of the triangular 
6bro-cariilage. A transverse ri<lge at the lower end of the vrulr'ii Kiir/arf limits 
the attachment of the pnmator quadratus. and to it and the nsirrow space below 
it the anterior ligsment of the wrist-joint is attached. Thv oiiI'T t\r ifnrH'i-rxirriKil 
tnrjarf is prolonged downwuni onto tlic stout. pyrnn]i<la], snlx-ulsi neons f/'//«iV/«oo- 
'-w. The hitter is lower than the styloid pnjcess of tlie ulna, and is an imporlnnt 
laixhnnrk in diagno*li(-aling fnietures. To its (in is utlaehiil (lie external liitenil 
lt;f inienl. and to itn Ut-'c ihe braehio-nnlialis niu.'>i'li-. Two gttHive", M'pantlt-d bv ft 
ridgt', iin- sveii on this unrface ; tbi" ventnd mif gives pH.->3gt' to the tendons of the 
exieniior nssis meUtcjtrpi [Hillicis iiiul the extensor bn^vis jtolliets ; the dorsal and 
inner one, sometimes siilxlivided by u low ridge, gives jtassage to the tendons of 
the extensores carpi radinles longiis and hn-vis. '1 he dorxai ivrfaee extends lower 
than the ventral, and of its two grooves the narrow external one for the extensor 
longus (tollicis is separated from the last-mentioned groove on the outer surface 
by a piMminent subcutaneous tubercle. The inner d()rsal groove transmits the 
extensor twmimunis digitornm and the extensor indicis tendons. The ptwterior 
annular ligament converts these grooves into canals by itii attachment lo the 
dividing ridges, the styloid process, and the inner margin. 

Tile nidius is more deeply placed than the ulna. In supination (h<> two bones 
ai? parallel ; in pronation the nulius crosses the ulna. 

Otnific'ili'm prtK-oetis from one primani' cenire in the shaft, a seeouihiri' centre 
in the Ikw!, which joins (he sb;ifl in tin; »event<H'iilh vt-ar, nnil a sccondarv centre 
in the tower extremity, which appcunt flrst, hut doei not aukylose with the shaft 
until tlie twentieth year. 

10 





146 



THE BONES. 




i 



THE BONES OP THE HAND. 

The skeleton nf (lie liand iv ci>ni|iu>«.'<l nf ihi- Ijoin-s of the rarpiis and uiPla- 
curmis, iiiid the l>ll»]llIlgc^^, IVirmiiif? the skeleton of llie wri(*t, the palm, and the 
digits, R!»pvctiveiv. 

THE OAKPAL BONES. 

The eight carpal bonet* (Figs. l"2-l7(f) arc arranf!*-!! in two mws wf four each. 
The cai-puD is transversely convex ou the doixil fiirfmr. iiml (•micave on lite 

ptilinnr Aiirfiiri'. On tlie {•iilmni' i>iir- 
tikeCint tilt- inner and oiit«-r r-xrn-ni- 
ilies of eji<-li row, llii-rt^ i:> a ftixinil- 
neiK^ giving ntlaehnient to the 
anterior annular li^.iinient, uhich 
completes a eanai for the flexor 
lenfloiis and the nitHlian nerve. The 
tipiwr feurfaee of the npjM-r row \f, 
convex, art iciil.1 ling with the («n- 
cavily of the nidiusii and the trian- 
gular filiro-eartilage. The convexity 
«xtrmlK onto the dorwil more than 
onto tile mlniurr^nrfitce. In the line 
of urtietilatioii bi-tween t lie 1 wo rows 
the convexity nf tin- o* magnum mid 
niK'irorm \» rv<-v\\i.-*\ into llie eon- 
eiivity iif liie lionew of tin- first row. 
iiiid ihe (-onvexity of the M-jiphoid 
is n-eeived into the .-.liglil eomavilv 
of ihe trajiiifium and tnipi-Jtuid. 
Till- lowiT ,-iirfiiei- of llii- lower row 
is iiregtilarly Iraii.-iverse and artie- 
ulare." with tlie ntetaeari)U.«. In 
general the earpal hone.* are slmrl. and irn-gnlarly euboidnl. 'I'he doivaf ^urf«eei«, 
niiually ihe largt-r, and the |«ilmiir snrfaees, more irregnlar, are rough for liga- 
mentous attaeliiiients. A.-* a rule, the ujiper and lower, and outer and inner 
siirtares of thexe hones are articular, to articulate with the bones aliove and below 
and on either f iite : hut a lateral snrface of thi' terminal hones of each row is 
non-:irlictiIar. Knwmeniled fmm the i^dial to the ulnar side, the upper row con- 
sists of the si-aphoid, semilunar, cuneiform, and pisiform ; and the lower row of 
the tnipeziuin. trapezoid, os magnum, and uneilorm. The principal individual 
pointt' of the separate bone* are as follow!; : 

The Scaphoid. 

The m-aphiihl ("boat-like"), the larp'nt Wme of the upper row, i» elongaterl 
downwnii) and oiitxvnnl. f)f the tliri-e nrtieular Mirfaeew, the upper is eoiivcx 
and iriiiiignlar, arlieulaling with tlie radius; the lower is convex for the trapeiduni 
externally and the ti«|M-xiiid internally ; and the internal i.a concave below for the 
OS niagmmi, flat and creseenlic above for ihc semilunar. The outer end or surface 
IS pmlunged forward into a strong conical tiiberonttt, which gives attachment to 
the annular liganii?nl. The dorsal surface is a mere groove providing attucliment 
for the (wsterior ligumeuts of the wrist. 

The Semilunar. 

The niTOii^MHfir ("Imlf-moon") pre-Hents four artieular surface*, of which the 
upper is convex for the nidius ; the lower is concave for the os maguuni, and, 
near its inner mai^in, for the uncifonn ; the external i.* creseentie and narrow for 
Ihe scaphoid ; and tlie internal is ^iiadrilaler.d and larger for the cuneiform. 



Fi'i. IR,— ThclK'noi ct liie rlirlil oaipiia. [he dim I *ii<lii 
Of llii' f-irvumi ti-hiin, Aixl U»' iinnliiiiil tii-li of tlic mcto- 

ClUIMl bllTIU, <1lIT>*l HH|IWl. iTi^lulO 



n 



THE CARPAL BOXES. 



X47 



The Coneiform. 

The cvn^form {'* wedg^ttliapcd ") or pyrttmidal bonr u plnccd witli its blunted 
a{M!X directed ilowDwunl iiml inwiini. Tlii:* 1k>i>c iiUu prc»cn1f Intir artiviiliir 
facets. The biuie urttcuUtt^^ witli thu twriiiliiuiir. The u)>pcr «urfitgv \* vuuvex 




FN.in.— Tbe bond of Iberlfflil liani). pslioar uprrl. (Rpaltrhob.} 



and .iniooth cxtoniiilly for the trinii(iiilar fibni-rHPlilnp.', rough iiilrrnally for lip- 
tnent». The lower riiirtntiv i* fuiraivii-itiiivex fur ihi- luiciflirm. On tlic iiiihniir 
Aartiiee near the a]>ex is ii cin-iititr (iiecl fur thi' pUilorni Ixnu.*. The intemul 
~Btenil li^tuent of tti« wrist is utiached to the »pex. 



146 



THE BOXES. 




THE BONES OF THE HAND. 

Tlip skeleton of the hand is comjHisfd uf ihf bones of the carpiw nntl inr 
cartmH, aD<l tlio nhaUmges, formiiif^ (he •'kelelon of the wn»t, tlic pultii, mid (lie 
digilif, n-spcettvcly. 

THE CARPAL BONES. 

The t-ighi carpal Imjiics (Kig^*. 17i-17R) are arranged in two rows of fuiir each. 
Tlie e.-tr|)iut is tran!*versely eoiivcx on tlie <iorsai wiirfnoe, and eoneave on ilie 

pultnar 6urfae*. On the |)almar sur- 
faee^at the inner ami outer extreiu- 
ities of eiudi row, there is » prunii- 
nenec giving ultaehnient to tlie 
anterior anntihir ligimient, which 
Coni[>leli'» II ramd for the flexor 
ti-nihmi^ ami the tneiiiiin ner\e, Tlte 
ii]t[KT enrfacf of the npiwr row i*. 
eoiiveX, arlirnhitinK with the con- 
^^^ cavity of tin* nuliiiN find the Irian- 

jjy\ i^jjp i^^B^fc ^,^fe^ guhirlihrO'i'iinUu^'e. Thi-entivixity 

^tm^^Lj' ^N,^^^V extendi onln tlu' ilomiil nion- tlian 

^*^ *^ C—l^^^^liK*. onto the irahiiarnnH'iice. luthi-line 

of artieulalion between t!ie two mwK 
the eonvexity of the iw magnum and 
nnciform is received into ibe «ou- 
ejivity of the bone-; of tlie first row, 
!ind the convexity of the i^eaphoid 
is received into the !<light eoncjiviiv 
of the tnipezinni an*I tni)H-/otd. 
The h)wer Mirfiiee of tlie htwer r».i«' 
ii« irre^riilarly I mnfiverie and artic- 
ulati-s with till' inelaeiirpiiH. In 
general the carjKil bones are short and irrepnlarly eiihoidal. The diiDtnt siirfaoo*, 
usually ihe larij^er, and the juilinar T-nrfairs, nmri- irrejitiliir, arc roiigli for lipi- 
mentotia attach men ta. As a rule, the iipiiir and hiwer, and outer and inner 
surfaces of the«e bones are articular, to articiilute with the hones aliove and lielow 
nnd on either !ii<le ; but a Ititeral hurfaee of llic terminal bones of each row is 
non-artieuhir. Enumenitcd from llie radial to the ulnar side, the nmier mw eon- 
siml* of the scaphoid, eemilnnar, cuneiform, nnd nisiforni ; and the lower mw of 
llii- ini|>i'ziuTTi, tnipew>id. <w magnum, anil uncHorm, The principal individual 
piHul.N of llie sepanito hones lire as f'lllowe : 

The Scaphoid. 

The geaphoiil ("boat-like"), ihc hirgesl bone of the upper row, !» ehingnted 
downward an<l onlward. Of thr ilire*> artieiilar .'<urfao^-^. ihe npjx-r U e<«ivex 
ami triaujtular, articulating with the radius; the lower is convex for the trajicKitim 
externally ami the trai>ezi>id internally ; and the internal is concave below for the 
o« magnum. Hat and cresceii tie above for the semilnnar. The outer end or surface 
1^ pn>l<iiigiid f.invard into a stmng conical fuhfrtnlli/, which gives attachment to 
the anrndar ligament. The dorsal surface IB a mere groove providing attachment 
(itr the ixji^terior lignmentii of the wrist. 

Th6 Semiltuiar. 

The temilunar ("half-moon") prt-sents four articular unrfane-s of which the 
up|»cr is convex for tiie radius ; the hiwer is concave for the os magnum, and, 
near it« inner margin, for the unciform ; the external is creseenlic and narrow for 
the scaphoid ; and the internal i(= quadrilateral and larger for the ctinciforra. 



Fill, 173.— Thcbon« or the rlKhtcarpiii.thc aittnl tttAt 
of llii^ forvarin tnnm. iiid Uir iiniilmul twu of (lie met*' 
oupal buno. ilonal uaiHU^t. |Tvtliil,| 



TUB CARPAL BONKS. 



149 



cave, for the scaphoid ; an inrerior, Baddle-iiha)M-<], t'or tlio has« nf tlie fimt invU- 
mrpal bone ; ana an internal, ilivitM by a rld)^ into ait upper and laiyer one f(»- 
thv rnipexoid aud a loner and sniallur for the buKP of the second niflacaqial iKiiie. 
On the jnlniar surfaw tlicn; ii^u vertical groove for the passage of the flexor carpi 







nsL lis.— Tlie boae* of the liiiht huid. donil mpccI. (After StxtlM^it*-! 



radiatie tendon, and external to tins a ridgc or hiieroeifi/ forming the second I'XttT- 
nal pruniineuoe for the attachment of the anterior annular ligament. 

The Trapezoid. 

The irapfMiii (" tablo-like "), the (tniiillcrtl bone of the lower row, baa its 
loiig«nl dianwter from bi-fure backward. Its doriial surface is much larger than 



148 



THE noyEs. 



The Pisifonu. 

The pwiform (" pea-shnped ") l>one is xcrtically spheroidal, and has a sin^ 
oval artkiilar facet aoreally for the riiDoiform. The rwl of the linni; prtiji-cts for- 
ward an cmi- of tlic intornal ciuiiKiici-s for the ank-rior anniiliir liirnitiiiit, mihI 
gives iiisertiuii tu the tiexor tarpi ulnaris. Tlie outer sidv i« .-.Hghily toncave. ^ 

(■N»J 



CtTtHMN OMIB 

■ Elacan*! rOkllCI* 





PHOtUNaUt 

OlaiTOKUM 

(IN*.) 

"■" SIBITOnUH 1 / ^^ 

rKMA 

OiaiTOHUM 

Fio. 171.— Amu of muHiiUr aitucliiocut on Iht |MiIm«r «urfnpi' uflhrboncior Ihc lianJ Kh«» th«i..„ 
atorlKln nii'l luicrUuii niv IxiUi iimviiUd. tlu'j' itrr. lu llt« laiiie vul»t. IMS. InHTlimi. fl-O.M.M.lV-Raiia 
ool* nttucuriii niiinial iltflli. 

The Trapezium. 

The tmjtrziwn {" iahli^"). rhombic in form. i» thi> nicwt external hono of tJi«1 
towi<r row, and then-fort! ha.-> hut thrt-e uriitrular i>iirfiti:es — a .'•ugierior, .^lightly cod- 



' ^^^P THE MKTACABPAL BOXES. Ifil 

abovf br it« muixlvd h<>ud with l\n- mk-UvI IbrnwHl hy tti« iwnpltotil and Mmiltiiuir ; 
' below, by Uiret* lac>cU, nfwliicli thn niiddlf in th« I»rgcftt, witli ibv Kii'uiid, third, 
'and fourth nu'tnctrpiit Ih>i)c.-<; externally, with the tra|>ezoid hv a »niull jaoetj 

belnw that for the !u-a|i)iiiHl ; and inlenially, hy an eh>nffai<Hl faoi-i, MtnivlimW'^ 

twii faoetii, with thi^ umilunu. Ilx linud dorna) miHace is larger than the pulmar, 

and is |H«ilui^eil dowaward and inward. 

I The nneifono. 

V The uneft'briR ("hootc-^haped"! is naiueil from a large ilntietif^l hotik-like pro- 
Mii^ooDCttvecxtt^mally, whicn prujocti forward from ii^ palmar surface and tpvn ' 

•tiachmi-nt nl iti itjxtx lo tlie anterior annuhir ligament. Triangular in form, it 
' articuhitcs iilnnv by a narrow tacet on its amx with iIk' »eniilunar, Ih-Iuw by two 

faects with the fourth and fifth metacarpal bones; externally with the iw mag- 

nnni, and internally by a concavo-convex facet inclined tipwanl with (he cunui- 

form, leaving but a narrow non-articular surface on the inner side. 

The earpa! bones aSonl oriKin by their palmar i-iirf&eeB to most of the short 

muscles of the thumb and little finjp^^r. 

Onnification occurs for each bone fn)m u single ccntrv. vlilcli apjK-ars after 

birth. The cartiliiijinoiis on caxtrulf, »ituat<tl durMilly iwlwcen the scaphoid, 
I OS luuinium, ami Irajxv.oid in the fcptus, w 04.TU»ioiially mwilied liepurately, but 

usually c-oale^M'^ with tht^ KCJtplioid, , 

THE METACARPAL BONES. | 

The wirfaftrrp'w (" beyond the caruus "M^'Pn 17^, 175) conliiins 6ve long 
bones, which siipfKirt the finRcrs and form the skeleton of the palm. They 
diverijv somewhat from e.ich other below, and form the hollow of the j«dm by 
being slightly cun'cd longitudinally, and by articulating with ihc tmnsversely 
curved carpus. They are numbered from without inwartl. The first is the 
brr>adc"t and shortest, the second the longest, and ihc rest decrease in length from 
the thirx) to the fifth. 

Qfineral Characteristics. — The tipppr rn<l or htiKr is irn-pulnrly cuboidal, and 
presents two non-arlicular, rough surfaces for ligiiui(-iitou>f and niu>^cular iiitach- 
incnts, A bnxtder dorsal and a narrower palmar i^iiHii<r ; and three urtlenlar 
Knrfiicte», an np^H-r for the eari>ns. and an inner and an oiUer lor articulution atid 
ligunientons union with eiwh other. The vlfijl i» rriangnlar and olighily curved, 
with its eoniiivity in front. On the dorsal .snrfiit^' a ridg<- starts a I ihc carpal 
end, and dividi-.* into two liniw, (oich of which ends in a di-nal tulnrcin on tin- side 
i>f the head, the two linc-H enclosing a triangular, flattened surface eoven-d by the 
i:xti-nMir teinlon.*. The doretal riurfaoc on the sides of the ridee gives origin to 
the dorsal inlenMsei muscles. The two hiteml siiriaces, separatee! fn:>oi one aiHither 
by a palmar ridge, afford attachment to the palmar intorossei muscles. The enriuil 
end of the shuil is the most slender j>art. The shaft of the first metacariial is 

C broad and flallened, its dorsal snrtaee is smooth, and its ptilmar iispect looks 
inward. The AtYi'/ presents a ronndtnl articular surface for artieuhittou with the 
first phaliinx. This articular surface is broader and extends furthest on ihc imlmar 
aspect of the hew], where it projects into two lateral coruua, or pttltiirtr fubrrcif», 
wpanitcd bv u gnxtve for the flexor tendons. The sides of the head arc flatlene<l, 
and nutrk*ii by u depression f'>r the lateral ligfiincnts. The nrtieiilnr surfiice of 
lh<' h.^id of the fir»t metaairpul bone is flatter tluui that of the others, nnd its 
two proiiiiuenl |Hilniar tubercle* are for th« two s<Minioid Iioncs in the H«xor 
brevi.-< [Millici.i tendons. 

Special Oharacteristlca. — Reside:" those aliove given, ihese (Hincern mainly the 

hfue* nr (tirjial extrcmiiie.*. That of ihc^rj«( mfimyirjiirl lia.t a saddle-sha|K-d facet 

for tliv Irapezium and no lateral facet, but a tubercle externally for the extensor 

i» melacarpi pollicis. That of the xfcoiid metacarpal has no external lateral 



^pwt» mela 



152 



THE BOXES. 



facet, and three Buperior facets — a large, coneave, ct-ntnil one fi»r the trapezoid, 
and mart^infil vtwvs tor the ns magniim and tru{K-ziiim. Dormlly. near th<- external 
an^le it liiui n tniwrcle for the extenwir car])! nidinliis Iniigiii'. That of the ihinl 
liiiK a |>nmiiririit pnijcHion, tht' islvloid ])nM'e!'». at the outer din) iippfT a n^le of 
the iliirsuni, lii'liiw which llir exteiiMir carpi nidiiili,-. hn-viii is inserted. Ilia t of 
the /'iii/Y/i has l\vi> fae<-t.-< exteriiatly, eorn-.-poniiin); td two internally on the Ihirtl, 
mill, licsifli-s (he miiiii fiii-ci for the iinciibrni above, thiTi' U n .-mall laeel f»r ibe 
OS iiiapiiun nil the outer angle dorsally. The hane of the pjth ha« mi faeet iitler- 
nally, but n tuberofiity for the extensor carjH idnaris. Its upper end is saddle- 
xhaped an<i direeted slightly outward. 

Oixifit^dlioji (if ihe nieTaearpal bone^ and phalaiiijeB pi-neeeda from one primary 
peotre in the shaft, and a seeondarveentre in the b:i-* of the first nietaear^tal bone 
and of the phalan?<'s and in the head of tlio other nietaearpals. The seoondary 
centre joins the shaA by tlie luentietli year, In the terminal pimlanges the 
shall eentre begins in the dii^tal end. 

THE PHALANGES. 

Of the fourteen phalanges ("ranks"i (Figs, JTS. 175), eaeh finger eontain 
three and the thumb two. Like all long bonc^, they have two estretnitics and ii 
shaft. Tile thiifin, semi-eylinilmiil, are convex florMilly. ami llie rough margim' 
of the flat palmar ewrfuees give attaelinicnl l« the slu-iiths ol" the flexor tendontk 
The five of the fird roir iirc tJic longest, and are slightly curved longitudinally. 
Tlic thieker upfK-r end, or Afwc, liiis a I rsinnverwiy elongated, e<>ncav(; articular 
faeet ( ;//i'ii"iil nirily), and the iluihil fiiil, lliitlened from before baekwunf, has u 
facet prolongiil onto the [Hilniiir a.^pivt, an<l divided into two eundvh'K bv it 
groove. Tile four of the xi-Mmti rfnr, that of ihi; lliiimb being wauling, arc 
umiiller, but xinular, exeept that the pmxinial arliiuiiir tiieet lia.? a sliglil mediiui 
ridge and two lateral depr(-*iionH to til tiie condvleH of ihp first r.iw. Tlit- live 
trrmiiinl tyr itui/iiiillfrom utujuix, '"a n.-iil") jihnlnnfrrK have pnixitnal extremities 
like Ihtwe of the seeoml row, with tlic addition of a pnlniar depri-.»sioii for llie 
long flexor tendons. The hhaft tiiwi-s to the flalleni'd. exiuinde^l, hoiNe.-hoo 
shaited distal e.vtivmity, of whieh llie smooth dornal surface HUpjiorts the nail, 
and Ihe rough palmar furfaet' the Jtulp of the finger. 

Taken together, the phalanges of the middle finger are the longest, and next 
those of the ring, index, little finger, iind thumb, in the order named. 



THE BONES OF THE LOWER LIMB. 

The bonv jjelvis iiicltides, Wsidcs the sacrnni and coc^eyx, already deM^tibed, 
(be two hip-boneii which form the prlvic girdle. Itesides the hi(>-lii>nes, the skel- 
eton of the lower limli comprises the femur in the thigh, ihe tibia and fUinla in 
the leg, and Ihe liirsiil, nietat;u'i<nl, and phalangeal boiiei^ in the foot. A lnrg<> 
»esamui<l )>unc, the pnlellu, is found lU the knei-. 



THE HIP-BONE. 

The hip-hone (m eojw), or oa hitiomiiuiluM y unnamed bone") (Figs. 177, 179), 
IS irregular in form and slia|Ktl somewhat like the blade of a serew-|iro|H'IIer. it 
is narrowed in the middle, where the dceiahuhim, or socket for the teinnr, is well 
externally, and ex|>iinded above and below. The laige npjH'r portion forms tlie 
/nt«r prfriit (" basin "I, a psirl of the abdominal wall ; the lower iiorlion, iK-rlbrated 
by the large Ihyrohl (" slneld-like ") or ofttuinior (" slop|>er ")foranieH, forms the 
InlentI and front [larls of the (rne pr/vi», and curves luward to meet its fellow. 
The hip-bone ininsmitx the weight of the body to the fetnur. The three parts. 



THE HJP-JiOyE. 



163 



Uiam, urAtum, and m pubis, aeparate in early litV, aitkylo^ed in the acliilt at (lie 

I aoctttbnluni, whcro tWy meet, are cunveniently rceognized oh dii^tinct in iIh- <U>««riii« 

lion of tlif bijne. In i'ullowiiifr the description liolil the iKwIi-rinr jiari of the 

n<KcIi ill tJiL- ucvliihulum iluwiiwani, iii thv imtunil |w«itiuu of thv Imiu:. 



The Dinm. 

The Uivn ("twisted") is the targe, upner expanded portion, wliose lower limit 
fomii^ the upper two-fifths of the aeeiahiilnm, and whose up]KT IxmUrr, the rrwf, 
priTjifnlj* lhn-<.' lips for uttaehnieat of iIr- flat muselcs of the nlKlomt-ii. The crvTit 
M »intiii(Lri,/-Kliiipr<i, irregniarly thiekeiieil, and snbciita neons. 

To llie outer Up are uttiiehcd the tensor vo^iiiie iVmoris in fiwnl, the obli(|iing 
exientm in tlie ventral half, the hitiseimus in the dorsal half, and the elolc&l 
jiortion of the tiiseiu lata in the entire length ; to tlic middle ridge, the obliqiius 



•* V.', 



■ion ■nni 



vosnntan in- 
rtrnxen anHt 




■loa ariHi 



'HTiaiOH (■•• 

ft* ion aMiic 



■nut OP, 

■■CHIU 
ROTCH 



Tio. 171.— Tbc r!)[ht Itlp-bonc. oucrrnirlhcc. (Tt«tut.} 



Tntemu" in the votilral Iwo-iliinis ; to the inner lip, the trannver«ali.'* in the veti- 
Ir.il ttirce-l'iiiinhs, the ipi:idnitii» linnlumini ami oreeti>r spiiue lieliind, and the 
iliue faxMU in the entire lenji^th. 

The ere!*t emla in front in the pmininent nnlerior superior tpive, to wliieh the 
inguinal (Powpari's) ligament, the len^or vaginw femoris, and the sartoriiis are 
altsiettei). The latter mnsele extendi onto the notch below, uhieh tninsniits the 
external eiitaiveous nerve, and seiwirates the sii[>erior from the 'interior itij'rrior 
*f)ine. From the hitter, «ttiated almve the aeeljibnltiin, tlie stniljjht tendon of the 
reetil'i femoris and the lilfi-femoral hiind of the hip-joiiU take orinin. Below this 
spine and between it and the ilio-jjeef imiil eniiiienee. where the ilium ami (» piiliis 
meet, i-* seen the in/enor iHtir lutlf/i. This 'at >itii«lei] in front of, ami above, the 
aeeiahultim, aiwl is tniveix-d by the illo-p^uui ranTrfde. 

The crest ends Ix'hiiid in lh» jto^erior stiperior gjtine, whieh affords ligamentous 



isa 



THE HOSES. 



&(!et, onA three aiiperiop faoeti — a Iarp>, conrave, centnit ono for the trajicxjoid, 
and marginal ones lor the os magnum and trapeidum. r)(n>>ally, near the external 
angle it ihl-* a tuhiTcle for the exteiifor carpi radialis longiiH. That of the Ihirtl 
hiia a jiroraineiit projection, tlie styloid prore^;, at the onicr and upper angle of 
the dorsum, bchnv which the cxtcii>or ciirpi nidiiilii* hrevi^ i^ iiiwrttd. That of 
the fourth has two faeet* cxternullv, oorr('s]wndiiig to twi> inlcriDilly on the third, 
and, be>iides the niaiti fiii'.'t fur thi' micitorin [lUcvc, there is n hinnll fjiccl for the 
OS niii^iiim on the iMiter angk- Oiirwlly. The hii«<' <>t' the fj'lh hiis no fiioel inW-r- 
nully, but a tidxTiK'ily for ihe extenw)r carpi nhuirl:>. It* up|>cr <ii<l i» mm)<IIc- 
»liapi'<I and direelctl slightly niitunnl. 

OnHijif'ititin Iff ihc [tictacjirpal hiine!* iinti phalniipes pn^tHHlw fmni one priniar)' 
oenlrc in the :<hnft,an<l a seeondary <'eiitn- in I he b.i.-ei>f the firr'l nictncaqwl Imhic 
and of (he phiilange!. and in the head of the otht-r raetaeari>al^, 'I'hi- seeondarv 
ci-nlre joins the sthaft hy the ttventicth year. In the terminal phaUingen tlie 
ebaft centre begiiia la tfie distal end. 



THE PHALARQES. 

Of Ihe finirfecn jihalnnge.-i (" nink.-") (Figs. !":{, 175), eaeh finger eontains 
three and the thiunh twi'. I,ike all long bones, they have two extremities and a 
shaft. The ;(/i(f/?jf, semi-eyliiidric!il, are convex dorsally, and the rough margins 
of tiitr Hat palmar siirfaeeii give attachment to the theathH of the flexor tendons. 
The live of the /)-«f row nre the longest, and are lilightly curved longitudinally. 
The tliieker upper end, or fxi«e, has a tranKVer§ely elongated, concave artienlir 
facet (ylcnoiil crirlli/), and (he 'lintn! niiJ, Hatlentd truin iK'foi'e backward, has a 
facet prohtnjjed onto the piihiiur awpecl. .ind divided into two condyles by a 
groiivc. The four of the fri-niui rnrr, that uf the tliiinib being u-»nting, are 
smaller, but xiiiiiliir, except that the prcixini.d arlli-nhr fueet hn> n filight median 
ridge and two laloral depression* lo tit the eundyles of the fir:*t row. The five 
Urmlii'U or uiu/nai (from uiiffiii«, " u nail ") j>hnlftti(fr» liavo proximal extremities 
like those uf the leeond row. with the aildition uf a (ndninr ileprexsion for the 
long llexor tendon*. The .■'hufl taperM to th<' lliittened, expaixled, hor;se>hoe- 
KhajH-cl i]ist:d extreniitv, of which ilic smcxilli dnrsid surfiiee i>ii|ijMjits tile imil, 
and the rmigh iwlniiir !«urfai'«- llie ]"ilp of the fniger. 

Taken togellier, the phalanges of the middle fuigiT are the lungeAt, mid next 
those of tho ring, index, little linger, and thumb, in the order named. 



THE BONES OF THE LOWER LIMB. 

The honv pelvis inoludeK, besides the ."aonim and coccys, iilr<-ady described, 
the two hip-bones which form the pelcic yirtlh. Besklei* the lii|t-boii<-T^, the skel- 
eton of the lower limb comprises the femur in the thigh, ihe tibia and tibnin in 
tile leg, and thr? tarsal, metatarsal, and jihalangeal bnues in the toot. A large 
sesamoid bone, the patella, is found at the knee. 



THE HIP-BONE. 

The hip-hone (on rortt), or rut iniiomlnittum ('■ unnamed bone") (Figs. 177, 179), 
is irregular in furui anil nhajH d somewhat like the blade of a "enw-proiM-IIer, It 
is narrowed in iJie middle, whei-e the ncttiihu/nui, or ■"•K'ket lor the femur, is «i-n 
externally, and expanded above and below. The lar^'i- np|M-r portion forms the 
Jahe pth-is (" l>asin "), a part of the abdominal wall ; the lower purl ion, perforute«l 
hy the laiye Myro«/ ("shield-like") or 'jbtuiiitor {" !'Utjt\H-r")/ora>iini, form" the 
hilcRLl and front parts of the tnie ptr/fi», and curves iiiwaix) to meet iti« fellow. 
The hip-honc transmits the weight of the body to the femur. The thn>e jmrtii, 



THE UIP-BOXE. 



163 



ilium, iMi-hiuM, nml o« pubU, sopaniU' tii varly lifv, ankylosrtl in the utliilt ut tlm 
acetaliiiliiiii, w-Iutt! tlicy uiwl,arr cotivt-iiii-ntlv n-cdpnixiil ii» <lUliiict in liir ilwfriii- 
tion of ilii- Iximr. In fiilluwinfj tlur i!cwriiilii>n ImM lln' [Ktsli-riiir i>url of lue 
noicb ID tlic iict:tiil)iihun duMutvuni, in titv imlund jMwitioii uf tiiv Ikhic. 



The lUom. 

The itium ("twisted") U the hirge, npijor oxpatiflcMl portion, wlio^c lower limit 
fomi» ll«- U[>|KT tw<>-fif>Ini of ihfl acvtabtilntn, ami wlio-^c npjHT bonier, ih*^ rrrxt, 
nremat» timi; lips fur ulUc-lintCDt of tlw flat imijiclct- of llit- alKlonicii. Thi- prwt 
la iiinaouitf j-sUa\Mti, irrfpnbrly thicki-iii?«l, ami MilH-itta neons, 

Tn thfl oiiUt lip arc iittJK-hc-(] the tensor vagiiiie temoris in frtnit, iIk> ohIit|Uiiii 
externus in lh« ventml Iwlf, the lnti»siniii« in the dontiil half, nml the fclitti'jtl 
portion of the lu^ia lut« iu the «titirv length ; to the iniddle rJdgo, the oUicjuus 



■ ISM •■■■t 



Mart)! ion 
HSIftll anHt 



men <u*c* 

■en ariiic 




ami 

HOrCH 



Flo. 1T7.— The rlKht tilp t«Dc. oultr ■uifkcc. (TcnaLl 



in«>rnu.'< in the ventml twn-thirHs; In the inner lip, the tranflVersalia in the veo-j 
iral ihrt<<vfonrih!i, the qiiadnitiiB lumbonim aud erector apinae behind, and the 
iliae fn.-u;ia in the entire leiitrtl). 

The ereit ends in front in the prominent nntrrior snprrtor sptnr, to which the 
inguinal (Ponparl's) li^^ment, the tent^or vajrii"e femon^s, ami the sartoriti^ are 
atlaclK-d. The liitter mii-Tck' extend;' '-nto the noteli below, whteh tntnt^iiiitM the 
extcnuil cntnneons nerve, and tiepiinili-i thi- Kiij>erior from the <tii(rrir/r infrrhr 
epine. From the hilter. sitiMieil .ibovr the iieei.ihMliim. the I'lniighl tendon of the 
rectufs fcmori* mid the iliiKfemorjil Umd of the hip-joint take oripn. ISelow this 
B|iinc and hcitwM'ii it and the ilio-peelineul eitiiiieiiiii, \rhere the ilium and on pnbin 
meet, i* Hi'eii the injrrior lUitr iioti-h. Thi:* is Kitimteil in front of, siid nbove, ihe 
acetabiihim, and in ln(ver!X-<l by the ilio~|>Aoan nuisch'. 

The crest ends behind in the ftonlmor siifierior tpine, which affords h'ganientnus 




Ifi4 



THE BOXES. 



attachment. It 'm separnted by a blit;l)t itotch from tlii^ pontrrior htftrmr tftine, at 
tbc hiiiJcrmoot puint of the tmriculur »rtk-tilur aiiHiici-. Bclitw tliv l»ttt.T !|>iri« 
in tho ffrrat MToseitUic (" «icr<>-i»ctiiatii; ") nolvh, b<>iii)(l<-(] nlwve by llic ilium, 
bflow iiiitl in (rout by tbo ilorwil boiiicr iiJ' \\w im-biiiiii. 

Tho rxtrrtuil imrjncr, nr rlnrMuin, flul ur miiivi-x in t'i't)rit ami Iti-hiui), i*on<yivc in 
the miibtle, is marktil by tlic Kii[ti'riiir, niiiMIc, luid inttM'ior ^hitfuil lirK->, which 
foi-m th« b)wer liiuit ol' l\w ■•rijfiii of tin- glutei iimxinui.'^, dimIuh, mid luiiiimiisi, 
n>niKH'li\i'ly. Tho superior yhitnal line beginn at tlie rrest about 2 inches iii front 
of its (]or!<nl end, ami curv<?s downward to the hind i>art of tJie ^reat sciatic notch. 
To thf* lower jtart of the upace behind it llie pyriforuiis is often attached. The 
middle yliilf.ai lint curves backward ;ind ilowiiwurd fiijiii the crest, 1 inch behind 
its auterior end, to the uujwr border of the great sciatic notch. The inferior 
giuteal line pax^e^ bnckwam from just above the anterior inferior wi>inc to the front 
of the great sciatic notch. Between the inferior gluteal line unu the niarf;in of 



blTIMIHUS 



oiuouua 






U»TOIIIUB 



KOTua roaonm 




«UAOII*TUa 

■miHiHBflaiioau* 

■CHITIiaDIHOkU* 
UNO •>»*• 



OBTUaATOIt 
■NTIBHUa 

■c«Tua 

fkaooMiNia 

^TaAtilDALia 

aaDucToa Loxat^a 
ABBuCTOH ancvia 



ADSUCTOa W>BHWa 

fio. in.— Areai or miuDular attachment, oul«r votlkcc of riirbt hli^-bone. ITmtuL) 



tlic acetabulum, and a little behind the anterior inferior ^pine, is a rough surface 
for the reSeoted tendon of the rectus feraoris. 

On the internal turj'uce of the ilium is lieen in front a smooth, concave, triaii- 
gulur area, the Hiae Jonen, piving origin to the iliucus mu^icle. A smaller, uneven 
surface Ix'hind this is divided into an inferior 'Uiriridttr ("car-8hap<-d"i, carlilagi^- 
covert-d utirfacc for articulation with the Kiu-nuii, and a sujK-rior rough surface fur 
llic attachment of the jKJBtcrinr siicro-iliiic liguuicnls below and the crcclor sjiiuie 
nljovc. The iiiuc fu«)ta is limit^il Ix-hiw by the ly/o-pflfYjiiew^" ilio-pubnl") /iVif, 
which forms the brim of the true iMlvis and extends iK-lwecn the auricular 
ftuHacse and the "pine of the o^ pubis. Below the uuricnlnr ^nrfuc*' and the dorsal 
end of the ilio-|H-ctincii] Hue i-t a siunil, HmiH)th area of the ilium, which forms a 
small purt of the wall uf the true Jietvlfl. 



L 



THE HIP-BOXE. 



155 



The Ischium. 

The ttcAiitm ("hip") is HitUKln) ilot^o-iutV-iiorly. Siii>cTiorly it fnrmB twi>- 
fifthfi of the acetabulum on the <l<>r?al and Iomoi- umk^i, rix) m-iiriy iill of the iuid- 
arttcuUr pan of its floor ; and helow, it lomiiriali:i> in (hi- (uhertmti/. Th« latter in 
the thickest part of tlie hone, U|»on which thp IhxJv rcwti* in silting, and from which 
the itniDM (■' branch ") ascends to join thai of ihi- ow piihi,'* to a.-wist in hounding 
ihcolitunilor foninici). The trianjf'i'ar upp^r part, or /jodi/, pivHunls exlernaily, 
Ix'twccn the »(x'lHl>uhir rim an*) the iiilMTositv, a groove for the npiier horder of 
the ohliinilor extemus. Internally the body and the tiilierositv fumi a flattened 
j^iirfaw, wiiieii Ixjundii the true [wlvis hilcrjiUy, aud from which the obtunttor inler- 
iiiiM ariiitu'. 'rile ili]r»o>intcrnnl horder 4>f the body completes the jrrcat wucrw- 
M!tatin notch, which if limitci) below by the proniinent spine of the i»ohiiiin. To 
the ;*piiie the .tinall sciutic liKunient is attiiclied dor«illy, the cnccygew* and levator 
ani iuternally, ami ihegemelhiif'^tiiKTiorrhirKO-eMcnitilly, where thvpincL^croMedj 
by the intenial pudic vc^««li««nd iu'i^l-. The eartilagv^Iud email sciatic notch, ove 



*IITtlllOI< tUPC 



ftfirmrOH ih- 
finiBit •PiH( 







oBiiaion IN- 



PIKE OF laCHIUI 



Ti», IJfL— TTie rlahl hii>-boiii.'. Inntr ilitfticc, ITiwtul.l 



which the ohtiinitnr inlrnuis tendxn f;li<lt-.7i, w|mrates the spine from the tiilwnwity 
b^low. The tuhrrti'Hti prewnti* dorsnlly a roiifrh <]uadnite surface, fmm the iipjH'r 
and iMitcr portion of which the !<emi-membrant»us« arises, and from the lower and 
inner |wrt the semi-lend inoaus and biceps. This area is separated by a Iransverae 
ridpe from a pyriforni, iviipli surface in front of it, which is continuous with the 
lower and inner 1ii>rder of llie ranuis and jfives ori^'lu to the adductor magnus. 
The sharp inner lip of the tuberositv affords attachuicnl to the falciform prolonga- 
tion of the great sacro-sciatic liganieni, and from llie outer lip the tpiadrntus 
femoris arises. The ramu», flattened like the descending ramus of the os pubis, 
with which it is contintious, present* a thin upper nmr^in lii'irndinp the obturutor 
foramen, ai>d a thicker, everted, lower marpiu fi>r lijrnnientons aud muHi-ular 
ultaehment. l''n>m itK outer *uriiii-e the obturator exiernnri aud lulduiUnr miignus. 
arise, and from iti> inrier wurfacc iirisc the obturator int^-rnus, eoni>tnctur unrthmj, I 
cms peni#, awl erector penile, and, dorsalty, the tran^versns perinei. 




156 



THE BOXES. 



Tbe Os Pubis. 

The ogMi jnihU ("lioncs nf the |mlM'H") form the front wall of tlip ]»flv!g. 
Kacli ooitHiftt.s of a Har, rjiia-iraip bo<l_v, situated interimlly iiml joint'd widi the 
ilium au(l iechiiim, respective Iv, by two nimi, tlic horiiwutul utid descending. 
The ventral surface of the botlj/ and of ike »it»ccn(Uvij ramuK is rough for the 
origin of muficles. The corresjK»nding clorsil or prbw mtrftwc is sniuoth. From 
llio ventral i^urfiice arise tlie obtuniior cxtcnius, the pnicilis. und thi- three 
lulductorii; from the dorsal surface ariM.- the obtiinitor iiilcnius and levutur uiii. 



lUHSORUH 



TIUHCVaWtLI* 




FMM« PAHVtra 



ecu CHUB 

TK*HaVCN*U* 

pcniHtl 

LEV (Ton UH 
OaTUKATOIt [ITCIIHua 

Pio. in.— Atcuof miuculiirBtUicbinvat. Innvmrfiu-pof rliht )ilr>-bOTie^ (T^nit.) 

Tlie i»»WT border of t!ir rmnfifnnl iiutiie and ittcli'mtic niml of llic two sidf*, 
which fitrm tlii; pubic an-h, i» nntgli and more iir less evt-rli'ii, iwiMiciaHy in 
the fciiialc. The •mtrr hnrilrr <f ttir iviii and descend hiy riimiiH i8 narrow, 
unil bfjiimU tiic obturatwr foniuicn. The inner border of ihe juihir hody iire- 
wnts im cliiiigiitt'd, nvni siiriaci- whieh is joined by cartibgc- tu the opposite 
bone, forming llic jti/iii/i/ir/WJi ualilx. The troad, roiieli ujijjrr f/m-dn' of tlie 
IkmIv iir pidiir crrM !«lrflclii>fi ln>m the up[K'r end of the syniphy:>is, the oni/le, 
ourwunl 1i> llie pnmiinetit x/«W <f Ihc ok fiubi/i. To the crcsl an- atlnchetl tlie 
reelun alHlomiiiin and pyramidalin and tlie conjoined tendon ; to thi:- opine, tlie 
injfiiinal ll'oujXirlV) ligament. The horizonUd riimtm extii-nds from tlu- bmly to 
tile ilium at the ilioiwctineal eminence, and expiinds at its outer end to form 
the ventral fifth of the aeetabulum. It i^ more or less iriangnlaron seelion, and 
its upper bordei' is the pubic portion of the dio'pi-etineid line, to which Gimlieniat'o 
ligament and a jKirt of the cnnininiHl tendon arc attached inlernallv. The tri- 
anjfiilar surface in fn>nl of this line gives origin to the ]iectineus, ami is bounded 
Iwlow by the promincnl nbtrirtfnr ermt, which extends from llie pubic spine to the 
cotyloid notch. The umlcr surface' l)ouiidK the ubtunitor fonimen superiorly, aud 
present* externally the deep obli<|U« nfihtrator groove for the obturator vessels 
and nerve. 

The nertahiditni ("iiniall cup"), or rotyhid eiteity, i* « nearly hGmisphericJil 
cftvily which lookii outward, downward, and forward. It eonsit^ts of a horse- 



4 



THE HIP-BONE. 



167 




ihmtDE Ibr union nf (he tbtn ixinlDHii In 



xhiy^Bhapt-*! marRiniil iirtiriiliir imrtion, which artictitalc« with tlic femoral 

hraii, uml a ik-pn-vvcil ivritnil uiiil iiitVriwr iiou- 

nrtirtilar pMrtimi, wliiirh imlgi-^ « niu«. of fat. 

The H]>[H'r |Kirt of lliv iiiiirgiti is ^\w nlutito^t iiik) 

VMmi [»n>mlncnl ; [hu lower [Hirl U dcfii^teiil 

t\(iM.\ to the ohtiinilor foraiiipn, furniln^ thtt 

rolifloul milrh, whi<>)i i.* briflgeci acro*i I>_v the 

lTaji»v<'rw ligaineni, forming the eoti/hid foi-n' 

mien for ihfi {ta-tiiage of a nerve and vessels 

into tJie joint and to tlie head of the femur. 

To tlie margin of the ariicular jwrtion the 

cotyloid li^menl is attached, deepening the 

cavity BO that it is more ttiiin a lirmi«phcr«, 

atvl oubside of this the i:»|>Kii1ur lii^inienl ari<Te». 

The nhiumtiyr or llii/r'iirf jhranu-n , liclow an*! 
intcrual to the sivlnhuhim. I;* fornuil by ami 
situut«-<l iM-twcen tlu-- ischium ami os pubis. It 
i* clotwd by the iihrntw ohtnnitor membmnc, 
which is attJtcliMl to itM iiiiir)rii)H cxo'iit ll<^nr 
the priHive for tht' ol>titr)iti)r vc-»«i'ls udiI nerve, 
in \U up|)er marjrin. In the tVmiilc it !.« bnmd 
iinti I riaiit;(ilar, in thi- inah- oval and eloiijrated downward and biickwanl. 

The ihac orest, [Hil)ic spine, tnlM-rowily nf ihc ischiimi, and combini-d ram! 
of the ort pubis and ist-hiiim (honnding the pt^rineimi) ran lie felt snbcdtaiicouisly. 
The anterior 8«porior iliae spine and the pubie spine are of great ini|)ortan(H' an 
landmari<H. The hip-bone in nineh thickened alonp the lines nf grwitert pr(i«»iirp 
— *', e., between the aiiriwilar surface and the upper part of ttie m-etsbnlnm and 
the tuberosity of the iKehium. There ic a thick ridge running from tlic Jioi-labn- 
Inm to the iliac cwBt, but the centre of the iliac foisa »s well as of the acelnbn* 
Itim is thin. 

OmafieatioK (Fig. ISl) tukes place in cartilage from a centre for mrli of the 
three parta, Jliui.., ischium, and os pubis. A M'condary ecntre apjwurs later in 
the Y-^ha, ed cartilage, wh they meet in the lUvtHbnhim. Thi" t^tij^e.H with and 
joins togrtlur ihc thrc-e parts from tin- .*i\Ufnth to the twi-ntji'lh yeiir, Seenudiiry 
miclei appenr fiir the iliac crtwt, flie .-interior inft^rior i<|iini', the iwliial tubenwity, 
and tile pubie erciil from the lifleenth yejtr on, and unite willi tlie main Ihiim; 
aiwut the twentieth yiiir. 

THE PELVIS. 

lite pelvis (Figs. 182, 183), whowt con»itituent parts, the two hip-bonee. con- 
nected behind by the saeriuii ami coccyx, lia\"c sdreudy Ix-cn described, is divided 
into two parts by a plane [wising ihningh the sitcnil promontory behind, the ilin- 
(x-ctineid lim-s lab^rnlly, and tiu' pnbie <Tesls in front. The part above this 
plane, nmi[>Oi»e<I "f the ili!i, belongs lo the al)ilc)tiiin:ii eavilv, bnl is e-nlh-d the 
/«/** pttpiK The limiting line is ealle<l the brim, iukI the ineliidnl hi'nrt-shiip<-il 
spaoe the I'n/ri of the lower part, or true pdn'm. The outM, or lower eirtruin- 
ference of the j>e!vie nnvity, presents three prominences — the ischinl tuberosities 
laterally and the eo«Tyx iK-hind — semraied by tlin-e notches, the pnbi<' an-h in 
fn>ni ami the two sciatic notches behind. The iiuhiv an-h is the iingnliir sjiaee 
in front lieneath the symphysis and bounded by the combined rami of rhe isehia 
and osiia pnbis. The sciatic notches are bridg<'d acriiss and convert*-)! into I'nni- 
mina by the sacro-sciatic ligaments, which bound the outlet of the pelvis a.s Well 
as th« peiincum dorso-laterally. 

The eaeittf of the pelvis is shallow fIi-2 inches) in front, where it is bounded 
by tlie OS pubis, and (leepcst (o-.l^ inches) behind, where the curved sacrum and 
coccyx fonn Jtn bony wall. The isehia form (he Uiteral walls. The oris of the 



L 



^m^ 



168 



THE BONES. 



IK■Ivi^, or the line drawn thnmgb tht- ccntR-s of the nluiics of th« inlet, ■ 
ami oiillvl of till? pelvic, \^ oiirvLtl willi lU comnvily Inrwiinl. 

Tlic pmiiion oj tht privU in tlic tercet iiltitiKir of lii<- Ixxiy is 60 liltod or 
inclined thit thv plane oi' tJic inlfl lonni* un uiigU- of OO' ty 60° with tlie bori- 




PlD. M.— The plann of tha pclTla. {Tcamt.) 



eou, M that n ltti<> drawn ut right angles to tbf ocntn- of (h« plane of the inK>t, 
if pnilongod iipwiin), wonl<l iiImhii iin-ct ibo iiinbilicii>(. Kiirlbcrmore, tht- bnw 
of Ihe »it'rinii m riiii^tHl jiboiit .'ij indu^* iiljovc ibi- iipjicr nuirgiii of ibc j^jm- 
phy»is pubis, niid (he tip of tlic whx-vx is i— 1 inch iibove the b>wpr end of 
the sympbytiiB. Tbt* plane of iIk- onik-t is more neurly burizontnl, forming an 




Flo. MB.— The [cmtic pctvl*. nar view. |Ti>»iut) 

un^lo of iibout 15* with the horizon. Tiii>i tilting of tbo [wlvis brlngp the sacrum 
more or lc*t on lop, where, however, it docs not form the keystone of the arch, 
for it« widcj«t oitpcct looks ilowiiwunl into the pelvis ; nnd the bone is held in 
pliiec mainly by the strong posterior «ifro-ili»c liganienlir, and only ^!iph1ly by 
the projection of the lower anil ventral inaiyinif of die imnetilar snrfai-e" of the 
ilintn. The weight of the body is tnmi'mitli'd from the wuTo-iliiie ji'int in an 
arch along the niu^»ive iliii-)>ecltneiil lino to tiie acetabulum in the i^tambng posi* 





TJIE FEMiJ{. 



169 



ion, and to \he ■''c-hial tuberoiiicips in tbe flitliug; posture. The horiu>ntaI rami 
of the oesa |)iibis form ihe couuter-an^hfs or lies to the former arch, ihe comWricd 
ischial and piibk- mini to tlie latter arch. The pressure along the arches arid 
conoter-ardips when the hones arc softened by rirlieis or osleomaiacia causes 
various dvformilicT! of the pelvL-4. Th« pelvis ix admimbtv ndaptptl for a variety 
of functions. To nx-eivc and transmit the weight of the body to the lower 
rxtn-m!ito)i in Ktumling, ami to the iM-hial tuberosities in bitting, it is pro- 
vtdc^l with veri- strong ridges of bone between the very secure Hacro-iliac 
nniciil:ition» ami the acH-tnbnlu and if^cbial tuberosities. To prevent the^e arched 
ridjjoi fnun collap«iuK from prrssure. lliey are conncclvd lueether anteriorly by the 
eoiiutiT-arrhos, which mwt at the sympbysiii. In thl* way n rjitber shallow cavity 
ii» fumuHl, whieli contains and protect* tht- jM-ivtc vinciTa, and is so nhaiJMl as lo 
allniv of Ihe |uL'(^g<* of tin? foMal head in jHiriiiritinn. The lliirinjr ilia aUn help 
to HHp(>i)rt i\w alHlnniinal vi-i-era, and thi> ividi- rxpanst' of bone pnespnl* a large 
snrfuoe for nmscniar attachment under cotulitiiiii» favorable for leverage. 

Sex differrncrii relate lo both sijte ami form. In (he finiiiU- the hones are 
lighter aiul smoother. The eiivitv is br<>jwler, nmn- (-a|)u<'i"ii.'<, ami less deep. 
The snnnhy.iiH ii> mil i«» (Ufp, the pubic arch wider, the i.-ehial titbt-iviflilies more 
expanded, and ihc stieriint fbittcr and brnader, Th4- ^ueral promontory is less 
ppijectinif, giving the pelvic inlet a more oval .-hn|M'. The ihj r<)id loramina are 
more triangular. The diiren-mfn of sex are imtiecabli' in early lift- ; hut in gen- 
eral all pelves are more or les^ of (he male typ until about pulieriy, when llw! 
female eharaeleri.-<ties beei^une marked. 

Tlie following table represents the average measurements of the pclvl* ID 
inches : 



I»Bni«l«>*, 


lUl*. 


fVmal*. 


BrlDL. 


Cavltr. 


OnilM. 


Brttr. 

fi 

4 

5 


CiTltjr. Outlet. 




( 


If 


It 

i 


£ 
61 




OUiqup <fram (he aacia-iliae jeAtA to th« tlio-pcninc*! 


4 

4} 



I 



THE FEMUR. 

The /rmur (Fig!'. ISl, 1S6), llie Irii^-st and h>ngc*it bone in llie body, is 
inrlinetl inward and slightly huekw.iril, t^n as to nppiviaeh ils fellow infenorlv. It 
extends ln-tween nnd arlieulaiejt wilh the Iii|i-lMUie siIkivc jiml ihe tibi:i Ixlow. 

The txpper atreuiitt/ includes the hi-au!, tiic m'ck, and the two tmrhanlers, 
which gt%ea1l3ehment to the mfator niuscle«. The nee* extends inwanl. upward, 
and "iijfhdv furwiin! from the «bufl to the liead. It is eompresm-d fri<iii iH'fon' 
backward, out t.'X|Ktniled vertically, esixcliilly when' ii joini< the ^liat't. ll> length 
is greater behind and below, and it i.i concave behimi. lis axis forms an angle of 
12-'>° with that of ihe shafi. A\ birth this angle averages 160°. Dnring growth, 
owing to the weight of tin- body, it liecrea.ict tu from l-H)** to I U)" ; luii afier 
growth is eimipleted, it remain^, lixod. It is less in lemak-!< and short subj«-ers. 
The Iteail in received Into the acetithuhini of the hip-lM>iic. ll forms nxirc- than 
balf a sphere, and is covered with cartilage, e.\t«pi ai a small pit hebind and 
below the oeutpc, to the upper half of which the liganienlum tere.s iii attached. Al 
the junction of the neck and shaft the two troehantei-s project. The givat (ro- 
efumttr is a stout, fpiadri lateral pUiie, continuous with the outer .surface of the 
sIiaA, which reaches nearly to tht- liighest level of the neck. On its outer surface 
the gluteus medins is attached to an oblitpie line esieuding don nward and fontard 
from its ddrso^sujwrior angle. Tiic lower limit of this surface and the up|H'r 
extent of the vastus externus are marked by u horizontal line, which, in front of 
the trochanter, turns upwanl to an eminence, the tuherelt, at the junction of the 
tfoclmnlvr with the neck nnteriorlv. Internal to the trochanter and Ix-tuecn it 




160 



THE BOXES. 



anil this neck is the ileep digilnl or Irtirhanleric Jottm, which rccoives the tendoa 
of llii- obtiiraror exl(-riiii». Above and in front of this foMi«i the obturator inter- 
im:^ and the gomelli iiiv iiiwrt^d. Beiiiud the lalli-r tho j>yritiirniis is inserted on 
thr narrow five uppT f/m-rhr. The gbilnis niinimii^ h iiiMiTttni uiHin the unterior 
liordtr, while the thick, n^undcd poxlerlnr hordrr is contiiiiioiiN willi the jioiierior 
intertrochanteric tine, which riiii:!i downward and inward to the small trochanter 



oarunATeti IIITUIMU* 

>HD BCKILLI 



mtiroiuiia 



,'+i 



CH>nTtM 



Eh"- 



' OOMO. 




Pia. IM^Thc rlfbl femar. (tout iltw. (TtiHiil.) 



Via. ISO.— Arru of muiPitUr Mtarhnfnt, Tv&Uml 
mirfnc* of rixlit rciuur. iTmliil ) 



and limits the neck behind. The ^mnfl trocJumlir, receiving tlie insertion of the 
ilio-peoiie, projects &» n nvnimidal eminences from the dorso-intemal nspect, where 
t!ic lower cn<I of the nrcK joint? the fiiad. The ntitrrior inlrrlrnchnnteric livf limita 
the neck in front, and ffive« altaehmi'Dt to the thiekcnitl front part of the cap- 
snlur lipament. It is the upper ^Kirt of (he npiral line, above the small trochanter. 
The spinil line nioK from the tubercle of the femur downward and inwanl to lh« 
linea at^pera, pas^inf; a little in front of the small trochanter. 



THE FEMUR, 



161 



The i^itjl, ari'Iiii! ii>iiv<-xlv fitrwarc], in n<-Arly oytinrlricnl, <-xi>>|»t for a tlntu-iiiii^ 
in front aDtl a |mimiiit-iic biiltrtiw-rulgi-, tli<: linra aHjH^rn (" nidgli liiio") hfliiitil ; 
so thai tlirei- rsilier iii<ii.itiii(-t .-iiirfiiLv^, a ventral and two 1»«t»I, may lie din- 
tin^ui/rlied, wliicli ari> itiven-d t\v iJk- lliree vasii muM^lpi. Tiic shait fX|iatitU aa 
it anpnMcbt>s tli« Inwer exirt'inily. The duea atpcra ]ini-»enl^ in Uie i«ntral iliird 
o upa uid a rtH^li, narn>w interval, often calletl ttic middle lip. In die uj>per 




ruHNia 
■ -1 




.ftrraocHiHiui 



Hoi Utt.— Tb* rl^l ftnnisr, nu vlaw. (Twtiit,) 



■CHiucniBiiaiioau* thboush thc 

Pin. tfn.—Amu i>f miiai-iilar ullMlunoni. doratl 
Mpwl "f rl«lil fvmiii. tTvtlul.) 



ifatrd tlie ftxU'ninl li|> extends tip to the }rrcat I roclmnter a» tlic promiiiont ghilral 
ritlijr fi)r rill! ^tittcufi maximn)% Tlic intcriml lip is coniiiiiioii!^ with tlit! «pim1 
liue, while u thinl lin<^. Riviiiji inwrlinn In (In* iH-clineiin, awnid!* to (lit* ^iimll 
tmdiauter from tlw ititcmn^tliat* i^)kioc. InltTiorly ftic Iwu lijw diverge and 
extend Ii» the coitdyk-« a* tho rxtmial and inln-^inl cmidghr ridgftt, t^rH-Uvi^m^ a flat 
trian^nlnr area, the flocir of thc iijiiwr larl nf the |H>pliteal spaw. Tin- inner 
ift interraptMl in tlie np|ier part liy the era'^ing of tlie femoral vesN>le, 
It 




162 



THE BOXES. 



r 



mill fiids below in the sharp adductor luhfrde, to whioh the lowi^i fibrw; of tlio 
luldiii'liir iuu);iiiit< an> attachinl. Ihe eaneit of the xulrieiit nrtfrif is dinx!t«Hl ii[»wunl 
ill tin- liiK-ii a.-<iHni a litili- above its centre. Thi? following iuuk-W, bt-^idivi tb'w« 
(ilrciiiK- iiifnlioned are attached to llic liliea abpera and it- pmlunjra'.ion.- : To lb« 
iimt-r lip U attuchod the vai'ttis iDleniii!^, atid to its loiter twu-third^i the aildiii>- 
tor !onj!:tis ; xo the outer li|> the vutitiis externum ; aud to its lower two-lhirdn and 
the external rondvlur rid|;e the sh<)rt liem! of the bic-e|M-. Th<; nddiiclor mtignufl 
is inserted l>elnw into the inner emidyliir ridge and the iiddiioioi- tuberele. in tlie 
middle third to the inteniH-diiile siiae*-, uiid ^ii(KTiurlj' jiwt inteiriul to the gluteal 
ridfie, as tJir a;; the •]uadniliis rem'irii». 'I'lir adductor brevi» i^ iitUiched !<■ the 
upjxr third of the interiTUHlinic .■.|iiii'<' below and external to ihe pi'etineus. A 
fiiint line, the liiu'/i i/iinilni/i, liir in.-i'riiciii of the (jUiiihiiltir' feinorii, i» siiineliines 
visible, mid [imsscs iipwiinl fiMiii tin- nuter side of llie miiiiII true ban ter lo the 
midiile of the posterior inlerlr(Krhant*-rie line, where the luhei-fli' nj' flu- ipuiilrntus 
K ^otuetiine'f isoi-n. I'art of the iliaciiH i» allaehed to an an-a Ijelow the small tro- 
clmntvr, int<-riial to the peetineiis. 

Till- hii-rr I'j-I n-m!t II prfKcntn lifi r<mdi/l<v, external and internal, most proriii- 
ni-nl behind, where tliey are seiiaiated by the deep iutfii-'iiiihifiir uotrli, Mliile In 
front tliey are iinitiHl by the trnch/fay (artieuUir) "iirjaei- for th(? [Xitclla. 'I'be jiart 
of the troehlea external to its vertieal groove is the lat^r, and is very prominent 
aloDK its outer «dge, sen-iiig to resist tlje tendency to outward disloeation of the 
patella. Continuous with tlic tnwhlea are the eartilagc-elad lower and dorsal sur- 
laee- of tJie condyles, which, though of dlUcrent curvatures in dilTerent parts, articu- 
late with the tibia. The external eonilyle is the brimder, the internal the nar- 
rower and the more prominent lalenilly and behind, while in from it bends outward 
to the piitellar >-nrfii<'<'. In the natural <)r imlined position of llu- bone the lower 
^iirfaeefi of tin- two londyles are in the sunc plane ; bill, if the Ixine is held verti- 
eiilly, the inner i* the lower. On tlur Interul unrfuce of euoh condyle the oor- 
respondinji lakTiil lijjninont of the kneo-joini i* atlaelied Ion rough tubrra»Hy. 
IJelow the outer tiilM-nwity the ]M)plitenj' ari>ef ('nun a <lepre-,Mon, from whieh u 
groove |uu<Mii^ baelcw:inl aii<1 slightlv iipwiiitl in iH'eupied by the tendon of the 
miisele in llrxion of the knee. To the mtvial siirfiiei-s bnundliig the iiitereoiidvliir 
notch the enieial ligunieiiis are aitaeheil, the (interior to the external eonilyle 
liehind, the ]Kisterior to the inti^riial condyle in fronL Iinmedinlely above ili« 
eondyles on the jwisterior snrfiiee the two heads of the gasfrocneroiiis nin.- 
arise, and above its outer head is the origin of the plantaris. 

The great iroehanter, the two eondylis, mid, during flexion, the trochl 
surface for the patella, are the only subcutaneous parts of the bone. The g 
trochanter is an imporiant landmark. 

The femnr averages IM inches in length in the Kuropeati male, and I" inches in 
the female. It Is inclined inwant at an angle of about 9° with the rsigitlal phme 
in the nude, mid at a grt-nter angle in the female. The femur prcents an anple 
of lofsion lii-lwern ii^ upper an<! lower extremities, nitigiiig belween 5"^ and 20"*, 
bill in till- oppD^iir diri-etioii to ihal of the humerus. Tlie himelhe of the ean- 
eelloiis tissue at the iLpjM'r exireniitv, which spring from (be upper end vf the 
shaft and tJic lower side ol' the neek internally, iiikI tli<- njijier i-nd of the sliaH 
externally, nidiale inward to the In-nd and oniwanl to the great. Inx-banter. They 
thus cross one another in aivhes whieh strengtlu'n Ihe neek of ihe bone, through 
which the weight of the bixly is tnmsmiili'd from Ihe heail to the shaft. A nearly 
vertieal plate of eom|>aet l>i>ne {i-iiUnr fiinorale, " feiiionil spur") projecLs into the 
interior, toward the gi-eat Inshanter, from .1 little in front of the small triK-hanter, 
and strengthens the concave side of the neek. It is liable to absorption in old 
see. The depression for the ligamentnm teres is wanting in a small oroportion 
ot eases, aiMl in a still smaller number Is replaced by a tnlKTcle. Ttie gluteal 
ridge is sonietimeH so prominent as to be calleil the ihu'd trocfutiifrr. 

Omification oceiirs in tlie shaft from one centre, whieh appears very varly. 
The lower epiphysis uppeiirv tw a single eentre. One oiler another centres ap|>ear 



4 



iiyie 
ih«^ 
iselefl 

leail 
rea« 



THE TIBIA. 



163 



fur the Iiea<! and th« grc«t and small tnx'luiiHuw. Hk-w join tli* i^lmfl n^ fnl- 
lovrs : ffmall trociiaiiU-r, M-vi-nlwntli y«ir ; jf rt-jit inirliniilir, i-ij^liti-tiitli vcar ; l»ii<i, 
ninvtvciilh year; oomivIiT.'*, twenlictli to twwity-tirst yt-Jir. Tlu- iiwk is an <iut- 
t^iwth I'ruta ihe abatt. Tiic line v>^ ftiitioii of ilio condylar ejtijthysU with the 
i>hiifl LH below t)i€ adductor tuboivtc mid tlie origins of t)i« gaHtnicneniius muwli% 



THE PATELLA. 

The prt/<//a(" little dish "), or tHrt--;><iii(Fips. 1*8, l89Xif(a Homned, triaogii- 
larBesamoid boot' id the ({iiudrioeiM extensor tvndountllic front of the knee^juiiil. 



M«C 





Pm. m— ni# right pptf I1&, Tcntnl «nrftc«. 
tTOHUL) 



tv*. IW.'-Tho rlEbi pairiu, •jorml (urlfcc*. 



Ttfl slifthtly convex ttmiral mirfm-e. is loii^itudiually proovtd by the fihroue expiin- 
nioii of the teoiloD. It^t ttorxiil KHi-f<ipf i^ montlv cartilage-clad, to nrticutute with 
the trockleur Hurfiwe of ihi? foiimr, and is dividttl by a vertical ridjic into a larn*' 
oiit<T, tioiicavo portion and a smallor iniit^r, convex one, to itrlieiilute with itiv 
outer and inner sides, resjxKttively, of the inn-hiear surface. The upprr bonlir, or 
base, is bevelled io front, and gives iii»c>rlion to the tcodoDfi of the niui«fk'it com- 
poian^ the quadriceps exteaaor. The njirx, 
ilirectcsi downwanl, and llie border on either 
»idc of it jnve attachment to the ligatnenlnm 
)vtt<-llii-. while the narrow, roush, non-artic- 
uLirareanf llic<lorwil sur&co above the a|>ex 
in ill relation to a mum of fltt. In front ot 
the [Kttelta i^ a burst scpanitins it from the 
skin. The entire articular surface \s not in 
contact with tin- ft-nmrnt any tim*-, but one 
part alVr inioiher a."( ihc knee is moved. 

Tlie pcilella is liitbifr to iTTHWvcrsc fract- 
ure from muscular action, and, »» it« 
bloud-aupply comes larp'ly from alxivo, 
care should be taken in dealing with the upper frajjmcnt not to Htmngtilatc it. 




fill. v*>.—'\'\f ui'iur HirDiec of Ilto rtEtil 
(Iblm. «TMtnt.> 



THE TIBIA. 

The tibia ("fihin") (Fig*. 190-194} i.t the inner, Iarp?r, and more anterior 
uf the bones of tliw leg, and conveys the weight of die body from the fvtnur to 
the astragalug. 

The »{}per rxtmnHy, or hrad, is thick and inclined trlightly backward aljovc. 
It is expanded tin each >ii<Ie into a niac^ive fi.iberni'ily, whose upper ai:|KX't pnx-nts 
a slightly coneave nrttcuhir surface, which receives one of the conilyicw i>f the 
femur. Of these artii-ulrn- Kurfnwf, the inner is toiijirr fi'oni before buckwiird and 
more concave; the outer is itmaller. flatter, ami more circular. Bnlh are fliitlcncil 
peripherally, where tin- M.'niilnnar fibri>-<'iirtiia^e« rettt n\mn theni and rIeciHtn the 
socket for the femonil condyleis. Projecting upward, between these surfaces, in 



L_ 



164 



TilK BONES. 



tlio Jt/«nf of the til>ia, which is laterally Mfid. To rotigh dopronsionrt betwf^n tt 
artieiiliir •iiirfnt-pf- aix- attached in fnint iif the spine the anteriur rnicial lijianient 
anil llif untfriiii- fxtri'mitii's of the stmniiiiar cnrtila^n, ;iml l)chiii<i the sjiint- iht- 
ixK^terior onieial li^fimieni aiul the po(-terior exlfeiiiilie!; of the ui.'ii>iliinai' carti- 
liiftojs. Tlie <lepret«ion lii'hintl tlic spine is contmueil huekward into a iiolcli, the 
jiojtlilriil jioffA, which st-jKinUe-s the tubcrositiet poi-teriorlv. In i'nmt the tiiWr- 
iiKilie* aw contiDtiuii;^, and lonn on the uiitvrior titirliu'e ot the head n triaiiKnIar 
area, whuw ajx-x |M»inl» ihtwMwan! timl mils at (he tuf/crvU: The hiwer end of 
the lalttrr |^iv(-» utttichtnent In llie li^iniiiitnin |>utelltc; 'lU upper siuuoth part is 



OUTtH 

•TllfltO 



IINNEB TU- 
9t"OBlT» 



ANTCnO^EKtEH 
Nil BOHDCn 



nine HO -IN TEH 
M*L •OnSEB 



OUTCH 

■kiuoiu* 




IHNCH 
WkhLtOUM 



cnuaiB 



BIBOHCUa 



riTENSOB 
OieirDRUM 



CVTCfOOB 

PBOPHIUB 



BtBOBtua 
■BEVIB ' ' 



rCBONCUB 
rEBTIiTB 




Vw. tni— Tile riKin tIMB ftiid flbiiln In llx'lr ii<-t- 
mHl rrlBtlona, Irrmt view. (llMlULvd Or^ii Tr>lnl ) 



Fm.lSl.— Ari»3orinUKiilBrnttaclinivnt.&nMirinF 

miH'rl i>f Iliv llliln imil iDiuiL 






separatetl from the ligament hy a bursa. I'imhi the tnl»crclp itip liody rests in 
kneeling. At the outer angle of thii triiuifiriliir Miitiici- !,■• a pirtinineiu-e to which 
the itio-tihia) hand of the fascia lata is uttnelnil. Thi- larjjer, inlernnl tidxToeity 
is markecl liehind hv a horizontal groove fur llie iii.-ertion of the '^^mi-momhra- 
nostiH tendon, and ifie exteniJil tnheroNity ]ire-M-iiI.t [Mwteni-exlernally a i-onnded 
itiiirHtnr fncft for the hejid of the fihiila. 

The three-sided ifhtifl of the tibia {>• very thick idM)Ve and laiiei-s towani the 
lower third, where it ug^ain expands sii^ihtly. The iulrrifil Mirjai^ i;* convex and 
i^ubciituntHiiK, except at the up|KT eiid, where, iiitcnial to the tuberclo, the sar- 



THF. TIBIA. 



165 



tonus, 0;rai'ili.'«, nnd semi-iondinofttit teniloiis art attached in llip unlcr namoil friHii 
atnive uownwiinl. Tlie ejtU'mal Kurjnit is coitcavc in it* iipiwr twtv-tliinU, wliore 
it jcives •>rifciD to tho tibialis anterior, conves Iielow, wlicre it Iowk« inwrv furwiird 
aD<l is i.-oveivd by tl(p pstensor tonctons. On llio pnntrriof imrfarf tlic jxipIili-'itM is 
iiLii-rtcil nn a tmngtilar an>a at tho ii)>per vad, itmittxl Ix-low by thv Mufttt thu, 
wbicb (uis-w- fr^mi tbp fibular fawl tlowiiwani ami iiiwiinl In tlic inli-nial W;nler, 
ami givi'i^ altachniunt tc tbc siAvhh nmiicU'. B«-luw tliv obli(|iiv liitr lbi:> ^iirfuiv i.i 




OUTCM 

PHC<f:99 



■EVia«E4t'_ 



•■GEM 



■il' MSTtllO.IIi 

friHHOl •«IID(I> 



OUTIB 
AL1-EQiU« 

anoovL roB 

m. 181— The rishi Ublaaiiil flbuU Id Ihdr nor- 
mal nlMloiii^ teat nvw. iTolut.! 




rLCHDII 

i,onau> 



na.lM.— AnM of mwrrilur "iimliinriii. in*- 
l«r1(iT lupMl or tli« Itblaaud niuiln. 



^ if 



diviikit by n loufjiltKliii.'il Tulffv into iin inner portion viving ori^n to the flexor 
kifkffiiK flif^tonim, ami tin ^l(H^■^ (iinlion, frtnu wliieb ari^vs the tiliialim posterior. 
I tin- ii)t|)i-r |Kirl iif tliif .<nriiiri' niiil biloiv tbf oWiqne line is foiiinl the large 
j'lir'itHfH I'll- llif itii/rirnl nrtfft/, <liri'irtfi! ilownwnril. Tlie iinl'-rinr f/onlrr, or xfiiii, 
eimiiMfi«-ing above, just 1n-lii\v lh<- tnlx-rtrb-, i;^ siilx-iit«neoiii=, HtiitioUK. an<) >-har{> 
in its upik-r twn-ibiiiln, nmnileil in its lower Ibini, where it ]iii*>es to the fi\>nt of 
the internal maileolns, Tlie f^xUmnf or hJerosM^uA In/rOrr gives iittaHimeiit to the 
'nteroseeouB membrane ami bifiircateii near the lower liiul, Uuis enelosing a triuu- 




Itttt 



THE noXES, 



[jiiliir area for the inferior iiitt'r<»seuii^ liKumritt. TIic tnifmal honler «xlciida 
t'rimi ilif Imek ol' (lie inlfriiiil UiiK-nwity iibovt- to ilie Iwwrk of the iDtvrniil tiialle- 
oliix bt-likw. TIk' rnii-rti.'il liiU'iul li^iiiK'iit is ultJivhcd to it« upgivr 3 inclitv, the 
soloiii^ riiiiM!])' Ill its iniiMii- lliinl. 

The ffiii--er fxlmnUi/ is Mmx-what iiuiidrilati'nil, ami i-% i'X))U»il<^] I raii»v<;n«.'lv. 
It is |ir(ilfni{ju(I clownwnni, iiiti'i-tialh', as a flalliKh, niilH'iitiint'ouM proww, tfic 
iiiti-rniit iiKilfcolu-x, from the tip and martfinw of whioh the internal lateral li^umi-iit 
of the iitiklc ari.->ert. The fore |mrt of ita external unrfaee h ariienlar, for tin* 
inner latenil faeet of the a'stragaliis, hihI ik continiions with it« inferior i|n:ulri- 
lateral artiriiUir ■itirt'aee, which artieulaleti with the upper Hirfaei- of the a-itray- 
aliip. This inferior fiicot is eoueiive fniiu before bavkwaril, and i§ narrower, and 
descends lower behind tlian in front. Behind the niidleoluiE is a groove for the 
tibliili)' posterior and the flexor loiijifni? digitonini. while farther exteniatlv tlie 
flexor lonjrnn hiillueiH ^liRhtlv frniove« the (Mii*terior bonier. The exlenial siir- 
(Jire «C the lower extremity of the bone pn-si-nts nt its lower end a narrow artie- 
nlar iin-», winch arlliiilale* with iln- fdjula. This urea U (Mnlinuoiis with tlie 
infiTior artienltir siirfnw. and nbuvu it the nilter surfaee if rtmgh for Itgnments 
wliieli itttaeh it to the libnla. 

The tibia i.-< lwi.ticd, nn that when the axi.'< of tliE' upper end i.-< tmnKverw lltnt 
of the lower end i^ inclined from without iuwani and forward at an angle aver- 
aging 5°-^'", but :tometimes varving between 0" and 48''', 

(hnilieaHon. — Each epiphv->is(i*iitie^ from a ninKleeentre. That ill the nppor 
end incUides the tul»ere!e and appi-ars lirnt. The lower end nnites with iht- shaft 
at the eighteenth or nineteenth year, the upper end in the twenty-firat or (wenty- 
lieeond year. 



THE FIBULA. 

The pmtn ("elasp" or "brace"} (FigK llll, 193) ip the slender outer bonT 
of the leg. It* Greek name \i^ pniinr, tlie adjective from which (" ]H?n>iieal " | in 
synonynioiiH with "fibular." It reaches lower than, but nota»^ high as, the tibia. 
Its np]H'r end is iH'hind the plane of tlit- lower end, and ilj' ^haft is slightly curved 
and very \-arI)ible in itj» eontonr. 

The ujijuT fj-trrmil;/ or liftiil is irn-guhirlv exjiandeil, and pr('*enl^ above and 
internally a Hniall olitii|itclv placed articular fiiei't, looking npwarc], iuwani, and 
torwani, artii-iilaliim with the liiw^t on the oilier tiibcrowlty of the tibia. Bi-lniKi 
and nlijihtly external to the facet rises a omiieiil emineiKH-, the idifhlr! jinm-KH, to 
which the short I'xiinial Intend ligament of the knee in attaehetl, while to a slight 
deprcrirtion in front of and external to it are attached the external lateral ligament 
and the tendfin of the biceps. 

The loiffc ejrtiTniita Is a ihiek pvramidal jircKThs which forms the cxfeinal 
mrilMug ("little hammer"). The latter is lower and more (Kwiterior than llie 
internal malleolnis. Its linirr mifjarr jiresent? in front u triangular facet for 
articulation wltli tlie outer facet on the astragalus, above which the cartilage- 
elail surface is conlinm^l npwanl for n quarter of an inch for articnhitioii with 
the tibia. ,\bove the articular surface is a rough triangular art-a for the inferior 
interosseous ligament. Iti-hind the fac^-t is a rough depression for the altach- 
nieiil and rectfplion of the jHisterior faseicuhi'' of the external latcnil ligament 
of the ankle. The fmKlrrinr mtyfitff is gnx>ved for the tetiiir.n> of tli<- (H'ronei 
lungiis and lirevis. Tlie fxlrriml mn-fiirr is siib<'ntaneous and <'ontinii(nis with a 
subcutaneous triangular surface ta|H!ring iipwanl fur two or thive inches upon tliv 
iihafl. 

The shaft hiLi four variable surfaces, each giving origin to n muscle or a grotip 
of mu^elce which produce a particular motion of the flint. The four borders 
limiting these surfaces give attachment to flbroua septa separating the musides or 
muaele-groiipe. The lower fourth of the shaft is twisted outward. The well- 
marked itulrrt^-txternal border begins in front of the head, and bifurcates in the 



L 




OF THE foot: 

lower fourth to inclmlr tliv truing)il»r fitibctitum-au« Kiirfucp iilwvv tuvritu'iicil as 
beiDj; continiM>iis wild tlit- outi^r «iir(iii-« of lliv mulk-ulcif. To it U iittudicd the 
anterior tibial riutcia wliioli sepitnitf* the ^-roiici loii^fiu ami brevic, winch pronate 
the toot aiKl tK-ciipv tlw rrtrrtiiif or jirontitor KUrfnrr, fnmi tin? cxtviisorc-s lon^ils 
(lijntonitii iiml ]>iv>|>riii!i hitlUiois iiiiil ihi< itcmiifii.t li-rtiiiN which iirii^c froai tltc 
narrow nntrri'ir or flrjnir »ur/rt(v, ami flex the ankle ou continuiii^ llicir |triinan,- 
■<4iuti. TIic i-xtrmitl xurfiiff twi»t.-< liackwanl iii the h>wer fnurth U> hi-fuine coi>- 
tiniioiii^ with tin- jUK-itcriiir .^iirfiim- of tho Dmlleoluii. The autrro'inlrrruil tw tnler- 
(ViUXfjiM fci>n/<r{Kig. lUS) is duse to ihe aiit«ro-cxierua) hortler al>ov<-, hut ilivcrjtee 
froni it below, where, an inch or more ubove the ntallenluti, it end* ut tJK- aix-x of 
tin- rough lriiin);i)lur area, which gives attadiiueiit to the iiiferiiii- iiilerwwoitK 
li^':inti-nl. Thi* iKinler uffoitlfi ntbicliiiu'iil to the interoMiteoii!^ mfmlmtiie, winch 
w'luirati^^ tin- nuiM-les ariciiip fi-oni thf antonor surface fnun the tihiiilis [iiKiterior, 
uliicli MU|>inale.4 llie ankle anil arises Imm the fusiforn) inienuil or xiiptunt'tr xnr- 
j'liGf. Tlie btier snriace oociipies the tioper two-think only of the Miiiih It in 
seinrated from the jweterior >t»irface by tlii? poKfrro-hilrrmil bonder, whi<-h j<«n.i the 
imerat-teoUB border in th« lower third, Jind (jives attachment in the nrnx-r Iwo- 
Uiirrla to a HhnHifi septum, the ilixp Ivantii-a-g'! J<i»<^'ui, sejiarjitinp the mnwli-s whieh 
I arise from tite i^urttici-d on cither wiilc. The j/iinffrif>r or rxtennw /ntrfacf, iMH'oni- 
ing mon- intemal below, f;ivcs origin tt> the soit-n" al»ovc and the ijexor longitH 
Jiallucis below. The Utter mmivUi< an- separated from the pcronei by a septum 



lLll1t«M •0A9U 



KrmiHki. aaiuiii 




Tiai* 






iBTl-BT, tOMUr 



FIBULA 



Pin. Wk— UoTlioinBl tcMloii of tbolMiDca (if [hulruM Uie Junction or tlHUpbFr And nUdk tbini). ihow- 
t llielt tfORtcD and •urfftou aad the ttlalluiin i>r Ilif Inti-rMuuauii uviialiraiu. (T^utut.) 

UtJtched (o the promiiK-nt poslrro-cxlerHal bortlrr. Thiit lionler \ni*iie» from the 
lyhiid priK-e;** to the Iwek of the niallcoliix. Tlie tiutriml funtmni, ilirwii-d 
liiwnwiinl, i> Mt^n in tlie middle lliinl ■>(' the |io:<terti>r snrfaee. 

The hejtd, the outer nurlin-e of the ninlleoioK, mid the triniignlar area above it 
ire kuIx-iiIhih'Oiw ; otherwiw the :>h.ifi in eoveri'd by niii-M-le^. When fracture 
DceufR, it is very eomnionly an inch or two abovi- the malleolibi. 

Oastficaiion. — The lower cpi|>liy:<i.'<, although it ossifies lii>it, joins the shaft 
about tne twentieth op twentv-tirsi year, while the upper epiphysis renmins sepa- 
rate until the twenty-secon<"l to the twenty-fourth y«>r. Tl'*' human fibnla is 
vestigial, especially its upjier end, whieh aeeounts for the fact that this eml not 
lily oeeiGett lost, but also unites with the shall last. 



THE BONES OP THE FOOT. 

The skeletiin I'f the foot is conii>o«H(l of (lirrc groups of bone*^ — tho»* of tlie 

tnru* (" the flat of the font"), tnrfntairniii' ("beyond the tami>f "), nnd di;/ih. The 

pbone* of the foot, at (hough resembling those of the iinnd.nre mwlified in (hediiM-T- 

lion of grater firmness, ami are in a iMinilion of permanent pronation and dormi 

Hex ion. 



IfiS 



THE BONES. 



THE TARSAL BONES. 

Till' fnrmin cnntnirn seven liom-.- — iln- ii.iira^ilii:<, culcancum, cirf 
or inivk'nliir, ami ilic tUrev t-imeirorni UiufB. 



iT^niphoid 



ORoovi ton »L(«, 

lOHC. Hill.. 




"■■STie*' 



tfin. Ilh!.— KIkIH utnumlut. un-lcr 
lUrlACC. (<ip&IICDolK.| 



I 



» 



The AstraKaltis. 

Till' atim'jahu ("a die"), or IhImi (Figs. 1%. 13«, 202, 20^1). ocfitpiw the 

ii|»]>er ptirt ul' iticnnlinr liio fWt, wlun' it urtirii- 
luti'!^ with till' ttliin aiiovc mill iiitt-Mi:illv, iiiiil witli 
ill*' fil>ul:i >-xt(-ri)ullv. Ii n-i'i-ivi-s tin- tv(.'t);lil of \\w 
btxlv fruiii i)i(- tibiu, nml irui).-'iiiit.'< ir livuriicnlittion 
to (lie uilt'itiii-iiiii Ih'Uiw ntiil llii- m-aiiliniil in t'mtit. 
It* lonjr axis is ilin-en-il forwiinl anil iiiwanl to iIh- 
convex anterior exiivmiiy, or hfwi, wlik-h in joined 
liy a Hiifrlillv lonnirieied mik to tlie niitin part, or 
li'iilif, lieliind. Tin- t'jijjei- tiurjt'rr \^ oceupied bv 
ttic tiiicldear ariioiilar fiirfiue for the liliia. This 
is eonvcx from before baekwiinl. and slitlilly cnn- 
eave iransverBelv. It is bi-oa<ler in fVont than 
l>ehind, and eoiitimioiis with the lateral fueets for 
the malleoli. The J'aeet on the oiiirr furfticf, for 
the external iiuiUeolii^, is triangular and vorticidly 
coneiive ; that on the hmrr mirfaer, for the intemiil 
malleolufi, is tniuUcr, narrow, and pyriforni. To 
the rough t^urfacc bvlow tlie in ten ml liiovt b 
attaehud tho deep pijrtion of the deltoid lignmenl. 
The iiiiflrr mirjiiir present:^ ii di-ep proove for the 
inlero-tseoiis ligiiment, which imi-ws from williin 
oliliijiiely ontwiinl und forward to tho neck, and nojninites llie two fiieetx whieli 
articniaii' with llii- ealcjineinn. Thi- |Ht?ilerior facet is eom-uve from bihiml (iir- 
wan! ; the stnierior i* eonvcx and n-stn upon tho f!ie<'t on the snNlentiienlnni tali 
i>f the OS ealcin. The anterior facet is eontitnioiis in front with the oviil fiieel uii 
the head, for the Hejiphoid, though llicre intervene? bi-lwein dieni inlernully a 
small facet which re>ls ii|Min ihe inferior cjileanio-MiipIiiiiii Upiinient. The y^oJi- 
trr'/or lurjarr U a mere iiiirniw border, frroovi'il intirnidiy for the flexor )oiigu.<< 
luillnciN. The fufn-rcte bonmlin^ thi^ yrciove externully gives altaehment to the 
posterior Ijand of the external lateral ligiunent of the ankle, and is sotnelimes 
found ue a i-eparate bone, the 'm tryiiniim {" triangular Imhic "), 

The Calcaneum. 

The <yiilennr<im f " lucl ") or os calfin ( Figs. 1 1*7-202), the hirge«t hone of tdo 
fool, projctrLs Imekward anil downwsird to form the heel, whieli iicis its a fulernm 
for the calf-inusi-leM. It transniits most of the weight of the hodv to tlie ground. 
lis long axis '\h directed forwanl and » little oiitwun) from its enlarged ]M»I«ri4*r 
extremity. 

The upper mirfai-r presents in its fore pari, two facets ftir nrlieulalion with the 
EKinigalnti. The larger, iio'steriiir, mid external fiic-et i.* convex from before hack- 
wanl ; the nnlcHor om- ii^ long, eoiieiive and ofieii MilHlividwl. It is loeateil on 
the upiKT ^nrfiwe of the niMndmrnhtm la/i ('* support of the antragallls "), a flat, 
»hi.df>iike process prajei>ting inwnni on a level with the iip]>er surfaee. Between 
these two facets is a groove for ihe infernsseons ligament, passing obli()iiely for- 
wanl and ontwan) to a rough area on the fore part of the upper surface, where the 
extensor hreviti digilonmi arises. The timler nurfii'-^ in narrow, rough, and trans- 
versely convex. Ii ends behind in two tubercles, which give atlachmcnt to plantar 
iitiMde& and the plantar Gisoia. The inner tubercle is the larger, the outer tlie 




TIIK TARSAL IIOXIX. 



169 



moiv pniniiinrnt. In fmnt nl" Oiiw rlic lotiif {ilnntnr lipimcnt i« ntiachcti, wIiiK* 
tJip -Ii'irt |t]»ti(nr lij^tmt-til is .ilUi<')i(-il I" lln- iintni.ir liil"-ivlc at llio IVire onil of 
tills riiHatx- luul l<i tlio hIiuIIuw ^nmi'^ in rititit. nf it. Tlii.' hmrr nitrfare i* runcavo 
brtwvrn tlii'^ |Kb>i(-ri<>r .■•urliioc tK'hind and the ^iixttrntiiciilnin t:ili iu front. Tho 
amler (iiirtii(»? of ilie Intler prv.-M.>nt'i a gmnve omitiniKutH witli iliiit a) tlic back of 
Uh- ui^tnigiiliL-' fur till- Bexor longiis lialluciit Icnilon. Tin- uiilrr uwr/Viw, ixiiigli, 
flnl, and iinlRiMiimi'ous presents at its fore jwirt two iMglit gmnvt-s. the iip|K.T for 
tin- tonilon <if tlw [>er"nfiis hrcvLs, tlic lower for Uialof the |>orc>iii'ii» tongns, fcpa- 
hiIihI liy a ridge or tiilxTcIc, thf pernnml tpiii*. TIm? juixlerior tnirj'uff t* t!ni<H>lli 
abu\*«, trbotv it is separaK'd by :i biinai fnim tho tendo ralcaiien^ (AcliillU), wliic-b 



uniewuia 
•unraci* 

TtCULUM 



•OKI ■■»«. 
OITKkOAUl* 



■ IRICVU" 

roit <u- 




tunrMC 



tUXFJLCE 

■Hiicfi lusenecc 
Pu. 19T.— RI()il cnlcaanuin. itiMriial mirtkce. litpaltcliolij 

ia attached to the IhwiT [Kirl nf iIiik isiirfiu-c. On tW nvierinr mr/atf 'i» » 8ndd1«- 
sJuimmI arlu-iibr fui'ct fur tin; i-nlioid. 

rlie miranciint nnd iKtrHgitlnn nm )mtli very viu<ciiliir. Tho vcin> of the 
former eniei^^ ino^ily on thr nini>r «id<\ wlieiv ihey an- k-s.-* vxpoMed to preasuiv. 

The Cuboid. 

The WW(i (" ciihc-lik.- ") ( Fijr*^ 198-202) lies on the outer side of the foot, 
between the rah'ani'iini lichind and the fourth aiul fifth metatar^^lH in froul. 
Although eiihoiiUil, the fniir Hiirfacee adjoining the external converge (o it, 
giving the bone a pynitiiiihil §ha]>e. J'onft-rintlt/, it artlciilates willi the ealca- 
ni-imi by a saihile-MliajR'r! facet prolonge<I backwani at the lower ami intcr- 
niil utigic, beneath the «ili-:iiieinn. Anfci'iorfii, a •nialh-r facet is flividcfl into 
in onlcr triangular anil iin icinir quadrilateisl purliuu for tiic fifth and fuiiith 
nietatari<ul bcnie*. rcsjH'crtively. Tho upptn- «urfnct, dirwU-cl wjinewhut oiilwunl, is 
flat andiion-arlimlnr. 'VUv hirrr mtr/ncf precents a protninoiit ridfp' or /i(6(rw((y, 
diri-ctixl oliliiptcly iiiwiinl ;tnd forward, in finnl of whicii w a dci.-p jrrtiove for lln- 
pi-n»nfu^ hmgui*. Tci the ridjii- and the trianguhir surface bihind it are utt:ieht»l 
the plantar liiianieiit-". On the narrow i\ftrnii%l kit/hi-/- or honh-r the oiHor end 
of th* ridg^! ou ihi^ lower T-nrfacc projci^li* as a tulK-rfle, whieh is ui^uniiy fneellwl 
for H .loitamoid hone in the tieiid of the jn-ronens lonfrus tendon. The inleruat 
mr/ace presentii nnaril^ middle and iipjier part ii fawt for the external enneifomi, 
ana oftentimes iM'hind thi-* a seenn<i faeel for the scaphoid, while the rest of the 
surface is rough for interos-seon- lijpimi'uts. 



The Scaphoid. 

The tieaphoid or mn-iVn/rti- (" biiiat>slia|NHl ") bmtr { FijT*. 198-203), Riloatcd on 
the inner fide of the foot betw<>eii tho a.-<tragnIa-< uml (he ctmcifomi bones, is com- 



170 



THE BOXEB, 



proiis^ from lieforc laipkward. Proximally ite rcrtn«vitv artirukt<>i) with 
litiid of the aMragaliiJ. Its convex dielal giirjucf. is Aiihiiiviiled into three tri- 
iingniar facoL-* fur ihe cuneiform bones. Above it i^ ron^li and i^nvex, Mon- more 
narrow and uuevoii, cxtemally rough for ligaments, witii an iiiconAlant &cct for 







or xiiLUi 



Fia. l»,— Tli« tmnn of Uic right fool. Tkucd rrom above. (Alblniu.) 

ihc enhoid. Inlfmnllif it is nrolonged downward and inward into tlie prominent 
mxiiihdid tu/jo-i)*Ui/, wnich gives InBertion to jiart nf the titjiali.i (lo^terior, and, 
being ftnlx-wtane'iiis, i.* an important landmark in finding the m«iiit-tjirsal {Cho- 

Eart h) joint, which U bonnded behind bv the aatiragaluti and oalcaiieitm, in front 
y the ficaphoid and cuboid. 



L 




THE TARSAL BOXES. 
The Gimeiform. 



171 



Th^ thrfe cuneiform hone*, nameal re^jnx; lively from their jmsition from williin 
outward, inttrnal, middU, and cjiemat, are ^ledge-almpcd, and lie bciwoen ihe 
scaplioid and the three inoer metataraal bones. Thi^i- proximal 8urf»ceH, artiou- 






rtMHcw* •MVia 



ptaOHtv* nuTiut 

on.) 



MrmMil awiTi 
{■■•■I 



tiT(H*ea 

LOHOU* eiarTOMI 

(•••■.1 




Eitmsaa hohhu* 

H*UUOIt tlNS.J 



tna uf auiinilar alturlimMiton xhv rlnrwl iiiir(iH<ii of the tH<nv*<>r Ihp knt. Whcrp the nre** 
i lowrtloii an bolli pmciitvil. tbcy arc Ln ii\c >aiDc col^ The thLnl ttonal liitchjaacou* hi noi 
• planiarlntcmuoiulTiHnii'n. ISH.-unuHlirfi. , 

itioff willi th« Mnptioid, are concave and in tlie same IranHverite line ; tlieir distal 
EtiHacc!', artioulalitig willi ilie three inner metatarsals, are cmnvex or tint, and the 
middle cuneiform Iwing the shonesl, a deep recess U formed, into which the base 
of the second metatarsal is received. 



tra 



THE nOXES. 



The Internal Cuneirorm. ^^^^^^^^^i 

Tlictni/TiMT/ cuneiform (Vipi. 1 its. iiK}, 203), i In- liirp;j.| iif tlic llirec, ha« the Iraw 
of tliv wi'iIfTi- ilitvcti'il <li»vii«jinl iin the iiiiii-r liiml<-r nf ilic iiHit. The distal, 
kulm^v-sliiiiK-il t:i<'i-i l'i>r tin- liiw of rhi- llor. nulaUiSitl U iiiucli lar|tcr than the 
|)n>xiiiml (lyrilonii (jkcI foe tin- -<it[ilnii<J. On tho intirtiiil Bnrtai--c if an olilit|Ue 
slinllrtw priMive for iln' tiliialis anicriDr ti'iidon, teadinjr to an oval facet antero- 
inffriorly where the tendon is in jiart atlachMl. t>n the i-ongh, concave exter- 
nal surface there is an L-Hhapeil facet along the ii|)ucr »n<) ixisterior bonlers. whidi 
arlicniates with the middle cnneifomi. and in front, where a dliitinrt facet i» 
marked off, with the inner side of the Wjjrv of the wcond nictatai^al hone. 

f The Middle Ctineiform. 

The ntiddU cuim/orm (Figfi, 1!IS~2()2), the •iinalle^ji of the three, hap its base 
directed iinward. Tlie facets in front and l>ehind are wedge-^-hajx^d. tliat in front 
for the second nietatnrs:d being -^lightlv smaller. On the inner snrfaee is an L- 
shajwd faeel along it-; iinjH'r and [Hislerior borders cor ret^ ponding to and artivu- 
laling with tlint on the uiternol eiineirorm. On the outer NuHaee a tact't utfHig 
its })osterior border iirticuhitc-i willi the exiornal ouneiform. 

F Tlw External Cuneiform. ' 

The extaiud ainelfonn fFigs, IIW— *2II2) also Uaa its bafic directed upwanl. 
C'-ontinuoiis with the triangular facet for the base of the third nictfltarKil an- small 
facets at the fort- jwrt of each lateral siirfaee. internally for the st-coni! mctritar- 
sal anil externally for the fonrth nietsitiirsal. The internal snriiiee ha* in athli- 
lion H facet nlmig it:- posteiior lnnclcr for the niid<!le entieiforin, and the cKtenial 
tfurfaou hois » larger faei-t l"'liiN<l :iinl jhove tor the cnhoid. 

[ The Metatarsal Bones. 

The five metatartat bones ^I'lg^. 1!<8-20:1) are nnnil>ere(l from within outward. 
They cli»sely resemble the metaeariwd lK)nes in having irregiihir enboidal b&seN, 
Brtieidating with the same number of boiiep as do the metfle«r|Mi! ; in having 
tajwring trianguhir j^liafts, slightly concave from end to end on tin- I>lant.^r aspect ; 
and in hiiving Intendly e<iniitrc«weii iiiad* with nrliiuliir lin-els extending onto the 
])IiUitar snrfiii-e.«, whi-iv they iin- gninvcd liir the flexor K iidc.ns. jiikI with tatenil 
tulicrcles unil dcprei'sloTis fiir the Intend ligiimiiit.-. The line of ihi-ir bases sIojh-s 
from within outward and backward, iiiul U interru|iird by tlic mortising of the 
second between the intenml and exteniiil ennciform bont-H. 

Tlie friU mrldliiriml, the stoutest and shoi-i<-Ht, Im- on itr< txiM: a Ini^, slightly 
oonenvc-, kidney -shaped facet for the internal enm-iform, ami nn inentmtant laeet 
externally for the second metatarsal. The lower part of the base projects down- 
wanl and slij|;htiy outward ;« the tiifjei-oHili/, whieh given Inf^-rtion to i>art of (he 
[>eroneus longus ext«TnaIly and of the tihialis anterior iuternallv. On the plantar 
snrfueo 9f the large fuaif are two deep (grooves for the sesamoid bones. 

The gr-rnml md(Uar«itt is the longest ; the others diminish in length to the fiflh. 
The Imiw of the "et-ond articulates in the morlLse with the three cuneiform bones, 
und extiTiialiy by two facvis with the third metatarsal, and occasionally internally 
with the lirsi. nirlnlnrMil. 

The 4<W' of the llilfl metntnnal articulates pruximully with the extenml cunei- 
fonn, internally by two faeetj« with tho second nietMr<Hl, and cxtcniully by a 
)iiiigle faoet with the fourth meiarsul. 

The Itaur of the faurlh mHnt'irmif nrtienl.ttes proxinmlly with the enhoid, 
internally with the thin! niet;itwrsal by a single fiiei't, and usniilly with the exter- 
nal cuneiform. Kxternally then.- iis u I'iiigle fa<i-t fur the lifth metjtrsid, Iwivlcml 
by a deep groove for liganienl^. 



I 

4 




TBE PlIALAXGES. 



173 



Tlie Ittuf of iliR fijik mdaifu-nfd articulates proxmuilly with tlii' cuboHl, intt^r- 
nally wild iIh- foiirtii mt.-tatarEa1. Oii its outer »«[x.-ct it pmjortj* as a lai^ miijih 
/ii/h-iimiVv uiion u'liich the tcutlou uf |)h- penmciti; brrvi^^ >ii inir?rtp<I. Being titib- 
Jianeous, it va aa iai|H>rIaJit kiuduuirk on the otitvr bunk-r of tliv fool. 



■ HMCII TUHHOU 



CALCAHCua 



GKOovt roa 
tnontu* voHftua 



tKTcnnaL 

CUM CI re mil 
■i&oic 

CUMIirOBM 

ewNiiroRM 




rmar acTATikatiii' 



• IIAHOIO' 

■enc* 



■mar rHSun< 
or HakLwi 



Fig. an^Tlir hunat of Itiu tlclit luui. vlcwol IVoin kclow. rSpallvholiJ 

THE PHALANGES. 

^iphaiangtB (Figs, li)!)-204) rescniMo bo ilo§dy thof^ of \\w finirrn; tlint 
only tlic fiifTerenecfl neeA \k- notietni. Those of the great toe arc larj^T tluin those 
of tlie tJiiimb, while those of the other tocJi art^ much einnller lh»n thoi>e of the 




174 



THE JiOXJSS. 



corres ponding lingers. Tlip sliiiftii of llii- phiiluitgi'? of llic /ir«f. row-, in tlti- four 
tiinnller f«e», are narroweil in IIk* ii)i<l<llc, biiiig (■(unprt'sNi'iJ Intrrully. In tlic 
Kumv tocM the |>hal«Dgci) of llic tKcmul row nrv very idiort nnd !>timtL-<), e-iwciullj 



lon.i 






AaeUCTOR »IB 
FLUOR ■KIVU 



ricioR aitcvim, 

ttmo itooucTonTHjiaia-- 

VIII«UBH«kLUeil (ihO 



M*Li.ue>a Una.) 




ntiA* aaivia 
oioiTsatiH (on.) 

kaoucToa niiNtitl 

DiQiTi (oa,) 



rLCXoa iccnvoaiua 
(tut.) 



rvKoa aatvia HULLueia 
ion.) 



rttxan bkevis 
«iK<Hi ciaiTi ion,} 



•oouoToa «aUMlm 
HkLuicia (ON.) 



naiiLia cNTiitioN 
una.) 






■■DUCTOa «ND FLEMM 

latVIS H1NIMI OiaiTI IIML) 



rLiioa aicvia 
eioiToauH (int.) 



riiio* LONSua 
cioiToauH '■■a.) 



rLCioa aatvia 
OiaitOMUN ilHs>) 

FN. 1D1.— Arcu of muKuUr BtUrtimcDt an Itu ijImiUr diirfaco Of Um Iwm of IliB torn. Whara tlw arcai 
Of Oltgln a^'t InMrtltin Hrv hiilli iiciwnivl, IliKT an- In lh« UKDC Culor, OU. 'iirlctiL [NH. — UiKrtloiL Tlur 
InWlUoii of Uir amind and tlili4 vrailoiu of tin rtexm brcili dliUarum are not iKbclM. 

th«w ijf till? foiirtli and fifth toes, which are not iufrw^uently ankylosed with the 
tcrmiiHiI pli.l1 a i)gv», 

The (wo Ar»ijttoiil hnnm \n the tptidnii of the llfXi>r brt'vis hnlliipi» gliili- in 
the two gnmvos on the pluiiliir ii»(H-ct nf the heiiil of ihe fir»t luetutaroi bone. 
Hesanioid boiicA <)eaii<i(>iiullv iK^eiir elsowhiTc in the ((Mjt. 



THE FOOT AS A M'HOLK. 



176 



Ofwifiralion. — Tliv iiivUiCarsiit »iul [>litiliingi:sil Uoiics verify exactly I'lkv (lii; 
I cnrre!i]K»)(litig Ih>iic« in the hniK). 



THE FOOT AS A WHOLE (Kip.. 199-204). 

The fiBrt is iiarrowpft nl the liwl ami widens lu tin- IicikI^ of tl» metutarRil 
bou(.v». Tlw Ixtncs of ttm fiwt ii>rni ii limytlmUnnl ttirh wilJi n single pier, Uii- c«l- 
«ai»truni, hehinil, wliilp \\w forvmrti jitcr \* ronii«(l by (lie li«»il« of ihc nH-tutiir- 
Mi) txim'n. It inuy In' tiividi-il loti|ritii<liim1ly into two luirts in front, with u <.t«n- 
mou !<up]>on hcliimi. Tho iniior iiivi.-ii)i) c^unsifbi of iJii' ponteHor (wo-UiinU of 
th« tsdcaiieiini ami th<- n.ttrHgii]iiT>, ^tcajthoid, i,nini>ifor[n.«, aiiu the tlii«e iiiiier iii<;ta< 



fisTMoAtu 



r^^^. 






7l0- an,— Thr bcinm nt tb* rithi fiv>t. tIpwmI Iroin tbc outer Mf. (Tntul.) 

tnr8ali<. It bcaiK the ^roater part of i\w weight, niifl 13 more nu84<d from tlic 
grrHiiMl ami more siirin^- than the outer areh. The outer diA-ii^ion is forraed by 
thv c:nU>niH-iiin, I>c9ring the cuboid ami the two outer nii'tatantalR, ami actri mainly 
«• a buttress to the inner avf\\. The lon^itndtnal aivh i* i^iipportej largely by 
the phintar 1i(^meii(^. The Irantvfrnf arch, having its two internal piern at the 
intenuil vuiKitomi and the first nietatarsil, and itf extenial piers at the cuboid 



.-C-' 



/>£<: 



Fin-SD*.— The lx>n« of ihrrliht font. vltwsdlVoiDttic Inner *lil«. (Sfallcbola) 

the fifth inrlatumal, b* forn]*d by tho wedge-ehape of thu <:iin«iform boncji 
'antl of the bjiwii nl' the metalarsalt!. 

Thf hwij-tlndiiial arch is wwikest lwlwM*n the astniftalHS and scaphoid, wht-re 
it iy liable to vieM, f;'^''»g rise to flat-foot. In this condition it is well seen that 
the aix-h h not i|iiit« straight fnjm Ih.- heel to the ti«:!<, lint is silijrlitly convex 
, intenmllv and wtncave on the ontcr border. The aslrairnbi-i inclining inward 
and the adranenni ontward in front, the outer border of tlie upper surface of the 
former is found over the middle of tli.- latter. This m!ikf« the internal malhwlua 
appear more prominent, for the external mallcoluK lies i-ver the outwunlly pro- 



176 



THE BOXES. 



jttcting CAloaneiitn. 
tlia 



Tu infantry the head of ibo ai^tragnlus i^ iiiclin<^l iiiwa 
mure man in tht? adiili, and the foot is then naturally inverted. 

The tuberosity iif the scaphoid on the inner border of the foot and that of i)ie 
base of the fifth metatarsal on the outer bonier, holli reiidily felt through the -loft 
partfl, are the Iwst guides to the meilio-tuiT-al and ttn'ho-nielat:irwil juints, respec- 
tivelv. The tuberosily of the tiftti in«'t»tiir>uil U a fingorN brejulth in front of the 
medio-tarsiil joint, iind dtrwrtly in front of ihf tarBo-mctntHrsnl joint ; that of the 
•ieH|thoid '\f> two lin^^-rs' bivudlh behind tliv lui'M)-ni(.-tiilari'ul aud dinx;tly in frout 
of the mediu-tur^l joint. 



Homologies of the Bones of the Two Extremities. 

Tlie following uonelueion;! are p-nerally admitted ; The thomde and |>elvie 
limbs arc oonstnieted on the same ty|»e in (heir attaching; j;inlle« and their several 
segnieuts. In the pelvie and tihouMer jjirflles the iliiun eorre^jKHids to the M'a]iula 
and the itichiuui t<) the eonicotil |uyiit-«*. 

At an early *\u^m of cnibryoiiii- lift- (he limbs are folded vcntnilly upon liic 
body, and prewnt ])n'- and jKiHi-axial Iwrdi-r*. 'JTit- durMul or i-xk'nsor Mirfiiu^s 
nre cxtcrnnl an<l the v<-ntr]il or flexor siirttiei's are internal. lidtttT, the upjior 
limb rutalv^ onlwaiv! 45°, and tlie lnwi-r linil) colali-" innard flU". This brinp« 
the tiexor .Mirfaet' in the n]>i>er liitih forward and inward, and in the lower limb 
baekward. The Muall troeliaiiier and internal rtHidyle of ihc femur, lh<- tibia, 
and tJie gitsil hn- in tlie lower limb are pK-axial, and lorrc^pond re.M»wiively to 
the ereat tuberosity and outer eondyle ol the huineriiH, ihc nidius, and the thumb 
in the upper limb, etc. The patella in the lower limb and the olceranon in the 
upper have no corresponding |Kin>i in the other limb. 

The adult human skeleton is .adapted in every part to maintain with eaae the 
ereet attitude by luing nearly bsilaneeil around the line of the centi-e of gravity 
in the standinj; iKir^tnn-. .nnd in lhi?i rcsjHrt it lUfl'ers from thai, of other nianimats. 
Stability and strength arc jirovtded in thv lower litnb)^, mobility and lightncHS in 
the up]K;r. 



THE SKULL. 

The iHinc* nf the head, conijMwiiifi tin- skull, conlaiii and pmteel the bnitn and 
sense-oipin-s as well as the eonimeni-cmem of (hi- ulimeiitary ami respiratorv' 
tracts. With the e.veiption <>f the lower jaw. the bones ari' immovably joini-d 
together by sutiuvs, forniiug a bilatendly »ymnietrieal, spbi-roidni fij'un', some- 
what compressed hitcrally. Tlie skull is supportinl upon the verti-hnd column, 
with the up[>er segment of winch it articulates. Kor description, the Iwenlv-lvro 
bom's of llic wktdl sire divided into two si>ts. The cranium, or brain-ca»e, is the 
[xirt above and iK-ldnd. and ccinipri«'s eight bones— i-iz.: 
( Oceipitul, 

I Sphenoid. 
lies, ~' 

J wo tempt 

[ Kthnioid. 

The fruv i*< the lowor and fori^ part, eomi>oscd of jiix paint and two t-inglo 

boms, or fotirt<'en in all — viz. : in imir-, the inaxilla-, palate, inferior turbiitatv. 

nasfll, lachrymal, and malar ; single bom-s, ihi- vomer mid mandibic. The liynd 

bone may also lie classed here, a.s apiiendieular to Ihe liones iif (he bend. Th« 

base of the skull is preformed in cartdage, the roof and sides in membrane. 



Ilasilar bom 



ipunib^ 



n e I f Two iMirietals. 

Roofbonw,|j..^^^j 



TUE OCCIPITAL BONE. 



177 



THE BONES OF THE CRANIUM. 

THE OCCIPITAL BONE. 

This I<UM-i)^:(^!<ttap<il himi- tl-'igs. 2(j4 iiihI 20-') ) i'urtiw the tuaok niid n jxirt of 
Uie Iwse of the hkull. Its long tliami^tcr is dirt't-utd fmin boliiiu! dnwiiunnl and 
f .rwanl. It ciiiinistii of lour larin, whifh mei't uruiin*! the /ot-omoi nHUfnnm. 
1\\i-re [uirlM arp dii^tiiii't at birth, and art' r(ri>rf:*<'in<.-d bv »eparnu- hawf iii"low<T 
vortt-bnitcs. Of the»>c parts, lfi« broad, flat, curvi-il {xirtioD bdiiiid tin- fomtncii 
mitciitim, called the »jtumi.o-occipUaf, couBJats of two juirte. Tlie U|i|)i'r triangu- 
lar !«f!Tnpiit lying above the bi^hcet curved line re]m-j*ciiU the htlerpariiiat /«i«e 
of h>w*T vorteb rail's, and ic »oi»rtitiiea separate in own. The two exocchiitaf/i or 
<»ndiflur pwtium lie one on eilhcr j^idc of the foramen mogiiuiu, uiid include the 







(■now in ■KiiniOM 

CONI»Vl4ia r9IUUCH. 



Tib. 9M.— Th« ooolplUI tmii'. vii'wt«l tnna Iwlnw, IBiBilWhrpltl 

eondyles and jugular prowKsc*. They join the !«[iianM)-(K;ciiiitaI Ix-hind and the 
kafi-oocipitaf or ho'ilni' itmcrnii in fnint, Tlii* lattt-r i-xtrnos forwunl from the 
fnninicn to thi- ii]itn'niii(l l>one. Tbo entire bon<' is tliitt<ai«cl and mitdi curved, and 
pff^TK-nti^ » voncave wrcbnil siirfaci- and a <'onvex external fwirface. 

The extemal nuDace i.i convex, and look» downward and backward behind, 
dowMWRni and forward in front. It jiresent* behind, about the centre of the 
iU)unmotL-< |K>rtion, a well-marked pi-omiiience, the rj^lcrntit oecipUai proluhtranee — 
an ini|>oriant landmark to he felt ihrouKh the wealp. From tW a median ridge, 
the external on-ipital ntr,!. lead-* to the back of the fur.nnen niapium. The pro- 
taberance and cre^^t give nttaehnient to llie ligamcnliim nnehie. A traOBVerse 
ridge extends laterally on eaeh side fnmi the exteninl (K-cipilal protubiranee ealletl 
the ^wper/or ciintw/ /w (or middle nuehal line). It arelnw outward toward the 
laterafangle, and gives origin to the trapezius intornidly, an<l imrt" i-f the ooei|M- 
talis, sterno-cleido-maatoiil, and i^pleniiw «i]iiti!« externiiUy. .Almve this line U 
sometimes to Ih- »xn a fainter riflp-, the hlijlirst t-urml Hue (linea .-'Upivnia or mijio- 
rior nuehiil line). Thi» is mon^ curved, nio.«l niiirked nie^iinlly, and extend.^ lat^I^ 
nlly townnl the Intend angle, enelnsinj: with tliesujierior curved linea»in<Hiib,dense^ 
semilunar area. Tliis iiu<^ 'm^ often aliment, but when prc.'^ent give^ aitaehmeni to 
the epicranial iimneuru^tiA and a few fibres of the oceipitslil^. The surface almve 
thi;* line is evenly convex. The rouph surface between the superior cnrved line 
and the foramen ma{;nun) is divided into two rough areus on each tiide by the 
iaffrior cnrv-d (or nuch:il) Hue, wliieh curves oiitwani and then downward from near 
tile middle of the crest to the jugtdar process. The s]>ace above the inferior [iuo 
II 



178 



THE BOXES. 



N 



receivfiA die cwinpk-xtik mcsiiilly. Tlic lowi-r ^jiace U oociipiwl bv tho revti (-upttis 
posteriores major and minor and the obliquus superior. On the erfemal or uu<ler 
«im;;«« of tht eontl filar poiHont wv see the eoiidi/ldt, whicli lie at the sides of the 
atucrior liair of tlu' furamcn niRj^iiiim. Tiirmigh thciii die head m-U upon and 
artivulaU-s with tin- Vtiiim. Thi-ir ^moutli, ellipticai, eonvex j^urfaw*, eaitJIapt- 
olad in tin.' n-wiil I'liito, coiivfrii"- in tVimt iiinl Uiok downward and outwanl. On 
till- niitiiiin !"idi' of K-ac}i U a viyug\i impratiiim or fitbervk i\tv iln- lutvnd udonlntd 
or check -li^m en til. B(-hiti<l each condvlc is a depression, ilie itrmtrcior eondiflar 
fotm, wliich receives the hind edge of the articular facet of ihe ailaii iii extension 
of the head. At the bottom of the depression is stmietimes aeeu the external 
opeuing of the posterior eondj/lar foramen, for the pactsage of a vein from tlie 
lateral sinus. It is sometimes absent on one or both sides. The base of ilie 
condyle is traversed by the mitr-rior condi/lur Joraiiu'ii, wliich passes outwaril and 
forwanl from the cnuiiiim above the fommeu magnum, and tran^-mits tlie hvjto- 
frlo^^id nerve. External tu each condyle the jKyii/rrc (from ./"y"'"'"! " throat ") 
priin-iw presents an inferior rough surface, which lies al>ovt' the tmnsven-c process 
of tlie utbiK, and i!;Wv» insertion to the rectus capitis latemlis. T/ir in/mnr mir- 
fun^ of iJu- /inKi/ar portj'in in iiu-Wintl upward, is narrower in front tliiin tx'liiiid, 
and i* Iraiisversely ctmvex. It presents a sni;dl nx'diini iiluiripif/i'iit lubcrrUy 
to wliic'h is atLiehed a priHicw* iVom flic fibruiis apmu'iinisis ut ibc pbarvnx. On 
either side of this il is rouf;h for llit; rit'U en]iitis nuliriori's, in.ijor nod minor. A 
port of this surface ewn be |ia]|Lited, thimgli nm easily, thnrnigh the tnouili. 

On the internal or cerebr&l surface the m/tnitiiuux (" scaly ' t jiorlion iireseuls n 
concave surfa<:e divided by a transverse and a longiliidinal ridge into four f(lssl^, 
the two superior for the occipital cerebral lubes and ihe two interior for ibe cenv 
bcllar hemispherra, Tlie intersection of these ridges in marked bv the internal 
oi-riiiiinl protabfraiiiyc. The longitllduial ri<Ige ab<jve the protiibt^auce exten<Is 
to the superior angle, and is grooved for the superior Inngiludlnal dnus, to the 
edges uf which the falx cerebri is attached. The tninsverse ridges extend to the 
latend angles and are similarly grooved for the lateral sinuses. The tenioriuni 
ccnrlielli is attached to the edges of the groove. The grotrte fnr the longitudinal 
»inus pusses to otic side, usually iho right, of the uitcnud occipital pr<niibeinnce, 
where ihc gn)ovc is deeper and lodges the torrulnr llfn'jiliUi (" winc-prew- of 
Heropliiliis"), The sharp vertical ridge below the protnbcnmoe, called the inter' 
»«i/ aevipiUd crtmt, gives attachment to the falx etix-belli. It paxws to (he fonimcn 
magnum and sprewU out into its margin. On the nppi-r Mtrfaee of the jiiipihr 
jirorcH is seen a dccpgrmivc leading to a iioteb, flu- '/ut/ii/ur imtrfi, uii the anterior 
bordiT of the jugular pniccss. This imteh with a similar <iiie on the [(cirons |u>r- 
tion of the temiMiral bmn* fcirms the jiii/ii/itr /vniuirii (f"i'anieii lacerum i>o>leriMs). 
The gnxive lodges jHirt uf the sigmoid or Icnniual porrion of the lateral sinus. 
Separating this groove from the fomimn magnmn is the /i((/i(/«j' (■nitnciict, wiili 
the intraeraiiial opt'ning of the anterior condylar foramen miemally, and that of 
the posterior condylar foramen externally (on tlie side of the groove). The npiser 
surface of the himilar nroermi presents a central groove, the haitlUir ^oorr, slanting 
iijiwani ami forward for the oblongata. On either margin of this surface ie half 
of the groove for the inferior petrosal sinus. 

Angles. — The auperior antjie, as well as tlie two lalenil, belong to the squamous 
portion. It Bts into the angle formed by the meeting of the posterior superior 
angles of the parietal bones, and corresponds to the posterior fontanelle in the 
frettL-s. The lateral angle* !»t the outer ends of the stiperior curved lines occupy 
the anglc;^ between the parietal bone and the mtistoi<I |K>rtion of the temporal on 
eitlier side. The anterior or inferior iinffle. is repn-sentiil by the oblong, anterior 
surfiiwe of the basilar portioD, united to the bisly of the sphenoid by cartihigc 
until the age of twenty years, afterward by bone. 

Bordsn. — The (wo miperior tordem extend between the superior and lateral 
angles, and are convex and deeply serrated. Thev articulate with the posterior 
bnrden; of the parietals, and form the Inmhdoid (" lambda-like "} or parieto-oee^ 




THE OCCIPITAL ftOXE. 



179 



pital KHtitrr, Tiic Ivo in/rrior hmilrri' extend lit-tweeD the lateral and nntcnj- 
infcriur angles and ftre uneven ami less d reply (Serrated. Between iJie latent) 
aogU^ uihI <)m- jugulHt- [>F(>cesses they artiruliilc with the ma.'<toid iKUlions ot' the 
t«m|H>nilK in iho iM'rifiito-maMaid mihire. The teniall roiif^h extroniily of eaeh 
jiignlnr itnH-ejw artioiiUies with the jn^ulur (iiwt ot the pclrouti ]K>rtion of the 
teniporaf lione hy nvnehimdronis uiiiil about the twenty-dflh yrar, when the union 
l>econies oe*seniL4. In fniut of the ju|;iilar proee^ \« (Ik* )-iuuoth juj^lar notch (Bee 
tibtA'f). |{4-lwiH'n thi^ notch anil (he a ntcro- inferior anj;le the borden- are roup h 
tor artii-iiljitiuri with the (R'trun*^ pr)rti<>n of the temiKiml lionc. A i-citnewliat 
orlapmal tiinn \.^ not iiifrt'fjiiently jirtHented by thte l>one. due to the projection 
of (tie juipilar proee-iseH and the middle of the »-uiierior Iwrders. 

Thv Joramen matptum is oval in vhaiv. with the kiri;^ axle direeted from before 
baekward. It la eneroriehed H|K>n laterally in itj§ fore jinrt by ihi' condylei^, und 
transniitit the upper end of the xpinal eowl with it:" nKniliranei" ami nceoniptrnv- 
it^g ^dTH-tores. From the eondyle". thi<'lt ridp-x of l»i)ne, whieh sln-nj^hen the 
skull and traD>^miC itj> weight 1u ihe amtly !<->, pasn in four din-etionii — viz., for- 




tuavuH 

JUaULJLIt ■<OTCH 

■ now IN *HI(- 

AI01< CO NOV- 



Fm. M.— Tbe occlptlAl bunc. Tlcwcd I>«m kborc, {Sfultdioli.) 

wwxl into the liA.tilar prtH-cM, lalemny inlo the jiipiihir prooii^^s, huokward 
amuiKl the foramen, and ihenee iipwanl hk the oeripiml eretit, etc. 

Dn-dojimfiii. — The ba.'^ilar and condylar |»ortions 0!*Hify *«eh from a single 
eentre. Tlte squamouH portion has four centres in two laterally disposed [min' — 
a pair above in the interparietal portion, and a pair hclow in th<^ |iupmoeci|>ilal 
portion. These two pain- usually unite, Imt may renuiin wparate through life, 
forniinn un iiitequirietul Ixinciw in h>wer vertebrates ; or, nion? eomnionly, two 
lateral li«9fiire« reiuiiin,a condition n(>ually found iit birth. The condylar portions 
join the w|uainoiu in lines extending ontwanl from the po)<tenor margin of the 
foramen nuignnm, and ihev join the bii^iliir jwrtion in lines paw^inp through the 
anterior cxtninitie^ of the eondylei^. The centres for the inteqranelal portion 
an depo'rite'l in niemhranes, those for the rest of the bone in eartilape. 

\'iirirtif'i. — There is enmetinies seen a groove for the oeeipital f'lmw along th« 
internal occipital cn-st. The (iigular notch is oftt-n found partly subdiviilHl by a 
small intntjuffu/'tr pmcav. and il is frequently sepMratrd from the gn»ovi' for llic 
(inus by a lliin tr!in''ver»e ridge. A pnij^i-tiou w>nietinn» fuiind beneath tbi' 
ju^uhir proe^-xs, the piinimrintoul jyrniviui oi' nmny manimuU, »kny rarely l>e so 



160 



THE BONE3. 



long u» to meet the transvtTse process of the atlas. Fretiuently the anterior con- 
dylar foramen is siilicllvided by a thiu bony spicule. Karely the l>8.4ilar pnx^-^ 
at the margin of the foramen articiilalts witli (he odontoid process, A mtidiait 
mcnibninotii^ space from the fonuneii mapiiim backward tu the middle of the. 
Eiipruorcipitiil is of int*'rest, because in rurc caws, when not ossifie<I, it may allow 
hernia of the bniin mid its iiii'iid>r!ii)es. 

AiiicHf'ilioii». — By ."•niurc:* the iK^cijMlal l)0»c is coniK-t^ted with the two parie- 
tala, the two lempornl.-i, and the sphenoid, and by the uondyles it articiilutvs with 
the atla^i. 

THE PARIETAL BONE. 

The parietal ("wall") fton-M (Fij?*. '2uG, 207) art- two syniraetricnl, qnadri- 
latend plait's which form a lai^- part of tin- vault anil sides of tiie skull, and are 
inter[)os€^l bctwti-n llw fn>nlu! and ihe iHtiMpital bone>. 

The external Bur&ce is t^invex, Uie eonvexity l>eii)g greatest a little below and 
behind the rent n-, at ihi- iiarUlat eminence, moat niarkci) in young bnnes. Arching 
acniss ttie bone jost below this are the tuperior and iiifei-ior trinpuriit ridgf. the 
bone between winch is smoother than elsewhere. The lower ridge, belter murkvd 




Tn. SOS,— Tba rJK'it |iarlL-u] l»iif., ciiI«t *iir(k««>. (TiOftnlMiiat.) 

and more constant, limits the tennwral ftwsi and the attachment of the ti'iniKiral 
muscle. Tho uyiirr riiUje, when present, gives attachment to the teniiMiml fjuM-iit. 
The surface alune it is eov<^rc<I by the sejilp. Xot 1)ir from the hind end of tlie 
npp^T bortler is the stnuU pnrlHnl JuntMrn- when present. 

The Internal surface is eoneave, and inarkeil by shulloiv depressions and ridges 
for the een;bnil cinivhititnis, and hv narmw t;rimvi-s fur brnnehes of the middle 
meningeal artery, uliicli rnn n|>wunl and backward from below. The largest of 
these runs from tin- jirojeeting ii/ilrriar iiifrrior anfflr, often as a eanal, for a short 
distanw, and is ii^et'ul in deurniining the rtide to which tlie Iwne l>eIougs. Along 
the superior l>order is a half-groove, eoniplctcd by the one on the opirasite bone, 
and lodging the guix-rior longitudinal sinus. 2icar this gnmve, in llie bom-s of 
adults, aud especially of the aged, small irregular depressions for the Pacehioiiiun 
iHslics arc iwcu, A nnall p!)rt of the groove for the lateral einus UEually erosSM 
the inner aspect of the jKiNterior inferior angle. 

Bordere. — 'I'bc «uf/n-!<)r, artlrrior, and po^crlnr bori-h-rx are dccjtiy scrrolid, iiikI 
thclader two, and ton Icsa extent the first, are alternately bevelktl at I he cxpensi' 
of the outer an*l inner suriiiei^, thus alternat*'ly overlapping and iK-ing overlapped 
by the adjacent linttes. The bone is thus im> strongly wedgi-d in as to |»revent dis- 




THE FROXTAL BOXE. 



181 



itiimuTHl to "ItT-ngthcn tin- onniii) vault. TliiMiii]»crior bonier form? with iliat 
»f llR'01»iJ*«»ilrl(ii:n- tin* *"7irt(i/(" arrow -likf"j#«^((r. Tlii-aDlvnor boixliTsof tlie 
two imrifinl Uxtt-s nrliviitute wiili 
tliv frOHlul l>Oiii' in l\\<tJroi\tO'iiari' 
Hitl m conmat (" crrtwn ") KiUure, 
ami mr^t the ttagiltal nntiire at 
in'arty a rijjtit angle in pjurowan 
skiilU, while the ixxilerior borders, 
which Tomi tlic UuiAdoiil nviure 
bv aniculatiun with \\w oecipital, 
nu!ct the ^^ittal «uturu at an ub- 
tnsoanelv. Tlieiw/>/-iorWrfrrha» 
Ihm- (livtKiontt. Bt^hinil, it is mt- 
ratptl for a short fUstam'c t'> artir- 
ulatc witli the miiAtoii) portion of 
tlir H-tn|»oniI bone iii the paritin- 
mti'liHtf Kithtrr-. \n front of tlii» 
the iRinl^T i* thin, eimi=tvc, and 
<rxleriuillv' bevelled an*) Hiiteil, 
when- it is oviirbipiMfl by the 
MjiiamoUM jHirtion of the temporal 
in the niiiuimoHn «ultii't\ The 
irn-ai wini; of (lie t<[>Iienoi<l over- 
laps the front ineh or so, forniii^ 
the tjiheiio-parielat suture. 

AagleB- — Of lh« superior unf^lc^ tJie anterior in Mt tJie l^rerpna ("i^indpiit"), 
tile [(osn-rior at the InriiMn (Gn-ck letter .(). The pmjeelinj; iiiitirior inlirior anjrle 
is at the ^j/cWoM ("wing"), and is nometinies exelutiiil from articulation with 
tile ^pliciii'id by tta- rontiiet nf the »ipi»ino-<iI iniil froriliil. 

OsslficattoD noeiint in uienibmiie frotn a )<iiigie i.-c-iitre mid commeDflee at the 
int« of th« parietal eminence. 

Vnrittieit. — Rarely a horiz^mlal itiitiire divides the bono into two parts. A 
large opening is very rarely ^en at the site of the parietal foramen. 




4HTlLc 

Via. SI}.~Xhu rfthi pailcul tionc. Innsr iiurlho«. (T**nil>) 



lion AnsLt 



THE FRONTAL BONE. 

The/roi»fci/("foreh«td"l tout- (Fi^t*. :i08-ai0) forms die skeleton of (be fore- 
bi-wl, aiid n«eivetj the frontal lobes of ibe brain in the eoncavily lietween the 
main or veriieal portioH, which arches iipw-ard and l)aekwar(l from the orbital 
margins, and the two thin horiitontal or orbltnl platen, whicb cxtfiid buekward t'roin 
the .tame jxiititii, sepcimted by a median gap, the rthnwi'ial noleli. 

The anterior or oxt«nial surC&ce is 'onvex, and most strongly no at the/rotttal 
fitiineiires, a liltle below the oentrx' of eai'b littentl half. Below an<l separated from 
these hv shallow grooves are the arehed /fupircilutiy ("above the laslics") W</i/f*, 
«>nverginji in tlw moliiin line to the wimtl cHiifWTKr, lielow whieb is tlic smooth 
(flaMiu (" little ifniootb plaw "). Trne(;» of the mrtojtk (" frontal ")imturf. which 
orieiiinlly sejiamted the two hiilvc^ of ill*; fnnitnl, iisiinlly pen-ist in the glaWlla. 
iMiiml the Mim-n-iliary ridge* lie llie fruutnl fln'Ufr^. wbieh eaiise the pn>miitence 
of the ridges in the male. The iirehcd *»y*ftii>r/«'(((/ (" above the orbit") riW(/«, 
more sharply marked t^xtorimlly, limit ihis >i)i'tliee below and foriii tin* aiitenor 
margin of the orbiliil rv>of». .Vt about tb« jniii'tion of their iiin<-r and middle 
thiril» is llie nupntorhUnl nolrii, Koraetinie.i a foramen, for lb<' Kuproorbital nerve 
ami urUTV. Tlie .tnpruorbital an-li en(U in two downward proji'e(ioii."i, the rjit-mai 
ami int/TJutl aMf/K/'ir /jrutvvwrji, of which (be external i.i a Birontrly p«ijei*tiiig laud- 
uiark, wbit'h arlienlaic.'< with the miliar bone, while the inteninl i'' .«liglilly marked 
and articulates with the lachrymal Iwnie. From the external angular process the 
temporal creti arches upward and Imokward, continuous with tlie lenijHira! ridges 




182 "^^^^^ THE noA'ES, 

It srpi»ra(<:*i the fi-oti(»l portion of tine siirfaco from 
I* mnl Iji'liitiil it, " " 
and givo oriji^iii to tliv tcui)Kinil miiM-ic 



on the iiiirictal bone. 

lomponil portion, bi-lovv iind Iji'liitiil it, wliiuli iortiis ]Hirt of the ti'tn{x)nil ft 




TIH*On*L CMNT 






■ ■0<k< 
M>OCt»» 

Flo. SOS.— The frmiul bone. Men ftom In trttnt. (Tolul.) 

The Inferior surface oonsijitfi of ttte orbitul i-itrfiicii's of t\K trinitgular orbital 
phU", wliicli form thcgreutcr piirt of the nxif of the orbits. Thoir inner niarpins 
Bfe )inmllel ; the outer piiss biiekwiinl iiml inwitrd, Clo.-^- Ix-hind the uut^-r part 







iHTCKH'i aHauum 

»NOCCI* 
HAiaL BI>INC 

Tm. »».— Th* IVontBl Ikih', tt«n IVini Imlilml. (?p*lt«hn1i.) 

of the itiipniorbital riiiRc thi« Mirfiu-o pnwentji the hcJirymaf fowa lodging thff 
Inelirvmul gliind ; iiiul bciiintl the inner end of the rid^' tlien- 10 n rloprejuion, tlie 
triH-lih-iir fuMMi (more nirely n tuhen-lc), for the piillev of llio Rnperior oblique 
niiLHcli^ of the orbit. I^'lwpi-n ami in front ni' the iiitcnml anguhir proeeswcs ia 
the M(i*fiV noieA. Ttits i.* ImiinJei! iibove by a nemilinmr, serniK-d .tiirfaee, which 
artictllat4^!4 with the upper ends of the nasal liones mesially and the iiaKal proeesses 
of the superior ninxilW laterally. It is bounded behind by u r<)Ugh, nearly 
vcrti«il fturGwe, the jiHsti/ procegg (Honle), which projects down behiiid, ^^upporte 
tnd articulates «ith tho posterior aspect of tlie upper ends of the nattal and maxil- 



THE FliOXTAL BONE. 



183 



jry bonc:*, wliiirti fiinii IIr* bridfp- nf the nw*-. From the (wntre of the nasiil 
pr<K-i-T\.t iJit- MUHil *fiinr imyrrts iliiwiiwiinl iiwl f^rwan! JUt a f^har]) |>roci;'>*. iiml 
beiM'tX'ii tbt' ciVHln of llic iiuiuii lioiit--'* nil'l tho vcrlicjil |>Uli- of ihr ■■llitiioid fornix 
u jiari xf i\tc Mfptiiiii of tito ikim!. TIm* »)>iiMt <itiii))i(-iiiv?' Ih-IiiiiiI the iiaMil jiixircii)^ 
u« a DiLtlian nil^, on 4^it)H•^ :>i(ltt of which ii> it nui'mw gnx^X't- forniiii^ h miiuiII 
pcirt r.f thp nx)f of tht- nasal fussie. KotWM-n the hiii-k of iln-«- gniovi-w iiiiil ihc 
liilprn»l un^lar pniocs- n"ti<'c the o)K^uiii|:^ nf (hi- tnn fntHlut Hium-'v, uhk-h lie 
lii-UvwH tlH>iiiiurriiii(l iiiniT tal>lr-i>f ihc Imne. ThoMitiiws lii- Ih liiml (hi- Miju-r- 
*'ilt;iry mljtes, fxcfinl a variahlo tlisiiim-e uvei" tin- orliits, aitd iirt- m-mi-.iHiI from 
tmr unothvr bv ii (hiu vortioal jKirtittoi), ii.iiiall\ dUpIiirtHl lo llie lert. lb-hind 
them' o|H>niii)^, urwl belivcen tlur <-!hmoitlat noidi ntii) ihe inner niarffiiu' of tlie 
orhitiil ^iirfno(-<^, are n i^iTini of doproMsiniu) forming the ixinlt-i of cel)§, and two 
truii^vi-rw gnnivvf. The*' iire coni|>loii>il hv arti<-»iluiion with the lateral nm»«s 
of ill'- ffhnioiil to form, ivi?|>pclivolj-.thfWAnio(W«/i-'V/jt an<l i\it^ anterior and jiogfe- 
i-i'ir ilhmiiidiil iintiitn. The anterior winal Intn8iiiits the nn^il mrve and tlie 
anterior t-thiiioiiliil vi.'>wli! ; tht- fKwt^'rior »ituil, the posterior ethmoidal vessels. 

The eercbnil lOiface fornit^ a <leep coneaviiy, enrroiii-heti n|x>n but t^lighlly liy 
the eonvexitv of iJie upper curliice* of the orhital platen, whieh form the greater 
pan of thv th^^r of ihe anterior cranial io^a. The orbha) plates ami the adjoin- 
ing bone preiienl inarl(e<l tleprcsfiioiii^ and rid^fi fur the Irontul coflvulutions, 



TKOCHtlin 

nHr> t la wBii^owiTm. notch 

"IBOC 




'la 11 pnocc** 



Pn. £10.— Tltc lYuDMt iHiiii'. uiMi tioiu bulAW. i.Tuilal.) 

Eliu-whi-rf the bone is j-moolher, cxeept for a nie<1iaii furrow, tlie jrtmlaf mtlcus, 
niii.-* -(jiftB from the ujtpcr border, with pits for Paoehioiiian bodies on liolli sides, 
and iiarniw-^ down bi-iow In thi- thin, proniinenl frimtnl frfM. The superior longi- 
ludiniil .■>innH i^ KhIi^-iI in tlie siileii.i, tuxt the faix eenOiri is atlaehed to the crest 
and (he ridge.H of the siileu.i. Tin- lerniination of the crest, by artieiilation with 
ihe erii'ta galli of the ethmoid, completes the /ommwt «eci(/» (" blind h«le"(. 
When not closed l)elow, llu-i t'orameu transmits a small vein from the ritiw to the 
superior lonj;iii»linal Hinti!^. 

Border* and Articulations. — The jKuderior boMer arlitndhtcis with tlie parietal 
bone in \\ic cortmat «ii(i(/-<-, nearly aw far ontwartl »« a roiish irinnpiilur Mtrfaw. 
This lrian<;ular surface articulates with the grcsit wing of the jiphenoid, and fornift 
the poxlerior half of the mitcr margin of the nrbilnl pliite, 1 1 i!« cnntiniioti^ behind 
with the thin [fosterior niarjriu nf the orbital pluli-, «hieli artiirulates with the 
Miiall wing i>f the sjiliennid. Tli<' nuilur bnm- jtrliciilalcs with llie fore jiart of 
the outer margin <if tlie orbiliil plate, 'flit- (>!inilli-l iiiiier bonier^ of the orbital 
-Mirlaee ariii-uliite willi the- iw plarjuiii of the ethmoid bibind and the laehrymal in 
from. The margins of the i-thnioidal notch artiiHilnle with the cribriform philc 
<>f the ethmoid lalemlly, and the eri.-ta giilli in fnmt. (The arlieiilutionii of the 
na^l notch, proce-ss, and spine have lieen deseribed above.) 

fhgifioatunt priK-eeds fnun two et-ntres in the membrane at theHteof (he frontal 
eminences. At binh there are two segtarate lateral halves. «>on united by the 
median frontal or meto/iic snfure, which is iLsually oblitenitiil by owifiention, 
except for a trace at the glabella ; but sometimes it pentiv'tit (liroiigliont life. Tlie 
fruntal i<inii«i-tf appear about the licvenlh year oh forward growiha from the ante> 



lU 



THE BONES. 



t\»t ethmoidal wlls, sml incrpnst' up lo oI<i ap-. Thoy irniy in%-ndo and crtr 
ov(rr till' roof of llie orbil i^uilc oxt<:ii»iv«ly. 



THE TEMPORAL BONE. 

The temporal ("teniplw") tionr (Figs. 211-214) forms part of the side and 
base of the skull, coDtuin* tin? oripin of liriirins;, and articiilntci^ with tlie lower 
jaw. Although it i" nsimlly ik-.-scriiji-d in thrii- [sirts — \ir.., )ii|nuin»u», mastoid, 
and petrol!)! — j.liv throir jmrts sc|Hiraliltf at hirth are ihi* MjiiamuiM, pctro-mastoid, 
siiitl lyni|«itiic. 

The SdUAinoua FortioD. — This i.t a thin plaie, which c-xl<-tid» iipwanl niid forward 
fU riizhi .'ingliA (•■ tin- [>etroiis, and fonii.-i part of thesidi>>w:i]l of ihi- middle fowsa 
of llic- i.kiill. Thft oiilrr mirffiM, bnt (^lightly convex, U smoiirli, t-xi-«-pl for a vvT- 
tioal f;riHive above the external auditory meatus tiir the niiddlt- lon)[K)ral nriery. 
It forms part of the teaipoml fo^^a, which is separated from (he ina.'«ioid surface 
behind by the curved mpramantoi'd cre»t This crest is contiiuied forward, jusl 
above the external auditory meatus, to the sygoma {"yoke"), a pr«ce.-« of biiiie 



i 




Fi«. m.— Tbi> ritfht wnponl tKni«, onUr ■nrfaeo. Tbvdottol Uom ltidleal« the Una of ntnre bctwiMk 
•quanunu, dluIoM, and iriqN&le poitlou. (Tciiui.) 

which projwis outward in a shelf-like manner from the lower ]»irt nf this surface, 
aud then, twisted on iL*elf, eonlinue* lorward. In iiK Jorwanl itnijcctiun ihe 
smiMth inner surface and lower border c'^'e nHfitn in tin- nia.-weter, the sharp upi>er 
border gives attachment to the lemporal fascia, and the serrated and bevelle^i 
anterior extremity articulates witli the malar. Two ridges, or rooh, extend fn>ni 
its base, the posterior backward and the anterior inward, enclosing between tiieni 
a Imnsversely oval, smooth depression, the r/fciioid j'omii, divideil into two (Mirt* by 
tlie nearly transverse JUgiirc of fitti*ri; For articulation with the lower jaw itie 
front half of the fos«i is coated with cartilage, together with the convc.v marly 
transverse ridge, the nnincniia rtriictUdrin, which limiti' it in front and forms ibc 
nntcrior rof)t of the ziiffnmn. At the outer end of the latter root U a luWrcIv 
(pri'glenoid) for attaehmi-nl of the extcratil latenil lipimint of the lower jaw. 
Till' piisli^rior root dividiii into two branches, of whi<li tlic upper is the supra- 
miist'iid cn-st, and the lower eu4is in front of tin- (■xtcrniil lunlltiTv meiitus at tlie 
Gluseriaii fis«ure as the jionlt/lenoi'l jimttxt, very pri>niiM<-nI in voiiUf; bones. In 
ftonC of tlie articular emineni^e '\» a small, smooth triangular surface belonging to 



THE TEMPORAL BONE. 



18& 



tliv n'^mntio To^imi, anil M-inmitrd fnim tlii> tcmporul surface by a slight ritl^. 
TIm- rstomnl |itcrvp>iil hiiif^'Ii' f;!kic.» ovit this siirfaw. 

Tin- inttTHiil mtr/tuv is miirk<il hy iiiij>R«>.-iun* I'or tln' OLTcbriti ('(involotions 
ami bv fj"""'«'^ f'^" '''** ii>i*l'll>' n I (tiii 11)^^11 1 iirtoricK, Wln-rt' it joitis tlic |H'trou» 
IMiriion i)ivn> U »et>n in young, nixJ oftt-n in ul<l, hoiK* thv n'mitiiix nf the prlfo- 
mputiaont nttuTf [Niioiing t'rnin lh« anglt^ b<>tvr(;cn lh<-^ two portiiin" in fmiil li> the 
iMirifiai notch iH-twerii the ^tiamons nnd niAHloid ttortiomi b<-liin<l. 'Die nrrlird 
'Hinfer iK'lwfvn tlioso twn aiigb's nr notolio.'* (ii-.-«iTin(>^ nlxnit Iwii-lliini!" nf a cir- 
c\v, und above is thin, bevolted, and fluted on itH inner iiurfact^, bvcrla))|>iiijj the 



/. 



tVOAHk. 







«auieucTu* 



UKTOIO 
FOHAIKH 



FlO. 211.— Tbv rltflit IVRiiiUiml bunu. t1i>u«iI (Vihii Uiv mala! pUn«. (Tntat.) 



TOri<'t«I, and in Cnint is scrraU-d and Iievelled on iin inm-r surfiiw above and on 
ltd out«T siirfaw below, articulatinjr with tho jrreat wing oC the sphenoid. 

The Petro-mastold Portion. — Tliis segnifiit of thf tenijmral is ati irregular, 
four-.iided pyramid ut' very ilene* bone, whose rough truncated apex U directed 
forward and inward to the foramen laccriim medium, and whose base, directed 
outM-ard and luiekwanl, is formed by the lt*s denfc mu^toid portion. It ts usu- 
ally deftcrilK?<] as tliree-Hided, the fourth or outer wiirfaee Wing mostly rovered by 
the tympiinie bone. 

The nuurtoid portioB "f the pctnwal pn'wnti* « triangular rough rsfimtd mr~ 
_^w, prolonge<l downwiinl and forward into tiie nipplf'shapiil tna»loUi pnx'nat, 
whieh ufftmU alliiehmenl to the nteriKMnia-sloid, ttplenitiH enpiti.t, traeliehi-iiinxloid, 
and <K'«^ipitulif. liilernal to llie ni:iHioid process in the deep dif/tii4ni' t/rooce tor 
titedigiwtrie muse!", internal to which i* it wkTlluw grocive for the occipital artery. 
]|ii intfriinl or ctiyfintl mir/ufr forme ii i<iimtl pari (if the [Kislerior crcinial foiv-a. 
iinfl i* »e[Kir:iti-<I fnuo the petniwl pyninii'l by the deep groove for the f-igmoid 
jH>rti»n of ihe liitenil !>inn-«. Tlie uiiiMnlil foramen, transmittitig n vein, ojHtis 
liilenially on or iH'nr the rear wall of this groove, and exiertmlly near the |m«- 
lerior Imrder of the nia.'<ioi<I jiortion. The nnpfr border of this pf^rtion uriieiilaltw 
with ihe jtarielal, tlte pont^rior honier with the occipital. Tlic siitiin-liiu- betwwn 
tite ,'iiiiiaaioiH nnd ma-toid portion!^ 1ie>4 a little below the »upnimitKtoid en-st, and 
riiiw fr<ini the |ictnetil notch to the middle of the external iiie;ilii«. The mastoid 
pitKWMs, nearly t!;tt at birth, becomes pronouneeil externally about the j^cond 
year. As it enlarges, it beei.imes filled with a nmnlier of eoniieeted eancelUiiis 
BpoceiS which about puborty an- in whol« or in port converted into airw^ells {wag- 



isii 



THE HDNEH. 




MASTOID CELLS 



Via. 'il!.— Scpilnn thfiugh ihu miis- 
liild<:cll>.ahawlnu tbrlr cnminuolcatiaa 
w IRi lb* niliUlu t-jtr. iW. W. XmoJ 



Uiid edh). Thpso ape coiiDc-ctL-d willi ii liirjr*'r imvity, ihe mnxtoid antrum ("cave"), 

wlimli is pri'senl niiti iv>m]KimtiveIy lurgo at liirtli, 
iiikI i'oinmiii!i<?aIen with the up|<cr jKirl of tlic pii<l- 
dli' inr or tymjiamiiii. The autruin i*' WuiuUtl 
cxttTiially tiv that part ul' tiic f-(|(iniuiiiis jKirHoii 
bi'Iow tin' »tii pill mastoid crc-t, wliicli i» fXiMcdiiipIj* 
tliLii ill i-iiildn.ii, wliilc -ii|K-riurI_v ii <.-(iii(iiiii.-iii'>i) 
bai'kwiird uf tin* nioi' ul' IIk- tym|niniiiii (in/mnt 
fi/mfniHi, " cover of the dniiii ") wiBinUiM" il from 
the tiiKMle rnminl fos,-ji. 

The petrous portion. — Of tJio twii intraciiitiiiil 
:slirf;iri'!S of lliii* piirlii.'!!, tin- unKtrriin- xiiWricT Imiks 
hiu-iiwuiil, imvard, iiiiil ^ii^litlv iipwiiru iiiln liie 
pcwd-rinr t'orvMi uf thi? liii>f ul" thf tikiill. Fi-"!!! 
iH-jir il.s iH-nlre the inlimol uutlitori/ inealuM, nliicJi 
transmiu the iiicial and auditory ucrves, passes 
oiiiwaril for abmit tw^i-lifths of an inch to a plato 
of bone, llio (rnniiut crihrona ("sieve-like layer"), 
Tliis id HO called from ihe Dimiber of larger and 
smaller apertures for the 6ubdivii?!on» of the 
eighth or auditory nerve on either side of ii truii?i- 
verwe J'lli^ij'onn (" siclcle-sliuiied ") <rrft, above 
vrhieh, in front, is tlie intertml oiifiei' of llie tuptc- 
iliii-t iij Fit/l'ijihiK tor th<' ccveiith or tiieinl m-rve. 
TIk- iKjiiediiet of FullopiiiH ]ui»<'.'< niiluanl to tlie 
gniii, when- it licniU backward to pii!w nlonir iibovi- mid inii-nial to the tyni* 
jHliHitn, behind whieh ii bends sharply iKwiiwai-d internal I" the ojH-iiin); between 
till- tyin]uinnm and antrnm, and torminatea nl the itliilii~miifUiu! jm-<niini . IMiind 
the ineatits is the smiiil, nlit-likc opening of the aiiunhiiiv* t-i-itlifitili (" water-pipe 
of the ve.-ilihnlf"), oecnpied in the adnll by vi-siMjU and a pitN'ess of the dnm, and 
above and in fi-ont of the latter ia a small ojieninj;, the remains of the Jtoccvtar 
/dmmi, very lai^e in yonug Imiies. 

The tinttrior Jtur/uec looks forwanl, outward, and npward into the middle 
cranial fossa. A depression is seen near the apex for the (iasserian ganglion. 
Behind and external to thiu are two small grooves leading haekwartl and outward 
to foruniimi — the larger and internal to the /iiofim (" gaping ") /W/opiV. which 
lead* to the genteutiite }r;iiiglion in the nqnednet of Fallopnis. ami tran^-mits tho 
great snjM'rfieial pelrtwil nerve, while the smaller and external is for the :^niall 
petrowl nerve, [{■■hin<l these, antl Ix'tween tin- |>etio-^<jiiamous sutuiv externnlly 
und !in cniiiienee forineil by llie "UjM-rior wmieiixriilar eanal internally, llic Iwrne la 
tliiii and foi'in^ the roof of the tvtnpaniint. 

The hifirrlw or litittiJiir mirjnrr prceiit)" |K.ii*terior!y, In'twccn the mastoid niid 
Ittyloid pnK'es,*e>, the -ityh-intiicldiii ftimmrti, the exit of the fiteial riiTve fi-oni the 
atliktliiet of Kit1lopti]!>. The '<lt//<iiil /rvri-f.^ iiwlf projeet.-« downwaiil and forwanl, 
for Il0^^ildy '2 inelies, fi-om its base, whieh i- iinlH'dded Iwtween the vapnal proeesri 
of tlie fym]Minie hone and the petrosal bone. 1 1 giver* altaelnu<'iit lo two ligaments 
and three niusel<»<. Interna) to this foramen and pii>ee.-w is the .-mall qiL-idri lateral 
jiifjiilar Jimi, with whieli the jugular process of the oeeipilal unites by eartilngc, 
wliieh ossifies about tile twenty-fifth year. In front of and internal to this fiicct Is 
the smiwth. deepju^uirr/o^wf, whieh with the Jugular noteh of the oeeipilal e<)ni- 
plet*-!? the jugular foramen. In front of the fussii is the i-oriAitl J<nrainrti . the lower 
cnil of the riirnliii cnmtt (for the interiiid eamtid artery) whieh aseends verticidly, 
«nd then jwiwei' horizontally forwanl and inward to the outer side of the a]M'x of 
the bone at the/"r<imoi /(nrrtim /nrdium (" middle torn hole"), Interniil to the 
carotid foramen and niiehing to the ap-x is » ipiudrilnlonil surface for the origin 
of the temxir tym|Miiii and levator [lalati mu.-'eles. SmnU Fommtna im Iki* Ntir^ 
face.—\. Bi*twet<n the jugular fns.sa and the eaniti<l forainen in the tpnpanie 




THE tkmpohal boxe. 



t87 



oafta/fTHAw for Jacolwou's norve {i\w tymjiaak bnuii>h i»f ihfi j^loL-^o-pltan-i^rml). 
2. In thr jii);iibr fwwa m the fontmen for the aiirii<iilai- branch of i\w vutrug 
ucrv-v. 3. f^iimll ivrnpiinu; bninvlics of the carotid )>li>xu!i pierce l]ie wuIU of lite 




NOTID CAHU 






■^•TVtDV4aTCH& 
rORAXM 



Fra. 214.— The rlgbl Umpa«»l bone, tlCITcil from below. (TCflnl.) 



CMfotiil aiim). 4. T)i« n<]t]i'()iiri of rln- oiHUilcn l)c}riii!> in u triuiigtilar cleprCHsinn 
uu lilt- |M>«tvrc>-infi-rii>r iiiiir};iri, Jii.->( 1h.4uw ilit- iiitcrnni nic4itii^ 

Thfi niirniw acUnial or lymimiiw aur/nee I<Kiks slji;ht)v forwiircl, and is hidden 
bv \\w tyniinnin pl»I«, oxocnt for a vitriahh- extent oi tlie oiiti-r vritll of the ramtid 
canal in fntnl. On removal of the t_vni|ianio bone thi» 
surfaet- i.* seen to fi>nn the inner wall t^t lUe tympanum 
('■ drniu "). Tn the any^le Iwtween it and (he 1ym]i:inic 
roof is seen the billing of ihe Fdllopian ranal, whii-h 
bends downnrard in the an^lc between the inner and 

Ewterior tympanic eurfacos, and lodges the faeial nerve, 
alow [his is tlie/cnerfrfi ora/(> (" oval window "), open- 
ing into ihe vestihnlc and sitnnted above the promontory, 
which it- gnxivtii fur the tynipiiDie ]i!exns nf nerve?. 
U<-I"W and behind ihe proniontori' in {\u^Jenf»(ra vlnwln 
("round window"), "(M-ning into the corhloa. The 
surface iwirroww in front to tin? l>ony eanaU for the 
tensor tyniimni miirw'lc abovi; and the Eustachian tnlw- 
birlow, whieh are foinplHcd externally by the tympiinic 
plate. Till- two cjinals ure «e(Kir!ited by ihc delicntr pri>rr»H«* eocfiteari/onnu 
(''(■ont!iL<hell-xha|H>"), which pnijccU outward !in<! npward. 

The HUjtrrior furrtlrr, groovtil for the ^npt'rior pi-tro^l ^tnnf, gives allacbment 
to tJi« tenlorinra cerebelli, a pHK-cs)! of whieh bridp?:« over a notch {tripnninnl 
nofrA) near ihe apex of the heme for the pawiige of the Irigeminal or fifth ncr\'e. 
A npicule of hone near the front eml of ihi:t border i» often ix>ntimted by a fibrous 
band, rarclv by bone (nftrt>-aphriwi'Itil tifrmnnit or process), to the i-ide of the 
dorsum tcl!:!- of the .sphenoid, eomptetini; a foramen for the sixth nerve and the 
inferior petro'^1 xinus. Tht^- jMtttfrior tn/mor bordfT, internal to thejugidar fnra- 
BK-n, completes the groove for the inferior petrosal sinus by its articuhition witb 




Fia, 3I^. - i^qumnouii portion 
■ml lyniiimiii- rliiii or Iht' Icm- 
poni Wni- Hi tilnli. 



I 



ISS VIV ''T^/^' JiO.YSS. 

the (xxiipital bone. The aitUrior mipei-idr and anterior inferior bordera are Bhort- 
enetl by articulaliuti with the HiimnioMil and tympanic Iwnes. rewnertivclv. The 
angle bctwct-n the squamous and petrous p*irtions receivi-s the lipini- of llic- tphe- 
i)oi<l and pn:«-nts the front orihw.' of the bony Eiutkwhinn cnml, l>i which th«' 
«artil;iL;inoiif- piirt \- iittuclKHl. 

The Tympjinlc Bone. — In the itdnlt thi« iwirl of the loitipond fumiH the 'y"i- 
i}iinU- filirtr. Tliis c'ciristiliilc-;< the [Mistcrior, imri-itrliriilar piirtion of the gloiintd 
lo^*u. wbi<'h hMlfjcs ]nirt of ihr purulld (^land, nnd i^ >cpuniti-<l from ihf f'(piuniuti» 
portion in front by llic <j! lam-i-inti l!:^iiri\ Inforiorly it fonnit i1h' ^iharp, prujfct- 
"'B ""(/('<"(/(" '^hf.ilii-liki' ") ijtoccxm; .-.uiierinrly it conh-.'*«-ji with ihc Mpiumiim 
jMirtion, am) forms the front, lower, and ]«art of ihf n-iir walN of llie Iwiny I'.vittt^ 
iiitl .iiidit<iry ineiitn:<. Thi' latter projecin uoiwanl in tin- mrvMl, niiijjb, fn* 
m.-irgin of ilie istTuul ituililorif fiioct'M, which givis attat-hnit'nt lo tiic liiriibipi- i 
nons i»art of the exicniul atiditory meatus. Internally it fiifies with the jietfi^l, ^M 
ami lorms the outer wall of the tynifjanum. Posteriorly it joins the mastoid ^M 
portion in the auricular Jisatirc. Iwhind tile external auditory meatus. ^M 

The liouy criemaf (luiUforu mralus is elliptical, wlightiy eonhlrieled in (he ^H 
middle, and directed inwiird and a little forward to the iymp:inum. lli^ intt-nial 
orifice iff fiinuolh mid jrnioved fur the Iym|ianic mcnibRinc; the external orifice- 
ie bounded by the fxlcrnal :iuditory prewcsii of the tynipiinic bom- exvrpt aliove, 
where Ihe posterior rout of the zyjioma bound;- it, Exti-riinily the Gla»erian fitwnn.- 
i» (;h)sed ; iiUi-rnidly it U doubU-, and is oeeiipi*^ti by a dvwi-ndinf; prorei^ of llic 
tc^mi'ii tymimiii of tiie [vetrou* |Hirtioii, winidi Me|Hintteit tin- tyiniiiinii* ami Mjua- 
nici-qi! bones and fonnK miMt of the outer widl of llie l'!ii>liieliiiui and teuKor 
tym[);ini eanids. Ili'twi'm tiiir* pn-ee-w mid ihe lvni|iiniie plati- ibi- li>^ore Irann- 
rnil.-> to llie Iym(>amnii the tynipiinie linineh of ihi' iiiTernal miixilliiiy nrtery, ami 
lodjp-T. the slender pniee-s of (lie m:illcos. Mor<! inienmlly it presents the iimii/ 
of iliii/uier, by wbieh the ebonla tympimi nerve ia.4iies from the lynijiaiinm, 

Ardculntionn. — The lemponil bone arlienlales nlwive with the parieiiil, in front 
with the .sphenoid and nmlar, lieliiw with the mandible, )H?htnil and interiuilly 
with the oeeipital. 

fhsifieadon. — The miiiamniial and tympanic bones ossify in membrane, each 
from a single centre: the petrous |mrlion and styloid process in cartilage, the 
former from four centres, the latter from two. The fietal tympanic t>one forms an 
incomplete ring, which enoloseH the tympanic membninc. It is open above wnth 
it!" free ends united to the aqiiamosal. The defect in the ring due to this o|>ening 
above is known as the notch of Uivinns. Two tiil>ercle.«, one growing from UK- 
front and the other from the back of this ring, meet in the flmn- of the meatus, 
enebwing a fonitiien, which is gnuluiilly (though not always) dose^l, and ihiii? thv 
tymtKinie plate is formed. .Vt birth the mantoid proii-ss. artienliir eminene<'. and 
tynipaiiie ring are thtt, the glenoid fos-st i.s ubaUow, and the hiatus Fallopii u]H.'D« 
at the genu of thvimnal. 



i 



THE SPHENOID BONE. 

The epfiemoift or wt€lg(~bone (Figs. 21C-218) forms a part of all three foEste of 
the base of the skull and of the orbits and nasal fossic. It is ver\' irregular iti 
idia|Kr,aud eimsists of a body, two pfiirsof wingK, anda pair of pterygoid pnK-esM.-i^ 

Body. — The central cnboidal purl or bwhi present a Kuptrun- mrfac, vrhic-b 
in it» hiial pfirt, in llie inwterior ei-smiiil fossa, eontinites the biijiilHr groove of ihc 
occipital ami blunts upwnnl iind lorwanl to a 4ptadri lateral projecting plale, iht' 
d'nvna M-llit (■' Imek id' the widiile " I, The up|H'r angles of the latter imyeei ont- 
want a,H the jxmlrridr rliiiolil ("bed-Itke") pr'n'fvim, \\'h'\tAi give atluehment li> 
the teiiloriinn eeri'lH'lIi. It overbaitg* a deep depro»»ion, the piluilrtry /ofmti or 
Ktila turtricn ("Turkish .-•adille"). which I<idg<'n the hypophyxii* and formri the 
iiithmns or imrniw m«-dian portion of the middle eraniiil fo>u<a. Thiti depreH.sion 
id bounded in front by a tran.-'Veise e]e\*ation, the oHmry eminence, behind which 



I 



THE SPHEXOID BONE. 



188 



on each side projects s small tuberplo, the middle diuoid procma. In fnmt of the 
cmiDencL- tlie slight o}Mie ffr»ove ^tipjMtrts the optic commimviire, aucl ItaiU liiK'rullv 
to tin? of^ie j'fiiftHuna. The surface in frout of ihis is on a slightlv hight^r U'vvl, 
and fonnii purt of the tioor of the aiiicrior cranial fo6». It ends in front in u 
projection, tne rthmoidai gjnne, for articulation wiih the crihrifurni phite of llic 
4M)itnoid, iiml latenilly it i(> coutiniioiii^ with thctum-riorHurf»c(.-suf tJie small wingit. 
Enuh labrnil innn^in of tliv )iupi-rior surfuec uf tlie ho<l}' in bevelled hy the wind- 
ing (vnyriwfM tp-mirr, whii.'h lii«}r»-* th*- tnternul niroiid iirtcrj' iu its forward iiass- 
«■?• and th« cavernous Kiiiii". Tlii- liiiu) i^nd "( iiii» gnwvc is boimdctl on eithfr 
xi'lf l>y II Imiiv pnijccliii", inli-niiiiU' liv the [/rtromil jirocem, which spring*) from 
ihf ■id*' iif thf iNUMr of lliv cliirniiMi m-1Im* iinil fit.* iigiiiniit llic n|>cx uf the petrous 
|i(inii>n of till- lonipoml boi)i% and cxtt rnully hy ilii- /i»^h/(i ("liitic tongnv ";, u 
iliiu lamella pniji-cting tinwnnl and huckwai-d Ix-lwetrn tin- body and lliv great 
wing. Thi' ftoHtf.rior miruuv i.-> iinite<l lo the haMlur pro<.x-is:* uf the occi^ntut by 
cartilage in early lifi.-, and by Ikiiiv nninn in tho adult. On \.\\<- )intrrl<Mr Kiirfner 
the vertical Kpkeno'uiat erfM pnijt^iUn in the middle line, Ih'Iow the i-ilmiuidnl Hjiine^ 
ami articnlates with the verti<-al plate of ilie ethmoid. On either nidi-, MiiK^riorlv, 
are ti»e roinid<:'<l oritiivw of the tim atpfmoklal ginuaat, which occupy much of the 
body of (be bon<.'. They are nnequally divided by a \~ertieal bmins, the »phe- 







ntwih BO- 



r«STia>on cu- 

HOID PROCtBS. 

CIH*)., 

rontHin 

aviki.1. 



HN»u* nmeiia. 



UmAmtH 

■ nnoauM. 



Fm 31B.— Thf ■pbonold Ixiiia. vlf»»il frfpin bIk.vc, iT<-»liit.l 



nnidal itephim, o(>ntinn<:d luiik fi-oni the civhI. 'I1)e^^ opt^ningH and the mirfncc* 
beneaUi iliem are on the roof of the na.-*al foi«MR, ami ihe roiigii mirfaccn on tlu-ir 
lateral wide?! articulate with the lateral ma*«-7i of thf I'lhmoid above and with the 
orbital prow_-*.ies of the palate bonen Iwlow. Much of thi.'^ hurface on eidicr side 
of the creat, internal to tlie arlieular areas and bolow the orifices, is formed by the 
gphfnmdal turkinalf (" top-Bhai>ed ") hones. Tiifse are triangular or conical in 
anape, with the apex directed downward and backward. Thev are formed sepa- 
rately, often come an-ay with the ethmoid or palate Imnee in di«irtiriilntiiig, and 
sometinKs enter into tho formation of the inner wall of the orbit. The ih/'tiW 
in<;/rt*v prctcnts in front a median ridge, the rwttnim (" beak "), continuous with 
thp crest and nwivcd betW'_fn the altv of the vomer. The t^nrfncc on lillur side 
of the nwtrnm forms ptirt of the roof of the pharynx and nawl fos^jc. imil is tKinly 
I'ovcrtil by the vaginal pmccsscs of lliv interniil pterygoid ])]itt<K. FjhIi Iriltral 
ntrfiux giveH attachment to the two wing)i,*nn<i between th<' hitter fornix the inner 
)M>iindury of the ^jthenoid.-il fiKMnif and the back of lb<- inwr orbital wall. 

Tile small or orbital wings are ihin, triiiiigtilar, huriiiontal plnlCf>, extending out- 
ward from the fon- jiarl >if the laleral .inrfaerv* on a level with the cor n-sjioii ding 
]iart of the superior r-nrlaee. Their snuHtth *((«ei-iiw mr/affx form the hind (art 
of llie floor of the anterior cranial fossa ; the tnferior mtrfacea form the back of 



190 



THE BOXES. 



the iiwt'iii' iln- orhiis siiid ilir np]M'r mnigiti nC tln^ s)>lM^noiiUl DMturcH. Tht- st-r- 
mini iiuterliir Ijunlrr .■iriiriiliili-.'> willi tUc. orbilal jiliiU- of the fniiiial lume. by 
wliii-li it anil it.i |Miiiili-il outtT <'.dr<:iiiilij iire Hi|Kiratwl from the j*n-at wiiij^, t-x- 
li-riiiil tf> llif s|il)<fti<>i(l!it li^siiro. Tin- irt'e noxlKnor botrler is refcivfd iiiln llie 
Svlviaii fissure of the br.iiti. It iw ihc boiiiiclary Iwtwwii the iiiiterior and midcllo 
oraiiial fo«tw, an(i end.-* jKisteixi-iiitenially in a liiioh, the antrrlor clhioid ptfiersii, 
whirh jriveti altuelinieiu to ihc anterior fxtrcmiiv "f iho IvnlDriiiiii cerebelli. The 
liuae of the wing h divi<k-d into two root* hy tin- forwuril niul outward pasKige of 
ihe optic jorrr mm, wliieh tnmsmils the opiic ncrvi- and ihe unhlhiilniio iirlory. 

The great or temporal wings jimjccl iiiil>uinl and n]ivviinl I'mni the lower |Kirt 
of the fide^ of tlie Iwdv, and |ir<.-M-nl tiiive .■•iiHiiees — ei'rcliriil, orbital, !ind tt-iujioro- 
zypjmiilie- The eunwivc crn^trnl gurjucc forms pari of ihe iiiicldle 011111111] fowii, 
und jiresents al the fori' iiiiM of ils jiinrtion with tlie liody, and helow the Nphe- 
iioidal li.-imire the forwanlly directed foniiiitii rrifmiiium for the siijkrior nmxillury 
nerve. Behind iind a liiHe external to this in llie lurgc J'jromm oaih; tlln-fUii 
dowiiwarii, for thf^ inferior maxillary nerve. Thi;; part of the bone iniijeet.i liori- 
xoiiially Iwekwaiil into ilie s^liaq) ahr ("wing-like' | itpmv of the sphenoiti, whieh 
(Kvnpies the angle between theKitiamoiis ami petrous iHinion»i of the tem{toral hone. 
Fnnn it,'* uiKler siirfat-e the sharp ipinoim procvss projeels downward, und giv«» ' 
attachment to the spheno-mandibular ligament. The smtill Jommm tpinomani 



tOHAHCH 

OTVHOUH 




rORKMCN 



Fio. 21'.— Tbo iphcnolil bcoiu. rleWffJ frum In ftnnt. (Teitul.) 

perforates the spine and tranwiiit* the middle meningeal artery, grooves for 
whieh cro(i« thi» KtirJisci-. Th« fxtrmalor trmparo-iffgamatiesurCaa} forms part of 
tlie tempornl fuswii above and of the Kvgonmtie fus«i below the tninsverse pfery- 
ffiiid (" wing-like") riV/f/r whieh eroi«i-s it. The zifyminfic vtirfarf looks down- 
wttnl. is <'"iitinnous with the onter Mnrfaeeof the external pterygoid plate, and 
prewiit." the lower oritiees of ihe foramina ovah' and »]iiiioKrim. Tlie nnU-rior or 
orhilal Kurfaee. liwks forward and inwartl. Its nppi'r <jiiadriliiter,il [xirt forms tlw 
greater part of the outer wall of the orbit, whieh is Hepuraled by a ridgi', forniinff 
the outer lip of the spheno-tiuiril/ai'i/ fiiurure, from a small area below, whieh bnik* 
into the spheno-maxillary fossa and presents the anterior orifiee of the fimunen 
roinmhim. The ponteriof border in iti* inner thirt! bounds the foramen laeeruiu 
medium in front, and pre^cnti^ the [Mjwterior opening of the I'idiiiii oiuitl. This 
ejmul tnunels the bii!* of the inleriial pterygoid plate sagittalty ami tnnir-mit.- the 
Vidijin nerve an<l artery. In it,s otitor two-thirds this Imrder artieiilatea with die 
l)etro«il, completing inferiorly a gnjove for the eartilage of the Ivustaehian tube. 
rh<! fxtrmtU hordiT i« bevelled internnliy below und externally above, und artien- 
Intep with the s<jnanuB<al. The iniprri'tr bonier overlaps the anterior inferior 
angle of the piirietal Ijone. Internal to and in front of this artieulntibn in a rough 
triuogulur !«iirfiiee, formed between the upi>cr murgiiiB of the three aurfaees, whieh 



THE SPHKXOJD BOXE. 



1!)1 



artiouIaUi* wilh n ^imihir miigti iriai^ilar surfa<« oii tlx? frootul. Tbe <Tani:il 
Biiil ■■rf>itiil ■•iirliiws fiiiivi-rp- and nieel iii a ^harj* fivi- ItonJcr niiich IxniiuU lli<* 
sfJi'-noiil'tl fiioiun- iiift-rioi-lv. The aiitrikir miirf/hi or mnlur cfKni si'iiarait-f lln' 
(iHiiiul ainl toinjioml siiHiiocs, aii^l nrticiiUtics with tlic nuilur Ihhk- uih) r^tmctini-OH 
with tbe AujM'rinr niaxilUi ai )t!i luwiT iiii;;le. TIiv ul>li<iii<.*ly clonal! til iifrfirHoithl 
/issure between tilt body and tin- two witig« U flwcJ txtvriuillv by ihc fniiital 
lia>DO, aiid Iraiif'initd tit (be urbii tlu- tliinl, fuiirlli, mxiI), and oplilliutmi<; divisions 
of the fifih nerve-, iind llie <>|))itliiilutic vein. 

The tvo ptoiygoid processes rut)»t»l eaeli uf two platest, jiiiiietl in fruiit, but 
diverpinK betdiid. wliieli |>n>jecl downwanl and slightly fonviinl froin (he lower 
ay|>eel of ihe Iuim' of the fjn-iit win^. 

Tbe extendi pterygoid pl>t«, hi'<i:iil and thin, lic^ tti a fl&ni' diret'lt-d haekwiLnl 
iitHlontu*3nl. Tlio iiiltTuiil Kiirj'in-f ntVoriln ori^iti to Uie inteniul plcrvgiiid niii^'le, 
ibe fjrifnuit nur/iifv. (o ihi- cxteninl jitervjpnd muscle. This plate foriUK the inner 
boundiin- of ll»- KvgoniiHii' fitvn, and the outer boundary of tJie pterygoid /cuuii, 
whieh livN ln>twe<-ii and liciiind llii^ two plates, 

Thi- iiit«nul pterygoid pl»te, lunger and narrower than the external, fonii." the 
(iiitnr InHindary ol' the [iiwif'rior naris, where it is partly eoveri'd by the sphenoidal 
pnM%«i of the palate-bont. rmni the upper end of its intcnuil *urfaee on eaeh 
side ft thin ]ilati>, the vaginal proceitu, projects inward to articnlate with the ala of 







Fn-aS.— Thophcnolil bonv. rlrwed Irani Iwhliiri. (Tratut.) 

the vomer, and in fn)nt with tin- upliciioidsil prix'i-tis of the palate, the latter eon- 
vprting » gnmve beniailh the l«»e nf the vaf^iiml priKTw inln tht? iitt-ryyii-judatiue 
ntnitl, l'o«t*'riorly at the Uum: of the intcniiil plate is tlie Mwall ptenfifiiil Inf/irrfr, 
bctwi-en which and the lingida i» Ihe Vidian canal, and helnw whicli in the aIihI- 
h.w M-afihoiii I'onsa, in which the len^itr palati nniM-le ari>es. The pontaior bonier 
in nndonged below into the .■i|endiT,/Kuim/(tr(" hnok-like") pj-oec**, grooved exter- 
iiailv near its base for the jKL-i^iage of tin? tendon of the tenwir jialati inUM;!e, It 
i;i oReu to be felt behind and internal to the last npiier molar Io()th. In front 
the two plates are joined above, and Inmi a Am<K)th triatigiilar Kurfaee, whieh 
forms (lie back wnlf of the .spheno-maxillar\' fo8§a, and pre^enl» Hti(M.Tiorly Ihe 
anterior orifiee of the Vidian canal. Helow, the two plates anr wpanited in front 
by the jilfiygnitl nrArh, which is oeetipied by the pyramidal jH-oeew of ihc palate- 
bone. The ejirlilage of the Eustachian tube m attached ami (supported along ihc 
posterior and inrter ncpevt of the upper i>iirt of the internal plate. 

ArtieutatimtH. — The T^phenoid Rrtieulaie>' with all the other bono* of ihecm- 
niiim, whieh it himln firmly together, and wilh fiv« of the facial bones — viJi., two 
nmlur, two |Mlnte, and tlie vorut, nnd sometimes one or both t^niH'rinr maxillie. 

(Viri'rfin*. — The ligaments noniuilly ivmrni-ting the elinoid pPoeer*es may 
btrcoitie oft-sified. The joramai of Venaliuft, for an einti«nry vein, it* someiimea 
pn«ent internal to the foramen ovale. 



192 



THE JiOXEti. 



CRISRIFORW 
PLATE 




Pti, Jis.— Diatcrsm of ihc titt- 
mold tiiiiiv 111 mn>v<.-p>v. vcrtival 
tMCLInil |TmIiil-> 



OmiifieKUton oocTirs in cartil»K»; from rwclv« oenlrcs in two divisions, a pri- 
aiiil II )>ij.-tt-spheuoi(l, wliifli join lit iln- oliviiry eniineiict?, and are distinci in 
nmnv animals. The liplKUoidul i<inn.-i(-s Iwj^in lo hollow on( the IkkIv in iliv 
sixlfi jear, ijefon.' which tln.-_v aiv <ynifined lo tlie splicnoidal lurbinaie buiKi*, 
which develop Beparatt-ly iu cunllitgs. i 

TH£ ETHMOID BONE. ^M 

The et/tmoiil or mtve-bone {Figs. 219-221) is roughly cuboidal, aiid proJ4^cta^ 
downward from the ethmoidal iiutcKof the frontal bone between theorbit-i to form 

|)art of the orbit!^, iiu«ul fo»«a.', and biue of the cra- 
nium. It is very Iifrht, being Inrgely composed of 
cavities bounded by tlnii wiiils. It eoueiitb) of a ver- 
tieal and a liorixonlul pliifi.', and of two lateral oiar^iies, 
the liist !>iis|H-nded tVoiu lieneatli the lateral portion of 
the horizontal pliile on eaeli i-iile. 

The Fcrliiiii j'Uit'- (onus the upjier third of the 
meilian (though often diileetcil) septum of tlie now, 
ati<l i:* grooved for tlie olfactory nerve*. It projects 
into the enuiiiil eavity above the honzontui plate a& 
the median triantiularcmtop'i/// ("ere»t of the cock"). 
This is most prnmiiunt in front, and ahni^ it» thin 
]»wtiTiiir bonier il f^ivrs aKitehnicnl lo the falx eerebri. 
In front it (li\ iiti-s inhi l»ii hilend alie, which arlicninte 
with the fnintiil, iirid n.^iuiliy I'lmiplete the foninieii 
eieenni. Tlie vcrtieal plate artienlali-.i in front with 
the nn.snl sninft of the frontal and the ei-est of the nii^il bonoH, below and in frvmi 
with the tnangnlar septal earlilage, below and behind with the vomer, and behind 
with the erent of the sphenoid. 

The hdrisnixtitl or i-ri/jri/onn plate » so named from a number of jierfonilionK 
arranged in tbn-e row.s of which lho«t> in the inner and onter mws are Ihi- liiifrir 
and tninsmit the olfactory nerves to the inner and outer walls of the iiannl lo^wi-. 
Thifi jilale fornjs the depresysed olfadorij i/rooiv of the anterior oranial fo.ssa, which 
hnlges the olfaelorv bulbs on either side of the erista galli. On each side of ihn 
fore jMirt of the eneta galli is a longilndiniil slit for the nasal branch of the tiflh 
nerve. 

Tiie Intei-al nuttttfn or /nbyrinthg contain between their lateral aii<l mesial walls 
u niunber of irregular, thin-walled ethmoidal oelh. The thin, smooth, obloug ouirr 
■waK forms most of the inner wuU of the orbit, and i» called the os j/fonutn 
{" smooth bone ") or orbt/at plate. Thu borders of this plate and of the lateral 
mus^ articulate in front with the lachrymal, below with the »>u|K'rior maxilla and 
pnlatc-l>ones, behind with iIk- wplieiioid and ifphcnoidid tnrbiniite iKiiieh. and above 
with the orbital plate of the frontal. The latter articniation eomplete* the two 
horixMntal, triiM?iver>e griKive* in eiieii bone into the ontntur and poMlnioi ti/i- 
mi'i'liil riiniilji. These arlieiihuionn (together with that of the nii^jd pHx-ewK of the 
maxilla with the furc part of the lateral nin.is inlenially) clo>c the exposed half- 
«ells of the ethmoid. The elhmouial cells are linvtl by a continuation of the na^ul 
niueons iiienibraae, and arc divided bv ii transvcrKc s<'ptinii into an anteri<ir and & 
ptislerior set. The anterior si't opens into » ^innons eanal, the iiifinnllhiihim, 
which leads fiian the frontal siniLses to the middle inenlns of the nose; (he 
iiosterior cells open into the superior raeatiis. Tin- i-ells ari' sometime,' tiivifl>-<l 
into [Kistcrior, mi<ldle, and anterior sets, the two latter o[>ening together. The 
iHwrr vail forms the upper part of the outer wall of the nasal fos^^, and is grooved 
for r)lfaet'ory nerves and bltHHl-ves-iels. It i-onsists of the tujierior and middle 
iiirhitmti- Ixnim, which have attached upper Iwrders. hut are free and s^imewlmt 
rolled outward inferiorly. They arc continuous in front, but fte|wrate<l in the 
posterior half by u <:lmnnel, the mptrior mctdtta of the nose, dire<Tied forward 



THE .VAXILl.A. 



193 



Trom the posterior IwwW. Tin- miildlc tiirl>iiiatc t-xtcnds the length of the lione, 
nn<[ ovt-rhaiiffs aiul l)i»im<l^ su|ieri'irly thi- muMlf niniliis ol'the nmo. 1-Vini licnt-uth 
th<- forr [rart of iho Kilt-nil ma.-v> >ii fiimi .if Uk- h* |i1:iiiiini a Inn);, lliiii lamina of 
IxHiv, tin- iinritwir (" hook-likt' ''] ^/ri«vjw pnijfc-is liiiwtiwaiyi ami t«ick«!ini in the 
|otltcr Willi of the nii<WIe mealiis, \vh«re it Hriictilj|l<'» with the ethmoitlal prueesa 
of the inferior turbinate l>nrH% .in<l helps to cloew the iniK-r wall of the iimxiltar)' 



■ ■BTICfL H*Tl 




or inrvMBikULUH. 



rTHHOISillL 




TM. £».— Til* rUtmnld txnii', ti-cn fnui nbui*. (Tnlut,) 



Fio CI.— ThP inl>iD»lcl lionv, Iti Ivit 
lido. (T«iul,) 



A rtiritlatioit oecnf>- with thirleen boDe«— >viz., the frontal and if^phenoid of th« 
rraniinu, uikI tlH- vrtiuer, two ntu^il, two liichrvinal, two niuxillie, two palate, 
■III) two inferior lurhiitiile bonc^t of the fiiLV. 

Onfijirtiliim ]iiiKHtH\f in oirtil.ifre from three i-cntni*— "»c in thu per|ieiiclieulur 
yiiiU- and one in uieh liileml niu»«. Tnic bou>' ethinoidul cells uo not a|)]K-Hr 
until tile tliinl vvnr. 



THE BONES OF THE FACE 

THE MAXILLA, OR SUPERIOR BIAXILLARY BONE, 

llie maxU/ii or upper jmrJ}i>vr fKig*. 222-224) Ibrmi' the lurfieMt rmrt of the 
^fiivial skeleton, iiK-lniliiif!: [""''• of the floor nntl outer wall of the niiwil fossa. th« 
yxif of iIh? mouth, and the fltnir of the orbits^, and in it un- lodfii-d the upper teeth. 
It eoniprises a ii-ntral hollow liijdyiiml four pn !»;■<'«.■«■*. Ilj> A\nw i.- (■hameleristic 
4ff man :ind of hi^ foiKl iind tliir uuhIu of i-inplnyin^ il. Kni);irully, it \r- important 
bfrtiRt itc iiijiiy di-i-^iM-*. 

Tlw Body. — Tilt j'urlut mtt/acf. looka forward and outward, and presents a 

prumineDt ridge, due to the fnngof the e^anine Iwrth, whieh sepimites two idialluw 

leprpflsions, the infiirtr fmutt in fn^nl and \hc fiinine /cma behind. Above tlie 

laitiT and jiLtt Ix-lnw the orbital niarjn" i'" 'h^ hifrtiorbita/ forcini'-n, when- l!ie 

infraorbital nerve an<i artery emi-i^?. The inner margin of thin Kurface lJn■!^■nl^ 

the deeji numal tiuteh, giving atiaehntent lo die mttx parts of the noiic. The lower 

edsv of the nou-h at iti* inner end is prolonged forward into tin- milrruir nii*iil 

fjinte. The conves jioxUri'if or zfft/otnatiti nuijiict in )^))aixited from the liieiul 

Mirfacc by a ridge ascending from the socket of the firsit molar t<K>th m the ninlur 

^procesii. This surface forms the anterior boundary of the Kvpinintie fo.v*a, and 

tii'i up|M'r and inner |Kirt bonnd)^ the i-pheno-innxillary foKKii in front. Xejir its 

p«entiT- on; tlur a|>ertnres of the two or more pmtfrior rtrnlril fniiiili for nerves and 

ve«»'l» of that name. Tlw prominent posterior inferior anj;le b« ihe luberfgify, 

whieh gives' attachment lo a few tibri" of llie iiiternnl ptery^iid, and articulates 

■ along iu rough internal twrder with llie liiberonily of the pal:iie-lH>ne, The natal 

■ httemai tmrfoK forms thi' outer wall of tlie nasal fi^.-^ in the lower and middle 

u 



194 



THE BOSES. 



meatuses, and presents in front a ridgf, tlie inferior turbinate creet, wbioli articnlRt<« 
with tile inferior turbinate bono. Above and behind the snrfate is defieieiii, nre- 
sontinp the large irregnlar opening into the anirnm, Atiove this opening there 
tirv one or two oulf cell^, which complete a^ ninny ethmoidal celhi. Behind it the 
8tirtaci> IB rough for articulalion with the vertical philc of the [Mihite-bono, except 
tor a smootli groove directed downward and furwunl I'roiu the posterior border. 



Martnian dim 




PHAonillttL 
rOHtMCN 

A«BL XOTCH 



Fw, JH;— Ttic rwhl niuttllB. ontCT turftcf. (Taitul.) 

which is compli'ted bv the palalK-hone into tlie jififlrrkir fjiilatine /•nnaf. Tlve /iwrfe- 
rlur htirder is .-wparatfd IVoni the plerygnid pi>n-i-<* of the ^plicuoid by the tuberosity 
of the i)alali>-bone. Behind the nasal proecM and belwivn it and thU (surface 
itiitii'e the lachrymal ffi-oove, which descends with a Imckward and a slitrhl witward 
ineliiuilion. This groove is completed into a caual fur llio nawd durt ny the laeh- 
n'mal and inferior lurbinaie bones, and owns l>i-li>w into the inferior meatnt^ 
The nniootlr, Iriangiitar oritilul or ujipa' «ity<i«? fornix the Hoor of the orbit and 
tiie inner part of its lower margin. Internally it articulates from before hackwanl 




T1M[ SROOVI 



Ft4, 1:3.— The rliihl mtxIUa. Inner lurDiec. iTMlat.] 



L 



with the lachrymal, ethmoid, and i>alate bones. At the anterior end of this border 
ix the otlter ]iart of the upper <jrih<'e of the lachrymal gi-oove. The l>c(^ smimth, 
ponttTo-extcnial innrf/in bounds the sjiheno-maxiUary fissure in front and internally, 
and presents alwut its middle the romtnenoenicnt of the mfraorbltai proovey which 

Ksses forward in the orbital surface to the canal and foramen of the same name. 
•om the canal the middle and anfrrlor dmttU canafg, for nerves and vesi^ls of the 
same name, run downward in the facial portion of the bone. The anlero-extcntat 



THE MAXILLA. 



19S 



marginoi thU ifurfiiw iMiutuI* tlio miijrli iii>pfr suriin'e of the tltick triimgulur 
mtUar prot^rm; which arliciiliiii's wilti llit! inaljir liom*. Tliis jinxr** i» (Xintimioiis 
iu front with IIh* tiu^inl Hiirtiurnnil tu'lunit it it It the xv^foiiiiitii: ifurruw of thv bixh'. 

TIte Hanoi pnn-eioi is u Iriaiigiilnr [>lalc.- uf Ijoiie wliitih pnijecU ti|>WHn) mid 
nlightly inward. It prf^itenbi exteriiatli/ a smooth Hurfni^- continuous witli tlx- fiiriat 
«uriac«> of the bodv. The internal gurfatv U crmaeA h_v the superior turbiniiU- <vt»t, 
whif^h ariicuhiles with ihf middle turbinate bone. Above the crest it iirlienlHto^ 
with the ethmoid (clofiiig ita foremost cc-llht, and below the erest this aurfiti-e forms 
[wrt of the outer nasal wall in the middk- meatus. The serrated xmnmit articulates 
wHth the frontal, the nnlerior border with the nasul, and the potderior border is 
marked bv the kchrvmal grogve, whieh lud^-s the lachrymal sae. The sharp 
{MKterior border of tni^ grouvi- nrtifuluti^ with the luehrymal bone, while the 
smooth antenor l>urtk>r forms the iniKT murgin of the orbit, the point of whose 
junction with the lower mai^in is murketl hv the Inr-Jir^^mal (>iberelf. 

The iifrrninr prorrni i* the ibick, nn.^lKil lower Iwnler of the Iwiie, which con- 
tjiins the <i/rvw/i (" little holloWi*") nr tiioth-MM^kets, oorrcfijM Hiding in i^Ii»ik' and 
numlwr 111 the nK>ti< of the eight teelh which neeiipv ihem. 

T\i<i' i»il»l^ prarrm, projecting horixon tally inwitnl i'nmi thejiinetion of the Ixidy 
aiitl the alveolar ]m>oess,Hrtieii lutes with its fellow of ilu' npjio^iie iiide toiorni ih<; 
anterior ihnt--foiir(lis of the liaiii palate, the up|HT ^urtlK-e of which l)ehing> to ilie 
floor of tlu? no-i', the lower to ihenwfof theniuuth. Both surfaces an' traiisverf«ly 
concave: the ugiper is smooth, while the lower is n>iigh and marked at lis latend 
mar^gin with a groove for the vessels and nerves passing forwanl from the posterior 
palatine canal. The ponlerior border articulates with the honaintal plate of the 
mlute-bone, whicli completes the hard palate, while the mtdian border jomii witfa 
Its fellow to ftirm, Kiiperi<)rl_v, the verlicjil na«a/ creff, which is grooved (o receive 
the x'omcr. In fn>nt of the vomer this crest, suddenly Wcoming much higher, is 
called I he iMCuor crwf, which siipiiortj' the septal cjirlilage of the nose, and ends in 
front in the anterior nasal spine. On eacli side of the nas:it CKBt, where it Joins 
the tipix-r surface of the iJalate, is seen the invi»ur or l<fensoii'»foran>efi, for the ter- 
minal bnuichc«i of the posterior palatine arteries. These two foramina pass dowii- 
wanf iiikI forwuni, and, convcrginir, o[H'n on the roof of the mouth as a single canal, 
t\tr itnln-i'ir piilaHne./'viJin.corwmim (otl»-m and the two/orffrm'nn nf Seur/ia, which 
an- phuiil in front of and In-hind the former in the mcdi:in suture, and transmit 
the iiasi>-|Milatiitenervci>. In voung lionet the 
ffretiuixillnry fiturr extends from thi» fowwi 
on each side to, hut not through, the outer 
alveolar border, inteninl to the e^ntne riockeL. 
The part in front of this suture on both sides 
represents the premaxilffiri/ bone of the lower 
animals, and includes the incisor teelh. It 
is hepcirately formed, and sometimes remains 
s<>ininitc from the ma.<cilla on one or both 
xidcM in csufi» of cicft-'palalc. 

Tlie «ji/ri(Hi Iff Hiff/imore, or maxiflarif 
mnm, in a oyraniidal air-chamber oociipy- 
iiig the bixfy of the l>i>iic, and lined with 
mucou.'< membrane. It« thin walls cor- 
respond to the Mirfaeeji i)f the- IiimIv. The 
apex eorresjiomU to llu' miliar pnieejui, and 
tile liase to the na^cil xiirfaee, the lurge ojten- 
ing in which is partly closed by the pnlate- 
bone Iwhind, the inferior turbinate Iwne 
inferiorly, and the uncinate pr«iee_ss of the 
ethmoid and the lachrvmal above an<I in 

front. The o|)ening, made still smaller by the mucous memhRine, appears in thr 
mitldle awatus of the uose as one or »nmettracs two aiK-rlures. Along tlic lower 







Fm. tH— ThnmaiLllBry iliiiii ikiA itiilrmot 
WlkU tit Iht orbI(. The •pen of liiv •iiim ■n<l 
Ihu oiilf^r wall iif Uiu <>[l>!( trnvv Imii miiovod. 

('r«Mui.) 



196 



THE BOXES. 



iiii;^h: tlic riMit^ of tlie tii-st two miliars often project im« tlic onvity. TIkt imlnim 
may somctiint* be mrily, rarely ci imi)ifi*?ly, niilKlivukHl. 

Artiitilalionn, — i'he niaxlllii jirticuhitcs ivitli itF^ fellow and with llu- iiitMil, 
frontal, laclirymal, etlimoid, palate, voiiitT, inferior tiirbiuato, and malar ))oik>k, 
and (ioiiiclimos with tin." sphenoid. 

Omification occurs turly in iiK-nibraric from four cetitrcB, and 8omo of the luies 
Iwtwt'cu the parts arc often t<) Iw «■*'» in the young adult bosej especially in ihe 
flixir of till' orbit. Tliu untnini nppcarf: in fretiil life. 



THE PALATEBONE. 

Thi' pntafe-hone (Fiffft- 225, 226) is L-ahaped, and is wedjfcd in bolweftii ihe 
maxilla and the pterygoid proccj^i of the sphenoid, forming the back jmrt of the 
Iiaril |Kilate, of tne lateral wall of the nose, and of ihe fli>or of the orbit. It has 
a iKiriz'tiitai and a vortical plate, united at a right angle. The liiber<Jsit>- projeels 
Itackward and <intward from the rear of this angle, and tile vertical plate is 
siirnionnti'd Ijy two pruccwMLs, the orbital and sjihcnoidal. 

The horizontal pUte iinuplctc,« the hard )Mdatc, and jircsents a smooth, concave 
upper mir/'irr and a nmgh fmrr,- mir/iirr, TJic latter presents behind a transverse 
T\AgK which jrives atluelimcnt to the aponenrows of the soft pidatc, connected with 
the fiMiNor piilati mni^ele, Thi- aitirrhn- burtfrr artienlates with the ]iuhite (irtx-ess 
of till' nia.\ill]i; the *'fi/mir(/ /i07*/rr arlieiiJale* with it's fellow, forming the eontin- 
iiAtion iif the iiiv'titl eri-Ht whii'li snpjuirls llie vomer, an<l en<lf^ nl the jiiH>terior 
bortler in the fxixti-riw ihikhI itfinir. The {n-i- anil Kharp jumtiTi'ir hnrdrr bound* 
tJie posterior iian.-> ioferi<)r!y, and give.-i .iltaclimcnl to llie Mifl palate. 

The vertical plate is thin and pii'r«enl> n rough i>ufrc jwir/'irv, which, appliid 
againnt the maxilla, eoni|ilotes the groove near tin- posterior border of (be latter 



•VHtNO-MUI- 
IinC NOTCH 

PM[(tOIDAL 
PIIOC [•■ 




nOBl' 
pTCMi&oiD ron* 
KiM /.'■- -'I he two |alai«-bones lu Ihui onurni i>o»l 

Uoii. liiiTMl vim (Ti>lia I 




Fl'i. SM.— The right Mlalc-tioiio. 

ioiii-t iiittiipi;, (Ti'sna.i 



into Ihe jtanterior pnUiiine canal for the cleseending palatine nerve and vessels. 
Behind the groove is a smooth surfeee siiiieiiorly, forming part of the inner i»-all 
of the nfifien't-iiiajriKarif fagita, below whicli the (itirface is rough for articulation 
with the pterygoid pr-xM^ss an<l the maxilla siiceessi vely. Jn front this surface 
overlajX'^ and narrow, the opening of the antnini by a thin pr<>jeetinn, the jimjcitlarif 
j/rocenH. The mjM-c or iKH«/«io;Wef presents the hi tKi part of the inferior and middle 
meatuses of the nose, each limited aljove by a tninsverse ri<lge, the turffimite crenf, 
artitujaling with the inferior and middle turbinate bones n?*i>ertively. Above the 
Up]H?r ridge the two proeesM"; aseenil, sijitiniteil liy the deep fpfimn-jm/nlinf notrA, 
wliich is eonvcrteil into a foninieii of the wine name liy arlieiilalioii with (he 
itphenoid bone. Thix foramen eoniimtK the nplicno- maxillary anil na^sd fassK, 




THE VOMER. 



197 



■nd trancmits the sphpno-imlaliiM' arler}- and nerve. Al ihv ltiw«r t'n<l of «m;1i 
jiroce»H inuTimlK' is a [grooved BuHacv entering into ilie .initfriiir meutii!'. 

r The fivc-nideJ orbiUil pi-ocem siirroounto the nnierior border uf the v«rliciil 
platv, uml articuliitcii wiih the nuLxilln in fmut, the liiiWnoid behind, nnd tlio 
ethmoid internulk. The ethmuidu) wrils or iho aphenoiual sinus niav extend int" 
itj» hollow iKMly. Of the two fwe wiirfncfs thf -iuwrior forms the Tvar ai^le of 
the oriiitiil floor, iind the exteniiil IikiUm into the sptieno-maxillurv fos»i, while tho 

[bonier Ix-t ween them )»)iindi« thesphrno-niiixilliiiA' fiwiwrc inlernally at iw hind end. 

The nffhrnoitUil yiix-i.-'iH ctirv(« npwiinl ami inwnrd, and ariienhiteH externally 

iml Kuperiurly with tiin lut^e of ihv. mli-nmi plcr^goid pltitc and uf the epbenoidal 

body, eompleting with th(^ former l)i« pu-ryjru-jndntine ejiiiiil. At itji lower part, 

fin fn>nt, a fnmll wnrfaet; VmV*. oiitwAi-d inln ihv Hjilwn if- ma miliary foesi. The 
inm-r isnrfiicf lo>ik« into the na-sil fo*iai, and nbove, where il totivhtv the nlu of 
the vonn-r, forms a [an of its niof. 

I TIk- Itiltmmli/ or j/f/nimuinl procrim is wedgt-d in bct«'«-n the hibcmwty of tlie 

'tnaxilla .iih) iIh^ pterygoid procesi^ It iircHentn cxieninlly a smiill fni- i^nrfaec in 
tiie eygoniutie fcMisa. Foateriorly it fillii thi- pterygoid noieh, and comjileten the 

LpIiTygi>i4l iix*M by a smooth triangular unrfaee lying hetween two rough gnnivtw, 

• whifh artientnte with the antt-rior Iwrder* of the two pterygoid plate.-.. Inhricirly, 
near its junction with the horizontal plate, with which it is eoniiuurtus, are seen 
the lower oritiwH of the aeeessory. posterior, and external palatine canals. 

ArtienlaiioH. — Tlie ixilate articulates with iti? fellow, the vomer, maxilla, infe- 

^rior turbinate, sphenoid, sind ethmoid. 

(tsaififation proceeds from a single centre in the membnme of the na^il capstde. 



THE VOMER. 

The rtinuT (" ploughshare ") (Fig. '2'27) is a thin, irregular ()nndi^1att'ral pbiie 
forming llie lower and baek part of the nasal sepinm. It is usually deviated 
fnini the vertical plant-, most ot'tcn to the lefl, Rich fatcml mirfritv is covered 
with rnico-jierioatcnm, and presents a faint groove running downward and for^ 
ward to ouodiiRt the na»i(>-pahitine uerve to Scarpa's eanaj. The thick aupfrktr 



■MTCKIOII »L< 

Tinc onoovi 




HAHO PAL4TE 



Fiu. s::7^^wnial Kcilon <.f rbfc.a little to th« lelt uf th* mlildlw lint. dia>lD«: (hn romn uid lli nUlloiu 

(Tntot.) 

fiort/eraplita into two a/ar("wtniFi"l, whieb embrace the rcwtnim of the snhenoid, 
irhile their matins meet the vajrinal nrocesse?' of the sphenoid and the sphenoidal 
'prDewwes of the palate-bones. Tile ooliqiie initrriiii- harti^r joins the vertical plate 
Fof the ethmoid above, and below it i» grooved for the septal cartilage. The mfe- 



198 



r!or bordfr in received iiilo tlie ffroovc of the nasal crest of tlie miixil1n' «ii<l 
IMilatc-borwB. Tli« Iruiieated nntt-rior niu/ie fits in iHrliimI thi- iiicwor nvsl of the 
maxilltv. The ihiii, frei- posterior border ecjiurat*-!- the two inwli-rinr iian;-. 

OnMijirutuiii [>roooixl9 from a einslc cvntre m meiiibninc-, uiul foniiH two lanic-tlse, 
which Ltiiiso the alMorptiou of the luterveniDg curtilage. 

THE INFEIUOR TURBINATE SOME. 

Kach inferior furhinatf bom (Fipi. 2^8, 243) in a ecroll-lik« latnella whidi 
separates the niidtile iVom thi- iiifi-rinr imutiu <if the iia.^al fn8-.a, aii'l is attached 
alioveaiKlexttrnoliy to thcoiiHT witll nfthc ii<wi',hiit is I'roe below and interually. 
Ita convex inner vurfiivty mnrkinl bv pits siud limgitmJiniil growve-i for vcs»*!b, onus 

lielfiw ill the convex, ihieketifd jrrf bordtr, 
whicll is mlW ii[>on iltelf. Tlic sittaehcd Hjtper 
marffln artieiilates in fmnt with the inferior 
turbinate crest of the maxilhi, behind wliicli t( 
rises iibniptly into the InrhriiuKil jirwr**, wliioh 
articnlates with the lacbn,mul biinc iind helns 
to clo*c the lachrvmal nmnh Behind ihi^ w iW 
mnxUlnry ■pnirriv, which is beni thiwnwiird and 
eI<>»i-H lh<- liiw<-r purl of ih<- iijH-niii^ into the 
Hcitnim, Ahnve iind bi'hind iIh- hitter pr(KV!w ihi- •■flimuiilnl f>r<jr<*» ri^c* to join 
the nni;inali- priN't-.v« of the i-thinntd. Thir ]MiKtorii>r jwrt of ihif margin is atlaehi'd 
lo the inreri<ir hirhinate cre--«l uf the jiahite-bitne. Tlie posterior itngle is sharp, 
lilt aniftrior intirt- blunt. The nutf.r mirj'ncf i.^ concave and grooveil, 

Oasification. — This bone ossifies fn>in a single centre in airtilnge, and may be 
regarded as a detached portion of the ethmoid. 



ETHMOID 
PROCISB 







?ra SH.— Rli;hl liir<:t!»r turUInnlu banc, 
axtvriiml •utfai'v. (TialuL) 



THE NASAL BONE. 

Tho f.wo'obhnijT jn/W Imunt ( Fiir- 229) form the bridge of the mise. The 

Jiifiiil tiiirj'iui' of i'«eh is vertieiillv e'«ieiivc nliove iind ennvex Ixdow, nnd imni>- 

versely convex. 'l"he jionlerlor or mnui! •nirfitn-, transversely i:on<5ive. is rough 

above, where it reali* niKin the nasal jirocinw .if Ihe fi-ontal. IJelow it forms part 

of the roof of the nose, and piv-'HMiIs a hmgiUKlinnl f^riHive tor thi^ nu^ii nerve. 

This gT(K>ve ends in a .small nou-h lu-iir llie inner end of (he 

JXL^ ''*'" (ou-'tf border, which attaches the lateral na.-al lariiliifjc, 

^^■i^^ The liliort, thick upper border articnlatcs with the niisul notch 

^^H^^F of the frontal. The longoM^ir io/^f/- arlicnlalej< with the na.-^l 

JBjI^^I process of the maxilla. The inmr horda; thicker aliove, nicet8 

/oT ^* '''** "^ ''"* t*'"'^"' ^'''i which it is prolonged haekwani into a 

I ,{ \ median crest, which fnmi al«>vedownwanl rests Hpon the na.-<al 

J/O-^-AJ Kpine of the fnmlal. the vertical plate of the etliraoid, and the 

f^ ^ ccptnl enrtilasjc of the nof-e. 

(fiMitiiiitiiin pniceinlji from a sinijlc centre in membrane 
overlying ciirliliigc, which i» ubsorbed. At birth the bone is 
relatively hroad. The sJiupe of the nose depends largely 
upon that of the-se bones. 



Ku, £S>. — Ntuial 
bom*, vli-wi^d fruni 
bofiire. (T«tul.| 



THE LACHRYMAL BONE. 

The Inehrinnnl hiiie {"x umiim), '' iiatl-bone"(Figs. 230, 231), id a thiD qiiadri- 
lateral scale of lione forming the front of the inner wall of the orbit. Its exierfud 
or orbitnl ttirfficf pre.ients a larger, fiat hind or orbtlnl pitrl, and a. Bnialler grooved 
fore part, forming the laehrifmitl tmlrumtr i/niorr for (he lachrymal sac. These por- 
tions are se para te<i by n sharp vertical ridgi-, the /(Wu-ynwi/crwrf, which is prolonged 
forward at its lower end into the hamuhtj', which often articnlatc!! with the lachrrnia] 
tubertrle of the maxilla, and Iwunda the orifice of tlie lachrymiil cwnul externally. 



THE MALAR BOXE, 



199 



Tb*- ini^niat mtrfaf* cI«»m>» jkhiw i>f tlie aiili>riur ollimnidnl rell.i above, and infe- 
norlv lookn inio itit- nii<ldl« itii.atiL« of Uiu iiuii«. Tlic aiiicriiir bonier artioiilaieii 
with the nasal ))nx>c^ of ttio nmxilla, lh« Mi|K-rioi- ^\'ilh thi> internal angular 
process of ibo fnintui, an*) tlie ])ui>t€rior «'itb tlit- orliital jilale of the etlimoid. 








Tta. St.— Itlslil InvhiTlaal bon^. Iimor nirftcs. 
(T«Mnl.) 



Thv infi-rior iKiiifcr ln-liiiiii tlic crest joins the orbital jilale of tbe maxilbi, ami in 
fr«iot it is iiroloiipfd ilowiiMiinl or. tbe ilt-M^cndhiff or turhimil jironnji, which joins 
thv lachr^'iual prcxie^ of tit« inf<Tior inrbinaie bone to eompleie tfae lacbrynuil 
<:anal. 

Tbe lacbrvinal rut^iJUs from a single centre in membrane. 

TH£ MALAK BONE. 

The nuadranfttilar wifl/or bone (Fip^ 2^2, 233) forms iho pi-omim^noe of llie 
chwk hikI hi'lps (o sopsirulo the orbit from Ihe temixmd fiwsn, Tlic khIo- mir/at* 
ise<inve.\, »i)d pixwenlif n(iir its ccnlrclhe orifiwof llii; malar cntial. Tliceoneave 
tuner mtrfacr ]u«>k» into tbv terapoiwl fossu almve, lln- zyp)niatie fossa below, and 
artienlates in front bv a rongh triangular puHiii-e wifh the mnhir |iroeoss of tlie 
muxillu. The four anifles are diregted verliruHy and huriiLonialK'. Thtt promi- 



ra«nTat, •ooctM 











fhi-ZK: — RlRhl nnUr bone. lUIcr inirfiin'. iTctiut.) FiD. aK— RUrtil malar bonv. Isiicr lurfkcv. (TMntJ'' 

ncnt. limited upprr angle or /ronfal prinxM articulates wiih the external nneidar 
prwoc»s of liie frontal, and the prMtrrlor uiit/(c or zgffomalic proi'ttt* is lievelled above, 
imd uriiotilalett wit h the end of the zvgoma. The •■iiiiious tevi/iortil border l>etween 
these two un^le^ is contintion^ with the upper edge of the xygnrnti Iwlow and the 
t^mjKirul riilfp' nlwve, and f;ivc« altjichment to ibe (cmpoml fjiscia. The po/^n-o- 
iii/'ri'ir or trtei/tifierie hnr'W eomplctev the lower ctlge of the zygomalio arch 
and (pve< orif;in t" sitnie film'.* of ihe maw^-ter. Tbe <tntero-infvrior or m/ij-if/firy 
/finite; iIh- irifi-rior an^jlr, and tbe anterior angle or nio.riV/fli-i/ proccnif urticiilato 
wilh the maxilla. The antern-jmprrior or orhUaf hnnler is curvoil to fbrnt the 
onter margin and the onter half of the tower mar^n of the orbit. From tbi« 
border the curved, triangular orbiUil prucmH proj«cti« tMivkwnnl nnd inward, and 




200 



THE MOXES. 



V 



foniitt tti« anterior boundiiry of tlic loiu{K>nil fusHt iind the furc part of the out 
Willi and Hour of tbc- urbil. it .-irlk'iiliit(':t iil>ovc uilli tin- tVoiituI, itiid Ixliii 
wilii ihfgri'at wiiigol'llnspln'imid and tin- urbitiii iiliili-ol' the mu.xilJu. Ikiwit-ii 
llic iirtkulations witli the Inttt-r two iiont-» tln-iv \*, iiHtiiiltv u tVi-i' niiirgin bounding 
the h|ilieno-niusillarv tis«urr in IVimt- The tfiii/ioriil am] iiuiliir lytnnU, for the 
teni|)(ir<)-m;ilar bniiK-lii;is ol' tlii^ lil'lh iierve, ure wt*!! mi (lie urbilul i^url'ace, 

Oaaijktifion procw-d?^ iti membrane iiiiin two nr simietlnn-s three centres, and 
the adult boue is occitviouall)' divided Uy a IiurizoutaJ suture into two unequal 
parts. 



THE MAin)IBLE. OR INFERIOR MAXILLARY BONE. 



The lower jaii--honv I Figs. 234, 23.5) \» u large, slii>iit:, lioi^se.'lmc-^liapiMl boue, 
fonuiuji the lower ihinl nf tlie t'ni-ial fikeletuu, and artieulaliug bv means <if a 
[Ktir ut' condyles with the gh-iioid (ii'^tK of the toni]iurul bones. It entiMi')'' of a 
eurvetl. rie:irly horixDnliil lioily in front and two vertieill ]H)rtion» or raiiii behiml. 

The body curisist.s uf two iiyninietriejil, lateral halves, wlmse ici/rayi/ivKM 
("1ojri.ther-i;ri)wlh") nr iniion in tlie middle line is ninrki-d on the ejtfruiil lau-- 
/iiiv by a faiiil verilcvil ridye whiih exiiands bebnv into the triangular tiimtai 
proluftrninre or ehin. The i-entrt^ of the Iwise of lilt- pi'otnberaue*' may ho slightly 
deprosscil, and from itti prominent Iater.d auj^W, or Mental ("ehin") Uifinrln, 
the rather faiut external Mlique tine extendi! baekward and upward to became con- 




FMi 3M.— The QUuidibl*. VteiTc*! from the M^l BQit A UlUc In treail. (TcMUt.) 

tinnoti8 with the anterior border of the «)n>iioid process. Below the incisor twtii 
OH each side is the iiifiMor fnHKa. Midw.iy between the npiKT and lower bonlers 
and in line with the .weonil bieuripid liMith,or the interval between the two bieuic 

Sid^, IB the mmlal j'ormnen, trauAmitlin}; the mental nerve and vessels from the 
cutu) canal. The hitrmat «Nr/aee presents at the symphysis, superiorly, a linear 
groove, cndiuK below iu a small foramen, below whieh are two pairs of ffmw/ 
(" chin ") ('i'»rr('/i'/(, sometimes fnsed into a sinj;le median ridpe. The upjwr ]iair 
eivt'.-s origin tii the gcnio-hyoglossi mn^eles, and a small median ridpe, from which 
Itie gi-nio-hyoid mnwh s ariwe, usually takes the place of the lower pair. Uelow 
and oil each side of thi*, and close t<i the lower border, is a rough depression for 
the insertion of the anterior ImjIIv of the dlfpi^itric muscle. Beginniiig uIkivc the 
latter and at fhc side of the lower genial tubercle on iiich half of the bone, the 
internal obli</iie line or mijlti-Uii'iUl riilr/r jNiKses bsickwiinl uml upward to the ivmiis. 
This gives origin to the nivlo-hvoid muscle, .nnd, at the p'wlerinr en<l, the sn|KTior 
ponfltriclor muscle and the ptervpi-mivxillury ligttinenT. Above llie line, on each 
side of the symphvsis, is the sliallow mililiii;/iifil /••rmi for ihe sulvlingiial ghind ; 
and lielow it, at the side, is the imbtntixillHry jhhkh for the subnmxillary gland. 
The Kiiperior or atceolar border on eaeh fade prei>enu the soeketft for the rooti' of 




THK MAXI>IB1.E. 



201 



ih, am! extcriiHlly jiiv<rB ori^riD to tin- Iiuoi'iniit<)r a" far forwani n* th? 
riKr. TIh! injWinr hmylrr, tliiclt, wnmolli, iiihI roiiiKU-il. (ircji-cU Ix-yond tlic 
lip(i«T, mill is K""*'^''''' *■"■ ''"' '"<■•"' iirrcrv lu-iir itf jiinrtion with tliv niiniii'. 

Ttu* nmns i» (juiulHIaii-ml »ih) thima-r iliun l)iv body. Tin- uuloi-Ioi' tlltl]*l')(^ 
i" iii<*<.Tt«<] oil its eAerntd mrfitcf. On the intrrHat mtr/npf, alxnit Ita i»i(l<]l<-, in tlie 
in/rrior tlrntaJ /aramm, It^iti^ to ili(? hifmor dental canal for tho iiifcrioi- ilt-nlal 
vr-*^-!;. ami ncTvi». This caiial i.* ru-nrer th« iniivr siiriaw biliiml ami ilio oiiler 
ill fnml, wliere it oonnects with the mental foRimcn. It coinnHinicnies by a wrics 
of fitva chaiinols with thi; bottom ot" each toolli-.-ookel. The Iront and inner eilpf 
of the foramen is sharp and prominent, forming llic Hiiifula ("liiilf tonpiie' ), 
which gives attachment lo the sphono-niamlibular or long internal lateral ligament 
of the jaw. Buhind the lingiila and Mow the foramen the miflo-hffnuf groorr 
(Mimetimes a canal at tirst) starts in its ilownwanl and forward cour».- bcneutti \\w 
mylo-hyoid ridge, and ioiijit-H ilie mylo-liyoiil nerve ami vcssi-ls. Between llii* 
groove and the angle the iniemal pterygoid miisele i^i inwrled on a nHiffii triiingnliir 
spdi-e. The lower bonier, eontiinioiis with tlmt ">f the body, meet* tlie pcwli-rinr 
htirdcr at the angle of tlio jaw. This is ttaiially slijrlitly everted, arnl pves attach- 
ment posteriorly to the Btylo-nian<libular fold oC fascia. The slmrp, conejivi- up}>er 
Iwrder, known as the sigmoid notch. «e|xinite>i the two pnHVSse-s, and is 4:n>s«ed hy 
the niMiwitenc ncr\-e and arterj-. The posterior prw^^ws, or cowlylr, ^imiount^ the 



COMO. rnoe-j 



OTHiat. 




nrtaion OCH* 
T*L roiuacn 



F^. ^.1 — till- rli;<<t tialf <if Ihi> niiinilihk, Innrmiirnicp. iTnliit.l 

noaterior border on a nonntricteil [xtrtioii, or nwi, on the front of wliich, intcmullv, 
i» a deprestuon for the insertion of the external pterv^iid nin^ele. The t-otidylc 
i.^ eoaves awl transversely elongated on nn axin wliich, pn)!iingc»l, would meet 
tliat of its fellow near the from of the foramen magnum. lis piimiinent onler 
end, lieyond die articular aurfact^, forms a (uftere/ir, to whteh the external lateral 
ligament is attachetl. The thin, eoronoid jirocfKK tajM'rs npwanl and ontnurd in 
front of the sigmoid notch, and to its tip, borders, and internal surface the tem- 
poral mnM'lc h nituclied. Its anterior bonier is conlinnons with that of the ramus. 
Th« inner surface prescntit a ridge, eonliuiious below with the internal oblique 
line and the inner alveolar edge. Between this ridg* and the anterior bonier is a- 
gnM>v<' for the ins^-rtion of the tem|Mhral mnsele above, and, for a short distance^ 
tor the hutviualor below. 

Th<- i-kange* aexoMtng to age fFigs. 23B, 237) are §o ordered that Ihe uppiT 
and lower gums, or iwth, as the eitwe niiiy be, meet in biting. TIuik, at birth the 
angle I»etween the Inxlyaml niinu« w about ITo", Ihe bixly i« Fihallnw mid eonHi^I» 
tnoAtly of alveohir pro(K>N<, nn<l the menial foramen ii< near the lower border. At 
about four rears of age. afii-r the first dentition, the angle U rt^diieed t" HO", a» 
(he body plus the t«-th ik inn<-h deeper. In adult life the depth uf thi' body ha^ 
so inercawd below, in tin- biLwl ]Hirt. that the foramen i» uiidway between the 
bonlcm. and the angle is VIO" to I H)", or even less. In old age the alveoli are 
ahtiorlHHl, the foramen is near the iipiwr bonier, (be hoiiy is basilar, and the angle 



202 



THE BONES. 



• 



i.t innreaMKl ta 140° nr ho, thtiM allowirtj; |1k> fr<in)» to mopt. Unleni the angle 

between tlie raniui^ and tlio body is inc-rc-Jim.Hl wIr'u the body i» slialiow, aii^ 

infancy or old age, only tlic 

fore part of the jaws would 

meet m maeticulioii. Tlio in- 

«rc:iNe of ihifi angli? l<-s»t'U? Iliu 

distaiict- bftivfi-n tlicliDriKoniiil 

Icvi'l of ihu wndyk't* and iliut 

of tliv gnins. TlniH, in old ugi*, 




V\ti. SSt— TIip inuiilllilu III tiilkiiov. 

'(Todull 




Fill. 237.— Til* liiiuiilililu ill •i\<\ nuv. iTi'iliiLt 



tlif low- of llie teeth and ihe absorption of (he jdveolar jirocfss h>wcn« the level of 
the jfiimis; and this level is rai(-ed, i-o an to n-ni-li that of ihe ii|>|ht giim», by the 
ini-n-!it-i' or »lp,ii)ihtening oiit of this unfjlt'. Tliis loiidilion ab'ijidy exist)' iii the 
infanlj and, as the body of the jaw Inon-a'Si--'' in liiij^ht. and tin- lii'lli nrc <Tn|ito<), 
ihe angle i- diininii<^hcd so as to lower the Ifvcl of the rutting odnir of llm l<iw<T 
tt'cth, and k(i'|i tliem tn Hue with those of (hi- n>i|ii'r Jaw. This ehaiip' I'onliniw^ 
ntilil tin- jaw n-ai-hi-^ it« iidnit size. In old t\^- Ihe iticreiwi- of thi.'i angle lenglliciis 
till' jaw »ci that (!)<■ ehin jirotnide^ und ihU tlght^iiit tlie lifif, which 'pn-s» back the 
u[i]M-r liortliT iif ihi- bone in front. 

Otiificittl'iii iinx-t^cd-i at « v(tv early Jioriml from fonr to six i«'ntrea on each 
side, Tlii; piirl from the ?ym|)liysis to the mental foramen is oflsilied in the 
tiiiterior end of Meekel'i uirtilu^re, the eondyle and angle fmm wjiarate e«ntre« in 
eiirlilagi-, and the rei^l in inenilirani-. At birth the two halves are nnited by 
fiiiruii.H tissnc. 



THE HTOm BONi:. 

The /rywV/ (" like Greek letter iifsilon")or litiffinil ion r (Fig. 238) is 
smiill U-^liiiped bone whieh may be felt lit the bitw of the tongue, between 
the chin and the thyroid cartilage. It hat » IhhIv ami two [mire of cornwa. 

The oblong hmli/ hux n smooth, i-on- 
cnve fiiiMfriar mirfiiif, looking backward 
iind downward t4>wurd the ciiiglotli", ItK 
convex inttrcUrr mirjiivi; lofiking iipwait) 
iind forward, i.* divided by a (nin:>ver*e 
and sonH-iiines a median verliral ridge 
into depressions for niii.'>enlnr attnchtuent. 
The miperior brinUr gi\es attachmeut to 
the thyro-hyoid membrane. 

The //»■«!( coriiH« ta|)er backward and 
npwnrd from the eidcs of the IkkIv, ending in rounded tnberclefi to which the 
thynt-hyoid Itgamenti^ br- attached. The cornua arc flattened above and afii)rd 
nttaehinent to niiiti-le». The- mnitll cornua are small w>nical ])ieees of bone, otleit 

farily, and sometimes wholly, curtilnginoui:, \vhi<^h project upward and backward 
n>m the junction of lh« great ourniiu ami the body. Tlieir extremiticfl give 
attachment to ihestylo-hvoid lignnientK, which Kiispend thehyoid from the styloid 
processes of the leni|>oral bone^. 

OtMficalioti occurs in carttlagi^ which lies in tho si'c^ond vii^ceml arch and is con- 
tinuous with the styloid process. There is a centre for each coniii, and for each half 




liynld bnnr, vt«w«il from thplvft 
II <>.| 



THE EXTEHIOU OF THE SKULL. 



203 



of the body. The svnchondnwis of the rr-jH om-mi h Itlj tin- WyAy t^ually riK.tilic.'t 
after uiddle life, 'fhc syDovial :irticidnlioii uf thi> i«inall oornu m-ldoui aukyloci««. 



THE SKULL AS A WHOLE. 



The Sutures. 



Tho 



•if the 



edges of the 



mlitm unr llio <'Ii»«<'ly-lUl<-(i ariii-tilatinns nl the uneven 
boiii'" uf ihc^ xkiili, ill whii'h tU<- !wnii-« are noiuti'nit-d by only a lihrutin galure uirai- 
AriiH'-, (NmtJiiii<iii.-> with ihc jn-rionieiim iind dura. Jti i\\v Iwo syiK-hondroeies of 
Ui(> jii^tiLir aud lioi^ilar (Hiriions of the ()coi()itul bone, :il the bate of the nkiill, 
canilitjfe tDlervcne;! until it ih (H^fiitied in sdult life. The t<ntutx>fi allow the rapid 
smwth of the tikull in early life, diminish shwks, nnd. by beinp alternately 
Bevelled on cither nde, hind the boneis ko firnily Uijii'IIkt that dii^locufion is 
nost to imiMX'iible. Manv of ihein are often, but not aiwayw, ohliteraied by 
<Mv>itl>-nl)oii in adult life. The time when tliiw eommenoeji i« ven' variable, biU it 
a^iially begins where ihey lasi came together — i'. f., near the posterior, anterior, or 
aat(-n>- lateral Ionian el I eit. 

Though tlie sutures arc l>cst ttamcd from the Iwiie* whirh form them, Ihore 
aroaiKl llie [eirieta] bone^ have ret^'ivc-d (-pectal iiamo^ fniin tlicir shnpr, ilircctjon, 
etc., a? the i^tffUtaf (Intrqwiriotjil), the ror-miit (fn>nt<>-])iirivtal), tlir InuiMniilul 
((»ceipiti:i-|iiarietal;, and the /"pininiju" {»niuniH)-|iiirifl.nl|. 

The fonUnelles ("liltlf springs") iirt- nnn-isi fii.il, mombninonx jipa**" which 
exist bi-forv, at, and fur ii time after birth at the nngh-:* nf (he (wrietal bone. 
Their cxisteiKv and iKHfitiun are due In the fm-l. that, whilr iho bnmyt are nnndri- 
lutvral, iK«vili<-nti<m priKvoiU rmlinlly or <^in^nlarly, I'o tital the angl(«< are tno Wl 
to oiwifv. The largi-r, dinitioiitUshiijH'd nntirtor /onfmuilf is an miportanl land- 
mark til innnrilioii. Ii -jtviw for « safety-valve for the rapidly varying intra- 
cranial prcTt.'Un' of varlv intluicy, and rliwiw during llii' xtK^nnd ycni'. Tin- autiTuir 
an<l /xmli-i-iiir Ar/mi/ fwi^/iii-//™ arc «hw«I in fivlal life. The jiOKbTiiii- /•mt'iiirtltt 
i» often filled up Ix-furi' l)irfh, hut iho bon(yi are then nmvabie njKin each oiher, 
and the iriangli- tunned by their margins may be felt a^ a lanihiiark (hiring |i:ir- 
iiirition. Wormian Itoni-.'* oih-n a.'uiisL in tlio elosurc of the lateral inid [HotiTiiir 
fonuini'llv-. 

Wormian bones art' ^niatl, irn'gnliir ii**ich'» from sHpcrnnmemry ossiBc ecntire 
whielt are found in van'ing unmhiTs in the snlnn^w, (■-•"[x-cially in ilio»^c alH«il the 

Erietal Ixmeii, and ehiefly mar the fimtam-lh-:*. They ant iniBst numenniH and 
^lefit in the lainbdoid suture, but mibt be dititinguiahed I'mni |)k- inlrrpurielal 
portion of the ooci])itnl bone- when it tf\irtt-H as a separate bono. .A .imiill oniiele, 
the rpiplcria i" upon the wing") bom; is found in most ?ikulls in isieh anterior 
inUial f>wit;inellc up to the lifteeuth year, after which It usually joitui the great 
wing of the sphi-noiil. 

The Exterior of the Skull. 

The skull is bilaterally ^ymnii-tricai. 'liif sui>sr!or regton InolndeH Uic smooth 
convex i-nrface. It is eovcred by the oi-eipito-fron talis mnsirit- iiud :i{N>nirnro»is and 
the ficalp. It extend-* from tlie supraorbital margins in front to the KuiH-rior 
curved litie* of the ixriiiiial bone behind and between the sup-rior tcinponil line* 
latently. The skull, viewi'i! from above, is bi-oader behind llian in front, and is oval 
in outline, with sltglit proj'cliuus at the frontul and fiarielal t'miiiunees and ai llie 
<H^'ipi(:d proltib'T.moe. At the meeting of the Kigiilal and coronal sntures in the 
hrrifUDi, at the site of the anterior fontanclle ; and the Ininbdu is where the sagittal 
and laml*oii] ^ulunvi meet, at thv site of tlH> posterior fontanclle. The occipital 
protu1)entn(« i# known iv the inion ("occiput"). Kxcopt in vcrj- broad skulbi 
lite zvgomatic arehc* are visible from ubov<'. 

I'he lateral or t«mporal Teflon ( l-'igM. 230, 240) pre^etit^ the tnn^iural fotea. 



204 



THE BOXES. 



f'li-ini'il liy (lie loni|u>rul, parii-tnl, ^gihciKiul, froiila], and malar l>on<^, ntul Dccn- 
pii-d \i\ fiiu tom|Hira) niiisfle. The foKsa i^ limitocl Wlow l)y tlie /v^nniatic uR-h 
i-xipi-iiiillv ami i!i6 ptprvK'*'tl ri<igp of the »[)henoi(l internally. Above it i* 
hiiiiLidi'il bv the (cmpornl fidi/e, whieli, starting at the external angular |»roceJ« of 
llie tViiulal biine, an;hr's iii>ivai'(l and b!iek\rar(l, and tlien downward. Near l\w 
eoi'iinal suture it u«nally divides into a evf/cfior iirid un infrrinr rkli/e. The latter 
liniiU the ori};in of the temporal muscle, aiul '\» eontiiition^ beliind with the •'it))ra- 
ma-^toid crcHt and tbc posterior root of tlie nypoiua. Thi- fiirnicr, \vf* eoiiHtaut 
iinil not ns marked, jjives attiichin<'nf to the teTii|niral f'aiK-iu luid ari'JiM dowii to 
tlie mii^toid iiriKiefi* ni.vir ihi? imtfiiim (" jitsirry "1, wbicli is at tin- silo itf \\w \h«-U-- 
v'wr liitenil fotitanelle. Tiic pirrinii {" wtiijt "). »t tiie sitf of llie unteriiir lulenil 
fiiutaiielk', is whi-n- ibi- [iiirieliil, rrmitiil, sphi-nnid, and lcm]H)raI biim> (miih^ 
tu);etli<.T. TIk' ten)|iiiml fo^ni euniuiiiiiicat''!' with the xy^imutte f'lSita llirougli llic 
o)K-iiing boiin<le<l exteniiillv )>v the /v^>nuilii* amh. 

The zjiijimutfU: ffiXH'i is lumudid in f'niul by the zygomatic surface of the max- 
illa, iuii?nially by the exttTual ])Ieiyj5;oid \i\aU; cxlernally by the Ei>'gomatio areli 



SBIMI 



PHOBTHrO 




Ptii. SKL— ^kiill. Tlrired fmn Uii^ k'll >Jil-:. tliiiwiiw ttiit jirliictpal cnuiliiini-lriR ioIdU. 



and ruinuK I'f the jaw, iiiid sU|>cricirly by n small f rlimniilnr Kiirfacv on the Miua- 
mosjil :iiid by tin- nrwit wing nf iIh' sphenoid inttTMijI !■> tbf plerypiid ridge. 
I'ostcriorly it is liniili-d hvn line di';i\vn Irmii ibc s|ih('iiiiidal r!pin<.- ■■> the ttil>rrele 
on tbo anlfrior rottt of tbv xygoiiia. It ii* uctHipicd by iho ptcr^'goid and temponil 
miififlect and the eomnoid prot-uvs of the lower jaw. luteriinlly, Wtwet.-n its uiilc- 
rior and interna! liDUiidarie.-, is the veiliiTal pM'_i/j/«-mHj-*V/«/i/ jJjmhiv, bi-lwinrn the 
maxilla and the auterior Iwrnler of ibe external pterygoid jiliite. This eonn<KriM 
the /.ygoraalic with tbo ep/ieno-tiiaj-iHiirt/ j'ussii. Above and at right angh-s to tbc 
plerygo-maxillarj- fissure is the nft/ifnu-iiiiixll/ari/Ji'Siir': « hieh eonnccts tin' npixT 
part of tbo Kygomatie and of the spbeno-maxilfary fossp with the orbil. lliii* 
fibsnrc lies nearly burizonially between ilu- free margins of ihe orbital i<uHaoi<ft 
of tlic maxilla and the palate-bone internally and the sjibeuoid externally. In 
front the fn^nru in usually limited by the niular bone, though (he niaxilui and 
sphenoid may ariiciilutv liert^ and cxelude it. 

The i^iena-nutJ-Ul(irii frumu, sbupml like an iiivvrlvd pyramid, is a eniall hpuoe 



THE EXTKIilOH OF THE SKt'LL. 



ao5 



Wtwwn tltir trmxillii aiwl (Ik- nwil of ilic ptprygnid ])rot*>,-. It i*i twumled in 
front liy tin- tmpcr and inm-r jHirt uf tlit- rypumatic- surface "f the nisixilla, 
inlfrnalty bv ifn- vcrlicsil pink' anil tht- orKital ami •^phi-tioiilal ur<>cc-.s«.'f! of 
the [KilaH'-lHiiM', Eieliiiid l)v tlw- moU uf tliu utcrj'goki prDCc*" anil ttii* lowt-r 

C»rt of (he anlerirtr Hurfaop of l\w irrpftt wmg of the splK>n<iiit. Thp apex 
ade into the posterior palatine caniil, the Iwis^- into tho Imrk of ihe orbit 
throiijHi the hind part nf ihe sphemi-inaxillnry flssiin-, liitcrimlly thi? ."pheno- 
palniinc foramen i-»nnet-t-* it with the nasjil fiMw, and l«hind an- «een the foramen 
r<>tnn<him. Vidian canal, and pt*'rygo-palaliue eiinid (in tlie i*nlpr named, from 
oIhivc and without, downwaixi and inward.l The fns«i ciintnin.* McHikol's gan- 
);1ii>ti, with its nioU and branches, and the terminal brunches of the internal 
maxillnry artery enclosed in a mass of fat. 

The lalcnil region present': postcro-inferiorly the eslernal auditory metitU!*, 
uwirly ill tin- same vertiMl tninsverno plane with the breguia, anil behind this 
ihfi iniL'^toid procow, with the variable mastoid foramen behind and above il. 



■■Men ■■ o«TM 



inruHoiauLUH 

CHI* li4L CAn 




CITtHKll. ftUBI- 

■ ABTCIQ J 



Fio. S«.— Ttw ftony ■tnoiK* of tbc hmiL (Tola!.! 

The bas* of the skull extsmftlly (Pig. '241) from the incisor ttH'th to the 
external oniipilal protnbeninoe is verj* irregnlar, and may be utiidiwl in three 
di%'i»ioQ&. 

The anteriw or palnU- lihiiitm includes the hnrtf jKitflr, formprl by the palate 
proeoiij'eo of the iniixillie and the imlate-boni-s, and bonndetl Ulerally and in fnml 
iiy the iifn-'Jitr nivli. Mi'sialty in fronl notice the imtfrior jut/nliinr /fniMi, into 
whioh four fiir.in)in:i (»]>en, and fnnn whieli, in yonng nlinlN, the !<ulnrcse(>anitiiij,' 
the prennixilinry Ihiih- riin« to the onlrr ^ide of each lateral ineirtur tooth. At lln- 
po-rfi-rior angles an- thi> lower openinc^ of the ptalerior iiaUttioe <itniiU, fniiii laih 
nf vi'hieh a groove rnns forward in the angle l>etH'een tlie palate and the alveolar 
arch for the anterior jKilatine nerve and the posterior palatine ve-ssels. The 
hamutnr praer/eii'ii are seen at the ])Ostero-laleraI limits of Ine hard palate, behind 
and internal to the la«t molar teclli. Between these and the posterior gxtlatine 
canal are ihe oficnings of the accessory nnd external )ialatine e»nals. 

TIio iniihilf or eubcrtini'tl Hh-iirioii extends back t<ia line jiiining the tips nf ihc 
mo.-'toid prorcswes. It sIojks upward and forward from iK-hind, nnd is at a higher 
level than the anterior divtiiioii. Retween tliesL- two diviigons an> tbv followitig 
x'erlically-rilaewl structnn^s: Mesially are the jimfei-lor iiffrc", separated by the 
vomer, anil bounded l>elow bv the borixonlnl plates of the psi late-bones, laterally 
bv the internal pterygoid plates, and above by the IkhIv of the sphenoid and the 
alie of the vomer. On each wiiie t« wen the pl'-njijoiil Jh^kh, completed by the 
lubcroiity of the jHilate-bone below, and lodging the internal ptcri'goid and tensor 
pa 1 ati m nuclei. The latter muscle arises from the opfijifioiW/ofuic/, ii subdiviKinii 



S06 



THE BOXES. 



of the pterv'tfoid foiifA at its upper (Kirt. Extcrniil to the ]itvrygoi<l fbeea is tlie~ 
ti/;/omntic /rKnin. wIiuhc nx't' forms purt "f llic tmw of the :=kiill. 

The ba^iliir ppxcsj^ nt' iIk- iHripiml Ixjtic iiml n sm«l! jwrt uf tin- IkhIv cif lin- 
Bphenoid ("Cfiipv the mnVmn jiuriwn of llii- tiiidillf ilivUiiiii. wliili" lnlr-ruHi/ tiTV 
tiic p«troKiI« mill Kmiill p'lriions of the ^rt-nt wingH of t\w »iphi-iiiiiil, of llic Mjiut- 
nio!<iIs, niul of llii- iHvipital hontt. lu tlie median line we iioiict- tlx- phtiyi/Dff^til 
tuhfi-rlf am\ tlio aiittrior uinrj^in of the: /oramm mnjftum, termed tin; liiwitm. IjiI- 
uniUy, w<' iiotici- Ciorii before liaL-kward, in a nearly .-^eitlal line, ilie/owimrt» ornlf, 
the /ririww.u K/iiiKiHum, the opening of ihe bony portion and the groove for ti»e 
oartilagi»i>ii»> [virtion of the Eustaeliiaii i-atial, tJie entrauoe of the carotid eanal^ 



Tint ro»»» 




PALATE Dj«l«IOH 



[•uacKiHiaL 
eivimiOH 



•TVlO-HnaTOIC, 
(ORHMtxi 



DIVKION 



7io, 2(L— Dnc flf Ui* tkull. rlc««4 from brtow. the minillhlc htrlnc bttii ronoTed. (TMtui.) 

and l\u- ju[;iiliir faiwt and t'orninai. Intt-rual to llic l;ilttT i(* themifc.wr rfmrtif/ar 
/ornmeii, iind c.vtcrnany the Ktylo-mnxtoiil foravicn. Betwecii tile extrcniiiy of the- 
petroUH ]>onion of llio tcmpornl hone, the basilar process of the oc(<i)itlal atid 
ihe sphenoid, we notiw the Jommm larrmm imdhrm. filled l)y Dhro-airtila^ in 
the recent stiitc. In an oblique line from the mantoid proccpw to the eKtonml 
ptxfrygoid pliili' Ml- find projpctinp the ttyhitt profou, llie vifjlnnl procetti' of ih<« 
tympanic l>one, and the Muiur iif tf,r Kphrnoi'i, tne latler Hi the inner end of the 
GlaMTiaa fissure. On rlii* .■(nrfiin- i* wen hiterallv the rminmlla n rfimturis in 
front of the articular part uf \\\e <i(en<ild fnum, which n^ w[^mrted bv the G/am-rian 
Ji»»urr from tlic non-articiilar [jortion on llie outer surface of the tympHnic plate^ 




THE EXTEBIOB OF THE SKULU 



307 



which 1o<l)i:«)i the jimrotid glnml. Tlif tine limitiiifr lliis n-frinn Ix-him) ]>as.4eA 
thnnigh the jupntar prwwsvs of the oociitiUtl iwiif, iiinl cuU llie itin<iyIe-> a little 
bchitxi tlicir cviitrv. 

TIr" fiwttritjr or laJtoccinittd diviiawi ext4^n(l4 Iwck lo the superior riirveJ lines 
of the occipitnl Imii*!, diviaed into two latt^ral tialvea by the external occipital 
crwt. It incIiMlpx, mainly, rough lines and inlerv«nine spaces for muscular 
atlnchni<-iil. lichind the condyles are the pogia-hr coudtflar /osacp and /oramina 
whi-n tht- latter are prpsenl. Internal to and slightly W^hind the niar^tuid pr(>ci-«»e» 
an- the di^stric and occlpiial j^roovet, for the digastric miBck's and the occipital 
arteries respectively. 










no. M2— Front view nf (he ik 



ibl« hsrinc b«cii remoTCil. rTcMiM.) 



TIk- »nteriOT or &clal region (Fig, 242) pn^pcnts the nrwion, in the centre of 
thf njL-40- frontal Mnliirc, WIow tht- ^lalx-lln. B<-low ihe tiU:jion i* the prominent 
briilift of thr none, formed by ihe na-^l honcM hikI the tub>al pruccSM-s of l)u> 
ntnxillte. Bolow this U lite anttrior na«iil o/ja-fun*, \vhicti is fhniKil like an 
inverted heart and is often nnHymmetrienl. Itit thin marjpntt nltncli tlie nawnl 
cartilages, and it* lower horder projeeta forward as the on (or iV»- natal apinr. In rlic 
recent state it is bisected hy the septal cartilages, Ilelow this, on eitHer side, are 
the incienr fijssBi. On either si<le of the hridj:e of the no>t» art? the orbit*, below 
which arc the canine Jovtur, and external to the latter the proniinenoes of the 
diecks, formed hy the malar Itones. The teeth are a prominent f<-ature of tJiis 
Df^oD, And below them the body of tlie lower jaw completes the anterior surface. 
TliL* tlirce larpv /owminrt, atipraorhiM. infraorbitaf, and menial, each for a branch 
iif one of tlw; three divisions of the fifth nerve, lie in a nwirly vertical line drawn 
thronj^i the wi-ynd lower bicuspid toolh or the inlervid Im-Iwi-ch ihe two lower 
bieitspids. The «nnll miliar ctiiml is "iiuatcd more liitentlly on the mnlur Iwinc. 

The OTbita an- two irregiilnriy ({tiadrihitcnil, pyr.iniidal fiiswe whit^h liKigi- the 
eyeballs and thi-ir ninM-U-!v, nerves, and vessttls. Tht; bane of each, directed for- 
wanl and »ilightly ontward, i» formed by tin- orbUnl moiy/n, whidi is qtuidri lateral 
in »huptr with n>nndi-d inigli-^. It i» humidid nbovo hy tin- frontul, with the 
BUpraorbital notch nr fi<nimt-n at the jnneiinn of its inner and niitltlk- thirdit; 
int4.*rnally l>v the na.-Mil process of the maxilla ; helow bv the infraorbital mui^in» 
of the maxilla iin<l malar, an<l externally by the mulur l>one. The cnncavt- rtiof 
of each orbit is formed by the orbital plate of the frontal and the small wing of 



306 



THE BOXES. 



tlio KpliciKikl, Thp mder v^nlU nf tin- <irljil> ilivci^i' so ii« Id Ik' iilniuiit ;)( rtg 
audits witli cucli ntlHT, mill .-irt- liirincd \i\- llic inhiliil siirraci'-H of (lie pntit wiiips 
of liir s|ilii-iii)i<l iirul till- niiiliir lHJiir>, the hilti-r i'i>niaii)iiij; the t<'tii[H>rul und 
iiiiiliir (V-iiihIh. 'Y\n- fiour, nliniiiit; fnnu wiliiiii ilowuwjinl and (nitward, is formed 
liy the mnxitla, willi tiu- oriiiUil jintri-ss uf the jtalate-bone lichind and ii Ktnall 
part of ihe miiliir lioiie in front. The invtr u-nUn of the two t-avitii's are m«rly 
]inrallel, aiwl arc .-o continuous with the floors as to )five a triangular shape to the 
orbit in some specimens, whieh is especially marked at birth, Kach is tormed, 
fmm before iMiekward, hy the nasal process of the inaxillu, the Ifiehrymal bane, 
the OS planum of the ethmoid, and tlie body of the f-phenuid. The apcjr of the 
orbit is at the inner extremity of the sphenoidal fiwiure, whose outer end separates 
the back part of the roof and outer wall. The updc jornwni lies at the back of 
llic orbital roof, above jind intermil to the ajjex. Iii the suikIc between the roof 
and the inner wall lie the anterior and jwsterior cthiiioidid foraniinii in the eth- 
moidal seclii'ii of the i>-aii*ver*e nuturi^. The latter extends horizontally between 
the external ant;ular processes of the frontal bone, alone the margins of the 
orbital plates and the nib^al noteh of the frontal. In the angle between the 
roof and the outer wall, in front, is the /o«sa for tlir Uicfiri/niai ybinii. In (h« 
angle botwt-en (tic outer wall and the floor in its posterior two-thirdu i« thwl 
fpheno-nrnxUlary fiwurc, eommunicating behind with the i-pheno-maxillari.' fo^ia, 
and in front with the zyRoniatie fa«Ki. From its inner border the infraorbital 
f/roovi- passes forwiinl in the floor of the orbit to the injrrwrbilul rannf. In the 
angle between the floor and the inner wall, and jii^t behind the orbital margin, 
the laehriiwitl gro-re piiy^es down into the Inrhnnmif riniitl. A «leprc.-^ion, some- 
times a tubercle, for the ]>iilley of the Mijicrior oi)Uiine nmwle i» tui^-n n littk' 
behind the isiipcnMtitcnml angle of tin' orbital margin. The orbll.'^ c<>niiniinieat<> 
with the cranial eiivilv and the na.-^d, ^pheno-ma\illai'v, and /vgomiitie fo^<itr. 

The na,sal foass (Fig. 24.1) an- iwo irregular, oiiloiig eavitiis of a iruncated 
pyramidal sham'. They are narrow iniUNversely, e-peeinlly alMive, but have a 
eoiifiiderahle diameter vertically and from iK-forc hnckward. Thev extend from 
the base of (lie i^kuU to the upiK-r surface of the liaiii palaie, anif open iii front 
by the itnicrior nasal ii[ierturc, and beliind Into ihe pharynx hy tite [>oslerinr 
niirc». Tliey are situated one on each side of a median, vertical eepium ntm or 
intemnl trail, fonued by the vertical plate of the ethmoid, the vomer, the rostrum 
of tho .■•pheiioid, eIu- nasal .-pint- of (lie frontal, and the cre;^ts of the nafial, niox- 




Ptii. 3VS.— Th* uiwl totmr. Tic 



ino o* Hill- 



.-.ue. nVllnt.) 



illary, and mlatc bones. The angular interi.-al in fnwit between the vomer und 
the ethtniiiil plate is filled by tJic septal cartilage, which with the bony ceplum i» 



THE INTERIOR OF THE CRAXIUAf. 



209 



ttsuallj' dcftpt^ntl to (mc»i<K', iinwt coidiiioiiIv to ilii? Iff). Thi- idrrnvr rixi/'of mcli 
fo^»a hn» It tiiiififlc /utrUuiilii/ jMiii tiiriiK-tl )iv 1)h- ■■rilintonii jihiii' ol' rlit- (-tliiiutirl, 
with itH niiiiiv iiiiiull it|n'r(iir(-n Uwliii^ front iIk' imtcrixr cnitiiul i'".<-<i, iiml nii 
■iiti^-rior mill ii [Kwieriiir iwri .-liming ilownwanl. Tin- luitirior sIojhi i^ roriiK'd 
by the iui.-«il bi>n»?N iind the iia«il spine ol* liie froniul. Tlio pitiiterior !-Us\n- u 
rurnii^l Uv lite budy <it" tlie t^pht-'iKwl nml the hplwmiidal tiirbiniitc boiit:-, iind 
ci)ii(aitL-> (lie o|jeuiiigs of the sphenoidal wniijH-'p. Thv floor of each fossa, wi«hT 
than iht" n>if, is siiioiith iind rancfive (rjiiiyv<'rM.'Iy. with n t^li^hl barkwaifl sUiih*. 
It is rormi.t) hv the ))alut<' pr<xv)^fr<-!i of thv ninxiitu iiikI puliiti.'-1ii>ii<', nixl presents 
in frvHit, cliwe t'r the «'ptiim, iIk- I'nwVir /wcdmrH (nr •■fiimf), Iriiilinj; U> the oral 
cavity. The extensive outrr trull, sloped <l<nviiwunl imd outward, is loniied hy 
tiie Dnsal, iitaxillarr, luchrymul, (-ihnioid, inferior Inrliinntc, urn) pahitc- bnites, und 
the inner snrfaco of the inCeniiil pleryguid ])lale. It prej*»tJ^ thivc Iiori;:oiital 
recess^ or mf^ttwn, nverhnni; hy (hrtfo lurhiniiU. phlm, of which ihc Hp]x-r two 
belouji to the ethnioiii, iinil ihr lower is the inferior lurlitniitc hone. 

The iiitftrrini- iiiniluK, Ix^ween th« wnjx'riiir nnd iiil<-ri<ir Inrhiiiiitr ]ilute» of tho 
ethmoid (^^niienor :ind middle tnrhiniile hi>iM''>), in verv nhoh, heiiij^ limited to the 
posterior half of the fosMH. It o(nii'< licliiiul only, tind into it o|hii the poj'terior 
ctlinioidal ix-IU nn<I the :>ph<-iio-i>uliitine foramen, wliieh oonncHi» it with the 
;iphemr-niuxill»n- fo^sii, Tlio mitldU tnrxitiiM, hctween the inferior ttir)>itin1e ptiito 
of thtr elhmiiid (niidilli- liirhinnle bone), and the inferior tnrhiiiiitc heme, i- li<n):<T 
lliiin the former. It open« both in fi-ont nnd behind, nnd into it open the muxillury 
iiinnn or antrum, and, by meuns of (he infiiiulihnlnm. the fi-onlal sinii? and the 
anterior ethmoidal <;e!ls, Ilie inferior vuoiiig, the longest and widest, als« ojhus 
both in from and behind, and lien between tlie inferior turbinate bone and iho 
floor of ibo nasal r»;sa. The niL-<ni duct oncns into it superiorly in front and 
connects it with the orbit. The iia>^l fossie lliiif. coniniiiinoate by narrow [ishMiiies 
with all the neigh bur inj; fonste ami air-sinnses. The latter are hollow spaces 
within the maxilla, sphenoid, ethmoid, nnd frontal, already de.->eril>ed in eonm-ction 
with those bones. With the exception of the nnirnni, which exists during; fo?tnI 
life, they originate during childhood, and all increase in ei» rapidly at piibertj-, 
and more slowly throughout adult life. 



The Interior of the Cranium. 

In a skull biseeiiii honzt^ntally or vcrtieally notice the preal proiiortionate 
ri» of the bntin-Ciiviiy an<l the ihlekne-s nn<l eonipo-iiion of its viUm (rig. 244). 
The latter consists of iin ouffr and an inner tabfe of compact Iwine and the inter- 
vening cancellous liipltiS (" fold "). The iiiurr Uihlt-, called ihe ritr'-num tatlr from 
its hardness and bnttleness, has a smooth, shining surface, marked with impres- 
sions for the convolutions of the brain and wiih grtHnes ior bl<HKl-ve>isels. The 
»kiill-e^p or c<(/r(//(V( averages one-6Ah of an inch in thieknes*, but along certain 
ridg<.'*, and espo.'ially iit the base, the thickness is nmeh greater. Thinner areas 
exist in llie erd*riform plate of the ethmoid and the orbital pliileis of itie frontal 
bone, where there ie no diploe, and also In the lower oeeipitul fo^Ktr, and the 
W|iiumoTis [lortiims and glenoid fossse of the temporsti Iwnes. 

The c^Tarla or aknll-cap consistii of a vaulted dome,^f<!rin(Kl by the fronlnl 
and piirieud hime^ and the inter|i:iriet»1 portion of the occipital bone. It^ inner 
Murfact" prt'senis in the m"lian line the ijrtmrr for the miprrhr /•iiii/!liuliiiiil kiiiii*^ 
ending in front on Ihe frfinhif. i-rrid, and bi-litnd at ihe intmial rn-rij/iUil jirvtti/m-~ 
nniv. On either sifie of the gnwve nre varying numbers of ilijir^nnioiiH for I'm— 
rhioniatt liodieg. Tin* *tirfaee it markol by shallow eerebral impressions and 
grooves for meningeal vessel.*. The jutritinl foraiufii, for an emissary vein, ia 
found, when present, at the si<le of the hingitudinal groove near the poslero- 
superior angle of the parietal bone. 

The baM or floor of the cranial cavity (Fig. 245) ftroreots three irregular fo««e, 
termed anterior, middle, and posterior. 

14 



210 



THE BOXES. 



'V\\e anterior J aioin, n» a liidluT k-vol I'laii llic rest of r)ii^ cranial fliK>r, supnorw] 
the frontal loltes of i\w cph'linim, am] in Corriiw] Iiv ilie orliita) jilaies of ihti 
fri>nta) lioiic, tht tribnl'iirm )>lai<- of tbi' I'lliniokl, aiul ilie linuill wings ami mrt 
of iliG Ijodv of ilio -plicnoii). Ovrr ilic orbits ii i^t <^onvex, but niL'sially ii is 
ilcpresst'tl iiilo tht' olfactory yroovc-^j for the olfartorv biilb^ nit either siOi' of the 
crista ^illi. In fn)»t of ihi- crista if thi- funimen iwciini. Tbo floor of the 
olfactory groove;? priscnts niimiTniw u]N'rtnrfK In ilie cribrifbrni platt- for ihe 
olfiK'tory norvi-s, inci^iiiliy llii- »lil-likc fniiiiiicn Thr<>ii)!ii which the na«il i»cr%f 
ini'^K'K into itic iv*r-t; ami laicrally llir inlt^riial o[H'nin^s of ihc anterior and 
IMisli-riiir I'thnioiihil canals. 

Thi' ini'!<llrj'/iw,i,iiu n hiwer level llinn thiranti^nor, jinvvnls n cent ml ifllimus 
and t»o lali-i-jil ih'jiri'.vcil fuirls. The .imall nif^llan |iiiri Ik liniik'il iM'himl by the 
<l(ir!<nm m-IIic, anil in front by tlio antL-rior margin uf ihi- rt|iti(' (groove. ]l liKlg<-!i 
the. [)iluitary bndy and the optic comtuWure, ami preaenm laterally th<- groovt-s 




■AXUN 



eoHOVkc 



__ Pie /U.~«wt>t«l necilnn of tkuU. a Hnlv (o ih« IcR nf lh« ii>lil<l]« Itiip, ihi- liinrrturlhp* at tit* Hsht lull 

for th<- csinjtid arl«ric<: from the for.iniina lacera media forward to the optic 
fiiraininn. Tlic iad-nil [uul on each side it- limited behind by the ^n]lerio^ boixlor 
of lln' jK-troiH porlinii of the tempoml bone, and in front by tin- fret- nmrKin of 
the small wing of llio splicnotd. It is formed bv the jjreat wing of l!ii' sphenoid 
and the sipiamons portion unci the iiiUerior Mirfaee of ihc iH-troiiK portion of the 
temporal. It IihI;;!-.-. llic icniporal bil"- «f the (irebrnm, ami pn-H-nt- the following 
foramina from bet''ri- Unkwanl: the Kj,lir-ii'>iihl lixmirr h-nihni; into the orbil ; tin* 
fnramrii rnUimliim. h-ndini; into tin- >pb('no-niiixi!]:iry f^^■^l; i\n- /oriimen orn/c and 
they"'-'iHwii*ryi(iiiwtt(m, leading into ihc xypimjilic fn-^-ui ; \iiff>iniiiini hefrum mrdiutu, 
tlintngh which the carotid artery and plexns enter tin- er.inial eavity ; and ihe 
huttm Faihjfii. Grooves for the middle menin^al arterv pass from the foramen 
Kpiii»iimi ontwani. npward, and baokxvanl on the great wing of the Kplieuoid, the 
.<i|niimoiH jw)rtion of the tem|»oral. and the parietal bt>ne. 

The jirwfrrii}!- fnnMi. the deeiM-st and lai^-si, toilgcs llie cerebellum, mednlla 
oblongata, anil jw)n'. and i>- formed by the occipital bone, the petrouK and niii>'toid 
portion,* of the lein|w>nil. the p'l^ter•^-illfeI^or angle of tlic |Ninctal, and (he b<Kly 
of the Hphenoiil, It-f anterior liniit« are the piMitenor limits of the middle fosM, 



I 



L 



Tin: IXTEIUOU OF THE VHAXICM. 



211 



and iis [Mwltrior limit? tlie j;ri>ovcs for ilic lateral .'■inii^'s nhifsc Hmiiiii^ ridgiT' 
^w miaclinteiil to x\iv ti'iiluriiiiii cL-rt'lji-lli. 'V\\o jurtnunt ui'ir/tw.m (M'ciii)iu.'i llie 
centre, and i-xti-nml tu it from ^vi(llill uiilward are lieeu i\k anterior nimiif/ar j'ora- 
meii, liie jutjuhir /"rumm, luiil tlif itUrrnaJ andiloty mctitu*. licliiiMl ibe jiigiiUir 
ri>mm«n ifi the upeiiiti)^ iit* tlic /Kuitcriitr cvMtlybir Joi-amm ulieti present, and more 
estcniullv, in the "igMHtifi "iilciii', !k tin* more cuii»tunt mtiftouf foramen. The 
griHJVe* for the luter.il simiM-* |iuw oiilwiinl fiimi tin- iiit<-ri>:il '>c'(-i|iitfll jirottilK-r- 
anee, iixnully vT»<f t\f |i' wifrior iiitirior ati}:!^ ol' tin- ininVtiil Imiic, und iheiiee 
bcml Mtiiioii»lv <l<>»'ii«'iirtl am) inward on tliv nini>I<>i<l purtici) <■!' (lie temporal 
Ixinc.iind oiil« die <«'i>ipital Unnc, whi-rt' ih»>j' ctin-c lorwanl and t-nil at the yoifiv- 




Fw. My—Btrnt of IliD cnuilum, luiwr tutiko*. {TMtutJ 



rior diviMon of the Jngninr foramina. The grooves for tJie inftrior iKtrosal 
finuMW lie alon^ the suture lictween the [>etnm-< portion of the lempoi^l byiic and 
the iHY'ipituI, and end in the nnii'n<ir tUvii^ion of the jii^nlur fiiniminn. Ttx- 
juf/ufar Jornmnt (foraitu-i) lacfniisi jMisteriiifi) is nsnally ninvnitnetrieiil on lh<' two 
sideH and of a f^miewhat |»yrif(irm cliiipt-. It ii- often diviileil inln tiiri'i- eoni- 
lairtiiK'tito liy two nuiiv nr !es- markeii eon(itrielion>'. Throiit^h llii- liii>;i'7't and 
iiiiwt iumterior of the*' the lateral hinii" p!i»i«t'i' into iht- internal jii);nliir vein, ami 
a .'•nuill nx-ainceal hmneh of the aw^'iidine phiirynKi-ul artery aKeemlf; iln" middle 
eom|Kinnu'ni tmni-niiis the (rl<*&*"-ph!iri-iiip-jii. vaga*, and spinal aeeessory ner^'es, 
and the nni«ri<>r (iwnietimes eompletcly «e|nimt<Hl) tmnxniili* ihi- inferior petrowl 
NiniL'». 




212 



THE BON EH. 



Oeaeral Morphology of the Skall. 



The rniniiil nerve* jisisB through the i^kull in t'limminii oeciipyinff «ilt 
i nil u'uti 11)1 jioiuts ul' tiinoii <jf' two ur more o.-«i6e eeiitiv>. Tin- Corttmi-ii 



wiitiirps or 
minn- 
dtiin iii the unly execplioii to this rule in (he i^knll, and thiii \n pn)l)al>ly u «f)>«Rited 
sedtiieiit of thi- K]>h('iiiii(hil fiHiHiiri'. The division into primary foramitm, or ihort- 
wiiere the ncrvojt [>rt.-w ihmugh tiio diini (or origiiiiil bruin -cane I, and .■«r<'iiwl- 
ary fnniiiitii:i, whit-h uip hniiy tiniiiels nr mniiU not fouud in f-tninlcr skulls, 
tlioiifjii itit(ri'Mliiig, is ncil of Niillieicrit importanw for further dcM-nption here. 
The reiiiiirl<ul)!i' i-niistinicy uf l!ic ninticm nf the nerve foraniiiiti to the osseous 
olementf has, with other fail^, Icii to llic (■oiieei)fion of the verlcbrale iheorv of 
till.' skull, which sii])iiiiM-!* that tht- >knll i» nmdv nji of ii nerie? of altered vertpline, 
ihc neural arehc-1 of whifh have bccnnw! (;rnitiy eX|Munl<t[ to eiieloM' the brain. 
AnnMig iJie Gicta leading (o this th<«rv >-■* lh« uyiiiirmt runittnii-finu nf tin- nhitl in 
llinf fjiiiin: 1, the cni/'vi/ or bii»U(ir, |ii'oloiigliif>; forward llie verleliral QXia 
aroiintl and beyond the end of the notiH'hoiil in liii- vfUimi-juciiil axi«^ : 2, ihe 

miprrior hivAcji, three * in number, enelowin^ the hraiii ; :t, i (jUiil iiuinlx-r of 

iii/rrhr ai-chre* <-urroutrding the viheend eavily, a.- n-im-x-iited by ttw- no»4', 
mouth, and pharynx. But, although from analo^v we may imagine that the 
prindtivc human skull wits st'gmentvd itke the verteftnl axix. theiv i^ no cviilemi- 
of this, and for a nninber of other ivasoii^ Uie divi-ioii of the head into vi-rtehral 
segments i* nntrnftworiby an<1 fatii-ifiil. 

In tlip tliTrlojiinriil nj flu- nkull three stages may lie rcw^nlzed : I, the mextt- 
bninoHg iOii/r, in wtiicii the bniiti is enditw^-d tti a nienibr:me n-nret^etiting the 
duni of the adidt ; 2, tiie cluDulnd Ktiuft; in nliich the baw and lower parts of 
the itidw of tin; bniiii-ea.HO iH-nonie »irtilat:inoni^, Icjiving the Hden und niof mem- 
bra non« ; -3, the (ixiifoitti i^iif/i', in wliti'li lioth rarlJInge ami nienibrinK' beoome 
OssiRod fr<im a lai-ge uninlier of n-.-iiie ifnlri-s, whieb tirft appi-ar in the nieni- 
bntrie. Alonp the sides and in fmiit Mni'e-eapsiilis lieeome invaginated. and 
indent the skidl-wiil! iti (he eai^, eves, iind iicim-. iSnne of t)ie Ixiiie-^ of the skidl 
are dc-viOopcd wholly, others parily, in the liiisal nirtilrtire and its forwanl iiro- 
hingiition, the? eartilaginons nasal eaiisnie, or In tiie citrtJIiiginoiis viM-enil an^m^ ; 
whih- some an? dovelojMMl whoilv, others jiiirtly, in the membraiii- of iho oranial 
vault, in that around the nasal eaiisnle (fiirniing (he gnaiter ]»art of tin- u}i|H-r 
faee), and in that eonneeted with the viseeial aiilies. 

The kiimiin xhill, as eoniiiarcd \iitli the -knils of lower vertebrates, is eharao- 
terixed by — 1, its enormous ln-.iin-spaee and the eon-esiuinding exjMinsion of ihe 
bones of the ernnial vault ; 1, the pro|iortioniilly smaller development of (he faee, 
and espeially of the jawrt (bringing the iiiee under the front of the cniniuin); 
3, itji beinu; Iralinceil and -upiHirted on the vertebral eolumn (iiduptiiig it to the 
erwt position) by a i^udilen bend in the vertebro-cranial axis, and !i great posterior 
development of the ciimium, bringing the ocei pi to- vertebra I arliciilalion at the 
centre of gravity of the -kiill ; I, (he downward ojieniug "f ihe no>trils ami 
the diminii'lied i-tze of the nasal fiw*»'. bringing the orbits nearer together, so xa^ 
to be nearly parallel ititernatly anil to look forvranl. The Immk-k of the linman 
nknll are more eomjiletclv wmsolidated, »i> that the t'ltal nnniber is li'>« than in 
the lower verlelii-ate-. Tims (lie pn- anil pi)M-si)lienciiils. ihe interniirielals, tlwf 
iUjliamosill^, the styloids, tlte pterygiiids, and (he imniaxilhe are often si'imrnte 
bonen, and the fnnital lx>tie and mandible are frennently divided into two nalvi-H 
in vertobrute skiiUn. 

' Tliin ia drnwa from ihr tiuiiiiin U> ihc uiiiiTior cxtrMnity tti Ihe ii|th«naid, mid lh«nc« to (be vaA 
of l)iv Hiil^rior tiu-^h] t«]}|tii> (HiihiiHMiil (X^intk f'lmiini^ jin :iiiLfli*. lilt* fniuia-/'tfittl iiiujU. 

' ThRv conuKt uf— 1. tliv MitiHiu<Bal (iKrl rir tiie uecit^ilul bom- : '£, llie Kmit uiiiics of llie >pbp- 
nniil, till' wfiinniimli of (lie lemporal bann^ nad ilie piirirtiils ; A, the small witiev nf tliv iphenotd 
anil llu- fti'iiriil Ikiii*. 

* Thrw includv in lilt' lint no'li (lie elen KiiUlx, tin- jmlHtr. unil Oiv iiniiillHiY twiipn: in lli« 
•(voncl. till' inaiidibli;, ihc icpht-no-mnndilnilar li^iiirnl. and the mnltcuH of tin- car; In ihe Ihird, 
llie Htybiil iinii'p-xi. i)i« liyiuil bciiw, and llir rtf lo-li,void lijnmcntis pliu the Jncu*, and perhaps part 
af the mullvus nt the ear. 



4 



4 



THE VARIOUS fORMS OF THE KKVLL. 



213 



The Various Forms of the Skull. 



Thi" iJrw// til birth 'i* fltiinH'li-riwxl Uv tlip hinall hize of the faof awl the very 
larpo size of the rnmiinn, tin- t^niiilluens <»f the \y»>^p, (lie pnimint'iioc of the 
{Ktriclal ami frontal «'min<'npc«, the ahwiicp of the ruaflutil pnircw^^'*, iht- iliploe, 
ihe buiurc wntitioii", the impn'>.vion«, gnnivps, ami rHlprj*. uiiil 1>y the fxi*«'iice 
of tlie funtatK-tkw. The h-iiijHintl x|immH ;iimI Ihv ^n-iil winjpi of llic i'|ihvmiiil 
do not cxtomi far npwunl, uiiil ihi- gU-noKl fi)vsn' ni\' '[tiiti' flnl mul Kiimil, 

Vnrinliotw irllh Affi: — Th** .■•kiill nmws vt-rv iiijikIIv iliiriii^ iho firsl »i.-veti 
vear*. Ihirintj Ihr find ilmtitum the fimtmiHIcn cIim', (hi- Ikoi- oiilai^.H, thi* javrx 
leii)^)irii, Biwi the JLVfjuriiji prxjeots. Hif Ihr m^venlli gmr rianw parts, such its llip 
irirpiimfoivMO)' of ihi' fimirm-ii magnum, ihi? j>t-tn>us tHirrtoii f.f thf ii"iiinr>ral I>oiim, 
lh<- bwHv of the sphenoid, ami the mbifurm |ilate, have atlnimHl their definitive 
«W, while other jmUs hk oilite immatiiPe, Srar Ihr tivpruuch rif mihetiy & 
M-c-ontl |>eriod of active irrowtn begins, and reinlt.'s in the (-limf^tion of llie face, 
due to the increaAe<l height of the misid fowa, the expansion of the air-siniises, 
liie enlaiywl teeth of llie jieeond dentition, and the aiicmcnied lieiylit of the 
alveolar arclie:^ of the jawfi. OwifiKition lu'cnmes ci)nip1ele<l, uiid the adtdt >iliapc 
and «w> an' attaim^l. The capacity of the cranitnn increiiM^ Init little after 
thirteen years of ajre. In Inter t/earH the inuaciilar eri'sis develop, the fi-ontal 
region elongates, and the air-]Htssagesand cells ex|iand. itie latter process continu- 
ing in old ajte. In ofil aijf the sltnll undcrpoc«t atrophy, lM>coi!iin^ thinner, lighter, 
and ot'ten a little Ainaller by absorption on llic outer snrince. The air-cells ex|Hin(l 
as the cajKicitv diminishes, tlic (ai'c Ix'coines <:iuallcr by absor|>lt<)n of the alvcnliir 
prwccsses and the loss f>f the Iccth, and llio increiiw of the angle causcH the lower 
jaw to project at the chin. 

Sexual VariatioM. — The m»/r nhiU is hirjier. heavier, and of grvater capacity 
(11 : 10), especially in the fnmtiil and occi|iital regions, than the female, and the 
ridgiw, oecipital protuberance, nia>tnid oroces-es, xyjiomatic arches, and frontal 
uniL-ies are more dcvelopcil. The {nnatr nkitU pn-servi". a Iwik of immaturity in 
the smaller proportion of tlic face, the narrower and less prominent jaws, the 
pRHninence of the {mrictal eminences, and the smoothness of the surface. 

Race difereneex, except umong three or more Inrge p.'ncral chis^if, arc often 

so slight, taking averagts, as to require acciinite and uniform riiinial mciisiirc- 

meni or ciTtniometry for their dctiTmiriMti'in. Of the meafunnu'nis the most 

im|>ortant are the following, widi tin- <\\\[n of the iivi-iiigc Knri>|Kiin sl;iill!i for 

each : (1) The <'U}»ieilg, H'lO v.v., iilloriiiiig ii eouvciiienl inilinilion ol' flic dcvel- 

opmpnl of the l>rain. (2) The inrmimjrrenvr, 52 em., taken in n plane panning 

Itcliind thriMigh the oerifiitit/ puini (or llie point of llie iHripitiil l)on<- in the 

niixliun jiluw* farthi^t ivmoved fivim the glaliellu), and in fiiHit ihroiigb the 

iffArwoH lor the middle of the line drawn airoM the inirrowi?<t pari of ihe fori'- 

beai^. (-S) The leuyth. 17 em., from llie ojihryon to the (H-eipitul point. Tins 

is alH>vi' the fiimtal siiins, and gives the length of the brain-<-ant.- only, while the 

iwtxltHUUt IfM/th is between the glabella and the occipital j>oint, (4i The maxi- 

niMu< breadth is the greatest breadth between the parietals ; the hn'adih at the 

level of the i-ygoraata is 12.-5 cm. (o) Tiie heii/hl fnini the busioii to tlie bregma 

i.-. nearlv the simie a.« the bn-adth. The cranio-fitiutil um/lc is abont HIJ". For 

the ready comjiari^on of Ric<--inca.*nr''nn'nt'' the hreiwUh and height an- n-ihieed 

.... . „ „ 10" ^ breiHllh or height 
In tiuliixes by comparison with the length a.-, follows: r —rr • 

Furtlicrmore, the shape of llie tnuisverse areli of the cniniuni, the I'nsion or 
complexity of the cutiire»(, tin- ilcgree of projection of the jaws |indic!tttng an 
approach to, or u removal from, ihi- nniimi) ty(H'), the relation between the height 
and the width of the niiterior nasal :i|KTtnre (or nawd index), ami of tlie hose 
of the orlfil.s (or orbital index), an- T-nbjeil to varliition nio'ing (fillereiil niccs, 
Tbc Jufifil anijl* (of Chnpit-t |, which hel[>s to dtvtcrmine llie rcluiive developineiit 
of the bee and the tronlal [tarl of the eranium, is that tbrined by two linm 




214 THE BONES. 

meeting in the median line at the alveolar border of tlie maxilla, and drawn, one 
from the most prominent median frontal point and the other from the middle of 
the external auditory meatus. Several other meaHiiremeotH for more accurate 
determination of the form of the craninm are in nae, for which Broca'n or other 
worke on cniniology should be cousulted. 

The itUualion and directum of the Joramcti. magnum differ greatly in man and 
the lower animalu, and to some extent among the different races of man. In 
quadrupeds it is placed dorsally and looks rackward, in man at or near the 
centre of the base, and looks downward and slightly forward in the European, 
downward and slightly backward in the nt^ro ; while in the anthropoid apes it 
iH intermediate in position and direction as compared with that in man and the 
quadrupeds. 

The most frequent irr^uianiy of Jorm is want of eymmetry, which is usually 
present to a Hlight d^ree. Asymmetry usually do]x:naH upon premature synos- 
tosis or closure of one or more sutures, preventing growth in a direction at ri^t 
angles to the line of that suture, and tending to increase the growth in other 
directions. Artificial pressure apnlied in early life may also cause irr^ularity 
of form, as seen in the case of tac Flat^headed Indians. 



THE ARTICULATIONS. 



Bv GEOiUJE W(X)LSEY. 



THE arlieutatiotta, or joinU, are the coiinoctioiiH existms between L-oiiti^ioiix 
partfi of tho n-cftu liiinmn ekeloton. Softer tiub^laiici-)) intervi'iiv between the 
ftuU of thr iKtni^it, itid a lil>n»iu c»|Mik>, with or williont accowMtn- iigaaipnt», 
biiiiU tlii'iii I'liri-tbcr. 

Tin- ariifiibir .iiirthit-, i>r i-mls nf ihi- bones, u'bicb nm- cxiiiiikIi-iI in the im'V 
of loiiji: iHiiie^, ari' iiiatnl bv a liiy«-r of i^>niKvtivi' ti.i-tic, i>r iiviiliiic, or wbitw 
fibro-cariibiffe. When )iyuUii« cartilage i> prfscnt an nrliruliu- tvirlUnif, \U( 
free tiurfaoes are Vf rv imitwth, so m to minimix« friotiuii, and it sen'os to ilimin* 
i-h jars by its plasticity. It i» tliickert wbere the ]ire!wiire is the jtroati'-'<t. 
The white Bbr(>-«iriibi)(p oocurs as ronttrcHni/ fih>-o-rtiilitiif/<r in the dlfpfi betwt-eii 
the vcrt4'l)rie and In the sym])bvi.is piilMK ; as inlfrnfiifuhir rif>ro-varlU<Tyf in tl» 
{tlatex in the tein|Mtn>-in:mdihiibir and ^icrno-rlaviniliir joinit'. and in the nienb^ci 
in tin- kn<-i'-j<>inl ; ami a;i nMiifimil Jihny-nutiliu/r in the vbouldrr an<i bi)>-joinis, 
wbi'iv it dft'iK-ns the »iKrkct». The iiili^'nirltciilur filiro-eartiliis*^ mirtly or mm- 
jih't^'ly <bvidi- tbe jnint into two halves ; tbcv udjti^t ili»«iinilar Iwnv >nrfacM>, 
inonioe the niciiion mid '•I'ciiritv, iittd iii-l a* biifli-i's to bn.-nk nbiK'k. Connective 
tiiwne exi^rn bctwii-n ciintifT'ioiis l>i>n<-!< nf tW tikilll aw luUtrt mnnhrntte. 

The tif/itmetiU. wlilcb arc the prineipn) objects of ntu<1y in this cwtion, are 
«tron}r. inextensible. bnt |itiani liiiiids of white fiUruiiM ti^ue, eMitinnoui with the 
|)c^i(II^Iennl of the bone* they unite. Tlity oceiir in tlie f'tia|H^' of a more or It** 
pi-rfeet diumlf, ifnally reinfor<»e<l wliere llienr i« tbc most strain by external 
iiprejwory iHindK or liniments derivi'<l from inlerinn!>eii]ar »e{rta, miNblie<l tendon*, 
or o-jifiywi-d nnisoIiiB. 

In joinin moviiit!' on mnnv axe.s ibo ■•ntirc I'lipKuIr- aixl ^n^^llon<lill)! inn:«-ltM 
an- nciirly nnitiirmly .■•iroii)' ; in tlioHc moving on our »\ix the biiind {iiirti> of the 
capiinio art! .-itivn^lheiiiH) and ile^Itrnateil a-* laleiiil H)riiineni.-. In .-ona- cuM-ri 
ligainentu arc fornii'd of yt-ibjw libniii.i li^^iiue, an tiic- ligumvnta siibflava, wliieli 
UDite parts not in contact. 

The deep inirfanf of the oiiprciite i* tinitl by the m/norinl mrmhranf, which 
CXtcml" to, bni not ovvr, the itrtieidiir esirtiliif^-. [n llie "liaix; of foldn or frinp>s 
it frci|uently pmji'et.-* into tin- joint -ciivity, ewiK'inally near the mai^in of tbc ear- 
tilai^', when', often [Kid<I<'<l with ftit, it fills nji tbi> iatt-i^liies helwii'n the Ikhip.-, 
Thi.* jiart of tht- membrane 1.-. highly va-->eiilar and liable to bi-eomc villous and 
pedunculated, in which eiLse it may cause (min bv betnjf pinched between the 
joint-surfaoes. It awrotiw a thiek, glairy fluid raite<l nyiinvia, which lubriealee 
the joint. The synovial eavity .sometimes conimiinieates with biir>w and vaginal 
6vnovial membranes in the nei};h1>or1)uoil of a Joint. 

Emhrt/fi/oi/ieaHfi. a joint is formed from the tissue lietwocn the ailjaeent {larts 
of the skeleton. This embryonic tih^siie may liceome the fibrous tisMie of the 
KUtnre membrane where the bones are develojKsl in niembnine, aa in nn»t of 
the Itones of the skull ; <ir it may become the thicker flbri>-<«irlila)r' of tbc inter- 
vertebml dinr^, symphysis pnbij«, ete,, when- the Imneit are develo)K-<l in carlilap^. 
A piirtial synovial membnine may occur in thiw interveninir turtilagc. In more 
movable joint» lh<- Jiynovial «ic t» inoiv exU'n.sive,and the tibro-eartilage i.s iut«r- 

2!1 



216 



TH£ AliTICULATJOXS. 



nitiL'iilar, scparatiriK t«'f> synovial sao», iw iit lln* <<terti(M-1iiviciil«r joJnl, etc 
These ))Iat«B of tibro-cartiIa^'« may tx? jHrrliirattHl, or iorm mrn'ly n menLicus, 
aitaclied to the inner siii'Iikc <if llie i-aitHiiIe, as in IIk- kiiw, or they may Ix- 
wiiitting ultogi'ther. ns in niu-it >it' ihe nuin* mnvai>le joinlri. 

Ill nccoruiinco with thix; various (lifferencc-i. artionlationH are more i>r lews 
mnvHlth'. 'i'liv ('lii-isitii-atiuM uf Joint»4 now employed in largely phyaiological, 
(Ie{H.-ii(lii>g ii])Oii liic- tlt^grei- and kind of motion. 

r Kinds of Joints. 

A. SraoTthrosu iR the primarj- form tif articulation, and includes thow immw- 
ahff joititu ( 1) in whieh the contact nf the adjacent nurfaees is prevented only by 
a thin luycr of fihrun*' tisi-tie, continiiuiiM with the |)erioKteum, a^^ in nianv of 
the Ikiik'S of the head ; iind (2| tho-i- when; bone and e!irtil:i)re are directly united, 
as iu the caj=c of (he fir^l rib and "tcrniim, etc. Kesirlv sill of th'v^ elaiw are liable 
to bony union ul difli-renl ihtiixIs in advanced life, and in early life permit inter- 
Htitiul {jn>wth. In the .-•kiill lhei*e nrtivnlatiunH nrc chIIciI *rrrfujT*i, of vrhidi we 
dii^tin^ni^h tliro^ varietic-''. 

'/i-iiK MdnrfA include Ktrml-il and itmlaln! mtirre", w here the margini* are inter- 
locked, a» in the nagittal and lanibdoid stitiin-n, n-speclively. 

Mi/«c mfitreK include fmnnonir mliu-m, when- there i!« simple np[H>^ition, aw 
between the two halves of the imlate, and mjuamoun mluren, where bevelled edgv^ 
overlap one another, as ii> the fiquaino-itarieial suture, 

<!roQv«d guiare, or itcliinr/i/lrKin, is wiiere an edpe nf one bone fitfi into a groove 
in another, as in the case of the ra^trum of the sphenoid and the vomer. 

Sunefiondro»iJ! is generally a temjionin- form of joint, where the thin layer of 
eartib^e between the lM>nes iiriually ossifies before adult life, ji« iu the union 
belwei'u the epiphysis and shitfl of long bonce, and between the r^phcnoid and 
ocdpilal buneif. 

B. Amphiarthrosis applies to joints which permit of r>li);ht movement, iind 
include «i/wi;>/iy«i«, where the (i))pi>'ied •'urfaws arc united by a disc or plate of 
white fibn>-enrtil!ipc, iw between l!ic bwli*-?; of the vertebne or the piibie l>one» ; 
and gyiuhmiQKr:', where iiii inleni.s'^-oii]< ligtiment iiuiltst the ^urfaocK, a* in tliv 
lower libto-fibnUir arlieiiljition. 

C Dia.rthroBi3 ap)ilie.s Iti the more jwrfett and uioxuble joints containing 
synovial cavities, llio (."apitiile of these joints is hni-d bv synovial membrane, 
Bcereting synovia, which serves for the lubi-icniion of the joint. The bone* 
are Iwiind t<^ethcr by libmus lij^nients, forniiii)r more or Icwi (lerfpct cjipfulei, 
which, tightened in ifonie positions of the bones, rehixod in ollwrs, are olU-n 
chieflv eontrollcrs of iiHtvcnuMit, while tin- sitrronndin^ musi-Ias, aidnl by 
atmospheric pR^SKiirc, hohl the bones together. The foUowing vanetie.s ape 
dtutinguishcd : 

.^rfiVw/io.orp/iWiV/jni'/t/j', »<lmitof but aliniiti'd amount of gliding motion, in 
one or more dinH'ttons, betwwn two nearly flat articidar siiHiie^-.-', as in the earjuis 
IIIhI tan^us, and l»et"i -eii llie articular jmKc^ses of the verlebric. 

'-Vii'/Zi/wdx, or h'lMjt-jiiitilf, allow only movements of flexion and exieluion on 
one axis, iK-twii-n the cylindrical or trochWr convex and wmwive MnrfaocH, ii* in 
the elbow and ankle. 

Oimhjhiil joint* jirei^ent spheroidal articular Hurfaces, winch allow abduction, 
tddlict.ion, and cin'ii induct ion, bi>,-<j<l(<s flexion and ftxteiisioii, tm in the metatnrjK)- 
aod metatarso-phalnnjsieal artieuUiixur. 

Siiititlf joinl* alhiw the .same motions as condyloid. The surfaces are recipro- 
cally .sa<l(llt--Hhaped ; hence they are sometimes called joint.- by nvi^roeal raxp' 
tion. The earpo- metacarpal joint of the thumb is an example. 

Jiaft-fiiirf-mciet juints [rnarf/iroi^ii) (K-rniit movement in every direction be- 
tween the splierieal Iwad uimI socket, us in ibe shoulder and hip. They are the 
most movable of joiobt. 



THE AHTICVLATIONS OF THE TRUNK AXD HEAD. 



2r 



TVyWIom/ai, diartfir(m» rotaloriit, lateral pinplifm'i*, ■>'' ftivot jf^iti ).■> ii iiiiiit 
between a pivot uiul u rinj;, as iu the mUio-utitur aiitl atluiito-iixial aniiniliilion?, 
wbirh allows only uf roUition. 

Kinds of Movement. 

Tb«> varirtiL* kintU of ruovempiit ilepoml on llie »I)a|M' of the artieiilating >iur- 
fkcvs. ami are Hoiitei) hy tlic- <-i>Tiiicctii)c; iij^stmciilA unil to a Ichh e\U-iil l)y I)h* 
t'lirroiiiidiiiK w>ft partii. The (liffcn'm Kinds of raovemeni an* often eonihiiiitl 
ami iiieryi'd into one another in uiie joint. 

liUnlioii is tile niovenH'ni of a bon<' about some lon^tuclinal axis, often it» 
own axis, without inuoh oliangc of ]i'jNitioii. 

Amjular tiwryuu-iil iiiCR'a-i-s or tlccri-a^es tlif anjjlc between (wo ImncD. Wh«n 
thi« movetuviit laUc^ plan.- around a Iniim^'erM- iixin, it is calletl flrxinu and ejtii^- 
*ton, iKX-ording iw the an^lv is dimiiiii'lu'd or iiien-iiMvl. When it taker* place 
lowHnI or from lli<' tnediiin jihint^ of the body, the iiiiddli' finger of Ihc liand, or 
the .■M-cond iiK.' of the fiioi, i( \< ciilh'd mliliu-tion and it/iitui-liiiit r^-^iioelivelv. 

t 'irriiiMilifliim is a »itinbinntion 4if ihir fimr an^niui- inovi-iiiiiil.->, so iJut (lie 
moving txme dvMrrilx^ a conf-like figure, with thv apex at the joint, the hiiiHi at 
itA distal end. 

Olidiny is the niniple-it fiirm of niovenient, and oon^^i^ith of a simple iilidin^ or 
displaoemem withonl nmrkti] iingtdur or rotatory motion. It \% common lo nearly 
ail dianiiivMlial joints, and in lh<- only movement Inrtween tlit- plane surfaeea of 
arthriHlial JoinH. 

Morphologically, many liganienlH are foninHl by the nii'tnmor|>hrMii< or rcgres- 
flion of ninselefl, due to loss of function, or by ilie ini);raiton of nin.»cte», or by the 
degeneration of osseous and cartilaginous tinsiie. Thi.-' is shown by a eonJiwraiive 
Ntudy of vcrtebiate Iifl;»meiit6, niiiacles, and bones. Atavistic examples art ooea- 
sioimlly met with in the human ^iibjei-t. 

The ligaments are never strained by muscles tending lo pull (he bonee apart, 
for, on the oonlrary, the action of the muscles braces the Immh-s firmly together. 
Many long museles passing over two or mon- joints co-onliiiale their movcmt-nts, 
And no economize power. Sonie long muscles act as ehastie ligaments, often 
dilTuaing the movement produced by the »hurt nnisch-s over more than one join). 
Two or more joints are M>nictimes eomhined, and thetvby inereai^ their stifngth, 
security, and variety of uiotiuuH, us in the wrist and ankle. 



THE ABTIGULATIONS OF THE TRUNK AND HEAD. 

1. The Articulations of the Vertebral Coluran. 

There are two mU of articulation.^ Ijetween the movable vertchrep — those 
between the bodie-' and ihosc between the articular processes. Thew parts .iiv 
connectetl together by ligamenUi ; but intfrmediale tigamvnU, not connecting purl« 
iu contact, help to limit the movements of the t^pinc and to complete Ihc i^pinul 
cannl. 

The Artloolitlona between the Bodies of the Vertebra (Fip?. 2^6, 2-'iO) are 
ttmjthiarthroiliaL Tlie following lifr-imcnts bind ihcni together : 

Tlie iaten-nifbrai tiiaca nri' tonjih. eliistic. bnt conipn-ssibU- platen, which are 

I>hKT<l between and Rrmly unite ihc vcrnlmil bodies from the axis u> the coc^-yx ; 
>ul in the Hueruni and coccyx they iirc o>i,silictl on Ihc suriai^- or Itimnghoul. 
They an* finnly attached lo the opj>o>cd cuHiwcj* of the iHKlies, ihwe snrfacft* 
being eovcrc«i by a Ihin laver of Mirtilag*', except, near titeir margins. Tlieir 
shape and siw arc the saiin- iis those oi' the Mirfaivs of the bixlics they connect. 
They arv thinnest between the second and thin! irrvical (the weakewl spot in the 
cervical eolnmo), and iliickesi and liii^iesl in the lumliar n^ion. In the (^rvic.al 
and lumbar re^ons they are thicker in fnmt than behind, and thus cause the 



218 



THE AltTlCVLAriOXS. 



c«mvexity forHard in the fiHTiier. ami iiicn-iiM- thai in Itic IjiKit, R'nion. TIiom 
ill tlie thitrarir- re^oii arc tlik-kcr IhIhiuI, iC iiiivwiicn-, iiud si) iin-miw il» curve. 
Tluy form in tlic iig^re^iiti' <itn-HjimrH'r uf tin- h'lt^lli of tin* niuviiliic [mrt of 
till- vvrlflinil (■oliiTiiii, wliirli nfiMJiiu-s ;! Miifili' i-imv, citiifavi' ill Irmit, tin." i-urrr 
itj ofii oi/f, if tli»- ilii*i's arc ri'iiiuvcd i>r ilriiii iiji. In .-Iniotnn- llie <li.s^^ rin- iiin<)r 
iiji of Iwo parts. The rxtmifif nr laminar jiorlion foroiH Diort- tliuii Imlf iIm? 



M«T. eoK- 




II LAMENT 



r 



riu. •M'-Tvio liitDtHir vcrlifbRV lu iuiH>n"l xrvUun. (THIiit.) 

mass, and conaist^^ of conrpntrio lavoi-s of Bbrouit tissue with nmrc and more 
cartilage-cells toward the contiv. The fibres pass obliquely between the vei-tchrse 
and in the revcrwd direction in adj^iining layers. Some layers iire found nnly in 
front, ninkiti}; this jiiirl of the diw ihiclier. w) thiit the rrntrirf ut jm/pi/ /t/irtion it 
Ntliated a little heJttiid the Mnti-e. The latter is a yellowish, elastic, ball-like 
masfi, composed of a line fibrous matrix, iniln-ddcd in which ir- a net-work of 
angular, bRinching wlls, mori' n^lnlero^l^ towani ihc centre. It is m n-mnunt 
of the notoi'liord. On section of the disc throiifrh the pnl]iy portiim lh<' l;ilkT 
bulges out aljovc iho ri-vt, i^howiii;; tliiU it is coTiipn'SMil by lln- hiitiiinir jiorlion, 
eo that it fonii«, iw it were, ii hull or piviil ujimi which the \'i'rli-hni! bcjiiii-s nutvo. 

A fiviiovinl nivtly is described by I.iimIiUii in e:icl ntnd pulpy purlion. Tins 

iiilcrvi^rti'linil <lii'cs are Kurmiindif I on all side." by il .-heath of fibrous ligumenih, 
inirotiiplete laterally where ihe iliiii mill nmrc or h-w .Hiatti'i'etl fibre;* ii-ach from one 
bone to the next, and arc fionietiine.s called the (attral or n/tort veiiehraf lignmcnU. 

The anterior fiinwm liffiimnil i?. the stmn^: bund on the front of the ImhIIfs of 
the vertebrie. It extendn fnmi tin- under liiirfaue of the occipital bone, in the nie<liun 
line in fn»iit of lh<' foramen magnum, to the front of the .-aeriim, reap|>earing 
below an the tinicrior ttarro-i-nrci/i/itil /it/nnirnl. Above it is narrow and cord-like, 
and formal ihe thickened central portion of the atdenor oeripilo-ifl/ttnial and of the 
anierioy alltinlo-ttxial /ifjiiiiirntn. lielow this it beci)nies broader as it di^ceuds. Oi' 
itfi fibres, which are deiiKe, well-marked, and longitudinal, the superficial pasti uver 
sevend, the deep only Wtwecn adjawnt verlchrw. The fibres are atlnehed to the 
intervcrlebnd disev and to the edge-^ of the vertebral bodies, and britlge over the 
nietlian dcpn-«siwnis of their vciitnil ['urfacc, ihns rendering this wirliiee more 
even. It liniilj' exieiwion. 

The pnnlfii'ir itniaiuin ll;/<imiiil exti-iid* iilnnsr tiie dor.<il siirfiiee of the IwMlies 
fif the vert4-bm- within the sjiiiial eiin:d frmii the liusilur groove of the occipital 
bone tn the eoe<'yx. Ilw upfx-r end, often iiilaruinar, fiirniii the iM^fmoi' ocn;>i(o- 
axiiU liyamtnl k'tween the axis and oecipitwl bime. Il iw bi-oaa and even in tlie 
neek, extending eoninletely across the vertebral IhhIh--, nan-ower and dentated 
h«4ow. The broad dentations are at its allachment to the discs and mat-gins of 
the verlcbne, and between them are (he narrowed iMirtions, separated from the 
backs of the bodieji by venous ]ilcxumv. The su[ierficial fibres extend o%xr several 



I 



THE ARTICaLATlOXS OF THE VEtiTEBRAL COI.VMX. 219 



Ten^'lirw. ilip <Iw]> hctww^n adjacent on«8. Its i^nitMith, t^liiiiiitf:, florsal surface in 

ftoiianiti-'l frorii iIr- dura bv loose conncctivo tit-suv except Bl llw fiimmen niagiilim, 
i where ihf- <liini i~ iidliirciit to it. ll limits flexion. 
^^^ The JolBU btttwesD the Artlcnlar Proc«nM ure anlirodial or gli()ii>g)ointe. 
^^Hliry are pruvkhnl with .'tynoviiil <-nviti<-», oiK-Uisod bv on|>»ular li^nmetits, whi^h 
^^■it- lotwcsii ill tbi- iuvk,nIiv>ii^-!-t nnd ii};;hlcr in the lumbar n'gioii.uiid liglitc^^t in 

llic tlit)ra<;ic roKiiin, In ihi* npck thf inner |iart of thr- rajK-uic is f<>rnif<l bv the 

ela-xti* ti-^siK- of till- lipiiiiiniii ^nbflava, which form more and more of the capAule 
^^lii lilt- thoracic and lumbar rcsfion-i, 

^B InMnnedlate Liganmta nnitisK the Neiirml Arches. — The fir/iimentn mibflnrtt, 
P^orapor^^l iif yellow fibrous tissue, connect the lamitiic of udJatM-iit vertebra from 

the AXi* to the sacrum. lu the iijtpiT two Kpuces they iirr- conttntivd, with lcs«, 

or no, elai^ic tissue, under x|H-cr9il iinriKW. .Siipcrinrly they ure iittiiched to tho 

ventral siirfiice of the Inniinir, above Iheir lower bunli-rs, and tiifcriorly lo 

ihc upper bitrrlcrc &\v\ ihe iiiljin'cnt |iiirt.» of the <)ul'^al ^'iirfiici'". They become 

thicker aixl ("trvntjer Ik'Iowt, and are Imwi sixju from in fmnl. Laterally Ihey 

an- <-ontiniiouK with, and form |>:irt ol", the 

Ripf'iilar li^mentit, renohinp iw far as the 

inlt'rverU'bnil fiiramina; mi>ially the lateral 

luilvi^ untie bciK-ittli the n«iU of the siiines, 

I'rotn which [Hiiiil tin- inttyxf,ii,o»>i lUiaiiunt.i ex- 

IcihI Ikii'V an niemhranoii^ hands belvrin-n the 

a^ijai-ent Ixirdcr^ of the Hpines. These nre 

liefl marked in the liiinbar rcfrioii, where the 

libr« extend from the root of one «|)inc to the 

tip of tlic uiR- next aiiove. Iti llie cerviea] 

n.'ffiot) they are n^placcd bv the iiiter^(>iiiale« 

mii*<^lcn. Thev cxli'iiil diirfiillv to (lie itiijini- 

tpiiiouf li^uHrnln, which form a euntiniiniis 

MirJ alonfr the lijH of ihe spiiic?^ from the 

uniiip of flu- seventh I'l-rvicai vi^rtebm to 

ine roccyx, poveriug the lower en<l of the 

Micral eantil. They consist of Innjfiliidiiial 

fibres, of which the deep fihren ctmnect thn 

tips of adjacent spines, and the »n|M!rficial 

pa»i over sevenii. Ahove they are continiiet) 

to the external oceinUal proinberance as the 

iitjitmmtHm nurfue. (Fig. 2J6), fn>m which a 

thin meilian •H^plnm ptijwiw f<)rwanl to Ix' at- 

tiiebed to the txx^ipilal crest, and the cervical 

,pine>. In the lower aniim.U ihc n:,iK- lip.- t^^VSi^^^^V'^^^TT '""""■ *~" 

OM-nt U stmuj^ and elastic, and T>iip|Hir(.'< the « 

head; in man it in of mixi^l white ilikI ydlow libriiti« tissue in !>trueture, aiKl 

forros a metlian intermuscular septum of no fjri'ul importance. 

The itUetii'ansvrrse ligamenU are imiinjiortant niid iiitliiftiitet baiidi* lietween 

the transverse proc(>ssea. In the ibonicic rcpion they are nnimled nnd Htnall; 

in the luralmr region they enrri'S|HJnd tii the vcnlr:d [Kirl of llie superior costo- 

trauKver^ie lif^nient.<< ; and in the cervicMl ri'giuii nre wanting or replace*! by the 

intcrtransverNiiIes muscles. 

The Mfrvf'tuppfi/ is derived fr<im the spinal nerves of the several n'gions. 
MotiemenU. — The spinal column must combine nlren^h with mobility, for, as 

the axis nf the skeleton, it hiis to bear great weight and resist shocks. Kor this 

rmmm, niHl U* avoid titjnry to the eontuiued spinal cord, it in necessary* tluii the 

movement between any two vertebrte should he (^li^ht, while that of the lolnmn, 

as II whole, is very »iti>i<h-nible. Mntiun iwenrf in <ill ilirrvflnnK amnnd the pulpy 

iKirtion of tin- di.M^t il< n ii-ntre, and Vt limited in part by the ligaments, in part 

by the articular ptucess<--s, which tluis M<-:idy the column. Motion ib mot^t free 
here the bodies are smallest or Ihe intcrvcrtebnd diivw thickest. The Ibrmer 







220 



THE ARTICULATIONS. 



condition is found in tlio cervical, the latter in tlit? Itinilmr rcguni, and titesi! »re 
th« twii most movable parts. The dii-et^tioii ol" itintion in any ivgion is rc-gulaled 
by the »l)n]K' of the articular pivM?es-'*if.. 

In Oil- mck till movement are ]K'miitled by the ohliquitr of the articular 
procp*»cj*. Krff-iufifin io more free than elsewhere, and Jltxion is free, but less so 
than in the liiinbiir n^gion. iMterat fiexhn is more extensive than in any other 
region, but il i.-* n (-nnihination with rotation, neither motion occurring freely 
by itself, except in the lower cervicid region, where rotation ie free. Btit little 
motion h allowed between the axis and the third cervical vertebra, owing to the 
thinness of the diso and ihc ovcrlnppine of the axis in front. 

7)1 the Ihoritfif rvijiuii ro'tfnmou is clitckcil by the overlapping of the laminte and 
Spines, as well a* by the siiiipcof the artimliir procewsi*. The Inllcr also pri'vent 
jkrion. As ihi- nrtieulnr prwojw* lie in the an.' of a circle of which Ihe irnire is 
10 front between the bodii-K, rottition in |>(trnnlt<:d and is niiii>t frti.' in the ii|){>er jxirt. 
Laia-al fiexion, otherwise possible, is prevcntwl or gn-ally liiiiileii by tlic ribs. 

hi ike fuvifir/irft/i'ifi, owing to the tliickne.-w of the discs (especially l)el»ecn 
the lower three \-ertebne), Jtrxhu is very free, ej-lnininn ini>dcnitely .so. The 
centre of the circle in which the articular processes lie is situated posteriorly ; but, 
owing lo the fact thai these processes do not fit eliwly logcibcr, a -light amount 
of rotatiim and some fafauf JJexhn are jiermitled, the lateral motion Iteing also 
limited by the great transverse diameter of the bodieji. 

Motion is therefore most fi'ee In ivgions whose curve is convex forwaixi, 
whose spinal canal and the contained -pinal cord are largest, and where there 
are no bony cavities ciMitainhig viscera. The ligamenia subflava complete the 
spinal cjinal, prevent the capsular ligaments from iRinp nipjMHl between the 
articular snrfaccjs during motion, and rcstoR> these suriaces to their normal 
poxitiun arter niovemfiit. They have but Unlc. if any, cUVel in limiting flexion 
or restoring the column to the erect position after flexion. 



2. The Articulations and Ligaments between the Atlas. Axis, and Occipital 

Bone. 

The essential ditference bctwix-n these and the intervertebral articulatiuni- in 
general lies in the absence or nioiiilicinion of the intervcrlcbml discs. The "•{H.-t^iaU 
i»ilion of motion l>ciwci-n tlicf-c lUn-v Ikuics n'sulls in wmie tlitleivnees in the liga- 
ments, though mofit of them aie the eoiitimiaiinn nf the si-nes found below, 

A. Tlie Articulations between the Aria and the AtUs (I'igs. 248, '2'l{lj. — Thv>« 
are here two sets of mrnorinl joh'lx or arlicuhitions : 

1, The joints between the su|K-ri()r articuhir process»-s of the Rxis and the 
lateral masses of tlic utla* are niUinitlin/. Each is surrountled by a mpmiJtir 
lif/rimait, strengthened on ihe inner ami dorsal asiK-ct by an aiTi'inKiry lif/ituutU, 
which pa-'ses frimi the biieU »i' thi' IkhIv of the axi> upward and outward, along 
the outer edge of ihe oci-ipitosixial ligament, (o tlie lateral masii of the atlas 
behind tlie tninsversi' ligament, 

2. Tin- articulation^ of the cKlontoi<l process in the ring between the ventral 
nmh of the alias in front ami tlie transverse ligament behind are of the IrochoUlct 
oiaaa. I'here are two nifnovial tave — one in froiit, bctWL'en the odontoid process 
and the atlas ; the other and more extensive one hchilid. Ijctwccn the otiontoid 
process and the transverse ligimient. These two saes are separated by traiii'versc 
fibres, which pass from the sides of the mlontoid prot-csc to the atlas, in front of 
tlie tnlwrcles for the tr.insveri.e lignmcnl. The frtin'rtri'c liijiimnil \f a thick, 
dense, and very strong bund, which [Kisses acmw the ring of the athix between 
tlic tnlK'R-les on ibe inner side of its latend ma.'^ie.i. It \* an-lk-d slightly 
backwnrd, ItattcncHl fivmi before iKiekward, and eurtilage-idad in frtint as il jtaAses 
behind the narrowed and faceted neck of the mhmtoid, which il holds in place, 
and by no diilng prevents the odontoid fnmi pithing the ^pinnt eonl. t'oninirv to 
tlie uommou jHi|)alar and professional l>e)ief this ligaiuent seldom gises way in 



THE ARTICULATIONS BETWEEN THE ATLAS, AXIS, ETC. 221 



huDj^Dg. Prom uixl ucmst; tli<> ci^nin; nf it)f dorsal aspci-t thin t>iin<)loH of fibres 
piisw iiptvan) iiihI liiiwnwani tn (Ik- rnittini Kspcct of thr iintcriwr bonier of tin- foni- 
, mi'ii Tiiii^iiini iimi lo IIk- iloixnti of thf limly of ihv okh r(*]H'ohvfly. TIm-** 
with (in? iran^vrrwc |>c>rtioii fonn n rmw, Iii-ih-v \\\v iwinK- iTuria/ (iifitmml, noriio- 
timt^ a{i{>tiHl to tlw grmif). Two oIIkt li}!:iiiifot'< iiiiilv- lln' nxis iinil fttlCM. The 
rior atiatUo-ax'utUUfiuifHl it n liiiii nicnil>niiiv bctuci-ii the vviilml nrcli of the 



U*II>H noct** 



■NTCmOa LIOIMCHT 
■ HTtHlOH l>GCll>lTO- 

LIOIHCHT 

aTLki 



vfincaiu 




MICSK OCCiritO'lIIAL 
LieiHtHT 

TumatfcKAC 

UOAWtHT 



*0»TIIIIM 



Pm. 2«l'-(taf itlal MCtlnii uf Ili#]ulliM IphIvcvii tli« <m'ItI|>Im1 Imiic and Uie Mliu anil sxIil (I^HtUI.) 

AttiiH and iho from of tlic IiikIv of tin: iixi>, n']>nT:4<-iiliii^ ihi- nnierior oonimnn 
li^ment, wIukip direct upwiinl continiiiitiiiii ts i^vn it» ii nu-dinii conl-liko ihk'kfii)- 
in^ of thin ligament, wliioti Im aiiai-li<il to the vcniral tiitiercle of the atla.-v The 
jiosln-ior atlaftlo-axliil lii/ittnrn/ n'i)n '■"<-»(.■• lUf li^iiini-iila wiiltBava, but ha.- lilllc 
elastic tissue. Ti loosely oohiiwIh iht* dorsal areb of ilie atlas and the lamiiiie of 
tht- axis, and i^ piTf'iratrd on t-.iiAi ^'u\<: bv ilic ■iironil ci'i'vical nprves. 

B. Li(tus«nta between the Axis and the Occipital Bone (Figs. 248, 240). — 
The occipito-ftrMl or oeripitu-ftrfiml (u/amfnt ia tlie uppi'r end of the posterior 
common ligament extending fnmi the third and wvond wrvieal vertebne to 
the basilar groove of the oeeipilal bone. Some of iXm fibres pa>* over the axis 
without attachment, giviiit; rise to two Invent, of which the hind one may W 
<icsiRnated the po^m'or, and the forwanl one the mliMfr, uctrlpito^txutl fii/iiiaenl. 
The tfitri-at wlnntoUi, iifnr, or ehfvk (ii/aini-iif" are two ^troiiff fibrous eonU, which 
extend from the sides of the summit of the odontotil j>p>cec« tmnsven^-ly oiit- 
wiird to the nnigh tmprett»ion on Ihe intu r wide of ciieii iwcipital <Mmdyli-. Tiiey 
lio at 11 little higher level tlwn the I riinsvcrsi' lt)rtini<-nl. Kneh i" made teniK* by 
turning the IicimI to the opiMwile Mile. The miiUHr lulimloiii or xiiK/miwrff Ht/ti- 
mi-nt (.interior o<r)-ipito-»xi:d li»iimenll i* a nlender, median, librouH Itand oonntMrt- 
in>r the ap-x of the odontoi<t ioid the fore part of the margin of tlie foramen 
raui;niiiti. it in ri'tnxcd by flexion, tightened by extension. 




223 



THE AliTfCVLATIOXS. 



The i)iiH])ciii*(>rv lifrinK'nt U \\vr\vM fri>ni tlit- ^li<-iilli of (lit- riiHncliorJ. b<rtu'«cai 
the first vertebral coittniiii (tlici:)(Iotituiit)Hi><l ll"' liii8i-<i<:ci]iitiil,aiid i>^hunit>l(>guu4] 
with an intervertelnal liiw. Tin- 1 musviMsi- mid rlui'k liptiiii'iiis un- i-jch ilcrivc-d ( 
from [ht"v»t/M7i(/////'ry;irii/A[Iijpitiii-ntiiiii oinjiifpilri'iB'liirniri). TIii'm-, in thi" I'nilirvo, ' 
connect thi' liontls of i^di j>!iir nf rihs or costjil |n-cici---i«i-s iiroiind llii> tKicl; of thi.' 
intervcrithral iltnca, ami |>ersisl as the iiitfranii-iilar lignnivnt." uf tin- IiwhU of iIk" 
ribs. 




Fic-, ^«i.— ArninilBtiiiiu or iIil- iwdpiul lionc wlih Ihc uppct ccrrlonl ivrwbne. Tbv anht* luivc bnn 

MovanenlK. — In the nllanto-eixial artii-ulation n>tation cf the ht-ad tojtetherwjth 
the atlas takes placv arotind the <x!oiiloid |»r<H?e(^ iw a pivot \'<>v about 30" to citlipr 
Hide in a nearly horizontal plane. It i-^ liinitc<l bv thv rlu'ck und Htlanio-axoidfati 
li^iincntf. Aii both faeetfe in eat'b 1at<T.iI iitluiKiMixoideuii articnlaiiou iir*- «iju- 
ves, with the convexities in eontact wlien the bead I(M>ks forward, iiilation eaiis^-s 
the eonvexitit'S of the allantnl facets ti) descend fnim ihiw of ihi- nxi:-. ThLi 
deorc)i.'<-* the K|iaee and rt'lnxes ibc Iiinini<-iil:< betwii-n (he boiic.-, tliu.- allowing 
fnriiit-r mtalioTi, with ^eeiirity in all ]M»ilion;s. Sli>;]it tli-xion tiiid exten.Moii a:iil 
Mtnit- littenil tli-xioii an- alsfi allowed betwi'en ihc allii^ uiid the iixU. 

<.'. The AittcTiUtlon of the Atlas wltli the Occipital Bone. — Tiling eonsistH nf 
a cynnni'trieal pair of i'on<lvljir joint-* between ilie oe<?ipiial condyleB and the 
iipiier iheil.- of the laleriil iiiaN-e-" lA' the alliiv Kiic-b joint is pirividtnl willi n 
fiiituT lax i-afixuliii- fli/ttimut. In front and behind ibe-«e the ventral and dorsal 
an*hes «f the atlas aiv connected with tiie tnai^ins of the fominen magnum by 
the iinierior and iiovtciior wcifiiio^ttfniitiit /ii/'niiaitf fft-pi-tivelv. The aiilfrioi- 
fM-iiilto-aiUintal hifamrnl is thin and nicQibmiious, e<(re»^l)ieiied in front ill the 
meitian line by a round iit-efnsury Hgmnfnl, which is the iipjior end of the anterior 
eomnion lijpiment. 'YXw finrin'iw orriiiifn-ittlnulti/ li</ummf rejiivsentv the lijia- 
mentuin nnbflavum, but in without elastic libreA,and is also ihin uud nienibrauoiu. 



k 



THE AltTZVrLATIOXS OF THE THORAX. 



223 



I 



hiti litniticnt dues not limit niution bctwopn tlip IwtM!^. Thv dura is adlxTknt 
to \\f> vi.-nlnil "tirliuT, aiul tlic dnrxil i<iir£ira- Iick in (he tlnor nf thv i^ulMKc-ipital 
iHiinglc. A liiiiwl i>r lilm-.s al tint jiilonil miir^iti- "(' tlic liptmciit arelits over the 
Iwit-k "f tin- vrMchni! n'"""^'*' "" '"J"''' "'''<" '" ''"' *«i|>"Tiiir nrticiiliir prorf**, vom- 
pk-tiii^ 11 loniiiioii for tlio viTli-bni! iirl<-rv iiml ihi; Mibcici-ipiliil iutvc. Tlic /iifrrai 
occifiiUr-ttllnntiit ligttiitriita arr; Alroii^ librtiiH IuiikI.'' I»i*twii'ii llic lni«sv«T««.' pntcvwca 
nf \\w- alius and tlii? jo^iliir prt)Cf.-t!W7i nf llto occipiliil on cju^li Kidv, which 
Hln'u^tlN-ii ilii> cap!4ii]ar ligainetilfl externally, uml lit- WiimI ilur reiitiut aipitix 
l;iti-niU.t niiiMtlcs. 

J/vmnm/j' of //cj-tV>(i and (irfntMow nri' frwly ullowi'd. Kxlcnsion is olnvked 
by ihf' juii'Tior <«vipiti>-:itlautal, flexion Ity thi- m-a-i pi to-axial iiml hind |iiirt ot" tin- 
taptinJar ligjinionls. Some hleml t/fiilinff in al.-ii allowed, l>y wliieh the outer 
edge of tlie oondylc on thv one side is dcpresfled, and on the other in eJt-vated in 
re)iili(»n to its sockc't. Or tJio movi-ment may l>e Miijufig fateral, one rondyle 
advat>cin^ $Iij;htly at t\w stuoc time tliiit it is tlejire^iscd towan) the medial) tin?, 
whili- the opiK)*ile wMidyle tukcK tho rtverw? |ii>si(ion. This is the |H<sitiun of 
gmiti.-«t stability, and i-^ a^^nined in iIk- II1IK^I easy and natural altitudes. O'ln^il 
morrmattn are n.-»lntined I>y tli<- ehei-k ligament!^ and the liiteral part? of (he uii>- 
tuU'*. \" true rrifiitiim U allnwod. 

Tho ■vmmi'lrical an<t hihit^Tal nrniri^-nteiil of fli('!>i' juinl.^, oonihiiied wiih ihf 
niiiliun (Khm(oid pivot, provider* eipi.-il f ciHhjni urniiitinn and ^rentitr sln^n^ih and 
Mi-iirily than a hall-arid-siM-kcT joini. A [Ki.-*<ifri'wav for (In- eoni i-i al^<t provided, 
■iihjit'l (o U-^-i nioiioii (hiiu in <^ne ihe jnint wvrf of the hall-and-jioeket vari<*ty. 

The lipimi'nl* [Kix^inff over an<I iM-lwecii tin- niliiritoid prm'c_<s and llie iK'<-iptil 
by Ix-iiip \:i\ ill ihi- en-el piHiliim iilhiw of IU-\i"ri, wliieh lif-htoii,'* (hem. Ttio 
in-iid liiilancit-> n|>oti the fore jKirl of th(> I'ondylc^ whiti llie orhitn look a little 
upwanl. Itv this armngt-mi'iit, oharaeti-riKlti- oi' ilie limnan fiifiire, the head is 
held erei-t u ithont niidue muncular cffiirt or a ^Ir>i[i<r li^::ntieniiini niiehie. If the 
luiiH-io relax, thi- head will nod ■ilhii' forward or haekwurd acconling as the 
ci-nln." of [iruvity is in front or l^ehiiid the Imlaiici! liiiv. 




3. The ArticQiationa of the Thorax (Kip*. 250, 2->1). 

A. The Costovertebral Articulations, or iho-^e lietween the rilns and tlie ver- 
tebrw, are subdivided int'> ro'f'i-ernfrti/ and cMfo-lrannm-iir iirtirii/fitionf. 

(n) In the nwln-jvittrfit utiirnfutiiiii the head of tlie rib i-^ united to the Iwdy 
of a cingle verlebni in the ca*** of the first, tenth, eleventh, and Iwelflh ribs, 

where to ihf liiKiie,* of two vertebra- and the interveniii^r i liter verlebral 

iw. When (he ril>-hi'ail nrit('nhite.-> with a single vertebra, llun- if a itin^U; 

iai mr. olIiorwLw two sejuinitc sic*, vurroundt-d by a nijii"tltrr lujataml, 

ich i> o<>ni|io««l of .-ihort. librc und iw ri'iiiforeeil in front by the anlrrinr 

khtfidiiil or tiMI'ili tiffinuriit. Thi" eoiLsi.-.(.-< of |K^irlv- white tibn^, radiating 
from the front of (lie head of (hi- ril) iiiiwani to l\\i- ixniy of the veriebr.i al»ovc, 
forwanl to thi- inlerwHebi-al <iiM', and uowtiwaivJ lo the body nf ii-* projKT ver- 
tebra. In th«' ease of the first, tenth, eleventh, and twelfth ribs the stellate 
arrail^ment of (ibres is not quite w^ distilict. The inttrrardculur ligametU is a 
thin, ininsveree hand of shorl. strong fibnis belween tlie Intervertebral disc and 
tlie ri<lgu svpanitin^ the two faeels on the liend of the nb, excepting the first, 
tenth, eleventh, and twelftli, wlni-e it is wanliiit;. It separates iho two synovial 
es. ami is liKjse eno(i<;h lo allovr of moitenile rotation. 

I(« ti<TW-*»J/)ju/y iis dfHvi'd from the anterior tmineJies of the thoracic nerves- 

(b) Thu fwrfw-Zri/futrfrmf tirtU-u/itli"n i^ bi-Uvtin llie tiiberele of eaeh nb of the 

|>|K'r ten |«air!> and the front of llie lip of the irjitwvenw proee** of the vertebra 

bearing lli« .same numlKr m^ the rib. Kaeli joinr lia« ii ihin, hnwc <rajmilar /m/m- 

neni, enelowinn a Kifiiuriat wic, and .-iiviifrlln-ned on (hivi; nidcs by the eiislo- 

transversc liifanu-nts. The miiUlle i-u«l<i-lnni*rfi-xr or iulrriMntfouK ttij<iiiu-nl coiiHiM." 

.nliort hariKontid fibres between the biiek of the neirk uf the rib und the front 



224 



THE A RTICULA TIOXS. 



ui ihc 4<orn^{mii(liii^ tntti.%v«T>iT iinn^eHS, extciKling tVoni the uiji^iule of the 
cosUi-cenlml tn tlint of \\w Mjwtti-tmnsvcrjto iirtiitiiliition. It i" lw!*t won in s 
tranxviTHi' sifliiiii, jiiiil is riHlinifiKary in iJii' ruse (if the clcvciitli hihI (woinh 
riii!«. 'I'Ih- jHiKl'-niir i-iuttii-lrfitim-irif /i;/(itnriU i.x a nliori ntnmtr Imml i-xii-iiilin^ 
friiiit lln- tmiir i'IkI of rlic tniii- verse process oiitwanl and iipwari! to llic mnjili 
tKiii-ai'ik'iilar |>arl i»f tin- luhcn-le of the (-orn'Hjifimiing rili. It is uaiiiiiit; to tin- 
eleventh and twelfth rilis. The mipn'ior cwdtr-trnntcn'Hf fifffitiu-iit con^^irttR of n 
broad, flat, fihrons band iHlweeii the upper Iwnler of the neck nf each rib below 
thf first, and the lower bonier of the tninsverse proecf*« next above ii. Twti layem 
are often distiii^'uir-hnhlc — the ventral, piDi^in^ iipwiinl and ontwarc!, tlio dorsal 
and more i-«itlen.d flhrc,'^ jm-siiig upward and inward. Ivxieniiilly thi-; lij^^imenl 
is continuous with the iiiseia iinin^ the cxtcnial intercostal*' : intornalh* it pret^ents a 
free margiu and is thickcocil ; in front it 'n^ in relation with the intorcwtal vcsst-is 
nnd nvrvoe. 



TRDHSVCIKE pnoccss 






UNTDHOK COHI- 



llltr«<I«K COCTO- 




VIHSt UOAMCHT 



>0«Tf aioo «0*T«- 



Fid. mi.— AHiriiUtinn or lliv vimvlml iKHlIm wlih 
«ich other, *ni) vt tliv nU wltb lliu (]iiiie. <TcilUl.) 



Kiif- IKI^-^'imtti-YvrUtinil unti-tilKllixw In horlmn- 
Ml tn^loii -. iiinwr mrfuic "f tovirr tegtavni, ili^l 
■Idp. (Tfflut.) 



B. The CoBto-chondral Synarthroses. — The costal canilagcs are join«l to the 
ciip-sha)K?<l ends of the ribs by tin- cimliiiiiity of the invet^tin^ perichoi]drium and 
pcriftstcum. 

C". The Chondro-stomal Articulations arc Iwtwccii the facets on the lateral 
border* of tin' sicmnni and tin' inner ends of the carlilaKi'f of the iip|x'r wven 
(the .-"tcrmd) ribs. The jii-xt rib is joined by ij/ncirWiivwji to the sternum. The 
Others have KifimnVi/ jWnN. tt-iierally ninj;!"", bnt in tlie aisc of the weeoud rib 
ii.siially double on one or htnU Hides. When the .tynovini siie is doidtle, an inUr- 
ailii-ufiir ligamf.nt oonnect.* the ridije botwi^n tin- faeetii of the cartilfi(:c with th« 
fibiijciirlilage between the niaiuibriLnii and IhhIv of t!ie slerniini. A sinnlitr tigament 
.mitnetinu-.i exi.^t-* in the other i'unt,><. The synovial mie is frw]i:ently oblitenited 
in the joints of the .nixth ait<l ,-eveijtli ejtrtilafres. The chondro-stenml joints are 
siirrounde<l by ^hort i-ajiMJilar llffamcntx, mom deveIo|>ed in front, above, and bidow, 
where they are called, respectively, nuterior, mipt-rior, and iiifti-inr ilitnufrefiirrnal 
liffOmenU. In the interior Hgament the fibres radiate from the front of the inner 
end of thceurtilujre to the front of the stermini, where ihey deitissate with theoppo- 
»te li);anient ^nd adjoin those aliove and below. The so-called paiiteyior chonifro- 
lirrwil liifiimnif h little more than the <-oiitiniiity of |)eriosleuiii and j>erichondrium 



L 



STF.RXAL AliTICULATIOyS. 



225 



■ [Mnial cvnoviai inviiv wiiri it i:ivi-r oi ciirniBp" miovc ami bt-iow. llif 
of \iw rniiiuliiifc oliontiro-.stiTiiiil lijrami'itlH iiri<l thi' iH-riimtciim, n-iiifwn 
l<»n(ritii<liiii(l fibrcjt in ffntit iiml lichiiul, but e^pt'cially )ii')iiii<l, Ktivii)r|lic 



Witli a frw Rrtvssiiri' cn}iL'>ulnr fibnrs. 'I'ln- rJinHilrn-ri/thniil fifftimfntf if n fiat bnnd 
connect iiif; till- fnml of rlic xiplmiil (-artilngo ^viih lliiit of Die seventh, nrid oOcn 
of the sixlli. <'iHi:il (Mniliij:i-. 

D. Th^ Int«rchondral Artieulations are arihrodial Joinbt tx^ln-fwn tlie cnrlilngcM 
from th« »>i3ctb (o the ninth (incliu^ivo), Htuale^l a little in front of their (i|m-iifxl 
bi-nd, where blunt processes on tho lower edges come in cwntact with the upper 
mur^ia^ of tlie cartilu^-s helow. I'hcy Imvc a complete eapmUe enclntiing a 
fytioriit/ iHtf, (ind rrliifof'd Ity ohltijiie llbrt* frr»m the anterior intercosfal fa^^/'ia. 

K,. Sternal Articulations. — T)if iiiiioii of the manubrium und IxkIv uf the 
iitcniura forms a syiupiiysis in which the iiiiiuix-tiiii; fibro-CMrtihiRc miiv eontiiin 
■ [Mrtial synovial inviiv with u I:iyi-r of ciirrilBp- above an<l below. The Gbrt's 

n- in forced by 

ICIl till- 

umon of ihi->f* two jKirl.t. The xiphoid carlilaire i- siniilitrly iiniieil syniir- 
thr'>diallv to ihc lower end of the hotly of ihe Brcnnim, at a Icvi-l .loincwluil bi'biiid 
that of the ventral >nrlJn'o of the sternum. The <liontlro-xiph<iid liniment is an 
act*nw>ry ligament of tiii;; joint. Hfith of the connecting eartilogeii, but eftpeCTaliy 
the ftterno-xiphoid, may o-nifv in old age. 

Jforcmmb »/ (hr tUfig ami oj Uk Thomx as a Whole (Fig. 252). — In inspira- 
tion the thorax is enlarged in its three* diameters, Uansvenie, anlero-po^tcrior, and 
vertical. The increase in the verti<ail 
diameter is ratised iwrlly by the eleva- 
tion of the upper ribs, umt the reisult- 
iiifT widening uf the inti-niwt:il s[uicr.<, 
but in mainly due to tin- actioti of |]ii> 
diaphragm. The tncrcar^i' in the other 
[WO dint'tion.-i i^ tine to (lie move- 
ment.'^ of che rilin, whieli aiv grwile'it 
where (he riliw arc loiigt'^t, m<wt ob- 
li(]Ue, and most enrveil nl lltt'ii' angles 
(i. e., at the ^ixlh, flcvenlh, and eighth 
ribs opposite the bulkiest jiart of the 
laiupi), and least in the ahori, tlat liret 
ana second ribs. 

As the ribe articulate with the 
veriebrw by two series of closely ap- 
proximated joints, the axis of rtAfition, 
which i» the chief movement here, 
miii<t |>ii^ through )>uth joint«^(. c, 
ubliqui-ly outwanl. backwanl, and 
Mimewli.-it dtiwnwnrd. When the i/d- 
uvinl r'lliiliiiM <;?' owyMivrfwH occur*, tile 
ventral endn nf the rib:', which arc 
inclined obliquely (hiwiiwai-d, an- eleviited. By thn^ docrcaising (he obliquity of 
the rib^ the front wall of the thorax iji carried upwanl and forward, and il!» cavity 
is enlaiTged aagittally. The vi-ntral ends of the ribst lannnt W elevatwl without 
Htraightening out the angles with the co.'ital cartilages, which throws thi.t em! of the 
ribs, outward, increasing the transver-ic diameter aiiieriorly. The return of the (•«»• 
tal eartilageti to tho natural angle utter inspiration in a principal factor in the 
resiliency of the thorax, to which quiet expiration \^ lai^ely due. As the nxin iif 
Totalu/n in oftliqur, upward rotation also elevates the Uiteial part ol' the rib,-- and 
everts their hiwer bordcrv, thus increasing the tramsverfie diameter )>ehind. In the 
first rilw the axin ii< mon- ni-arly tran-ivcrw ; lienee their motion is uublly a slieht 
elcviitiou and ih-prcwion of their fore parts. Itiit as the obliquity of the axis in- 
en-jisirn fn>m alHive downward, the ou!M'ar<i movement becomes more extensive in 
the lower ribs. Owing to the plane mid sloping articular snHaccson the tmns- 
VQnm prooes6&4 of tlie vertebra-, Irom the wventh to the tenth only, (here i*, bittides 




Fla V<t.-inm 



lunm of the dUTilucmcni of Uio rits 
■nd lUrniun In in*Trlmliiii - 'i IndlCAUt Ibo ilivnv at 
upWAnl muvuiatfnl; b^lhitl uf f4>rmu<d niuvifinviil. (Xt^ 
Inl.) 




226 



THE ARTICULATIOSS. 



robitioii, II ^lii^lit lini'kwnrd iiiiil upward motion at the cot>tfl-trftnftV(>rAC joint in 
iuspinttion mid tln' ci|i|i<>;>it[; in cxpirutimi, which \t- »lill mon? marlica in iho 
fli-vftith Hill) iwcll'lli rii)K, wliiTc tlitri' are iio cj^-Ki-trjiK^vcree articuliitioiiH. In 
llic ii])|KT six rilw, whprit tin' fiiwls on \\w. Iransver-t- [irijcciwps arc mtuatetl Iohxt 
iind iire iiiuro wmoavf n;* Wf iwccinl, llifrc is rotation only. In the cai^ oflhe 
cli-Vfiilh ami twelltli rih» tliert? i* liiilt- i-lcvatiim, ami tlif iHclt'lIi ril> may t>veii he 
drawn dnwnn'ar<l in iui-pi ration by tin- ({niniriittiis Inmbonmi. Thi- wiil<'iilii|; of the 
lower |Kirt ot' the thorax in iiiK|>iiiili'>ii iiii'iiiisi'* tin- |iiivri'r (>f the diii|ilini['tii and 
(•niinteraetsthc i-ompn'ssioii of tliialtdiuiiiniil viwrra. Tin- instn-verlrhnil iirtit-nia- 
tioiifl with Ihpir (?i?a?#li-«.t miiVtiiH-nt an* rtiicnkalih- for fiiHr IrcHloni fmiii (iisiasi-. 

At the chondro-stern.il arliciilatioiis, oxcfjil flu- fust. iIiitc is ;i i-lifilit hinge- 
motion on two aspc, siivitial nnti obliquely vi-rtieal. Owing to lhe*e two move- 
ments the stcrnnm ih carried neither so far fot-ward nor upward a« lln- anterior 
ends of the nlis and cariilages. Unless thus limited, iis motion wonid he dctri- 
nirntal to the heart and ureal vessels behind it. In the interehondnil joint.'" only 
n liniiUil ciidinj; if* allowc*!, and the sternal articiilaliuna merely inorfa.'*e the 
ela^lieiiy niui Ktreiif^lh of the t-ternnm. 

The hinge-motion, ot\en wRmijly ascribed t« the rilw at the pnM(V<^>nlrai 
joints, c-jin only wciir with a slidin); motion at the Liwio-tninwvcrse arlicn- 
hition. Although tlii» may <><-cnr in the lower ribs << eannoi in the np()er, oiiin^ 
to the nxuided ooncavilio in llie triiiisver»e proei-.-wcs. Siif;ht rotuiion on a single 
axU, VA above indiejitt'il, a('c<ni»ti> for all the motinnti a.scribed to the ribs. 

iA. The Tempore -mandibular Articulation (Fig:^ 25^255). 
This articulation consii-tK of a pair of ^ynimctrie;illy plaeixl r/ififrfpiw-iaihrt) 
dial joints. Their dissimilar artieiihir snrfiiee!^. the ventral halves of the jjlenoid 
tos^ss, and the articular emttienei-s of the s(jiiamoii« portions of the teni|H(nu bone* 




iriciiiaoiBEua 



Pin. SiS,— TvnipoiD' iDMiillhijliit Hrtii'uluilntj In >ui.^iiuil icolloii. |T»IUtO 

above and (he <-onilyl<--i of ilie inandihk' below, an> udjnMcd to one another by thi- 
inli-rposeil inifniriiiLiIareariilaKf.-, T!ie joint is best wt^n when the jaw is divided 
iu from of the ramn-s and the latter is freed from its attaehmenis 



an 



The Ihtnes are united by a thin loos*- atpmt/nr llyament attached ontside of tin- 
icniar siirfaees on the two bones. The fj-li-rtui! Inh-rat tigamcid cinisists of 
tliiwe aoceasory tibn-s, slrenylhening the eapside, which pass from the lower border 
and iiibiM'cle of the KyB<)ma downwiird ami backward to thi* outer side and back of 
the neck of the eondyhr, Thii liganniii <in either side serves as the inli-rnal 
lalernl lipmieni of (lie opposite M<ie. The inner jwirt of the capsule, wmietiniea 
calletl the short inleriiul latenil ligament, doea not deserve the name. 

Th« internrthutar iivtUnyi- is a ihin, oval plate of fibro-cartilap*. conMi\-o- 
convex from tiefore baekwaril on it^ upper aspect to fit the teinjMind surfaoo, luid 
conoave below to reei-ive the condyle of the lower jaw. It is thickest bi-liind, 
Bnd thinnest at the ei-nlre, where it is sometimes |XTforateil. By the close atlach- 
ment of its cireumferenec to the cappiidc the joint is divided into ltr<i irpiorial 
eacUitK, of which the »pi>er is the larRcr and looser, and Ih*- lower «xtend* lower 



4 



TIIR TEMPORO-MAXDIBULAR AUrirULATIOy. 



227 



down l*ehind ihan in front. TIk* two ^lo ciniiiiiiiiiii'^ti- wlicii llic cnrtili^to m 
|K'rfoniU-<L Somf fibrv« of tin- fx(frii;il |>U'ryg«i»l nui.'x^lt- art- iitHt^rUi) into tlw 
cartilage in front. 

Tlie atveaory lltfttmrNU an- — (1) tin- xp/uno-autHtlibutar or lorn/ inbmaf iiitrrol 
tigamet^, a tliin buml name little ditiUitiue from the joint, extending from the 




Fin. 3S4.— Tcmporo-maiidltniliir inlcutiilliin. cxtvnml view. (Ttilut.) 

spine of tl»e sphenoid downwiml and a little forwani to tln' liii^itla of the man- 
lulde. Se|mrating it from llie joint and the nimnH an' tlit external ]>t«rygiiid 
mnHcte, the in1i.Tnal nmxillnry vt-ififrlh', tin- irifi'iior ik'iitiil nt-rve and vi-skvIs, tlie 
aariciilo-tcni|K>iTil nt-rvc, and llic niiildlt' mrnin)j<!il ;irlfry. It rtprcsciits llie 
libroiLt remaiii'i of fl jmrt nt' Mivrki'l'?^ atrtiliiK'r, (:ii 'l'\ii.' vtiflo-ni'imlibiihr tli/u- 
ment is a "pccialixcd liiuxl of itit- dwp rcrvicid fiifcia extending from mur tin- lip 
of tlic ntyloid process to tlic an^lt-.ind tin- jmi*- 
tcrior Imnk-r of llic iiiiiin* of tlit- jiiw, U'twi-cn 
the mmwiter and intt-riiid plorygnid miisolt'jt. 
It w^imrate* tlie Hnlmmxillnry from tlic |iaroiid 
gliind. 

Tlie ueitv« supplying the jolnl an- branohes 
»f the ntaiiseterio and aiirieiiriMem{)oral. 

The morvmeHtii in ihin joint art^— (1) the 
hinge-motioiui of eluetilion and def^reamon, and 
(2) the giiding motion* of pyotrugimi an<i re- 
trtir-ti'm. both (a) simple and (h) obliqne or 
gnndii));. The niovvmcnl:^ in tlie two ii^yiiovial 
c'omjKirimcnIs arc of diffffent kiiidh. In llir 
upper then- arc a prntnision and a r(ir!K'tii)n, 
or a forward and a lMii'k«ariip!kli[i<i,i)t' tlieair- 
tilngc lo|p;th«rivith llu- foiidyk- on the teinjioni! 
bone, due to the eiosiT ronmrtion of the carti- 
lage with the eondyli' ttiiin with lln- t<-ni|Himl 
bone, and tolhein!*i-rtionof tlifcxicniiil pury- 

piid or protnisiir musrli? into liotli mrtilop- an<l eowlyle. In the lower part 
there i« a hiuge-raotion, on a transverw axis, between tlie condyle and th« 
cartilage. 





Flu. SA.-~Tcni|io[<>-muidlbuJ*r ■rtloul*- 
nnu.mmiU vtuw. iTmIuU 



S28 



THE ARTICULATIONS. 



Ill opcniiif; the moiitti tlw fl) hirifti* ami f2n) i<ini))lc pliiiinir iimti'Hi* an- riom- 
binvtl. W'lii/ti till- iiiiiiitl) it "]iMnil }nit iili^litly Uw in lalkinj:) tlniv in midjiIv u 
liin^'-mnlioii in llic luwcr coiii)Hinnti-iit. Wlicn, Imwfvcr, the moiilh is o[)eIM^d 
Riori- nixt more widrlv, )xi>i<li'>! iiii in(-r(-ii?M-(l liiiij^*-iiii>li<>n, tin- »irtit!ig<.- nn<i con- 
dyle ffliili' forHanl imlo rlic iirlituilur fiiiiiiciii^. Tin- onmiylc <Ick'k not iioniiHlly 
nr»i'h tli^ Hiiriiiiiit of lln- i-itiiiii'iKi-, hut u'licii, :lh in n <-iinviil>ivc viiwii, it glides) 
over tlic- siinimSt, it slijis into thf xvgoiimtic futui:!, anil (liere i.« n dinliK'ulimi with 
nijttiirc 111" tlie Ixiok of tlw caiwiile. As llie fartllagc and *oiulyl<- ftlitU- rurwurd 
tli<- i-\ti'rriiil liiti'nil liguni<-iil n-iiiiiiDKnIwnvH tcnwi' on lU'coimt H ) uf t)iv dowiiwiird 
inovi'tiii'iit. mill I (lu'i-iiiiiK-iii'i-, ('J) uf ihi- iti(rrc:iKi.-(l i]iti{;i--m<itti>i] (lU'jircwiiin) w)ii<'h 
llic li^aiiiciil allows when its ol)lit|iiity is hlraiglitt'tK-il l>y \\\v fon\iiiil niuvemrnt 
of tlip coniiylc. Ttie (»i)iiit of IcjiKt iiioliiin, or llic lixi^ of molioti, in the CMva- 
bincd move III (lit \^ ii|)pi'iiximiit<'1y at tin- infi-rior <l<-nlnl fonimi^'ii, and iIiih >itrptch- 
in(; of tlic- iRTVi' in Hvoidcd. Tlii- i.-oiiiliinalion of Ijingt; mid jrlidin^ niution gives 
It tciiriii); lis well lis ii cnltinir gicliiiii to tin- incUon*. 

(2") Tlii'i'f tuny lie :i Khn/iti- fifiltnrion and retraetion of tlie lower juw by it 
jfliditif: iiioti'iii i[i thf upper editijtiirtineiii. A sliplit lowering of tlip rami ott'iirs 
M.-v llie luriiliigof iiikI i>Hi<iylt:.i ^Kl^.- downwartl and forward onto the eminences 
('2fi) An ofillfjiti-/f/ horizonfitl or ralnrii f/riiuHiitf motion is cau-ted by the alternate 
glidiii}^ forwani on one Hide, and Imekwnrd on tlie "tlier. 

THE ARTICULATIONS OF THE UPPER EXTREMITY. 

1. The Sternoclavicular Articalation (Fig. 25G). 

The ai'throdini Joint Iiciwwn the inner end of the elavicle and the superior 
anir'*^ "^ 'he manubrium ^(erni, togi-llier with (In- eartilagc of tlie fir^t rib. is tlw 
only ]M>i!it of aiitielimt'iil of die »keleloii of ilie 4ioiilder-^irdle and iip[KT limb 
to that of ilie mmk. TIn'di«sinntiirarlieiil:irsiirfiiee-s tire adjusted tooiieimothcr 
by tlie inlcrvcniii;; p'/»i)-c(ii-(*V(«/'*, ami an- itmiieetMl top-tln-r by a fairly tight mp- 
witfu- tiifammt, w biM> tibi-e^ paw nlilii|uely upward and imtward from the circtimfcr- 
enw of ilie sternal to that of ilip elavicnlar fiieet. This eapsnle is stroitg<eDt bt-hiwl 
ami in front, where it is ealled reftjH-etively the potienor and the tmtrrwr Mrrno- 
davietiiur (ii/amaxU, Above it is supplemented and strengthened by the denw intT- 




FK, W^— «(«KMya«i>-claiKal»rutl«ul«lloii. ftviaidir*. Tlu rlcfcl Iwtf t» M«u la earonftl noUfo. |TtMDl.l 

elari'-*it'U' HyttmrHt whieh pusses lietyrccii the upper and b4U.-k i«rt» of thv firnutl 
tmU of the two cLivieles uml tlK-ir cAiiKiiUr li>raniet>t», amt di)K down in tlie 
miildle tobcuittirheil tulhc posterior Iwnler of the interv-Iavi«,'«lnrn"lchof tin.- sier- 
mun. Below, wkerv the ca|»^iile i» ihiniwst, is ihv stiuiig, dviise, a e ccasory bond. 



THE SCAPVLO-CLA VZCULAR ARriCUI.ATIO.\. 



229 



eter 



I 



the eotto-efaviriitiir or i-homlinul lir/amni/. Tlii* is ilin-i'loil (>lili<(iM-ly iipwnrii, oiit-j 
ward, and iHK'kMaiil Imm rln- rioni mid npjHT a>|>e»?i nl" \\h- lirsi f(icinl i-ariilnM^ 
to the rhoinlxiid iiii|irc~L'<ioii on tlic iiiidur siirlat-i' of ilie uirnT ciwl iil' tin- idaviole. 

'Ilii- inl^rartifH/iir jitirii-i-iirtll'ii/r \:i II tljittciKi) iIim" uf idiitiil llic «nmo etinpe 
»ii(] ^izc- as th<- ian^r nrliculiir rxiriiii-fiit'tht' I'luvu-Ic. Il is iliiiiiK-Hf til Mipu'iiln; 
and lielow, ihickest above. Il is altaclHtl nliftvi- tn the ii{>|K!r iiiid dor^il IxinkT 
i)f ih* articiiL-ir swHaoo of ih<? daviottr and Ik-Iow io the iiinftr ond of rhi- (tar^ihifie 
of the tir-l rih. Hv ihe ailiichmont of iu cm^iiiuli-rfiuv lo ilio ini>iT ^iirliiw of 
the ca)>mIo tlic joint i.i divided into iwo kiiuoi-'hiI rtiritim, of wliieh the outer is 
iIk- looser, and is i"ontiinn-d a iiliori distance beneath the clavide on the first conial 
ennilajce. The Iwo oeciiftioiially coniuiunicaic through a ]>erfora( ion in tlic centre 
trf the lihm-«iriila^e. 

Tile librn-cartilageH and interclavicular ligameni together reprof«nt theefw- 
eternal bone of lizards. 

The uerrr-gupjifif i-omiM fnnn the nerve to the piihelaviiis muscle. 

.tfatrmetiiii. — The clavii-lc earryinjj the r-<':ii>uhi, lo whiHi ihi- ooraeo-clavioular 
^^ nionl.i elosi-ly hind it. may move on ili* inner end as a ivntiv in an upward 
Wid downwranl direction on a sagittal axis ; in a forward and liaokwurd dinsrlion 
on a vertical axis; or, hy a combination of thej*e, a ciremndmrtory motion may 
be nhlaine<l, il) which the <rlavicle describes a cone of which the base is at it;* outer 
end. A slight rotation of the ciavick- on its long axis is also [K-rmitted by which 
ilJt ventral surface ia turned upward :is the arm is raised, and rlcr vernd. 

The fibro-cnrtilage serves as an clastic huffiT to break shi>eks and resist itrc-taure 
from the vlioulder, as well as to connect the iKinc- and prevent inward displace- 
ment. The inlcrclnvictilar and rhomboid ligaments are tufeguards against 
iipwiinl dikplu'-c-mcnt of tht; innrr end of the clavicle in depression and vlcvution 
>\i the iirtii, iimi the rhomlKnii li<;unK-nt also resists lKickw»rd displacement. J 
When oiii' crliiviilc ix niNch <k'prr.s«cd the interclavicular ligjmient draws tlie 1 
other one u[> — a fact to be rcraemljcred in fracture of the bone. In forced 
depreiwion of the clavick- it pre»K's on the lirsi rib, which acts an a fidcruni, so 
tiiat thi' iiiiit-r cod is raiiK-d ut»d it^ ligaments arc put on the etretch. 

2. The Scapulo- clavicular Articulation. 1 

The Acromio-eUvlcnUr Joint !:» an nrlhrodtid artienlatioi) bclwwn the bevelled 
outer end of the clavicle and ihi- inner margin <>f tlio acromion process, in 
which the ixmes are held together by a i^iiiiicwlml lax cii(tsiilc, which allows 
some play between the surfaces. The <:a|>sulf, wIiom- fdirc" pa** fn)m the acrf>- 
miou inward and frackward, is e--ii>ecially ftlmng aliove, fanning Ihe mpa-inr 
acrmttiii-i'lavH-uliir li;/iimetit, and is here also slrengthenc<l hy tin- (iiwia of tli« 
tfiilM'zius and deltoid. The interior pail, iiit'rnoi- lifiomeiii, i.i weak, n--> i.-i alwi th« 
p.«tirior. The -rifn'jrii'l cavity is sometimes partially, rarely completely, dividtnl 
into two by a small wi^lg»'-«ha}H-d intrriirt!iii/iii-jHjro-rriiiilat/f,allav]ied by ils imse 
to the superior lig-ament, and usually oivnpying ilii- iip|)i-r jiart of the joint only. 

Th« Coraco-clavicular Lixainent, which binds the clavicle to the coracoid process 
of the M^apuln, is the stron)^st connceiion Wtween the clavicle and scapula, and 
Voii!>istf of Iw I) (Kirts : ( 1 ) The conoid Hr/ftnurnt. tlic dorsid and internal fasciculus, 
is u "trting triangular Imtid ;itlin-lK-d by itn aju'X to the inner and hack part of the 
riMH of the roniciiid pmccKs, fmrii which it* fiiircs spi"ead upward, backward, 
and onttt'urd to and nlimil tin- i-imoid jidxTcIc of (he clavicle. (2) The Irapfzoidi 
lufiiment is ihe Bat, ijiiiidtilaHral, outer and fori- part, whow fihrcti slojie upward, i 
i^ckw'anl, and oulwanl from llie npjMT riurfiice of the doTval'half of tiic eomcoid 

Eroce«s to the tra|>e»>id ridge on the under surfair of the clavicle. A tniall 
ursa often exists Iwtween these tW" ligitmenls. 
Filsmenla from th« circumflex and Mipn^aipidar m-nr* mipply the joint. 
Xownmh in t/i« aurotaiit-rliwii-iilnr jniiit mav take phu-i- on a ixriical nxia hy 
whivh the glenoid cavity is turned tarlhcr iKickwnnI or forward, tiiuM enabling it 




230 



THE ARTICVhATIOXS. 



eoH«ll» LIOAMIHT 



til k«]i it* Miilivi- [HM<.iliiiii in forwnnl or ImckwimI nmvpmciil, rr»[KTlivcIv, wf 
tiki? HliiiiiliU-r-^ir(n<-. Or movctiK-nt may tnkc pluot- iiti n luir'aunUil iixiiL, \>y wliirli 
tin- ylciioiil niviry is lurmil t'iinlup iiiiwiird or duwnwiinl, iL-« wln-ii llu- nnii w 
nitni'd or liiwvriil. Tliis ni<>lii>n, ioml>iiie<i with (■It-valion mu) d(|>ivi»i<ni nl' tlit- 
clavicti:-, i^ s|Hik(-ii (if il- nJfiti'iu uf tlie i^tijuitii <>i> a diir-ii-Vfiitiii! axi^ |i:i>5i»j; 
tlirougli its ii-rilri' or iw inipi-r anali-. Tin- nioveint'ni.H at the aui'iiiiiioi-l.-ivk'uiiir 
joint, mndilving the relation of the wapiila to the clavicle, rarely tiiko [Amv by 
themselves, tuil only in wmnectjon with the movements of the sttrno-olnviotilar 
joint. In the combineil movements of llie clavicle and »cnpula the niovenientii of 
the scapnia are restricted by the ^hapc of the chest-wall on which it lii^--, so that 
its principal movements arc upward and torwanl, and downwanl and backward. 
In the above niovcnicntK the vcrtobnil border and the lower angle of the scapula 
are generally kept in contact with the thorax by the muscles attached — a cootliiion 
allowed only by tlio aorwmio-clavicnhir joint. The conoid lignment eiispcmU the 
ticapnla from the cliiviiilu ; thf tnijteicoiil iii tightened when the shunldcr ik pressed 
inwanl. 

The LlBaments of the Scapula. (Fifi. ^"i")- — The (.•'•rurtt^irrominl litfnmmt is a 
flat, triangnliir bund attached by itr* liniiiil biwc to the outer border of the cnracoid 

liroiNNS and by ils blrnil a\wjx to llic tip of th« 
Hcii'mioci. Binding to^^'ther the ucn^nion und 
ronicoid priveiwcB, it fornM an «r<4i ovpr the 
flhoulder-joint xvhich hold* oil' the dclloiil, iiik) 
fnpports and {iiott-cin ihc joint, it.'* vcnlrul 
nnil dor.-al nlnrgin^ aiv thick and Htnni);, 
lejiviug a thin mt^mbiiinoiis part iHlwti'n, 
with often a gap near the coracoid priMt-;**. 
The deltoi<l covers its npju'r siiriaee, which 
also looks a little forwanl ; its lower surface ia 
poiiaratrtl bv a bursa fi-oni tlto capsule of llu- 
shouldcr-joint. Fiian its outer edp-, which 
projects over the centre of the head of iht- 
Qumerns, n thin, tough fiLsaa is eontinutxl 
under the deltoi<l and over the subacromial 
bursa and the shoulder-joim. The iratixvfT»t\ 
coraco-acapiilar or mijitv^ieapu/ar lignmefd, eon- 
iinuing the upper border of the scapula, 
bridges across the BUprai^c^ipnlar notch, converting it into a foramen, thivmgh 
whicli Ihc snpnii^ciipulnr nerve pas-es, while the corrt"i|>onding artery commotily 
jMiwes above it. It i» thin and Hal, and is sometimes replaced by bone. The 
tj)itiO'fft'-nrn<l liytimriU et>m|>riw» a few la\ fibre* which, by posting between the 
outer bonh'r of the i«pine and the margin of the glenoid cavity, bridge over the 
iiupni.-aiiniliir vtiwels nml nerves in pii.-^sing between the >»i)ni- and infruspi»uti» 
fo»*a*. 

3. The ShotUder-joint (I-'igs. ilS-'ieO). 

This ball-and-^iiH'ket joint, between the liirgi- himicnil liead and the oniall, 
i>lmlIow glenoid envily of thcifcjipula, ii^ one of the most ]R'rfeet and niort movable 
of jiiinl^. The ^nrrouniliiig muf>clei< give strength and wenrily lo the joint, and, 
togi'lher with atmnsphi-ric pnwsnre, liidd the Imnc* in position much more tlum 
d<i the liganicnlH, The glenoid fo.v'a is <lee])eneil bv the i/fenui'l (igamyit. tri- 
angular on section with the ba--«f atrachcil arnund tin- margin of the fns^a. It is 
eomjHwd of tibro-ftrtilage with wattrri'd eartilagi-cilU. To its np]MT end i« 
attached the long tendon of the liicejw, which, ilividing, is continued into both 
aides. Outside of tliis ligiitucnt the ftiji«uftir ligommi is ntliiehed to the >K.-iipuU 
around the glenoid margin, sometimes reaching as fur il* half an inch fmm it in 
fruDt. From this attachment it [Misses to the anatomieal ii<-ck fd' the hinneruif. 
At tltv lower and inner |iart of the latter it is attached »onw <lit<ta>ice fVum tlic 




Fin. KT.-Olonnld Ibna «f rlgtit iMe. 
(Tertuil 



I 
I 



THE SHOVI.DKn-JOIXT. 



231 



HriictiUr siirfiinp, And in front, iM-iwi-fti lite lulH-rtk^itk.i, it i'ovcr<^ ov<t nn<l \* 
iittiiolttil 111 till' transverse lij^inK'nl, thiw ^ving i>jL«igi' In the innj; U'lirlon nf tlw; 
hitv[i!». Till- I'MjiMile is r^HnjK<^i>(| iif longitudinal til)rfn, with i^ome oblique niul 
riroiilar fibren inttrwovi'ii, and is strongest on ila diipt-rior asiMfet. It is so lax 



■VH*IOa SKHO- 
LKUVEHrf 




Fin. ^^•S.-HbouId('^]olnI. retr tIiw, Tbc lund pan of the ncniilar tlEniD«nl miil nitwt of Ihc h>*'1 of lti» 
bttnurai liavc Iwcn nxM/vtA. (TntuLj « 

tliiit tilone it doc.1 nol kt'ep tin- iMine.^ in coiitaet. Above and heliind tbe tt^'ndons 
of tito .'iiiprs.'iiiinntns, iiifra^{>inatiii<, and teres minor, in iVont ilial of the sub- 
^eapularLs ana below the long head of the trice[>s are intimately eontnTttil wiili 
ana Mrengtben the capsule. Between the siibticapularit) and trieep tfnduiis is 81) 




na. 2K>.— Sl)'iiililur->>liil. frnol *1vw. il.-ini i 

unprtrtwU-d and weak |«trl of the wtp<nle. Ttti* is the part nMintly torn hy the 
pHOMii^! of the head in lUslocalions. to "liiili tin- shoidiler is very liable, owinjr iti 
|»rt to the l<Hweiief>« t>f itn <",i|k>ij1<'. iJesides ilie overlyinj; temlons the eapsule 
Imw Iwo sets of aoee.-wory fol<K 

(I) Tl(e eomco-liiiiiural Hffnmrnt extends as a wti-on)r, broad band from the 
outer border and root of the eoracmiil pnieess, beneath the comeo-aeroniial la- 
ment, obliquely over the yiint lo the anatomical neck of ibc litinierns above the 
great tuberosity, being intiinatelv eonneeted with the capsule. Seen from in front. 
It appcant a» a fan-shaped prnee.s^ lying «ver and above the capsule, willi winch it 



232 



THE ARTICVLATlOyK 



u]i)K'iiiv coiitmiKiiiis !i^ vicwci! rriirn brlniiil. Tliiw lijrament represcnls a (lrtach«l 

Kurt i>f tlic [Kftonilii' iiiiinn- ti'tidcjn. ( 2) llic 'jlrun-ltHnia-nl Oandn. thrcp in nuni- 
iT, cxrciicl lii'lw.iii liu- v<-rili-:il niiir^iri of iIk- frlciinii! ftD^ta find rlii- iH>ck of ilie 
hiimi-riiK. Thvv nrc mh'h priiji'Cliiij^ ini ihi- irilcnor ot' tlio intUT juid fore ohm of 
the riiiiT-iiii- w lu'ti lliv joint i.-* rtjH'iK-d fmin Ijcliiml. Tln' >"'jiiriW i/lnio-numert»t 
huiut c.Mfiidn ImIwh-h tin- iipiicr riid 'il' lln' vriilrul niiirpiii i>t' tliv j^kiioid nivitv 
and the. upinr end of t]w sniiill tiilH-nwily of llic liiinu'niK, foriiiirig u »1if;lit 
gn>ovp, din-cled backward, ("i- the hmor edj^^ of tin- biit-iMt tendon. It nmv 
octahionally be quite free from the eapsiile, and it li<^ above tin- n]K'ning bv wliirh 
the bursa bcneutli the subscapulans tendon cominunivatos with iIk- synovial 



4 




I'm. sm.— HhM]Ii]«i-J''tB( In coronal icctloo. front vl«ir. The ayiioTlal me l> itltii'iKlviL iTmiuI.i 



cavity of the joint. The miil(Ue. </lfn<i-humrml hunit lies btlow thi^- opening, 
alon^ ihe lower borrlcr of the .siib.-<rn|)ul:iri^. It unset' from tbv glenoid mai^in 
with the sn|>eriDr hand. :uid \^ altaelii-d to the inner Mv of thi' Miiidl tubcrofiity 
of tiie humerus. The !iif'i-i-!or (/Inrj-lnimrraf />oio/ is the slr'niju-sl, (itnl |in"<« 
In'tween the middh' |iart of the ventral l>order of the frhnoiil rim .-ind ihi- lower 
part of tho neek of the hnmenw. The superior (ileno-hiimenil band ivprcwnlii 
the divorced tendon of the siibclavius muscle a» so<'n in l>inl«, and correiijKiiKb' In 
llio ligimienluni teres in the hip. 

The frium'crsf Hjjinnent, l>y nieune of its Rhnv \iammg tninsvePeiely lietiveen 
the liiliiTOKitii-)-, forms a eiinsd of thsit ]iiirt of Ihi- bieijiilnl uroove which belongs 
to tho e]>iiihyM*. The eapsnlar lifpiniiiit is :illiiehi-d to il ;iU|M-rli<'ially. 

The ttipinriiil mrmf/iiTiir lines botli free >nrfaee_i of the jjh'noid ti(piment, and 
ifi n-UccIfd thence over the inner .larfiiue of the capsule to the humend neck, 
wlii'Ft' in fnmt it piceieM down the bicipital eaiial for a (]i«tnnce, and there is 
rpfleel«-d onui the bieep^ icnilon, which it >henlhe>, an it iiaswes through the ji>int, 
ss far it» ati;ichmeni to ihi- jjlenoiil lipimeiit. l!etwi-en the (.iii»rior and middle 
jrleiKi-hunieral hand^ there U ut.nally an o|M-nint; wlierc the f.ynovial inenibnine 
in cfintiniionii with thai lining the bursa beneath the ^ub*;ca]>uhirii^ tendon. It 
oceasionully comniuiiieates with a biir^ beneath the infni»|iiiiatus ninsele. 

The articular cariilape is ibieker near the centri' of the head on the hmnerus 
and Ut the margins of the glenoid focsii, thus dee)K-ning it. 

,\V/TW from the snpnivt-Ji Hilar. eireuniHex, and snbseapulur sup]ily tho j<iint. 

Movmuriili'. — Flexion and extension, iibdut-tion and ml(hietii>n, riitiinnhii-iiiin 
and rotation an- allowed to u dcgni' di'terintiu'd i)y the extent id' the hnmi-nil 

artienliir snrtiu'e, the leri^lii of the eap>id('. and tiie resistaii f ttie overlyinj" 

parts. Flexion and i'\feni«ioii, or the iimvcmeiits I'orwaril mid :«lighlly inwnrtl, 
anil backward and sli^lilly uatward, lake place on an axis eorii'S) Minding to that 

of the head and t k of the hnmeru.-<, which is nearly per|H'n(Jieiiuir to the centre 

of Ihe glenoid cavity. Flexion is mueh more free than extension, and between 



THE ELBow-joryr. 



233 



tlie «][(n-inc» i>r Imtli rlti^n- >.■• nlmiil !>0° of nKiliciii. In alHliiclioii iiimI a<lilii<'ti<in 
tho anu Dinven awnv frmn or touartl tho luxly, pes|i«H-livi-l_v, mi ii lionzoiitiil nxU 
ac rigitt nn^Ie^ wi'ti ilial lant nanunl, aiul jimmllt-l lo iIh- Hiirlai-e ol' tlio irlt-imid 
f<e»a. Ill csln-iiie alMiiH-iinn (i, c, t« aljiJiii DO") nr fSlPiision the (frwil liilnTiwiiy 
strike!) n^iiii^t the coraco-itrromial liKanioni and ihv :toi-omioii |>n>ecw, and f nrlher 
mminn is thns limiUHl. The Riviit frewlom of tnotiuo at the fhoiiUW, l>v which 
thi' arm can be raided tn* .-w In W iirarly vertical, 1* in purt due to th* movement 
of (he sen|iiilu. u lii<-h nlw3i_\> iu'iTmii(Kinii> niovenivnts nl thv 4KHiUhT-ioii)t. lloth 
abiiiK-lion and Hexioii over JiO" are line to rotulion of the >4-a|iula. hv nhieh llie 
glemiid cavity is liirii"! "iitw:inl ;iiid niiwani, or furMiinl nnd upward. Uot:it!iiii 
oeenr* tii an outwuni (or liHckwiinl) ami iii an inwarti (nr lorwaixl) direction on ait 
axis dmwii from thu centn- of ttMr hi-ad to the inner txuitlyle of the hiitiienis,and 
over B ninp- of lK'tw*i'n &l>° and \iW. \n extreme alHlneiion tlie lower jmirt of 
tlir caiwtile is leiiw. In uiitwanl rolitlion iIk- iiimeo-ininieiTii li^^iment is ntndc 
tetiM', and in {mlh iiiwani mid onlu'urd rotation the njiper jnirt of the <.ii[)Mite \» 
ti[rhtt-ji(-il hv IwiKlintf. 4.>tli<-rwine, ihi- niiiM'leta nilher llian the lipinieiilii nvtmin 
the tnovemi'nt.4. In dinlivation ihi- conioiolniini-rnl li^riinient i.-< thoii^lit lo Ih- 
im|»irtant in deleriuiiiiii)f tlie position of die dinliK-aled limh and (lie mani|Milu- 
tioQ for ittt reduction. 

The mtbacromiai bursa ]ws between the joint-eapsule, with its attached ten- 
doiLi, and the arch forine<i by the eorac<^>id and acroniii)n jiroivsMs and the coraeo- 
acroniiai lijifnnicnt, and it also extends benenth the deltoid iuii>K?le. It facilitates 
the mo\eiiieiit» of thi- upper end nf tlie hiinicrits. The coraco-acroniial aivh 
fi>rmf< a i^ort of secoiKlary socket, ag»iii»)t which the head and tnlwro^itic)* of the 
humerus arc pruned when the weight of the body is supportiil by the arms. 

Thi; hicept; teiMlon acts as a ligament of the joint, preventing; the hnineriis 
from U'iii); pulleal np forcibly af^aini^l ihi- acromion, ami Uecpinf; the lieiid in the 
vli-noid :«H-kci, c.'<[Ht-ialiy when the ann i^ away fmm ilie side of the body ntid 
t» pulled down by the [K-etonilis major and latissimus dursi muscles. 



4. The Elbow-joint (Figs. 261-283). 

Tills is a true hinse-joint lietween the trochlear surface of the humerus and 
tliv ii^rcat sifcmoid cavity of die ulna. It is broadened. :ind thereby Accured against 



■MTIII»>ttOW* 




Tta, M,— KlboW'JolnL.nwcUl tii-u. il'uirivr.i 



Iat4-ml motion or displacement, by die artienlalion of t)»e np]M<rend of the radius 
will) the oapitclliini of the liitmcrns. To the shnjte of the Imne-t i.i due the 
stniiglti aiul seiriirity of the joint. Beneath tlie eiirroiinding mu!«lea nnd ten- 



234 



TSE ARTJCVI.ATIOX8. 



doDH, which furtlier .Htren^hea the joint, liea the fibrous eapsvie, reiDforced inter- 
nallv and extenialty, ami ihewfore doBcribed in four irartfl, 

riie ti-iaiigiilHr inlenmt Interal ligament \6 attaf»€<l l»v ito apex to the lower 
aspect of the intt'rnal cDndylc, ami liy its Imw; to the inner margin of the comnoid 
and olirrsuion |)nH.c^M-K, It it diviilid into two ^nialk-r triaiipk's. ventral and 
dorMul, b_v iin intfrnndintf ihlrntiT |nin ullai-hi'd to the iiKvtinf;-l>oii!t of these two 
procci'W-s. Thiw lij^nm-ril is the »li'(ing<-.>t {iiirl nf llii- (■»|>sidt', 

Tht^ Ktti-rniil hiUrat lit/iimtnt, shorter nnd nurrower l)mii the internal, radiates 
from it?' uj)tier iittachment on (he lower part of the exii-rnal non<lyle to the 
niiter side of the orbicular lijcanient, A few (iVires reaeh the mi-k of the riidini-. 
The anterior fitfanteiit in the tliin, fore part i>f the eaiwiih- between the lateral 
ligaments. Siimrrifirly it if. attached above (he eoronoid and radial deprt-s.-i<MW, 
and inebides ilieiu within the joint ; iuferiorly it is attached, jnst Ik^yoml the 

articular inaf^in, to the front of the 
coronoid proceas and to the orbicular 
ligutnent, some fibres ^mssin^f to the 
neck of the radius. It is reinforced 
by the adhesion of some of the fibres 
of the bnicliialit-, wliieh draws it up 
in fti'xiiin am] pnvi-ut^ It fi»ni l>eiug 
nipjM-d lH-lW(*cn tlie Ixmy niarierin». 

The rjiM^rior li;/m'ifiU it^ thin iind 
weak, like the anU-rior. Hy it» iit- 
tacliment abovf and ut thi- .-ide« of 
the olecranon foMf^:i it inelii'df-i the 
latter within the joint. Its iipjier 
librea pa** transversely acro^is the 
fossa. Inferiorly it is attached to 
the olecranon process, near the ujiper 
and outer margins of the great sig- 
moid cavity, to the orbicular liga- 
ment, and to tlie ulna behind the 
small figoioid cavity. It is strengthened by the adheeion of the triceps, whtch 
draws it up during extension. 

The synoviat membrane lines the inner surface' of the capsule, and lhcnc« 
po&ses onto the humerus, where it lines the oleontnon, c-on>noid, und radial fwsae, 
and cxtemis to the articuhtr enrtJIage. I'nyeetiiig into the almve fu««R are 
musws of fat placed betwwn the eiqwnle and the synovial ineinhrane. Inferiorly 
tile nienibrune e\ien<I:< into llic .iniN-rior nidio-nlnitr joint, wliert> it liiie^ tlie 
orbienlnr ligaitn'ut, thence pa-sing onto aii<l anmnd the neck of the mdin*, and 
m lip III its nrtieuhir cJtrlilage. .A fold of synovial membrane, pnij<«ttng into 
the joint from in fn>nt jipjMwite the outer lip of the trochlea, suggests the divi.sion 
of the joint into two parts. 

The luvrf-Hiiji/ili/ \r. mainly fnmi the tnusciUo-cutaneous, with a few filaments 
from the inuKculo-spiral, median, and ulna. 

Mopcmenta are c-onfined to flexion and extension on an axis oblititicly placed 
at an angle of about ^4° with the ^haft of the hunienis, so that in extension the 
foR'urni is inclined oiitwani and in fioxion innanl. Flexion occurs through 140°, 
And is limitti] by the e^mlaet of the soft, partu ; extension is limiteil, when the uln« 
nnd luniieruK nre nearly in line, hy llie tension of the s*ift (mrts and ligitments in 
froiil, and of the v<-nirtil jmrlions of the lateral liganient>. The olecranon and 
niroiiiiicl |l^H^es^t■s ilo not arrest normal hut <mly fiircinl motion, by eontaet with 
the bottoms of (heir re»*|>rflive fosste. The lieaid of (he radius moves on the 
eapili-Uum, and is in most complete contact with it in seiniflfxion, in which p<wi- 
tiwn it rotates l>est on the humerus in pronation and supination. Exf^-pt |>as- 
ably to a verj- limited extent, owing to the slight incongruence of the surfaces, 
lateral motion is prevented by the lateral ligaments and tlie shape of the bones. 




FlQ. IVI^.— ElbiiW'Jiiliil, uiiUrr iililti. <Tntiit.) 



RADIO-VLyAR ARTICULATIONS. 



235 



Wlidi ttu' cIIm>w ill «'xt<-i)<lc<l tli(^ tip of iho ol<>craiK>n lies on or jii=t Im-Iow il 
liru- coniK-viiii^ liie lwi> (xni<lylc^ : u'li<-ii fli^xM lo a ri^lit angle it lice u lictlv mora 
(hun tmt: inch ttcHow, uikI iiiiilwity iM'twcen thew two |H>iDte. 



««»Gvuta. 



5. Radio-olnar ArticulatioDS. 

Two jointe and an int«rm«]istc fibrous union conne^rt the ulna HDd niditis 
firmly topothi-r. 

(A ) The Superior Rftdlo-alnar ArticuUtion. — Tlit^ rim of th« hfoiU of the miliu* 
is hdil in <i'iil:K-t with tho nnmW )'i|;iiioiil cuvily 
of the ulna by tlic slnnij' fiicinrling 'u-fiifu/tir Ug- 
ammi. T\m forin?i limr'IIt\)iN of a nirclt- uiul m 
attachf^ to llto vcnrriil unil dort^nl liji.'i of tlic 
MRiall tiij^motd oavity, whirh (■i)riii)lGtes tiie ring. 
Il form.-i pari nf (he pajwiile <)f th<' ellmw-joint, 
and in.Horted into it are the external and \KUia 
of the ventral and dornal |»-irtion--t of this ca|»iule. 
lu lower border tighily girdles the neck of the 
radius. Frotn this border membranous fibres 
pa^a to the neck of the nulius loosely enoudl 
to allow of rotation uf the radius on its long axis, 
It is line*! by tj/n'n-iof mrmljfanr cuntinnoiis with 
that of iho flliow-joinl, ami iis nrrrf-Hii/ijil}/ is 
derivc<l fmm liiiit of tin- I'lliiiw-juinl. 

(B) 'I'ho Middle Radio-olnar Union tn ao<-om- 
plished by two lipinuntii, (11 The Mlquf fig- 
amenl i" a flaltetieil Imnd, which pae-es obliquely 
down wan! nndoiit^'^nl from the lower and outer 
part of the tuberosity of tiie ulna, at the base of 
the coronwd proci-**, to the radius, dinx-tly bi-low 
and behind tin; bicipital tuberusity. Below this 
liniment i* a *]iaoe throuph which tin- i)ostcrior 
inicn>^'>«iiiL'< ve-vwW pa.**. Thi.t «pai;c in bounded 
bcliiw by the slrotij^ (2) hderoHxmun mfmltftinr. 
Till? fibres of the taticr iwss ninslly oIiIiqu<.-ly 
downwiiM and inward itxmi the interosseous 
bonier of the radium, commencinp about one ineh 
below the tuberosity, to the whole length of the 
interoa!*ouB border of the ulna. A few fibn-s on 
'»s doraat siirf:iee are pai-nllel with the obliiiue 
li^nient. decussatinR with the other fibres. The 
inlero«si'ous i-jHice is widest in the middle third, 
and i<^ wider in siipin:ili>.>i) than in pronation. 

(Cl Tiii^' Inferior £adio-iilnar Articalation, between Ihc sitnnoid eavity of the 
railius and the hiwer end of the ulna, is sejiarated fn>ni the wrist-joint by the 
triitu'jufiir fibrn-^iirtiloge. This thick phuo is the most ini]>urtant stnictur*^ in 
thi- joint, not only as (he stn>np-st l>ornl of union bctwivn tin- two bones, but 
aW in liiuilinjr their movements. It is nttaelie*! I>y it?" bnsi- to the mnr^n of the 
radium, whieh M-|iiinites the ■■t(jni"id «ivil%' fn>m the earpiil Jiu-el, and by ittt apex 
to the fix-vsa al the Imse tif the stylni<l proeeKs of the ulna externally. This car- 
tilage Hi-|>araieN the lower eii<l of the ulna, which n>st» un iu npjK-r nnioiitli, eonrave 
surface, from the cuneifunn bime of the corpus, Sane seniten-il fibrpji from tlie 
two ends <'f the sigmoid envily of the radini jiass to the ventral and dorsal sur- 
fiieoa of the hiwer end of the ulna aWive its iirtieular suribci-. They are cidied 
anleriiir and juiMta-iiii- ra(Uo-vlnar li(fainciit>^, an<l are emnneptMl with the bortlers 
of the fibr"i-<'ariilage inferiorly, ami with the interoseteoiis membrane snj>eriorly, 
thuD completing the eapmle. Lining the ea])«iilc is the eynot-lal membrane, which 




Pin. i-Jx.—CllH.w -Joint In ilKlnal N^ 
ll'in. thi'wlnic Itu' HnlruUr VTnOVlat aM 
and tn« buna uf Ih* olvcmiun uid Ui* 
blurs*. CToratJ 



236 



THE ARTICULATIONS. 



is rrmurkably loose. Ro-«iiloH fxrontlin^; upward brtwfen ihe radiux and iilim, it 
lirwBf th*' upjKT Kilriiuic of iln- rthrii-wtrlilrifrf l>fiK!itli llic ktt«T, 

The nme-Jiii[iiift/ iif thi' ttifi-rior nulio-iilnur joint conies 
from Uio aiilcrior .iikI [MwtiTii>r intcnj^cous nerves, 

Mot^rn\nit». — The upper emi at' llie nidiiis rotates on a 
lo»]{itii(liual uxiii [tassin^ iliroii^i '»!> luwliind ncc-k, while the 
lower end rulales around the hend of ihc nirm. having t!»e 
Httnclitiicitt of tlw apex of the film>-f»rtiliip' ii» its pentre 
{Fid. 2»i4). The enliri- bone thus de.-erih<-s nithcr les* tlian 
!«()" of II com-, with its BjK'X abov* iitid its irax- below, its 
axin exicmlitif; from the ei-iilre of the radial head to the outer 
side of the styloid priKx-K" of the ulna. In the!*e movements 
the radius earrics tin- hand. The forearm is said to be "iipin- 
ated when it» two bones lie nearly jMinillel and the dnisiun of 
the band looks luiokward, and pri>imted when the radiuK Ii<>8 
obliquely ncnijw tlie nlna, and the jNilm of the hand looks 
backward. 

Tiie power of supination h DJUeh jiTvater tlian that of 
pronation. In the above niovcmeiitji the ulna is thought br 
many to undergo slight cireumduelion. This impUeti a little 
hitenil movement at the elbow, whieb. if il oceurs at all, 
nitist Ik.' very trifling and due to a slight iueoDgriu'ui'c of the 
BUrfhw,*. Supination and pronation with n »tniipbl arm are 
appiirenlly inuih inercusi'd by the nitation of ihf humenis ut 
tile shoulder. The iuterosseuuD membrane, from the direc- 
tion of it.Ti tibres. transmits the weight of the IkkIv from 
the ulna to the radiu.« or tbc «hoi-k of a fall on the' hnmU 
from the radiiL* to the ulna. 



tta ej prtRiBtl'in Mid 
■UplfWUuD. tTMlUl.1 



6. The Wrist-joint or Radio-carpal ArticulatioD (Figs. 

2Ho. 2'IG). 

The lower end of the radlu-' and of the triiiugular fibm- 
<;anilage presents u surface slightly <Hiiie«ve tnmsverseiy, as 
well as from before bw^^-kwanl, wliich reecivcs the eorresiKindingly convex iipjicr 
artieiilnr surfaw.s of the !««iplioid, semiliiimr, and cuneiform bones. 'Ilie latter 
ifurfuctv an- pn>liinge<l liirther iijhiii the- doi-^al than upon the fulmar a.'«|>ecl. Tlx- 
uliin is t-xchiditl ri'iiui iht- joint liy thi' triangular earlilagc ; and the pisifonn Ixiiie 
of the first row d(H-> not eiiit-r into tin' articulation. The joint is eondyloid in 
action. 

The rather hiose aifinule is deserilic-d as four ligaments, whieb are, however, 
continuon.s. The intrrmil latei-af flifaotenf is attached above as a rounde<l cord to 
the styloid ]micess of the ulna, and i-pi^adB out below onto ibe cuneiform and 
pisiform bones. The eA-trmni fatri-at ti^amcul nuliatew from the Kiimniit of the 
radial styloid procesu onto the outer, back, and front surfaces of the ocaphoitl, some 
6bres Ix'ing continued to the tnipcziiini and o" magnum. Il is in relation with 
the radial artery anil the extensor tendonc of the thumb. The ntilirinr /iwimrnf 
is brojid, sirong. and nicmbninoui>. Its ^brex paw for the most juirt oblic|uely 
from the anierior border of the hiwer end of the radius d«wnwt«nl and inwanl to 
the juilniar l1^[M1'l of the sejiphold, neniiluimr, and cuneiform bones, esjM-cially the 
latter. .Sinie fibn^-. \ia.-v over to the os magnum. AnothiT group of fibn-s ))(ts.s(w 
Wire vertically from the ulnar styloid pi-oix-ss tothe si'mihinar and enneiforni Ihuh-s. 
The fimterior lif/fiin''nl, thinner and les.s strung than the anterior, is strengthened 
bv the extea^ir tendons in relation with it. Its fibres also pa.ss for the most jwrt 
obliquely downwani and inward from the don^l bonier of the lower end of tlie 
radius to the linit row of eargisl b<me!>, esijecially to the cuneiform bone. 

The mfnorial niembrane lines the eapsule between tlio articular surfaces. 



THE CARPAL ARTICUI.ATIOXS, 



7. Tbe Carpal ArticalationB. 



2S7 



The bnnc!! of eoch of th« lwi> mw^ of tin- i-ai'im.-, cxoliisive of the pisiform, 
are c-onnectwl tf^ther liy dorMil, palmnr, and itJfmmeous liffamettU, pairing 
marly tran^v*^rs«>ly between atl)nci?nt boncH. The |Kilmar arc stronger titan the 
dorsal li)n»ii*-'nu. 

llie Joint between the Pisifonn and Cuneiform bones is arthrmlial, ami ha^ n thin, 




fw. 3Ml— The aitkuUtltnu of Iht^ratput. Tti* fimiivliil um are rc|iHiiaiil*>l iw dltUndcd. iTntul.) 

loose rapgute lined l>y ft/im^iil mrnJtrttnr and atren]i:thfne<l by a fibrotia band 
pa>«in]; lo the hook of ihv iiiioifomi, by another passing' to the Imsn of the fifth 
mctiK-srpu), and by th<; iiisi-rlion «f ihc tendon of thp flexor rarpi ulnarial 
from iiliovr. 

The Uedio-carpat or Transverse Carpal Articulation. — This joint is lictwoei) 
Uk- hjwcr n*|H'Ct of tin- fin«t i'ar|>!il mw, which ik coiieave except f>.r the eonvcx 
oulor ]>arl of the wiiphoid. and tbe uiipcr ."iirfuee of the second earpul row, con- 
caviMKtnvox fn»m wiiliont inward. It is unit('<l by ihrnn! and p<umnr, ttitrrnal 
and rxta-nal laiertif ti^aaurnlK. The lateral Hffmnri'lt. pniloiifri'd from thi? lateral 
li^menlit of tlw- wrist-joint, coni}rcf the lati-r.d siiHat-e!* of llie oiit<-i- iind inner 
bonei* of the two rows. The dor*af {l</amfnl» exu-nd nbliijnely Iwlween the dorsal 
surfaoes of the bone.s of the two rows. The atningi-r fiutnuir Hymwnfi are com- 
pnsefl of fibres whieh for the most part radiate from the os niagnnm to the bones 
of the upper row. 

Tbe tynopial mnnAmn« is cxteiiKive, From the medio-oarpal joint it sends 
two procesjies iipwarrl between the three Ixmes of the upper row (exchisive of the 
pisiform) ; and between tbe tour bones <)f the lower row it sends three pruwwes 
iliiwnwaril, which nre eontiniieil into tltr four inner earpo-metawiriMil and the 
three iiitrrmetnciir)Kil nrticii hit ions. It is nearly ulwayn sejniruted from tliat of 
the wrist by the intero>*euns lit^amcnts which pa-^s Iwtween (he bones of the upper 
row. nnd make their eonvcic upm-r surfjiees uniformly even. 

The n^rrf'totj>phi of the rmlio-<'arp(il and vnrpal joints is from the ulna and 

lian in front and lite |>o»terior inter<j!<«coui( Whiud. 




238 n^Dir THE ARTICULATIOXS. 

8. The Oarpo-metacarpal and Intermetacarpal Aittculations. 

The pntximul i-mlri of tin- iiim-r i'oiir iii('tii(-jir|itti bi>rii-snrf uiiiu-rl tu the innet 
thrive Ik>iii-.s cif the Idwi-r mw ni' tlic rariiits by ilorwil mikI |vitlnmr lipinictiL% Of 
tilt: doiKil lu/itnuritlM the sttcond »ii<l thinl intttamrjuilH rf(;i:iv<; two ur thrMi vuch, 
tho fourtli two, anil tUc. Rttl] oiu!. Th<: latter ih t^ontinuous inU-rnully with the 
jialmur li^piineiil, fonuiiiK a partial capttute bt-twecn the iiiioifonii and the fifth 
mulacarpal, opi'ii txteniallj'. Tlit- palmar ligamenU are weaki-r and lc*»f Oi-lineil j 



IKTCflNll. UTtaai^ — 
WOantHT 







Fw. 3H,— UfunvDU of th« Mtpiu. IhiM Tlmr. rTcMat.) 

the third metacarpal recfivps three, the others one eaeh. An inlcrogsemi* f*fff- 
mrnf !ilw) eonnecl-i the eontipnoiis hiwer anplei' of the os mugniitn and the nncifoim 
with the inljdnTil srirtiK*» of flic third and fourth metacarpals, i>e<-ji«Tiiiml!_v I'htit- 
ting oil' (lir Kvnoviiil KHi- hetw'i'cn the inner two nirtacarpaU and the unciform 
from tlie eomnion synovial hik-, whieli is cuiiliniioiis with tliiit of the ejiriuil jointic. 
A strong imud fi-oni the traix'/auin to the outer a.*|>(H't of fiie iwiso of th<! MfOtid 
ra«tfl<!arfial Iielps ti> elose the nidial side of the joint of the latior. 

The ha.-et< nt" the Inner four meiaearjial bonc!' are bound loj^-ther by 1raii--vi-r»4', 
pnliiuir, iliirmil and inleronnfoiis llf/atiiatif. Their di.-ital ends an' Hnitwi by (i-an»- 
verse flhrft* passing between the mar)rins of the jialmsr or glenoid ligaments of the 
(netaenmo-plialangeal joints, and forming the frangverite metacarpal /igament, 
whieh limibt the i§e|>anition of the metiinirpii! bone^. The fin<t nietaearpal l>one 
is free from the others at both endi^. In the v(irf,i>-mrtnmrpid jnuil of the thumb 
there t» a thick. Iixiw rnpmilr, Htn)ng<'!<l dorsully and externally, which tvnnectK 
the margin* of ibe arlieniiir wirfm^'sof the trti|K-xiiini nnd the first nielueHr|)ul. It 
18 lineil V>y a sejuirate Mi/ituviiif nirm/triiiii. 

Thv nrrvf-mujiiihi of the inner four turpo-inelaeurpul joints comes from the 
(Icrp [lalniar bntni'h of the ulnar, the posterior intt^rtuuteont*, and the inediim, the 
laM supplying al--%o the tirwl tnirjio- metacarpal joinL 

Mm'fmmU of n similar luilnn- ix'eiir in (be rttdSn-r^rpnl an'l vifitin-i^trpat 
jaintn. Thew* uioveiueiits tin: Jirj-hm and rj-li-iixUtn, tiMurtlun and niiilurlion, and 
cirrumdudion. Kxtension Ih more five than l!exion in the nidio-earjml joint, owing 
to the greater extent of the car[)al articular .snrfaee» dor^Ily than vi-ntnilly ; but 
flexion in more free than extension at the medio-eiirpul and ean>o-inetaear|»al j<Hnt«, 
and it is the mope free of the two motions in the wrist as a whole. AlHltietlon and 
adduction, on an antero-posterior axis, occur principally at the radioHiir|«il joint. 
Adduction is mnch the more free, tor the ulna does not extend as low a* the 



METACARPO- AND IXTEBPHALAXGEAL ARTIVVi^TIOXS. 239 

radium, noil iloe^t Dot h«l|> tbr cxtonial lateral ligiimciit to cliei^k addiictiim a» tlic 
nuliiii^ ilocs l\w iiitern:il lateral liganKriil to clicck uljilucliuii, TIk- liicli of r»tii- 
tion in the wri^t k ci>iiipt?RKitc(l ti>r bv the proiiiKiuD uml Mipiiinlioii of the fore- 
ann, in which (he hand rotates witfi the radius. In the medio-rarixii joint, 
besifles vi-nr free flexion, niiMlonttely fn-c extension, und slight latcml motion, 
there is veni' liiuiteiJ rotjition of (\w linui of the os tn;i};iiinii ami thi' iiiK-irorm in 
the socket funned l>y tln' ii|>|mt row, wliile tin- tni|iv/'nim am! tropi-Kniil ulide 
Imrk und forlli on (hi- KCiijilioiil. In iht- ci-ntnil (■iir|Hi-nii.'tiii'^r|i«l jniiil^ llt-xioii 
and extvnT^ion ktv slight. Tliv tiflh mi-nuvirjinl is i-iiiiabli- of nior*- flexion timii 
are tlio spcmmI, third, un<l fourth, and ihU flexion iii dirvctetl onlwurd nn well iu< 
forward, prodiidng iip^Hxiiion, or niirrouing and hollnwin); of the liiiml, iLt in the 
olow**! fif.1. The moveinonU-i of tht- first nietai-arjiai are n-pulaled ]irini;i[Killy bv 
the sudill(><>ha|>e of the rttirfaees, and conwist of flexion ana extension, abdm-tion 
and addtieiion, and eirciiniduction. Flexion is most free, and itccnra obIti|nely 
forwani and inward, thns allowinj; the op]>osing of the thumb to any of the 
finjjery. Abdiietion is also very fn-e, adduetlon le.-w so. Movements between 
bone^ of the same row in the curpti^ are limited to slight gliding, which gives 
elasticity to the caqtus, breaks jars and vlioeks, and thus strengthens the wriri. 

9. Metacarpo-phalangeal and Interphalangeal Articulations. 

The cup-shai)ed basest of tJic proximal phalungcs receive the rounded heada 
of the metacar[ail bones to form a condyloid joint wltosc eapsuU is verj- weak' 
Iiehirtii, where the joint is covered by the t'.\piin>-ion of the extensor tendons, but 
is reinforced lutentlly in fiMnt, The fitmiig ''i/<Tfi/ /Jyfinioi/jt an* «tt«rhc<l lo the 
lHt<;ral tubercles and the depn-jwions in front of them on the lu-ndK <if the laetu- 
■.■arjiul Iwne*, and |iil« downwunl and forwsird lo the liitvrnl margin.* of the liasoa 
of th<> ptiatange.i an<l to the juilimir or glenoid lignnn-nts. The uiUrrior, jKtlmnr, 
or fftmoid ligament is a thick libro-cflrtiliiginoii.* plate, littui'bed elo«(Iy to the 
nhalunx, loosely to the niotaearpal lionc. ft is couiinnotis latei^lly with the 
iiiti-ral lig:inii-nti> and the tmnsvei^e mclacarj«il ligament. It> pidmar hnriace u 
wligblly gniovcfi for the Hexor tendons, the sbciitliK of which :ir*' attached lo its 
luargin.t. Itsdor^il surface 1h'I|is to support the head of the metacarpal i«me. 
In the thumb (and occasioniilly cl«^'wlict^') the fihrct-cjirtiiage o>*-ifies into two 
sesamoid Imiws which reecivc (he in.-'crtioii of ihei'hwrt muKck"" anil form h griKivc 
for the long flexor luii^-le. 

The inter/ilinliuii/r^il tirtirulidmvt Rpo in every wny nimibir, except for slight 
diflei-enees in the sliuix* of the articular nuriaco, whii-h influi-ncf the aetion. A 
ttptorial membrane Wm-iy tin* inner [•urfm-i- of the connecting ligamenl.s of each joint. 

The neree-mipplji mmes from the digital branchcK. 

if^vannth. — In the metacarpo-phalangeal joint of the thumb motion is 
limited to flexion and extension, owing to t)ic width of the surfaces. In the four 
other fingers aljdnction and adduction, in n/hition to the middle finger as the 
axis, UTv al«i cjuitc free in the extended position. Flexion is the fn'cst movement, 
owing to the greater extent of the articular facet in front and to the forward 
obliijuity of the latcnd ligiimenl". Flexion to a right angle and extension to a 
little iK-yoiid a straighl line an- pennitliHl. Although ulxluctton and adduction 
may oi»>nr separately, flexion ami adduction aiul e.\t«-iiNion and abduction are 
a.-«sociatcd togi-thi'r. The movemenU in the iiiterpliiilangeiil joints are limitci) to 
flexion and extension. Fli-\ion i.-* the mort^ fn-e for llie .-ame rejL-«ni a» above 
pven, and in the proximal joint it exceeds a right angle ; in the distal joint it 
may be rather less. The greater freedom of the thumb is due to the motion 
in the curpo-metacarpal rather than in the lower joints. 




S40 



THE AMTWVLATIOXN, 



THE ARTICULATIONS OF THE PELVIS (Fipa. 2(57, 26B). 
The Articulations of the Pelvis with the Last Lombar Vertebra. 

Till' fit'tli Iiiinliiir \< in)it<-ii lo tlx' fir?*! Mtcnil vcrtcbni liv »i:rli jointti Six) 
li(^nu-iiLi ns itri- fuiitic) Ih-Iuccii the viTti'lim- iilxivo, with t)it- uililttinii iif two 
sjwciitl iii'Ot'-vioi'v lipuiKMil.'i 111! (■iicii .-iilo, as lolluws : Tin- liiiiitiir^<ici-iit lir/<rmful i» 
a strong, Imiiguliir liaiul, wiili iu nyit^x above and iiileriiiilK, when- it i^ iitiac-livd 
to tlie lower and front [lart nf ilie transverst- prowsM nf the lajHi lumliar veMdlnw, 
from which it radiates <!ownwanl and ontward lo th<^ ala of tlie sacnim and the 
Kdjareot i«rt of the i!iiim. ll hlcndrt with the anierior sacni-iliac li^anti'iil 
below and with the iliii*lniiil)iir li^pimput alwivp. Tht> ifin-himhui- firjameni alw 
is a stroHK Iriaiipidar hand, wliich passt's frmn the iqicx of the tninsvciTe pi-iicess 
of tilt' lilih hinihar vcrtehr.t oinwanl and «onit'wli!it hnckw;ini. ('X|witidiiiR to its 
attachment along tlie durwd two ineheni of tho inner lip of (he iliac crej^t. It 
represent" the thickened lower edjje of tin.' ventnd hivcr nf the liimhitr fsEcm 
CovtM'inp; the (jnndntriK liinihornni, and jrives origin to that iiiii^'Ie, It aUu hvlp6 
to eonipl<!t«^ the iliirnd honndarv nf the fal.ic [X'lviii. 

The Sacro-ooccygeal and Intereoccygeal Articalations. 

The 'taeriini i^ nniled to (tie eoecvx hv an oval iiilri-rrrlr/iriil iUkp, I>v »ii 
ftvfrriiir and a stmngftr fionteriov iiafro-<-(nr)if/rn! lii/frmnil, the <-ontiiiiiaiioN.t of ihe 
nnliTior and imsterior eomnion ]ip:an)eiitct of the verlehRe ; and hv lalera! lifftt- 
niriifi' ])a-HHin;;lHrtweeu (he eonina of the two Ijonei^, and between the transverse 
proeer^-.f!* ol" the first coccyf'eal vertebra and the lateral angles of the i^aeriina. 
The li^ments eoimectinj; the eornna of the two Ixinesare sometimes called inlfr- 
arllt^ular, as the conum ripiiiient articular priM-c^^scs ; but the ligament is i>rol»- 
ably the eimtin nation of the i>tipni!ipiuous ligament, winch roots over the lower 
end of the spinal eanal. 

The nerri-mpp!ii is dcrivod from the fourth and fifth sacral and eoecygeal nerves. 

The nevei-ul pieces of the etHvys an^ hehl ttiptlier hy the continuation of tho 
Rnterior and jMwterior lijranients deserilH-d almve. Small discji of libro-cartilage 
also couniHit ttieiu as long as they remain >4e|>arate houcti. 



The Sacroiliac Joint. 

TliiM IK a wynehondrojiis in which thi' cartilat;! -<'la(I itnriciihir snrfnec." of the 
xacnim and ilium are bound logetlier by a thin Ktratiun nf siifler tiliro-eariilii}^, 

wliieh may ennlain a synovial-like cavity. 

I n w>nie eases also intern^aentis fibrous tiastie 

partly binds the I'lirfaei'S together. e>|Krially 

near the dorfro-.'Upcrior boalcr, !>chinil and 

ab<jve which the churl fniri>ver»e fibres of 

/B^mH'v, R^v^^j^^— the dwp jkim of ilic ]>iisterior sacro-iliac 

/^^S^/ '^"^^iTi ligament -■•(•iin-times n-ceive the name of 

■■.■^?^T^ 'ritfy'^M^^". iKl'-nmn-Ditit lujament. 

"^'''}' ■'■■". -^^•''SSEfl ''''•" ""f'l'i'ir morti-iliae Ugnmenl confiistB 

'^i"« '^ "^ " ''•'" ''*>'•''" "^ fibres c<)Verin}; the front 
..-■^ -•" or |>eKie snrfaet- of the joint, between the 

~r^ pelvic brim and the great saero-sciatic notdi. 

The ptHi/n-ior txicro-Uiac liijnmenl is vvrj" 
Stronji- The (leeiter btindleii of fil>reit pUM 
inward and slijffilly downward fmro the 
rough area above and behind the auricular 
surface cf the ilium to the back of the lateral 
maw» of ihfl saenim. A mope dorsal or superfieiul band, i^onietime^ called the Imig 
or iihfUfu Mvro-iliae ligament, |)a»set< fnmi the back of the posterior stijierior iUac 




Fin. Wi— fMTn-IUnc Hnt. cat In * pUim 

ll (if Oir lupfjlur rtoll " 

r«l \tTii.-bi«. (Tnlau 



KtilM to ihM i>r Ihr luprrlur •mil Ihrvugh 
I ttttaad 



THE SACRO-ILIAC JOINT. 



241 



tpin« dowiinnrx) nn<I Hlifjhtly inwiinl to the l■lu^k of tlit- tlim] Hicnil vertphra. 
The cartiliijrr foitmrtiiijj (Ik- smriciiliir stirfiioc-* of ihU joint tear* nwuy, as one 
masH, fixHii fnii* or lln! ntlKT juirliu''' wlini tin.- imm-f an- fiirc'ihly !H^'{Kinit4-i|. Tltc 
ntTTt» supplying tl)v joint <'<>mc from (he ;<ii[>enor lUuU'iil and (.■xt<^riiiil bnin<')H'« 
of th« poatorior ttivioion* of the firsl and iwuiid ^<^ni] iK'rvi>. Thi^ Mioru-«cialic 
lipitn«ntfl aliio help to support thin joint. 

The ffreal or luiMeiior itacro-nei/itit- tiffamen/ is ttiin ami flat at ils nttarhed 
in<ii. narrower ami ihieker in th** centre, whirh thns liividw it into two triauKle«i,. 
of which (he broader is attached lo the po^iierior inferior iliac spine ami the i^ides* 
uf the wicnim and coccyx, and the narrower to the inner marf^iu of the ixchinl 
tuberoeitv, •tendins its /iilci/orm procfMt alon^ the inner margiii of the iscliial 
ramus, tin! free, Siarp edge i>i' thr falciforni process in continuoiin with the poate- 
lior bonlor of the liRaiiiciit and with the obtiu'ator fawia. Some fibres puss over 
the tuberosity into tJic tendon of (he hiceiH, of vrhieli thtf li>i:nnieni represents the 
proximal cimtinnntion. The direclion <it thi^ lij/nmrnt is fiX'm above liiwnward, 
outw'iinl, ami «lii;ht!y forward. It luwist-t in l>onii<liii|; the pelvic outlet ami the 

tit-rineimi ln(<*rally, and iM^lwei'ii it and thi- hip>hone is a hir);e i^pace subdivided 
ly [lie uMott or aida-ior nacrv-tciatic liffutnenl Uiui ihc i/rnil mcfti-vcudie /aramen 

pemmon •»<ito- 




Pia. :9eL— Aitlaiilmlon* of tlM> iitlttB.nairleir. iTaliil.i 

above and lh« mmlt Kfu-rn-xnolji- frn-mnfn Wlnw. This lijrnment lies in front of 
the preceding, and is triangular in form, it;« wide baw attached to the side of the 
Kicriini aiwl oocoyx, it^ aju-x to thft Lichinl Kiiini\ It* deep surface is e!o»iclv con- 
nertcti with the coccygeuH muscle, of which it n«pR-*cnt»t the fhiekenc<l «lieatli. 
Through the great saero-sciatic foramen pai« tlu* pyriforniii' niiii<cle, ami above ihv 
muwli- the jiluleal vessels and superior gluteal nerve, hi-low \\w muwic the winlic 
and internal piidic vewets and nerves, iho inferior gluteal nerv*;, and the iiervi-jt 
to the obturator inlcrnns and oiiadratua femoris niuscles. The small .tutrro-.^iaiic 
foramen is the smaller space Iwlow the small sciatic ligament. It ici bounded 
behiiHl by the gn-at sacm-scJatic li^^ment and in front by the aniootb cartilage- 
clad Rtirfuoi- bvtwc<M) the iiK'hiul s))itic and tulierosity, over which passes the obtu- 
rator inlerniw ntiiM-ht. The inlminl pudie vi'««eU and nerve ami (he nerve to 
thv obturator internum p«^ in through ihiit fommen. 




24S 



T-ff£ ARTICULATIONS. 



The Symphysis Pubis. 

The oiijwrsoti mcdiiiii Mirfitpfji of the jiiibic Iwnt'j- aw each covorctl with (i (hin 
layer of liv.-ilinc tiirliliif^r, nnilcil into a "-inglc intri-fiiihir r/iV bv ;in iiit<T|M>wcI 
luytT tif tibro-fJiriilnK"'. Tfw^ l«ttor i* bnimliT in fruni anil l>ol»w, iind biilp'* 
wiicfiully hcliind. (t. is nltnclnil to tlif Niirroiimling liK^'i'ii-nli' on uli situs', iimJ 
(ificii tviiitaiiiA a cWH. ThU cli-li nr nivity i» iwiuilly iiciircr th<- iipfter nn<l Iswk 

Crt, it doc.-t not n-ni'li the Kitrrnci:', nor is !(. lined liv nvnoviiil itm-diUiiuk-, ami il v* 
■j-or in tiie ffnialc, tlnHtgli ni>t gn-mly atli'('l4-d by |iri'jriiiiiicy, A (iliroii^ fijumle 
Hiirrtmnds iln- joini, wbidi U f'lirtluT ^iiv-iigitit-ni-d bv u-ndimum aliadntienti% The 
giiprrior and jiontirior iit/aminln ant biit slightly niarked traiiBverse fibres i^irengUi- 
ening the jMriosteiini. Thp finterior H^ani^iit is stronetr, «nd ronsisti of awp 
transvcrsi? fibres and superficial nbliqiu', dt'oussatinjf fibres connected witli the 
tendons of the iniiscles arising; fnim ihc body of ihe os pubis. The inferior or ntb- 
puhic Hrfttmriif h a thick triangiiliir maw of transverse and curved fibres, round- 
ing off the fiibpubtc iinfjh' <'f 'he pubic nimi, whivh formii the ventral aniilf of 
thv iic-lvii- outlet. 

Mtii'i-mi-iils, Mfrluiniiaii, r/c.— Owiufj to tin- thirUm'iwt of t.hv diw bctwpcn the 
fif>h linnliiir vcrlobm iind the siienim, iiiiivi'nK>ntJt»re more fnv herelhiin between 
any two lumhiir vertebra', and especially Itcxion and cxii-niiinn. whioli iwrnr 
in Mittin;^; or in rt.iing from the piltiiic positin*. The inelinntitui of tin* jH-lviit 
depend:* partly njMin the sacro- vertebral annte between the wirnim and iIk- spine, 
but aL-o, and in great [wrt, on the obli(|i]ity of the hip-lione> to the .laonim at ilii> 
satTo-iliiir joint. At the sacro-iliac joint there is no movement : it merely serves 
to brink shocks. In the erect position the base of the sacral wedge is direeled so 
largely for«-anl, and the ventral or broader surface of the sacrum is directed so 
largely tlownward, that tlio sa«;riim Is not held in ]>laee by virtue of its wedge 
slinpc, but is >iu*pcndfd from the ilia by the very strong )>iwterior wicro-iliac liga- 
ments in such a way that the greater the pi-essnre the tighter Is the union. The 
tendency to rotation of the sacrum, due to the weight of the spine transmitted to 
its forward projecting l«isc. is resisted above by the ilio-hinibar and below by the 
sicro-*fiiiti<; ligiiiiient» (the former directed backward, the latter forwanl from the 
wieriira). At iho pubic M-mpliysis then.' is only a slight ylehiing of the eartilupe, 
which may oei-ur at rhihlbinh, when ihe carlikge iis snflcr and mon- va^^rular ; 
but the deensMaliug tentlitioii.i fibres id' ihe nbdoniiii.il niuscles, which crons it in 
fmiit, would lend In brace the bones mon- tightly logetlier by their contnielion 
during labor. The siicro-eoeeygeal joint allow.* of flexion aii<l exien.-^ioTi. lu 
defecation and parturition the coccyx U pushed baekwaifl. Thi.s joint maybe 
ankylosed in adult life, but less ot^en in female.t than iu males, and its mobility 
eeems to increase during prt^nancy. 



THE ARTICULATIONS OF THE LOWER LIMB. 

1. The Hip-joint (Figs. 26P-271). 

In lhi« typioal tmlUaiid -socket joint the rminil head of the femur iti received 
into the ncetabulnm of the hi()-lK>ne. The enrtilage-olad snrlaee of the iiceiabulum 
i.» hnrsosh(ie-sh3|>ed, broader alnive and behind, and deficient below at the coty- 
loid notch and in Ihe depre.-v.iou at the bottom of the acetabulum, which is occu- 
]iied bv a mass of fat covei-ed bv svnovial mendirane — the so-called Kjrnoriat 
(Haversian) t/Utml. The artieuliir carlilnge of the head of the femur is thicker 
above, where it bears the weight of rhe body, and is wanting n little bi-biiHl and 
below the centre, at the depressiou fur the ligumenium t«rirs. The iicelabnlur 
rim i:* wnipleted 1h?1ow by the trauBverse and tlecusjating fibres of the iranmvrte 
ii(/'niii'ii(, which bridges over the cotyloid notch, and convertjf it intti a foramen 
Ibnmgii which articular vessels ii!i«s. This ligament blends with anil help* to 
supjwrt the coti/foid Vii/itmrnl, a thick filjnveartilagc, triangular on section, firmly 




THE HIP-JOJST. 



313 



fliuohe<t bv a hnnwl lia--*e to the rim i>t' llie ncctiiliiiliiin, wliioli it <leepen>i lo more 
tban a lieii)i>iila-n!. Iw ponaivo inner siirihre aod tliiii fret- niai^in lij^lilK era- 
brace the heiwl nt' ibe fumiir a lillle bevoijii iim (trealMl L-irciiiuferfiice nn<I, aiiled 
by awuo--[>liiTic pressure, hold ii in place when ilie capsule is divided. Jts Hbr«s 
pass obli()uelF from witbout inward, and iis outer convex surface is id contact j 
with the capsular ligament. It is coverc-d on both tides by Bvnovial mombrane. 
Tbe eapfuttir litfomaii ia one of tlte strongest in the body. .Snrroi Hiding iho 
j<Mnt, it is al(aeh<^Hl to the [>elvia at or near the rim of (he urctnhttlitm, oiKi'idp 
of the cvlvloiii lij;^.im«nt, and to the transverse lijruineiil. On the femur it is 
»tl;irhe>l ill front to the anterior iiitertrochanterio line, fruni tlic tnberi-Ie iibnvc to 
iho level <if llic lower part ot tlie small Iroehiiiiter bi'low. Fn>m die latter 
point itit li)ic of attiK-hmcnt pafnv* upward and buekwurd, iibovc the iiniiill 
InH-hanler, and llienco upward and outwaril on the posterior jiurfare nf the 
nt'ek, rine-hiilf to lwii-Uiinl« (if an inch inliTiiiil to tlw [HMteHor intertmi-han- 
tt^rie line or at iIh- jiiiictioTi of the niiddl<- and outer thirtU of the nt^-k. 
Sn|terioHy it Lt attnched at llie bm^c- of lim gn-jit iro4-lianter, intt-rnal to (he 







'■mr euaHiao 



mttlf «"0 VEIH 
TIHIHO Kia ICtVINO 
l.ie'dCHTUN Tcnis 



I ii< -i.v— Ulp-Jolni tacotondKCtlon. kTBatot) 

digital fossa. The innermost capsular fibres are reflected n|K>n the neck of the 
feniur toward the articiiliir marj^n, blending wiih the pcriosteuiii ami Itiniiiii^ 
three flat bands ur rdiHaciif", one behind mid one at either end of tJie anli-nor 
intertrochanterie line. The eitjisiile is Hiniewhnl loose, and its fibres run longitn- 
dinnlly with wiuue eiirtilar filnv-s iiiterwfiven. The eiretilar fihns ari' found most 
abundantly behind and below, whi-n- they form u bund arehinfj around the neck 
of the femur. The loiifriliidiiial libr<'> arc mneJi thickened in parttt by twwjvori/ 
ImmU, in<e|uinible from ihi- i'a[i:<iili', which {rreatly strengthen the joint. Many 
of thcM; Ixiiids are derived i'roiu the fii.'ieial sliejiths of the Mirniiindiiig mni^'Ies, 
which nn- — in front, the ilio-|)Mias, jwrlly .-^ipuraled fn>ni the eap.inle by a bnnha ; 
inleriuilly, the |>i-<rlineiis ; liclow itnd brhind, the obtnralor cxtemii.s ; bcliind, the 
obturator intemtitt with the two gcmelli and the pyrilbrtuii* ; alwve or externally. 



244 



TBB ARTICULATIONS. 



tW rpctiiK fi-mori* iiiul ttit- clittciis mitiimti^. 



The ubtumtor iiit«rni» acts likv a 



1 ttlf cHitcii 
jwwiTtiil stni|> lit till- liack m tin- joint. 

Of flu- tlini' (iritK-ijHil aociVMirv luiiicis, the ilio-fmi'irtif hiitui U lln- ^ir"ii{r''''t mid 
liiiu<t. ini[it)rt:tnC. SiijxTiorly it ih nttiu'hcil t<^ tlic iltimi, Ih-Iow iiik] Ix-liiml llio 
atitorior intftrinr sj>in« ; infrriorly it itpreiuls oitt tnaiigiiUirly to the autetior inter- 
troohanlerif lim* of llie fitiiiur. Iti* inner and ouK'r l)(>rders t'omi two verv sti-ong 
l>an<K between which tJie eapniile is thinner, so as sometimes to suggest (ne name 
of the inverted Y-ligament given it by Itijii'low. This liftanient is rarely torn, 
and forms the fnlonira for the maniiitdution in rediieing dislociitions of the ihigti. 
The outer or npper part of this band, [Ki-sing to the up|K>r end of the sinterior l>or- 
der of the pi'iiit trochanter, is sometimes <li'!>eri|jed as the Uio-tror!iiniUfir iiffamettl. 

The piibo-fnnoriil Imnd is the weakest, and [Kisses from an aren Iwtween tlie pec- 
tincnl cmineiiee find the cotyloid notch to the neck of the femur, above and tR'nind 
the inner hiind iif the ilio-femonil lijpimcnt. It is derived from the fiicein between 
till- peel incus iind the obturator esteniiis. The capt^nle )i^ thinnest lietween 
this and liir ilici-fc-iii<inil band, where It is ]>crforsted by an oiK-ning bi-twren (he 
svnoviiil (Mvitv and thi* Imrsa benenth the psims. The ixrhio-j'rniiir'it Itmul con- 
sists of slnnij: (Uiri-s iirixiiij,' fnini the ifx-hinni jn^t Ik'Iow the ucctabidiim, which 
curve iipwanl »inl oiiiwurd to the base of the greal trochanter interniil to the 
digi«il fossa, Whi'ii the lliij;h is flcxcii Ihcir direction i» nlnnutt straight from 
their ischial tn thfir fcmond altachnienl. Thi- rii|iside is weak doi-^ally below 
this banil. where it iHiially tears in disliM'utii>n. [{ctween this and the ilii>-temoral 
btmd snperiorly the capsnie is stniiig, and t^ fnrilier st rcngthcne<l by bands from 
the ^bitcn« minimus and from the h>fleetcd tendtin of tlie rectus, From the 
luttcr the («irfm«-(rw/tnjATic band passes to the nppr end of the vastos exteruUB 




Fte.3m.— Hip-Jolui.ftoM view. Ths cavlly I* dlilcnded artlflf Ullf. (TMttU.) 

Tlie litjnmi-nlKm trrrtt froiind Moment) ift not round, but a triangular, flat 
intcnirlieiilar Imiid attached by ils ajiex to the upper half of the denression on 
the head of the f<-mur, and by its l>ase to the transverse ligament and the margiiis 
of the cotyloid notch, the ischial [jortion In-ing the stronger. It is surrounded 



THE HIP-JOJXT. 



246 



1>T synovial m-nil>nitti'. uikI n-iircsciits a nii};rat«I portion of tlic pertinoiiK muscU. 
It it>»vevs n small hnuM-li of tin- ohiiirntor artcrj- to the licml oi' tlif fi-miir. It 
19 torn in dUlomtion of tW femur. 

Th* avHorial moHbriinf iint-s (lio iuncT surfacf of (hf <»)K^uk-, from wliioli it 
b rejected onto the ixfk of th« fc-niiir an fur ait tlic Hrticiilar mar^n, nnd onto 
Uie two free gurfnces of tlie cotyloid Ii)niiiH'tit, tliriKr liciiif; voiiliiiiKll lo tin- [wd 
of fat at the bottom of the a4;(!tal)uliiiii, aim] an u tiihiilur (.'ovcriiij; of the liga- 
mentum ten^. 

yerres. — ^The obturator, accessory- obiiiraior, anterior cniral, and grc*t ectativ 
or some other branch of the sat-ral iilexiifi supply the joint. 

Mowmentg. — All the movemeats of a ball-and-socket joint are permitted. 
The obliquity of the neck of the femur hIIows flexion and cxteottiou lo take 
pliire by n mtutioti of the heud without its eiirtiliigcK^'lud surface teavinju; the 
fiockel, thus j«c«ringi-trenplli for thew, the most itiipurtantniovcnit'iitH. Extension 
i« ltiiiit<^tl by the i^troiig itio-feiuoml band, \shich help^ to maintain the erect p^i^ition 
without mui^ciilar exertiop by preventing over-extenifiou in standing, for in this 
position titc centre of gruvity ikwendi; bl-hind ttiv centre of tlic joint and tends to 
nyjwrextcnd it. Flexion takea phice through ubont MO", until ehwkeil by (he 
coula*;! of the thig;ii anil nMornvn if the U»w i* flexed ; ottivrwim*, it in checked 




FlO. in.— HtHolni. rront Ttcv. The eaioiiliu 11eitm<nt hu bHD la:8«lr mnurtd. (TMIut.) 

Al about IMV by the hamniring mufeclcs. In all the other movemciitc th*- nrticulur 
portion of the head projects beyond the cotyloid rim on the i«ide opposite lo thai 
toward which the movement takes place. Abducttou t" limited by the pubo- 
femoral bum), adduction by the outer part of the ilio-femoral band niid the u|i|>cr 
Ijjirl of the eap«ulc. Rotation takes pliiec on ii vi-rtiwil iixi.< |ub>Hiiig from the 
K!id above to the lower extremity of tlie feniiir bi-low. T hiw axi!« in not coincident 
with (hat of the !>hun. Inwiinl nilaiioii i™ limited by the ischio- femoral hand, 
outwani n>tiitiou by the ilio-fennmd bitnil (ilr' inner [tart during exlcm-ion, its 
outer during flexion). The ligamentuni terei* is put on tlie stretch in flexion with 
alHluetion or oulwnni mtution, or both, but it is too weak to be of use 'm ret^isting 
tiic^f moveiiKrnlit or in tit rcngt bent iig the joint. 




246 



THE ARTICVLATJONS. 



¥ 



2. The Knee-joint (Figs. 272-275). 

This, the largest joint iii tlit- Ixuly, is ii nKxliHoi) liingv-joitit, » tiow bony articu- 
lar surfaces (tlief(iri<lylfsuti(l trot-lilrjir t-uriiici' uCllir tiiniir, \\w tuberosities of llie 
tjbiii and tlip witcllii) uri- not wt'll iuln|ilril tw ime iiiiollicr vxw|»t bv int'aiis of soft 
parts mid the iiitcrpuist.'d fibrf>-c«rti!iigi's. Tin; knee is vi-rv niiiH'rfi«iiil,ii»d is strong 
only byr<iLM>nof tilt' nunih<-ruiidsirt-ngth<it"tlii^ iij,iiini'iil.-<«n<lsurriiiiinliiintt-iidiin» 
and miiMos, wlucti, its well iia tiir widlli nf ih'- iumy surfiirc.-', n'.-iKl di^ leu-jit ion in 
(i|iitc of i\w Icvfnmc above and bdow it of the (ho loiigr-'l boiu-" in tin- limly. It 
n'pr«sc-nts two morpholojiically distinrt joints, (lie |ini(-lto-fviiionil and tht- tibio- 
ffmonil, thf latter also eomjMi^t-d of two latiTiilly jiinrtil joints, the median divininn 
bctwi'cu which is reproeiilfd bv tin* trriii-inl and imiic-oua li^itncntii. The synovial 
nicndmini' cif tlicjic joints has hlrndi-d into on«. '\'\\e jUtrim* e<ifiitule ot the knci' is 
Htn-iij;tlion<-ii in jiliiors by stnuii^ liiindp derivwl f'nim the snrronnding temloiiii, 
I'losfly ailhi'rciil to its outer surface, and known a:* the txifrtial (fujierlicial) net of 
ligaments. 

1. The intaital lale^-al tufament is a long, flat, strong hand which extends from 

the internal tuberosity of the femur, 
clnw to the ad<ltietor tna^nus ten- 
don (of wliieh it was originally a con- 
tinnution). to the iiiufr surface and 
inner honhr of the liliiii, on whii-h it 
dc«;eiids below the level of the tu- 
bercle. SniK'riiirly i( is hleniltnl on iU 
dwp snrfaei! with tin- fibroH-artilap; 
nn<i eapsuh', but is se [111111 led fmin 
tin- laltiT Ill-low, where it hriilfres 
ov*-r part of tin- srniimenihnimtsuj 
tenilon and the Inferinr internal ar^ 
ticniar vi-ssels. Su|ierfieially, it i« 
i>i>]>a rated hy a bursa fmni the ten- 
dons of llie KirtoHuH, gracilis, and 
ttemiteixUnosuH. 

2. The t-xternnf lalfrni tit/iim^ 
extendi downward and slightlv back- 
ward !is a rounded eord from the ex- 
ternal tuljcrosity of the femur to the 
middle oi' iW outer surface of the 
bead of tile fibiihi. Il en>s«-i^ over 
the iioplitt.'ns li-Mili'ii ami the vx- 
termil inferior arlienlar vessels, and 
i-t se[Ktntt(-d hy a bursa fntiii tlie 
biceps tendon, whieh split!* to ent- 
brace it. It is continuous Itelnw 
with the origin of the peroneus longiiM, of which it represents the detached 
femonil origin. A little behind this ligament is the broader but less eoiistant 
aufl less well defined x/ioc/ or pwlrrior vjimxal liiffral ligament. This exteitds 
from the externa) condyle of the femur, in eonneetion with the external gastroc- 
nemius tendon, to tlie styloid process of the fibula. It blends with, and ih really 
a iRirlinn of, the jmsteHor Uf^tnient. Both internal and external lateral ligaments 
are Htttiateil behind the centn- of llie joint. 

3. The pmirriii- Hf/ameiif pnijter is a strong flat biind winch ascends obliquely 
upward and outwanl as an exjuuiNion from the semi mem bninosiis tendon, from 
tlie back of the inner Inbenwity of the tibia, to the external eoiulyle of ihc femur, 
joining; the outer head of the gasti-.Mtiernius. Tlie rest of the so-i-;illed [toslcrior 
ligam<-nt nn<lcrlie$ this oblique portion, and is ihiit jiort of the eapsnie which occupies 
the interval- bet wccu the lateral ligaments behind. It i* a broad niemhraue com- 




aHTCHion eau- 

CIBL LICAMIHT 



'■TIHlon CMU- 
Cmi. LIMWEHT 



Fn. Sn.— Kncc'Jolni In io«lItiit ■cvtlon. ITerttll,) 



n 



THE KXEE-JOIXT. 



347 



pn«o(] of nonrly vortical bundlcit of fibiw:*, wtiich paiw from iho iip|K'r ninivini* of 
till- iiili-nxindvlar notch «nd of tlw^ arti<^iilar fturfnees of llit- fi-iiiitr In tlic dorsal 
mar^n of th« honct of ihi- li)>ta. 

4, The lit)amentttm patelUr is the ^itrong;. flat infrapatellar tendon of the tguadri- 
oeps extensor, extendinu from the apes and lower hordvr of the patella to the 
lower port of the tuhtTple of the tibia (where it dcstcends lower on tlte outer side). 
A in/nopial Aunwi separatrs the li^ment frotii the upper part of the tubercle, above 
which a ma«8 of fat M?)MiruteH it from (lie i^vnovial inenibranc. 

!*. The mpmilitr liyiimml \» rwn only in IIk* intervals iM'tween the above liga- 
ments. B«-hii)il it i» lliickcm-*! to form mowt of tbc |n»lerior ii)^mi.-nt. in fn«il it 
i* wanting bcnciitb Ihc ]uitf1l» iiiiil il» (vndoitH, lie(wt.'i-n whieh ui)d the tiit(-ntl 
liginnt-nts it i;> >ttri-n(;lbem-cl liv the fk-u-ta hitu iumI the ItitenU fibnm.i exjiansionA 
•if thi.- quxlrieeptt extensor tendon. These expannion-i, jtiis-iing down from the va^ti 
muevle», arc atlachrd to tlic sidtw of the |>ntdla ' and lb*- ligantentiim juiIcII.t, and 
to ihi: tibia iilong l\w obli<]m' Iin<-:< i-xlt'ii<ling from iho tnlierele (o the Iimut und 
(Miler lube nii^it !<;><. 'Hh-v reiirb as far Literally us the Intend lijpinifins. Exicrtinlly, 
ihe ilii>-liliial Imnd of ilm l:L-»fi;i lata, altarht-d to the external one uf the alwive itbliquft ■ 
linc!^, adds largely to the strength of the capsnle. The c»))»iile '\* therefore made 
up of two or three layen, and bclwveu the deeper layer, or Ihe capsular nicm- 



CKTCnil*!. LUTtllll 
tlBDO- 










until HuHiTiiiHa 

TtllBOIlB 



Pta. Xia^Kne(.Joilat, froM Tlmr. nnef ihenKnmvnutiavcitin ivm<n«dontb( rteiittld«- rTcMuI.! 



brane pniper, and the outer layers tJiere often exists a thin layer of fatty tissue. 
The ca^t'^nlar membrnne is utiached to the femur and tibia not far from their 
artioiilur mnrgims, :ind w adherent to the semilunar eartibges. 

(Jf thf S()-eHlbd inUmiif (ilecp) net of liffnwmU, mo^t may be well *ecn by 
ilividinglbe i|imilnirp!t tendon ^bove the }>»lella. euntiniitng the section Intendly 
and downwnni lo the lower eiiiU of Ijolh laterul ligiuiient*, and liirning down 
th>4 Hap thus made. 

(!. Sptoriaf lAijiunentx. — Fiiiin tin- synovial membrane lining the jtad of fat 
behind tlie lignmeiittjtn putcllH; two thin lateml fohI:> of niembniiie extend tipwani, 

' Fonning wbnt liiu been fdIIhI the tatend pattilar liffamailt. 



248 



THE ARTICCLATIONS. 



^ 



I m 



oiitt itii wirit Mi\t^ of till' jitiiolln, known as the alar liffamenU. From the middle 
of tin; wiiriia<;i' of the jwi! ii HitltiMli told, llie ligamtninm jnuea*um, extends tmck- 
ward mid tijuviiivi l<i the front of the iutereondvlar n<itcU. It ifpresents the 
n-nmiiis of the svnovial jMirtiiion between the two halves of the tibio-temoral joint 
and tM>tween the mtello-feinoriil and tibio-fcmoral jointe. 
On dividing tiie ligaiiieiiltim nincof^iim we M-e 

7. The finlt}-ior cruriaf HifiSinrnt, whioli t'Xli-»<U iijiwunl. iHickward, und otitn'unl 
from its lower attachment on the tnixT imif of the (Ii'|iix-ii>fioii Ui front of tlie epiiMi 
of the tibia, and between thi: fore t-iiib of the wmihiiiitr 4^arlilnge», to the donuii 
part of the inner surfuct- of the outer eoiiilvh- itf th^- fi-iiinr. 

8. The poHtrrior i-rui-itil fit/nim-nt is stroiiycr, ^liorlir. mid mow verlieul lluin 
the miterior. Fnmi bt-Iiind lite tibinl spine, fniiii tlie poplitoil Dutch, ani] 
receiviiiK fibre* fniiii ihr [HwU-rior eorim of the I'Xtiniiil wniiuimir cartilag*', ili« 
fibrcif iuMvn<I wlifrhtly fiirwiinl nod inwai-d to the front of the outer side of the 
internal condyh- of the femur. H<-hin<l and below it is adherent to the jtosicrior 
ligament. Itor(HSi-i< the miterior crneinl iignment on its inner side, and is blended 
With it hehiw, bnt sepamled from it aliove by a V-et>aped space. The synovial 
membrane is prolonged over them both. 

The external and internal wmitumtr fihri>^nrHhtijr» arv two erescentie jilates, 

of a dense, eonipiiet sinictwre, ntlached by 
their thiok, ivnvex, oiiti-r t^iirfiiec« to the 
iiifide of the eiip*iile. They rest U}K>n the 
circunifi-rentinl porlioiM of tht- tip|HT iirtic- 
lllar fnei-I.H of ilie tibin, eovcHiig a little 
les-i timn t«o-lhirtIrt of these siirfaws. They 
itirrea^o the eimeavity of these snrfnire:* for 
urtieulation with the feniTir by a gnidnal 
thinning to their eoncsive, free inner Iwrders. 
Their iim»er, concave, femoral, and lower 
flnltened tibial surfaces are free and eovered 
by synovial inenibrane, Thev ta|«;r to their 
atliii-hcd cndw or coniua. which, are pnrely 
fibriHi*:, and arc fastened in fnmt of and 
Ix-hind the til>iid t'pine, the comua of the 
«xleni.tl ctnrlilage being within those of the 
interniil. Thv extermil semilunar cnrtiliiKC 
is therefore mon- eirr uhir, (he internal is 
mort! oval and hmgiT fnmi licforc biK-kwani. 
The external is also more movable, from the eloseapprnxiniution of its corona 
and fnmi ihe ^rwiter laxity of the part of the eapsiife to which it is ailaehed. Its 
outer fturtiice i^ grwvcd Ixrhiml, and separated trom the capsule by the |ioplitcns 
tendon, the bursa Mirrounding which coiinects with the joint above and below the 
cartilage. I 

The Intnavej'ne Uf/amftil is a variable transverBe hand which connects tlic witcr 
snrfiicos of the two semilunar nirtibigcK in front, 

Corou(iri) lifftwifnt is a n:Hiic upplie<I to that part of the capule between it« 
aftaelimcnt l<i the semilunar rartiliige* above and the head of the tibia Wow, 
which holds the cartilages in up|MKitiii[i wilh the tibiu. 

The Kijnmiinl membranf, the liirj^-xt in the bwly, lines the capsule of the joint. 
Above the imtclla, in front of the fnniir nod beneath the extensor tendon, it 
forms a hirgr jKnich. conimunieating in imwi v:\n-* with a hurm above it. The 
latter lies between ihe extenwr (endon and the front Mirfiioe of the femur, above 
the attachment of the capsular membrane, Traei-d downward, the synovial mem- 
brane is found to line the capsule until it mt^ts the .«(tmilimar eartiJap-s. where it 
is reflected onto [heir upjHT surfaces, around their free inner margins, onto their 
lower aurfaceii, and m\ Imck to the jtortion of the capsule eallnl ihe coronary liga- 
ment, which \t lines down to its tibial attachment. From the cajwule behind and 




Tm. 7H.~t\\<e Kumllunai cvdllaigai of tk« 
rtgbl km-t-Jolot. (TMlut.i 



I 



THE KNEK-JOIST. 



249 



'(wmiturair wirtilftirf;' Vwtow tliis nu-m1>raiK' is reflected onto tlie cnicinl li^- 
Pl», u'ltich il ii)v<-AtA, exi^^pt Ix-hiiid and betow, and tliui^ •ihiits ;liciu out of ihe 
HViiovinl r:avitT. Il aliio fornix the alar and niiivous li^^tiicritK. Sffiufvinl bursas 
bt'noatli and belween the gasirocncmiua and irotuimuiiibnimtsii; iiiU-rnall}', nti<l 
beuf^lb the popliteus tendon eKtemally, may oonni.'ct willi llu- i-ynoviiil «»vity. 

The nerrv-supptfi comes from the iiiieniid and vxlvriiul iwjplitcal, lh>' anterior 
crural, ami tlie obttimtor nerves. 

j/orcjumto. — The principal movement!; arc th*"** nC flt'xii>ii iiiid ixli-nsion, 
which result from a combination of pUdinj* nnd liingv-movciiii-iit. This diM-s not 
tukc place on a fixed axis, but on on*- whioh shifts with llu' pointTi of ciinlaol fi-om 
iK-hint) forward in extension, and ri'rr wvwi in flt-iion. Tho piiints of contact of 
the nrljciihir siirfaooff arc wtnetftnlly cliunf^iiip iVom the flattpmnl lower surface of 
ilic fomomi c"ndyh-» in i-xtension to tlioir nion- shnrjilr eunvd dorsal surfaces in 
flexion, and from the fori- (>art of iht- tibial snrliiwa m extension to their hind 
pnrt in flexion. Tin- hiiwcni^-* of atlnchnient of the semilnntir cartilapes allows 
them to adapt themfwlves to the diflerently curved surfaces of the femur. 

A« lh« Knw itt moved from the flexed to the extended position the crucial 
ligamoi>l« hc^onie tcn.st^, and keep pulling luick 
the nniinilar ><urfaoe of the tibia, so that the 
poiniK of («ntart of both tibia and femur are 
shifted forwanl. This relaxes the lijmmcnli- 
and alloii-s iIk' motion to continue. The ante- 
rior crucial ligament also rejfists the tendency 
of the extensor muscle to dt»plHC>e the tilita 
forward in extenifion. In flexion the cnxinl 
ligaments caufv n ifhiAing of the points of con- 
tact in till* oppiwite <iireclion, ana th*- |HB>terior 
crucial ligariK'nt prevents the tibia from being 
puth-tl Imckwanl by the flexor nuisclcs, 

At the eiul of oxlensi'iii th<Te in a !«lighl 
outward rotation of the tibia and foot on n ver- 
tical axiii, and at the enmmi'neeinent of flexion 
a stisht rotation in the opjiosite dirf-eiion. 
This IS due in |>art to the greater length of tli- 
inner condyle, onto the outwardly directed fon 
part I'f who^e articular surface the inner facet 
of tlic tibia glides forwanl in outwanl mtalion 
nt l)io end of extension, and Ixu^rkward in in- 
ward roUiiion at tin* begtuning of flexion. Ex- 
tension Is checked by tho lateral and }x»'terior 
^eamenu and the anterior crnrial ligament. 
Flexion is cheeked liy eonlael of llic *oft parts 
at about l-'i.i". In extn-me tli^xion the liga- 
mentum patelbe, the fore pnrt of the capsule, 
and the posterior crucial ligament:* arv tiglit* 
cncd. The relaxation of the ligaments in the 
juirtly flexed position allows an inward and out- 
ward mtation. on a vertical axis, in which the 
semilnnar i-nrtilagc:<: slide back and forlii on the tibia. This rotation is im(K).4ttibIc 
in the ext<-iided position owing to the tension of the ligaments. Rotation inward 
is ebei-kfd by Uie anterior crucial ligament, rotation outward by the lateral liga- 
ments. The ereet position, in winch the line of gravity descewls in front of the 
knee and tends to hyperextend it, is maintained, in great roeiuturc, without mu." 
ciilar eflort by the rei<i»lan(-e offerwl to over-ex ten. -ion bv most of the ligimii-nt.-. 

The nioveinenis bet.wtn-n the )iiitella and ilie femur an- a com bin.-i lion of sliding 
and coaptation. In moving fnmi the extende<l to the ilcxetl jiosilion the lower, 
middle, and upjier parts of iJie |iutellar facets are suoce-ssively in contact with the 




Fki, 27rv.— Kuix-j>.'iii^ oiiU'f tide. Til* 
■yn-iiJul Ma tn knltlmllv diiirniliid. 



250 



THE ARTICULATIONS. 



iipppr, middle, mid lower parts of tht- truchlcar Rurl'ace of thr feintir. In extreme 
flexion a narrow vertipul "-iirfiicf uii llu- iiim-r i«idc wf tlic jiutellar fawt is in eoit- 
tiicl willi the fore |virt of \\w oiiti-rlionli-r of llic imiiT timdyli' of llie fctniir, the 
imtellu bciiifi liinied nion? oiitvvani I>J' tlio cxtt-riiul cu>ndyU>, A}ptiti-->I wiiich il.-t 
ii|i(wr und outer jmrl renXn. 



.'!. The Tibio-fibular UoioiL 

Th« ti Ilia and fibula svrc united at their tip|)er and lower vnds by juinl>i, and 
between tbeni by iin intrros^eoiis membrane. 

A. The SaperioT Tibiofibular ArticuUUon. — In this joint tbc oval, fluttcntHl, 
iiblic|iii' artri'uliir siirfiK-)- on tbe lifiid of tlie filmln i* eoiiiici'tod wilb lluit on tin- 
cNli'niiil liilKTiwilv of tli<' liliiiL bv ti iiifuiiilnr Cymnnif, stri'iif^tbcMcd in front and 
U'liiiid by fihrfu whifb (la.-w downwani mid outwartl fnini tlw tibia to the libnla — 
tin- anterior an<l poKl/rlor tcaprHor tiliiit-fifmtar tit/nm^it*. 'V\w eApHul<! Ik nnt 
infreipH-ntly imiH-rfiH-t above and iM'liind, when? tbe synovial cjivity of this ji«nt 
may eommnnieate wiih that of the knee ihrongh the medium of the bursa beneath 
the ]>opliteu»i tendon. 

U. The Interosseous Membrane extends between the outer border of the tibia 
and the interof^eous border of the fibula as a firm aponeurotie membrane, whose 
fibn'S deseend ij>r tbe nioift piirt from the tibia to the libulii, with a few in the 
opposite direction. It i?^ sepnnited fnmi the Mifierior tibio-fibiiUir joint by an 
oval o}X'iiinir ihrongh wlnt^i ihi' iitilei'lor tibial vtwK'U piiKs, iiiid below it is eon- 
timioiiK with the inferior iiiieix»-M-iMiH lipinieiit, belii^ pi-Hbnited by the anterior 
pt^^ruiiHil vu^-U. It serves mainly for mn.-x-iilar ntlitcbnieiit. 







IMTtKSMCOU 



Fki. 7».'-TiIi<<Haraal and calrjuwo-ulragoluid ■nltulalloiia. Id corona) ainlan. The lynovial aaca a>« 
oMcodvd. (T«iut.) 

C. The Inferior Tibio-SbnUr Articulation (Fig. 276). — The mtiph triangular 
fiurtkees on both bones, fornietl by tin- iiifiircHlion of their interosseijus borders, 
arc firmly imitetl by the sh<irt, utrotif;. obli<|iiely tninsverw fibnw of the in/crior 
intero»iWM"i fifffimint, to within » ipiiirter <if an inch of the iaret,-> for the iuttr»iniluit, 
wlierv two narrow nrtieidtir fiin>ls, <-<)iitiTiiion.« \tith tlioite for the aKtra^Iu,'', urit 
ia contact. The union in Ktrongthnnod in fnmt and liehind by the anfft-i'or and 




THE AXKI.t:^OIXT. 



361 



poM^rior inferior Uhio-fihuinr Hf/ninfittK, Hal bniiil!« wliii'h exierwl nornw tin* yiiat 
imin rile lowor cml ot ilic tibia oblitjiiolv imtivjinl and downwari] to iln- lw«tT 
end iif tlic fibuta. 

Tho frammTte Ugammi it) a thick, strong band, below the posterior liga- 
mrnl, wbicli exIeDtls from tbe posterior Imnler of the lower anioiilar siirtaee 
of (lie tibia oiiivrard, downuiinl, and a little forward to the inner snrtaee of tlie 
«-xu*niul mnlkiiliis, in and almve tbe fossa. The nynorial membriinr. (^vutiniHins 
wirh (bnt of tbe ankk-, extend* i)|i between tbe bones in front and behind as for 
as th<? inferior interww^^'ous lifiameiil. 

Tl»e mnrftamtm m the**- joints Miiifitxt in u elifiht yielding or vertical pliding, 
wbieb i.s alhm-ed by tlic ohliiinily of tbe lif^menltf. Tbe upward eliding of the 
fibniu i* u«roni|>»nic<l by a »li{!:ht widi'iiinj; of the tibio-libiiliir niortiee. which 
occurs in flexion of tb« nnkle. Tbe inferior intero«ieoii.4 ligHoient i« put to a 
gn-At Himin in tbe injuries pnxliieing " I'oit'n fracture." 




Flo. m.— TIMo-UTul «tileu1«iI<iD. wiwr Mdc. The rarltT '• ■rtMld«lli rti»t«i(l*il (T«tut.) 



•1. The Ankle-joint (Hkb. 277,278). 

The ankle \» a hinge-joint, in whieh the artieubir Knrfuec:^ of the lower end 
and internal malleolus of tlur tibiu iitiil of tbe external niiiUeobix of tbe (ibida 
form a mortice, into wbitli llu- ii[i(nr :iiid lati^ml fae^t-* of tbe a.stnijpihis fit as a 
tenon. The transvente lif^timent lie^w to complete tbe tibio-fibnlarwieket behind. 



252 



THE ARTJCVLATIOyS. 



Tlie eaptidf, etrfn^tlieucd and prot«ct^ liy the strong tendoofi passing over it 
diviilc'd, tor dtriicriptiiiii, iiitu tlif I'olluu'iit;; ligiimunts : 

Thf inlrrnni laUi-iil i.>r tlcttolil ti'jiiM'-i\l k u litnjiig, flat, triaiiptilar band wliich 
niiliatos fnun tlio lower and vcntnil burdcDfof tlie intiTtial malkuliis downward nnd 
baokwnnl Id tlic roiijjli iiinori»iirriu'<'<if t do nstnifpilti!*, downward lo the su^tcntacu- 
liiiii tjili of the Of (iildf, and downward and forward to the neaphoid and the 
margin of the inforior (!alcaneo-^'aj>hoid li^nK-at. A xo-ralled depp portion 
(le^citnd.-i tVoia tlie nnlcli on the lower imrd^r of the malleolus to the depression on 
the inner surface of the astragalus. 

The cxicimil lateral liffiiment prcHenbt three fteparate diverging hands : 1. The 
aiit'Tior /aMi-it'ubw, i^hort and rihiwn-liki-, niwaii'S from the ventral border of the 
external malWIus obliquely forwanl to tlie a-ttntpdiiji, in front of its external 
lateral fai-et, 2. The mitliUf /iiitririiliiii, >irong and n>iind, (ic-wend* Kliehlly 
backward from the tin and iJie fore ]iart of tin* outer suriiice of the eJttoriial 
malleolus to the middle of the outer stirtaci' of the os oaleis. .'1. The poMerhr 
j'aacicuJus is the slrongt-Ht, and panHes from the dorsal Ivorder and the foAMa on 
the inner side of the external malleolus almost horizontally inwanl to the outer 
surface of the astragalus, behind the faeel, and to its external tubercle. 

The anterior ligament ia a thin, loose membrane in front of the joint between 
the hkteral li);aments. It is attached above to the ventral mai^in of tl)e lower 
end of the tibia, above a slight Iran-iversc groove, and below to the rouph upjier 
axiHrt of the head of the astnigidus. A mass of fat bi'neath it nuts in the 
groovf of tlie neek of the astragidiis. 

The ponterior llffiimmt is very tlun and weak, and <•lln^fi)'tl< tif sc;itten'd ol>liciue 
tibrtw between the dunwl margini<^ of tiie artioular wirfaee* of the tibia and the 
!iiftnigalu». The flexor longiis hatlueii< tendon iierves Uirgely as a posterior 
ligament. 

The »i/novinl memlirane i,-* very loow on the anterior and posterior ligaments, 
forming lolds between the tibia iind ihi- iistnignlns. It forms a short ml-tlr-Mir 
between the tibia and fibula, in addition to lining the tigamenttt of the ankle. 

yerre«. — Brikneheit from the anterior and posterior tibial and the internal 
Aaphenou.4 i^upply the Joint. 

The mnt'CMtntb of the ankle are flexion and extension through a range of lew 
than SO". Flexion or dorwil flexion, in which the dorsum of ihe foot and toes 
appniaehes the leg, is limited bv the posterior ligsiment, the posterior parts of the 
lateral ligaments, and by the contact of the ventnd margin of the lower end of 
the tibia with the neck of the astnigalns. In extn-nie flexion the libtila >>• slightly 
raiiied and eprea<l Momewlmt from the tibia, to aecomminlate the wide fore ]«irt of 
the upperarticular.Hiirfaieoflhf astragalus. Extension or plantar flexion, in which 
the toes are brought nearly into line with the leg, is limited by bony contact 
behind and by Ihe ten.iion of the anterior ligament and the anterior parts of the 
Intend ligament*. Extreme e.xtension is accompanied by some adiinclion and 
slight supination of the fool, which prolwibly ix-curs in the tiirsjd joints ; for, 
although in tliis jKisition the narrow dorsal part of the as! rsigiilu;^ iiieet is lesf 
tightly held in the wide fore part of the tibio-fihular mortice, yet prolMibly no 
lateral motion nornmlly occurs except from external force. In the en-cI piwlnrc 
ihe line of grnviiy falls a little in front of the axi* of the ankle, wliicb ii» oirected 
from within outward and baekward.and therefore tendji to flex il. Owing to the 
ubll([ne axis of the ankle the leg in<ives forwaril an<l outward in flexion of the 
joint, but lhi,« oiitwanl movenu-nl of lln- U-ipt cannot <«'enr in the ereet position, in 
which the legi are nearly [winilh-l and ciiiiuot diverge from one another. Hence 
flexion !■> limited and the ubiiiiuily of lite axi.H helps to secure stability in the 
erect nttiinde, which is oihiTWiT.e dejiendent iin muscular action. The lateral 
ligaments are ofken jiartly ruptun^d in sprains of the ankle and in "Pott's 
fraelure." 




.^.- J 



THE TARSAL JOISTS. 



263 



5. The Tarsal Jointo (Fig*. 276-279). 

Tbe Artlcnlatlons of the Astragalus cmi^Ut of (1) ii pitetfrior and ertemal 
aMragato-<ali-ii 11 i.ul joint, uiiil (^) ao atttfri'ir dihI mU-rmif ralea»fo-aMt<ti/ulo- 
aoafi/ioid johit, lh« fore [lari of uliich, or the anlni^lu-M^ipliou) |»>rtiun, U jnirtly 
supported and enca[Muilatie(i by the two caluaiivo-^ctiplioid Ii(^iniditi( iinitiui; tli« 
OS mlcia and (h« iica|)hnid bone. 

(I) In the ftoMeriiir ai4rnffat(fealfaHmf joint tho (Ujrwil [wir of fsiwt* brtweei 
these Iwo bon«s are held together by a ntjHoi/r, .'•|ilil ii|) into ru-vcnil ili^^tinot flips! 
as fnlloiT* : An internal tiMraffalo-tvilcouttil liawl |mi.vuts from the inlorn.il liiliirrlo 
of the astra^hlr^, on the inner side of the ijronve for llie flexor Irmfru^t hn)in<:i» 
tPndfHi downward and forward to ilie back of ihe suMentn«tdnni (iili. The txitdfrwr 
ai^rtigii/o-ealcanral lignmcnf^ attached above to (he externsi liibetr^le of the astra- 
galus, Hprcads out onto the adjacent upper and inner surfaee-' of the os eiil<'i». 
An rjirritid Hf/ttmml connccti; tJic two bone« henenih and in front of (he middle 
slip of th<- cxtvmAl latoml ligiinient of tho ankie, wiih which it§ fibres are 
{andk'l. The jn/rrowewtw Hgfimeitl U a Klrong band of lihre8 pas.-^ing vertii.'ally 
h".-twwn the cnK>ve« of (he lutni^lu^ nnd oi' cak-is, which together form the 
MitrM pftiU. Il ^piinit«>K the two »rlii-iiliiti<>n>f l>ctwern tiK- nstniealu!< and tite on 
mleiiK, and Pon>fi»t» of imperfectly sepiimie laven', one of wliifh serves as tho 
anterior ligwnent of the jHnitvrior joint, nnd the other m xUv posterior ligitment 











Vta. m;— MnUu-lanal Joint. Hc^Hcd Rum above, (lie utn^Iiu hflilnc bma nmavti. CTsRtL.) 

of the anterior joint. Fiirtherraope, those parts of the liitcnil tigamcnts of the 
nnkle wliieli reach ihe o^ calcia help to unite it with the a>^lmpilii». 

(2) The ca/<^ueo^i»trar/tilo-tcaphoid juinl is between the jinlerinr fawt on the 
upper Hnrface of the o^ calcis and the fueets on tlx- lower Mirfiiee of lli<' lieml and 
neek of the aKttagalus, and lictween the h<'^ii) of the ii»(mpihiK tind ilie M-jiplioid. 
The bones are hehl logethor by the following lignmenli', in nildiiion (■> the intenK<- 
seous ligament, whieli limits the joint jMSk-rtM-xternnlly. 

Oalcuso-Kaplliold Ligaments. — The in/frlnr or intminl liytmifnt is bnia<l, llnek, 
and (Hirtly tibro-eartilaginou». It llrmly iiniti7< the fnnit nnd inner et^lgt-H of the 
stistentneninm tnli with the inferior ^orJiui^ of the ^euphoid and iip> inner -^nrfaee 
behind the tubercle. The upiwr siirfiiee of the ligament ia itmooth and articular, 
and oom]iIcIei' the mwket for the heiid of (he a.'ttragalii.i below and ioteroiilly. The 
upper pari of il.i under ■«uriui>' prewiit.H « smooth facet for the tendon of the 
tiliiuli* piHierior, wliieh aids in wnmiorTiii^' the head of the aslt^galns. It is 
blended interually with the internal luteral ligstmenl of the unkic, and externally 
and above with iIh; rxteittaf or auperior ealvaneo-«eap/toid Ugamvni. The strong 



^ftand abc 



254 



THE AUTJCULATIOXfi. 



fibn?3 of the latter liganicnl paiw obliquely forward and inward from the loi* jiart 
of the upper Biirface i»f the 03 ralcis, externa) to its anterior iipiier facet, Ut ihi- 
outer surface of the Hcaphoid. It limits ItolJi the anterior astragalo-oalcam-jil and 
the a."t niga I o- scaphoid joints externally. The t^peiile of the astragul()-wjipliitid 
joint is completed sii|>eriorl_v hy the atdraf/nlo-nfaphcid figamentf a broad, ihin, 
mcmbmnotis band, wtiieh eonvci^i^ from the iippiT suriaec of the head of the 
astni^ilii); to the upper ^tirface of the sciiphold. 

The gyvovitil mrmhrnnr of the posterior ostrjipaloHadrjincjil and that of (he 
cslcaiieo-astrupnlivMcaphoid joints are di»-tiiiet, iind wparatcd fr')m one another hy 
th*- inlernt..i.oii* lifriinirnt. 

The Calcaneocuboid Articulation, bclw<^pn the contigiiond facet* of tJ)p os calcis 
mid liie ciiiwid, form*, with that hftwci'Ti tin- aslnijiiiliis and waphoiil, tlw mtdio- 
UirKiil, trnn*vfiiw liir«fi/, or Choparf'i-johif. Tlie siirfncx-s art? iiilil liijji-lhcr bv the 
follrtwitig ligaments' : The inferior cahnni'ii-i'ufioiil !Uf<tmntf» con:«ist of two jHirtiniM, 
known tin iilniilnr liijitinmln. The nniH-rficial pari, or hvfl /itmilitr lif/finirnt,an*f» 
from ihi! under ^turfaci' of the os i-idei* bclwieii tht- po^li-rior and anterior tnbereltt*, 
and exiend* fi)rwanl to the ohrKiiii- rid(;i' on the nmler jiurfaee of iheciiltoid. From 
thin ridp- wiiiii- fdircs eontinne lorwanl, bridginj: over ami eonveriin^ into a canal 
the gr<Mive for the jx-roni-n.-i lnngii-< tendon, and are attached to the bases of the outer 
four mefalarital hones. Tliedti'p jjoriion,or«Aor/^/an(oi- //^ttmoi/, attached to the 
under surface of the os caleis, to and in fnmt of the anterior tubercle, extends for- 
wnnl and inward to the depression on the tinder surface of the cuboid behind the 
ol)Iiiiue ridge. The mprrior etileaneo-citboiil liffament connects the adjacent parts 
of the upper surfat^'s of the two JKines, blendinj; externally with the outer part of 
the short plantar ligament, and internally with the intcnuil or inter onaeoUH calcftiieo- 
euboid lit/a)iic»i. This stronp band connects the inner surfaces of the two Iwnes 
near their articular margins, lying deeply in the hollow Iictwccn the i* caleis and 
astmgahis, where it is closely oonnectol with the exlenial cailoumu^eaphoid 
ligament. 

The ifi/noi'iH/ membrane is separate from that of the other tunsal joints. 

Mocemrnti'. — The movcmeiitN of the fore part of the foot on the hinil part 
take place at the medio-tarsal j<'int. The nn>venients ut the adeimeo-tistntgaioid 
joi»(» are inversion ami ever!'i<m {tnrninf; of the solo inward and outward 
re.spectivi'lv), and ndduetinn and alidiietion (the movement of the front of the 
foot Ut ana from the median line r<-s{H'etively). Kotii of theHc formn of move- 
ment owur also in the medio-tursai joint, and besides them there is here rpiiti^ 
free flexion and extenHion around an <ihli(]ue axis, extending from within outward 
and somewhat backward and downward. Flexion in •^mnlianeous with extension 
at the ankle, and extenwion, which is more limittxl, is simultaneous with tiexion 
at the ankle. Thus, the variety and range of motion of the foot are increased 
beyoiid the limtletl Hexlon and extetision allowed in the ankle. The a«tmgillo- 
scaphoid joint is of the hall-and-«M.'kct variety, but, owing to the connection of 
the scaphoid and culioid bones, its motions are restricted bv the eoneavo-coiivex 
cateaneo-eiihoid joint. In the medio-tarsal joint adduction and inversion are 
cnmbine«l with Hexion of the foot and abduction, and eversion with extension of 
the foot, the latter motion being limited by the plantar ligaments. The culcaui-o- 
iwaphoid ligaments also limit motion here. .Vt the mcdio-lursil and astnigiilo- 
itileaneal joint.-i increase of the arch, eonibined with adduction and inversion, or 
dci-r^'Jisc of the areh with abduelion and even-ion, may oecur, leaiiiiig n's]R'etivcly 
to chill- or flut-fuot, when for any reitsun thesu positions are exagjreralwl and 
jM'rniaiient. 

In the Oubo-scaphold Joint the niboid and scaphoid are nnited by — I I) a tlor»ol 
Hffameul, passing obliijueiv fnrward and outward rmiii the Muiplioid to iht? cuboid ; 
(2) a plantar lit/amenl, sinnhirly disposed on the plantar .iiirfnee ; and (3) a ittrong 
iiilei-OMt'O'Uii (if/(niuiit, eonncciing their ooiilignous Kurfneeji. whieh, where they touch, 
present small articular facets, whaiM; connecting ligamentii are lined by an exten- 
aoD of the scapho-cuneiforra gifnwial mciitbmiie. 



n 



THE TARSO-META TARSAL JO/XTS. 



S5S 



: 



• 



The Scapbo-cimeiibnD ArticnUtion. — The cra|il]<H<l is unitptl in one continuoua 
joint to tin- three oimeitorm honeys tit front of it hy (1) Nti^ng (hrml fi(fament» 
fr<)m the uiipvT Mirfiioe of ihe MTi|ihi>i(l to th»t of wich of the three etineiform 
liotie:* ; ami i>_v (2) jJunlnr riifitiitrnU siiniliirly 4lii<|iii!K'(l iK'iic^ith Jind eontiiiiioii^ with 
thi* fihrcjt of \\w, tibialis iiosierior tentlmi. The hittiT teiuloii, iiy [xi)>»inG: outward 
■» well n>t fi>rfvsn1, Mn^nj^thens lh« [r»n.«verst- nreli of tti<^ foot. The uor»il and 
t^antiir ligaiiieDtt an; i>ontiiiiio)in on the inner a-HpeoL of the itiienial cuneiform 
bone. 

Tbe Cnbo-ctuteiform AnicnUtion. — Trannvcritc fibrei^ iinito the donial, plnntnr, 
and conti^uow anrfaoca of t)ie ciihoid :in«l external ouueiforni bones, forming th« 
ttoTMit, piaMinr, kikI intrronteotts liganxfuU. 

Intercttneiform Articolatioiu. — ^Tbe three cuni>iform bones are similarly eonnected 
by transvers* tior^tl and i^troiig inlrroenfoiiJi hgamrnt*. On iht- jilantar surface 
there is a strong band passing; outward and forward from the inner to t)ie middle 
cuueiforni Iwne, but the fibudiii poKtcflor trndon takes tlw ]dac« of the other plantar 
ligaments. 

Stpmehf Mrtnbratif. — \ single synovial cavity is common to the s«iplio-cimei- 
formand tlic intercuneiform joints, and m^nully tu the cuho-euiieiform joint, t hunch 
the latter may liiivc a se|)anitc synovial cavity. Tlie synovial cavity iK-twei-n tlic 
cuneiform bonv ii.»iiuliy extends fi>r\\7inl between the internal and mid<IIe enuei- 
forni, to iK-ci^mie i-ontinticniK with that of the larwi-meliilarwiil jouit* betwceu the 
middle and exti-riml eaiii-ifunii-i nnd tho H(-ci>ntI »ii<l thinl nic-liiiiir^il^. 

Tiie tnnrrinrntK in the above archrodiiil j"inlw, Ix-lwei-n the tai-Mii bune* in front 
of the nieiiio-iarsa! joint, are limited to a ^li^fjit gliding, due lo itw weight of the 
body ratlier than to mu.'wular antion, whereby the transverse an-h of the fool la 
either flattened or deepened, thus increasing tlie elasticity and plianey of the tan^iLt. 

6. Torso-metatarsal and Intermetatarsal Articalatioiui. 

Tarso-metatarsal Articulations. — The front siii'faces of the ihn>e <uneiforn» boues 
and of the cuboid articiilate with the proximal facets of the five metatarsal hones 
along a line (Ilcy's line) made irregular by the forwani projection of the internal 
and extertial cuneiform bones. The first, second, and third nulaiarsids articulate 
with the iriternul, middle, and external cuneiform bones res |k'c lively, the fourth 
and fifth with tliei-iiboid. Thesecon<l metatarsal is weilgi-d in between tlic iuternal 
nnd external <niu-irorins and iirlicnhilcs with them lalcnilly aixl with the middle 
cuneiform proximully. In addition, tlio fourth metatarsal hone iisnully arlieuiatei! 
with the external eiineiform httenilly. Tin- wirtaee* are held together by dorod, 
plantar, and inter-wMCOiis ligiiments. The tloma/ l!i/'imntt» are Hat, thin bamlM 
whieh pas.-, forward from tlu- tai^ai In tin- nietiitarsal hones. The tir^t iiietatiirMiI 
bone reetMvea one from tiie iitti'rnal eiineitltrin ; thi' si-eoiid, one from each eunei- 
fnnu ; tlie ihirtl, one from the rvlernal lumifiirm ; the fourth, one from the 
externa] cuneifonn and one fmrn the eiiboiil ; the fifth, one from the enlxtid. The 
plantar ttgdmaif* are more invgiihir, and are stiviiglhened by the expansions of 
the tibialis poirterior and pentuens longu^ tend<ms anil the long plantar ligament. 
The internal cuneiform is eonnerted with the tirst niftiitarsal bone hy a strong 

Elantar Imnd, and by anotiier plantar band with the second nn<] thlnl metalarvul 
rtne«. Other slender plantar bands connect the metatarHil with llwrir corrwi>ond- 
ing tarsid boiiof. 

The iii/c;(wwriHM Hrfnmrntt, three in ninnlier, divide the synovial <aivitie» of the 
tan«o-metatur»al and intermetatarwd joints into three distinct )Mirt>, and otFer 
re*i!*tam-e to di>^rtieuIation at the former joint ; (1 ) A strung intero»«-ons ligament 
pci««'!« from the outer surface of the interna! cuneifonn tn liie coutiguoiif non- 
artieolar portion of the inner !<iirfaec of the witmd nu-tatarsal, and shuts ofi' the 
Mvnoviul eavity nf the first tarso-nt<-talars:d joint fnim that of the second and 
third. The latter aW extends betw<'<'n the l«i-*e:« of the second and third and 
between those of the third and fourth metatarsal bones, mud le continuous with 



256 



THE ARTICULATIONS. 



tliat of llii? wji|ilio-('unfifonn joiiiU, etc (2) Arjothcr iiitenwsi-ous lij^inu-nt 
sriwrjitcfi tin- liwl-dcwHItttl Mvnovinl cuvity fmiii iliui liMwwti ll»c roiirlli hikI tinii 
[iii.'tiitiit'KiilN itiid tlK' I'litioid, l>v ]in!<i<iiif; fmiii the niili'i'ii-cxtcrictl I'l)^- of tliv *'%- 
ti'rnul ciiiiuifoi'iii to \\\v iiiritr MiiHiiri- ol' \\\i'. toiirth iix^tulnrMiI lieliiix) \\» iiitoriuil 
liKiTal liioi't, ami tu tlif ojiiia*!')) mtii-arlii'iilar siirtaoe-i ol' ilic third and tourtli 
metatarsal lioiics Ih>Uiw ihcir articular faicts. This Hvnovial ciiviu- alsto extend.^ 
forward bclwoen the fourth and fifth metaiaisjil bcines. ^3) A slender inieroe»eoU9 
ligament often msses from the inner and front edge of the external cuneiform to 
the out«r side of the second metatarwi! bone. 

I]it«nnetcitaTB!il Articulations. — 1'ro.riniaL — The four outer bones articulate with 
one another lati liilly, and are firmly bound togclhor by >i!uin tntm-vcrjie tlonml, 
plntUar, and infcroiuemiK /ii/fiinntl«. The iiitrrossriiiiii Hyavinif* ('oiiDfct t!ie roiijiU 
nirts of ihe luleml surftices in front of the iirlicular fsiceti?, uiid Jire very stnjn't. 
The li'irml Hifitmrnf between the internnl eiineifurin mid the wcond nielatureul 
tiike?^ tho pliK'c of one bi'lwwn the fir<t »nd ^M-ond me1iitun>al b'ltH-n. betw^-eii 
wliicli there i» often n bnrsii <-()ri'e.'<|>oi)<lin{>: tn iin artteiihir fneel on the lir^t niefii' 
t^irwil otdy. DUt'il. — Tlie di^itjil extreniilii-tt an* lotwly entinerted on llielr [>lHrilar 
asj>eei by four transver^i- luin<U blemlinj: with tlie plantar se^dimoid plate.-*, 'llieiw 
furni till- IriinsfrT/if infiUitnrtKil (ii/nmeiil, wliieb tUtlers from the (iiniilar fltructure in 
th« hand in having a band between tlie tir^t aud second tuetatarval booet). 



i 



CHI HM lis 



rOITIHIO 




BCAPHO'CUhEI 
rOHH LiaOMIHI 



Pin. 379.— The pltnlar Ibjamcnla. (Tcitul.l 



$IiWfmentn. — In the tarso- metatarsal joints there are slight flexion and exten- 
Mon, combined in the first, fourth, and fittb joints with ab- and addiietion, whioh 
■re most free in the fifth joint. In the tar-itwnetatarsul and intermetaiarsal 
joints there are also gliding movemenfi, whereby the areli is altered and the foot 
adapted to the ground and made more ck^iic and flexible 



T. Metatarao-phalanseal and InterphalanGfeal Articolations. 

The rounded heads of the metatarsal bones and the roneavo bases of the first 

^Imlftnge" form arlienlalions similar to llie c^rrt'Npondin); joints* of the hand, 
'hey ai^e couiiect<Kl by lata-nl tifftim^ntM and a thick fibrous jilantar tenmnoiil plate. 



THE PHALAXGRAL. JOINTS. 



The latter is ossifiet! Utomllv in the* gn>at t*>e-joiiU into two afaamoid bona, which 
give attichnieni to llio tli-xor Im'vis toiiduni) and boiind si groove for the long 
Qcxor teiKlon. 

The ptaaUiig«« arliculaf! with one another in the aame manner as in tlie liund, 
and with ihe mme li|^men(A (i. e., lateral and an inrerior or glenoid lignmcnt). 
T1h> M-n>nd and thinl |>lialan|^s, however, are oRcn ossiti^-d t<>|^thor in the foot. 
The dor^l lignmentn of the above joints are prineipully formed by the exteii:«r 
tcmlonK. Eiieh joint liai- a srparnte eynuviul niembrnnc. 

The moraucniti al^o are similar to thoi^e in the hand, except tltat at the meta- 
tar-iii-phnlanpeid joint* extension ti- more free than in ihf imntl ; Inlcrul nxilionM 
(ailihieiioii and alxhirtion) are lew fn-e, and (Jike [)l»tr to and fmm ihv sM-ond loe 
»» a wntre; ami the movements of thu great toe HFC much nioi* limited than 
tbvifv of the ihniril). 

}firtianiiim. — In ualkin^ the heel in the first |mrt of the foot to toueh the 
f;r<iund, and the wfij^fht •<{' the tiiMly is tmnsmiited to ii ihroOj^h the posterior 
rali«m-(h-a.-.tr5igaloid juiiil, ilie I'mH iHing flij;htly addneted, .Ct the other foot 
tiwii^ fo^^^■ani the iiuter Ixirdi-r of the snp]«ir1iiig f<H>t U raised from the ground 
and the weight i^- transmitted to the inner toe-^ ; the foot becomes abdiieted. and 
leaves the ground liy means of flexion of the great toe. In standing, the longi- 
tudinal arch is su[>|H>rted and tlie weight of the body borm- by the plantar and. 
caleaneo-navieular ligsiments. The oblitgue direetiun of the expansion of thp 
tibial!-- po^tertor and (K'nineni^ lonpiw ti'iidim;^, forward and outward and forwaixi 
an<l inwani n-^-iieetivcly, lielp to siipjmrl the lurigitiiilitiiil as well as tin- 1 riinsvi-Me 
areh of the fool. The latter ix uIku supported bv (he Ininsverse phiiilar and 
inteni.sseou'i Itgami-ntH. Tlie heads of the nietatarsal lK>ni'>, on whieh, and not on 
the toi'!', the f<>i>t n^.tts In front, are soinewluit spread out by the weight of the 
l»ody, when the fool is rai»c<l <in tlie to<'.-v. 
II 



THE MUSCLES 



BV F. n. OEEtltlHtL 



Amasde is an onaD whoso essential part ts a ma^ of t>tmt«^ niiiM-iilnr ti^stie, 
prolonged at its opposite cimIs or marfpn^ by vordit, bandit, or »h«vtK of white 
fibrous tissue, whioh are faittenod to other iflnuiltircj*, iwimlly bttmw. TW tniis- 
culur lisstie in coiitnictilc. and is iho iw;tive imrlion of the orgiin ; the Hliroiiit i^ 
strong and fltxililf, but it only ]«L-«ive. TW coiitnuililf- iiortion is mllitl the 
niiMr/r fir'ijiri; thn M/;/. iir tile 't'«/y of Ihr mimrif; tin- ti[>rous extcniiii>n!< lire 
uilh'al r<-N('«fM(>'iiiewi'), iitiil Koi[ii'iiiiii-.-<, whon jjreatiy exjuinded, aponeurtmtii. The 
miisck- projH-r iimy Ix- iioiiiiNinil to nn cnigiiie, in which fnroe is eenerated ; its 
tendon.4 to the n>iK'j* by wfiieh llie power is applied to distant ohjecte. 

Tbe relfttton of tbe t«Bd<ms to the body of the mnsclo varies grcutly in differ- 
ent miifeli-s, l>oili a^ rc^rils their proportion nnd their arntngement. Tlie Iwlty 
mav have lendinoii-i striietiire oiilv at its extremities, or one or b«tlh of the ten- 
dons may ttlart far haek ii[>(>n the surface of the eoiitnuitik- niiuw, or u tendon 
may be in lai^ part eonoealetl in the midst of the niiiseiilur fiTWiie. Several 
plates nf tendon may be thus embedded, all eonnect^d with the turininid eurd. 
When the tendons are flnmd only at the ends of a mnsele, tlic fibres of the two 
kin>hi of tissue are suits tun lially in the same axis : but, when one of the other 
arran^ment^ obtains, the mii>ieulur fibres are planed lit nu uii^le to the temliuous, 
as the Uirbs of a feather are related to the qnill. 

In a few ninseles there is a tAint Iriutnit midway of i(« contraetile mass, which 
is thus divided into two. becoming ihinhli-hill'iftl — in teehnieal phrase, <ii'iii>/rio\ 
nr hirfotml. One or mor^- narrow, libnin* iiiterniptioni>, {utrlial or complete,' 
may oecur in >*omt^ ^*>'*K nin«eleii, eoiiKtitiiting temiinmut tnMTijtl'umii, 

Boua in Teadons. — Small oMt^inu maA.'H?', eidliHl Kemitn'ml ("like scsjune") 
bottm, are somelime-i devi-l'iped in tendons at poinl.i wln-n- tlu'V play over joints 
an<l an- exjHHi-d to jrn-at pres-iure, Simie of these are eiinntant, as the piiti-lla, 
wliieh is a nesamoid bone in the great miisele whieh straij;hl<?ns tin- leg on the 
thigh. 

Synovial 8h«atlia of Tflndons. — Svnovial membrane of the vaginal form is 
developed around many tendons whiell run in canals, as in the ease of various 
digital niu^'Ie^. liunul i«yno*'inl mnnhrunfM are found at very many spots where 
tendoiLs pn-.*f iHH>n one another or H[«>ri irthcr organs, especially where they pass 
over pn >m ! IX 1 ■(-■■» of hone. An nrtifulur nT/m/rhif mrmbnmr may lie pn>loiiged 
b<-yond itj< joint, utKl furnish a Inbrieuting vheatth to the tendon of a neighboring 
mu-sele. 

Attaetai&mtts of Tendon*. — A Irndon may l)i> lon^ or short ; it may resemble 
a ooni, a ribbun, or a kIk*!-!. In the litst ease it i.s I'onniionly eallisl nn n]Him'tt rusts 
— an umle-siriibte, because etymotugieally misleading, name, but now firmly fixed 
by eminent «»iierion. Tendons are [isiially fastened to boners and eartilap*s, bnl 
may be attaeliwl to ligaments, skin, and <)llM-r si>ft iiarts. The fibrous tissue of 
the tendon interrainglfc', ami Ijecomes continuous, with the periosteum of the Ixini;, 
the perichondrium of the carlilage, or the deep layer of the skin, thus blending 
witli a Htmcture which is liistologically identical with itself. When one oon- 



260 ^^^^^ THE JfUSC'LES. ^^^^^^^^^^^ 

siilcTH till' iiHimni'y "f n-liirion )h-uv(H'ii ]M'riiir<U-iiiii iiiiil 1111111-, fii' ii* nnt surprised 
at llu- intifc|iuTU!y "(' tli« ."L'luinttiou ol" u ti'inloii from ii.% ov't-ous aMni-limt-nt. 

Proportionate Increase of Tendons with Age. — Tho U-iKlinoiiii imrtion tyf a 
mti:«i'li' iiK'i-tiLTs with yi'itm, iiiul on lliin iK-i-imiil tin* musrtf^ nf ao attull an-sttfl«r 
rhiiti llioj-f III' a cliiW, ami tht' raiij^e of joint-movement is dim in is hod. A cltild'? 
cxIi'ikIi'iI Iowit limb may Ix- kt-j>t at a right angle with his trunk for a long time 
withont (iiiiHing him any discomfort ; but the same procedure cannot !» prac- 
tised iijwm an adult withimt pi-otlucing great snlfcriiin and pcrhiips injury. 
The difference is due to the normal mus<^'tilur extensibility in the infant on 
the one hand, and thi> cfjiiully iiurmal tendinous iucxtcnfiibility in the lulult 
on the other. 

Oriffin *nd Insertion of Muscles. — A luusck- i« attnohcd tn two ubji-cttt, nod by 
lis fonlraelion lessen" the di^l:lnl'e lielivicn them. The jiiirt wliieh is Itwicmt! to 
the more Jixetl of lh««r <>l)jei'l.-i is eiilh'd ihe oriifiu, the olher the innrrtinti. The 
<>ri(;iii is generally, esjK'ciitllv in the liinhs, jiroximnl, the in.'u^rlion dixtid. Hut 
tile tornis an- entirely physiological and lai^ly eonvenlional, for in ease of many 
miij^lo* there is room for ditferenee of opinion as to which jmrtion is t]ie more 
entitled to be called origin — the action l>eiiig a» frcqiiejitly from one end as from 
the other. 

Fascie. — The nuiscles in a region are maintained iii close relations with each 
other hy strong sheets of white fibrous tii^ue. which are wra]>[)ed firmly around 
them and oHen send shelves Ijctwcen them. These Iibr<Ris expsinsions are willed 
t'uwla- (" bandages "), and also aponcuroiwJt of' imrxtinnit. TheV will be dtveriK-d 
in detail after the muscles have been eoiisidcn-d. It will witti<'c here to reniurk 
that it i(( eoinnioii for niuneles to have extensive attaehmenttt, either of origin or 
iiwrtimi, to the fsiseia- whieh cover and scpanite them riuni their immt^^liMtc 
iieislih'Ts. 

Ligamentous Action of Muscles. — The ninsele.'^ perform 11 valuable iser\'iec in 
keeping the enrtihiginons (^nrfaees of llie inovnble joitils in eontiiet. The liga- 
ments projK'r are in many ciweji utterly iiiiidc-iiitiUe for this work, us witness llic 
joint Ix'tweeii the shoulder and arm : riMiiove the nuiseles and the hiuiieriis drops 
HWiiy from the glenoid fos,sa. Hut the iniHeh-s, whi(-h ucniniilly are never fully 
ri-liixed, keep u]i a tirt-less pressure, ami, excepting violent «ec-ideiit«, never allow 
a sijiaration to occur. This unvarying normal tension of niii^eiilur lis.Mie i.-. an 
olislacle to the reduction of fractures and dishwationH ; for as s<ion as a hone iit 
thrown out of its |>ositiou, or a breach in the continuity of its .siibstanec occure, 
the neighboring muscles, in demonstration of their being constantly somewhat 
tense, pull the luxated bone still further out of place, or cause the fragments to 
overlap each other. The muscular furee is often »o great as to require much 
strength, or ana'sthesia. or both, to overcome it. 

The HechajiicB of Muscular Attachments. — The [>oiiits of attachment of most 
ninwcles arc i^ueh a.s to place these organs at a great nieclumiejil disiidvanlage. 
This i.i very evident in a liirgi- jHirt of the muscles of the limbs. Take, for 
example, a mu.s<rle which bends the forenrm U{Hin the arm. Il is attached to the 
lower half of the front of the humerus, cro««^'s the elbow-joint, and just below 
(hi,H is attached to the ulna (Fig. 2S0), The los.^ of power involviil here i.s illus- 
trated in a homelv way by comparing the effort i-equired to close a doi.r by pulling 
it lowani one, when it is grasp<-d at a point near the hingen, with that whieli 
suffices when it is seized near its free edge, where the knob is usually placed. 
Manifestly the latter method is vastly easier. If the same plan were adopted in 
the flexion of the forearm, the muscle would be attached high on the humerus 
and low on the ulna (Fig. 2^1). But, although this would be advantageous as 
reganls the expendiliin- of force, it would he strikingly otherwise in directions of 
miite as much imjMjrIiiiice, In the lint place, the e«nlractiou of muscular tissue 
)diorlens it lo one-half it.-! length and no more, on which account the forearm 
couhl be bent iipiii the arm only to |{. insl<^ad of to a much higher jM)int, C, 
which ii normally rciii^hcd. In theseeoni) jilaci^, there would be a loss of rapidity 




— _ -U 



pniMARY, SECO.VnAItr, DIRECT, AXD REVERSED ACTJOXli. 261 

.at movement of Ihe Kiwit <'nil nf flic limb iil>i>iit iirri|»ortii>nntc to tho jtain of 
'■^limTr ; fur l\w umnT In llin Winff- ihc force is upiiiKd, (in- tiiore rapid will Iw ihe 
mov<.tni-i)t of llie long arm nf tlw Ii-vit. Tfun, the <x'cii|i!ition l>y the mumrlo of 
wich iimfviiwivi? iwrtion of tJ»* gn-al Iriaiigiiliir spiu% itioliidfil bv it uiid tin- two 
bonot wlit-n iii flexion wouUl be an intitlorablc intt^rR-ri'm-e with t.iiv uscfnlntrss of 
the limb, practically rtilucing the cnrryiug [wwi-r of tin- fruiit of lh« fon.iin» to 





Til.. 9a~I><iiar«n diwlmt thi- mrrhanim 
•liMdvuotmer of ihc potnli or BUochment of 
mtai miuclo. iF. n. O.) 



Ti'.. IMf-naimm Aowlac Ibc cAet «ri . 

!■««- If, H. «,r 



nothing. Thorc wonld a!.*o br- a lii-w of ii (jri'^'f 'I'"il "f the imporlaril Iifpi- 
nK^'ntous work of tin- imiscli-N by their n-moviil fmtn <l<j«i- (-.nilui-t with tlir jtiints 
(hiring their most pmnouncecl uetivity. Thiw it will Im- m-vn Ihiit the <'ondirioii 
whivh cxisl(^, whilo extremi'ly rosily in thft mutter of nni.-u:iilur ex|>ei)<Iitur<*, w 
utti.-n<]e<l with advantages whieh are more than «'iini[>('ii!*atory. 

Change in DiractioD of Muscular Force. — IViidons art- often inad<- to jiass 
nroniiil pr<.>iiiini-nci"i snA ihrough loops, the foree originating in the muscle thus 
exjK-ricncing ii chiinpc of direction, as in the case of a rope which runs from an 
engiiH- tlin>ugh a pnlley to mi object which is to lie hoisted. Tile eontraetilc force 
of siirh a iiiiiKeIc \» applieil in tine with the portion of ito tendon lying between 
the fcksl angle which it niidii.v rinil (he point of its attaehntent to the object to be 
moved. On anconnt of the luiinnilion of the tendon by synovia, which is always 
present ill sn<:h e.isew, no appn'ciuble !«« of |>owcr is ex]KTiciiced by the change 
of (hrcction. 

FtiiBM7i SeeondaiT, Direct, and &«vers«d Actions. — A mii.'ccle which enK^es 



262 



THK MVSCLES. 




y 



y. 



/si 



^^J 



V:i 



only one joint has but two poseibiliticH of action : ono, which may be called itt* 
(?fjTc( action, is from a iixcd origin to a niovabic insertion : thf ()th<?r, its ivrerxtil 

ticflfiii, is from a (ixt'd iiiM^rtion to ii m'lvahip origin. 
But niTiny miicrUs r-ro^j' two or more joint!*, anil by 
w> niiicb is till' miiiil«'r of their movcnirnth aWtf- 
nicntwl. For ini>(:iiKX-, ibi- MiiR-rficial ilc-xor of the 
fingcrn iirinmrily mid diri'clly flexes (ho second phal- 
iinfTi's upon till- tirsl ]ihiiliiiig('K (Kiff- 282, A); but, 
wlicii t)ii.>< miivt-moiit i> coniiih-tiil or is prevrntcd, 
I'oiit iiniiinco of the poiitrai-lion ciuhcs flexion of tho 
limt plmlnngc.s uitou ih<- mctai-arjial boii(->, hikI itiU 
may ["■ tiiltcd the rlircct »fcontlnri/ itctiou (Fig. 282 
B). Wh(?n ihiii niovcmont is aeooniplixhcd ()r iir- 
rcstcd, still further contraotion pi-oduoos A<>xion of 
the whole band npon the forearm — tho dtra-t tertinr*/ 
action (Fig. 2S2, C) ; and, finally, by persistenw in 
tlio pcrformancf, ihc f'orrarm is flexed sli^-httv nnon 
iIr' arm — lliv rlirrrt tjiiulatHiry mtion ( Fig, 282, T>), 
TIr' rov<'rs«l aclions in thew various (iiage:^ arc too 
obvious 1o irqiiiri' d(.vK-rii)tIon. 

Tho eognK'iit of » )iiiil> mi wliioh u mtiwle acta 
ojirrifs wlln it, of oonr^c, nil ..f tin: i«irls <\UUi\ to it; 
«nd lli« niovcnunt <-Hi-ilid by thit eontnu-livn of fho 
luiiM^li-s in nion^ manifcHt it]K)ii (Itosi- piirt-c iliaii iijwn 
the segment lieariiig ihitii, ftim-c tliiv df-M-ribi- larger 
aivfl. This is ptirticularly noiieeable in the jironn- 
tion and supination of the ndins. Tho otuitigo in the 
relation of the lateml jwiris of the forearm iji lisr 
less apjuirent than the alteration in the atTiliiile of 
the hand, which iMis^ively aecomjianies the nidiiix. 
The Blending of Muscles. — Atnselcs are often n»«>> 
ciated in groups so intimately that, either at origin 
or insertion, there is an actual blending of substance. 
Myologists have not agreed upon an absolute rule 
for the r^ettlenient of the (ptestion of divisiuu or uni- 
fie:ition in these eases, some describing ii!s two or thivc dii^linet muscles what 
<nlKrTi regard as a oomiKmnd one. There U niucb in this eonneetion which is 
eoiiventioiial and arbitrary, and, consi'ijuenlly, iK-riiU-xiiig, 

The Muscles in Pairs. — Almost all of ihc skeletal muscles air arranged in 
pairs, and ihuj^ a description of one on cither side will answer for its rontc on tho 
0|i]Hir4ifc side. A fcware i^ingli! and located about the mitdinn line, and iu 1hi!8« 
tnei-c ill gi'uendly a bilutcnil synimetiy. 

Tbe Sise of Muscles varies fivini a fmction of an inch to nmny iiielics. fn 
form iliey art- cxln-mely diverse, and only in a small ])roiMirtiou 1.-. their ri-scm- 
blance to familiar objects sufficiently striking to justify the application of nitinctt 
intended to he descriptive of their shape. 




Fin, 3«.— Wimtmni ibowtng tho 
primary, icrvxidkiy. WnlBiT. etc. 
■ClIoIU of > lUlllH'lC. (P. II. u.) 



The Nomendatore of Muscles. 

Latimty of Kames. — The muscles arc almost always called by (heir Latin 
names. A few have lH.vonic Auglieined, eommonlv by thi.* omis-^ion of the ter- 
mination (as •fcftiiiil instead of ilrKoiihiiK) ; but t(i<' attempts which lia\e been 
made to displace the Latin appellation!^ by substituting English translations of 
tliem have always failed, Thu "tudent, however, should learn the exact meaning 
of every name, as tins kiiowUilge eiiniiot fail to be of gniit assistance to him. 
For example, almost uno-lialf of the luuucs' of the muscles moving the iicvend 



SAME6- OF MOVEMENTS PRODVCED. 



263 



!«^mititi4 of the upper limb, atv descriptive of the action of these muwleit, and 
nwirly iwo-tliinLt of tliese convey rtnuc uii<litionnl in forma lion— of form, liitiis— ' 
tton, or Hijw. The majority of llic iiiimc-i of the other hfilf of thin j^roiip in<]i(^te 

ttOi'ition, aiiil the residue mil attention to i^nie chnrocteri^tiu of sha]M' or resetii- 
ilanee. From this it will be «xn that the immes arc Dot arbitrary, hut any 
de^'l^ed to be dcwriplu'c, atid, c<iii?>ef|iii-ully, arc helpful in the lir«t Imruinguml 
in the {icmianent rctdilion of thi; fat'ti'. 

The Lntin won! m\i»rniu» (" inu.><I('") u alwwy.s impUcil in the nam*' of a 
muf^cle, and Uic (Mirt which xrt ex[>ri'!«(*<l i:* eilhvr un ndjcfiivi; or a iioim in apjw- 
sition, with nr without litiiitin^ wonR 

Beaaons for the Names oT Hosclea. — Mu^oli^ are numed from vnriuns eon- 
niilcmttono, and occanionally more than one of ihctx! \» appended tu in the 
ei'lctrtiou of a name. It is noticeable that the nameti of imlividuals an- not 
used in the nomenclature of musolee, an they are in almost every othor branch 
of anatoinv. 

The tollowing arc the princi|Mil derivations of the names of muAclea : 1, ari'um 
or sn])))oi^^l action, as levator •^cnpidic, " the Hfler of the shoulder-blade," supi- 
nator, " the muscle producing euptnutiou" — turning the part onto ito back; 2, 
/arm, aa pacilis, " tiie slender iniiwU'," soiratus, " tlie mw-tootbed muscle ;" 3, 
tlie Jonn of two mtuu^lm i-ymmclriwdly liK'^ited on opiKi?(tt<! sides of the body, as 
trapexius, " the tablc-bkc mn^olc," though nivb lra]>i'/iiis i» nut tni|K-»iid but 
trian<;uh>r ; 4, rrnnjiMimv In « niilnrttJ olijtd, a» liimbrioulis, " the earthworm 
mnsele." iwlcn*, " the i^oU--fw!i mti«ch' ;" 5, nituattnu, ax fronlalU, " the forehead 
mii3«ole," iiulxdaviuH, " the ninwie uiuler the eolliir-bone ;" 6,iiltitf/imriil)i, an coraeo- 
bnirhialiK, " tlie niiiM-le nonneelin)^ the corueoid prvxH-w and the arm," l>nu-hio- 
nidiali", "the muHcleoonneetingthi; ami and thiTudiun ;" 7, Ara-, cither alMolute, 
n* viistu.-i, " die fin-at muscle," or tioniparative, a-* lativ^imnn, " the bniad(t<t mni^- 
eli-;'" 8, 'lieUion, a-* quailrieej», "the foiir-hejided musde," inidiifiduo, "the 
mii.selft of many elefis ;" !*, jHtii-eil ifmitilum, iw ^eiHrllnM, " the twtii mii^-le ;" 
li), mipi>ii*i^l ihiiflriiiMHian ar.ypy* iivuW, " the uvula nin.tele not yoked toa mate ;" 
11, inrtiieemntt of iitnitiutt; a.-* comphxim, " tlie oomplioated mu^-le;" l'2,tiirfiwn 
o/filire«, as rectus, " the straight muscle," transversal is, " the tran«ven>e mu«'Ie ;" 
Vi, rf/nlieif proportion of coniraeii/c and non-contraetifeti»iufti, as seiiiimeinbnUKv<iis, 
"the half-membrane nniwlc," semi tend ino^us, "the half-tendon iniiwle;" M, 
existence of a tendon utidtcaif lirtirrfii hi-o cnntrtietUf portiotin, as di):u:*trio Qn<l 
biventer, " the muscles with two bellies;'' l'>, ofnipfititm in which the mn>eh' 
is thou(;ht to be iLseful, as scirtorius, "the tailor's muscle," liUfrcinator, " th* 
trumpeter's muscle;" 16, rrpiyv»inn produfal, tis risorius, "the laughing mus- 
cle ; ' \~, tJte aubordiiMic cA'iMK^rr of tfir work donr, as acoBgauriiis, " tlie assistant 
musele." 

Namei of Uorements Prodaced. — Moft of the movements of the parts ujwn 
whii'li inn-<-Ii's act Imve reec-ivi-d •■piTific names, ^mie of wlueh arc applied al«> to 
the attituditTt r<'--iulti:it; from tlii->e iimvement.-i. When loic part is W'lit ii{H>n 
another, the movement is oaltwl jtixhit ("a landing"!; when the purl is 
strai^ihtened out, the action is extennion ("a stw^tchiuf;") ; and that* llexioii lutd 
extension are anta^jonislic actions and attitudes. The movinij of a [xtrl further 
awiiy from the middle line {the median plane of the whole body beinc meant, 
unless otherwise ■ipccitied) is obditrtlnn (" a ilrawinj; from ") ; the ojiposile move- 
ment, by witieh the part is restored to its former position, is nddiirtion ("a dniw- 
injjto"). The slight difference iK-twecn these anti]>odnl wools should l>e noted 
— the one bcf^ins with tih, the I>atin for " from." the oiher with «'/, llie l^itin for 
'* lo." Wln^n a )>art is nia<le to revrdve upon its long axis, the mo^'ement is rrrfo- 
tion, ("a ivvolviiif;") ; and when il« lower extremity is eause<l to describe a 
eirolc, and the piirt itself thus tniverw-s llie pi'riphervof a etjue, the action is cir- 
cE(i»</«rfiflM ("a dmwinjr armmd "). The nioveim-nt which tarns a part onto ils 
fac« is proaatioit (" a l>Gndiug forward "), and tlie reverse U vapiiutlian (" lying oo 
the back"). 




264 



THE SfUSCLKS. 



The Ord«r of Stndjr. — Tin- imwirlc^ will be (rnnsuU-rtHl in flu- folluwiiip otmf 



The mils 



li" Till-: ri'I'KK I.IMR. 



i 



Till.' miiwli-^ iif TTir. UIH'KR I.IMR. ^M 

TIk' IMIMi'lcs of THK TKIN-K. ^^^H 

■ (rf) tiioM- of tM tinrk, incliiiliit}r tbo (]on<URi of th« neck. ^^^H 

V (A) \\nMn- iii' the iihiiomeu. ^^^H 

I (r) ttio^* of rAir thortix. ^^^H 

K Tlu^ iniinclo^ of TiiK nkck, at tb« front ajicl M^ea. ^^^| 

" Tlio nilisclt-s of TIIK lIKAIt. ^H^l 

Tlic iniiiiclew (jf the tonf/ue, )ihnriin.T, nnd xoft paltdc will ho prpMpjitotl in win- 
iietrtion with the organs of (lig(.>)^tion ; tliosp of tlio larynx: witli ihe rcspiraioiy 
syatetu ; thosp of the cyr and ear with special senwi organs ; and thoso of thefl 
peri'nrtim wilh the gt-nitals. ^ 

Ulustrative Pictures are ])roviiir(I so lilK-nilly in tliiit oliniitor. and show certain 
dctaili' wo i-k-arly, thiit it is ]inicliivihlo to omit frnm Ihf verbal dix-ription-i many 
ttiingi whi<'li arc usually given in thviii, siod lhi>'. too, mil only without diminu- 
tion of elfiirni'-o-, lull ofli'ii willi distinct advaiiliip- in tliin rcpinl, ^iitfv fwctf^ can 
iiHiially be inoi-r auiikly ii[i[)n-tK^nde(l and more finnlv lit-lil when pn^vented bv^ 
liif-tiiriiil mi'uii", llian whcji introduced into th<> miiul thmngh the iiiedinin in^| 
wonls. Thii.*, the form of a muscle, the most important relations of its eontmctile^^ 
and tendinous portions, and it;* princi])al relations to neighboring miiMdcif arc 
p-nerally shown so plainly in the drawingit of dissections, that their descrijitioa^ 
van safetv ami prolitalilv be omitted from the text. ^| 

Th« Outline Drawiogs of hxHndtin/ mi/Jir/fj" nhotr in ffieh ivufancf (hr focaHon 
atid pfopiirtlouiiti: isi>: of the areue of oswo(m origin and (Hscrfioii, ttiid al»o Ihe 
marffiiui of tJie rntire mnnclr from (he Kfleritd point oj vtev, thug miggftting Ht 
action. Jn <^wv ir/im- n mirfari' of atfnehvinit or n pnii nf t/f oiilfiiir m not rigiftle 
from the rho»ni p'liiit, tlie voiirriiM pur/ton in ilriiini in (IiiIk or /mkai linr, and is 
repreiieiifed o* if llu- iiifen'cnuiff iikfUliil ntnwfHiv irrre trow/ipareiif, S 

Minuteness of verbal description of mnsenlar attaehments, while morphologi-V 
cally intercj-tiiifT. is of little or no pinrtieal value to the physieiim and hurgeon, 
and, eonsifptently, is not nltemph-d. The esK-ntial faets are presented in tlio^ 
text, unci in most eases are abnndaiilly illiistrat<i:l in the onlline dniwinup:. fl 

Conaection with Neighboring Soft Parts. — Thr itKaektneidi' In mijirrjucnil /(tJifi<r, 
intrriiiiiiifiifiir "'/iln, •mil nlhir xufl jutrU trill iiflrii lif uinilteti /rum llir Irxl for lilt 
mikr nj lirrrilif, ritprriii/li/ irhrii lUrxi' are of i imii/ii ifieii lit ej-tfiit, or hiirr ii/mttly hfrn 
mrntiiiiiiil in r.imnfi'fiini irilli tlf f/iti\ij) of rHi""Vi« fonr^'iir^il, ll tii'ii/ inniiillif tt€ 
aiuiiiiii-d Ihiil tt iiiiiiirff hfm noiii' iifh^'imn I'l l<i ihe fibroux utriirliirtu — iiirfnliur/ iJufif, 
pitrllliotiH fieliiv^H it and itn iiuiiudiiitc ,i<iyhhor», Ugamnit-ii, rie. — with whirji H in vnm 
iVowf i-itillilrt. 

The Action assigned to a nmsele is that elTeeted by its eontnielion from a fixei 
origin to a movable insertion — tlie direct primary aetlon — unless ollierwtse s]ie(!i' 
fied. The direct secondary and all reversed actions can be worked otit comn'tly 
and easily by one who liari learneil the direct primary action and the anatomical 
reasons for it. fl 

ClassiflcatEoa of the Limb MuscIbb.— The ela.-silic-iition of the muscles of tlie 
limbs which i- here given ts phv>i<i!iigical, being bat'ed n|Hin their ]irimarv and 
nio^t chaiiicteriHlii- iielion. .-Mlhoiigb ihis giiiiipiiig is very ditrert-iit from (hut 
which is gem-rally fallowed, it i> believed to be nn.n' useful as an ai<l in Icnrniiif; 
the iJict.-« of gri'alesi importance in myi>l>igy, and in applying the kmiwliilgc ihiia 
gained in medical and surgical lu-adice. Of course, it in not claimed that tins 
elassiHcation is perfect — none which rests ii]Kin a physiological basis can be ; but 
long employment of it has demonstrated its utility in attracting and huldiag 
the interest of the student, and this nniinly iR-causc there Ls kept eoii,>.taiitly 
in view the application of the facts which he is learning. After (he muscles 
of a limb have been described, their eliissificatioii on a regional basis will l>e 
I>niKint(Hl. 



I 




THE MUSCLES OF THK rPJ'hIi LIMB. 



265 




■ THE MUSCLES OF THE UPPER LIMB. 

H Movements of the Upper Limb. 1 

Each of Uir fwir |iHmurv M^iiii-ntj< of the iipixrr linili U mpAblc of n wide 
nin;ir iif anion. 

HoTcments or the Shoulder. — In the ohnplcr oti ttio joJtiLi ihv Mr]i|>iilii U kIhiwr 
U) )h- MiitK-aluil tnovnlilc iijHiit ihc t-lavicle ; Init, in Mudvirij; the iirinciiml iirtion 
of ihe nnL^l(-s, ih^" niovpnuMits of thfi riaviciilii-ncromial joint may !«■ ijjiion-d wilh- 
oui ^tfrious departure from the fact, ami the nkolotnii of tlw- choiilclt'r may \te 
repinled as pradically a wingk' hone. Tills framework \s pivoted upon the tnink 
at the fiterao-clavicular artioulatioit, and is pn>ximany Httaclied at other points by 
muscles osly. The movements of the $h<iiihkT, therefore, eetitre on the up])er 
end of tb« sternum, and ure niude upwanl, downward, forwani, and haekward, the 
tvnu'^ uswl to<!oi;rnate ihem — i'k'V«tion,dfpre«*ioH,etc, — rw|nirinp nooxplaniitioii. 

HoTcmcDtK of the Arm. — TIk- ann, Iwinf; nuiltil to tho ^houkkr l>y mcjin» of 
a bIdI^lml-^il■t■ket joint, ean be muvwl in cvi-ry dini-lion which is tfiiwii^tt'nt with 
the intejrrity .if tlw nrlicular struelnres and with tin- rct4'niion of the Iiitmeml 
head in lliv I'h-nitid f(K<.->a. liri nii)v<-m(-iil forward is y/cj-ff>ii, Imikward i>t «rfrn- 
«i'on, out\timi is nUdnd'xrmy inwnni Ik addaciion. When it is rolled on itft nwa 
ftxiii 80 that it« front tnrntt toward the trunk, the mnv<'-ment i.4 imtartl rolnlion ; 
when it n-volvft* so a* la turn its front away from the trunk, the action is i-xlemal 
jnlalioii. Its nrrumflurtioH is iutenril when the fnnit somieirele desortlR-<l by the 
lower end of ihe arm is made fn>ni th<r outside to»vard the mid-line, and llie op|>o- 
siie movement is outirard chcumdiiriiott, 

MoToments of the Poreann. — The elbow-joint proper is a Iiinpe. allowing 
motion between the forearm and arm only forwani, wiiich is^&rron, and baekH-ard, 
which is txteuMton, Between the two forearm bones, however, arc movements which 
winsist in th^ overlnpiiinjr of the ulna by the radius, pronation, and the opposite 
action by which tho parts are restored to their anatomical attitude, »iipinnttou. 

Monmenta of the Hand. — The articntalion l>etweeu the forearm and cnrpiis 
permits motion of the hand forward, which is _/f«-iow, backward which is exten- 
mon, sidewtsc toward the mid-line, addudion, and from this line, abdtiti'um. Cir~ 
cumduftion, which is accomplished by a combination of thes« raovementa, is 
inwanl or oiitwanl, acconling lo the ndr p'ven above. In tliesc various move- 
ments of the whole bund mmic motion takes jjliw^e tn thi' joints between the car- 
jwil honii« ; but IIk-k*' arc so "light tw to In- pmctiadly in:ipjirecinblc, ami require 
no ftirther m<-ntii>n. 

HoTomenU of the Metacarpal Bones. — The tffond, third, nnd/nMrf/i mtiacarptd 
Wm** arc »> firmly join<><l to the carpus that but little motion ii< posnible, evt^ 
when their n-spi'ciive difrils arc ino-i forcibly ncti-d n|>on. The JijVi uultiettrpni 
iHinr luLs an apiini'luble forward movement, which is Jfcj-lon, a IiaekwanI, which 
is eiteimon, and ^lijjht lateral motion^, nMuHi'in anil uddiiftiim. The _)i'rA( inrfrt- 
pftr/ial is .so articulateil at the wrist ihiit its range is v<-r\" KwiU, and this fn-edom 
of action is moi-e than a compensation fi-r the deRoiency of a plialanx in its digit. 

ICoTcments of the Common Dibits.— Fr»rward movement of the yi»9^nt and of 
each of their piwdangesisyij-iVjji.nnd backwanl movement Is «rf<rH«i)j|. The lateral 
movements of the fingt-rs art- eulleil ahdnctioti and addiic(!o)i • but the median line 
of the body is not here taken as tht* pliine from and t(i which the action is reckoned, 
a line drawn through the middle of the middle fiuKcr when it U in rei«iM' being 
sidi»itituted. There is pnielii-idly no Intend motion at the interphaltinge.Tl joints, 

Hovementa of the Thumb. — It is to lie partieuliirly notice<l that the fin«t 
nietiii':ir|iiii is s» pt;ieed that tlie tliiinih is in advance of the |dan(* of ihe other 
digits and it(« palntar a^iK-ct in about at ii right angle with thein*. ('oni<<->juently, 
a beniling at tlie joints of the thiinih toward its jmlmar aspect, which is flfxtun 
(as in the wise of the other digit*), causes it to crows tlie i«i!m of the hand towanl 
the byjM>thenar croinen<w, 'fhe rwtcjriiig nioveinvnt \» cxttneion. Ahdutiiun of 



266 



TBF. MUSCLES. 



the thumb is in the direction of flexion of ilic fingers, and its addaiiion ia iu the 
din-i-iion of tlicir extenition. Its circumduction recjuireH no especial deKcriptiou. 
It will be ob-^rrvi-d (hat, fmni the I'huiilder-Joint down, llie/orwarrf moreutftiU 
are Jtr-ri(ni», iiiii] \hi^ Imrhrinyl movniicut« are extmifWiiK — the thumb offering the 
only exeeptionit. In th<F lower limb lhi« rule doeB nut »|)ply> 

Cl^aSli'ICATIOS OF TllK McWl.fi* OK TIIK I'l'fKK LlJIH ON THK BA8I8 OF 

TKiiiic I'l!I^<■ll■Al. Acno.N. 

Moving the Shoulder. 
Upward and bachirard. Doirnu-nrtt and fwvard. 



Tra[>exin8. 
Levator geapulie. 
li homlmideUH minor. 
Klioiubtiideus major. 



Ahdiidon. 



Pflloidcus. 
SupnHipiimtuM. 



Serratus iiitigiiiis. 
PeetopalU minor. 
SubclaviuH. 

Moviiig the Arm. 

.Uldiiffora. 

Peeturatis niaior. \ , „ 

Corjieo-brnebiaiiH, j ' 

IjHtisHitnur-. I , , 

rr ■ / nun erhnmrs. 

T«.Tc» ninjor. / 



Inteard lifilatw: 
Subiicupularii). 



OtUieard Rotator*. 
Infrnspinatus. 
Tcrea minor. 

MoTiBg the Whole Forearm. 
Flfxora, J-^im»arii. 

Bleeps flexor cubiti. TrieepH extensor cubit!. 

Bmebiiilii;. Aneoneii!). 

Braehio-radtali»). 

Moving the Outer Part of the Forearm. 
Proualinn. Suphitilor, 

I*niii(itor tere». Supinator. 

I*romitor fjiwdratiis. 

Moving the Whole Hand. 

Ftrxorn. h^rrumr*. 

Flexor rarpi radialid. Kxteni^nr earpi mdlnli^ Imigu^ 

t plexor] julniari.H longii.s. Extensor earpi radiiilis brc-vis. 

'lexor carpi ulnari^. Kxteiifior eurpi ulnarLs. 

Moving the Fingers 
and th« Flftli Uetacarpal Bon*. 



Flrxnrf. 
Flexor MiblimiK di|fili>riim. 
Flexor prfilnndiH difritornm. 
Tlevor *iivt\n nii-l:irarpi minimi digili. 
'Flexor bri-viH minimi digiti. 
•Lunibriealew. 

AMiidor*. 
•Intero-Mici dorwiIeH. 
*Ahductor minimi digiti. 

Moving the Thumb 

and its Metacarpal fione. 
FIcTorn. Ejifittori. 

•Flexor onsis metaoarpi ptjIHcis. Extensor nrs'in nietiiearpi iMilHois. 

•Flexor l>revi(t [Hdlleis. Kxtensor breviB gmlliciti. 

Flexor longuK |>olliciri, Exlenm>r longus pulUoiii'. 



I-^tenttorti. 
Extensor eommuniw digitnrum. 
Extensor minimi digitj. 
Extensor indieis. 



Addiictora. 
•InteroMiei jmlmurcs. 



^ J 



MUSCLES MOVIXU THE SHOULDER. 



967 



Abdtielor. 
'Abductor poUiciH. 

■ IJitiMIMTMUiPily in tbo hand. 



AildHtiar. 
•Adductor pgllids. 



MUSCLES MOVINQ THE SHOULDER. 



Ufocani and Imchcanl. 
Trapezius. 
Levator i>capulfo. 
K)i()mlx>i(lcii« iiiiitor. 
UhumbDidinis niujor. 



DuKnitmrtl ami fonnirtL 

FvPtoralin minor. 
Sul)clnviu.'<. 



All 111' lh<-j>i' mii»oleA «rijH> from thv trunk, exeppting one, whieh han its origia 
in the uvcLc. All are io^rtf^ into the skeleton of the lUiuuldiT. 

Tnp«slii8 (Figs. 283, 284). — So called from the rcsemblunce wliich it with ilA 
mate bear> to a four-sided table (Greek trapesa, " u tabic "). Ht/nonym, cucullariii, 




1*«T THOm- 
«I0 VtaTtBDA' 






no. 2S3i~liloBCl« in (he luprrflrml lajri-r i>f tlm htiA. (Tmnl.l 



from thv likenesa of the pair to a nionk'n lt'K>d (Latin etM^itl/iU). Sihtnticn, ituper- 
ficial, un tltv dor»il aspect &oni the oeoijKit to thu ba«c of the thomx, and lat- 



268 



THE MUSCLES. 



cnilly to the poak of the sIioiililiT ; aliHi, at the «hIc of the neck, und the lop 
ami fnmt i>f the shiiuliler. Orii/m, the inner third of the i^uperior ciirv«l line 
ami llie iirdtiilnnince of the oceipitnl lK>ne, ihe liffamentuni iiiiehic, the spines 
of lhi> l:L>il ccrviinl iLn<l all of tin- ihonicic: vcrlehra'. iiiul ihi'ir MJiinti']iinoti» 
lij^iiuicnl.. Dirivtiiin of tihres, onnvfrm'til : l!ie ii|>}kt, timvii-, out-, anU ftirviurd ; 
thi' TiiiildW, oiilwuni ; tin- lower, u|»- and (iiitwiini. IriKntiou, the owter ihirxl of 
the hind hordi-r of the daviole, th(' inner border of the acroiriion, the iinp<>r ix>r- 
derof die scapular i<pine, the tubercle near its inner end. Action: tne upper 





Fin, isi.-Tnpedai of risht ddc ; ootllne and 
■lUrliiutiil imai. (F. K. Q.i 



Vie. iK— Mu»ptci III iiir (Wind iBVcr ontic b*cli 

&nd oil ihi! d<inui]i »f Ok' klioiililtc. jTmtul.) 



part raises the elioulder, the middle draws the shoulder tiiward the spine, the 
lower pulls the scnnulu down- and inward, and tilts the arromion upward. All 
toother lift the slioulder and r>itnte (he lower angle of the scapula outward. 
jVerFw, (he c-pinul nccc^^ory, and the third and fourth cervical. 

Levator Scapulse (Figs. 2J*0, 286).—" Tin- Hftcr of the scapula." Sj/nonipn, 
levator angiiii snipnla-, "the liiVerof the aiisjle of (he scapula." Situation^ on the 
Hide of the neck from the verteUrtt tothenpiR-r Kcapuhirantile. Origin, the hind 



J 



RHOSfBOIDKCS MAJOR. 



260 



tiibercirs of tin- trnn.«vcr«' i)riK'<'<''i'* of iIk- ii]i|>it four or five wrvicul vrrU-bne. 
fiiivfiimt, ilown-. <>iil-, ;iiiii Ixii'kunri). inttrrliini, tl«' v»-rli'bral Ixinlcr "f \h.v 
scaputn frcmi tin- iijumt aw^U- l.i tin- rool of i1m> ^mne. At-Hon : il lifts thi* upper 
aa^Xv <<i x\w M-iipiiiii 1111(1 ih'jiruGMS th« tip of the shoulder. Servf», \\w Uiird, 
fotirtli, iumI finii <iTviral. 

Kbomboidtua Minor ( V\^. 28.*,, 287).—" Th« amalW rhomt^Hilmped iium-Ip." 
SittiUion, in tiii^ tjiwk, l>etwci;u th« npinal column and the Hcapula. Origin, tJiu 





Fin. 3«.—LuT>l<iTM«pulira< right •tdo, nar vUw : 
<ndun«ii(id *ltsphiiiclil-«i«w. iF, II. Q] 



no. m.-^RhOmbold^iiB vttncir bii<1 rhomboliteut 
malc^of risht >li1e: ontllDciiDr] sitxbaivnt-Bfia*. 



lllg ' 



lower part of tire nnpc ligament, tht> spin«« of tho t>evcDlh tii-rvicat and first 
thorai'ic verttbrw. JJimiii/n^ down- and oiilwanl. lutrriion, the vi-rU-bril Ijor- 
d«r of the scapula at iIm> root of !l8 spini'. AeHon : it dniw§ the i«cupula up- 
and inward, iiikI doim^iei the lip of tlic shoulder by nxaiing the scapula. Nrrvf, 
the fifth cervical. I'hirt niiisclu ii* often united with'th*- Ibllowin^ : 

Rhomboidftua Major (Fi^p.. 285, 287).— "The Inrp-r rhomb-fihai««l muffle." 
Silii'ilioii, in ihc l>a.k, Wtwi-cti tlio i^piiiiil cnhinin ami the scapula. firUfix, llic 
»pinou« pr»ci--*!i of the ujijmt f-.ur or five thoracic verlcbm- and the ei>rryv«[wud- 
iiig supnwpinouH ligament. Dirtctiott, down- and outward. luvertton, tJie vcr^ 



270 



THK MVSCLEfi. 



totral bonier of the scaptilu, betivcfii the- root of the spine ami the lower angle, 
jlrfiwi ; it draws the »(^upiil« uji- iiinl inwurtl. .Wre, tlit- fifth eriricnl. 

Serratus Magntui (Fij^. 2>tKJ, — "Tin- prciU siiw-tootherl miiR-ii-," Stfnonym, 
KTintii-' iirili-riyr. Silnalliiv, on the iijiikt Iwo-thinlif of the nde of the clMwt, 
Origin, by tlig^lations from Uie outer siirtiict! of the upper eight or nine ribs. 




Fm, SML— »«mtu« inuiiua of rifht ildc. Tho ifapuU Iim born tum«d backnard anil dntrn outwud. 
{Modinwl rrmn Tatut.l 

several inches from their front ends, Dii-ectioii, up- and haefcward. InaeiHon, 
tile front nf the vertebral border of the seapula, and the surl'aees at the upper 
niid lower angles. The fimt digitation. which conief from the seeonil, as well o» 
from the first rib, runs to the surface at the up])rr angle ; the w-oond tiiid thirtl 
di^itJitionH connect the eorrc*ipondiiig ribs with the vertebral bonier frotn near 
the upper to near the lower angle ; the re;^t of the slips converge to llic surface 
lit lln- li'wcr angle. Action : it dniw? the slioulder forward, a* in pushing ; tho 
hjwiT negnn-iit mlaU's the n\K-x of the Miiimlti upwanl. Xavf, the posterior 
thonicie. The lower five )>oints of origin interlock with umilur slips of the 
ohliquuH exteniu.t iibdomlniH. 

PectorallB Minor (Fig. 289, 21)0).— "The smaller brenst-muselo." Siluation, 
in tlie front of the chest. Origin, the outer siirfaoes of the third, fourtli, and fifth 
ribs, near their cartilages. Direction, up- and outwanl. Itmrrtion, the coracoid 
process of the scapula. Artion : it draws the t>boulder down- and forward. 
Tferve, the internal anterior thoradc. 




SUBCLA VIUS. "^^^^"^ 271 

Bubdavlns (Fig. 288). — "The mul»?r-thf-<:l»violc miwclc." Station, indi* 




Pm. 2W.-rM?lotaU* minor of rtahl ilit*. <Twtut.) 

cated by its name. Origin, (he first ril) naA it.* cartilage, at their jiinclion. Direc- 
tion, out- and upward. Itiaertioit, the grouve in llie under fturface of the flaviclc. 




Pro. IK— rvctnnlli lalnor at ilKlit ilitc - uulllne iind nluchmfMil-iiKU. If. S. U, > 



ieiion : it draws the shoulder down- and forward. J^Vrw, fmin (he fifth and 
sixth cervical. 




872 



THE MUSCLES. 



MUSCLES MOVING THE ARM. 



Abductors. 



Addaetom. 



Deltoidcwji. 
8iii)nti^l)iiiatU8. 



P<K^t(iralii' miiior. 1 , j 
*-• 1 1-1- -flwo m 

Comcii-brarhiiiliK. J •' 



'ejcore. 



Teres uajor. J 



■ aim cxiaiiort. 



Ouheard Rotator*. 



Iiifnu«pin«tti«. 
Tfri's ininur. 



Jnieard Rotator. 
Siiljscaiiularis, 



Till- larffp^t two of thene muscles arise mostly from the trunk, and in some 
jijiri IViiin flie f^Iiiiuldcr ; but the majority urist- wlinlly from the shoulder. All 
of them are in^crtc*! inio tin- himuTii^ in its uiiiitT linlf. 

Deltoideu* ( Fi)i^ 291, 2!»2, ;i09).— •• TIk- »U'ltu-lik<.- muscle "~" tieltn " bcinp 
the name of a Greek letter of (rinnjfiilar >lm)>)'. It is commonly Ang:Iieizvd into 
" deltoid." Sidmtiim, betwwn the mo« jmmiinont parljt of the ehuulder and the 




Fm. m.—Pront of oli«*tui(lihould«Tur rirl" ild«, ^up*'rflTl■l miudt*. {Tvitni.) 

middle of the out.-.!de of the arm. Origin, the front of the outer third of the / 
clavicle, the outer border of the acromion, and the lower border of ihe spine of "^ 



DELTOtHEVS. 



Ihr scapuln — c<irrv!*[K>mItng i-la^oly witli ihf insertion of the Irancziui?. 
frjin Uir i-Livifli- ami clio .-cai>ular s|>ino tlown- uwl outwaixl, irctni tli 



273 
DC acromion 




Pvx ?n— I>i>Iiolilnu or rigtit iIiIf. t1*«h] ftvm nbore: onRlno and attsehiaoiiCHirMiL (P. B. O.) 



fidvmwan]— all parts converging. Insertion, the deltoid eminence (or imprefisioa) 
i>f rhi- linnuTiij'. -Wion. ; it iibductif tlic arm, lifting it to (Ik- lioriwmtal. TIw 




Fill. ga. Biipr«ii[itniiiin •:! rii;!ii >!i1r, vl«vn1 tttim klMTa: oallina ami MU>ctiiii*nlHUvn. (V. R. 0.) 

claviciibir portion iicting nton« dmwx tli<> nrm fitrward; lluit (torn thv i^(»|>ii)ar 
spin» l>r ittfcif cnrrics tlie arm buvkwitrd. The unn, being niiiwd a» far uh tlic 




ffta. IM.— FciHonilla major of rlsht alilu: outlloa anil (tMirhmeDt-aiGai. (T. II. O.} 



tleltoid can afftct it, 'n^ elevated to the peri)eiiiii<iiliir hy tli« (rapoxttu, tJii- two 
mu»;le» bfiuj; almost continitotis in structure— pniotiejilly one mUDclc willi on 
oweons iui>cri|ition. JVpjtv, the circumflex. 
l» 



274 



THE MUSCLES. 



SopiuplBatiu (Fipf. 233, 298). — "Tin? »ui.-.clc «liovf the ^\Aw" of tli*^ scaiml 
t^iliutiion, ill tlio !<iiiin(s|iiiioii.'< fosHii and aliovt:- the lu-iid of llu- hmiifriiri. (irirjin 
tho inner tw<"i-tliir(iH of tlie stipraspiiiouji foKsi, DiiicHon, oiilwanl tioneaili the 
ai-mntion. Jtmeitiou, tite Hi))>i'riiKM>t facet of tht* greal tiibenitiitv of llie h<in]erui% 
Action, abdiicli'tii of the arm. .^Wre, the linpraneapular. 

Pectoralis Major (Figi*. 291, 2M). — "The greater brcast-nm-icle." Situalitm, 
in ihe nmwr. anterior part of the chest, and in front of the axilla. fJriffin, ihv 
>*tprnal half nf the anterior surface of the clavicle, the untcrior t^iiHiioc of IIk- 
Btcriinm {cx<^']>t ihe cti^iform process), the ciirltlageti of the iipjH-r six ril)». DirfO- 








Fill. £>TI,— ComcohnK-tilalla t>t 
riflitilitu^ iiiilllnv and ■lUi^liuirnt- 
■rou. If. 11. li.i 



Fio. 3M.—UuMlei In tbc niiictficiBl Ittjcr or nip back. ITiMtnt} 



k 



Hot : of the Havieiilur iHirlioii (whioli i* litepnnite iit It-* origin) down- ami outward ; 
wi' (liv eenlnil, oiitwnni ; of the lower, out- mid iipwnnl — all ]mv\^ eoiiverging to 
one broftd tendon, which twi*l« on iuelf, ihe lower tiling jnnt-sin^ behind and bt'eom- 
ing iipiHTmost. luMvlum, tlie external lipof tlu- biei]iital gro<»vc of the humcru);. 
Afiitm : it draws thi^ arm imvard and forward, and i-otales it inward. .Vcttct, th« 
uitenial anil exirriial .interior thoracic. 

OorocQ-brachiAlis ll'ifpi. 29'>, ;t03. 305). — "The conicoid [^process] arm iniKwh'" 
—the name being derived from tJii.> parts (H>iiiiccti'd. Silu<ition, in the inner side of 



TEHKS MIXOie. 



27d 



* 



ihv np|KT half of llic arm. Origin, the corao'iiil ((nx-ct^v of thf iM<n)i<iIii. lUrrrtimt, 
il<i«'iiwur<) iimlf-li^'htly oiitwsiix]. Insertion, llw inner t>orth'r of ilii- liiiiiionLiat the 
iii!ii<llc iif IIk- i-lmA. AdioH, »t\- 
(liiction ami Hoxiuti n( llic »nn. 

iVn-IV, the lll»IH.'ll]4>KTIltHtK-<IUI^. 

lAtiadmm (Fig». 'im, 297). 
— " 'n»e br«e<l*wl miiwU- " — t'n>m 
thp L^tii) fnfiiK, " bmitrl." Si/nrt- 
H^»i,l»ti^iimi:'<)oixi," tliv bnniil- 
e^t of (he haok." SitHalinn, iit 
the bark, fruni tl>e lower half of 
the spine to the upi>or iiart of die 
nrm. Om/iii, the .-ipines nf six 
iir w.'%fii lower thoraoic vorli-Iint', 
itn<l. ihroiiKh the IninUti' fii.-oiit, 
the !<i>itK-H of tho lumbar ajiit ^<u-- 
ral, tin- Iwiotc part of the outer lip 
iif ttH' iliar en-sl, tli« lust three or 
four ribs, und oAeti iho lower 
angle of the i^ciiniila. IHrrdion, 
upwani, ■iiilwanl. iiml foni-rtnl, 
iHtnvfiyiii;; to the ini<«nion, the 
lenihiii rwi^ting from above down- 
wartl and lniickvranl, w that itii 
front U Minliiinoitii with tliv biwk 
of the mu-ti'le. buurlinu, the 
floor of the bifipiiitl pnn)ve. vie- 
titn, a()du<;tion, exIeiiMnn, urn! 
ri>taiton inu-anl. Xm-r, the Iciiji 
siibi^npular. TIw <^(Kt|Hl ]M»rit.< 
of origin inter]o(;k witii iho^L- of 
the- ubliqiius exleraus al>doininis. 
T«reBMajor(Fi(rs. 298, 299).— 
"The greater rouiHlniuwle." Sif- 
iintian. between llie i-mpiila and 
the npjx'r ernl of the arm. in the 
tiinil wall of tiie armpit. Orir/in, 
the ovul siirfaee on the back of the 
«-iipnlu at il* l<)wer iin^rle. Dirrv- 
tlnn, up-, out-, anil forwanl. In- 

IHlfll 

iflllK't 

Kion, and in»'ard rotaliun of the 
arm, .Wiv, ihelowi-rsiiKMUpnlar. 

Inftaaplnatus ( Figs. 238, :t(K)). 
—" The muwle beh)W the spine" 
lit llie i«4^ii])nla. SilunfJoii. in the 
infnL-<pinoii* fo*'^ and hehiiiiJ the 
Iteiid iif (he hiimi-riL'r. Oriyin, 
!ho inner two'tliii^lx of the infra- 
si)in»n'< fo*sa, Dirfeihm, oul^tiinl. 
InnrrUon, the nkiihlle tivxt of tlic 
ftreat tiibeni^ily of tliv humerii>:. 
Arfimi, exienial rotnliott of the 
jirm. .V/rc, the .■>[ipn--<i-]ipidiir. 

Teres MioOT (Fi;p-. 29ft-;t(H).— "The sinnlW round nHi«:Ie." Sitwition, 
Iietwevn the scapula and the upper end of the arm, in the himi wall of the artn- 



la-rtliiit, the inner lipof the liieI|iilAl 
griMive. Acliiin, uttihK'tion, exteii- 




Vk.. 2W),-'L>tlwluili> of riRM rfdo: omUnu ami iitt«h- 



276 



THE MUSVLEH. 




FlO. 558,— MowlP« iif (he <lQBrim «f Ih# «c«Ii"l». rtiiht ilil*. (TMtuU 





Fin 'Sn.—Tttit luajnr of rJaht lids: Outline 
and iilliicbin«nlni«u, (P. II UO 



Km. 300.— tiif[iu>plDRnui of rlitht *14c: uutUao aod 
■lUchmcnt-uvu. (K, IL ti.| 





nu, m.— IVm mlaur »r right alilc : ouUInc and Pio. *)K-»ubM«nil*i1i of rli^tiMat outline >n<I 

■tbWbmcQMniu. if. IL (r j alMchineai«i«u. if. H. Q.) 



MVSCI.ES MOrrXf! the IfNO/.K FOliKARir. 



277 



prt. Origin, tin- diirMiiii of tlu- si;ti]iiilii, iiliiii^ iL* nxilliiiA' lionlcr. DirfCtioM, 
ti{>w'.-tri[| niiil oiilwani. fiuartiim, titc lowc"! fitinct im llii- givttt lulicniMily of the 
iiunii-rii>. ArtioH^ t^xUTna\ rotation of the liunieniK. A'Ti-f, \hv vJiviiiiiflc-x. 

Subscapularis (Figis. '2S2, 'isa). — " The mUM;I« uiidur tlio Hcajiiila " — ihoiigh it 
h lif ncutli tlic boue only wh«n the liocly is prone. i^itttiiiioH, in front of the scjipnla 
ajid i!ii' hwitl of the hiimcnis. Oriyin, the great^^r part of chc venter of ih*- .■•eapulA. 
I)irti-li<i», outward and tbrward. Itutrfiou, tite stnM tnherowitv of the hunieruK. 
Action, iDward rotation of the humerus. Nerrcg, the upper and tower aubscajmlar. 

MUSCLES MOVING THE WHOLE FOREARM. 

Bic«p^ flexor nubiti. Trioejis extensor cubiti. 

RracnialU. Ancooeua. 

Brae bio- radial i^. 

One of tbe<<e muHcles aritieA from the iieapula, one from the i^mpula nitd 
humerus, nod three from the humerus alone. All are inserted into the skeleton 
of the foreann. 





Fm. an.— Uiifrlv* aS ilir (n-.i>t ur the tisbt ihoaldttr 



Fiii. XiL— t>I«-|« (Icxor eiiblU iif rluht tidti: 
nulUiio ui<l ultiu'liiiiciilHtna*, (f, II. (•,• 



Keeps Ftoxor Cubiti (Figs. 303, 304).— "Th« two-hwidcd flexor of the fore- 



278 



THE itUSCLKS. 



Bnn." SUaitlion, in t\\c front of the iirni. Oriym, rho i^apula — the long head : 
the upper liortli-r of tin- glenoid fosBa ; the short licaii : the j-oraooid process. 
IHreetioii, the long head : over the caput htimeri, through the shouldcr-ioinl, in 
the hieipital groove, and down to the foi-cnnn ; the hliort head unites with the 
long about one-fourth way down the sirni. hii^i-iioii, the main tendon to the hind 
port of the bicipital tuberofily of the nuiiiis ; n seconilury teudou (ealled also the 
ecmihintir or biejpilal fancia) paiwoK obliijiioly inwiinl, und endw in tJic deep Ihscia 
of the foresmn over the pn>natur toren. Affion, flexion of the fori'iirm. If the 
hand is prc.nalott. the biceps su|iiiiiittTs it. The wcond temlou of in><ertion tightens 
the foreiirni-fuKeiii- Si'rvr, the museiil"-<nitiineiiii,i. Tlie i«vuovial ineiid^miie of 
the slioiililer-joini is jirolonged downward, nnd invent.-* the tendon of llie lon^ 
head. 

Brachialla (Fig*. 305, 306). — "Tie raiiscle of the arm." .SyrMMiyiiut, linichiiili* 
anterior, braehialis aiiticiis, " the front raiiscle of the arm." l^lutdhn, in the front 





Pni. UA.— Mi»<-I» i<t Uiu rljtbt ana. rrani View, 
ttie bloe|» hartriB Iwvii tbidiitihI. iTuilul.) 



Fic. 8M.-Iln>rbUUt of ilthi 
•ildn: ouUlrio uifl muehinpni- 
anuu. (P. II (t.) 



nf thfiarm. Ociyiri, thehiwerludf of thecxtornni iind intenmlpurfiicvsMid ventral 
border of llie hunieni!^. Dindimi, downwnnl to the fbroftnn. Jn^nHon, the inner 



TRICKPS EXTEXSOn VVBITI. 



270 



gutrt uf (hv (.'onniaii) proc«?s«' of the tilnit. vidton, flesion of the foreunn. Serves, 
t)iv luibvulti-culiinvoii'' »tiil iKli^titly) till- mu^iilo-spiral, 

Braehto-«di*UB (Kip'. 30", 3(18, 323).— "TIk- iimi-nwliu* muBcle," from iU 
H(tu('hiiii-iit>. Sifiiiiiijfiit, ■>iipiiiH((>r li>ii|;ii>', ''tin- lonp Hiipinatnr." Situittinn, the 
otiit^r iiiid I'ntiit [Kirt of tin- ImviT fimrlli of 1Ih> :iriii iiikI uf t\u- whole foniinii. 
Orighi, th« upjwr two-tliinU of the ('xu-rnal Aiipniooncivliir ridgv of iJn' ItiuiR-nH. 




tvt. m.-Bnc)iio-n»li>ii* 
of rtrti »id». oowidc view : 

ouUiDHnnil lUliuliiiionl-arcM. 
<F H,<S,i 



FN. BRiT-duimflvIil mnulM of troal at right 

Jfirevllon, downwtinl, Jnacrtion, tlie biise uf tlio stj'loid process of tttc radius, 
Aeti/m, mostly Hcxioii of the foR-arm ; but, wIr-u tht- hamt is prone, this ihiimIi- 
is capal>k- of tK-]ir1y hulf-siipitintiii;; it; iiDer strong supination, thv musele will 
partiallv viTvai proniitioii. S'rrer, tlie mnp*cnl(>-«»iml. 

Tricipa Eit«nior CubUi (Fi(i«. 309, 311).— "The thrf«-h«>dc(I extensor <if lln- 
forenrm." >S(7«rt/iV>»i, in ihe haek of llie arm. Origin, thv lon{^ (miihlU-) liiwi : 
below tlie glenoid fov*a of the »capiilu on lh<; nwk mid np]>er piirt of tin; nxillary 
border; tin- <-\li'ni:il hiwl : the hin<] nnrliti'*; of the huiiKtniH niiove the miiiM-ul(H 
spinil groove; the inU-nmi (dtvp) tiejid : the hind Hirfiuir of the hnmeni.s below 
tlie muiwulo-iipititl groove. J}b'ectiony downward, all Ihe heads uniting in a com- 



270 



THE MCSCLES. 



trbral bonlor of (ho scapula, Iielweeii the mot of the spino nntj tlic lower angle. 
Aftion : it draws tli«^ Bfapula uj>- and inward. .Vwrc, iln- fifth i^orvioiil. 

8erTa.tQ8 M&gntis (Fig. 28»). — "The great saw-looilicd miiscU-," .S'ynonym, 
sermtii!^ smteriin-. f^ihtifdon, on tlu' iipi>er iwo-thinU >ii' thi' .Hide of lliv ohcst. 
Origin, by digitations from tlie outer surface of the upper eight or nine ribe, 




Pto. 3W. t't rimlm mwnoi of rlcht ddo. Itiu icapuU ha* b«cn tamed bickmrd koA disvii nuMard. 
modlflcd ftnm Taint.) 

iwvi-rnl inolw'^ tViHO thvir ftoDt «nd*. Dirrftinn. up- and hackwiird. JuKi^ion, 
the fnnit nf tlic vcrtclmil Iwrdcr of IIk- rK'ii])iilii, mid rhi- siirftn'c" nt tlu- uppr 
and lower iingli^. The first digitatiun, which oome.'* from lh« wwtnd, an well as 
from the first rib, niii.-* to tin- .xiirfaoi- nl the iip|WT nngh- ; the wonnd nnd thiixl 
tligitation.t conmrt the eorre^jmnding rilis with tIic verlobrnl border from near 
the npTMT to near the lower angle ; the re.-it of (he slips eonvergc to thf -urface 
ut the lower angle. Action: it draws the shoulder forward, as m pu.'^hing; the 
lower Bcgment rotates the apex of the seapula upward, 2\'ci-fc, the posterior 
ihonicio. The lower five points of origin interlock with similar slips of the 
oblitpuis exteniiis abdominis. 

Pectcralis Minor (Fig. 289, 290).— "The smaller brcaat-muBcle." Situation, 
ill (he front of l)n- chest. Orit/lji, the outer wurfnces of the thml, fourth, and fiftli 
riliK, iidir their eiirtiluges, Dirtvthfi, u])- nnd otitwiird. Lisfiiion, the cora(.i»id 
procefiB of the scjipula. Aflioii : it dniwii the shoulder down- and forward. 
A'erre, the internal anterior thoracic. 



SUBCtA VWS. ^^^^^ 271 

SabdsTlas (Fig. 289), — "The iiiulcr-tlK--«Iiiviclcr muscle." Situation, indi- 




Fi0.nfi— FtctormUi mlnar i>f riKhi(Mc. (Tolut) 



cafecl by its nanip. Orifftn, the first rib and its »inilii|^>, M (heir jiinction. 7)iV«> 
tion, out- and upward. Irtserliun, the grtww in llu* under Mirtmv of the daviole. 




FW.SII— nKtur*li*iiiliioro/ riuliltldc: millliir mxliiIUDliinuiit-MViu (P. H.Q.I 



./IcifMiN: it drnwft the shoulder down- aud forward. Aisriw, from the &ilh and 
sixth oerWcal. 



273 



THE MUSCLES. 



MUSCLES 



r>f!toi(leii=. 



MOVING THE AEM. 

Addudom. 

PectopalU maior. 1 , ^ 
Con.co-bmcl.falis./"''"'-'^''^ 
Lalb^imus. 
Ten.* major. 



4 



n&o extentora. 



Onlteard RoUiton. 



I iifmspinatiis. 
Teres minur. 



Inward Rotator. 
SiiI>K^iipuluriK. 



Tlic Ifir^i-^ two of th«:te iniiiwlcit nriite m<>!<tly from \)\k tnitUc, and in some 
part from tin- .-Jiniildf^r ; but the majority iiri.-tf wlmlly from the shoulder. All 
of thcin nn- iiiHcru^l into the humeruH in U.'> iiiiiitT htilf. 

Deltoidetis (Figs. 291. 292, 309).— "Tiie th-lt.i-likc nniwlo"— "iloitu " Ixing 
the HMiiie i>f a Grwk leltt-r of triangular shaiw. It is crminioiily AogliciwHl into 
" (l«ltoiil." Situation, betwwn ihe most prominent parttt of the fehnukUT and the 




Fn.91.— Fronlof CfaMl>iid*lioul<1oruf rltcbtildc.niperflcUliDUiclok. (T«*nil.i 

middl? of the outside of thv urui. Oi-iyiv, the front of iho outer third of thej 
claviclf, the outer border of the ael^>^lil>ll, and tlie lower border of the !«pine of '^ 



DELTOIDEVS. 



278 



tht! (scapula — (■orm'iMiwIiti^ flii-aly with tin- iiiM-rlion *if llir- tnipi'Kms. DinvHon, 
fn>ni tlH- plnvu-lc iuhI ifiu rH^piiIitr s|)in<! ilnwu- »ud iiutwitrtl, lh>iii Uie acromion 




ri:. m-OcitaUtva or HgM cMe, Tl«irel(!mn abon: eatHiM m4 aiUulunuiMiM*. [r. !!■ O) 



il(»wijwiinl — alt parts convprg^nfi;. Jwietiion, the (Icltoid emincDCC (or imprwaion) 
iif thi- humcriiH. Aftion : it ahducis the arm. lifting it to the horizoiilal. The 




Tm, 3BI.— fiupruplnalnt ff ritti liilf. rlFwd from above: outline mi'I •tUcbmcnt-ama. (f. B.O.) 

clavicular portion acting slone draws the arm forward ; tliat from the ecapiilar 
spiiM> by itself carriett the arm hackwaixl. The onn, InHd); nuflct) act &r aa the 




Pia. ISt.-Prptomuinalocof rlffht ildc: tmtlliie aoil Utacbncnt-trcu. (7. H.OJ 



(Mtnid oan affect it, is cl('vatc<l to the ptrpomlii-iilar hy IIk- tnipcziiis, the two 
miiBclen being alnioat coiitinuoiia in hiructiire — practically one muscle with un 
oeaeoiiri iuHcnption. Nerre, the cimimHex. 

IS 



274 



THE Mf-ffCLKS. 



Supraspliutttui (Tifp. 293, 29S). — ■'Tint nmsi'lf tilmvc tlu- !«|Miic"of llie»«aimlii. 
Silmitiini, in lli>- ^titirjiMnnniiri fo.-«i luul almvc ihc luiul "f tlio Immt-mn. Oriffin, 
tlic iiiiHT two-iiiinlK i)f ilifi -.iJitiasiiinoiin (<.."wt. IHr'-riiou, iKKwartl licnoatli iIm^ 
acniiiiiiiii. IniciUon, ihf ii]i|K-rnio.Ht tawt of tin- ^if-iit tiibirnr'itv "*' tlie liunioruct. 
A'-liiiii, aMumi'ii) nf the ann. Nerve, the siipiii sea pillar. 

Pectoralia M^or (Kig^. 2ai, 21)4).—" The greater hn-awt-nniBcle." tiihud'ton, 
in Ibe iil)|>ei-. anterior part of the ehest, antl in front of the axilla. Origin, the 
stenml lialf of the anterior surface of the clavicle, tlie anterior surface of llio 
sternum (exoepl ihe ei)i>ifonu process), the cartilage:^ of the upiwr «ix ribs. Dira^ 




■JUT CIUVI 
CMi VCDTiaiM 



Vta. »fc— Corapo-liroeliloUi of 
ttlbl fliln : eullliiii miil *tt<irliiuciiit- 



Fn. 296.—Mu«cIm tn tbc £Up«lflcUI \*.Jtt nt the iMCk. 



4 




lion : of thi-elitvienliir iK>rtion fwliich 18 MiMinite «t its origiti) il.>wn- niwl outward ; 
of tlio ei-ntnil, niitwitril ; of tin- lovrer, out- mid npvmnl — all [wirts eonvei^ng to 
one brood lemioti, wliieh twi."!* on ilwH', the lower filircs juuisiii^ behind ami oceom- 
ing uppermost. Jtuvrtlim, the exlenuil lip of ibe bieipital jrnKive of the humerus. 
.-lr//Vni .- it tlraws the arm inward an<l forward, an<l rotat*-;* it inward. XeiTrg, the 
inteniiil ami •xHTiml anterior thoracie, 

Coraco-brachialls (Kits, 21IS, '-iO'd, 305). — "The coraeoid [process] arm miiselo" 
— the najne being derived from the part* cunnected, 8itttaiion, id the inner side of 



TEltnS MJXOR, 



273 



ponn'i»i(i [ii-wess of till- Hr.i|>iilii. I Hrrclioa, 
Intffiion, tla- inner bonier of ilii- liiituenu at lh« 



llie npixr half of tin- iirin. Oritfin, thf 
iloniiwanl itixl ^lijiflitlv outward, 
middle of t!ie uliaJV. Aetion, m\- 
duction and flexion of the arm. 
yetTf, (lie luuik-iilo-ctitancoas. 

LBtiMiiBUs (FiR^. 2d6, 297). 
*— " The bruadf?:! ninsrlc"— from 
tlic I^iitin l/iliiM, " Urociff." Sifiiit. 
nyin. lati'winiiii'ilorsi, " (In- brmul- 
ff<t of llu- liiiok." Siliiiitinn. in 
the tniok, from tlio lower luilf of 
the ^|>ino to tito iipficr |ictri of iiw 
arni. Origin, llio )'|)iiii-7< of fix 
or seven lower tltonteii' vi'i'd-bni*, 
and, thmngli the ttimliitr fiiHoia, 
tlip spiuts of tlie liimhar and ku^ 
ml, tne back part of the omer lip 
oC the iliac crest, the last three or 
foiir ribs, and often the lower 
angle of the seaptila, Dirfi-fiim, 
upward, outward, and forwanl, 
(■tmverginn to the insertion, tlie 
tciidou Iwistiue from above down- 
ward u»d bacKward, bo that ite 
front if continnotiK with the hack 
of the rnncric. /wwiViwi, the 
floor of the hiriptlid jn'"<'^'('- Ac- 
li/ni, ink I net ion, cxti-n^ion, iind 
Diialion inwanl. -;Vfr(v, the long 
MiibKcjipnlnr. Thr ooHttil [)oint^ 
of oripiii itiii-HiK'k with ihwc of 
the <>lilii|tiii!< ■■xli'rnii.i nbik'iiitiiU. 

Tetas MRior ( V\^i>. tiOH, 2ii9)-— 
"Tin-(rrt-itt^'rnnuid niiisi-h-." -S'i'f- 
itation, U'twii-ti the [*i:a[iiila and 
the upixT end of the arm, in the 
hind wall of the armpit. Oi-h/iu, 
Iht? oval snrfat-e on the back of tiie 
tTi?apiila at its lower an);le. IHivi"- 
tioHf up-, out-, and forward, hi- 
wrftwifthe inntT lip of tlw bicipital 
proove. Arliim, atldnction, exlcti- 
i>ioi), and inwunl rotation of tbi- 
iirm. .ViTrr, llirlowrri^iiliuR'apnlar. 

Infruplnatiu (Ki^rH. 2»8, litiO). 
— " The ninp-cU* Im'Iow the spine" 
of the iteapiihi. SUiuitiou, in the 
infra.-^pinoiiri fo^^^ and behind the 
head of the humerihi. Oi-it/in, 
the inner twtf-lhiifls of the infra- 
ispiiion'j fossa. Dirrriion, outward. 
imrriitm, the middle facet of tlie 
srrpat I II ix- rosily of the humerus. 
Action, fxlcrniil rotalion of the 
anu. .\Vv>v, ihe -iipit'-'-iipular. 

Teres Minor (V\\i^. 2iw-;)i.»1).— "Tli« MnulitT round nnwrle." SiiutiHtm, 
l>ptw<>en tho jtcapulii mid liu- up]>vr vtid of the nmi, in tlie hind wall of the arm- 




Piii. 3117.— IMialinu* of rljdit aide: outline ukJ aUach- 



276 



THE MUSCLES. 




Tm. ;^ — Mu9<>U'F of the duretim of cbeaearuli.rlebl iMr. (TvatuI ) 





Pin. an,— TcRv mMor of rtebt »ld«: outlluc Kio. 3>).— InrnupUmttu of nifat ildv; uuUlnv biuI 

■nil ■tUnhiDi'nt-ftrciU. (P. H. (U atliLCliniEiil-itrcit*. (F. H. G.) 





\ alUchi 



Pju. an.-Turw iniuur of rlslit »1<1B; uutliii* anil P)a, »^-«nb««PDlBrl*orrlaht«lde: (latttnc «n4 

•lUchmont-arvu (F, II, 0.) kitu-tiiiiuntiimii [P, H n,i 



Ml^-CLES MO VrXfl rilK WHOLE FOUEA liM- 



jtit. Ori'jiii, lilt- (l<in<iim of l)i(- sthjuiIh, iiloii^; its nxilliir}' IhiiiIit. Dirr^wm, 
u]>uaril nii<l oiilwanl. luMeitiwt, tlir IntvoHt (i\n-X on tin- ^iviti iiilHTiii>ity of tlio 
huni('rii.-<. Actum, cxtcriial rolation dI' tlu- liiiniE!ni!<. Serrr, llic i-irc-iiiiiflcx. 

Subscapolaxis (Figs. 282, 'lA:i). — " The niuholo uml<;r tho .^cuptilit " — tlioti);li it 
isbeDOJitli the bone only when the boclyis prone, ^utilhit, in front of (he .'^onpnla 
and th«? head of the humeruH. OW(7in,thegreaterpart of the venter of (lie smikula. 
Uirevtion, outU'srd iind forwanl. Ii*»rrthh, the small tuberositv of tlie buinerui<. 
Actimt, inward rotatiun of thv humerus. AVpm, the upper and lower subscapalar. 

MUSCLES MOVINQ THE WHOLE FOREARM. 



TricejKi extensor cubiti. 
Anconeus. 



J-'itxorti, 
Itkep flexor cubiti. 
Braehialifi, 
Hrachio-radialis. 

One of these mti»<eles arii^es from the wjtpula, one from the Boapula iind 
faumeruii, an<l three from tlic humerus alone. .Ml are inHcrted into tlie skeleton 
of the fon-urm. 





Fill. Ml.— Miiwin uf Ihvi Irani uf Uii- rltifal ihoiild«i 
an-l «no. iTiuiiil.i 



Flu. 301.— Bleep* ttexot mblil at tifMM*: 
oulllue ■nil HIlai-IiiiiviilHiruiu. if. II. U.t 

Biceps Flexor Cubiti (Figs. 303, 30-1).—" The two-headed flexor of the fore- 



278 



THE MUSCLES. 



arm," Situafion, in the front of thciirni. Origin, tho Acapnia — the long head: 
the upper bonier of the plt-noid fVnwit ; th<- short hcjid : tlii' forncoid process. 
tHrce/ion, the; long hctnl : over the aipiil lninnTi. tlimiijih thi.- slionlik-r-joint, in 
the bieipital groove, ninl down In t\u- tiiri'iinii ; On- nhorl hcml nniUs wJlli the 
lonj^ nbont ono-lonrth wiiv down ihc arm. Iiiiwrliiiii , the main lendoii Ui the hind 
part of [he bii^ipitiil liilx'roKtly of (ho nuliiM ; n sceiiiuhtrv ti'iuloii (mlU^I iiImi the 
Sfmilniiiir nr liiiipiiul fii^i-iii) jMsses obliqui^ly inwnrd, anil omU In i1h> ilcep f]iM;iu 
of thp forearm ovc'r tht' pronaUir toren. Aftion, flexion of the furx-jirra. If th« 
hand l-^ pmnateil, the hiooits Hiipinate» it. The Jteoond tendon of im^c-rtioii tighU-if 
the forearm- fawcia. ,\Vriv, the niUHcido-eutaneoii»<. The synovial nienihram' of 
the shoulder-joint I* prolonged downward, and invests the tendon of tho h>ng 
heikd. 

Brachiklis (Fi(fs. 305, 306).—" The muj^le of the arm." .s>h(mii/wm, bracWalis 
anterior, brachialis anticus, "llw.- front niu«ck- of the ami." iSi(H<i/(wii, in the front 





Pin. nV— Muielcs -it the rlslil >rtfi. fitnit vl«w, 
Uiv blr»|is hai Inx iwcn Tvinorcd. (Tuatui-) 



riu. »a.-llnu'hlan* <■( TiBht 
■Idci oullino and iiiiachincpl- 
•IHU. (F. H.O.) 



of thearnt. OWi/iii, lh# lower lialf of the external and internal aiirfaeeswid venlml 
bonier of llie hnnifinis. Dircctmn, downwanl to the forearm. Insertion, the inner 



TBWKPH EXTESSOU PUBITI. 



jKirt of the coronoid pr(»e<>** of ilic iilnii. Ad'um, flexion of the foniirm. Srrven, 
the n)i»eulo-i-iitaneotLH am) (,->lifrliilv) tlu> niiuciilo^pinil. 

Br«*io-radlaU8 (Fijp. at)", 3(18, 32.1).— "Tin- iinii-nwliii* miiwle," fmni \U 
allaoliment^. Nvitonym, I'liiHiialor Ii>iipM-<, " ihc linif; »ii[)in:itiir." SUtuttimi, tho 
nuier and front part of the Kiwpr fourth <if the arm aiwl of ihi- whole foii'iirm. 
Origin, ihf upj»cr two-thirdi* of the external Hiipraootidylar ridge of tin* liimienis. 




Tvi- Sr.— Uraehlo-nulialti 
of right il4c onulilc (trw; 
MUIdcuiiI anacbnicnt-ucM. 
(F. H.O.J 



Vte W^^uinrflcinl miiicira of tnnx at right 
bnwtD. (Ttttai.) 

Direetion, downward. Jnnn-tinn, ihu biisi; of tlic ntyloMi proccjo* of th« nuliui*. 
Artion, m<Ml]v Hcximi of tiic fon-urni ; bill, whi.-n tlii> hnuil if prone, this niiiM-li' 
is ea{>ahlc of ntsirly hulf'-^iipirKitin^ it; after nlnfiig Hiijiination, the niiiM-le will 
[>arti3lly effi-rt |iroiialic>ii, .\V/rr, tite niuMuhi-npiral. 

Triceps Extensor Ouhltl (V'\^>. :i()'J, 311). — "The thriHr-hcaiWl cxlensor of tl»c 
forejirni." SUuntiou, in the Imek of the nnn. Origin, die long (middle) hea<l : 
behiw the glenoid fo.-^'ta of the Hcapida on the neck and np{>er jwrt of the axillary 
border ; tlw" exttTnal heail ; ihe hind surface of the' humerus ahove the mii^'uto- 
spintl groove ; the inK-rnal (deep) h«id ; the hind eurface of tile hnnieru^ below 
tile tnusculo-epiral groove. Dirtctwn, downu-ani, all the heads utiitiug in u com- 



280 



THE JtrSCLEff. 



mon tciKion. Insertion, Uie back of the iiiiikt part nf ihe oWnnoii proceae of ( 
iiltKi ami. l»y il few fibres, the jioatorior liganieiit of the rlbow-joint. This Mnall 
jMtrl. i» Hijiuc limes ealletl the nubanconcua muadt: Adivii, cxtciUMon of fbrmroi. 
.Vfnv, llm miinnilo-spinil. 

Anconeus ( Kip*. 309, 31 2, 330).—" The olbow mueelo." Sitnativn, at tlw back 
iiml oilier !<iik; i>i' tlu: (.'Ibow-joinl, mostly in iht- furi'ariu. Origin, l\w liiii<l i«rt 







-^nti^tt^UiucIn ontbvdoreiini of th« rlfhtihiHililviuiil iiriii. 




Fi>i. aia.— TriocTo cxwunor tubltl of 
rluhiilcli'- i*n ortli«iP>puUthc>id ha* 



of the external eondylf "f tlie hiiiniTtL«. fftrceHon, obliqwiy ilowiiwjinl. IitKo-- 
iJHn. ihit oiitwr wide of th(! nWninoii prooess, and iht- iipiicr futirth of tlu- donwl 
tinrliiof of tlir !*Iiiifll <if thti iilim. .iciimi, cxtviwion of tlif fiiriarrn. AW-rr, the 

Imii»ciiln-^plni1. The nnoani'iii* in a ooiiti mint ion of thi- triotMH, ant) 'irt nompiiinc?< 
dewi'i-ibiHl as tho fourth head of the lalK-r, thns nonvertiug it into a cjiiadrioeps, or 
foiir-lieaile<l niuticle. 



UD80L£S MOVma THE OUTER PART OF THE FOREARM. 

l*rim<itnrM. Siijilniilor. 

Pronator t«nK Kiipiniilor. 

Pronator i|ua(Initii.'<. 

Of the pronators, ou« arJBCs from the hiimerua iiiui uliui, the other from the ulna 



JPJtOXA'irm QVADRATVS. 



2«l 



imly. TlMM-npinatur ari^t'S from x\w liiini(rrii>' mid Itii- iilTia, All !«n- itiMri.il into 
tliv niiliii);, wliirli ;il<inc<>r tlic foriiirui bnin.'i i* nuivri) in [in •mil ion iiiiil Hii[>iii'.tlti>i). 
pTDaator Teres (Figsi. 307, SI.'J). — "Tin- n'tiinl iniiiiatur.*' SUualiou, in tlip 
front of iIk- forx-jirMi. Origin, tin- giiiwrBviiit liaui : ihc iniu-r omdylf of the 
)iunK-ni.-< niMl a ^ma\\ |>art of the ntlgc iiIkjvu it; the dotrp-hrail : xhv inner 
Ixii-ili-r of llip wironoid |>rocc-»H of thv iilim. lUredioit, out- ami downwaitl. 
iHxerdiin, iho niiddlc of llw outer imrliua: of the radiui;. Avliini, |iroimliij» 





Pw £11.— tHmik «ii«nior puMtl of lintit aldf : oni- 
linp bikI nllubiiM^t-arTBt. {T. M. <>.) 



Fli>.SI3.—AneonMU or light tldr: nutUn* 
and iutiH4)m«nl4niM. IP. H. Q.) 



of the hai»l by moving the rndiui' to whirli the hand ic nrtioulutvil ; aim sliftbt 
fl<>xtoi) of (hi' for^ami, .Vit«-c, tho nicHliun. 

Pronator Quadratna (V\^. 'Al-i, :t38). — " The scjimn; pnHiutor." SlfHaHon, iu 
tbo lowiT ijiiiirt^T of the front of tiie forc.irni, dose to tho buncit. Orujin, the 




THK MUSCLES. 



J 



jwer fourth of the front surface of the shaft of the iihiil. 
InafrtUm, the lower fourth of the front of the radium. Aeiitin, 
dius, ami, eonpefiiteutly, of the hand. j\mv, the autcrior 
[>f the median. 



f- 





Fli>. 31S.— PronaloT ten's, right tide: outline 
•nd ut[acliment-an:Ba. (F. H. G.) 



Fig. 114.— PronittoT quHdraluR of lijrlil BLde : 
ouU1d« And atUtchmvnt-Brcuii. tP. H. U.) 



Supinator (Fig. 305). — "The supinator." ^ynimym, supinator brevis, "the 
short supinator." Situation, deep in the tipper third of the outer part of the 
forearm, Oz-ii^m, the back and lower part of the external condyle of the humenis, 
the external lateral and orbicular ligaments, the triangular area l)elow the .smalt 
sigmoid cavity. Direction, out- and downward, wrai)ping the iipjier part of the 
radius in a sling. Innertion, the back of the neck, ana the hind and outer surfaces 
of tiic shaft of the radius above the oblique line. Action, supination. Nerve, the 
posterior interosseous division of the musculo-spiral. 



MUSCLES MOVtXG THE WHOLE HA Xli. 



SS3 



CO HOI LI 



OtXCB*' 




na sis.-euiiiiutui ot right vide. 



(Tntuc) 



MUSCLES UOVINO THE WHOLE HAND. 

t'Ujnir*. }-lxiru»"i-K. 

Plexor carpi radialis. Kxtensor carpi nu]iuli;< tongti^. 

[Kk-xiir] [lalinans lougii». ExU-n-^ur osriM ni<litilii« bn-vis. 

Flexor <:;ir|)i iiliiaris. Kxk'tiMir uirjii iiliiiins. 

All nrJM.' rmm the hunioni», nnd tho flexor and extensor on ihe uliinr side 
' 4xmi<- from tbo ulna alM>. Th« palmarii^ lonieuK is inserted into tJie palmar fa-soia. 
All whii-li havp "carpi" in their namt-s are in- 
fti'riM into mctocurpal bones, ami only one of them 
into any pan oi the oarpiis also. Their uction, 
however, is correctly indicated by their nanK«, 
the nfisi. carrying the rest of the Imnd, boine 
altematelv flexed and extended. Thi' Kitwnd, 
third, and fimrth nK-taciiriwd Iwrif'* hiivi' pmc- 
ttcally no motion on the cirpiis, and llic (irst and 
fifth arc movitl by s)><ftiil miwcW. The pal- 
maris longtu*. tliuiif^h primarily a tensor of the 
palmar fa^ciii, '•eoondiirily is a flexor of the hand 
— jnst iw till* lensor vaj;inie fenioris la firsi a 
lightcmT of lb*- fascia Iain, and then an abdiie- 
tor of the thigh — ami, therefort', a bracketed 
word implying this, and aiding the groiipinj; by 
making a uniformity of name which eorreepontti 
with the practical idendly of action, liiw been 
prefixed. The adduction of the hand is acvom- 
plii^bed by the siniultaneuu<' action of thu flvxor 
carpi ulnaris and the extensor ciirpi uliiartD ; itit abduction by the ^imultaneoiifi 
action of the dexor carpi nvdi;dis und the extensor earpi radialis longitw. Observe 
that the rjrternal ]Kirt of thi- tower end of (he hnnieni!! gives origin to the o^en- 
sor^, the internal to the flexors. At their origin from the internid condyle and 
its ueigbborhoiMl th« flexors of the hnnd arc so blended with the pninntur teres 
I and tlK- flexor «ubliniii< digitoriim as to eouHtttuto oiiu maw. On tind id)out the 
Eternal condyle i- ;i r>ttnilar aKtOciatioii of cxlcnsont and supinator. 
Tlexor Oaipl a»dlalis | h'igs. ^ilti, :tl7).-^'-Tlic fli-xor of ibe wrist on the 
radini side." SUiuiUon, in the front of the fort-arm. (irli/ui, thf iiun-r coiKlylc 
of the hunn-riLs. Dimriion, downward and a liitit- outward, liutfiliuu, tin- iiase 
(if Uiij si'ooml metacarpal Iwnft on its palmar aspect. Artion, flexion and sliglit 
pronation of tht? hand. In oonjunclion with the extensor carpi ladialis longus it 
\ abducts the hand. Xervif, th<> median. 

[Flexor] Palmaris LonKOSlFig. SIB), — "The long palmar [flixor] muscle." 
SiUuiiioH, in ihc fi»nt of the fon'arm. Orifftn, the inner condyle of the humerus. 
Direction, downward and hlii.'htli' outward, fnxcrtion, the palmar fa-rcia and 
iiritcrior annular ligament. Artion : it tightens the fascia of the pulm, and tben 
tl'-xe« Ihe liand. Nerve, the median. 

Flexor Carpi Ulnarte (Figs. 3lli. ;118. 380).— "The flexor of the wrist on the 
tiinar t^ide." Sltn'iliou, in the front ami inner bonier of the foponrni. Orltfin, 
one head : the inner (■orulyle of the hirmcnis ; ihi' olher head : the inner side of 
the olci'riuiou and the itpiier two-tlncils oi' the ihirsiil border of the ulna. Ttw 
origin fnmi ihcihii'sal bonli'i' of I lie ulna is bv n tuudnii conininn lo liiis muaclcand 
tlie (.■xitn^iir earjM uliiaris and the Hcxor profundus digitorum, Jfirrrtiun, down- 
ward. /»MrHj(>(i, the pisifonn, unciform, and the base of ihefift}) metacarpal. Artion, 
flexion of the liftn<]. In conjunctioit with the extensor (;Hr|)i nlnam it ndduets 
the baml. ,\mv, the ulnar. 

ExtOMor Carpi Radialis Lonjna {Figs, :!1 9, ^20). — " Tlie long extensor of the 
wrint on the radial -idc." Situation, in the outer Imrder of the forearm. Origin, 
the lower third of the external anpraeondylar ridge of the humerus. Dim>- 



284 



THE JIISCLES. 



timi, Jownward and a little bai-kwarcl. Iittertton, tJie base of the wpaH 
nuIacariKil, iM'huui ami nn th<- latlial jiUIe. Adton, extcn(>ion of die Itniid. 
Ill conjuiipiioii with the tiexor carpi mdialie it abducta the baud. AVrw, the 
miiHculo-tipiral. 




Fid. lilt,— Snivrnrtsl mmclM 
«r trtiM of ilghi fonann. 
(TMtUt.) 



of tight ddo: uuttin? itnil ■tuirh- 
nwbt^reu. <F. H. 0.) 



Pio. SU.— Fliixnr »r)>l uliinrll 
or rlkbt «!<]•: oultlnp and altarh- 
in«llVU«u. ir. IL 0.) 



Extensor C*rpl RadljdUBrevis I Fip*. .'ilft-.121).— "The short extensor of the 
wrUit on the radial side." Situiilion, the outer border of the forearm. Origin, 
tlie outer condyle of the hiimeruft. Diredwn, doirnM'ard and a little l)a<'fcwurtl. 
Insertion, the W^e of the tJiird metacarpal hone, behind and on the milial if'ule. 
Arfion, extension of the hand. jVwrc, the jHJslcrior interuKsciie bniiii-h of ihc 
muse uio-»pi nil. 

Extoiwor Caipi ClnarU (Fin*, 322, XM),—" The c-xtensor of the wrixt on the 
hlnar side." SUuation, the buck uf thv forearni on thv ulaiir ^lide. Oriffin, the 



jiXTKXson CAJii'j ii.yABis. 



285 



Fm. tU^-UmclM la ndlal ngloa oT ttcht bnarm, and dctp mucloi La Hi dtmuii. CTmiiii.} 



2S6 



THK XVSVLES. 



cxttTiiiiI mmlvle of the hiimoru-t and Iho miiMIc ttiinl of tlic dnrwiil border ofilic 
iilim l>y tlit^ tendon fiommoii to ii, tin- uliiflr tiexor, and tlu' dfiji Hexor of ihc 
fiiip«T!«. i>HTrfiott, (lownn-ard and inward. I/iM-rtion, the base of the fifth mcta- 



InnKiia of rlglit lid*; oiitlliiv Bnil ftt 
lacliuicnt-ariiM, |F. Q. ti.| 



Pia. Kn.— ExUiuor rArpi ndl- 

*lla bniititiir riuhtnlila : uiiUInu 

od|- ■ ■ 




•ad M(arhnitMil-«i*>u, IV.II. it.) iarm*tfM. IF. U U.) 



Pill, m,— Ritriwur ritriil uliuuii 
ot rloht Bid* : uuiliim aii'l atUcfc* 



rarpal bono on its dorsal aspert and tdnar border. Aetion, est^tiaion of the hand. 
In ronjiiiifliori with the flexor nirjti nhiaris it uddiicte the hand. Xtrrf, the 
piMtcrior interwiH'ons branch of the luusniloapinil. 

MtJSOLES MOVING THE FINGERS 
and the Fifth Metacarpal Bone. 

iTliOM whicb att uttuttHi (iitlriJ.v iii Ui« tiatiJ ar« lii(l!(;til«il \i;f a 8IU.) 



Flaora. 



Extfnaort. 



Flexor i^ublimiK digitomm. E-tlensor communis di^torum. 

Flexor profundus digitorum. Extensor minimi digitf. 

'Flexor o^is metacariii minimi digit!. Kxtcnii^or indicis. 
'Flexor brt-vis minimi digiti. 
•Lumbricales. 



FLEXOR 8UBL1MIS DIOITORVM. 



287. 



'loleroafiei doreuW. 
*vVbcI(ictor minimi digiti. 



Addudon. 



Of tho five of tliese nm«rlc« locaUtl mainly in the fon-iirin two arise from the 
liimicriLi^, one from tlie linmvnis, r»<iiiii', ami liliui, iiwl hvo from lliv iiliiu only. 
Every otif in the group is inwrtcd into otii? or more of Uw liiip-rw, cxccptiiifr the 
tk-xor of the- fifth nietucarpn) bone, wliioh i* admitted to tliin vomimny of finger 
fivxore on aocount of tfw- itiinilarity of ila action. 

Flexn- gtibUmis Difi- 
tonim (Fi{,'s. S2:J-?2.>1.— 
"Tiledopcriioial fifxorof 
the digit.-;" — meaning tlic 
four fingeri a.-< dii^tiiiguiiih- 
ed from the lliimih. Syniy 
nym, Bex or jierfo ruins, 
" the perforated flexor " 





uiMliTU- |.. fi I .■ ■ ■ '.'iiclnn 
uf BrxoriimfuiiJui. iTnluLJ 

— from the o|M-nings 
tlir<>ii);h whieli lli<- tttii- 
donii iif the deep flexor 
ra.-<9. •Situation, in the 
front of the fon^arm 
and h»nd, deew-r Ihim 
tJie ilexors of tin- whole 
band, lint sii|M-rfieiul 
to iht- other flexor*, 
Oriffiti, first hea<l : the 
inner condyle of the 
humerus ; fle(win<l head : 
the inner border of the 
eon'noid process of the 
ultia : third hend : the 
ohLiipii' liiH'iind part of 
tin- uiiterior border of 
the niditi-!. LUrrriion, 
downwimi to all of the 
dipt* hut thv thumb. Iiuertion, by fonr tendons, eaeh to the n'ul^ of a sx-eond 
plmhiiix. Ak the tendons pass through the annular bcanient. thorn- for the middle 
luict ring-fingere are i-ide by side in front, the others behind them. Eaeh tendon 



toram nf t(k1i1 nMe. iTrclut.) 



Via, ft«.— Fli'iniJiiihlimlidli^Winim 
uf righl ildfM nultlnv ■lid atlBclimcul 
arnti. (P. H. U.i 



288 



THE MUSCLES. 



i.H a<!n>m{i:iiikil by ft tondon nf t\\« fioxor profiindiiH, and pcrmilM tlii> pnnoago 
till? lalti-r ilirniigh a split which ciccurs ojiposite the first phalanx. The >f]mnifod 
halves licciniif iiiuKhI bohiiKl the Icmlon ot ihfi ileep flpxor, oppiij-itc the bam- of riii- 
WK^ond phalniix, but iitniotit imuicd lately M'punitc ag:iin, una are iiiMTtrd iiilo llii' 
sides ot the wcoiid pbaluiix, Tb« tendons are bound down to the j)halan|^ bv a 
lifpinieiitoiis (^he.'ilh. Adion, priiimry, flf^xion of (he sfc-orid jilialiiiigvs ; feeeoudarv, 
tli'xion of firsl phidanne?-. ^Vmr, tiit niediun. 

Flexor Profundus Dieitonim (Figs. :i'i6-:t28J. — " The dvep flexor of the digits " 
— mcniiiiig the Hiif^rj^iis 
<lisfiiigiiiKhi-d IVoiii the 
ihiiiiib. Sipiiniifiii, fli'Xyr 
pfHbniii.'," Ihe perfiirat- 
iiig floxur" — fmm the 
fni-t tliHl it8 four tendon;* 
pfrforatetlieoorreapoud- 




-Mairta 

thD 



Urn 
•Ire put 



(Un'lH»|K'[f"'"l"lB't'llll011 of flfiot 

■ubllmb. iTvitul.) 



iiijj (("ndons of the flexor 
iiubliniiH. Slfuntifm, deep 
in thfi front of the fore- 
arm and hand. Origin, 
thi-ce-foiirlhs iif llie inter- 
nal and ventral surfsipciof 
tile ulna, the iuljii<^^-nL half 
of tlif iiilcnivcoiiji inem- 
linine, and rlie eommon 
ttndon of il mid ihe fli'xi.ir 
and I'xifiiscir t-arpi ulnariH 
mi the hind bopdcr of llic 
ulnn. Dii-fctitm, <)owti- 
ward. Innerfioti, each of 
the four tendons into the 
front of the base of a laft 
rni.3'/;-FlciorpR)run<liuiU|ltonim phalanx. Each tendon 



oTrlEbt side 



outUnc >»d Mt.a.n«MK- ^,.f„rates a temtoll of thc 



Fw. _ . 
rlRhl IbRBnn. 
Uyvc. iTnluM kroM. iV. H. Q.) 

au]ierfieial flexor o|HMwil<' 
the fir^t phalanx of the fin^fer to wliieh il lielongH ; each is bonnd to thc (ir^t and 
seeond phalanj^s bv ligmneuts ivhicli form a tilieath (■onimun to thi.i and thc i'nl>- 
liniis tendon. A<4ion, flexion of third phalanges primarily, and, after thin, flexion 
of Ihe M^eond, nnd, slightly, <if the first. jVrrrca, thc ulnar and thc ant4-rior inler- 
oespoii.4 braiieli of thc median. 



FLEXOR BBEVIS MIXJMI DWtTI. 



289 



Fl«xor Omu Hctocarpt BUnlrai Digttl (Ktfr. 329).—" T I if r flvxor nf ih<r tiMila- 
curpal bonp of iIr- l«t>t dinit "— •■ '., <>•" Uk- liitk- liiigi-r. Si/noNguii', iH)[k>> 
DPitii mtiiitni iligiti, ami ii{>]iiiiii-ii-< ilipti i[uititi, " iIk' <iji)Mnitig iiiunrli- of \\ui U-oril 
(or tiOli) •li^il," Ml cjilldl fniiii it." iJniwiiiii; (lit* liyfMttlM^iiar ■■iiiini-iK-i' tiiuanJ tbc 
ttifimr, tliiu nurmwiiig ami di^ejioning the palm. tiiitiuitioH, deep in the Iiypo- 




-HnMlM of Ittc riithl iKtiii. Tti« abilui^utn «f tti« Ihumb anil llltlv (Inxar have iwTn nimnrMi* 



thvuur ciumonpe. Origin, the iinciform procewi and the »iiiiular ligament. Dirre- 
tinn, dounwanl und tounrd the tilniir mni^in of the hand, him-rlion, the whole 
of (Ik- uln.tr i-idv of tlu- flfth nietiirarpiil. Artion, tlcxiun of the Aflh niflurai^:tl 
mid »\\y:\\\ sddnctiun towurd the niid-liiK- of (Ik: hand. Ncrrt, l\w dicp liniiii:h 
<if ihc tilniir. 

Flexor Brerb Iflinimi Digfti (Fi|i. 323).—" Thr short flexor of thv liact digit" 
— I. ••-, rif dw little (iiigv-r. Hipumym, llt-xor digiii qiiinti bn-vi*, " the churt Rexor 
II 




290 



THE MUfiCLES. 



nf the fifth digil." Siiualion, sahcaiaaeously in the centre of tlie hypothciiar 
pminenoe. Origin, the unciform proc;cs« anil the annular ligament. Virfdiort, 

(lownwtinl fin»I Inward, /nnfrt/on, lh« 
biiisc of the firwt |i]i»limx of tJic little finger 
iin (he iiliijir bi>rikT. Artioii, flexion of 
tin- liot pliiiliiiix of ihe little lingtT. 
jVftTc, tilt- <ii-c|i hniiirli of the ulnitr. 

Lumbricale8(riji:. :'.2'.i). — '-The Mirth- 
worni mnscles," from their fancied n-»eiu- 
liliiiiee to unjrIe-wtirnis(/uwifcWcj), .Yiitw- 
bi-r, fnnr. Earh is a Iiinihrii^liH. Situa- 
thii, in thi' |ialm on lln- jilane of the 
flexor proftindiiN di^itoniiii. f/rStjinot 
the flrnl ;iii(i sci-(in<i : tliv |Kiliri)ir neiicct 
nnit niiliiil liuiil<-r of the uorrcjiondiii]; 
(tci-)) tli'xor tendon ; nf the thirtl nml 
foiii'th : tiic two tendoim between which 





Ppv S» Mutpl« In iIh! ilunrnm tit (he right fgff- Fl'i. Kll..-Exlcimir rnmmuiita digiloriim oT 

*rtD anil ImikI. ITialut.) liKMitOe: DOtllncHOd alliichiiiciil-knM. <F. H.O.) 



EXTEXSOR COJfJfUXJS DIGlTOItVM. 



291 



■ 



each iwnectivcly lio^ Diretrfitm, don-iiM-urd aix) then backward, on the radial 
pij* iif tile digits, fujfrlion, each lo (he exteii.tiir coromniiU IcimIod of the ixirre- 
ejMjndiiig finirrr on the niiliiil «iiK' i>f ihe lir^t ]ihjilanx (Fijr. ^2). Arlioii, flexion 
ofttir 6r*t |ili:iliin}^-s!iiid i'xk-ti»i<>n of the tiocuiiil an<) thiix) jihalanRVK. Tlif first 
and Ktt-otxl »li};hllv u)*diict thv index aod middle fiii^Oi from thi- middle ItiH- >>f 
thv h»nd, ihv thiix) aud fiKinh vliffliily adduet the rint; anil little liiif^ni U> that 
line jVeirvjn, the iticdinn fur lh« outer two, tho ulnar for iIk- inner two. 

Ezten««r Communia Dlgitomm (Kig«. 330. 332). — *'Tli(! coinnion ■•xli-N.'>or of 
tlio dijfit.-*" — i. f., of iln- fio'^iTs, an dtritingiiiKlicd from th« tliimib. ^yiliuitioii, 
BUperiKJal on tht- liack of iht; forearm and hand. Orit/in, the outer condvk of 
lh« hatnenui. Dirr^ion, 
dowuwunl. Iti*frtion : each 
of th(^ four tendotu lii>al)y 
divides into three slips o\t- 
pO!(ile the first phalanx, and 
the middle one iis nllwlu'd 
to the buck of the l>a*e of the 
second phalanx ; the ottH-rs, 
after unitinfr, are attached 
to the back of the hoMt of 
the thinl phalanx. The first 
teodon receives the inwr- 
ticMi of ihe extensor indicia 
atthebafieof thefin^^r : the 
foarth tendon unites wilti 





MMEMUkaaoT ibe Inter- 



Flo. Xn.~Ei<rn">(nilnlial i1J(tll 
0( rlRbl ildc: omllne ftnd aiui'h- 
awtil-amu. I'TnluLi 



rii> 13(.— EiUniMT indleb of 
rtlht litlc. o<illlii« aiK) atuch- 
nwDl-ai**!. lY. II. U.) 



that of the ^xtcnxor niinimi dif^ti at a Aimilar point. The fonrtli divi<le.« : one 
pari unitc)> with the tendon of the niediuK, llu- other wi(h that of the extensor minimi 
di^ti. A >^l«>iig band rtin.-i obli<)iiely downw:mi and outwuni fntni the thin! to 
the second tcndiin, and a slighter, transverse hand eoniicctis tin- first and second 
tend«im>. Aflioii, extension of the fin^rs. The oblique bninchi-A at tho ndcs of 
the ililnl tendon greatly limit the extension of the ring linger, when its immediate 



1 



292 



THE MUSCLES. 



ndehlion: are fl(>x(>d, and tins faot t-xplains the (iiflBculty experienced by ptnniats 
in lilliii)! the aimiilans m-panittly from the keys, .Vc/cc, the [lo^te^ior inlcruteyeoiiB 
bi':U)i.-h i.tf tlic inii^icnlii-spirnl. 

Extensor Minimi Digiti ( Fifpi. 3:10-333). — "The extensor of tlie sninM**!. digit " 
— I. c, uf th*- little finger, Si/wmiim, extensor dijrili qiiinti |in>|iriii*, " iUv jimiKT 
cxteiiMor of the iit^h digit" — "prnjwr" to div'tiiigiiiKh it fivni iliv fKirl of liie 
extiMi^or eoimiinnis wliieh acts tipon this finger. Slh'iiliim, in tlie Imek of the 
forciimi and liand. Ori;/in, tlic ejctern.nl condvle of the hnincnis. /mu-rtifin: its 
((■ndon, whieh i-* commonly sjilit, hiend* with the fourth tendiiri t>f the esten.^or 
eoinmimi.4 alw^ve the tMi'tui'ni|M>-|ilirihinge!il joint, .-ind the re-inltinji tendon jroes 
lo the >ieeoml ami third plialangi's of the Utile finger (see extensor rf<nimnni!i 
digitornm). Adion, extpn!*ion of the fceond iind ihirri phalangvi< of the little 
finger, ym-r, the poHterior inn^rfiiiwi'oM^ hnineh of the miiwnlo-spiral. 

Extensor IndicislFlgs. 819, S.'M). — "The I'xtennor of the index finger." Syno- 
nijwii, extensor indiei^ proprinw, "the pro(M?r cxtennor of the index finger" — 
"proper" to dietingnich It from the pnrt of the extensor eoDUnnnin which acts 
il[K)n this digit : the indie;itor miiwle. f^Hwiliim, the IxieU of the lower part of 
the forearm and Imiid. Origin, the back of tlie ulna below the extensor longus 
poUicis, and a little of the interoNteonf^ menihRine. Dirivtioii, downward and 
ontward, Inerrtuni, the lir^it tendon of the extenwjr oommunte djgitorum, near 
the metaear|X)-|iliiihinp'iil joint (aw. exlvnsor oomnmiu^ digitonun). Action, exten- 
sion and slight Hihtuelion of tJie index. AVn.*, tlie ])oiittvrior intoros*oou» hronch 
of the inu»i'nhi-spind. 

Interossei Dorsales (Fig. 335). — " The niu.-*cle3 between the bones on the bftck " 



THtHB oeastL 
initnotsiaui 




COHO osa«*L 

imtlOlBtOUB 
nnST DOHSAL 

iMTinosscoum 



Flo. MiL— IntTc w l dtiri«1ci of right h«nil. The line x E I) Itiat frcm whlcb aMncUuu ii tiudf. (Twlvt.) 



of tlie hand. Xumber, four. The first and hit^st Is called abduffor imliei*, 
" the abductor of the index finger." The abduetor minimi digit! belongs fiino 
tionally in thii^ groups bnt it is not interosseous, ■SVV'tn/i'oit. one in e«ch nieta- 
car|>al intert^pace near the donral a«peet. Origin, tw^h frotn the two bones 



ABDUCTOR SilXlJil DIGITI. 



293 



br-twcen wliii'li it lies, fJirffiion, dowiiwartl, Jnnertion, each into llie hai>o itf a 
fir^il |>hnliinx, and aUo into the ejcten^or trmlon of the sunie finger, thf first on 
the radial fride of the iiidvx, the HisTond on thi- nidiiil tiitk- of th« tnetliuii, th<> 
third on (tiv ulnar ^i^idcof (he nK'«liii», the fourth oti the uliiiintidc of the annutiiris. 
Arimn : mc-h HlMliictri from A line (.'oincidtnf* with the long -dxtf of the middle 
fini^T. This digit, hiiving two intomR^'wi iiiwrted into it, i* iihdiicted towanl the 
ndiid i^idf hv our, iiml towunl the idnur sidi- hy ihi^ ollu^r; lhn>f, i-aieli iti tnrt) 
bKiimcs an itddiiiTinr, fi>r ilw Hngi-r hi^iiij^ alMlin^*Hl liy om» i.* tlu-n n-slon-d lo the 
Riid-lini- 1^1. r., a(l(liiirt<-d) hy iht: o(h(^r. They al.-io flex the lirnl i>lialiii)g<-4« siii) 
extend the second and third. Xerve, tlie deep branch of the ulnar. 




Fm. XM.— Mutcln or Ihc Ti^i patan. Tllv (HlDilLril lirrtit !• ruOvctvil t.. tin tiltmr ildu. (Totul.) 

Abdnctor Minimi IH«Hd (Fip. 336).— "The nhdnctor of llic l.-ast digit"— i r., 
of the little linger. Synoiipn, uUluclor digiti iiuinti, " llic ahdiiotor of the 6fth 



294 



THE MVSCLE8. 



digit." SltHation, th« ulnar bnnlpr of tJic tuind. Origin, i\w pisifnrni. Diref>- 
firm, <townward. Iiufeiiion, thp ulnar Iwwdvr of tlio ha««' "f the first phnlaiix of 
tlic little lin;;pr ami the tendon of the fxteiisor minimi digiti. Action, abduoiion 
of the litllc finger. jVcnv, the deep lirancli of the ulnar. Its function put." it in 
the proup with Uic iiiterossci dorsales, as it draws its digit from the mid-line of 
the Imtid. 



IHTIBOUIOU* 




THine MiKiia 

■HTtN«a*C»U« 



na. &n.— lalerourl palmnrvn <^f rtgbl lianr). Tbr lln* »< U Ui>l lo whiah adducUan tii tnul*. (TgslDL) 

Interoasei Palmares (Kig. 337}. — "The inu«;K')( beiwii-n the Imix'!* in theptilni." 
Siiii'iiiifm, iiitcnwsci voliiri's. ynwfu-r, ihrif. .Sltuuliuii, in ilic m-cond, third, imd 
fourtli TiieUifnrjml iiitcr.-J|Kioes, ne:ir tli<- jiulniiir ourtaci: nf thf lionos. Oriyiu, thu 
first : tho ulnar ^iih; of \hv si'<^ind mclai-jtriKil ; the HcnTond : the radial i«ide of llie 
fourtli nictiinir{)iil ; the lliinl : the mdlnl side of the fifth nicta<-ar})id. Diretiitiii, 
dowiiwuril, hiwrtiiiii, cju-h into tin- ^ide of the base of the fiol piinlanx of the 
digit iriitn whiiw ini'tacJirpiil Imne it arises, and aUo into ilii> oorre^jM nidi tig ex- 
t<'ii«)r t<-n<l<>ii. Arliiin, <-nch adiliu-is Its digit toward the iniddle tini;er ; also, it 
Ilexc!« the (irsl pluiianx nf its digit, and extends the second and thira phalanges. 
-Wrre, tlie deep hranuh of the ulnar. 

^^ MUSCLES MOVINa THE THT7MB 

^H and its Metacarpal Bone. 

^^H {ThoMi »nllr<'lv ill ilic liaiul »(v iiiilii'>i[>-il tiy k hIkF.) 

^B Flfmrtn. ExiaxHom. 

^H *FI«xor tmi» inetncar])i pollieU. Extensor o^ix metacairpi ])u]l!cii(. 

L 



Flexor longun ]>olllciti. 

vlWiMrtor. 
*AI)diiclor pollivis. 



KxtviiHor luDgiis |>ollivis. 

Atlductor. 
♦Adductor pollicia. 



MUSCLES MO VIX6 THE THUMB. 



2fl5 



TIh' mov^niffits of tlii' firsl m(-tiio:tr|>iil iMitio iin- so rl(x*<'ly iire<<>('iii(<-(l with 
tliw of till- iitwUn^i-n u'liicU il <sirni-n, tliat it is profitabli- to otitiAiiltT iiis f|K-ri»l 
mii«^ti-K in tiK- gn>U|i willi tlia^te of the thumb. The toi^^r nanio nl' tin- nu-lu- 
<wr|Nil floxor i.s pri^ferri-d as iodicating ito action sHwell as " opponeii.'i |K>lli<:tH," 
and at t]ie wime tim« «xprp«Ainf( lunnb more clearly the antagonism bcitweeii it 
and the nn'tararpal estensor. 

Flexor Ossis Metacarpi PolliclB (Figs. 338, 329V-;" Tlio flexor of f h« meta- 
carpal bone of the ihunib." Synonym, ot>ponen4 iKiIl!<.-ii?, " the op)>otieiit mtlftcle 
of the thumb" — referring to its action id opixusing tbe fheiiur emineiK-e (o the 
hypotbenar, so that the palmar hollow is tlt-cjicucti and luirruned, nntl a body 




Fn.Sft— AditniTtor tmUtcta. R«xot owit nHUnnd iK'llioli. >nil pnin>U» qiutdiMuit. ITnrliil.l 

between these niU8ciiI:ir mounds can be grasped bv them. SHuatio», deep in the' 
tlieuar eminent. Origin, the jHilmar aspect of tdc tmiK-zium and annular lign- 
meiit. DirtetioH, downward nnd outward. Inattiimi, the whole ^hnl't of the 



296 



THE MUSCLES. 



toetararpal bone nf tlip tlmnilion Itfi ntiliul t^idc and anterior luspcci. vlrijon, flf-xion" 
ami inwjinl niljitioTi of iIk' first iiR'taiiiriHil botR-. Nrrrr, th« median. 

Flexor Brevia Polliciii ( Fip. 3211). — '* I lie slmrl flexor of tli.- tlni mb." SitmtHnu, 
dt'L-p in tile (hcTiiir iniirn'iiii', Oriyiu, llic onU-r (Mii|H'rfi(')iil| liwiil : lln- 1nt]R-7iiini 
iin<l tlie diiUt two-diiriln of iho iiiuiiilar lignnionl ; iho iniK-r|<l(H-|i) lim<l ; tlir unix- 
iniiil [Kirt 111' tliv firnt iiit-liicar|ba! im rlic iiliiur ."idc Dnrrtimi, tiowiiManl iiiul otit- 
wanl. InMeytiiin, ilii* iitiU-r hrad : the oitlor ni<]<- "f the Iwisc of iho fin-l gihalititx of 
thft ihuirib, with Uie abdiiclor jtolliciB ; ihe inner bomi : the inner .wlc of ihi- ^ine, 

with the adciui'tor jwlbpis. In ww^h tendon of 
insertitm in a, M>Minioid bone. Aclio^i, fie.\ion 
of tlif first phalanx of the thumb. .Witc", 
outtr head: the median ; inner head: the ulnar. 
Flexor Longus Pollicis {Y\g.f: 326, 83fi). — 
"Tlic lonj; flt'Xi>r of the ihiinili." Silmillon, deep 
in the front jmrtof the forearm, and on tlie ]iai- 
nmr as|H'ct i>f tht- thnmb. (/rlyin, tlie anterior 
Khrfanc iif the radiuw frcmi the oblic[iie line In the 
ii|»|H'r line iif the pronator qnadnitn^, the adjacent 
jMirt of the inlerosseniie inenibrnne. and somc^ 
linif.< the bitw- of the etironoid pnx'ess of the 
nhia. hlrvxiliin, douii\faril (u the wrii*!, then 
downward and ontwuii), the tendon )>ii.-Aing bi>- 
twi-en till- two iMtlni." nf innerllciti of the flexor 
breviH jMilliei.i. fmfHhji, the front of the bat* 
of ihe hint idmliinx nf thi- iluimh. AHlwi, 
flexion of the last jihalnnx of the thumb. AVrrc, 
the anterior intenl^'-ec•llH bninch of the median. 
Extensor OssU Metacarpi PoUicls ll''i^». 340, 
341). — "The extenwir of the nietai'iir)Ml iHini* 
of the thnmb." Si/iiout/iii, alnlnelor lonfruN [k»l- 
lieifi, " the long abibietor of the thnmb." Slhai- 
thn, dt-ep in the lower two-tbirdn of the Iwck of 
the forearm and in the radial Mde of the wriiit. 
OrU/in. (iniiiil areas Iwlow the aitaehnientM of the 
Mipinator on both radiiih and ulna, and the 
inte-riiK^M'iHiH nii'nibnine between lliew siirfaees. 
iHitvHiiu, downward and outward. Jimniimi, 
the luiM- of iho niefacariiid bono of the thnmb, 
Ariirin, extension and abdnetton of iht- nieta- 
car|Kil bone of the thinnb. AV.rr, the piwterior 
inieroiv-coni liri)Tic4i of the mnHeulii-siHfitl. 

Extensor Brevia PoUlcis (Ki^rs. 340, 342).— 
"The short fixtensor of (he ihiimb." Siim'i'nm, 
extensor primi intennKlii pollicis, "thi' extea-^or 
of the first uhnlanx of the ihunib." Sifnfilion, 
deep in the lower half fif the biiek of the fore- 
arm on the outer side, and in the melaearpns. 
Om/iii, asniall area of the mdin-i, just below the 
extensor os«is meta<-ar|>i polliei^, and the adja- 
cent |K>riio]i of the inlenmseon!- membrane, 
IHirrh'nii. <lown\v:in;l and outward, Jnwt-tion, 
ihv litivk of the base of the first phalanx of the 
thinnb. -IWfViH. extension of the thnmh. A'erce, 
the posterior intenw(<eon» braneb of the iniiiu'iilo-fpiral. 

Extensor Longua PoUicis ( Ki,;s. 340, .H."!).— " The long extensor of (he thnmb." 
%n"".7"», extenw.r si-c-nniti iiitenxslii polliels " the extensor of ihe M-eond phalanx 
of the thumb." Silwiliun, deep in the lower half of tlie back of forearm and in 




Flo, xai.—Tivxar IfrtiEin poUleli _. 
rlBlitaMr; uulllnc and allncIimcia-nivM 
ir. U O.) 



MXTEXSOB LONOU8 POLLICIS. 



8B7 



I 



L MOL-^lDKln Id miiMl rc(lan ot rlRht hmum. and dscp uiucIik Id lU dortuiu. iTmcuuj 



298 



THE mvsci.es. 



the thumb. Origin, the middle tliird of the dor^l FUrface of the ulna, lielow the 
extensor o«Ufi§ melai'sirjti putlicis, and the nt'ighboriiig pjirt of the intero.isM>uft 
iiicmbniiR'. IHrpcfion, downwaiJ and outward, hmrfiiim, the back of the base 
of thf- l;i.»t jihiilniix of tJic thumb. Action, extension of the last |ihalanx of the 
tUiinil). Arnv, lh<.* |K)stcrior inltfrowMLoiis branch of the miii'cii[ii-(-|iira]. 

Abdnetor PoUicU (Fig. 336).—" The abductor of the thiinib." S^nmiimi, aln 
dix'lor ]Hil)i<'is htt'vis, " Irn- kIioH ahdnrlor of tin- tbnmb." Silimiioft, f»\K-r^ii%\, 
■ 111 iht- radial >idi- of lh« incti«-jir]iid bunc of On- tlnitiib. Origin, tin- frtini of the 
ajiiuilar litriinfiit, nnd, to a slif^ht t-xtoiit, iIk- InijK/iiini iiini scaphoid. iHm-liim, 
downward and outward. InKn-flon, tlio liaM- of (he lli-^t phalanx nf ihi- thumb on 
the outer ndi.', in common with tlio ouli'r inwrtion of the iloxor brcvis |>ollicU. 
Action, abduction of thumb. .Wiv, the median. 



L 




I 



Fia.Ml -Rxtciuornwlj ni*U- Fin. M!.~1C>Uiui<ir brvvii pal- Fir.. Ml.— EilfOMt lonrupOl- 

rari'! i»llli'lir>rr1ihl aide: ouUIno ncUnf tlflhl ilJii: 'mlUw miil at. lii'ln <>( Hiilii aide. oalUlw uM tV 
■iT<f iiIi>e'liiii«nt.Brnui. iP. H. Q.) Uchmeiitun-u. iK.lt, <■! t*t'l>in«iii-ur«Hi. tK.U.U.) 

Adductor PollieU (Fig. 3:W).— " The iidduidor uf the tlinmb." Siluatim, deep 
in tin- outer half the [)abn. Origin, niii- liwid : the ii!« muf^num, the htu*^ of tile 
W'cond and third uictacar[mU, and the annular ligament ; thi- nlher head : the 
lower two-thirds of the thin! nn-tawirpai. Dinvtion, tlie upper part ; downward 



J'AL.VARIS liltHVIS. 



299 



and oulwanl ; the lower pnrt : oulvmiil. In»trtion, tlio inner ni^le of (he base of 
thi- first |))uil:iiix of the thumb, in common with ibt- inner inxcrlion of the flexor 
brev'is |>o)lieit!. Action, ad due lion an<l flexion of (he tbnnib. .Wry, the nhmr. 
The iipiier portion of this muM-te is often de)*cribed ae adduvi'tr otifitptti^ pfMicU, 
and iIk- lower as tuldwtor tranm-ei-nug po/ficu. 

Tbo interos^ei, tbe uMuetor and a'Idiictor polltci?, and the abdnctor minimi 
digiti mil)' well be vonmdered tiif;ethi-r m eonslittitin^; a di)(tinet ))hyi<ioh>f;ieul 
pninji. the nii-nilxT* of which iiR- ouni-enK-^l eilhfr in .tbduetion or addlielion, or 
U»ih iFij". 344). VAii-li of tin- five digii!« hj'» uttiiched to the biwc of it* iirst 




Fie. U4.— niBcn™ «lioiiTtliE the Bmnjirmtnt oflhi! addurlon >n<t ■bdnt^tnn nr Ibt ■llKlHOf tha hand. (F.H. A.) 

phalanx two of these tea muM-lo», one u[><>ii the radial, the nthi^r npon (he ulnar 
side. The thumb fias tho aMmior and mhiuctor pDllkiii ; the Jorefingcr has the 
fird dormtl intrryuv^mm (iilHhi<-tor indiei-i) and the frM jui/iitiir hih-rwticouJi (fh« 
atldnetor fif thi- inilvx) ; lh<; ring finger lijii» tlie tirciiul piilmur inlirnnHfou* (the 
a<lduot<)r of the annnlarisi and \\\^ fonrOi tlormii inUriMwoitg (the ubdiictor of 
tiiir iinniihirir') ; llio little finger has tlie third pnbiutr i»lrrf»uif<niH (tho addnclor of 
tlie hawt digit) and the abilador minim! iliqili. Tlw hiteral npixment ninsoles of 
tin- mtddli- finger are the M(V)W and thtnl dumat interontieou^ — the one drawing 
the digit from the middle line towaixl the radial side, the other drawing it from 
the middle line (owanl the ulnar side — (hat is, both are abduotors, Iiii(, 
the finger being displaecd lalerallj" by one of these milHcles, ie restored to 
the middle line hv the action of the other ; and thus it is seen tliat the second 
and third dorsal intero^eoufi are, ou occasion, adductors an well us ubductorv. 

One other niuaclc musl be dMcribed, allhuiiKli it is so iliniinuiive and Dcarlf poworlnw thitt 
a do«e not deserve a plaeo in any of the Kpn;ifici] ft>^np«. 

Palntuii Breris (Fift. 336.) — "Tlie uliort pHlmar inustle." Si'luation. subcularieoiw at 
Ifae pnixiDiiil pan ut' the pahn. Origin, tli» inner bonier of iho palmar fascia ami the aitiHIo 



M 



300 



THE MUSCLES. 



(if thn anniilur lIcnmciTt Drrfrtian. inminl. Intirtlon. ilic Klein at thn inner border of tbt 

talui. Artiim. wrinUIJiig llif skin ul 
iw uf the pikliu. Xerve^ the ulnar. 



Calm. Artiim. uriaLIJiig llii- nktii ut' ibi' lij jHitlitritir cuii»i--iii.'<r uii'l ali^'iilty <leepeniiig the hxA- 



Altfioiigh ttic (■lflN<ifi<'4ttioii nf the muttc-los nf the npiwr limb wim-h lius beon 
mvci] is rc^inli'il il* ilic iiiiint liclpfiil to x\\i- lt-ari)cr ana lo tlu- pnutiitioiKT. it is 
• lo.tirnblf tlinl llirv sliimlil bi- simiifd (mm (iiIht |HtiiiU of vifiw aliw^ ; umi, tlu-rv- 
l'iin>, It n>j;iiitml (■lu.viiUraium is h<ar(^witli prcM'nU-d, \wr<e<\ upon thu Mlii;ili<m of 
the niaiii piti'tioii i>f pach ot" these etructiireH, 

Mi:SCl.EM WHICH MOVK THK Ul'l'KU LlHU, GKOL'I'KI) ACUOUUIKti Tf> THKIK 

IjtICATKlN. 

In Ihr Huprrfinid LtiyfT of tfir. H'li-k nf thr Truitk, 
Trapezius. Lati^Kiinii^. 

Ill Ihi- Si-i-oiul Lntfrr <>J ihr Hiu-k nj thr Ttimk, 

Ixviilor s(a|)iilwr. Rliombi>iiIcii!» minor. 

HIidmboitloTiK mujor. 

On th4 J-'ront r,f ttu- Chrxt. 

Pectopftlis luttjor. PTOtoralis iniuor. 

StibcUtviiis. 

Oti Ihr Side <>/ thf ChrM. 
SermtiiK magtiuit. 

In the Bark Part of (Ac ShouMrr. 



Supni'^ltiiiutui;. 
Tltc's major. 



Inf^ll^|>iIlatuf;, 
Ten* iiiiiiur. 



Riilw(!a|mlari8. 

In thf (tutfr i'dii of the Shmtltter. 
Deltoi<)eus. 

In ike Inner Siile of Ihe Arm. 
CV) n»« »-bnioI liiil i s . 

In (/«? Frmd Purl nf thf Arm. 
Biceps Bexor cubit!. ItruohiallA 

/" Ihv liitek P'irl nf Ihr Arvi. 
Trie(-]is cxtfiiRor cubiti. 

In ihe Froni Pari of the Foirtirm. 

I'munt'ir UTi-s. Flpxiir i-arpi radialis. 

[KlfXDr] imhiiiirlK I()ii);ii#. Flexor carpi iilimris. 

Fli-Mir Mibliinin ili^itoruai. Flexor prufiinJux lUgitoruto. 

Fk'xor liHij^ii.-- pollirU. Pronator qimdratiis. 

In the Outer Part ftf the Forenrm. 

l)r.tchio-rj<iiulti<. Rxtoiiiior carpi raJialis lotij^us. 

Extensor carpi radmlifi breris. 




THE MUSCLES OF THE LOWEH LIMB. 



801 



In the Back Pari aj Ote Forrarm. 

ADconeUR. Extcnsnr a«ih< melacarpi ]K>llicii^ 

ExIeUMtr oooimtinis diritanim. Extenfior brevis |Mllk-iii. 

ExIeiiHor minimi dijEpti- Extensor Ioii};uh pollids. 

Extensor carpi ultiiiriif. Extensor latlicts. 

Supinalor. 

In the Thenar Emiiwtn: 



Alxluctor |io1lioi<^. 

Flexor <]i!*i« mi'tu«irpi (mlliciit. 



Flexor brcvii' poll ids. 
Adductor pollicio. 



In the Ilifpothfnar Eminenrr. 

Abtluctor minimi dij^ti. Fk-xor brt-vu minimi digit!. 

Flexor umIh mvlucnrpi minimi Falmurix bri'vis. 

digiti. 

/ft l/u! Palm of the Han't (trtiiyen thi- KuunftMw. 

Lnmbrivuli^i. Iiitc-rumi'i pulmxrcs. 

Iiircrftiw^ doivuk-j*. 

TltK i>tu<)ent U ndviwd to niako nthor ola.t.-«ilicatir>n{i of Iho miiw^lo* moving 
the linilit*, in rmlcr to obtniii n.- o<)m|iI(-tf ii pmclicjil knowled^i;^ of (hem ii.« ikh- 
sible. For examjilp, let him Rniiip tlii' iiinsclts a<votilinff to the jMirtu irAicA tAry 
connfet, under some sucb headings as tiie following : 

Coiineclio^; tile head, neck, and (or) trunk with the shoulder. 

Connet'tini;; the tnink wilh the arm. 

Counectinj; the shoiilcler with the arm. 

Connectintr 'he -ihoiiMer with the forearm. 

Connecting the arm with the foreann. 

Connecting the bones of ihe foreami. 

Connecting the arm with the band. 

Connecting the fwrcurm with the band. 

Ouiiiiecting the guirte of thi- bund with each oth«r. 

A^nin, iH bint eiiiimcnito the mnK-Ie.s whieb would be ml bii pfane nfcttong 
matlc Ittumrrnifltf rhrouyh /Ac /imfi at tiiUVrent levels, 1U^ for example, lit llie mid- 
dli" of ihe arm, in the lower llunl iif the iirm, in the upi>er quarter of tlie forc- 
iirni, and wi on. The mori' wiiyn In- adopts for eini^idvring ibe iinbject, tin' more 
exaet, |H^rmaneut, and ui^ble will In- lus kudwlitlfre. 



THE MUSCLES OF THE LOWER LIMB. 

In nuking a physiological elaasifieation of the mnseler. of the lower limb, 
Mfc notice at the outset that there i.-* a great differenec between the mobilitr of the 
fii>t M-^ment of the upper limb ami that of itM boniologue In the lower: tlie 
shoulder i» freely movable, the hip is alniom immovably fixed. There is no 
group of mu><vIeH devoted to niovnig the pelvic ginlle at all com^tarabie with 
tbi»i' eoneerneil in the movenient-; of the shoulder. The great mu*cle^ of the 
niMlominul wall lift the front of the pelvis ; but this is accom|Kitiied to no iippn- 
ciable exierit by movement of the hip-bones at their iirtienlalion^ with the wie- 
nim, but by ibc cnn'ing of the vertebnd eidumn. The verj' Inf-oni'litnl jl-«iil4 
jtarvitA i.*i .<u>metim4>:t a^uierted to flex the iiclvis ; but thi* may wtll be (|U4«(inn<^, 



902 



THE MVSCLES. 



and the mUft(;lo, wliicli is frcttueiitly atiwiit, prolmlily \\vt» iMn-tfi'iri t'si-ciit in ticlit- 
eiiiiig tlio iline faseia. No group iif miiscW, llnri-ii)ri-, will l)i- |)n'j'cmwl iu> 
avtins Kpoii iIh' hip. 

movements of the Thi^b. — The hall-and-Horket Joint at ihe hip perniitf) raove- 
mi'nt of tlic tliigli in overy (liriftinn. Thiit furward ie trailed fitxiow, harkwnrd 
is eslriitiim, oiitM'urd iw nhiiudioiif inward is atUtudliju. Jlolaliott and cUcumdtte- 
liim an* like tin- wiino movtmeiite in IIk- upper extrt-mity. 

Movements of the Leg. — At the knix' tlie Joint is a ningc, and th^ movomentfi 
of till- Irjf an- fynviinl. whifli is rj-h-ni'iiin, and Kiekward. which is fiexion, 
BciwiH'ii the lwi> lonj; Imni-* nl' llio lo(i ihvre is n<» movement e(>ni[)iirabl« with the 
pronation and nnpiniiilon nl' the mdiiis. 

MoTements of the Foot. — At tUlkAiiklc ia anollitr hiii^' wiih iinivciiiunt of the 
itwt l"orwai\l (^upwaivj), wliicii is Jii.rlfin, and Uu^kwaid idownMunl^, whicli is 
exUfUiitin. Till- liit<-Ril iiiovciiicnls of the fool arc cliicfly at lh<' a^tn^ralu-calcuncun 
and the mcdin-Iarsa! ailii-iiliilions. 

Movements of the Dieits. — Tlif m<-I:itar»o-phii1iinfr(.-al und intorphidunp'ol 
articulations art; alnio.'^t idcnlical with thi^-ir )iiiinoki);iic.-< in the hand, (In- main 
difi'crt-iice lieinj;; thai the fiw inctii tarsal i.t like all of it.- fellows in it.- ])nu-li«il 
iiumobiliiy, and thus the halhix has nuihin;: like the cajiaoily of ihi- iM)llex — 
there is no power of graaping in the .'■ole a.s there in in the {Ktlm. Motion of che 
toes forwara (unwanl) i-s artamon, in the op|Kjflitc direction m Jlexion. Thus, we 
eee that the sones of fonvafd movements prcseni.^ alternately flexion and extension 
— of the thijjh flexion, of the Ie([ extension, of the foot flexion, of the toes exten- 
sion ; and the hackwar<j movements are alternately, beginning with the thigh, 
extension and flexion. In the npl»er extremity the forward movementti, it will 
be ri'mcinbereil, are nil flexion. Tlie movementii of the Iik's sidewiso ari? abrlttf- 
tion timl iiiUlitrli'm with reference to a line running thnnigh thv normal long axis 
of the sevoEid digit uf thv foot, and not tin- third, a» it is in the hand. 



CLASsirrcATios of the MrscLEs of the Lower I-imk on thk Kahw 

OF THEIR PmSaPAL ACTION. 



Flexors. 

psoas magnus. 
Iliacus. 



Moving the Tbigb. 

KxtriuKir. 
Gluteus maximiiti. 



Abdudora. 

Tensor v-aginie feraoria. 
Olnteiis medius. 
Gluteus miaimue. 



A'l'litdrtre. 

Adductor magnus. 
Adductor long I IS. 
Adductor bifvij*. 
A(khii-liir gnicilitf. 
PcctincuK. 



Tntfrnal Rotaton. 
{The sonio in Uii- nbdnetor*,) 



Extfmal Rotators. 

Olitnnilor t^xti-niux. 
(iimdnitns fi-moria. 
Pyrifnrmi.H. 
GetnclluK superior. 
OhtniBtor iniernns. 
Gemellus inferior. 




MUSCLES MOVING THE THIGH. 

Moving the Xieg. 



303 



f/turor». 

SnrtoriuA. 

Bioops flexor cniriB. 

8(^111 i iiiomhraiiwus. 
Pupliteus. 



Quadri<.Tp« cxlvn^w crurb, comprising : 
Ib-ctm rcnK>ri.'<. 
Voittikri extftrniw. 
ViLitun interaus. 
Vastus intermediufi. 



FUmir%. 

Tibialis anterior. 



PermxruH tortiuv. 



UoTing the Foot. 



Extm»or». 



Tiliiulin p«Ml«rior. 
Ua:>tnK-n«miu.s. 

I 'lit n tarn. 
l*en>iioa-* loiig^. 
Peroneua brevis. 



Moving the Digits of the Foot. 

<Tliu«e MliiHted «itlir«lf in tli« fiio* are uidjcabxl bv ■ lUr.) 



FlexoTH. 

KI<-xor long:uH halliiois. 
•Floxiir lirevii* Imllucis. 
Fli'xor longua <!igitorum, 
•Fli'xor aowiHsnriuH. 
•Flexor brevirt digitonmi. 
•Flexor brevin muiiint digiti. 
•LumbricaUfr. 

•AbttiK'tor linlliici«. 
*Ab<IiK:tor iiiiniii)i dij^iti. 
*ltilcnMM;i (Jor««k-:<. 



Extensor propriiis liallucU. 
Extensor loitgiit; digitorun). 
'Ejctediwr brevU digiturum. 

'Adductor obliquuH hallncis. 
'Adductor tninfivcrsus haltticis. 
*]Dt<.To«<4.-i pbintartif. 



MUSCLES MOVBia THE THIGH. 



Flexors. 

Iliacu.s. 
Ahdwinn und Tnfemal Iinlator», 

Tensor vaginae fonioris. 
(ilutcus nioiliu^. 
Gluteus miniiiiua. 



Gluteiiit maxirous. 



A'MuHori, 

Adductor majcims. 
AiMuetor longiis. 
Adductor brevis. 
Adductor gracilis, 
PcctiiicHS- 



Obturator cxteriitis, 
Qiuulratii« fcmoris. 
Pvriformis. 



External JtiAtitom. 

Gemellus wiperior. 
Obturator iiilernus. 
Gemellus Inferior. 





THE MCSCLES. 



TiMjffJ-ont of thf. thigh arise partly fn>m tlie luiiiliur vt-rlfbra;, [Hirlly from 
iiim?r siirlact; of ilie fal* pelvU, and are iiirtcrtit] uimii the small tiMi-Iumier. 

The i/mat fjjrttmor arineii from tti« back part <it" ihfi hi]i-hoiii', .siu^i'uiii, uikI 
cowvx, and is inserted intu thf gliilcal rid-jif and the fascia lata. 

Tht tthiluetorn, which are also iiilcni'il rotatorx, arise fnmi llii- inner asjtei'l of 
tile hi|>-b(nie, and are iiiscru-d two irilo llic gri'at trochanter and one into the 
iicighlMring faseia lata. 

The ail'ludom ttrise from the hi|)-boiR' near ilie middle line of the body, and 
four of the five |ms-s onlward and downwanl with varying degrees of obliquity lo 
their insertion into the bsic-k jMirt of the shaft of the feninr, the fifth one going 
lielnw (he ktiec-joini Ut the n|>j>er (lart of the tibial shaft. They are to a con- 
sidonibie extent external rotatois. 

The rj'lminl mfidom nri.-w! partly from tlic ini^ide and partly from Iht untaidv 
of ilut b'lny |nK'is, niid are all inserted about tli<' iip]H'r cn<l of the femur. 

Fsoaa Magnus (Kig«. 34-i, ;i4t)), — "Tin- treat luiii niii-«ele," Synnuym, pnoos 
major. Situntitnt, in thi' hind wall of the alxh)nn-ii and the npjKT purt«f the tliigh. 




1 



Flu. 34i.~l'iHiU. inicui. *lwt tililn rnioi cxtcrniu iuiugIm. ilVttiitl 



Oriffin, the fnmt of the transverse pnx.-e^^M')' mid the nide of the lllKli4^^ of luniliar 
vertebra; and the side of the bodv of the liisl ihunirie, willi the ineliidcd inter- 
vcrtebnil ciirtilugvs. JJiiretion, down- and furwiird, and finally down- and back- 



QLVTEUS MAXJifLTi. 

ward. Inifrtion, the small troclumtor of tin- ft^ninr. A'Hojt, fle\ioD ami (^xUtiulI 
rotatiun ol' tbi- thigh. Xrrrm, th<- si'x-onil uihI tliiixl liimbur. 

nUciu (Ftp*. WS, 317). — "Ttiu iliivo miiwlc." Synont/m, iUaciiM inU-niiiif, 
•' iIm- iiitcrnul ilia*; iiiiiw^lf," SiliMltot; iii ilic iltiw* Utfsa aiicl llif ii|)]ht pari of 
the [high. Origin, thv upjier Iwo-thitfl* of tlie ili«c fo*N> uihI tin* ala of the 





PiR M6,— IVaMfnatnuiior rl|hltld*;nutlln«>nd Fio, MT.— Illaru* nf rlghl *Ue; niitllti* and >n*eh- 

•tuubniiiai.arou^ (K. B.Q.I m«nt-u«a<. (f. II 1).; 



aaRruni. Direction, dttwn- and ntitn-ard. Inaniion, i\u- Ipndou of tlie peoan 
iwi^niis, the front of the small trochanter aiwl tlw Hniall si]rfa<f below- it. Adiou, 
ticsiuu ami ositeriial rotation of the thigh. Xervf, the anterior crunil. 

The two )irf*etling miiwlei* — psoas an<l iliaca't— «rp sonietimes tivated an 
one miL-^ple, callr-d i7jo-i*«o««, 

Olatoua Maximue (Fipt. :t48, 349).— "The largest muwle of the buttwk." 
Situation, HiihiijtaniHiii!) iii thi* back of the hip and upjjer pall of the thigh, 
Orlf/in, thi* himl fourth of the iliiwr crest, the oilier smrfafe of the i!i«m Iwtween 
the crest an<l the superior gluteiil line, the hind i-urfiice of the lower two seg- 
meiit)« of the saerum and ui>per three of the coccyx, tlie great sae ro-ttcialic 
ligament, and the aponeiiro^iR of the erector epinie. l}irertioH, down- and ootwunl. 
Iimrrti'iH, the lower half to the gluteal ridge of the femur, the upper to (he fuivin 
latn. Afilou, extension and external rotation of the; thigh. Nerve, the inferior 
glui4>ul. 

» 



1 



306 



THE MUSCLES. 




Pm. StK— Glutent mkxlmua of rlgbt aide. (TMlut.) 



Fie, W^nluU'iin luaiimui at HithI M»: 
oulllne and nturliinviit-HrvKii. iK II. u.i 



Tensor Vaginx Femoris (Figs. 350, 3(i«). — " The tightener of the slienth of the 

thigh." Si/itoDi/m, ti'nsnr fiu-ida- latK, 
" the lighicner of the hrond fo«;i«." 
ifiitualioii, iu thi' front part of the outer 
as[>oct of ihe hip and thieh. Oriffin, 
the outer stu-faoe of the (rout part of 
the crest of the ilium. J>ir^ion, donn- 
vrard and KliRhtlv hackM^ard, In«er~ 
(ion, tlip fuM'ia lata several inches below 
the gnat tiXK-hantcr. Action, tighten- 
ing; of tlx' fux-ia hil;i, alxhictiou and 
iiiwiiitl rutiiiiiiii of tliiffli. ,Vcrfc, lh« 
.■tii[Hrior ghtti'iil. 

Oloteos UedlOB (Fipi. 351, 352).— 
"Thi- iiiirklli- hutUx-k-niiiwlc." Sihin- 
tifiii, in the oukt imrt of lln' hip from 
the iliae crest to ihi- trorhaiitiT major. 
Oriffin, lh<' external siirfacn of ihe 
ilium Ijotvreen the crest and the supe- 
rior an<i middle gluteal linen. Direc- 
tion, downward. Iviwrflon, the outer 
oarfiice of th*- trochanter major. .!(*- 
tion, alKhictioii of the thi^h. and, wlwn 
the thigh i« Hexed, inwartl rotation. 
AVrcc, Mk' snperior f^hilcHl. 

Oloteus Ulolmus (Fig». 353, 354).— 

" 'V\u' wnallcfil biittocK-niudck'." f^ilua~ 

flan, in ihr outer iiiirt of the hi]), from 

the fiiinl piirt of the crot lo lii<- gn.«t 

Origin, the external surface of ihc ilitim, betvrceii tJie middle and 




Fl0.aw,— TanuirnalniF friuarli' -rf rVhliMv: 
onUlueuiil MtM'hnivntHinvj. |K, ILOJ 



trochanter. 




_- J 



GLVTEUS Jf/XIAfVS. 



307 





Fid. 
blaH-tb. 



i of rlidil blp. rtoiiirtl ftom bc- 

muclniiu lUKlnK tni-n ciil itway. 



Fio. a51-nlmi>ti. mpdiai if 





rvi. XA— UhilNi iulitliuu> ut rtRhi (Idc iltarat.] 



Fio. S>i.~-GIuI«ui latnlmtu of 
tlKhl irtdo : outline and ittWliBWBt- 
■rwB. (P. n. (I.I 



nfcrinr ^liili'nl lines, 
^e grvat tnn-liiiDlcr. 
v&n\ mtiition, whi>n 




Dlirction. domi- and ouiward. /nwi^ioii, iho front cf 
.Wi'oK, alHliictioii i>l' iht-' thiKli, wlien it is extended : 
it i» fli-xi-d. JftTW, the sDpenor (gluteal. 



308 



THE MUSCLES. 




sJs- 



I 



Fie. SUi.—Adilui' U>n« macniui ■nill'nivlaof rlBhl nlde. |Ti*tiit.1 

Addactor Maenut(Figs. 355, .156. 373).— "The 
great inldiR-tur." SUtiathii, in th<> inntr side of 
the tliijjii. Orit/iii, the i^miis of tho os pubis, 
tbe niiuiiH uiitl mhcra-itv ot" the if^hiimi, liirei^ 
Hon, fi-om the ischiiil cuben^ily dowinvurd ; imni 
the pubic bmK- outward, fix>iii llie intcrmeclinle 
paPt« oblifliiely diiwnward jind (HitWHixi. Inaer- 
fion, tJie ffluUiid ridge, tlie inner lip of the linea 
a.-«|K-ru, tile intcriuil condvhir riitm- and the ad- 
diu'liirliiheirle. The Icnmriil mmohnienl irtbroki-'ii 
bv sevenil uribeit. .irlimi, iiddiiction and exter- 
nal rr>tuliiui c.f iht' tbif^li. The [wrt from th« 
bchial tiilxm^^ity i" extcii«ir. A'ktw*, the ublu- 
rator and tht^ pn-at wintit'. 

Adductor Longns (I'ip*. 357, 3-5«).— " Tlie 

hitijr addiieliir.'' S'lliiiitinu, in the iiuier :'ide of _ 

.1 '^ 1 . , .1 • • .1 11 ,■ I 1 • no. )M.— .Iddnctor munuicif riEhl 

the Iliiifti. (irHjiv, the IkkIv oI Ihe o« [Hibi.s %iat: ouiUnt snil Miaolnntnureu 

nejir thi- angle. Dh-ii-tiou, down-, cinl-, and '^' ^' °*' 

backward. iHteriion, tho inner lip of tht! lincu mtpent about tlie middle third 




ADDWTOli hOXOVS. 



309 



Ptn. («.— UukIm In lh« tIcIk Ihuli, ilF<*»t mm 
In ftmi. ftAtt rcmaral or tbo rmi» aoit uutorfiw. 
(Tartiil.t 



Pin. 1U^— Adductor lonem of rlahl ililv : uolllnf 
■uitatMehinDDt-attw. iV.V.fi.i 




THE MUSCL.IiS. 



^ 



Fia. 3S(i.— Adductor brerli of right aide : outline 
■nd Mtacbmenl-Breu, <F. H. O.) 



Fia. 380.— Adductor 
■Dd altacbmentareM. 



rrmcllliof rlitlitslde: oullloa 

y. H. G.) 



PECTIXEf^ 



311 



of the thigh. Aetion, adduction, flexion, and I'xlernal mlalioii of tlic llu|;li. 
yervf, the ubtiimtnr, 

Addnctor Brevis iFipsi. :','>o, S59). — "The short addiiPtor," .'^Huatiou, in ih<! 
inner mxt ii))po]' piirt of the thigh. Origin, the outer miriaec of the \ntAy und 
(leiwcnrtii^ niniii^ of the oe piibi)>. Direction, down-, out-, and backward. /it»fi^J 
tiiin, thv line fTx>m tlie sinalf trochanter to tlie tinea aspem and the ii[>{>er )Hirt of 
ihv linen lu^pi-ni. Adion, uddnction, flexion, and extern») rotation of the tlijg^h. 
Xrm-, ihi- lililiinitor. 

Adductor QncOiM (Fipi. 357, 360. 372).—" Thv slender tiddwctor." ■'HtHtilion, 
in th<- ttitiiT *idf of ihc ihi(;h near th*- wiriace. ftrit/in, thr iimcr nuirjrin of the 
OS [vuhU, thi- lower liiilf I'f the syniiihyi*, an*! the wlmk- leiiglh of thr inft'rior 
RUiiUA. I>irtftion, downwiinl, hchinil th<- inner cundylc of the fomnr. aii<l, belovr 
the knw, forwanl. InHertian, i\\f iipjHT jMirt of ihe inner utirfaw* of tiic lihia. 
AeiioH, additrlion of iltc (high ; nl.io, flexion and inwani notation of tlip leg. 
Neew, the iitiiiiTator. 

Ptctiaeoa (Ki^ '^^1, 'Wl). — "The niibic muscle." SUttatimi, l»etw<?en t)te 
pubic bone and the iipi»er, back jmrt of tlie thigh. Origin, the ileo-pwtineal line 





9m. Mt.— pgciiruui of TlKht ildc. outline ftod 
■tUrhmmt-ftRiu. (f. H. O.) 



riti. Ma.— Obliintor pitiimuK nf rlshl *\<lv-; ontllpe 



and the aiiHiice in fmnt of it. Direction, down-, oat-, an<i Irarkward. ftxnertion, 
the rotif^h line from the .small trooluinter to the linwi aitpcni. Arli&n, ad<li>ct)on, 



312 



THE MUSCLES, 



flexion, iiDtl i>iilwiird rotutiuti of tin; tliigli. Nnrvtn, lliP antprior crural ami M>nie- 
ttitii'S IIh- ubttiruiur. 

ObtUTfttor ExtemuB (Kif!:^. 'IJift, 3B2). — " The imltT olttnralor nuini-'k-,'' bo <nlIotl 
inim it-i <iri[;iti, Silunlinn, between the obtiiratiir region on the outer siirfaeo of 
tlic pt'lvis ami till- ilif^iliil for«<a ot" the IVniiir. I»ehimi nn<i beneath the hi|>-joint. 
Ori'jln, the imn-r hull' of the tuner aiirliire of the obtiiniUir meinbniuc, the aujoiii- 
iiifr -.iirfiiif?' of ihi- i«ibio Iwdy, and the piibic and ischial nirai. I>irectlo», oiit- 
waivt, then Ixii'kwam and npwar<!, dost- to the ifiider and hind eurfacei; of the 
cervix teimn'i,-'. Insertion, the bottom of the digital ro>«ii. Adiov, oiitn*anl 
mtatiiiii and adihtetion of the thigh. Nei-vt, the ohttinitor. 

QuftdratUB Pemoria (Fip. S5l, 853, 36.1).—" The square nniKiIe of iIk- thigh." 
i^ituation, between the ttibcr iachii and the nppcr ]inrt of thv shaft of the femitr. 




Fm. Ml— Qnailrmtua Ibmnrl* of right •iiii> ; uiKlltii- and iittii<<hmo<il«rcu. (F. H. O.) 



k 



Oriffin, the outer Itorder of die liiheroaitv of the iwhiutn. Dirfction, outwanl. 
hiKertion, the linea qiia<lriiti. ^le/<on, external potation and adduction of ihv thi{;h. 
Xerrr, from the i^erid plcxim. 

Pyrifonnis (Fijis 364, 365). — "The pi-ar-sliaped ninscle," SitiuUwn, hetwei-ii 
tile frtnit of tlif liJiid wall of the true iielvic ttiut tin- niipi-r end of the thigh. 
Orif/in, the ventral f^iirfaw of the §eoon<i, third, and fourth picei-t of the suc-ruin, 
belwet-n and outride of the anterior foraniiua, iitui the liimi honlir of the ilium 
Ik'Iow the inferior »piu<'. iJiiteihn, m-arly Imrizoiitiilly outward by Iht- grt^iit 
M^ro-M^iatio fonunon. InM-rtion, the fn>nt of the upper Iwnk-r of the fiwyt tro- 
chanter. AfCiun, when (he feiuiir w <'xtondc<l, I'XltTuul rotiition ; when it a 
flexol, iiI)duction. Xrrrr, from the saenil ph;xns. 

The obturator intenui)^ ami the Iwop'iuelli nre r'n iutiiiialely related that it 
uould he raiional to consider llu-ui im ii Mii<rle niiiMrle; but, iin they are always 
trvfited as Beparate orpui*, th*" conventional rule in hen* nli.*erved. 

(HmsUux Superior ( Fig. 36-1). — " The u])i«t little twin muscle." Sifuation, 
above the lenilon of the o)>turator intemuK. (trignt, the !>pine of the iMtbiutn. 
fHrtftion, oulwurd. Iimertion, llie front of llio inner surface of the great tn>- 



OBTVBATOR IXTEByCS, 



tUtaaie'X. Atiion, asastanr to tbe obturator int/'niiix. AVm, &om tlic $*cral 
pIcxiLi. 

Obtnnitor Intcrniu (Fig. 3fi6), — "The iiitvmiil >ibiiinitor nnwcU-," irfcrriiig to 





Fn^lU.— Unartaifr ilKtit lil|> vicwiiJ ftani b«blnd. UiC 



Ttn ViV- P) rifijnalii nf r1()il Mder outline 
mid ii,l(«(lmniii-iitTiu. Th» miurli' li ft|<t«- 
HDtKl 111 |«rt lu If Hcn Ibrouiih tht Ixjiiw. 



it» wrifpii. W/M/i/toN, lately within the pelvis on iia lateral w.-iM, iiitd piirtty in 
the ii[>[)er end of the thigh. Oriffin, the initcr tiiirikce of thv uhlurutor nioni- 




rin. MC— AMunUir liilrmu cif richt *lilc. TJic c^mcllBi kii^-rlof In ilma. biU Ikc luftftcd li mullr 
TcmurH. iTolot.) ' 

bmiH* ; a lar]gc im-giilar uiva hetween the nbtiiratnr rnrampo, ilio-pcctiiienl liiu<. 



314 



THE MUSCLES. 





Fid. ICT.'JiarUirtii* "( rifhtild*: oatliiu ami 
alWabmcDt-araas (f. II. O.J 



Fia. an.— SupcrilcU) mnsclM In franc hk of tha 
riflu thlfb- iTmru.} 



MUSCLES MO VIXG THE LEG. 



315 



Slid l\\<: frnuit inpm-Aoiittio foramen ; the from ami lower iiiartriiH nf llic nliliirator 
foRiiiittn. IMrteiioH, Iwckwanl to the hriM i^acn>-sciatir fiiramfii. ariitind ilie 
iaohium, and thtMioc outward, Jni^i-fion, the front |»rt of tln> uiihm- surfaw of die 
grvat troclianler, .4rfj<»i, iu extension of ih<? lliiph, external i-oiaiion ; in flexion 
of the tlilgli, alMlurtioii. Xerve, from tlie »-ari^i piexuii. 

G«moUiu Inferior (Fig. 364). — "llic lowi-r littlv twin nni«:lc." SiluaHon, 
below the tendon of ttw obturator inlcmus. Oritfin, the iip]K'r part of the 
tiilterosity of the i^^'hium. IHtrcthn, oulwarxl. hnvrlhn, the front of the inner 
Buriiiee of the great troehantcr. Acliofi, assistant tu lltv obtunitor intcniiifi. 
AVrtr, IVom the oacral plvxiu. 



MUSCLES MOVtNO THE LEO. 



Sartoriua. 

Biceps flexor cniris. 
S«tnitendiuoRtiif. 
Sen)imenil>runofiU8. 
Poplitens. 



Erlaufor. 

Quadricups exU-iisor crtiriii, comprising : 
Rectus femoris. 
Vastus extornus. 
Vastus inteniiis. 
Vastus in termed! us. 



Of the live Hexors thix-e arise from the ]«>lvis alone, one from the [>elvis and 
femur, and one fruin the fi-ninr alone. Thus, four of iheni itibw both the hip- 
and the knef-joints, «n<I heeiwne exieniwrs of tlie (high, wlii-n^ver Hexiun of luc 
leg is |>rcventi-d or fully lu'i-imiidi^hcd. 

One head of the niidti|di^- t-xteiisor arises frnni the pelvi.*, the othi'rs from the 
femur. Tin- iiari whieh flrft-ss*-!. iltn hip-joint a.- well as the knw-joint awtj* as a 
fli-xor of the thigh, when ext(-ui<ion is rompleteil or tht' knee is fix<-d. 

SaitoriuB ( Fip^ 367, 368, 372).— "The tailor's miwole," so railed fn.ni its 
uction, wliioh n.<v<iKt.'< in pi-odncing the cnMS-lt^ged position assiiriicd by tuilors In 
^llint; on the heneh. SHaalirnt, in the front and iniur ^iile of the liiif;li. bclween 
the ilium and tibia, (iriijin, the anterior .-.uperior iliae ipiue and pari of the 
notch below, Piredhit, downward an<l inwanl aero** the fivml of the thigh, 
then behind the inner condyle of the femur, and finally Inrwanl. Jniertirm, (he 
inner surface of the tibia, near the tubercle. Arlimi, flexion of the leg and thigh, 
and synchronous abduction of the thigh ; then outward rotation, jWrt-c, the 
anterior crural. 

Blcajw riexM Oraris (Figs. 369, 370, 372).— "The two-headwi flexor of 
the U-^." S'duiiltitii, in the biiek i)f the thigh, Ix-lwi-en the iwhiinn and fibidn. 
(yW»//ii, the long III lid : llic inner impression on the i«'hiiil luln-robity, in com- 
mon with the .'•emit nidi iio.>.ns ; th<' Khori hend : ihi? outer lip of the lima 
aspera and the ii])per two-thirds of the outer iiiiidyhir ridgt-. iHrtcHon, down- 
ward and a little outwanl. Iiwertion, the head of the fibula and (slightly) the 
outer tuljcrosity of the tibia. Its tendon fornix the outer hanudring. Aelion, 
flexion of the leg, and then i-xti>rnal i'<)tation ; aUn, from itn pelvic origin, exten- 
sion of the tliigh, .ViTiv, the great .seiatic 

SemiteDdinosna (Figs. ;J69, .171, 372).— "The half tendon muscle," Situation, 
in tile back of the thigh ton-ard the inner side, between the ischium and tibia. 
Origin, the inner impression of the ischial tuberosity, in common with the 
btCRpx. lyirrt^tirmt downward and a little inward. Itaertton, the upper [lart 
of the inner siirfiie« of the tibia. Action, flexion of the leg, and then luw.ird 
rotation ; also, fnim its peKHc origin, extension of the thigh. Xtrve, the great 
sciatic. 

Samimembnuiosua (Figs. 373, 374, 369).— "The half-mem brniic muscle." so 
callcl from the ]Hi;iiliar ilispusition of its tendons. HiUutHon, in the hind and 
inner part of the thigh, from the ischium to the tibia. Origin, the up[)er and 
outer liuiet of die i.'iehiul tnlKTosity. Dtrtrdon, downward and a little innnrd. 



L^ 



316 



THE MVSCLKS. 



Ji)Krii!fm. ii)a!ii1y the irrwivc on tlic biick of thf iatipr tiilx'n"«ily of tlii> lilti«; 
al>io. !i ri'tl('i.'li"ii iipwiinl iiml outwjinl lo tlir jxtftrriiir ligiinK-iii "f the Uu<^, nnd 
OIK' (Imvnwriril ;iiiil iniiwaiil to tlic fiiscia covcrinf; ihp p<j|)Iit<-iiT4. Airtion, fiexion 
of till.' IffT, iiiii! llii'ii iiiw'tinl rijtHtion; bIso, 
cxtonsiciii (if tlic (liijjh. Xrrrr, (lie gir-ftt 
M!mtit\ Till- IcndotiK of tlii.< miiHt/Ic, lli<^ 
.4<>iriit(tii<liiic>.-'iii' niid tlif f;ntrilis, foriti tho 
hiiu-r hnuiKtrUui, tlic ouUtr lieuig funned 
bv l!>t^ li'ii(iini of ilio hict-jt^i. 

Popliteust Figs. :175, :i75).— " Tlie ham 
taiiwle," Siliialion, behind the kneo-inint 
and in the upper [wrtof tho leg. Orir/in, 





Vui. m».-)1n>rlM In 111 « donuoi vT |h« rletit t'lu.sn.— BImu flexor criiria of riKhi iliW: ouUIn* 
tkltth, (Tonm.) >nc1 KilachnieM-aiBM. (V. U li.i 

th« outer KiiJf of the external witMlyK- uf l\w femur, within tin- capsule of tlie joint. 
IHrfption^ down- and inward. JiMrlion, thf triungiilar siirliter above the oblique 



MUSCLES MO VIXG THE LEG. 



317 




line of ihe tihiit. AfiioKy npxion ami inward mution of tlic l«g. Acnv, lliv 

internal popliit^. 

Quadriceps Gxtonsor Omris. — " Thp four-headwl extensor of the leg," Syitn- 

nym, quudriccim extensor femoric, " the 
four-Iieaded i-xteiii-ur of the thigh " — a 
mtsleurling nnniv oDiiKideit^ from the phvK- 
iologii-Jil jioiiit of view, Ihwiiiwc this init^lc 
doc not cxtfiid the iJiigh. 

(irnerul Dem-rlfition. — Three of the four 
liendn art'ie from the femur, one from \\w 
ilium. Karh wjrment is ileneribed as a 
st'parjite miir^ele, but all uiiiie in a common 
tendon of in&eriion, which is attached to 
the tul>crele of the llbia. The lovresl port 
of this tendon k ti^nully cslled the figii- 
Vifnliim uaUlfa; but, |>hilosu])liicully eon- 
sidered, it is tendon nitbi^T ihiui li^inicnt, 
and tiie iinlelln is only » -i-Miiii'iid bone 
develo|>e(l in il, cxa^^lly iiw ^nrli ix^eons 
furmatioii" niijviir in ihi^ ohort flexor leii- 
donx of the gn<il luc. The iliac |>art of 
tlic (|iia<lrici'|H i:« distinct from tin.- rest 
nwirly to ihi- )>atella ; luit (hi- oiIk'Ps are 
more or l&ss blended, and enclo«ie the tdiatl 




Tus. ni.— )<viniiciiilln«i» of right tUv: ouUlno 
and aiUirtiniviit aniti. (F. IL O.) 



Fiu. 17^— TIic InncT ituimrlng maMtcaat linlt 
[nurtlun. iTntul.t 



of the femur M «u4>h an extent an to leave hardly unylhiiif; of it uncovered 
excepting tlie liiiea luijK-ra. The four oomponent |nrt^ aro tlie roctiu fcmorU, 



318 



THE MUSCLES. 



vavtiiH oxUtiiili, vaAtuA internum, and va«tii» intermediiui, and they 
dcwrilirtl .-u'liitnitely. 

BectuB Feiiioris I Figf. 368, :)76).— " The straight mnivXe »f the th^.' 
i'tiin, niil)cul;inwni^, in the 
fniiil uf the ihijrli. Origin, 
one bead ; ihe anterior infe- 
rior iliac sjiino : tlio iitlitT 
head : the siirfiiw jnst alxivc 
the aoclabuhini. Dlrfiion, 
downward and >Ii<rhtly in- 
wurd. Iiivtrtiiiii, Ihi- iiji]K-r 




/' 



yt*. m^Mii-i'ln. 1(1 ilrrip la.rUiiii Vbi ^t,— iiVTntiiitinbniiixuit «f tight Kin. ST.i, — I'opltlvu* 

at rlgiii ihlili. uii> iwisl' >t4e ; aullliie uid Mucbmcbt'stwaf. {F. nf rlshi UJc ouituicand 



ttf •limum . . _ ,_ , 

Icndinnrai and hkki or thi- bicvp* II. 0.1 
haruiE Utn tvmoTnl- iTc*tut,t 



■tUclinH-nl.itrviU- (F. U. 



i 



borderof the patella. /Wton, exl«'ii!<ion ol' the It^; nlMi, rixni) Us iliac nrigiii, flight 
Aexion uf the thigh, when the leg i^ lixe<]. Xervr, the anterior rniral. 




MVSVLES MO VJSO THE LEG. 



Ft*. Sn--R4vtu( frnnrixif rtihtiM*; ODtllna 




Fio. ar;.— Mmnlff In ihe right thtKh. itawnd ftom 
la frant.afln nmiaTiil ot the ciittua uul tuitvritu. 
tTtttnt.) 



320 



THE MUSCLES. 




-^ 



V\a. S7tt.— VaituB EXturniiH of right tide ^ outline 
and itlac hrDciitarfHi. {F. H.li.) 



fio, STB— VbsIus Inleniui of right aide : outline 
and atlachmeut-areas. (F. H. (j.) 



jfrscLEs MO viyo the leg. 



321 



Vartw Exteniu (Figs. S77. 378, Mi).—" Th« outer immense mueclc." Sgm- 
fiy»i, viMtiisiutcnilie, "tlioliilenil iiDDiPDsc iuuhcIo." 
Skvntion, tlu> imXi-r part nf the ibi^li, mostly iia\*- 
enluni-oii.i. fh-igin, tin- vnturior intcrtroclmnU-ric 
lint-, the lua^tt ut' the frront IrtH^hnnlvr, ihr gliitvul 
ridge, itnd lh<> niilcr hj) of (he iiiu-n sviK'ni. IMnv- 
Uon, down- and forward, ihoii doviin'ard aud 
towanl. Intertion, ll>e iijifHT and outer iKirdorn 
of the intella. Actimt, exten-'ion of the It^. Nerrf, 
tlie anterior cm nil. 

TMtaa Int«rnua (Figs. 377, 37M, .'WS).— " The 
internal immeii^'e muscle.'* S^noiiiim, vastus niedi- 
vli!, "the iniHionae nmscle toward itie me<llau 

line." Sitttatitm, in the inner (sirt of the thigh, /\ ^\ \ \^ ^^ 
mwtly <^til>cutaiieoUh. Orif/'m, ilie lower part of 
the )t|>iml line of the femur, (he inner lip of the 
linea nspeni, and ihe internal eondvhir ridge; 
abo, Ihi- tetulon of the ad<luctor niagntir^. Dirrf' 
/i<Hi, down- and forwunl, then down- and oiitwiir<l. 
hweriioH, the inner and tiup<-r honler^i of ih* 
patella. v4efion, extension of the leg- jVmif, lh<> 
anterior ernral. 

V«sttt8 Intermedins (t-lgx. 380, .361).— "The 




Tm. 3Ni— V«Mlu iDlcriaeiliiu otrli^l lide. 
<T««ul) 



SI 



rtthl »i<Ie; «ii)ltna «nil •iiichnnrnl- 
»n*a. ir. a. O ( 



323 



TME MC.SCLES. 



intt-nncdialo immi!iii<<- muMk'," S»/noHifin, crunus, " tlit- leg inUBcle" — the coip- 
»iiin iinnio, liiit very liiiilry, Ix-chiusc it ini|ilio» kiciitioD in th« leg, whereas this 
U a musclfi altogi-tlicr in iJie thiffh. •Htwition, cIubi- to lliv (^haft of the femur. 
(/riffin, the upjipr two-iliiHs nf Ihc nnt^Tior jsiirl'mx- of tlic fimiir, the outer 
BUrliifie in front of ami hi-low llic oi-ifjin of i1k> vuftiii* fxli-rtiiiis. ami the lower 
half of the extfinial intprimi^ciiiar Ki'})Itim. IHm-ti'iii, mainly <lowiiuiir(]. Itieer- 
tion, the- upjK/r border of tla' jiatclla, Adiim, (-xlt-n.-^ioN itf the leg. Xcrvr, tliv 
anterior crurul, A narrow interval, extending downwunl fiiim n(«r Uw small 
iriHL'hanttr, separates- the vastus intcrmwiius from the ii)ternii.«. Ch»e to llw^ 
bon>' the intermcdius and externua are blended, but arc diittinct front caeh other 
el Mc where. 

E^lijclitl^ dialal to the lowest |>arl or the ori^iu of the ranluK intcrmudiiui a fc« Nmnll 
fasciculi ansc from ihv vrniral siirtiico of the leiuur nii<l [laiw ikiwiiwiml (u tli^ tiroxituftl 
pan of tlio nj'iiovinl mrmbniiu! iif ilic kiicc-joint- Tlicy arc iisunlly spukcn of as the sob* 
crureuii, but would better be i^nllud muieului nrtteulim* jTrnii, " iho knee-joint tniisclo." 



4 
I 



HUSOLES MOVING THE WHOLE FOOT. 



Flfxora. 
Tibialis anterior. 



Peroiieu« lertiiia. 



(On 111* 

utii*> aid*.) 



(CTilnl 



(On Iht 

DUt«r Hda,) 



Exfmnon. 
Tibialis- posterior. 

iGairtrocoemias. 
Solcus. 
I'lnnliiriit, 
( Peroneus longiis. 
( Peroueiw brcvis. 



All of th<*e mu^^Ics find inscrlioii in the foot, and all «ri«e entirely in the 
leg, excepting two, whieli liiive their origin upon the thigh, and, niin* they eixws 
both knee- mid anlcle-jniiit;<, an- Hexom of the leg, when the foot i» Gxetl or fully 
exteiiiliii. 

The exten>ors are iihuy' nnmeron.-* and jjowerful than the flexo!>i, the group 
which iKJcnpies the centriil jjosiiion in the leg acting upon the foot puivly as 
exten)«or». The inner and outer muwlefi respeetlvely turn the foot inwani and 
outward in addition to their work of flexion and extension. 

Tibi&tis Anterior (Figs. 'A^'l, 3*ta). — "The anterior tibial mnsrle." Smongm 
and eonimoner name, tibialiii nnticuri. SHitnfimi, in the I'mnt part of the leg ami 
inner side of the foot. Ori//!n, the external tulwnwily nml iip|jer two-thirds of 
the outer surface of the tibia, an<l the fnuit of the (■orrc^pi nidi tig and adjacent 
portion of the interotiseons nienibntiie. Dinrlian, downwtiixl iinti iiiuiiixl. Ihmt- 
(ioit, the inner surface of the internal i-uneifonti and tin- iiriiximiil end of the first 
nietnlar»il. A'-lhn. flexion of ilie fool, elevation of it.4 inner border, and a<lduv- 
tlixi iif its iliKtal enil, Xm-r, the anterior tilHal. 

Peroneus .T«rtius ( Figs. .'^82, 381). — " Tlic thini fihnlar mn^cle." SitiKitiini, 
in the front of the leg ;iiiii dmsnm of the foot. Origin, the lower fourth of tlw 
anterior nnrfaiu- of the filmhi, and the eorrt^r.ponding and atljaeent [wirtion of \\\v 
ioteroHticons inenibrane. IHrectifm, downward, then forward and outward. Inser- 
tion, the upper mirfare of tlie base of the fifth metatarsal. Action, flexion of the 
foot, elevation of its outer border, and aljdnetion of iti^ distal end. It is ttu'epiir- 
nble at its origin from the extensor lon^rns digitorum. Xertr, the anterior tibial. 

Tibialis Pofltorior (Figs. ;{«o, :W(i, :t1)4, a98).— "The hind tibial muscle," 
t<iin'.'rii/m and commoner name, tibialis posticus. .>'i(wtfi<ni, deep in the back part 
of the leg anil inner ]«irt of the foot. Origin, the hind surface of the interOftseoiw 
nienihnnic'. llie niiiier half of the contiguous jMirtton of (he tibia, and the inner 
.MM'tiuvcif tlielibuia. /'(Vr'-(ion,<lown»var<l«nd iuwnrd lulhe luiek of the inner mal- 
leolus, then forw«rd. Imfrtion, the tubenwity of the ii^-aphoid, with ofli>hoot« to 



MUSCLES MOVING THE WHOLE FOOT. '. 

th(> three i^iineUbrm, the caboid, the bases nf the bccoimI, tliiixl. and fourth meta- 
tarsal, and the imtileiitaciititm tali. A<Hot\, extrtiKiun of tlw fool, eleviition uf its 

inner )>ortler, and iidduetion of it^ di»tul end. Utrv^ 
the iHwterior tibial. 

QatttTocnemiiu (Fi),r<. :J87, »88, 391).— "Tho Iw-lU- 
<if-rlip-li^ (or calf) muscle.' Station, ^iijierficiitl in 
tlie back of the leg. Oriffin, tin? outer head : the 
outer side of the external «>nd_vlc of the femur, and 
llie surface just above ; the inwrbead : the upijcr part 
of the inner condrle, and tlte loner eud of ine ndge 
above. Oirciiio)), downward. Iitfiertiou, the hind part 
of the tuberosity of the ealcaiivum, in common with the 




Pi'i. Ml— UiiKlvt tn the riKbi 
1*C. viewed iroiD Id Itonl. (Tulat) 



fi.i. »a— Tilji»U» nnierlor o* rUht 
iililit: nuUiiiu and aUavliuicnl«Rai. 
(F. II. ft I 



no. 3U.— htoneo* ivrUiu iifrlcht 
■lilu : uiKliiiKuiiilattat^hini-at'iuuiii. 



Mileiu. Aiiion, extension of the foot : uW, when the ankle-joint in fixed, flesi<. 
of the leg. .Vtrrc, llic intermil poplittsil. 



324 



THE MUSCLES, 



I 



\ 



,, ^OLGUll 



Fto, :!ik^.— Mlvui and pluiurli of rliht tide, 
risttnt.} 



Vic. ivf, — ¥olcui or rich! ■Id! : oulUiw lad 
■lUchiacBt-kitu. If, K, U-i 



XmCLES JfOVING THE WHOLE FOOT. 



325 



llWKWStC (.!>*. 



OA! 



lUS' 






line uid •IMtliiuettl-unt. iV. ILH.i 




Flo. Ml.->Tlt>iiiUi (HMltrlar at Tifht ilde. ^Tmiui.i 



'mitinaudattMnniMKH!TJWM««fm 
nitiKlg l« ruMMHiMd u If Men thwoin (H 

bonw, (P.hTo.) 



MUSCLES MOVIXG TUB WHOLE FOOT. 



327 



Solenz (Figs. 3«9-3yn.— "The solf-fisti miircic," m mllwl fmm its »liin>e. 
Hifiwnifiri, giD^trociK-miiii^ iiit4^'rnuis " tlic mU-nuil iK-lly-Jif-tlio-k'jt mawlp." -Silua- 
tion, in llie buck pun of tti« leg, in fmiit of llio gustrociif uiiii». Origin^ the bcfld 




Vta. 3Vl-~>IUM?li» In tliv tinier glilv uf iIkIiI \rii nu'l ilonuui of l<^i<. <T<ltDt.) 

and tipper thini of the hind surface i)f the fibula, and the oWiqiie line Bn<I intor- 
nal liordfrof the tibia to iIk' uiuldk- of its »hiiA. Dirrttton, downwiinl and a 



328 



THE MVSVLES. 



liltie backwiirti. In«rrt!on, tlic liiiid part of the ttilwrosity of the calcant-um, in 
piimniuii ivilh the giutrucm-miii^. Action, extension of the foot. *V<rr«, the 
interiml {K>pUteul and [K>!fti-rii>r tibiiil. 

The j^iwtnKriiviiiius ami sulciii^ un- 8omptime!« anil not fnncifullv considered ait 
a Binjlle miuiele under the name of tricfjj* mra:, " the thrce-lieadeil niUM^Ie of the 
calf "^ — the former rnrnwhiiii' two head)-, and the hitter, one. The common tendon 
is called frudo ralnmrim, "the lieel tendon," Jind alwi more com ni only, trndo 
jWliifl'", " Ihi- tendon of Achilh-.H," in nllimioii to the leKeudury heni, whinie only 
vulncrublc j>art wus hiit heel. Thin tciidoa is (hv lurgesl in the body, is abuut six 





Tm. WX— Wtotivui loiiKua «f ricbt iMe : auUloo Pm. MK- Pcndcdi brovlt of riitht tide : oatlUe aDd 
•ad andchTDcnt-BniB. tK. U. U.) MUtrhmcDi-tivu. |P. U. oj 

inelii^ 'oi'g. narrowest at the level of the atikle-joinl, and r("«tivo« miiwuhir 
fihn.-,-! almost to it** insertion. 

P!»Bt»ri« ( Fij;. ."589), — '* The Bale-of-the-fi>ot nmscle," rcfiirrinffioitii occasional 
in?<ertiiiii into tin- plantar tascin. Situation, in i\n- Ijaek of the leg between the 
gnat rot 'nemiuii andsoIeUB, (Origin, the ridgt- aliove the external <x»n(!yle of the 



MCSCLES MOVING 




WHOLE FOOT. 



329 






Fid. aM.— MukIm In ihodMiiIarCTof ihadnnum nf tha 



tMe: outline and Bluebaiciit arta*. The 
■niiwli- in rebnaviiMil » mhii ttuut Iha (r«nl 
ttiRiiigh Ihvlxint*. IP. II <-.i 



330 

femur. Direiilon, <lowiiward and inward. Iiinfriion, the calcaiieuni at the inner 
side of the tenda AehilH^'. Action, txtensioii of tlie foot and Scxion of tire 1^, 
Na-re, tile internal ponliteal. 

PereMUB Longfua (Fips. 391, 392, 394. 3St^).— " Tlic long fibular ninwlc." 
Sifii'ilinii. in the outer siilu of the leg and \\\c wlr "f the fimt. (h-igtn, (h*- .niter 
tiilnT"*ity of the tibifi, the head und ii])|>er two-thirds nf thi- iniii-r Kurfaev nf the 
tihiilii. Dii-fll'iii, downward to tlie httfk of the outer timlh'iiUiit, forward on the 
onli^r Mile iif tiic rtilaini-nni, through the unmvo of ihe Miboid, inwnnt and 
forward aerow the ia>\r:, Iwfrllnu, the Imihc of the liivt iiictiitar^l and the internal 
cuneiform. Aftiou, t'^ttviwun of tin- fo<ii, ehtvalion of il)» miter edge, and aMno- 
tion of its <li.*tjd I'nd. .Vn-rv. tho mn.'<euh>-irnlaneon-t of the external [wnditeal, 

Peroneiu Brevla (Fiir*. .tJll. 393, :W5, 398).— ''The fhort fihular innscle." 
SHiialioii, in llie niitt-r side of the lea and foot, Orif/in, iht- lower two-thinU of 
the outer ^nrfaiv of the tihnln. Jiirection, downward to behind the external 
mulleobi.-, then forward and a little downwanl. hutn-fion, the onter side of the 
tuberosity of the lifth metatarsal. Action, extension of the foot, elevation of its 
(inter eddo. and abdnetion of Its diKtuI end. AVrrr, the iniiwnliM-nlunetnif of the 
cxtorniil |H)])litea]. 



MUSCLES MOVma THE DIGITS OF THE FOOT. 



Flexor longiii< halhieis. 
'Flexor brcvis halliiei^. 
Flexor longus digilorum. 
•Flcxwr a(wi-jwnrin». 
*FIexor brcvisdipitonmi. 
•Klexor hrevin minimi digid. 
*Lumbricali». 



(TlicBio BiuiiiI'.'J tiuiti'ly in lln- foiil ntv jndknlcd bv u Mill'. I 

FlfXfiin. Kxlrnttorit, 

ExteiL-ior proiirui? hiilbids. 

Extensor longtui digitonim. 

*Extenaor brevis di^tonim. 



Abdudort. 
•Alxhietor hallucbi. 

•AMiiotor minimi digit!. 
•Intoro.*nei dorsalee. 



Additeian. 

"Addnetor obIi(|niis hallueis. 
"Adiluctor trans vei-su> lialhieis. 

*Interossei plantares. 



In studying 'he museles moving the digit;- of llie foot it Is unneees=arj' to 
pbee in a group by themselves thoKe which act iip<in the great toe, as was done in 
the eaiie of those of the thumb, for the reawon that the firfl nieti)Inr!^it Imne K as 
fixed as it,'' fotir fellows, and do<* not iicmiit tlie degree and kind of movvnifnt 
whifli are m> lunrkeil a featuiv of iligital aelion in the IiiiikI. 

All but fonr of the twenty-four memlHT:< of thi* givaip urc «itunte<l entirely 
in the foot. 

n*xor Longm HaUucis (Figs. 394, 39.'). .39S).— " The long tiexor of the gr.-ut 
toe." Si/i'oui/m, flexor loiigiis iiollieis pedis, " the long flexor of the thumb of 
the foot.*' Slhialloi), deep in tlie back of the leg on the outer side nn<l in the 
sole. Origin, the lower Iwo-thirtb of the bind liurtaee of the fibnia. and a little of 
the inteiYH'i^eon^ membrane IkOow, IHrrrtion, downward and inwani, Ijehind the 
inner malleolus, benenth the ^^-iiT^tentaenlnm tali, then forward and inward in the 

sole. Iiufi-lii'ti, the under >iirfa f the base of the last phalanx of the first 

digit. Action, flexion of the hu-tt phalanx of the great toe. AVrrr, the posterior 
tibial. 

Flexor BreviB HiOluciii (Figs. 396, 391»).— " The rihori Hexor of the gitMil toe," 



MCSCLKS MOJTJfG THE DIGITS OF THE FOOT. 



ArHonnn, flt-xor brfvi* mllicw [x-ilii*, " llie sliurt flexor of the tliiimb of llie foin." 
Sdvudmn, in t)H' lliini luyi-r of the inui<otes 
of ihi- «ik' on tin- iiitw-r sultr.' Origin, the 
iiiiHT lK>ri!i'p iiiid imdiT surfaoi- of ili*; ciil>oid, 
urid the cum-ifiinu ti-ixion of iIk' lihial!.^ pos- 
terior. Wi-rtrffV/w, forirard and inwant. /tuvr- 
tioH, one (l'"' inner) lemlon : the inner AAc of 
the base of the first phalnnx of the preal toe 
on the plantar aspect. fuse«l with the siixluctor ; 
the other tendon : the outer ^dc- of tla- «un>c 
bone, t-ymnii-lricnl with the inner tvnduti, and 
conjoined with the adductor. Vmv\\ nf tlw-wt ton- 
dons endo^'^ u MfTSinx ml hiiiu'.aiid iHttwiH-n tht'm 
liv» the tvlidon of the hing Hexor of the gnuit toe. 
^■r^jon, flexion of the whole of the great toe. 
A'crce, the internal ])l'int3r. 

Flexor Longus Disitorum (Fig». :)fl4, .t!)7, 



a 



uie 



Fio. IK.— MuK'lv* la lliv UiliO Uycr 
u( lit" rl|fl>l will'. Tliw biiUT of Uin Rvsev 
l<n>vi> inliilnil iIIkHI biu brvu remoivd 



898).— "Tit.- U'lig rtexf.r of the digits" of tlie 
fiv>t, meaning the fonr j-mall toes. Synonym, 
flexor perforans di);itoruni jicdii-, " the perforat- 
ing flexor of the digits of the fool," referring 
to the pasfiage ofiti; tendons of imKTtion through 
the corresponding tendouN of the flexor bixrvis 
digitornm. Situatioji, deep in the liack of th« 
leg on tile inner side, and in thtr wile. (JrUjin, 
tin- middle iwo-rminiis of tlii- innor part of tht- 
hind Miirfne>e of the tihin. OirrHion, do\\'nward 
behind the inner iualleohis,th«n forv^iird and out- 
wnnl into the wote. In^frtion, by four tendons, 
eaeh into the \)AM' of a third jiliahinx on the 
plantar surlaee. Thi- tiinlivided tendon U super- 
hcial to that of the flexor lungn^ halliieis, Ewch 
digital tendon i)erfom(cs the eorre)H}Hjuding ten- 
don of the flexitr brevis, just as the flexor pro- 
fundus perforates the flexor publimis in the liand. Action, flexion of the lost 
pliuluuges of the four Ismail toes. iVVrrf, the posterior tibial. 

Plexor Accesurius (Fig. 399). — "The adjunct flexor," thi^ being ajwii^taiit to 
the flexor longiis digilorum. Synonynia, flexor ae^;•e»«Jriu^ digitorutu poiis and 
qiiadr.itus jilantie, " tlie sonare muscle of the sole." S'luntion, in the hitid |iart 
of the w-e^nil uineeular layer "f the sole, Oriyii\, the caleuneiim- — one head 
b«!ing mtaebcil to the inner surface, the other to the outer suriiee in front of the 
external luliervle, DirrtHon, forward, titurrficm, the outer (hind) bonier iind 
upjH-r MiHaw? of IIm? tf-mlon of the flexor longus digitoruni. Aeti'm, flexion of 
the four small t<K'*. tl iiIko brings the line of action of the flexor loiigiifi digito> 
nun into the hiug axis of the f<)o1, .Wnv. the external plantar. 

Flexor Br«TiB Dlgitorum | I-"ig. 40Oi, — " The j^hort, llexi>r of tbe digits," mean- 
ing the four small toc^;. Synonym, flexor perforalUH digiiorum jh>disi. " tlie jrt- 
fonil^Hl flexor of the digitit of the tool," Sit'iafloti, in tlie first mn.'^nhir laver 
of the JKile, midway between it?" sidi*. Origin, the front of the inner tnliei-cle 
of the ealeanenm. Diret4ion, forward. Itufrlion, by four tendons into the sides 
of the sfH^ml phalanges of the four small toes on their plantar as]>eet. Each 
tendon is pertnmted opposite tbe first jihaLiux by the corresponding tendon of 
the long flexor. Action, flexion of the second |)htilangi.-« of tne four small toc«. 
Servt, the internal plant:ir. 

Flexor Brevis Minimi Digiti Pedis (Fig. 399). — "The sliort flexor of the lea*t 

' Tlie lavitrf nf |>l*ntiir miiu !>'> .in iiuuil- iv| rmni ili»*urfiu<e uf thv>Kil« upward, ni thcT' oecnt 



332 



THE MUSCLES. 



ilipit of tJie foot" — I. I*,, of the little toe. Sifnonpm, flexor <lipili ijiiiiiti lirt-vte, 
" tlie short flexor of the fifVh Jigit." Situation, in ihe third mii'-fuhir hiyer of iho 

BoIe on its outer Iwrdcr. Orir/m, the lln(ier^■urfac« 
of tile base of the fifth inetiitiirnsih DircrHon, 
forwjird, Inerfium, the outer isidc i>i the ba^e of 
the (ir>it phnhinx of the fifth Hk- on ite plantar 
aniM-ft. Arli'iJi, flexi'ni of the iiftli toe. iSmy, 
tlic i-xtt-riuil [ilnnlnr. 

Lnmbricales iKij;. 39!)).— "Tho oinh-worm 
iiiiisi'K-s," from tlipir fancied reiu>'inblance to cont- 
niun angle-wornis {tumbrici). Eaeh bt a liimbri- 
oali-i. yum/ier, four. Situation, in the fore part 
of t!ie second miiHcular layer of the sole, Onifin, 
from tlie dig;iial tendons of the flexor loii^uA uip- 
torum, the first from the inner mnt^in of the iiini-r 
tendon, and ea<!h of the oihers fnim the twa ton- 
dons between whicJ] it lies. IHeedion, foruird to 
the inner side of the four small toes. IngrHton, 
the extensor t4-ndon on the doi-simi of the first 




\ 




i 



J j.f "";•.'"' "''■'.''*'" '*;"«°' dlsltonim of . /». a».-Tem!onii In Ihe lieht vole iTcMuLI 

Tnt mnipic ImprricnlHl n>iien<n fr-mi In 
Aonl Ibroatti (liv biiiin. if no i 

{ihnhnx. Aefion, first, flexion of iIm- fipit ithnlnnges ; second, extension of tho 

i*co»d luid lliini iibsdiinKcs. .V.ffrj", for the inner one, the internal (daniar; 
for the others, thr ■■xtvrnul plantar. 



MUSCLES MOVIXG THE DIGITS OF THE FOOT. 



333 



EitoMor Proprios H»Uiid« (Fip*. 3R2, 401, 402).— "The proper exienwr of 
the great toe-." .y_vii'»if/"i*, cxtcnxir loiigiii* ImlliieU; exteii.4or proprius po]licis, J 
extensor longu* pollii-i* iR'iii^. " Prr>j>riu» " U prelerahle to " loiigu.u " m immingl 
this muscle, Ik-cjuim- vxi«-iiiii>ii of tin- gri-at toe is jrartly eflecied ihrcmgh th<ii 
toner teiuIoD of \\w exteii!K>r brevis digiu>ru[ii, a muscle not special (proprius) to 





Kill. W.~nri[iriiir<«in'li»au<l liunbricalc* 
of riRbt fbot. a»l<il-> 



PiQ, (ML— MiuolMOf lhv*UMrHrlBll>TMOfUM 
riihtAiDI. |T«tlut.) 



thU digit, hilt a\H> coiKMrnKf] iii extending three other toes. Situation, in tlie front 
of tin; 1*11 «(kI ilor^tiiii of the focit, Orif/tn. the middle two-fourths of tlie iiuterior 
NitrfiMv iif thi- fibiihi mid itdjiuN-iit iwirt of tlie ititcrosteoiw memhnmv. Dirrction, 
diiwiiwanl, through ihi- nniiiiliir lignmcrit, then forwiinl. itnvjini, uiid A Hltle 
dowiivrard. Jn*erli(iit, the doiNiini of the IwM-of tin- Wt ptmliiiix of tJie hallux. 
,-lr(/<j(i, exIeu!«toii of great toe. AVnv, the Anterior tihiiil. 

Extensor Loiwus Digitorum (Figs. 3fi2, 403). — " The long exteiiwr of the 
digit-, " meaiiing the four nnuill toes. Situation, in thi> fr«jiil of the Ii^ and dor- 
Bura of the foot, Orii/in, the external tHberowity of the tibiji, the luiid nnd two- 
thirds of the anterior surfuce of the fihtila, and a little of the iippi-r jiari of tlie 
inti?roweous membrane. Dii'eelion. downward through the nnmilar ligament, 
then forwiinl iind a little downward, Intfiiion, hv a tendon for each of the 
wnttll tow. Kach tendon divides into three psirts, of whleh the middle is utluelied 
ut tJic Immt of lite R-cond plitiliinx on il» dorsul lufpeet, the latcml part;' uniting 
nnd finding tittuchment »t the bni>e of the Itift phulnnx. At-titm, oxtemion of 
the four ^mail Uk-v. Xfrrf, the anlerinr tibial. 

Extensor Brevla DUitorum iFig». 404, 401). — "The ^liort extensor of tbe 




334 



THE MCSCLES. 



digits" (it the foot, fiitualion, in the tlorsum of the foot. Origin, tho front of 
iht upper and outer surface of the calcaneum. DireeHon, forward, and » littlv 
inward and downvrard. Imrrfion, W four tendons: the first at the base of th« 




Wv). Wl'— Muicln in tho ontcr 4lilc of tiglii Ipg boi] lionuni of Gwl. (TMnl.! 



first phalanx of the great toi* on its dorsal tt^jwct ; the others on the outer Ikorders 
of iIk' long extensor tendons of the ■rtuikI, third, and fourth toes respectively. 



MVSCLeS MOVING THE DIGITS OF THE FOOT. 



A<^ion, of il»c ftist tendon : cxf(rn»iinn uf the first f Jinlanx of the grmt Xt», an<l i-1if^it 
»d(IiH*lir>ti;of th«r cith4-r»:n>.'>ii4r»iKf to the loti^ C\t«nHor. .lYrt'rc, the anieriar tibial. 
It slmiild be observed that this iiiiiscle does not act upon .JuHt the same dijc'xUi 
iL* dw,-* llio long extensor. The extenMtr brevU is inserted into the great toe, but 
not into the littic ; the extewwr longiis int^i lh« litth- toe, but not into tJie great. 





Fio. «I3.— Exuminr propilui haltiivtiof lisbt tide; Pro, 4<B.— KxUOMTlOllttMdbMoninior rtltbtildG^ 
DutllDF nnd aiUi-hmi'iil^KOi. (F. B- O-i ttlUlnv uicl lUlimhinenl ■ijM. (F. EL nj 

Abductor HaUucia (Figs. 4U(), 401).— "Tlic nlMlnctor of thi- grrat toe." 
SifHortjfm, abdiitvtor |)iilli(vi> pedis, "the ab<lii<'Ior iif tbtt thumb of the fooL" 
Sitnodon, in the lirst miiM-ular layer of the .-w^)!!- nn the inner nide. Origin, the 
inner Inberele of the wilcmitiTiin, Dii-ttiton, forward and a lillle inward. Inaer- 
liiiH, the inner side of the base of the first phalanx of the great too, cvinjoincd 
witli the irnier head of the flexor brevi!^ ballucis. A<ii9it, abduedon aiHl flexion 
of tht" great toi-. iVcn'f. the inleriinl plantar. 

AMuctor Hinlml DiglU Pediit (Figs. -KH), 404).— "Tht- abdtictor of the smallvtit 
dij^i of the fiM.t." Siinmnim, idMlnctor digili (piinti, " the abdiu-tor of IIm; fifth 
digit." l^ittuiiion, ill the lirsl »ui:^iilar liiyer of the iwlc on the outer i»idt*- 



336 



THE MUSCLES. 



Oriffin, both tnlxTcl*!* of t)w wilcaiifiim. IHreetion, forward and a liltic t>ut¥,-ar(1. 
IiuurtioH, the outer »\t\v of tlwr Imnc of tlie first phalanx of the little toe, in com- 
mon witli tin- short Hcxiir iif thnt toe. AHi<ni, alxUiction of the fifth dipit. Aotr, 
the externul jilHittiir. 

Interossei Dorsalea Pedis (Fig. 4<>5|, — "The danail iiiteros»ei>ti» niiiwlt-x i»f tho 
fruit." .Vtmi/t'-r, four. SUitotioii, one in eueh of thv fonr "[wecs liclweu the 
meutumal hrrnes. Origin, each from tlie udjaeent sid^.-s of twn metntHi-xiil hones. 

Direciion, forw-aixl. ftivrrtioiif llie Iwscjs nf ihe first 
phalanges, as follows : the Hri<l to the inner side of 
the 8eeond tw, tUv xccoiid to the outer side of the 
second t<>e, the thini to thi' outer iiide of the thil-d 
toe, tJic fourth to the outer *ide of tlie fourth toe ; 

X 




lOustH Dons* 

IHTtKOI*IOU> 

intiKOMtoum 




■CCONO BOBIJ 
riRIT OOKIAl 

iHTCBoaaiou* 



rin. lot— Rxb'iiti'ir bti'vln di^- 
torum of rlgbl toot. O'rrlM.) 



Tta. Mk— lniFro»uil 4«M|]M Of liiht riwt. The line u U 
■ ■iHjurtlosftnsde. iTcatUl.) 



Iba[ ttvm whlrli i 



t 



also, each to the extensor tendon of the eor responding toe. Action t each 
alKhietfi from h line drawn through the long axis of the «?cond toe. Those 
acting on the weond to<r .in- alternate) V nhdnctors and udduetore: when one of 
them lid" alxhietwl the toe, theotlior restores it toils attiludt of rerf by adduction. 
Th<- dor>dil intorfissi'i also flex the first phalanges, andafterwan) vxt«ud the second 
mid ihiril. .Voir, the external plantar. 

Adductor Obtiquiia Hallucis I Fig. 40f>). — "The obli(|ue adduefor of the great 
toe." Syi}(m_ifm, adductor poIHcis [»odis, "the addnclorof the thumb of the loot." 
Sitiuition. in the fore and middle part of the third muscular layer of the .wle. 
Origin, the proximal end*; of the second, third, and fourth metatnr^ls. IHrrr- 
fion, forward and inward. Inmrtion, the outer side of the base of the first 
phalanx of the great toe. in common with the adductor transver^us and the 
outer hn\<\ of the flexor lin-vis hnllueis. Action, adduction and flexion of the 
gn-jil Imi-. A'ivt, (hi- i-\li'i'i]]il |iliinfar. 

Adductor Tranaversas Hallucis (Fig. 4<)(»i, — "The tnmsveree adductor of the 
ereat toe," f^ymmijin, IrnnsverHiis pedt.s, " ilie trnnsver!^' muwie of tJic foot." 
Siiuation, iu the thir<l mu.seutar layer of the sole, ncros8 the distal end of the 
metatarsus. On'ifin, the lower metatarso-phahmgeal ligamentx of the outer three 
toes and the transverae metatarsal ligament. Direethit, transversely inward. 



If CYCLES MOV/XG TUB DIGITS OF THE FOOT. 



337 



Iniffrtlmt, the Xwe uf tlip fin^t pbalnnx of tlic ^rvax. fm-, coiijointlv wilii tlic u^lfliw- 

tor itiiliqiiii;: iiu<l tliv uiiUT lii-ud of the flcxiir brfvis. Adinu, MililiKrlioti of IImj 

gn-iit luf, .V'T'-, the exlvriml plunliir. 

Interotsei Pluit»rea (Fij;. i{)7). — " Tltc pluiitur intC'TXRvviMitt imipcles." dumber, 

thn-p. Sihiatitni, the iftjconil, third, urul fwurtli !>|ia«r>t Ix-lwcftn iho ni«talanai Itoiiea, 

on the j>la»tur atipect. (/riffin, th« iniu-r ana 
uiidt^r surfaces of metatarsal bones, as follows: 
the first on the tliml \mne, tlie second on ttic 
fourth, (he third on t]ie Aflb. Dirtetion, forwunl. 
Jnecrtion, each on the iDUcr side of (he Inum of 
th« firfct phaUmx of the correnpomling toe nnd 




rt»»T PUHTlfl 
■HTIROSSCOUS 




- THtMD PLJtKYItlt 
INItllOBtlOWB 
• (COna ■k.lMTIlIt 

inTtnoBseoutt 



TVi. «(Ml— Hiucin In iha Ibird layoror 

lh«ri|btMlS. tTolUt.] 



rio. 40T.— InWroMCl plnntufM i>f rlrhl Itoot. 
that III uliirh aiMiifUi'ii )> iimilu. iTiuIuM 



ThB line u !■ ' 




its extenmr tondon. ^Ic^iVm, ndiluetion ton'an) the se<^nd t<H>; hIthi, flexion of 
the first plialnnge^, nnd nlWwtml exleii^ion of the itecond iiml third ptuUange?. 
Nerve, the external plantar. 

The inten)»«Hm.a mimilen, the abductor and the two adduclor^ of the hallux, 
and the iilKhietor minimi di^iti are iiliysiolocically U|>on the same plane, lorniiiifr 
a Rronp «'ho«' mcnilwrr |tr<«iiK'e iho UittTiiI movements of the tot-ji. The great 
toe hiix one muscle (iibdiiet<ir hallueifi) iii-^'Tted on the inner side of the base of 
thu fircl phaliinx, and two lulductors on the np|>"«ilo eide of the same bone ; <^oh 
of (hu oilier Xiwf hiw two muscles similarly atlarhed. They arc arranged as fol- 
lows, the iniwr niii^clc in each ca^e iH-inR named first : the wcond t^K- has the first 
dorsal interos.«i'oiii> and the scconti dorsid int<-r(H<e<ini< ; the thini Uk hiw the first 
plantar inU-m^-u-im^ nnd the tliirri duTHid ; Ihi- fourth too hns the )^x-i>nd jilantar 
mleriin.-1-ous nnd the fourth don>]tl ; the liflh Im- htis IJii- lliinl pliuilar iiit<'ros»oonK 
and the atxlneinr minimi di^iti. The Inferosscti inscrtt-d n|Hiii Ihe six'ond toe iiro 
alternately alKiiietoiN and adductors; the other don^l interojwei are nlu'nv* 
abductor>4, and all of the plantar interossei are addnctorn, the middle line of the 
swond toe wlion at rest (leing the line from and to which movements are re<^koned. 
Compare this arrangement with that of the homologous parts in the upper limb. 

Plow PftTToi (I-'iic. 34S).— "Tiie liiile IdJii-tuiuiL'lo " is smnll, flul. iacuuHUut. of irKf«- 
origin, miu.aiul io froRt of the petias mnKniis. Moftt frrgucDlly it arises from ilic bodiea of 



338 



THE MUSCLES. 



llie luwest thonicio nn<] tbe hij^hoet iiimW vertcbrm aiid the diK Wvre^n them, tubmlyto 
fihorl, ami ila lonK irniion. hli'n'icil with tlir iliiu- fascia, in inscrto'l iiilii tlic ilio-iicctincal Mni' 
nuniKi. It U II t<Miiior of the iliiti^ fiuv^iii. 

JWUSCI.KS WHICH MOVK THK I^lWKIt LiMH, OK(li;i>Kt> AIX'OHlUXft 'n» 'I'llKIK 

IjIK'ATIO.N. 

In Ihe Pdrui and Upper l*art of thf Thigh. 



Psotta niagnuH. 



Oliileu^ mnximiitt. 
(iliitc-ii» meiiiiirt. 
Glut^uH mininitis. 



/« tlif, ftetfltin of Ihe liuHitik. 



Oliliiraliir intcrmw. 
ticiiirlhin iiifcriiT. 
({iiatiralii^ fenirtris. 



TeDHor vaginie feiuoris. 
Sartorius. 



HemimcmbrniinsuH. 

Adductor inut^niig. 
Adductor luiigiia. 



Vfttitui^ iiit4^rri»». 
Vastus intcmiediii!!. 



l$inc|M B«xor vruri*. 



(r t^if. I 

PoiilitcuM. 1 



I 



Pvrilormia. 
Obliinitor cxternuii. 
GeniGlluB sujierior. 

Jh Uie Front of thf Thit/h. 
KecLus feinuriti. 
Vatitus exteniiis. 

/« the Knek of the ThUjh. 
Still i tend i I KiHue. 

In the Mmtd Part of fhr Th'u/lu 

A<ldu(;tijr Ijrt'viit. Pcotineus. 

Adiliirtor gnicili.i. 

In thf. Front itf the fjiy. 
Tibialis antorior. Kxtoiwor propriu!* IulHucIs. 

KxiciHor liiMgiiN difritonini. IVromuii ti'rtiu:^ 

/h /At! Oufrr Part of the Imj. 
Peroneua longti^. Peroiieutt brcns. 

In the liiwk of the l^'ff, 

GastrcxTDL-miiiB. ) i, ^ ■ i 

n. {HuperfifUU riCXiir IOII({li!* Iialllli"lji. \^tferp 

Pla^itoriw I fl"''*"/*- K\"^^ lnufriisdifiiilrtrwm. {group. 

' TibialiH jioaterior. ) 

In thf: Dtrrtnan, 1/ ihe Foot. 
ExtenMrtp hrpvi-i dijjitoriiin. 

In thf Hotf. of ihe Foot. 

t Fimt (mprr- Flexor accwjHiriiis. ISrcourf 

,, , . - - ?"|-"^'-''."' 1' fei(i/W«ucr. Ijiindirkiilvit. i (nva; 

Aniiiiolfir miiinni diyiti. )■'''' / j 

Flfcor liif-vis halltRi^<. 

Adductor ()l)li<iiiiis linllncii;. I Thinl 

Adductor transvereus tiallucls. ( faj/n-. 

yiexor brevU minimi digiti. 

The miicclffl of llio lowur limb having been considered in proiips according 
to their tiinction and acconling to their situation, it is iidviwible for the student 
now to make other e]a38ii)cation» of theiu, in order to view them from as iimnj- 

Kiitts an por«ible, aiid thim obtain a n)or» intimate aeqnatntnnce with tbe Ktd)ject. 
■t him amtiiKC them according to ihe bonm which ihey ronnrvi, as those eonnccting 
the hip-lwne with the femur, witli the tibia, with the fibiilii : the retniir with th« 
vcrtrbnil cobimti. with the tibia, wilh tbe fibnin, witb the niliiitniim ; ibe tibiii 
widi tarwd biinc!*, wilb metatsirsid Iwnes, with phidiinp-s ; and mi on. 'I'hen let bim 
i>tudv ibcni in Ihrir irliiltojui (o Ihrir imrntYliitIr nrii/hhrirf, its shown bv jiliini' jeetionH 
miule nl dilleretit b'velo. Some of tlK> fignre^ iu tbe ebii|iter mi Uie iirlerict) will 
boof ^riTHt »iiHiKlancein lhi» matter. WhMi bubuii Wrned the di'M!ri|>tiv<> anatomy 
of the nerv<>!«, be would do well to n>vicw bin niynlt^v, ami K"^"!' ^'l '*f 'I** mu»- 
cIcM on the basis of ihrlr nfri'<'-tiup/>lif. Other methoas may be a<l()pted — tbe mora 
Uie better for tbe student's improvement; but tbotie su^ested aro among t)ie best. 



AVbietor hallnci.-<. 
Kli'xor lirevi* digitonim. 



InterusHJ plantareii. \Fourth 

Inter()«sci donsilles ]>ediii. J Inj/er, 



THE MUSCLES OF THE BACK. 



THE MUSCLES OF THE TRUNK. 

TImm will ho conwidorpd in fhrw? grmuw, a.« follows : 

A. 'I'hi- nitiscW of the (Kick, iticlwiing tlwse m tJie ctorsum of th« oectc. 
H. The mUHcIes of the nhdomm, 
C The iDUHoles of tlic thorax. 

THE HTTSCLES OF THE BAOE, 

inclDdins the Dorsum of tlie Neck. 

The musclos sit»atctl in (lie hut^k of 0,w Initik nn<l ix^ck iirc arranged in a 
niimbcr of KH>n|iw, which arc- n.^iially tlworihMl a» layer**, nithoiigh lb« lamination 
of IImwc nuK^t ili-vply hK'aUn) i.-< »i»l diHtiiici. 

Ttw first, or miptrrfifuii tiii/rr, coiiijiri.-'itif; tlic Intjioziiui and liitJi^iniU!;, and the 
»fi?miil /niffr, niaclv up of thv lovuiitr xitpuhi; and tlt<- two rhninlioidoi, huve ulivady 
been det^rihed in eonnection with tlie iniii<ele.t of the upper liinb, lui tlicy func- 
tionally belong in that doss. 

HoscIm in the Third La^^er of the Back. 

SerraliLt |>0Aterior .■"UiHTim-. SploniiM (vapiti.-*. 

Sermtiis [HKiterior inli-rior, Spleniiu cervJci.-*. 




Tm. «^.—ltme\m la Uie tblnt lifer or ttic lack. Tbc Kmnu pntwrlor Infulor l> alioini In ilir nnt 
OgQre. fTMlnLI k 

Serratua Posterfor'Lrfertot (Fifj. 4*)S). — "Tlic upper, hind, siw-toothcd muBcle." 
Si/nonitm, wrratHs poHticu* i»ii{)crior. Silualion, lit the base of the neck and np|)er 
part of the thorax, nearly eovon^d by tlio levator «eapulic and rhoniboidci. Ori- 



340 



THE MUSCLES. 



gin, the lower pari nf the nnpe lipampnt, and tlip 
two or tbn-e iipiMr ilnirat-ic vcrtebne. Direction, 
down- and outwarcl, Jnieriion, llie second, tliird, 
fourth, and fifth ribs beyond their angles. Adion, 
elevation of the ribs of its insertion. Xcrrca, tijc 
second and lliin! inlen.oftals, 

SerratuB Posterior Inferior (Fig. 40«). — "Tlie 
lower, Iiind, siw-loothi'd iiitiscic," t<i/iirmifjn, .si-r- 
rutiw ii(i!>tiini.s inlV'rIor. SitiuUion, tW ii|)|K'r loin 
and lower thoraeic n.'jrioiis. Origin, thv spines 
of the lower two timracio mwl iip|»cr two or three 
hinibar vertebra.'. Dirfciiuu, outward and niiwanl. 
Jvserlion, the lower boi'ders oi' the lower fonr or 
five ribs, bevond the line of the eostal angles. 
Action: it dniws the lower ribs backward and 
downward. Xfrvji, ihe ti-iilb and t-levcnth inter- 
costal. 

Splenitis 0&pltl8( Fig. 408). — "Tliestnijv.^haiK-*! 
niii^rli: of the hi'iul." Siluation, in tin- back of tlie 



i<pines of the last oerx'ieal and 





SPINAS 



P 



(he back and OD Uiuiluimui of Ui> •boulder. 

(Tcdut.) 




t*», (Traiut.l 



THE MVSCLES OF THE BACK. 



341 



neck, in fmnt "f ihff trapextiis. Origin, the lower two-thir«l(i of ihe naw ligfltiicnl, 
aiiil tlio s|>iin>:* <»f the »cventh cervical awl first and second thoracic vfrtebr». 
IHrfiion, ii]>u-unl an*) outward. Ineertion, the mastoid procps* of the ti-intwnil, 
anil the Mi|ii-ri<ir I'lirved liiic of the o«?(;iiiital. Action, extension of tlic li«id. and 
iU n>ratiun I>i tin? (iide on which the muscle lies. A'c?-«, external bnmchf)' of tlie 
doi^al priiuan- division!^ of the middle cervical, 

SplenioB C«rvicis t Fi(t. 4tW), — " The strap-^hnfied nm-H-lc nf iW m-ck." Sifit- 
oni/m, >plcniu6 colli. Sibta/ion, in the back of the neck, in froiil of iho Imitexiii^. 
Oriffin, the spines of the third, fourth, and fifth thonioio vertehr*. I>irffiioH, 
upward, omward, and forwanl. Iiigt-riioii, the hind tnbon-k'H of the tJansvpriM? 
proeea<M?s of the np(>er two, three, or fonr errvinil vertelinc. Ari'on, extension 
of the neck, and its rotiititm to the side on which the iniiwU' Ii<w. \erveg, exter- 
nal branches of the dnrwil )>ritiiarv divisions of ihi- loucr rervical. 

Mascles id the Fourth Layer of the Back. 

T\w /wiiilt lager i* furnied by the erector spitia; (the erector of the spine — 
that i!«, llie miwch- which exii-mhi it). It coiu^tituto^ the jireater part of the long, 
roiind<'<l nui-v, which nins [lamllel to the series of vcrli-hntl spinous processes, 
and project so Gir backward that, when a view is taken of tlic i-iiiirc bai.-k, (he 
bones seem to be sunk in a valley between two uiuiiuiU, insttad oi' prutruJiug 
«onspicnoiiB]\% as in the skeleton. 

The Erector Spins (Fij^. 4U1) is a compound masele, beginning lielow in a 
single ma!^, but soon diviiliiig into three portions, which {miss npwaivl and end at 
different liciirht*, tliat nearest the middle tine (piinj; no further than the iip|K>r 
part of the (horux, the oiitennu.st pjis^ini; well into the neik, and tlie midiUe 
naichinff to tlie ba!*e of ihi- •■knli. The second and third of ihcnedn not pi>x'ced 
to ihi'ir rifpoctivc di^iioittion^ iinint<Tnip(<'dl_v, but by n series of vtc|w, each 
makinjET three. The nrningi'inent snggejitw the simile of sealing a cliff: a* Uie 
inii'^ie climbs up the li;i<'k, it d.x'* not relinqtii.«h one fwithold until it lias estab- 
li.diecl a new one — it lako a fn-fh fjrip before it lets go the old ; and, as a remilt, 
there is not inert-Iy coniinnitv of wlrncliin', but overlapping, one >ie};nient bt^n- 
nine back ( someiimei (ar bai'ki of tin* ending of the se^jinent below it. Th« 
varioa>* portions are deseribwl lu-* sejiarale miLioles, TJh' name erector «j)inic 
properlv includes them all ; but it i^ often used in a rttstricted »pni>e to designate 
the ondivi<led niass from which these prolongations ari«', 

Scltrme. of the Erei-tor >^ia«e. 

Outer <Iii'i«ion : 

Ilio-costalis. 

Acoessoriii.* ad ilioHMistalem. 
Cervical 114 aseendens. 



Erector spitue- 



Miiiille ilirimon : 



Lunp;i]>tsimiifi dcMV* 

TRinsveiHiliB oe^^'■ci8. 
Trachelo-mastoideus. 



Inner diriiii'm : 

Spinalis dor«i, 

TTie Erector Spina arises from the lowest two or three thoracic .ind all of the 
Iiimlxtr and sacral ^piiKts, the transverse proeeeaes of scvend lower thomeie ver- 
tebne, the lower and Iwek part of the sacrum, and the hind fifth of the iliae 
crest, Frnm this beginning come the thrw divLnions — tin* outer, the middle, 
and the inner. 

The outor diviaon starts off jiwt below the last rib as tlie ifio-eogtalis (Fig. 
410), to called from ita connecting the ilium with certain hIm. It is ahro known 




342 



THE MVSCLEH. 



V 



m 






^ J 



Pi« m.-Gtwlor iplB«. ThP ouWr »>;rl« In piilloil 
Oiltvud. ITwtut.f 



Fin. tlv.— Ecvri'Tr t'.>\%\n TTio middle turi*) A 




THE MUSCLES OF THE HACK. 



343 



IIh* (Wrrii-Ititii1«ili«, im it Ix-giii.i iit tin- iqicml ri-jpim »ml niiis )o tlip liimlKir. It 
tn iiiM^rt^l into tl)o lou4T nix or si-vch HIm hI tlii^ir aiif^ki', nr in ll)c lintr of th(- vok- 
liil uiiglo.1. Frniii ttit- iuirm- riKi, & Irilte b>wnr<i Lh<' tiiiiMIc lim- iVmn tlioKC 
]>oint8 of in.-^-rtion, Apriu^ the aeefxaori\i» ad itio-*^»lat>^m (Vig. 411), " (liu adjunct 
to llic ilio-o<MtalU," which jiaswfi up and U uiserted into tht! upper lux rib^ (at tlio 
angles of thmn below the tirst, ancf on timt on« near tho tiihorde), and lite Inins- 
verso process of tho vertebra prominena. On the Coat or five rilti above tlwise 
from wbirh tho actvswrm- nri-H.'s, a liltle mesisUy from its lino of costal in.-^rlion, 
are the i)uiiit>% of orii^^in of the crrricalut <uetndau (Fig, 411), " the ascen^iitg Deck 
mitftele,' which thiLs sustnin^ it n-lntioii to fhc iicc»'!r«roriu» like (hat of the latter to 
the ilio-custalis. It in inserted iiilo the IranevcrM- proeuMKM of the fourth, GAh, 
nnd KJxth cervical vertcbne. Tbii>c three tniDwh'it — the ilio-cOMtuliK, iKuyMxrius, 
and (rer^'iralis !w«:inh'ii:< — ^^re in iippciimiice am! in cfli'ol pniclically oiif. 

Tlif mtddlfl and Im^'-'it division nf thi- eit'ctor Kpinie lic^tiLv us tho lnng»»fMm\ta 
tlomi (Figs. 410-412), " the 1i>n)r)-.st niti.->irh- of the buck." It is inHcrlitl into lh« 
triiii''Vi'rw- jiriuH-;iM---> of all thi,* thonieii' nnil the aowswry prm-^wieji of Ihi- liiiiiiiar 
verUtbiw^Hud into niont oftho ril>.'< betwtini the tnbiTrh-.'' Hndan);h's. lis n|i(v»r(l 
prolnttgalioii id eallul tniniwi-rxitlU i-et-uicut (I'^S^- 41*1— tl2), a naiut- whi<-h «-I<-ni 
to the attachnienu of the mu.tcle to transverse processes. It arLsee from tlw 
transverse pr\K*sses of fn>nt four to six upper (hftraeie vertebra-, internally to llw 
insertions of the lon^issimus, and is insi-ried inio the transverse processes of cer- 
vical vertebne from the seeond to the sixth. The Iii^it sejpnent of this division is 
tlK trache&i-mastoiiieiiji {VigA. 411-413), " the neck -uiiis toil) muscle," so called from 
its situation and insertion. It arises from the tntusversc processes of from four 
to six upjier ihoruL-ic vertebrie with t)ic transversuUs cervicin, iiiid aW from tho 
arlieulnr prueestfes of the lower three or four cervical ; and it is iit»crted into tile 
miKtotd process of tlie temporal. 

Th«- third anil siniillest dtvUioa !« nearest tlw mt-dian line, and is ^vcn otT 
fntni the main muss of the erector above the middle of the thorax. It is ciilled the 
Hpinitlii (lorgi ( Fig. 410\ " the spinal muscle of the bsiek," with reference to its 
bony atlnclimentK. It is a ounlintintiou of that iwrttun of tlio common mn»» 
which urit^w fn>m the liimbur iiiid thoracic »pifK-^ iin<l !» in^rtcd into the »pii>ra 
of a variable number of vertebne in the upper thonicii'- region. 

The el!ir<^t of lliis arnmg^'ment is snch that ihr eri'etion of the verlebrnl 
eioluinn in ai-i^oiiipli^lxHl, not its it would hi' by ii uiiisih- whirh hml no attneh- 
ments betw<-(M) llu- sacriuu and cranium, but by :i (vinlimious succession of con- 
tractions from one small division of the column to another only a short distance 
away. Thus, a variety of actions is effected, and strength and steadiness of raove- 
ment imiired. 

The ner\-ous supply of the entire series comes through the dorsal primary 
branchcK of tlio spinal nerves. 




Muscles is the Fifth Qroap of the Back. 

Thej^^ wru!s of mueclt^ lies in front of the erector spins. They are all 
chaiacteriz«1 by the direction of their fibres, which is from below upward and 
iiiwanl. Nearly all of the points of origin are on transverse proccssc" of ver- 
tebrw. and most of tlK- iuh^ertions are on spinous process:*, the fibres piissing fnnii 
» transverse prtweM to the spinous process of the fourth, fifth, or pixth vt-rlebra 
abov*. Tbiy ari; the following: 

Oiinplexns. _ _Multifiduif, 

Hemispinnliri ccrviri^. Ri^talom>. 

Sen) is pi lud is dorsi, 
Oomplexns (Fip<. 4^•i, 411), "the intricate muscle," sometimes is called mnti- 
npiiialU r/tfiiHit, but without gtjod n>as<in ; lor the term " semLspinalis" in con- 
nection with otiK'r muscles is used to signify that one attnchment is U[)on spinous 
processes of vertebre. It arises frnm the transverse proccKsea of the up[x^r i*ix 



344 



THK Jft-ACLfCS. 



or seven thurant^ verlHiru; iiixl the last cervical, and from tW unlniljir |ircK-i-»ipe 
of cervifjit vcrteltne fn>iii \\iv thin] tu the sixth. It is iiiscrtcil inlu tlir 

(K-(-i]iitiii Ixmc, cm till' mesial mrl nf llu- »urrucf 
Ix-lAVi-t'ii tlic curved lines. Tlii' ixulimi nt-iinvt 
(III- iniililli- liiip i(i (Htnicwliai detaclii-ii, mill linit 
II li'iulirioiis iii!KTi|>tioii alxint half unv of ilx 
Ii'n};th, nil fliwuiint uf which it h often ivckone<l 
wt a x-iHiRiU! musoli>, the biventer nrrrtCM. Tho 
eMiiiplexiifi extend8 the licjid, drutviii^ it to ouc 
side. It6 iierve-^iip[>Iy is from M'verat U|>pcr 
eti'vifal nerves. 

Semispinalu ceiricia i Fig. 41'2), tiiv niiiiu; 
mi-iitiinn " the muscle of the uei:k, one exlri-mity 
ijf which iis iiltHvhcd to ^^pinoiis processes," ari^ws 
friini tlu' tniiisvcrsc proccsscB of the upper five 
or six thoracic vertebra-, nnd h Jiiwrtcd into 
the spinous pnH'iwocf^ iifccrvicHi from the second 
to the tilUi. It extends ihc m-ek. ami mtate* it 
to the opfiosito side. Its iiervi-s lire hraiiehea 
from the lower eervii'Hl and iip]ier thoiiieiv. 

Semispinalis dorst (l''i^. 412), " the niiiscleof 
the back, one end of which is attaehi-d to 
spinous processes," iiriw-s tVom the transverse 
proceiMics of thuraeic venebne from the sixth 
to the tenth, and is inserted into ihe spinous 
ini«i\*«eis of the Wt two cervit^al and of tlie 
ii|i[ier four, tivc, or six thonicic vcrtcbnp. Ita 
ju'IiieifMil iii-tioii is extension of the h>wcr cer\'i- 
nil nnd iip]H'r thunieie rejfions. it is i^upplied 
by Ihonieic ^iiimd nerves, 
Mu]tifldaB(Fig. 412)," the ninny ■cleft niiiiMle,"<ie<'iipies thcRrealer part of th« 
(Tillt-r bi-ide the vertebral opines from the Nieniin to the iixif^. Its fibres puss 
from some piirt (nsiuilly ii piiH'cjw) (if ctnc vertebra to ihe spinous processes of 
several vertwtnc hIkivc it, (jenerally the sisvtnil, third, nnd fmirlh. Il arise" fn>m 
the )n>^H>ve on the buck of the .-^enim, the manimillnry proees.-es In the hindiur 
repion. the ttTinsverse in the thoracic rejrion, and the articular of the lower four 
rerviojil verlehne, ami i.-« insertifi into all the spinoiw pro<iesse-s of the true ver- 
tehnc. It exiemls, heii<ls sidi-nise, ami rotates to [he oppo.-ile side the !<{Mnnl 
column. The pa*terior branches of the "pinal nerves supply it. 

Rotatorea, rotators of the *'pi'io, lie covered in hy the miiliiruliis, and are by 
Dome regarded as pari of it. They are constant only in the thoracic region, are 
eleven in nnniher, and each jwissea octween the tmnsversc process of one vertebra 
and the Taniinn of the next above. Tliey pnMliice n>tation of the spine to the 
op)K)site side, ami also bend it l»iek\var<l and Tfiilcwise. Their nerves are the 
thoracic. 

In the cervical and lumbar regions »n: found u scries of small mnsclcs, culled 
hidfKfihio/rii, which puss from oik- fpinou.'* proeew to the next tibovc ; umi another 
«;ri(tti, the itilrvlrrinMrfrmlei (iiilfrtriintn^erKoriijt whit'l) eonneet one Transverse pro- 
cess with the next above. 
ID it8 lateral flexion. 




pipius. 



ll^i.-Tiiw'lidu-inuMId Mid com- 



The former assLsts in exten.'iioii of tlic spine, the latter 



SUBOCriPITAL Mu»CI,BS. 



Reo.tutt capitia posterior major. 
Rectus capitis jiosterior minor. 



Ohliqiius capitiR inferior. 
Ohttqnus capitis superior. 



Rectus C&pitja Posterior Major (Fig. 412). — The name means lilerallr "the 
greater straight hind muAcle of the bead." It arises from the spine of tfie axin, 



THE MVSVLKS OF THE AUDOMES. 



345 



R^xttiM nbdaininii). 
PvniiiiiiliilU. 



(Jiiadratufl liioibortiiu. 



jWfnnn upw«ru umi oiiivv^itl, unJ i^ iuiM^rtetl iulo tlit! oulc-r jKirt of \\w infrrior 
curved line of rlti; oo^ipiuil, aiiJ iJte surface iu front of il, Ii rxlt-ad^i iIk- licad, 
ami rolutcs il i» ili« saim; sid"/. The mi/ioccij>iW n«t^ Mipfdifs il*aiid ull the 
otJurs '•>{ tJii* t;r>"i|». 

B«ctiu Capitis Posterior Minor (l-'ig. 412), " thn eniallcr flniic'lil litild iuim-K- 
of tiiL- Iiwid," iiri-i"'!* DM Uir rulii-R-lo of (he ixistcrior urcli of tlip lUliiB, runs upHiinf 
lUid (viilwiiri), iind \* iii.->i-rli>il iiilo ihc iiint't [iiti'l. of tin- itif<'rior curved line- of ilic 
on'i|iil.-ii :iii<i liii':ity-ti in fniiit of i). It i-xti-niU lli'' hi':iil. 

Obliqunft Cftpitts Inferior ' Kig. 412), " tin- liivtcr til>rujiii- nitucl« of lh« licjul," 
ariM-Jt fn>m (liu N]>itii- nf tlic nxi.-', giM'.* iijiwiii'd ttiul onluiinl, and !.-• iii.tcrted iitio 
lli« tmiiKViTiK; pruocM of (lie allfti*. lid [inii('i|iii1 ni'iion Ik lo rolalc l)u> atlas to 
iho snniv iilde. 

ObUquua Oapltl« Saperlor (Fig. 412), " tlx- iijiiht iiIiHi|nf- iiui.-^Io of iho licad," 
arises from iln- tmii'^viDo* iiroouv. nf tin? atlas, ja^^i^ u])™^^!, backward, and 
inward, and is ni.-iert<>d into tlio ^iirtaiH- Ix-liiiid the inferior curved lin« of the 
occipital. It extends the head. 

Tlio threo-sided space enclosed by the rectus major and the two obliqiii k tl»e 
VHhoeeipilai tritiM/te, 

THE MUSCLES OF THE ABDOMEN. 

Oi>lii]nti« exIcrntiK tibiloniinif. Trans verbal is. 

Obliqiiii>t inlcniiiM ubdomiiiU. 

Of these masclc* the rectus and nyramidulis an- in front, the iinadratus in 
behind, and the contRHclile {Mirtion ol the obliipius cxli-i'uu:*, iibli(|iiiu itilernUs, 
and trausversalis arc at the ;«iilc, tlii-ir libroiM part ex- 
tending forwanl ami inward to the niudian Uiic of ibc 
belly. 

B«etiu Abdominis ( Pi;;. 414). — " The !itnit;;hl mus- 
cle of tile aluiomiri." SHitnHim, in tin- front wall of 
the belly, Oritf'm, the piibio crej*t an<i wyinpliyis, tlic 
tendon fnini the latter point i-oiniiifj from the oppo^iite 
*ide iiml <;rriis-«iai» ilK I'l-lhiw. Dirrrtimi, Lip*varii, i-urv- 
iuf; u'ilh convexitv forward, oorreAjiondin^ with lln- 
cotiioiir of the Iwlly. Iiutfirtion, the fifth, sixth, and 
seventli oontal eartilayi'*. Si^veral tendinous intorsec- 
Cioos {infrriffionai ti-wUni-tr or litiftn Ir'i/mviTim), usually 
not occupyinj; the wliuli- thickness of the mnsi'le, cross 
it, generally <ine at the levil of the ensifonn apjicndix, 
ono at thai of the navel, one U'tween the-c. and ol'lcn 
one l>rh»w. The •heath of the mtisclu iii formed by the 
t4^ndon)f of the laleml mnsclen. (Sec below,) Aeli'm, 
depn-.uion yf liic tlionix, and compri'*sion of the ab- 
doinitiitl vi««»'ni. .Vcj-rcjf, the lower interi-iistal and the 
ilio-hv|Mi;ipi.i|ric. 

The three lateral niusele.s constitute three nearly 
co-cxtcnsivc layers, and their broad tendons of iniwr- 
tion (eulhil "aponeurase.-i "). seijanite at tirst, he*'ome 
blended alon^ u slightly erirved. nearly vertical line 
(ealh-d Hitfi imnilimari); " the half-intHwi line") just at 
the outer wlge of the n-etiis. Tins eonibined leixfon 
then spli|.« vertically inti> laniiriie of eipial thiekiiev, 
which Mcjuinite and embniee llie reetur*, one piinfi in 
front, the other iK-hind, and tiuallv niei-l again at the 

median line, where ih.-y fuse with 'eai-h other and with .'iSi. "frlSTJiV""'"" "' '"^^ 
the corresponding structures of the opimsile siih>, niak- 

iri(r a atronji, periwndieular, fibrous band called /iMca nffin, "the white line," 
which runs from cnsiform pi-oetvss above to syniphysis pubis Iwlow. The inclu- 




— Kwnin nMnmlnli 




a46 



THE MUSCLES. 



myn uf llic n>ctus Ity th«»(» tendons ohiaine, however, only in the up|>er thir* 
f'oiirlli.'* of its oxlont ; liie londoiiH all |>a»8 in front of the muHcIc in tlio lowe 
qimrtcr, leaving tlio corrps]>onding hind suriiicc free. 

Pyramidalis (Fig. 414). — "The pyrumidnl muBclc." It arises from the front 
(if the or4 j)tihi>t, runs up in the iih<.>ath of the rectus a short distance, and is in- 
.tertcd inm ihe linea allw. It is very inconwtnnt in presence, «!«•, iind )^ht>))c. It 
is adjum-t to the reetils. Its nerves are the elcvciitli iirid twelfth thonieie and tlip 
ilin-hv|j'Pg;i.-.inc. 

Obliquus Externns Abdominu (Kik- 4!o). — "The oxtenml nbliqne nni7>ol<.' of 
the abdomen." Hilualion, aui>erfieial, in the fide and frnnt widiw of thi- liidljr. 

OHffin, the outer snrfacc of ihc lower eiglit rilta, 
Oirccflon, downward in the liind part; downward, 
forward, and inward i-I«'wh<'n". Imirrlioii, the front 
half <if (he onter lip "f llir iiine ercsl, ihi- jinhie spine 
and rrest, ihi- ilio-pcelin<al line, the front of the syni- 
jihysis, and the linea nllia. Thr |Miints of origin make 
n snw-iooih(^d line, the upjier dijritations interloekinji 
with similar points of the sen-atus matins, the lower 




Kbdomtali of right tids. t. tniul.j 




Fto. tit.— KncnuU abilomliMi ring of rlghl rid*. (Tmiu(.} 



with those of the lutis^imiix. The tendon of insertion is a broad shc>et, wliioh 
passea to the mid-line, and there fuses with its fi-l!ow opposite nod with the ten- 
dons of the intt-mal obtiijue and tninsverssilit^. Tlic part of the tendon exlend- 
inji from the anterior sii|MTii)r JHae i^piiie to the pnbie i^pinc is thicker than the 
re.-il, and hn (.tl^e is ciirli-d backward, forming a narrow .ihi'lf. Tliis ibick |Kirt is 
th« inf/altuit lif/itmeiil, c.omnionlv ealh'd t'onjiarr's li)£unii-iil. From its pnbic end 
extemis iiackward to tho ncigldmrinfj extremity of iht! ilio-|>eelimiil line « flat, 
trianjrnlar proei^'i, hiiving a frt-e, con<-aVf outer border, and known im <iinibernat'K 
lifTimeni, or ihir liicuimr ligumfttt. From till- latit a Mnall, tiil^on^ linnd. the trian- 
r/nlar Htfiimfiitl, nitw upward and inward behind the lower part of the exlrmal 
abdominal riiij: and il--< iimer pillar, and its fdires mingle with those of its oppo- 
site fellow, .lust above the puiiie biwlv the lemhm presents an ojiening, the 
rj-trrnal abdominal ring (l-'ig. 416t, wlii<h n-sidts from a separation of the 
fibrc«. The aiiertnre sloties upward and oiit«ard. and would be triangular 
well! it not for certain fibre!;, which cross all but the lowest ami widest inch 
of it, ami are called infcrcoliimnar, because they iiro brUrrrn fhr pilfar/i, as the 
inner (np}>er) and outer (lower) rdgf* of the tendon, which marjepn the ei()o> 



THE MUSCLES OF THE ABDOMEIf. 



347 



. 



of the hol«, are called. Th* iniipr jHlIar nins to tlip syniplix'sia and Uio opposite 
ptibic buitp. tho ri);lit pilliir nvi'i'liip|>tii); the- \vii. 'V\w utitcr piDar U utiachttl 
to lli« spino of iW piibio Imhic TIiii>i, liiv rinf; is IkhiiiiIixI below bv tbc 
pubic cre^t, uIkivc bv ibf inner pilliir, (tuU>i(lc by llu- iiitorcHtlumnur fibix-s, nad 
cIstiwlKTf by ilie (Hilcr piilnr. 'I'lio ring i* oociipicd by llw H)M-rniiiliu conl in the 
miiU-, by the rtxitHJ li^tucnt of thv womb in ilie femiilo, and u the fitjH-rfiviiil 
cxlivinity of llie inguinal canal, wlii^ will be dcAcribKl aftttr thin ml of inii»<;I<-» 
(nut Ik^pu «in.sid<-ix-d. From the inltrcoluniiuir fibn-s a ihin layer, llw intntfJummir 
fiiMua, i;* pnilongt'd downwanlovor iheciml sinil testis. .IrfioH, i-onipn-wion nl'ihv 
abdominal vivx^ra, mtalion of ibo pcKis to die Kimo side, flixioii of the pelvis on 
the chest, .Wctr*, the lower ititeixrosial, the ilioingiiiiml, and the ilio-liyp<jgii'<iric. 

Obliqnus IiJt«nins Abdominu (Fig, 414), — " TItc inieniul oblique muAcIo of tl»c 
abdomen. '* SUuution, in the side nml front of the belly-wull, nest deejier tluin 
the exteriuil oblique. Origin, the outer luiif of lite mguiiiul lignment, two-thirds 
of the middle lip of the iliac credit, ami, j^lighlly. (be biiuliKr fnwa, IHrfHion, i 
(fenend, forward, inward, iin<] uiiwanl ; alwi, diixflly upwiinl In-hind, and dow: 
ward in ffwnt. I»«riimn, tin- lower bonhrn* of the eiwlal nirtilagi* froni the 
twelfth to tlw seventh, the cnisifomi pnifex:', thi' linen iilhii, ihe ere^t of the os 
piibi)f, and tin* il io - petit i neat line. The iKirtioii iiiMTlod into Ibe pnbic Ume and 
dii.>-|NvliiH-u1 line enlt-r!* info tlin fnriiintiou of the ennjoimil trtuhm of the iriternal 
obli<(Ue and traiiiivcrNaliH. The lower |M)rrioiii« of the internal ()l)liquc give olF u 
wrie.H of mu-iimlar slijin, wliieb are arranged in Ioo|w in front of and cmbr.ieirig the 
spermatic ts>rd. They con.-tilnle the rttmaiitei- mut^lfi" the snp}>orting niuwele"), 
and the areolar tissue in the B()aoe!* between them is the cranasffric jaxcia. Thi 
crcm.'Wler lifiji iho lt>;*licle. Action, ihi- internal oblique w«npn-**eji the aMominal 
vi^era, depreiuteti the rihii, Hexes the cheat uiMn the pelviit, and rotjtteK it lo tlte 
8ide on which the muscle acta, AVrce*, the ilio-hyjjo- 
ga.Hlrie, ilio-iniriinal, and lower intercoetals. 

Tr&nsversaUs Abdominis iFig. 417), — "The tran^- 
ver^e mu.*i-Ie of tlic id«iii»ien." Si/nonj/m, transveriuri 
alxloniinii). iSHualioit, det-p in the side and front 
ivalls of tlie belly, Orl^iu, tJie inner sorfacea of the 
lower six costal cartilages, the transverse ]iroc«wes of 
tJie lumbar vertehne, the anterior two-thirds of the 
inner lip of the iliac creat, and the outer third of the 
inguinal ligament. lUrrctioit, forward and inward, and 
in lo^fcst part downward. Jnterti'tn, the linen alba 
an<l (by the eonjoiued tendon of tbi^ tnuncle and the 
internal oblique) ibc crest of the os pubis and the 
neighboring jHirt of thv i1io-peetine;il liiK-. The trano- 
vcrMlis «l it." »i'\KT origin interdigitateK wilh ihe 
diaphmgni. Bt-twcen iN eo^inl and tlino r>-[;iiini> iti« 
origin i.- It■mlinou^, and lies bvtweiii (be en'elor Kj>ina; 
and qiiadnihu* lumborum. Thin tendon is otherwise 
known as tlie middle layer of the lumbar fa.'*cia, and 
extends from the last rib to the ilio-Uinibar ligament. 
ApfioH, compreiUiion of the alHlominal visw^ra, Nerff, 
the lower intercostal, iIio-hvjK>;pi.4trie, an*l ilio-In- 
giiinal. The mnsculiir tibres nl the upper tltird of the 
trnnsversalis extend towaixl the middle line so fur B8 
lo lie behind the wetus. 

It K well to note tlmt the three nniwlej^ in the side 
of the abdomen are attached to ribi^ or eo>^tal wirtilngot 
above and li> iliac emst below, resitedively, as follow* : 
the outer nniwhr to the ouler surfstd- and outer lip, the 
inner miiM-le lo the inner 7>nrlhee and inner lip, the mid- 
die muscle to the michlle iinHaoc (the border) and the middle lip. Theohliqnity 







348 



THE ifUSCLEfi. 



of (lit- fibres iif tl)(.-.<i' iiui?ic1cH to t-ni-li iillitT contributes grcally to tlie »trpngtli (if 
tlic iib'loiiiiiial Willi, and U a. »iii:-);M»r(l againr-t horuia. 

'I'lip Jiir/iiinnl Cutml is a cpovit* between the stniflums of the atxlouiiiml wall 
in the repoii of the groin, lhrmij;h which jMSfscs the fiiM.*rniatic conl or the round 
lijptmeiit of the uterus, uefordinjj to the sex of thi- iiiiiuidiial. It i* aii inch mid 
a liiiU" loiiR, exttiHliiip obliquely (lo\vnwur<l und ti>w:ii-d the middle line from an 
aperture, ralb-d llie inlrrnnl iiMtimhuil niitf in tlic tnin.*vt'i>jdi>^ fiiw-iii, a fibroiifi 
layer which liri<'s the ih-i-p :xnrtiic(- uf lh(i tniiiKvcrMiiis miip^cU-. Tlii^ riiij; is on a 
line inidwny Id'twcen the itntcrior iin|>orior iliiir >|)inc luid iIk* pubic fvmjihvgi^, 
nnd iihoiit hair an iin'li aluive the injiiiinitl li^r-inicnl. The cjinnl I'ndx ut the ex- 
t<-rnul alHhiniiiiiil rliij^ in ihir tendon of the cxicniul nbli4|iic niiisi-lc. Its immc- 
diiile boll 111 hirlo.-* are as followx : hrlow, ilu- injriiinal lii,tinu-iit and (iindH'i-uiit's 
lifpmii-nl ; above, the archinfr iwirtion of the internal obliijuc nn<l ii-iniKvcnmli* 
mu.Hcte-i ; behind, the ti-ansversalis faticia, and tlic eonjoinod tendon of the internal 
oblique and tntiisversidis musclcB ; in front, the internal ohiiqne in the «i>|itT |i«ri 
of the canal, the tendon of the external oblique in the lower and greater [wn, 

Qiiadratiis Lumbonun (Fi<t- ;J45), — "The pqiiiiii> ninsele of ihe loins." Sitita- 
tion, in the hind milt of the alMlonicu. Oririhi, the Imck jmrt of the inner !i|> of 
the iliac erc^l, the diodnmbar lipuncnt, and the mmsvi-r-e |micc*.>^es of several 
lower liinibiir verli-linc. IHrrrfloti, iipwnril. J.iyriiimi. llw- lust rib and th<- Iran.— 
verse priH'i-K-B's of sevenil iipwr linnbiir vertehiic. .Ic^j'mi, <le]>lT5wiim of the last 
rib .ind lateni! flexion of the Kjiiin-. .Wrnw, the In.-i thonieic nnd the nppcr 
linnbur. 

THE MUSCLES OF THE THORAX. 



Diftplingmn. 
Intercotibileii ex 1cm i. 



Intcrcostulc^ int<-rni. 
I^evatores coftanim. 



Triaiiftiilarii' (iterni. 
HnlK'nwIalcv 



Diaphragma ll''ig«. 418, 419). — "The diaphnigm," meaning etymological ly 




Flo. us.— Dtaphracm. vta«-«t from III l^nL ITcrtut.l 

**a partition." Sipumifm, the midrilf. The diaphragm in the tiepltim he(wc«n 
the two greal cavitic-s of th« trunk, forming the convex floor of the thorax and 



THE MUHCLKS OF THE THORAX. 



349 



tlic Vitiilb'd r<"wif of ihfi nlKlonicn. Itia Ifiiiliin is cenlrallv located, and I'-, consiv 
(iiipntlv, iu< highosl wire ; and lo this the nniKniilar (wrlion, which i^ )M.-ri(>)icnil, 
rim^s from its oxtonsivp orijrin nt the lower boitiKlarii>^ of ihe thornoic I'ninivwork 
— thir stcrniim, twnic cu^lal cartilages, tvvcrul vtrlcbne, and oerfain fibrous buntk 
h<'i«i><'n tlic**' vertebrw arul the lart rib. 

Kntin Ihc fnutt of the budic-i of iIk- iipiK-r two tiinibnr vcrtoltrn; fmi lb*- right 
Md<- »n<- or two mure) mid tin- n.-lntfil earliiiiffe* riiw Iwo imx-esw*. mlli'd criirH, 
whiL'h unite and an-h ovi-r thi- aorta jiikI iH-lfw the Wt l)u>nieie vertebra, the 
mesial tibn^ onK.-<iii)f to iho (iitjui-iite Mih-. Kmni llie Iiixly of tlit- fimi lumbar 
vertebra ^prin^ a fibrous XxtwA, which imrlMs* over lo the tip of tbe Iransverso 
process, ami from thi^ |)oint to the bijit rib a w-eond l>aml is tttrctclted. The fifBt 




Fin. 419.— Diatilincin. vl#aii(l Iium Iniluw. frratuLI 

\* enlle*) Hf/iimmttim nrrnntum intn-nun ("tile inner nrehed lifpiniein"), anil the 
other, HtfltiniHlitm tircuitlitm fTtmium [" lliv oiiIit iirchc>»! liniment "), liotb give 
origin to miiM-idar tii.*eieiili. Tlio Iiii-jreM i)art of llit- diH|>hr;i^in arises from the 
inner .-iirl'mv of ilie laiil sis eo-itaj ejiriiliigt-s, intenlijjiiaiiiij: "itii tlio IranHVer- 
s^ilis aUlniiihiiH. Finttlty, the i-n.*iforin onire.is givew atiaehnient to a i^mall i«ind. 
The central tendon looks something like a livfoil, h very largv, and to it the 
muscular bundles wtnverge from ihe entire mai^in of the nmseb-. 

The aortic ii|H?ning, already ite-criln"l, gives [Ki»ra^- to the aorta, tliorade duel, 
and larjjc imgos vein. In front of this, higher ii)> ami a little to (lie lefl, in an 
(i|X'ninfr which tninsmii- the le'ophajpis and ]>nenniO)>:n»trie iwrve?. Slill bifjlicr 
and to the riijlit is a thin! liir^c ajx-rliire, devoted to the vena cjivb. Ileyidc lln-se 
great |MTtor!itioti?i arv" a tiiimlx'r of '■tniiil hole!», which trunKmit nerven anil vi-ssels. 

TIk- (liaplira-^m in hifjlier on the rif;lit siflc over ilic liver, and its upper surface 
U somewhat indi-nted at the front eenlml |inrt, ix-ni-nlb tholtmrt. I lt> nerve-supply 
is mainly frxni llic nhrenicx, slightly from tiit- lower inten-oiitalt>. 

When Ihe diiiphragni vontrael", its areb in tialli'nei), and thus the vertical 
i-aiKieily of ilie chi-.i is iiien-Hseil. 

IntercoBtales Exteml | Fiji. 4:20). — " The external belween-the-ribs muscle*," 
the muscles in the oiiler layer lietween the ribs*. Their number rorresprmd"- lo 
that of the intercostal spaces. They ^nerally extend from the tuljcrelcs of the 
ribs to the Jiuiction of itie cartilages ; the remainder of each space is occupied by 




d£0 



THE MVSCLES. 



a fibrous membrane. A simitar membrano Xwvif. tlio muscles from tho anf;les of 
thf ril)H iKickward, Kavh iniisrie urit'CM from llip lower bonier of a rib, rimB 
dowmvurtl w\\<\ forwiirct. iind ii" iii«-rt«l into tlit ii|i}>t'r bonier of the rib n«xt 
below, Tln'ir uetioii liOw llic ribs. Tlicir nerveji arc ihe inUn'ostiil. 

IntercoBt&Ies Internl (l""i(r. -120). — "Tlie itiUTiial betwwii-tbc-nbw miiiwliis." 
Tht'ir luitiilH^r !•■ dial of lint iiiU-ivfNilal Kjitiocv Tbt-y wciijiy tlicsi- iijiuct^n fi-om 
tlio Kti-niiiiii to llii' an^le.i of the ribn, and lievoiiil iIk'hi- points libnai.i nicmbnitu^^ 
fill fill- miiiivti. Eaob muscle arirtcs on the inner nurfiiw of a rib and ilj* rarti1ae<^, 
just above iln lower border, runs down- and backward, aiul i.i inserted iiilo llie 




THHouan •MiiriotAL AAr 



I 



Fid. 4ar,— liiMinxsu] iduhIh In rlibl wall of Uiorai. iTviitui.) 

inner mir&ce of tbc rib just bciioath. Their uclioii ii* uotagrMHl ui>oii. Tlie 
inten'ftstal ner^'ew sii|H)Iv (bem. 

Loviitorc* Cortaruni (Vig. \\\, \.. O.}— " Tbi- Uftors of tbc rilw." Thry are 
twelve in nimibir, Kinb is inserted into tlie outer surface of a rili, between it* 
tubercle untl iiiij^lc, and arise." fiMin tbe ti]) of ibe transverse process of the ver- 
tebra immcdialely above. A few of iliose wliieb aiv lowest m the series have 
• caeli iiii insertion also into a rib beyond tliat proper to itself. The name of the»e 
mnwW indicates ibeir supposed aet ion— elevation of the ribs ; but it U probable 
tliat, insifiiil of this, they oontribiito to the exteiii-ion and Intend flexion of the 
tliomeic iMirl of the vertobnil column. They are supplied by the intercostal 
nerves. 

Triancidjuria St«nii. — " The triangular muscle of tbo nti?rnHm." H^wmym^ 
transversurt thoracis anterior, " tbe front transverse muscle of the oIickI." SUho- 
Hon, on the inner side of the thomcie cajjc in front. Oriifin, the eiiciform ]iro('- 
CBfi, the lower part of the gladiobi!-, and the curtilages of the lower two or th«-e 
true rihs, JJirft^Hon, partly horizontal, partly oblique, partly nearly vertical. 
Jfuu-rlion, tbe outer extremities of the cnstid cartilages from the second to the 
sixth. Action, depression of the ribs, to whose cartilages i( is utlachcd. A'en^ 
the intercostal. 

gnlicostaleB. — "TIui under-the-ribs muscles." Sj/jionym, infnicostalcx, "the 
bcDeath-Uie-ril»s mnscles," Thee an- small, inconstant musele», found usually 
near tho angle* of lb«' rilw, on the inner surface of llicse bones, and extending 
over two intercostal sjwces. Their clin-eli<in is down- and Imclcwanl, and their 
nerves, the int«rco»tal. Their action, whieli niu»t be very insigniiicantj U ««l yet 
determined. 



MUSCLES OF THE FRONT AND SIDE OF THE A'ECK. 



351 



THE MUSCLES OF THE NECK. 

A number of Ihc iinwk* iii tlto Deck (uivc«lr«Mly Ixwti winsi<Ipr«l in conncc- 
tk>n witk lho«r of llie tmi-k. tkc <iirititiiiily "f lifNiii> iir llio elivte functional rela- 
liiin Ix-lwei-n thv fiirnn-r iind tki- Iatt«'r niakiiijr this arran^nK'iit most convt-nJcnt 
in nil (^'•I'S, iim] iiH-vitAl)lt- in otlit^m. 

Then! rvnmin for sindy ihotte mUBRles which are located in the v«iitnil and 
lateral portinnii of the neck. 

MUSCLES OF THE FBONT AND SIDE OF THE MEGK. 



Supcrfirial, 



Pbt^Qia. 



Sienio-hyoideiiB. 
Oin«>-hyoi<le»B, 



I>igaAtrica<i. 
Stvlo-hvoideiiB, 



Sraleniis anterior. 
Scaleoufi miKiius. 



Sterno-ek'ido-tuai^totdeus. 



I^firalij/oid, 



Stern o-t hy rc)i detiB, 
Thy ro-hy oi de UK. 



SujinihifttiiL 



Mylo-liyoideuK. 
Oeni^-liyoideiM. 



Devp Lateral. 



Scalennx pr»iterior. 
K«cUts cupitis intendig. 



PmrrUfirttl. 



RectUH oa[>itis anterior major. liectus cai)iti« anterior minor. 

L<>n^n« colli. 

PI»ty3ma(Fi{j, -121). — "Thttbroiid sheet in»*cle." J^nontym, platyema myoides, 
" the inii.-'ilt>lik<: sheet." Si/iuitiem, in the fnnit iiud iside of the neck, and tin 
lower j>art nf llic side uf the fitot:. f}riffin, the nkin iind arxxihir tii^tii; eoverine ' 
■he iip|ii'r jmrt of the |N>rtiiritIi^ iiiajdr and delliiideti.H, mid llie eliiviciihir ]urt of 
ihe Irapezins, Dim-tion, ii|ivrard «nd inwiinl. Intertion, the outer sorfhoe uf llw 
mandible ai^ far hack an the nui.K.4eter, tlie niut>eiiliir striietni-CH abotit the an^le of 
the moiitli and the lower lip, and tbe corre«|)onding ]»arts of the skin. S<mic 
libre* eross to the opposile side. Arfion, it dniws the auffle of the mouth and the 
lower li[i down- and oiitwai-d. and eontraets the •■kin of the neck, ^ei'rr. the tiicial. 

StAnio-clcida- mastoid ea> (Fig. 42'i). — "The wterntim-clavicie-masloid-prooei^ 
muscle." Sf/noiii/m, stiTno-rna-toidenn, Situation, in the side of the neek. 
Orif/in, the frout of the niauubriiim and inner third of the clavicle. />jVce(tW, 
npwnni and backward. Imicrti