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th;:
LONDON DISSECTOR,
GUIDE TO ANATOMY;
FOR THE USE OF STUDENTS:
coitrsi.s.N'j
BESCR1PT10X OF T3E MCSC L KS, V ESS KI>, X L ItV E>. LT >5 PU ATI I S,
1X1) T1SCERA OF THE UfMlX BOUT, AS THET
IPfElll OX DISSECTION ;
WITH DIRECTION'S FOR THEIR DEMONSTRATION.
FROM THE LAST LONDON tDITION.
RtTISED ASD lOURECTlD BT
EDWARD J. C II A I S T Y, If. D,
LAT6 BE.XO.NSTRATOR OF AKATOSIY IS THE CKlVt8SiTF OF MAKTLASB.
PHILADELPHIA :
ED. HARRINGTON & GEO. D. HASWELL.
1842.
Entered, according to the Act of Congress, in the year eighteen hundred and
thirty-nine, by John Murphy, in the Clerk's Office of the District Court
<©f Maryland-
PREFACE.
In presenting the London Dissector, under its
present form, to the American Student, it may be
proper to remark, that I have been prompted by no
feelings of vanity; no eagerness for authorship. I
felt, even in my own period of study, the difficulty of
procuring brief and satisfactory guides for the student
of anatomy: I perceived with what reluctance he
perused the larger works intended to direct him in
his dissection; how rapidly he hurried over the lengthy
description of the various parts, and I was led to
believe, that a short and sufficiently extensive manual,
would be welcomed as a desideratum by the young
dissector. Believing, that with a few alterations and
additions, the London Dissector might easily be
transformed into a work of this description, I have
been induced to undertake the task.
VH1 PREFACE.
It is but just, however, to acknowledge, that for
these additions I have been indebted to authors of
well known celebrity; that I have drawn freely from
Bell's admirable treatise on Anatomy; and Shaw's
excellent work on Dissection; and that should the
present volume be still received as a work of merit,
the praise must redound to the original author of the
work, not to the compiler. His labor will be amply
compensated, if it but facilitate the progress of the
student, in the acquisition of anatomical knowledge.
CONTENTS
PARTI— THE MUSCULAR SYSTEM.
General Rules for Dissection, 13
Chapter I. — Dissection of the Abdomen, 15
Section I. — Muscles of the Abdomen, 15
See. H. — Description of the Anatomy of the Parts connected with
Hernia, 23
Sec. HI.— Dissection of the Cavity of the Abdomen, ... 39
Chap. D. — Dissection of the Perineum and Organs of Generation
in the Male, 51
Chap. HI. — Dissection of the Organs of Generation in the Female, 59
Chap. IV. — Dissection of the Thigh, 66
Sec. I.— Of the Anterior Part of the Thigh, .... 66
See. H.— Of the Posterior Part of the Thigh, .... 72
Chap. V". — Dissection of the Leg and Foot, IB
Sec. I.— Of the Fore Part of the Leg and Foot, . .... 78
See. H.— Dissection of the Posterior Part of the Leg, S4
Sec. DX— Dissection of the Sole of the Foot, .... 83
Chap. VI.— Dissection of the Upper Part of the Body, 93
Sec. I.— Of the External Parts of the Head, .... 93
Sec. H. — Of the Contents of the Cranium, or of the Brain and its
Membranes, 97
Chap. VH.— Dissection of the Anterior Part of the Neck, 115
Chap. V HI.— Dissection of the Muscles on the outside of the -
Thorax, ....... 122
X CONTENTS.
Page.
Of the Parts within the Thorax, . . . . . .124
Dissection of the Heart, when removed from the Body, . . 123
Chap. IX.— Dissection of the Muscles of the Face, . . .131
Chap. X.— Dissection of the Throat, 139
The Muscles situated about the entry of the Fauces, . . 140
Muscles on the Back Part of the Pharynx, . . . .142
Muscles of the Larynx, 143
Chap. XI.— Dissection of the Orbit of the Eye, . . .146
Muscles situated within the Orbit, 146
Chap. XII.— Dissection of the Muscles on the Posterior Part of the
Trunk and Neck, 149
Chap. XIII. — Dissection of the Muscles situated between the Ribs,
and on the inner Surface of the Sternum, . . . . 162
Chap. XIV. — Dissection of the Muscles situated on the anterior
part of the Neck, close to the Vertebra?, .... 164
Chap. XV. — Dissection of the Superior Extremity, . . .166
Sec. I.— Of the Shoulder and Arm, . . . . . .166
Sec. II. — Dissection of the Fascia and Muscles situated on the
Cubit or Fore Arm, . . . . . . . 171
Sec. III.— Dissection of the Palm of the Hand, . . . ,182
PART II.— THE VASCULAR AND NERVOUS SYSTEMS, 189
Of the Vessels and Nerves situated behind the Peritoneum, . 190
Of the Vessels and Nerves contained within the Pelvis, . . 197
Of the Vessels and Nerves on the Fore Part and Inside of the
Thigh, 200
Of the Vessels and Nerves on the Posterior part of the Thigh, 203
Of the Vessels and Nerves situated on the Fore part of the
Leg and Foot, 207
Vessels and Nerves of the Posterior part of the Leg, . 209
CONTENTS. XI
Of the Vessels of the Brain, 212
Of the Vessels and Nerves seen in the Dissection of the Neck, 213
The course of the Subclavian Artery and its Branches, on each
side, 222
The course of the Brachial Plexus of Nerves, . . . .224
The Dissection of the Axilla, or Arm- Pit, .... 224
Dissection of the Posterior Mediastinum, and of the Nerves and
Vessels which have their course through the Thorax, . 228
Branches of the Intercostal in the Thorax, .... 229
Of the Vessels and Nerves of the Face, 233
Of the Vessels and Nerves met with in the Orbit of the Eye, 238
The Dissection of the Cutaneous Vessels and Nerves of the
Shoulder and Arm . t t 240
Of the Vessels and Nerves of the Superior Extremity, . . 243
The Method of Injecting the Arteries, 252
The Method of Injecting the Heart, 253
The Lymphatic or Absorbent System, 256
Of the course of the Lymphatics, 257
Directions for making Lymphatic Preparations, . . 270
COMPENDIUM
PRACTICAL ANATOMY
GENERAL RULES FOR DISSECTION.
Dexterity in the manual operation of dissection
can be acquired only by practice; the observance,
however, of certain general rules will facilitate the
labor of the student.
1. The position of the hand in dissecting should
be the same as in writing or drawing; and the knife,
held, like the pen or pencil, by the thumb and the
first two fingers, should be moved by means of them
only; the hand resting firmly on the two other fingers
bent inwards, as in writing, and on the wrist The
instrument can thus be guided with much more
steadiness and precision, than when moved by means
of the wrist, elbow, or shoulder.
2. No more of the integuments should at any time be
removed, than is necessary for the present dissection, as
exposure to the air renders the parts dry and indistinct.
3. In dissecting muscular parts, the muscles should
be extended; the cellular membrane which connects
them to the integuments should be placed on the
stretch, and entirely removed with the skin; the
knife should be kept close to the muscles, and carried
steadily in the direction of their fibres, separating a
fasciculus at each stroke: — thus the exposed surface
will appear clean, and the course of the fibres distinct.
2
14 GENERAL RULES FOR DISSECTION.
4. When small vessels are are to be demonstrated,
another method is to be followed; the skin only must
be removed, and the cellular membrane cautiously
dissected from the vessels.
5. During dissection, every little operation should
be practised, which can give the dexterity of hand
so essential to the surgeon: such as the use of the
catheter and probang, the introduction of a probe
through the nose into the Eustachian tube, or nasal
duct, and the cutting down to the various arteries
which may become the object of surgical operations:
as the external iliac, femoral, anterior and posterior
tibial, brachial, radial, and ulnar, &c.
The grand object of the surgical student is to
acquire a knowledge of the relative situation of parts.
This should be kept in view in all his anatomical
labors. Hence, when he is dissecting the muscles,
he should carefully expose the chief blood-vessels
and nerves, and attentively consider their position
with regard to each other, and to the surrounding
parts. The smaller arteries and veins, and the mi-
nute nervous ramifications, will be more advantage-
ously studied on subjects devoted to those purposes,
and prepared by means of injection, immersion in
spirits of wine, &c.
The reader will observe, that, in general, the mus-
cles of one side of the body only are described, because
all the muscles of the body have correspondent ones
on the opposite side, with a few exceptions, which
are pointed out.
The Bursae Mucosae met with in the dissection of
the muscles are not regularly enumerated; but it is
to be understood, that wherever tendons are des-
cribed as rubbing on bones, muscles, or other ten-
dons, a sac is formed by the surrounding cellular
membrane, secreting synovia, to lubricate the parts
in motion.
CHAPTER I.
DISSECTION OF THE ABDOMEN.
SECTION I.
•Muscles of the abdomen, and the parts connected with
them in dissection.
To display these muscles which are ten in number,
five on each side, an incision should be made through
the integuments, from the sternum to the os pubis;
this should be crossed by another passing immedi-
ately below the umbilicus: dissect off the flaps; and
you will expose,
1. The OBLiaucs Descenders Externus. —
This muscle is quite superficial, and covers the whole
of the anterior part of the abdomen. The muscular
part is closely covered by a thin expansion of cel-
lular substance, which should be removed along with
the integuments.
Origin: By eight angular fleshy slips, from the
lower edges and external surfaces of the eight in-
ferior ribs, at a little distance from their cartilages;
the five superior slips unite on the ribs by digitations
with the serratus major anticus; and the three inferior
are connected with the attachments which the latis-
simus dorsi has to the ribs. Often there are only
seven portions. To gain a complete view of this
muscle, the neighboring portions of the pectoralis
major, serratus anticus, and latissimus dorsi should be
dissected with it.
16 LONDON DISSECTOR, OR
The muscular fibres proceed obliquely downwards
and forwards, and about the middle of the side of
the belly terminate abruptly in a thin broad tendon,
which is continued in the same direction over all the
forepart of the belly. Here it covers the anterior
surface of the rectus abdominis; it is very thin at the
upper part, where the rectus lies on the cartilages of
the ribs, and is often removed by the beginner, unless
he is very cautious.
Insertion: Tendinous and fleshy, into two anterior
thirds of the outer edge of the spine of the os ilium;
tendinous, into the whole length of Poupart's liga-
ment, the os pubis, the ensiform cartilage, and the whole
length of the linea alba.
This muscle called also the external oblique, the
descending oblique, or the obliquus. major, aids in
respiration, in flexing the trunk forwards, in raising
the pelvis obliquely when the ribs are fixed; in sup-
porting the abdominal viscera, and in the expulsion of
the urine, the faeces, and the foetus.
In the examination of this muscle, the following
points should be observed:
The Linea Alba, a white line running along the
middle of the abdomen, from the cartilago ensiformis
to the os pubis; formed by the tendinous fibres of the
two obliqui and the transversalis muscles, interlacing
with their fellows on the opposite side.
Linea Semilunaris, a semi-circular white line,
running from the os pubis obliquely upwards over the
side of the abdomen, at the distance of about four
inches from the linea alba; formed by the tendons of the
two oblique and transverse muscles uniting at the edge
of the rectus, before they separate to form its sheath.
Linea Transversa, three or four white lines,
crossing from the linea semilunaris to the linea alba;
formed by the tendinous intersections of the recti
shining through the strong sheath which covers them:
GUIDE TO ANATOMY. 17
These are not evident in all subjects in this stage of
the dissection.
Umbilicus, or Navel. This, which before the in-
teguments were removed, was a depression, appears
now a prominence; it consists of condensed cellular
membrane: — In the foetus, it was a foramen which
gave passage to the two umbilical arteries, the um-
bilical vein, and the urachus.
Amnn.cs Abdominalis, or Ring, an oblique slit
or opening just above the angle of the pubis; formed
by the tendon of the external oblique, divided into
two portions called the pillars or columns of the ring,
one of which (the superior or internal) is attached to
the symphysis, and the other (the inferior or external)
to the angle of the pubis; and allowing a passage to
the spermatic cord in the male, and the ligamentum
teres of the uterus in the female. This slit is very
improperly named a ring, since its' figure is triangular,
the pubis is the base, the two columns are the two
sides of the triangle. The apex has, indeed, a
rounded figure in consequence of some transverse
fibres, which connect the two columns where they
first separate; and it points obliquely upwards and
outwards. It belongs to the external oblique alone,
there being no such opening, either in the internal
oblique, or the transversalis; it is much smaller in the
female than in the male.
Ligamentum Inguinale, seu Poupartii, seu Fal-
lopii, a strong ligament, stretching from the anterior
superior spinous process of the os ilium, to be fixed
to the spine of the os pubis. This in truth is merely
the lower edge of the tendon of the obliquus externus
abdominis, although, in compliance with received no-
tions, I have described it as a separate ligament. It
covers the femoral vessels and nerves, and certain
muscles, and has lately been often described under
the name of the Crural Arch. It is also the same
2*
18 LONDON DISSECTOR, OR
part as the posterior column of the abdominal ring.
The student should not be confused by this multitude
of names; he should remember that the crural arch,
the inferior or outer column of the abdominal ring,
Pouparfs or the inguinal ligament, are so many names
applied to the inferior border of the tendon of the
external oblique.
The student should now dissect the parts in the
groin, and examine the situation of the great inguinal
vessels.
In removing the skin from the groin, he will not
find a strong regular fascia, as on the outer part of
the thigh, but a confused and irregular aponeurosis
coming off from the abdomen, and going down upon
the thigh; strengthened by the intermixture of con-
densed cellular substance, and very loose above the
great vessels.
Immediately under the skin, and above this apo-
neurosis, you perceive a congeries of lymphatic
glands, and sometimes the lymphatic vessels them-
selves can be distinguished by their semi-transparent
coats, and knotted appearance. Also, immediately
under the skin, you will find the Vena Saphena
running from below upwards, at first lying on the
fascia, and then gradually sinking through it to join
the femoral vein, about an inch below Poupart's liga-
ment.
On removing this irregular fascia, we come down
upon the great vessels, which lie deeply imbedded in
cellular substance, and are closely invested and sup-
ported by a firm cellular sheath, or fascia. This
should all be cautiously removed with the scissors,
together with some lymphatic glands imbedded in the
fat. Observe the order in which the parts are situ-
uated under the crural arch: — that the great external
iliac vein lies next to the pubis; — that the external
iliac artery is on the outside of this, in close con-
GUIDE TO ANATOMY. 19
tact with it; — that the anterior crural nerve is half
an inch exterior to the artery, and lies on the iliacus
internus; — and that the outer half of the space left
under the crural arch is filled by the psoas magnus
and iliacus internus muscles. Observe how the cru-
ral arch is stretched over the parts just enumerated;
.how it forms a thin, but firm, sharp, and crescent-
shaped edge towards the pubis (constituting the seat
of stricture in the femoral hernia, and sometimes
called GimbernaCs ligament;) — how the artery is
placed in relation to the angle of the pubis and spine
of the ilium, passing under the middle of the arch.
The dissection of the other abdominal muscles may
now be continued.
Dissect off the serrated origin of the external ob-
lique from the ribs, and from the spine of the os ilium,
and detach it from the obliquus internus, which lies
below it, and which is connected to it by loose cellular
substance, and by small vessels. Continue to separate
the two muscles, till you find their tendons firmly at-
tached, i. e. a little way beyond the linea semilunaris.
Separate the tendon from the crural arch to within
half an inch of the abdominal ring.
2. OBLiauus Ascendens Internus. — It is covered
anteriorly by the obliquus descendens externus, and
posteriorly by the latissimus dorsi. In its action it
assists the obliquus externus; bending the trunk, how-
ever, in the reverse direction, so that this muscle on
one side co-operates with the obliquus externus of the
opposite.
Origin: By short tendinous fibres, which soon
become fleshy, from the whole length of the spine
of the os ilium, and from the fascia lumborum;* also
fleshy from the outer half of Poupart's ligament.
* A tendinous fascia common to this and certain muscles of the back,
as the serratus posticus inferior.
20 LONDON DISSECTOR, OR
The fibres run in a radiated direction; the upper
fibres ascend towards the sternum; the central pass
more transversely across the abdomen; and the infe-
rior descend towards the pubis. The fleshy belly of
this muscle extends beyond that of the external
oblique, before it terminates in a flat tendon.
Inserted into the cartilages of the six or seven
lower ribs, — fleshy into the three inferior, and, by a
tendinous expansion, which is extremely thin, resem-
bling cellular membrane, into the four superior, and
also into the ensiform cartilage. The sheet of tendon
in which the fleshy belly ends, is continued, single
and undivided, into the linea semilunaris; there it
splits into two parts, one passing in front and the
other behind the rectus muscle, and finally unite in
the linea alba; but below the umbilicus the whole
tendon of the internal oblique passes along with that
of the external oblique before the rectus. The in-
ferior edge of the muscle extends in a nearly straight
direction over the spermatic chord to be fixed by a
tendinous attachment to the angle of the pubis.
It is sometimes called the obliquus internus abdo-
minis; — the obliquus ascendens; — or obliquus minor.
About the middle of Poupart's ligament, a delicate
fasciculus of fibres is sent off from this muscle over
the spermatic cord, as it passes under its edge in its
way to the ring. This is named the
Cremaster, and is continued down on the cord,
till it is insensibly lost on the tunica vaginalis testis;
it will be seen in the dissection of the scrotum: Its
use is to suspend, draw up, and compress the testicle.
We must now dissect the attachments of the inter-
nal oblique, continuing our dissection from behind
forwards, and separate it from the transversalis ab-
dominis, which lies beneath it. This separation may
be continued till the tendons of the two muscles
become inseparable. As this muscle lies closely
GUIDE TO ANATOMY. 21
upon the transversa] is, caution is required to avoid
detaching both muscles together.
3. Transversalis Abdominis lies beneath the
last muscle, and reposes upon the peritoneum. —
Arises, tendinous, from the fascia lumborum, and
back part of the spine of the os ilium; fleshy from
all the remaining part of the spine of the ilium, and
from the inner surface of Poupart's ligament; and
fleshy from the inner surface of the cartilages of the
seven lower ribs, where its fibres meet those of the
diaphragm.
The fleshy fibres proceed transversely, and end in
a flat sheet of tendon, which passes with the pos-
terior layer of the internal oblique behind the rectus,
and is inserted into the ensiform cartilage, and into
the whole length of the linea alba; midway, however,
between the umbilicus and os pubis, a slit or fissure
is formed in this tendon, through which the rectus
abdominis passes; and the remainder of the tendon
passes before the rectus, to be inserted into the lower
part of the linea alba, and the os pubis.
Where the transversalis is detached from its ori-
gins, and turned back towards the linea semilunaris,
the peritoneum is laid bare, except in the neighbor-
hood of the crural arch, where it is covered by a
thin fascia arising from Poupart's ligament, and con-
tinued upwards between the peritoneum and transver-
salis muscle, until it is gradually lost. This is named
by Mr. Cooper, its discoverer, the fascia transversalis;
it prevents the bowels from being protruded under the
inferior margins of the obliquus internus and trans-
versalis muscles. It is perforated about the middle
between the ilium and pubes, by an opening for the
passage of the spermatic chord, which then goes
obliquely downwards, inwards, and forwards to the
ring of the external oblique. Thus the abdominal
ring is a canal, having an upper or internal opening,
22 LONDON DISSECTOR, OR
formed in the fascia transversalis, and a lower or
external one in the tendon of the obliquus externiis.
The next muscle to be described is the
4. Rectus Abdominis. — Arises, by a flat tendon,
from the forepart of the os pubis; as it ascends, its
fleshy belly becomes broader and thinner.
Inserted, by a thin fleshy expansion, into the ensi-
form cartilage, and the cartilages of the three inferior
true ribs.
Situation: This pair of muscles is situated on each
side of the linea alba, enclosed in a sheath formed by
the tendons of the oblique and transversalis muscles.
Thus the rectus has in front of it the whole tendon
of the external oblique, and half of the internal; and
behind it, the remaining half of the tendon of
the internal oblique and the entire tendon ot the
transversalis. The muscle is generally divided by
three tendinous intersections; the first at the umbili-
cus, the second where it runs over the cartilage of
the seventh rib, and the third between these; and
there is commonly a half intersection below the um-
bilicus. These intersections constitute the line^e
TRANSVERSA.
At the os pubis, on each side of the linea alba, and
inclosed in the lower part of the sheath of the rectus,
is sometimes found a small muscle, named
5. Pyramidalis. — Origin: Tendinous and fleshy,
of the breadth of an inch from the os pubis, anterior
to the origin of the rectus.
Insertion: By an acute termination, near half-way
between the os pubis and umbilicus, into the linea
alba and inner edge of the rectus muscle.
GUIDE TO ANATOMY. 23
SECTION II.
Anatomy of Hernia.*
It is of considerable importance in this dissection
to have a good body. That of a strong muscular
man is not so well adapted for the display of the
anatomy of the groin, as that of a person who has
died of a lingering disease. The body of a male is
the best for the dissection of the inguinal canal, and
that of a female for the parts connected with femoral
hernia. The subject is to be so placed that the ab-
dominal muscles may be made tense: this is most
conveniently done by placing a block of wood under
the loins. To put the fasciae of the thigh upon the
stretch, one leg ought to hang over the side of the
table. The dissection of the upper part of the exter-
nal oblique is to be made according to the general
rule of removing all the cellular membrane from the
muscular fibre; but this plan must not be followed
lower down than to a line drawn from the one ante-
rior superior spinous process of the ilium to the other;
here, the skin only should be raised; it may be carried
down to three fingers' breadth below the line of
Poupart's ligament.t By this method we shall leave
upon the groin a quantity of condensed cellular mem-
brane, between the layers of which is the arteria
epigastrica superficialis; this membrane may be traced
from that which covers the pectoralis muscle and the
upper part of the muscles of the abdomen; it has
generally received the name of fascia superficialis
communis, because it is of equal importance to the
* Shaw's Manual.
t Tendon of the external oblique; Fallopian or Ponpart's ligament;
crural arch; ligament of the thigh; femoral ligament.
24 LONDON DISSECTOR, OR
inguinal and femoral hernia. This fascia* is now to
be dissected from the tendon of the external oblique.
It has a very slight attachment to the expanded tendon,
and the union between it and the spermatic cord is so
slight, that the handle of the knife can be pushed
between them as far down as to the bottom of the
scrotum. The attachment between the iliacf portion
of Poupart's ligament and this fascia is very strong;
but the connection between the pubic portion of the
ligament and the fascia is so slight, that the handle of
the knife is sufficient to destroy it. We can separate
the fascia with great ease for about an inch below
the edge of this part of the ligament, but we cannot
lift it farther without using the knife; for the fascia
becomes intimately united to the inguinal glands and
to the fascia lata. Although we have raised this
fascia, the accurately defined pillars of the abdominal
ring, which are generally represented in plates as the
first stage of the dissection, will not yet be visible;
but farther dissection will be required, to show them;
for a fascia, which shall be presently described, covers
the ring, so that only a prominence is seen, and which
we shall find to be formed by the spermatic cord.
It is of great importance to make this dissection in
the manner that has been pointed out, because much
of the pathology of femoral hernia may be explained
by it. By looking narrowly into the depression
which has been formed by raising the fascia superfi-
cialis, we may see lymphatic vessels passing across
from the glands to perforate a membrane, which,
* Fascia superficialis of Mr. Cooper; described by Camper and many
others as only a membranous layer; by Scarpa, as a prolongation of the
fascia lata. In the scrotum of the foetus it forms the external lamina of
the peritoneum of Langenbeck.
I The terms iliac and pubic are better than external and internal.
The length of the Poupart ligament may be divided into three portions:
two of the thirds are called iliac, the other pubic, being that which is
nearest to the pubes.
GUIDE TO ANATOMY. 25
though it appears to be a continuation of the lower
edge of Poupart's ligament, has been, by some, de-
scribed as a distinct fascia, under the name of cribri-
form, in consequence of the appearance which it pre-
sents when the lymphatics are cut short. Occasionally
a small gland is projected through the membrane.
The general course of the femoral hernia is either to
displace this gland, or to break through the meshes of
the net-work; and then it will pass into the hollow
which we have just described. The natural course of
the hernia would be, to descend upon the thigh; but
it is prevented from passing farther down, than about
an inch, on account of the close connection which
exists between the fascia superficialis and the glands
of the groin; but when the hernia increases in size,
as it is prevented from descending upon the thigh, it
turns up and breaks through the slight connection
which there is between the pubic part of the liga-
ment and the fascia superficialis, and thus takes the
place of an inguinal hernia. This explains to us that
the acute angle made in the gut is the principal cause
of stricture in femoral hernia; and from the knowledge
of this, we deduce principles upon which we must
proceed to attempt the reduction of femoral hernia,
when so situated. We must endeavour to bring the
base of the sac to a straight line with the neck; and
to succeed in doing this, we must first push the tumor
downwards.
It has occasionally happened that a femoral hernia
has passed up before the surgeon had finished the
operation. We have heard the surgeon blamed for
operating in such a case. It has been said, that the
gut going up before the stricture was cut, proved that
there was no necessity for the operation; but instead
of joining in the censure, we think that it would be
even advisable, in some cases, to cut through the
fascia superficialis, so as to allow the sac to come to
3
26 LONDON DISSECTOR, OR
a straight line, rather than to persevere long in the
use of the taxis. All who have seen many cases of
femoral hernia must allow, that a cut through the skin
and fascia, in an early stage, in many cases, would
not be so dangerous as a protracted attempt to reduce
the gut by the taxis. We have further to consider,
that if it be not possible to reduce a hernia, after
having cut through the fascia superficialis, that it
never would have been reduced by the taxis; in that
case all the steps of the operation must be performed.
We now return to the anatomy of the inguinal
hernia. If we pull the spermatic cord towards the
scrotum, we shall see a thin fascia passing off from
the tendon of the external oblique and attached to the
cord. It has been called fascia propria. It is very
strong in cases of old hernia; but even in the natural
state of the parts, it is so distinct that it obscures the
margins of the ring, (a) By cutting this thin fascia
where it is connected with the cord, and by letting go
the cord, the upper part of the pillars of the ring will
be distinctly shown; but to make the opening of the
ring quite apparent, we must remove the loose fat
with the forceps and scissors from the lower part of
the cord; we shall then have such a view as is given
in plates as the first stage of the dissection. This
opening has been called a ring,* but it might with
more reason be described as a triangle, the base of
which is the os pubis, and the apex the splitting of the
(a) While the fascia superficialis was overlooked; Camper described
a covering to the cremaster muscle, extended from the edges of the
external abdominal ring. This, however, has since been traced in con-
tinuation with the fascia superficialis; is a part of that fascia; and covers
the cremaster as the extended aponeurosis does the other superficial
muscles of the body. 1 would rather retain the name of Camper's fascia,
to this slip of the •superficial fascia; then call it fascia propria; lest it
might be confounded with the fascia propria of a femoral hernia, that is
derived from the cribriform portion of the crural sheath.
* Inguinal ring; ring of the external oblique; or external abdominal
ring. The anatomy of the canal is most accurately described in the
folio edition of Mr. Charles Bell's Dissections, published in 1799.
GUIDE TO ANATOMY. J?
tendinous fibres of the external oblique, and which is
rounded off by a set of cross fibres. The superior
side, or pillar, is simply inserted into the symphysis
pubis; but in the attachment and form of the lower
pillar there is a provision to prevent the compression
of the spermatic cord during the contraction of the
muscles, and it is thus — the inferior pillar is formed
by the pubic extremity of Poupart's ligament, which
is not a rounded tendon that, viewing it on the out-
side, we should expect it to be, but it is so formed,
that part of it passes onwards to be attached to the
linea ileopectinea by a flat broad horizontal tendon,
while its more external part is inserted into the tuber-
cle of the pubes; so that by this form of insertion
there is a groove made for the lodgment of the sper-
matic cord.
The tendon of the external oblique is now to be
cut through in two directions; one in a line drawn
from the superior anterior spinous process of the ilium
to the linea alba, and the other in the linea alba to the
pubes. The tendon of the external oblique is to be
carefully separated from the internal oblique, and is
to be fastened by a hook to the fore part of the thigh.
This will give us a view ol a great part of the ingui-
nal canal. The cord will be seen lying under the
lower margin of the internal oblique, and so connect-
ed by cellular membrane to the edge of the muscle,
that it is difficult for a student in his first dissection
to tell what is muscle and what is cord. This is in a
great measure owing to the cremaster muscle, for it
certainly varies considerably in the manner in which
it takes its origin; the view may be made more dis-
tinct by pulling the cord in a direction towards the
scrotum, and taking off the cellular membrane from
it and from the margin of the internal oblique. By
doing so, we shall see that the internal oblique is not
attached to the whole extent of Poupart's ligament, but
28 LONDON DISSECTOR, OR
that, at two inches and a half from the symphysis pubis,
its attachmeht to the ligament ceases; it then passes
in the form of an arch, to the tubercle,* and to the
linea ileo-pectineaf of the os pubis, so as to assist in
closing the space behind the external ring. At the
termination of the connection of the internal oblique
to Poupart's ligament, the fibres which form the cre-
master muscle come off; but as these fibres occasion-
ally arise from Poupart's ligament, the cord some-
times appears to perforate the internal oblique:^ but
in the greater number of cases, it is sufficiently clear
that the cord passes under the internal oblique, not
through it. In this part of the dissection we may
observe a nerve running through the internal oblique to
pass on the cord, — it is the spermaticus superficialis.
The next stage of the dissection is to show the rela-
tion of the transversalis to the cord. It will be very
difficult to raise the internal oblique from the trans-
versalis, if we commence the separation at the lower
edge of the muscle; but by cutting through those
fibres of the internal oblique, which are connected
with the superior anterior spinous process of the ilium,
we shall find some cellular membrane, and a branch
of the artery called circumflexa ilii, lying upon the
transversalis muscle, which will mark the line in
which we are to dissect, so as to raise the internal
* Spine of the os pubis; tuberculum spinosum; tuberosity of the pubes.
f Linea ileo^pectinea; linea innominata, continuous with the crista.
j M. Cloquet describes the cremaster as formed by some fibres of the
obliquus internus, which are pulled down by the testicle and guberna-
culum, during the descent. He says that these fibres hare two distinct
attachments, one to the belly of the obliquus internus, and the other to
the os pubis; so that each fibre forms a loop (des anses,) similar to
extensible cords, which, when fixed at their two extremities, are
drawn down in the middle. He also says that the testicle occasionally
passes through the substance of the internal oblique, and then, the same
appearance of fibres is found both before and behind the testicle; and
that an inguinal hernia in a female frequently pushes down some of the
fibres of the internal oblique before it, so as to form "un muscle cremas-
ter accidentel."
GUIDE TO ANATOMY. 29
oblique from the transversalis. The internal oblique
is to be separated from the transversalis, and from its
connection with Poupart's ligament, as far as the
origin of the cremaster, and it is then to be turned
over towards the linea alba. The whole of the mar-
gin of the transversalis will now be seen, and we may
observe that its relation to the cord is very nearly the
same as that of the internal oblique; indeed, the
tendons of the two muscles are so closely connected
with each other, that it is almost impossible to sepa-
rate them. It will be also apparent that the united
tendons of these muscles, by their insertion into the
linea ileo-pectinea, form the grand protection against
hernia taking place through the external abdominal
ring; but when this part is weak, in consequence of
the deficiency of the tendons, that hernia which is
called direct, or ventro inguinal, may take place.
The muscular fibres of the transversalis are now to
be very carefully detached from Poupart's ligament,
and then they are to be scraped, not cut, from the
layer of condensed cellular membrane, which is called
the fascia transversalis.*
We have seen the cord pass through the external
oblique, and under the margins of the internal oblique
and transversalis, — and we should now see the inter-
nal ring, described by Mr. Cooper, but this ring must
be made. When we pull the cord towards the groin,
we see part of the cellular membrane which lies under
the transversalis muscle passing down upon it in a
conical form. If we cut this membrane from the
cord, and push it up, and then let the cord go, there
will be a hole, formed in the shape of a ring, but
which, on its iliac side only, has a distinct margin, for
on its pubic side there is only the cellular membrane
* Fascia transversalis, of Mr. Cooper; fascia longitudinals, or r:-flexa.
of M. Cloquet; condensed cellular membrane bjtween the peritoneum
and transversalis muscle, of man v authors.
3*
30 LONDON DISSECTOR, OR
surrounding the epigastric artery and veins. We
may observe also, that the cord at this point has lost
its rounded form— that the vessels are not bound
together, as they are at the external ring, but that the
component parts, separating from each other, give
the cord a flattened form. Having now made an
internal ring,(a) we should attend to the situation of
the epigastric artery. It generally arises from the
pubic side of the external iliac artery, just before it
passes under Poupart's ligament. It will be found to
descend a little, and then to proceed upwards towards
the rectus, passing upon the pubic edge of the sper-
matic cord, and between the fascia transversalis and
the peritoneum; it then enters the substance of the
rectus, about midway between the pubes and umbili-
cus. As this artery is always on the pubic side of
the spermatic cord, it follows, that when the inguinal
hernia passes along the spermatic passage, (which it
does in nine out of ten cases,) the epigastric artery
will be on the pubic side of the hernia; but in the
direct or ventro inguinal hernia, the artery will be on
the iliac side.
Let us now trace the course of a common hernia to
the scrotum, and show what coverings it may have,
and what are the probable causes of stricture.
The muscles and the peritoneum may be cut
through in the usual way of exposing the viscera, and
the flap held out so that the inside of the peritoneum,
and the depression which is found at the part where
the cord passes into the canal, may be seen. In the
greater proportion of cases, it is at this point that
hernia takes place. Having laid down the transver-
salis and internal oblique again in their natural situa-
(a) This openiug is not the creature of the knife, but exists before
dissection has commenced, as perfectly as that on the upper part of the
cone of a funnel, by which the pipe is connected with the body of the
article.
GUIDE TO A>' ATOMY. 31
tions, if we push the finger from within downwards
into the depression of the peritoneum, we shall
exhibit in appearance the first stage of the descent of
a hernia. The finger is as the sac would be, above
the cord, and on the iliac side of the epigastric
artery: by pressing forward the finger, and through
the peritoneum, it will appear under the margins of
the transversalis and internal oblique; and if pushed
farther, it will pass through the external ring. A
hernia lying at this point, would be called inguinal
hernia; but if it were to descend as far as into the
scrotum, it would be called scrotal hernia. This is
the common course of an inguinal hernia, but its rela-
tion to the cord occasionally varies. When we look
to the flattened and dispersed state of the cord at its
upper part, we can understand how it may be split by
the descent of a herniary tumor. In such a case, the
vas deferens is sometimes found on the anterior part,
and the vessels behind; but the vessels are more
frequently on the fore part of the sac.
We may now show what coverings the sac of a
hernia would receive in its passage to the scrotum.
In the common inguinal hernia, the peritoneum
pushes before it, that cellular membrane which has
been called part of the transversalis fascia, and which
we showed must be separated from the cord before
the internal ring can be made; this, when condensed,
forms the innermost covering of the sac. The hernia
then passes under the transversalis and internal
oblique, and as the cremaster muscle runs from the
internal oblique to the cord, it follows, that if the
hernia lies above the cord, the sac must be between
the cremaster and the cord; the fibres of the cremas-
ter which lie above the sac will then be separated, bv
it, from each other, so that the cellular membrane
which connects the scattered fibres, will form that
which is called the cremastic or spermatic fascia.
32 LONDON DISSECTOR, OR
The hernia then passes through the external ring. In
the early part of the dissection, there was a mem-
brane shown passing from the margins of the ring to
the cord, so as to make the ring indistinct; this mem-
brane, which is sometimes called fascia propria, must
also form one of the coverings. The hernia may
now either lie in the groin, or pass into the scrotum,
and in either case it will be covered by the condensed
cellular membrane, called fascia superficialis.
If a patient had worn a truss for some time, all
these fasciae might be distinctly seen in an operation;
but it is of more importance to recollect, that the
peritoneum, which forms the sac, and which, in its
natural state, is very thin, would be found very much
thickened, and particularly at the neck of the sac;
indeed it is occasionally so much thickened, that it
may be separated into a dozen layers. But if it were
necessary to perform an operation for a hernia which
had come down only a few hours before, — after
having cut through the skin and fat, instead of finding
distinct fasciae, such as have been described, only a
little cellular membrane would be seen covering the
sac, and the sac itself would be so thin and transpa-
rent, that the color of the gut may be seen shining
through it.
The anatomy of the fasciae in congenital hernia is
much the same; but the sac which is formed by the
tunica vaginalis, is generally thin at the lower part,
but very strong at the neck.
Before describing what are the probable causes of
stricture, there are some circumstances to be recol-
lected. To produce strangulation, the gut must be
compressed in the whole circle; strangulation cannot
be produced by the muscular fibres which stretch
over the gut, for they relax occasionally; as, for
example, when a patient faints. The hole through
which the gut is pushed is passive; its diameter is
GUIDE TO ANATOMY. 33
never diminished, but the protruded gut swells, and is
increased in size.
The most common seat of stricture in inguinal
hernia is the external ring; for though we do not see
the ring until we have dissected the parts, still we can
feel it, even before the skin is removed, by pushing
the finger up along the cord. If the sac has been
opened, if the external ring has been cut, and the
stricture still continues, what is the cause of stricture?
It cannot be produced by the margins of the internal
oblique or transversalis muscles, for they will relax.
Since we are told by high authority, that the stricture,
in such a case, is caused by the internal ring, we
cannot deny that it may occasionally happen; but we
should be more inclined to say, that the stricture is
not caused by the internal ring itself, but by the neck
of the sac, which is situated at that part. Our reasons
for supposing so, are the following: — In the dissection
of the parts, in their natural or ruptured state, there
is no internal ring, until it is made by pushing up the
cellular membrane which surrounds the cord; and
even then, if we try its strength, we find it very weak,
and particularly on the inner part; while the neck of
the sac is generally so strong, that we might as easily
break a circle of whip cord as tear it. The external
ring, and the neck of the sac, may be considered as
the most common seats of stricture; but there are va-
rieties, into the consideration of which it would be
impossible to enter at present.
There is a species of inguinal hernia called the
direct or ventro inguinal, which has been already men-
tioned as having the epigastric artery on its pubic
side; (a) in several other respects it differs from the
common inguinal hernia. It does not come along the
inguinal canal, but passes directly through the exter-
(a) Certainlj- the iliac side!
34 LONDON DISSECTOR, OR
nal ring; it is not covered by the cremaster or any
part of the fascia transversalis, but only by the fascia
propria and superficialis.(a) The peritoneum is as
liable to be thickened in this species as in the other.
We have seen in operation the sac a quarter of an
inch in thickness. This kind of hernia does not take
place often, but, in proportion to our limited oppor-
tunities, it has occurred to us more frequently than it
appears to have done to Mr. Cooper.
The dissection of the parts connected with femoral
hernia may now be made. We have already de-
scribed the first steps of the dissection. It is abso-
lutely necessary that the limbs be kept forcibly
separated from each other, and that the handle of the
knife only, should be used in removing the glands, as
we are very apt to destroy some of the connections of
the fasciae, if we use a sharp knife while the limbs
are lying straight. When the glands are removed,
we may see the manner in which the fascia lata is
connected to the Poupart ligament; how it dips down
towards the femoral vessels, and how it mounts up
again to cover the pectinalis muscle. The part of
the fascia lata which dips down towards the femoral
vessels, will have a crescentic form; but this will not
be so distinct as is represented in many plates, parti-
cularly in those of Mr. Hey, unless we cut through
the connection which there is between the fascia lata
and the sheath of the vessels; but by doing so, we
would destroy the natural view. This part generally
receives the name of superficial crescentic arch;* for
(a) By this expression, the student would be led to expect that a
scrotal hernia had two coverings from fasciae above the cremaster;
while Camper's fascia is the only one lying between that muscle and
the common integuments.
* Femoral ligament, of Mr. Hey; falciform process of the fascia lata,
of Mr. Allan Burns. All these parts are accurately described in the
folio edition of Mr. Charles Bell's Dissections, published in 1799. He
did not give them names.
GUIDE TO ANATOMY. 35
we shall afterwards see a deep one. It is in this stage
of the dissection that we can understand how some
surgeons have described the femoral hernia as situated
under the fascia lata, while others have described it
as lying above the same fascia; in truth, the femoral
hernia is above one portion of the fascia lata, and
below another, for it is under this part which is called
crescentic arch, and above the portion which covers
the pectineal muscle.
If we pull away the lymphatics which are passing
from the inguinal glands to those of the pelvis, we
shall see a number of holes in a membrane which
connects the lower edge of the Poupart ligament to
the pectineal portion of the fascia lata: this part we
have already noticed. Though it will not appear as
a distinct fascia in our dissection, still it has received
the name of fascia cribriformis from Mr. Cooper, and
as an addition to our stock of names, we have, from
M. Cloquet, septum crurale. It must be very care-
fully examined, for it is the only weak part of the
boundary between the pelvis and the thigh; for, on
the iliac side of this fascia cribriformis, Poupart's
ligament is firmly attached to the fascia lata, and on
its pubic side there is a firm union between the edge
of the third insertion of the Poupart ligament and the
portion of fascia lata which covers the pectinalis
muscle*
We now proceed to the examination of the internal
view. The flap of the abdominal muscles is to be
held up, and the peritoneum is to be carefully torn
from it; by which a useful view will be given, without
our using the knife at all. At about an inch from the
pubes, we see a depression, bounded by the cribriform
fascia, through which the lymphatics pass into the
* While at this stage of the dissection the leg should be moved in
different directions, to show Uie effect of the various positions in relax-
ing or tightening the fasciae.
SQ LONDON DISSECTOR, OR
pelvis from the thigh. The part of Poupart's liga-
ment which is on the iliac side of this cavity, is very
firmly connected with the fascia which covers the
iliacus internus muscle; and on its pubic side, the
united tendons of the internal oblique and transversal is
muscles are inserted into the linea ileo-pectinea. If
we push our finger into this depression, and force it
through the cribriform fascia, it will pass down into
that hollow on the fore part of the thigh, which has
been already described as the situation in which a
femoral hernia lies. The firm connection which
there was between the fascia superficialis and the
glands of the groin, would have prevented us from
passing the finger farther down; but if we turn up the
finger as a hernia does, when it increases in size, we
shall find that it not only presses against the superficial
arch, but that there is also a resistance to it, caused
by a part more deeply situated; this will afterwards
be found to have been produced by that which is
called the deep crescentic arch.
To show this deep arch as a distinct fascia, there
is a great deal of dissection required, and it may very
justly be criticised as one of the tricks of the dis-
sector; but as it is a point of anatomy which is often
talked of, we shall describe what appears to us to be
the easiest mode of displaying it. It may be shown
on the same limb in which the anatomy of inguinal
hernia has been seen, but it would be better to have
another, and then we may proceed thus: — after having
made the dissection of the external oblique, and of the
superficial crescentic arch, in the manner already de-
scribed; we should hold up the flap of the external
oblique, and dissect between it and the internal as
far down as the edge of Poupart's ligament. The
ligament is then to be divided into two laminae, by
forcing the handle of a knife between the point of
union of the external and internal oblique with it; by
GUIDE TO ANATOMY. 37
pushing the knife towards the thigh, it will pass under
the fascia lata; then by moving it in a horizontal direc-
tion between the pubes and ilium, the external oblique
and fascia lata, which are connected together through
the medium of the superficial part of Poupart's liga-
ment, will be so completely separated from the parts
below, that the ligament will appear to be formed by
them only. But if we cut through the attachment of
the ligament to the superior anterior spinous process
of the ilium, and through the fascia lata as far down
as the crescentic arch, (to save the parts below, it is
useful to keep the handle of the knife under the fascia,
as a directory to cut upon,) we shall then have a
view very similar to that we have just destroyed,
for we shall see that the deep crescentic fascia has
nearly the same form as the superficial arch. This
deep arch may be described as being formed on the
iliac side of the vessels, by a connection between the
fascia iliaca and the obliquus internus and transver-
salis, and part of Poupart's ligament; and on the pubic
side, by the fascia transversalis, in union with the
insertions of the tendons of the two muscles into
the linea ileo-pectinea. But this we shall more fully
comprehend by examining the parts from within. On
looking into the pelvis, we see the artery and vein,
surrounded by a proper sheath, lying upon the iliac
fascia, which is the name given to that which covers
the iliacus internus and psoas magnus. If we hold
up the part of the abdominal muscles which has been
left, and look under them towards the thigh, we shall
see an opening like the mouth of a funnel, into which
the vessels, surrounded by their sheath, pass. The
posterior boundary of this space may be described as
formed by a prolongation from the fascia iliaca, and
from which, for a certain space, the vessels can be
easily separated. The anterior boundary may be
traced from the fascia transversalis; being in fact, that
4
38 LONDON DISSECTOR, OR
which is in close connection with the abdominal
muscles, and forms part of that which has been called
the deep crescentic arch. At a short distance below
Poupart's ligament, the fascia iliaca and transversalis
become so closely connected with each other, and
with the cellular membrane which forms the sheath
*of the vessels, that they cannot be traced farther
down upon the thigh.
The space which has just been described as bounded
by the fascia iliaca and fascia transversalis, has re-
ceived various names; by many surgeons it has been
called the crural sheath,* by others, the sheath of the
vessels; and consequently, when the latter describe
femoral hernia, they say that it passes along the sheath
of the vessels; but this language is very incorrect, and
leads to great confusion, for the proper sheath of the
vessels is a distinct part, formed by cellular mem-
brane, which surrounds them through their whole
course from the sacrum to the point where the pro-
funda is given off.
M. Cloquet gives the description of this part too
much in the spirit of a modern discoverer of fasciae
and rings. He says that we have here a part analo-
gous to the inguinal canal; that this (the crural canal)
"has a superior and inferior opening. The inferior
is the opening by which the saphena passes through
the fascia lata to enter the femoral vein." Although
this opening is represented in all the plates of the
anatomy of the groin, given by our own authors, yet
we have not described it, because we think that it is
not of importance, in considering femoral hernia, —
not on account of its situation, but because the con-
nection which there is between the fascia superficialis
and the lymphatic glands, prevents a femoral hernia
* There is no crural ring in the natural state of the parts, but it may
be felt during an operation; and a distinct ring may be shown in a pre-
paration, by removing the whole of the herniary sac. Such an appear-
ance is very well shown in Mr. Cooper's plates.
GUIDE TO ANATOMY. 39
from passing so low down. There are no cases given
by English authors, of hernia protruding through this
hole, but M. Cloquet says, that he and M. Beclard,
have seen many examples of it.
SECTION III.
Dissection of the Cavity of the Abdomen.
The abdomen is divided into three regions, each
of which is again sub-divided.
1 . The Epigastric, or upper region, includes the
part covered at the side by the ribs; its lateral por-
tions are named the right and left Hypochondria,
and its central, the scrobiculus cordis.
2. The Umbilical, or middle region, is the space
immediately under the former, and it extends below
to the anterior superior spines of the ilia. Its sides
are called the lumbar or iliac regions.
3. The Hypogastric, or lowest region, is sub-
divided into three parts, one middle, termed Regio
Pubis, and two lateral, named Inguinal regions.
Before you disturb the viscera, observe the general
situation of those parts which appear on first opening
the abdomen.
1 . The internal surface of the Peritoneum, smooth,
shining, and colorless, covering the parietes of the
abdomen, and the surface of all the visceia.
2. In the triangular portion formed by two ima-
ginary lines drawn from the anterior spinous process
of the ilium to the umbilicus, three ligamentous cords
projecting through the peritoneum, two running late-
rally, and the other in the middle, towards the navel.
These are the remains of the two umbilical arteries
and the urachus.
40 LONDON DISSECTOR, OB
3. The epigastric artery, accompanied by two
veins, may be seen through the peritoneum, ascend-
ing obliquely upwards and inwards from under Pou-
part's ligament.
4. The upper edge of the liver is seen extending
from the right hypochondriac region, across the
epigastric, into the left hypochondriac region: in it
a fissure is seen, into which enters, inclosed in a
duplicature of peritoneum, the ligamentum teres,
which was, in the foetus, the umbilical vein. The
fundus of the gall-bladder, if distended, is sometimes
seen projecting from under the edge of the liver.
5. The Stomach will be found lying in the left
hypochondriac region, and upper part of the epigas-
tric; but, if distended, it protrudes into the umbilical
region.
6. The Great Omentum, or omentum majus, pro-
ceeds from the great curvature of the stomach, and
is spread like an apron over the intestines.
7. The Great Transverse Arch op the Colon
will be seen projecting through the omentum; it
ascends from the os ilium of the right side, crosses the
belly under the edge of the liver, and under the
greater curvature of the stomach, and descending
again upon the left side, sinks under the small intes-
tines, and rests upon the wing of the left os ilium.
8. The Small Intestines lie convoluted in the
lower part of the belly, surrounded by the arch of
the colon.
Such is the general appearance on first opening the
abdomen; this will vary, however, as one intestine
may happen to be more inflated than another, or
according to the position of the body after death.
But to consider the parts more minutely:
1. The Peritoneum. — Observe how it is reflected
from the parietes of the abdomen over all the viscera,
so that they may be said to be situated behind it;
GUIDE TO ANATOMY. 41
trace its reflections from side to side, and from above
downwards; you will see that the external coat of
every viscus, and all the connecting ligaments, are
reflections or continuations of this membrane.
(1.) The four Ligaments of the Liver are form-
ed by the peritoneum, continued from the diaphragm
and parietes of the abdomen.
a, The Middle or Suspensory Ligament, inclos-
ing in its duplicature the Lig amentum Teres.
6, The Coronary Ligament, connecting the
upper surface of the liver to the diaphragm.
c, The Broad Ligament of the right side.
d, The Broad Ligament of the left side.
(2.) The Lesser Omentum, or Epiploon, or the
Mesogastrion, is formed by two laminae of perito-
neum, passing from the under surface of the liver to
the less curvature of the stomach, and containing
in its duplicature the vessels of the liver.
(3.) The Great Epiploon or Omentum. — Ob-
serve, that the peritoneum, coming from both sur-
faces of the stomach, and from the spleen, proceeds
downwards into the abdomen, and is then reflected
back upon itself, till it reaches the transverse arch of
the colon, where its laminae separate to invest that
intestine. This reflection is named the Great Omen-
tum; it is a pouch or bag, composed of four laminae
of peritoneum, and the opening into it is by the Fo-
ramen of Winslow: Observe the situation of this
semilunar opening; it is on the right side of the abdo-
men, at the root of the less lobe, or lobulus spigelii
of the liver; it leads under the little epiploon, under
the posterior surface of the stomach, but above the
pancreas and colon, into the sac of the omentum; —
the omentum sometimes reaches to the lower part of
the hypogastric region, sometimes not beyond the
navel; it contains in its duplicature more or less of
adipose substance.
4*
42 LONDON DISSECTOR, OR
(4.) The Mesentery. — Observe, that the perito-
neum, reflected from each side of the vertebrae, pro-
ceeds forward, to connect the intestines loosely to the
spine; that it begins opposite to the first lumbar ver-
tebra, crosses obliquely from left to right, and ends
half-way between the last lumbar vertebra and the
groin. At its commencement, it binds down the
extremity of the duodenum, and terminates where the
head of the colon begins. The great circumference
which is in contact with the intestines, is very much
plaited or folded, and is several yards in length.
Between the laminae of mesentery, observe the Con-
globate Glands, less numerous in old age: the
branches of the superior mesenteric artery ramifying
and forming arches; the mesenteric veins accompa-
nying the arteries; the trunk of the lacteals, situated
contiguous to the mesenteric artery on its left side.
It may sometimes be inflated by the blow-pipe.
Nerves also run in the mesentery, but are not easily
demonstrated.
(5.) The Mesocolon is similar to the mesentery,
and connects, in like manner, the colon to the spine.
2. Hepar, the Liver. — Situation: Partly in the
right hypochondrium, which it fills up, reaching as
low as the kidney of that side, partly in the epigas-
trium, and running also some way into the left hypo-
chondrium.
Connected by its four ligaments to the inferior sur-
face of the diaphragm, and by the smaller epiploon to
the small curvature of the stomach: — The little
epiploon should now be removed, to discover the
different parts of the liver.
Observe its superior or convex surface adapted to
the arch of the diaphragm; the inferior or concave
surface resting on the stomach; — the posterior or
thick edge lying against the vertebrae, and the anterior
thin margin corresponding to the lower edge of the
GUIDE TO ANATOMY. 43
chest; — Observe the three lobes of the liver; — the
great or right lobe; — the small or left lobe; — the lobu-
lus spigelii; — the great fissure, separating the right
and left lobe, and receiving the suspensory ligament,
and the ligamentum teres; — the cavity of the portae
between the great lobe and lobulus spigelii; — the fis-
sure on the right side of the lobulus for the vena cava
inferior, which fissure is almost a complete foramen;
the notch in the back-part for the vertebras; — the
depression in the right lobe for the gall-bladder.
Observe the vessels in the cavity of the portae, the
hepatic artery on the left side, the ductus communis
choledochus on the right side, and betwixt, but at the
same time behind them, the vena portae; they are all
surrounded by a plexus of nerves. These vessels
and nerves pass along the edge of the mesogaster, or
little omentum, surrounded and connected by adipose
and cellular substance; the part is called Capsula
Glissoni. Observe that the ligamentum teres was
the umbilical vein of the foetus, entering the vena
portae, and that the ductus venosus in the foetus (ob-
literated in the adult,) leaving the vena portae, passed
into one of the venae cavae hepaticae.
3. Vesicula Fellis, the Gall-Bladder. — Situa-
tion: In the right hypochondrium, in a superficial
depression on the under surface of the right lobe of the
liver; it sends off the Ductus Cysticus, which, unit-
ing with the Ductus Hepaticus, forms the Ductus
Communis Choledochus; this perforates the first
curvature of the duodenum.
4. Ventriculus, the Stomach. — Situation: In the
left hypochondriac and epigastric regions: Connected
to part of the inferior surface of the diaphragm, to
the concave surface of the liver by the little epiploon,
to the spleen by a reflection of peritoneum, and to
the arch of the colon by the great omentum. Ob-
serve its greater curvature looking downwards, its
44 LONDON DISSECTOR, OR
less curvature looking upwards; and its two lateral
surfaces. Observe the bulging extremity on the left
side, the cardia or upper orifice, where the oesopha-
gus enters, and the pylorus, or lower orifice, at the
end of the small extremity.
5. The Intestines. — They are divided into two
classes, the small and the large.
The small intestines are again subdivided into the
duodenum, jejunum, and ileon; the large into caecum,
colon and rectum.
(1.) Small Imtestines. — They are about four
times as large as the body.
«, The Duodenum is broader than any other part
of the small intestines, but is exceedingly short: leav-
ing the pylorus it passes upwards, under the liver and
gall-bladder; "and turning upon itself, it descends, as
low as the right kidney; in which space it receives
the pancreatic and cystic ducts; it then crosses before
the renal vessels and the aorta, and being firmly
bound down by the peritoneum, upon the last vertebra
of the back, it ascends from right to left, till it is lost
under the root of the mesocolon.
By turning back the colon and omentum, over the
brim of the thorax, and pushing down the small intes-
tines towards the pelvis, you find the duodenum com-
ing out from under the mesocolon, but still tied close
to the spine; it terminates in the jejunum, exactly
where the mesentery begins.
6, The Jejunum constitutes the first or upper half
of the remaining small intestines, and is situated more
in the upper part of the abdomen; it is redder, and
its coats feel thicker to the touch, from the greater
number of the valvulae conniventes on its inner sur-
face; and its diameter exceeds that of the ileon.
c, The lower half is named Ileon; it is situated
more in the lower part of the abdomen, and termi-
GUIDE TO ANATOMY. 45
nates in the great intestine, by entering the caput coli,
or beginning of the colon.
The course of the canal, independently of its con-
volutions, is from the left lumbar region, where the
duodenum emerges from under the mesocolon to the
right inguinal region, where the ileon terminates in
the caput coli.
(2.) The divisions of the great intestines.
d, The Cecum, or blind gut, is tied down by the
peritoneum to the loins on the right side, lying in the
space under the right kidney, and hid by the convo-
lutions of the ileon. On its posterior part there is a
little appendage, of the shape of an earth-worm,
named Appendix Cceci Vermijormis.
e, The Colon. — Its commencement at the caecum
is termed Caput Coli, or head of the colon; it passes
from the caecum over the right kidney, to which it is
connected by cellular substance, and having passed
under the gall-bladder, which, after death, tinges it
with bile, it goes across the upper part of the belly,
forms the Great Transverse Arch. In its whole
course it is contracted into cells by its muscular
fibres, which are united together, forming longitudinal
bands-, and to its surface are attached some fatty pro-
jections named Appendices Epiploicae. These two
circumstances may distinguish the large from the
small intestines; more than their difference of size.
For when the large intestine is empty, it contracts,
and may be even smaller than the small; but if it were
inflated, it could be distended to a much greater
degree. The colon then passes backwards under
the stomach and spleen into the left hypochondrium;
and descending over the left kidney, it is again tied
down; finally it turns over the brim of the pelvis,
being at this part unconfined, and forming a loose and
remarkable curvature, which is named the Sigmoid
or Iliac Flexure, terminates in
46 LONDON DISSECTOR, OR
The Rectum. — Which descends along the anterior
surface of the sacrum and os coccygis to the anus.
By drawing the stomach towards the right side,
you will expose,
6. The Lien, or Spleen. — Situation: In the left
hypochondriac region, between the great extremity
of the stomach, and the neighbouring false ribs, under
the edge of the diaphragm, and above the left kid-
ney; to all of which it is connected by the perito-
neum. It is of an oval figure; slightly convex on its
external and irregularly concave on its internal sur-
face, and divided by a longitudinal fissure, into which
its vessels enter.
7. The Pancreas. — This gland was in part seen
on removing the little epiploon; it is more fully
exposed,tby tearing through the great epiploon between
the great curvature of the stomach, and the transverse
arch of the colon. It lies in the cavity into which
the foramen of Winslow leads; it extends from the
fissure of the spleen across the spine, under the pos-
terior surface of the stomach, and terminates within
the circle formed by the duodenum; it is only covered
on its anterior surface by the peritoneum.
The Pancreatic Duct pierces the coats of the
duodenum, and enters the cavity of that intestine, by
an orifice common to it, and to the ductus communis
choledochus. The duct runs along the very centre
of the gland, where the whiteness of its coats will
readily enable the student to distinguish it.
All the abdominal viscera may now be removed,
except the rectum, where it descends into the pelvis,
which, being tied, should be allowed to remain, for it
belongs to the demonstration of those parts: or the
liver and its vessels, with the pancreas, may be left;
and the vessels entering the portae of the liver traced.
The peritoneum should now be carefully dissected
from the diaphragm, and from the sides and back-part
GUIDE TO ANATOMY. 47
of the abdomen, that the parts which lie more imme-
diately behind that membrane may be examined.
8. Renes, the Kidneys. Two glandular bodies,
situated in the posterior part of the abdominal cavity,
one on each side of the lumbar vertebras, between the
last false rib and the spine of the ilium, and imbed-
ded in a quantity of adipose membrane.
Each kidney has a concavity turned obliquely for-
wards and inwards; and is convex obliquely back-
wards and outwards; its superior extremity is nearer to
that of the opposite kidney than the inferior. Observe
the renal or emulgent artery entering the concave sur-
face, and the vein and ureter passing out. Notice the
course of the ureter, it passes behind the peritoneum
over the psoas muscle into the pelvis, and running
between the rectum and bladder, penetrates the latter.
9. The Capsulje Renales. — Are two glandular
bodies situated on the upper extremity of each kid-
ney, their figure is irregular, crescent-like, or some-
what triangular.
By the removal of the peritoneum, several muscles
are exposed, situated at the superior and posterior
parts of the abdomen.
DlAPHRAGMA, the DlAPHRAGM, Or MlDRIFF.
This is a broad, thin, muscular septum between the
thorax and abdomen; it is concave below, and convex
above, the middle of it on each side reaching as high
within the thorax as the fourth rib. It is divided into
two portions:
1. The superior or greater muscle of the dia-
phragm, forms the transverse partition between the
chest and abdomen,
Arising, by distinct fleshy fibres, 1 . From the pos-
terior surface of the ensiform cartilage; 2. From the
cartilages of the seventh, and all the false ribs; 3.
From the ligamentum arcuatum, which is a ligament
extending from the top of the twelfth rib to the lum-
48 LONDON DISSECTOR, OR
bar vertebrae, forming an arch over the psoas and
quadratus lumborum muscles. The fibres run, in dif-
ferent directions, like radii from the circumference to
the centre of a circle, and are
Inserted into a broad tendon (tendinous centre, or
cordiform tendon,) which is situated in the middle of
the diaphragm, and in which, therefore, the fibres
from the opposite sides are interlaced.
2. The inferior or less muscle, or appendix of the
diaphragm, lies on the bodies of the vertebras, and
Jlrises, by four small tendinous feet, on each side,
from the second, third, and fourth lumbar vertebras;
these tendons soon join, to form a strong pillar on
each side, named the Crus of the Diaphragm. The
crura run obliquely upwards and forwards, form too
fleshy bellies, a fasciculus of each of which crossing
over to the other, decussates with the opposite one,
and thus forms the interval of the two crura into a
superior and inferior opening.
Inserted into the posterior part of the middle cor-
diform tendon.
Situation: The diaphragm is perforated in its fleshy
and tendinous parts by several blood-vessels, and
other important organs.
(1.) The aorta lying close upon the spine passes
between the tendinous part of the crura; and the tho-
racic duct passes betwixt the orta and the right crus.
(2.) A little above, and to the left side of the aorta,
the oesophagus, with the eighth pair of nerves attached
to it, passes through an oval fissure formed in the
fleshy columns of the inferior muscle. These two
parts are separated by the decussating fasciculi just
described.
(3.) The vena cava perforates the tendon towards
the right side by a triangular hole.
(4.) The posterior intercostal nerve, and branches
of the vena azygos, perforate some of the posterior
GUIDE TO ANATOMY. 49
fibres of the crura: — The splanchnic, or anterior
intercostal nerve, also passes through an opening in
the substance of the crura.
(5.) On each side of the sternum there is a small
fissure, where the peritoneum and pleura are only-
separated by adipose membrane.
Use: The diaphragm is one of the chief agents in
respiration; it also acts in coughing, laughing, and
speaking, and in the expulsion of the urine and faeces.
The muscles situated within the posterior part of
the abdominal cavity are four on each side.
1. The Psoas Parvus. — It arises, fleshy, from the
sides of the last dorsal, and first lumbar vertebra; it
sends off a small long tendon, which, running on the
inside of the psoas magnus, is
Inserted, thin and flat, into the brim of the pelvis,
at the junction of the os ilium and pubis.
This muscle lies on the anterior part of the loins,
betwixt the psoas magnus and the vertebras; some-
times, however, it is wanting.
2. The Psoas Magnus. — It is situated between the
psoas parvus and iliacus internus. It arises, fleshy,
from the side of the body, and transverse process of
the last vertebra of the back, and in the same manner
from all those of the loins, by as many distinct slips.
It runs down over the brim of the pelvis, and is
Inserted, tendinous, into the trochanter minor of the
os femoris, and fleshy, into that bone immediately
below the trochanter.
3. The Iliacus Internus. — This muscle fills up
the internal concave surface of the os ilium. It arises
fleshy, from the transverse process of the last lumbar
vertebra, from all the inner margin of the spine of the
os ileum, from the edge of that bone between its
anterior superior spinous process and the acetabulum
and from all its hollow part between the spine and the
linea innominata. Its fibres descend under the outer
5
50 LONDON DISSECTOR, &C.
half of Poupart's ligament, and join the tendon of the
psoas magnus.
Inserted with the psoas magnus into the trochanter
minor. This muscle is covered by a pretty strong
fascia, which is inserted into the crista of the ilium,
and into the crural arch: the Fascia Iliaca. The
latter insertion prevents the bowels from descending
under Poupart's ligament, except at the inner edge of
the iliac vein, which is accordingly the situation of
the crural hernia, and which the student should exam-
ine most carefully. A part of this fascia is also
continued behind the femoral vessels over the pubis,
to form a part of the sheath which incloses those
vessels.
4. The Quadratus Lumborum. — This muscle
arises, tendinous and fleshy, from rather more than the
posterior third of the spine of the os ilium.
Inserted into the transverse processes of all the ver-
tebras of the loins, the posterior half of the last rib,
and, by a small tendon, into the side of the last ver-
tebra of the back.
It is situated laterally at the lower part of the spine,
more outwardly than the psoas magnus, between the
origin of the psoas and the transversalis abdominis.
CHAPTER II.
DISSECTION OF THE PERINEUM AND OF
THE MALE ORGANS OF GENERATION.
The muscles to be demonstrated being imbedded
in loose cellular substance, are to be dissected with
great caution. The Rectum having been cleansed,
hair may be introduced into its extremity,, to keep the
anus gently protruding during the dissection; or a
cork, with a loop attached to it, may be introduced,
and the mouth of the gut tied upon it; — this last method
is preferable, as the intestine can then be turned in
every direction. To facilitate the dissection introduce
a staff into the bladder, to mark out the situation of
the urethra; and place the subject in the same position
as for the lateral operation of lithotomy.
The muscles of the perineum consist of five pair,
and a single muscle:
Erector Pe>is,
Accelerator Urix^:,
TRA>"SVERSUS PeRI>\EI,
Levator Aki,
Coccygeus.
In commencing this important dissection, recollect
that the erector muscle, covering the cms of the
penis, arises from the tuber ischii, and ascends on the
inside of the ramus of that bone, — that the transversus
perinei arises from nearly the same point, and crosses
the perineum, lying often at a considerable depth in
the adipose substance. The tuber ischii then be-
comes a proper place for the commencement of the
on f Sphincter
► each ^ Ani, single
side. £ muscle.
52 LONDON DISSECTOR, OR
dissection; carefully tracing the muscles arising from
that point, remove all the cellular substance, situated
in the perineum, while the muscular fibres are left
untouched; the Raphe or line running along the skin
of the perineum, marks the place where the opposite
muscles meet. The appearance of these muscles
will vary in different subjects. In the weak and
emaciated, the fibres will be pale, and not very evi-
dent, while in strong muscular men, who have expired
suddenly, they will be very distinct. This dissection
is to be continued till all the parts between the tube-
rosities of the ischia on each side, and between the
pubis before, and the tip of the os coccygis behind,
are fairly brought into view. Observe
The Erector Penis covering the crus of the
penis.
The Accelerator Urinze embracing the bulb
and lower part of the Corpus Spongiosum of the
urethra.
The Sphincter Ani, encircling the anus.
The Transversus Perin^ei, crossing the perineum
transversely.
1. The Erector Penis — Arises, tendinous and
fleshy, from the tuberosity of the os ischium; its
fleshy fibres proceed upwards over the cius of the
penis, adhering to the outer and inner edges of the
ascending ramus of the os ischium, and of the de-
scending ramus of the os pubis; — but before the two
crura meet to form the body of the penis, it ends in
a flat tendon, which is lost in the strong tendinous
membrane that covers the corpus cavernosum.
2. The accelerator Urinje — JJrises, by a thin
tendinous expansion, from the descending ramus of
the pubis, and from the ascending ramus of the
ischium, nearly as far down as the tuber; the
fleshy fibres are seen coming out from the angle
between the crus and the corpus spongiosum urethrae;
GUIDE TO ANATOMY. 53
they proceed obliquely downwards and backwards,
embrace the bulb and lower part of the corpus spon-
giosum, and are
Inserted into a white tendinous line in the middle of
the bulb of the urethra, joining there with the muscle
of the opposite side. The lowermost fibres run nearly
transversely, while the superior fibres are very oblique.
This muscle, called also, ejaculator seminis, forces
the urine and semen forwards, by compressing the
lower part of the urethra, and propels the blood
towards the corpus spongiosum and the glans penis.
3. The Transversus Perin.ei— Arises from the
tough fatty membrane that covers the tuber ischii,
immediately behind the attachment of the erector
penis; thence its fibres run transversely inwards.
Inserted into the central point of union where the
sphincter ani touches the accelerator urinae, and
where a kind of tendinous projection is formed, com-
mon to the five muscles.
Use: This muscle, or the transversalis penis serves
to dilate the bulb of the urethra, to prevent the anus
from being too much protruded, and to retract it
when protruded.
There is sometimes another slip of fibres, the
Transversus Perinjei Alter, which has the same
course, and is inserted into the posterior part of the
bulb of the urethra.
4. The Sphincter Ani is a broad circular band
of fibres which surround the extremity of the rectum,
passing nearly as far out as the tuber ischii; the fibres
of each side decussate where they meet.
It arises from the extremity of the os coccygis be-
hind;* and is inserted before into a tendinous point
♦The sphincter ani often arises by an elastic tendon, approaching to
the nature of a ligament, from the apex of the os coccygis. This tendon
is of some length; it gives off muscular fibres, which surround the
extremity of the rectum.
5*
54 LONDON DISSECTOR, OR
common to this muscle, and to the accelerators urinae
and transversi perinei. This tendinous point is worthy
of remark; it seems to consist in part of an elastic
ligamentous substance. .
It closes the anus, or extremity of the rectum, and
draws down the bulb of the urethra. It is in a state
of constant contraction, independently of the will, in
order to prevent the contents of the rectum from
escaping except at those times when we make an
effort to evacuate them.
More deeply seated than the muscles now describ-
ed, we see some of the fibres of
The Levator Ani. — This muscle, called also
Musculus ani Latus, arises from the inside of the os
pubis, at the upper edge of the foramen thyroideum,
from the inside of the os ischium, from the tendinous
membrane covering the obturator internus and coccy-
geus muscles; — from this semicircular origin its fibres
run down like radii towards a centre, and are
Inserted into the two last bones of the os coccygis,
and the verge of the anus, passing within the fibres of
the sphincter ani, but on the outside of the longitudinal
fibres of the gut itself.
This muscle, with its fellow, very much resembles
a funnel, surrounding the extremity of the rectum, the
neck of the bladder, (which passes through a slit in its
fibres,) the prostrate gland, and part of the vesiculae
seminales.
It serves to draw the rectum upwards after the
evacuation of the faeces, to assist in closing it, and to
compress the vesciculas seminales, and other viscera
of the pelvis.
6. The Coccygeus arises, tendinous and fleshy,
from the spinous process of the os ischium, and covers
the inside of the posterior sacro-sciatic ligament; it
forms a thin fleshy belly.
GLIDE TO ANATOMY.
55
Inserted into the extremity of the os sacrum, and
the lateral surface of the coccygis, immediately before
the gluteus maximus, and between it and the levator
ani.
It supports and moves the os coccygis forwards,
and connects it more firmly with the sacrum.
The acceleratores urinae and transversi perinei must
now be removed from their insertions. They may be
left suspended by their attachments to the bone. The
rectum must be separated from the bladder, and pulled
downwards. This dissection will expose a great
part of the levator ani; — the neck and body of the
bladder; — the prostrate gland; — the vesiculae semina-
les; — the glandulae anteprostatae; — part of the vasa
deferentia; part of the ureters; — the urethra, its mem-
branous part, its bulb, and corpus spongiosum; — the
crura penis, and their origins from the ischium; —
Observe,
1 . The connection of the bladder and rectum, and
the cellular substance interposed between them,
2. The prostate gland: Situated between the blad-
der and rectum, surrounding the beginning of the
urethra in such a manner, that one third of its thick-
ness is situated above the urethra, and two-thirds
below it; its shape is somewhat pyriform, and its
consistence between cartilage and ligament.
3. The Urethra. — The curve should be carefully
observed. The urethra begins at the neck of the
bladder; it is a continuation of that part of the bladder
which in the erect posture is lowest. (1.) Its begin-
ning is imbedded in the prostate gland. (2.) Its
membranous part is very short, — situated between
the prostate gland and bulb of the urethra: — in dis-
secting, remark, that there is a firm fasciculus of
fibres surrounding it, and connecting it and the pros-
tate gland to the arch of the pubis; this fasciculus
gives support to the urethra, and is termed the liga-
56 LONDON DISSECTOR, OR
mentum triangulare urethrae. It is sometimes described
as a compressor muscle of the prostate gland. (3.)
The urethra then enters the corpus spongiosum.
4. The Corpus Spongiosum Urethra consists
of a plexus of minute veins covered externally by a
thin but uniform tendinous sheath; it surrounds the
urethra from a short distance from the bladder to its
extremity: at its beginning, it forms a considerable
body of a pyriform shape, termed the Bulb of the
Urethra; that part of the bulb which is below the
urethra, is named the pendulus part of the bulb. The
corpus spongiosum is expanded at its anterior extre-
mity, to form the glans penis.
5. The Glandule Anteprostat^:, or Cowper's
Glands, are two small glands of the size of peas, situ-
ated immediately before the prostate, and between
the membranous part and bulb of the urethra.
6. The Vesiculjs Seminales are two soft, whitish,
knotted bodies, about three or four fingers-breadth in
length, and one in breadth, and about three times as
broad as thick: Situated between the rectum and lower
part of the bladder obliquely, so that their inferior
extremities are contiguous, and are affixed to the base
of the prostate gland, while their superior extremities
are at a distance from each other extending outwards
and upwards, and terminating just on the inside of the
insertion of the ureters in the bladder.
7. The two Vasa Deferentia are seen running
betwixt the vesiculaa seminales, and united to them and
to the base of the prostate. Observe that part of the
bladder, left between these tubes, and connected by
cellular substance to the rectum, which is pierced
when the bladder is punctured from the latter part.
8. The Corpora Cavernosa Penis arise, on
each side, by a process named the Crus, from the
ramus and tuber ischii, ascend along the ischium and
pubis, and are united immediately before the cartila-
GUIDE TO ANATOMY. 57
ginous arch of the pubis; — they are covered by a strong,
white, shining, fibrous, ligamento-tendinous substance,
which is very elastic. Internally they are cavernous,
and are separated from each other by a septum, which,
from being perforated, is named Septum pectirriformt.
By the union of the corpora cavernosa, two grooves
are formed: — (1.) A smaller one above, in which two
arteries pass, a large vein or two betwixt them, and
some large twigs of nerves. (2.) A larger groove
below, which receives the urethra.
9. The Vesica Urinaria, or Urinary Bladder,
is situated within the pelvis, immediately behind the
ossa pubis, and before the rectum. It is covered on
its upper and back part by a reflection of peritoneum:
in front and below (where it is contiguous to the rec-
tum,) it is connected by cellular membrane to the sur-
rounding parts. Shape, oval, but flattened before and
behind, and, while in the pelvis, somewhat triangular.
Divided into the fundus or bottom, corpus or body,
and cervix or neck. In the contracted state, the fundus
is the broadest and roundest part, but, when distended,
the cervix is broader than any other part. At the top
of the bladder, above the symphysis pubis, may be
observed, the superior ligament of the bladder, con-
sisting of the Urachus, a ligamentous cord, which runs
up between the peritoneum and linea alba, as far as the
navel,* and two of the ligamentous cords, which are
the remains of the umbilical arteries, and run up from
the sides of the bladder. The ligamentum inferius
vesicas connects the bladder to the upper and inner
side of the ossa pubis.
Observe the parts of the bladder not covered by
peritoneum; as they are the situations of surgical
operations. These are the whole anterior surface,
lying against the pubis, and rising above it, when the
* In the foetus, it is a prolongation or production of the coats of the
bladder.
58 LONDON DISSECTOR, OR
bladder is distended, so that it may be punctured
above the pubis; — the sides, at the very lowest part of
which the incision is made in the lateral operation of
lithotomy, and where the viscus may be punctured
from the perineum; — and the inferior surface, resting
on the rectum, and allowing us to puncture from it.
Observe also the direction of the axis of the bladder,
in conformity with which all instruments should be
introduced.
10. The entrance of the ureters into the bladder on
the outside of the vesiculae seminales.
11. The rectum, following the curve of the os
sacrum, and os coccygis.
12. The prepuce is a fold of skin forming a sheath
or covering for the glans penis. It makes a duplica-
ture extending along the flat part of the glans from its
basis to the orifice of the urethra, termed Frjenum
Pr^putii.
To have a more connected view of the relative
situation of these important parts, one side of the
pelvis should now be removed, by dividing the sym-
physis pubis, and by sawing through the os ileum, or
separating it at its junction with the sacrum. By
carefully removing all the cellular membrane, the
student will be enabled more accurately to examine
the situation of the parts above described.
OF THE SCROTUM.
The scrotum consists externally of a loose, rugose
skin, and internally of condensed cellular membrane,
which has been described as a muscle, under the
name of Dartos.
On dividing the anterior part of the scrotum, on
either side of the raphe, we expose,
1. The Testicle, a gland of an oval flattened form,
GUIDE TO ANATOMY. 59
covered by the tunica vaginalis, having on its upper
edge an appendage termed Epididymis.
2. The Spermatic Chord, connecting the testicle
to the abdominal ring. It consists of,
a, The spermatic artery, a branch of the aorta;
this divides into several branches, which enter the
upper edge of the testicle.
6, The spermatic veins, which form a plexus, that
terminates in the abdomen, in a single vein.
c, The spermatic nerves, which come from the
intercostal and lumbar nerves.
d, The vas deferens, or excretory duct of the tes-
ticle; — this is situated in the back part of the chord,
and is distinguished by its firm cartilaginous feel.
e, The spermatic absorbents.
/, These parts are all connected by cellular mem-
brane, and by the tunica vaginalis, which is covered
by a thin muscle.
g, The cremaster, — this arises from the obliquus
descendens internus, and is lost on the tunica vaginalis.
The internal proper covering of the testicle is a
serous coat, and is denominated the tunica albuginea.
CHAPTER III.
DISSECTION OF THE ORGANS OF GE-
NERATION IN THE FEMALE.
Previous to the dissection, it will be proper to
examine the external parts.
The Mom Veneris is a rounded prominence,
covered with hairs after puberty, situated at the
lower part of the belly, and arising on each side
gradually from the groins; it consists of the common
60 LONDON DISSECTOR, OR
integuments, with an additional quantity of cellular
and adipose substance, and lies upon the fore part of
the ossa pubis. From the inferior part of the mons
veneris arise
The Labia Externa, called also the labia or alae
pudendi: — they are continued downwards and forwards
in the direction of the symphysis pubis, and terminate
in the perineum anterius: they consist of integuments,
cellular substance, and fat, — are thicker above than
below, — and are red and vascular on their inner side.
The places where the labia are joined to each other
above and below, are termed Commissures.
The longitudinal cavity or fissure, situated betwixt
the labia, and extending from the mons veneris to the
perineum anterius, is sometimes called the Sinus
Pudoris; it is broader above than below, and contains
several other parts.
On separating the labia, we see, immediately below
the superior commissure,
The Clitoris, a red projecting body, situated be-
low the arch of the pubis, and partly covered by its
Prepuce: The prepuce is a fold of skin, continued
from the inner surface of the labia, so as to cover the
superior and lateral parts of the clitoris. — The clitoris
resembles the penis of the male, and consists of two
cavernous bodies; these cannot, however, be traced in
this stage of the dissection. That part of the body
which forms an obtuse projection externally, is called
the Glans.
The Perineum Anterius is that portion of the soft
parts which extends from the inferior commissure of
the labia to the anus.
The Perineum Posterius is the space betwixt the
anus and point of the os coccygis.
The Nvmpile are two prominent doublings of the
integuments, extending from the glans of the clitoris to
the sides of the vagina. Their external side is con-
GUIDE TO ANATOMY. 61
tinued from the inner surface of the labia, and from
the prepuce of the clitoris, while their internal surface
seems immediately continued from the fine, thin, vas-
cular integuments covering the clitoris itself; they are
spongy, and consist internally of cellular and adipose
substance.
A little lower we see the orifice of the urethra; it is
situated below the clitoris and arch of the pubis, be-
twixt the nymphae, and above the orifice of the vagina:
it consists of a small rising prominence like a pea, in
the centre of which is a small opening or hole.
On each side of the orifice of the urethra, we meet
generally with the orifices of two mucous glands, which
by some are named Cowper"s Glands of the female.
On separating the lower part of the labia pudendi,
we see the Vestibulum. a space which leads to the
vagina; it is bounded behind, by the carunculs mvrti-
formes, or by the hymen in virgins; on the sides, by
the labia; .before, by the perineum anterius, which pro
jects forwards, forming a kind of valve, so that a little
pit is formed behind it, which is termed Fossa Navi-
cularis, or Scaphoides.
The Hymen*, or Circulus Membranosus, is a thin
and extensile membrane, formed by a doubling of the
inner surface of the vestibulum and lower part oi the
vagina, the entrance of which is by its means much
contracted in virgins. It generally has an opening in
its upper part, but it is completely ruptured in the first
coitus: its form is various, frequently semilunar, and
then its base is attached to the vestibulum, while its
cornua extend upwards as far as the sides of the
urethra.
After the destruction of the hymen, in married
women, we see some irregular projections marking
the orifice of the vagina, and termed Caruncul.t.
Myrtiformes: they are srenerally supposed to be
6
62 LONDON DISSECTOR, OR
the remains of the hymen, but are not exactly in the
same situation.
Behind these is the Vagina, or canal leading to the
uterus; at the extremity of which may be felt project-
ing the Os Internum Uteri, or Os Tince, but it
cannot be seen without dissection.
The skin should now be divided on the side of the
right labium, and the dissection should be carried from
the groin to the side of the anus; the cellular membrane
must be carefully removed, in order to expose the
following parts.
We find the Clitoris consisting of two spongy
bodies termed Crura, which unite and form the body.
The crus of each side is a cavernous body, arising
from the ramus and upper part of the tuberosity of the
ischium, continued along the ramus of the os pubis,
and uniting with its fellow opposite to the symphysis
pubis. The body formed by the crura does not extend
upwards, but forms a curve downwards towards the
urethra; it is divided internally by the Septum Pec-
tiniforme, and is attached to the spmphysis pubis by
a suspensory ligament: it is invested by a ligamentous
membrane.
The muscles which are met with in this dissection
consist of four pair, and two single muscles.
The Erector Clitoridis,
transversus periniei,
Levator Ani,
Coccygeus,
The Sphincter Ani, ~) . • , J ,
a \t , r two single muscles.
Sphincter Vaginae, 3
1. The Erector Clitoridis arises, fleshy and
tendinous, from the tuber ischii, from the inside of the
ramus of the os ischium, and from the ramus of the os
pubis: It passes over the crus of the clitoris, and be-
coming tendinous, is lost upon it.
on each side.
GUIDE TO, ANATOMY. 63
Arising from the same point, and surrounded by
much cellular membrane, we find,
2. The Trans versus Perinjei. — Its origin is the
same as in the male.
It is inserted into a ligamentous substance in the pe-
rineum antenus, at the point where the sphincter ani
and sphincter vaginae meet.
This ligamentous or tendinous substance deserve>
attention. Here, as in the male, it is the point of union
into which different muscles are inserted.
This muscle serves to sustain the perineum.
3. Surrounding the extremity of the vagina, and a
small part of the vestibulum, we find the Sphincter
V agi>\e; it arises anteriorly, from the crura of the cli-
toris on each side; it surrounds the orifice of the vagi-
na, and is
Inserted into the ligamentous point of the perineum,
where the fibres of each side meet, and are connected
with those of the transversi perinaei, and with the
sphincter ani.
It contracts the mouth of the vagina, and compresses
the plexus retiformis. -
4. The Sphincter Ani exactly resembles the same
muscle in the male.
5. The Levator Ant resembles the same muscle
of the male; it surrounds the sides of the vagina in part,
and consequently assists in constricting and supporting
it
6. The Coccygeus is longer than in the male, from
the greater transverse diameter of the inferior aperture
of the pelvis.
Under the fibres of the sphincter vaginae, you will
find the Plexus Retiformis, or Corpus Caverno-
sum Vaginae, a spongy body, consisting of cellular
substance, interwoven with a number of convoluted
blood-vessels; it arises from the sides of the clitoris,
passes on each side of the extremity of the vagina, is
64 LONDON DISSECTOR, OR
not continued completely around it, but is lost on its
posterior part.
The Vagina is the canal leading from the vestibu-
lum to the uterus. It lies betwixt the rectum and
inferior surface of the urethra and bladder, and is
connected to them by cellular membrane. It is com-
posed of fibrous substance, partly ligamentous, and
perhaps in part muscular; its inner surface is rugose,
vascular, and occupied by mucous glands. On slitting
it up, we see, at its posterior extremity, the Os Uteri,
a rounded projection, with a transverse fissure.
The Uterus, or Womb. — This organ is best seen
from the cavity of the abdomen. It is situated betwixt
the bladder and rectum, to both of which it is con-
nected by reflections of peritoneum; it is of the shape
of a pear, somewhat flattened, inwardly hollow, out-
wardly of a whitish color, and of a firm consistence.
The broad upper part of the womb is called the Fun-
dus Uteri, the narrower part is named the neck, or
Cervix Uteri, and the intermediate part its Body.
The uterus has four ligaments, two on each side:
1. The Ligamentum teres, or Round Ligament.
It is a round long cord, extending from the side of the
fundus uteri, and passing through the abdominal ring,
to be lost in the groin.
The Ligamentum Latum, or Broad Ligament, is
a broad fold of peritoneum, reflected from the body of
the uterus, and connecting it on the sides of the pelvis.
The uterus, together with its two broad ligaments,
divides the pelvis into an anterior and posterior half;
in the former of which is the bladder, and in the latter
the rectum. The duplicature of the broad ligament
encloses the Fallopian tube, ovary, and round liga-
ment.
The Fallopian Tubes are two. Each tube is con-
tained in the upper part of the doubling of the broad
ligament; it goes out from the fundus of the womb, and
GUIDE TO ANATOMY. 65
is a slender hollow tube: its outer end is curved down-
wards and backwards, and terminates by a broad
fringed extremity, termed Morsus Diaboli, or the
Fimbriae. This broad extremity is connected to the
next pair of organs.
The Ovaria are two small oval bodies, white and
flat, situated by the sides of the uterus, and inclosed
in the posterior fold of the broad ligament behind the
Fallopian tube; each ovarium is connected to the fun-
dus uteri by a short and round ligament.
The Bladder is situated before the uterus, and is
described in the preceding chapter.
The Urethra is short in females, and near the
bladder is surrounded by a spongy fleshy substance,
is connected to the cartilaginous arch of the pubis by
the ligamentum inferius vesicae.
The Ureter descends from the kidneys over the
psoas muscle; it runs for some space betwixt the blad-
der and vagina, and at last perforates the bladder near
the neck.
The Rectum lies behind the uterus. See the pre-
ceding chapter.
To obtain a more satisfactory knowledge of the
relative situation of the parts, the left side of the pelvis
should be removed as in the male, and the parts exam-
ined in that situation.
CHAPTER. IV.
DISSECTION OF THE THIGH
SECTION. I.
OF THE ANTERIOR PART OF THE THIGH.
Of the Fascia, cutaneous vessels, and nerves.
Beneath the integuments, you will find a strong
fascia, or aponeurotic expansion, investing the whole
thigh, called the Fascia Lata Femoris. It consists
partly of tendinous, partly of ligamentous fibres; sur-
rounds and covers all the muscles, and sends septa or
partitions between them: — It is very strong, smooth,
and tendinous on the outer part of the thigh-, but, on
the anterior and inner part, it is very thin, and of a
cellular texture. Consequently to demonstrate the
whole extent of this fascia, it should be first exposed
on the outside of the thigh, and the dissection continued
carefully inwards on the fore-part, where it is with
difficulty distinguished from the common cellular mem-
brane.
But, in removing the common integuments from the
fore part of the thigh, it will be proper to attend to
some parts which are situated above the fascia.
1 . The Vena Saphena Major is seen running up
on the inside of the knee and thigh. At first it lies
very superficial, betwixt the skin and fascia. As it
ascends, it is gradually enveloped by the fibres of the
fascia, and then sinks beneath it to join the femoral
GUIDE TO AXATOMY. 67
vein about an inch below Poupart's ligament, receiv-
ing in its course, several cutaneous veins.
2. Immediately under the true skin, and more
superficial than the veins or nerves, you may occa-
sionally perceive the Lymphatic Vessels running,
like lines of a whitish colour, to enter the inguinal
glands: they are more numerous qn the fore part, than
on the outside of the thigh.
3. Several Cutaneous Nerves proceeding from
the lumbar or anterior crural nerve, are seen ramifying
above the fascia.
The fascia may now be exposed distinctly. Observe
how extensively it arises from the bones, tendons,
and ligaments. On the anterior and superior part
of the thigh, it arises from Poupart's ligament,* from
the os pubis, the descending ramus of that bone, and
the ascending ramus and tuberosity of the ischium; —
behind, and on the outside, from the whole spine of
the ilium, and from the sacro-sciatic ligaments. It
receives a number of fibres from a muscle belonging
to it, viz.: the tensor vaginae femoris, and from the
tendon of the gluteus maximus; — passing down over
the whole thigh, it is firmly fixed to the linea aspera,
the condyles of the femur, and the patella, and is con-
tinued over the knee, to be attached to the heads of
the tibia and fibula, and form the fascia of the leg.
On the upper and anterior part of the thigh, there
is a slight hollow, where the great vessels descend
under the crural arch. The fascia lata forms just on
the outside and upper part of this, a crescent-shaped
fold, called its semilunar edge, which is strongly con-
nected to the crural arch, and sometimes contributes
to the strangulation in femoral hernia.
* At this part the fa-cia of the thigh is carered by a more superficial
expansion, which lies over the lower part of the aponeurosis ofthe ex-
ternal oblique muscle, completely covers the crural arch, and descend*
some little way beyond the bend of the thigh. It has been called the
superficial fascia.
68 LONDON DISSECTOR, OR
The fascia should now be dissected back; and, in
lifting up the thicker part of it, which covers the
outside of the thigh, you may observe that it is com-
posed of two laminae of fibres, the fibres of the outer
lamina run in circles round the thigh, while those on
the inner, stronger, and more firmly connected, run
longitudinally.
The muscles on the anterior part of the thigh
are nine in number.
1. The Tensor Vaginae Femoris — Arises, by a
narrow, tendinous, and fleshy origin, from the external
part of the anterior superior spinous process of the os
ilium: it forms a considerable fleshy belly, and ex-
tending downwards and backwards, is
Inserted into the inner lamina of the great fascia,
where it covers the outside of the thigh, and a little
below the trochanter major.
This muscle, called also the Fascialis, serves to
stretch the great fascia of the thigh, to assist in the
abduction of the thigh, and in its rotation inwards.
2. The Sartorius — Arises, by short tendinous
fibres, from the anterior superior spinous process of
the os ilium, soon becomes fleshy, extends obliquely
across the thigh, and passes behind the inner condyle.
Inserted, by a broad and thin tendon, into the inner
side of the tibia, immediately below its anterior
tubercle.
This muscle lies before the muscles of the thigh,
crossing them like a strap about two inches in breadth,
and serves to flex the leg obliquely inwards on the
thigh, and to bend the thigh forwards.
3. The Rectus Femoris — Arises, by a strong
tendon, from the inferior anterior spinous process of
the os ilium; and, by another strong tendon, from
the dorsum of that bone a little above the acetabulum,
and from the capsular ligament of the hip-joint. The
two tendons soon unite, and send off a large belly,
GUIDE TO ANATOMY. 69
which runs down over the anterior part of the thigh,
forming a complete peniform muscle, and terminates
in a flat but strong tendon, which is
Inserted into the upper extremity of the patella;
where a thin aponeurosis is sent from it over the fore
part of that bone, to terminate on the strong ligament
which connects the lower part of the patella to the
tibia, and is called Ligamentum Patellae.
It serves to extend the leg on the thigh, to bend
the thigh on the pelvis, and to bring the pelvis and
thigh forwards on the leg.
Under the rectus, and partly covered by it, there is
a large mass of flesh, which, at first sight, appears to
form but one muscle. It may, however, be divided
into three; the separation on the external surface is
not generally very evident, but, by following the
course of the vessels which enter this mass, and by
cutting through perhaps a few fibres externally, you
will discover the line of separation, and this separa-
tion, as you proceed deeper with your dissection,
will become very distinct. The three muscles are
named vastus externus, vastus internus, and crurseus:
at the upper and middle parts of the thigh, they may
be separated very distinctly; but for two or three inches
above the condyles, they are inseparably connected.
4. The Vastus Externus — Arises, tendinous and
fleshy, from the anterior surface of the root of the
trochanter major, from the outer edge of the linea
aspera, its whole length, — from the oblique line run-
ning to the external condyle, — and from the whole
external flat surface of the thigh bone. The fleshy
fibres run obliquely forwards.
Inserted into the external surface of the tendon of
the rectus cruris, and into the side of the patella: —
Part of its ends likewise in an aponeurosis which
passes over the side of the knee to the leg, and is
70 LONDOM DISSECTOR, OR
firmly fixed to the head of the tibia, closely adhering
to the capsule of the knee-joint.
It extends the leg, or brings the thigh forward upon
the leg.
5. The Vastus Internus — Arises, tendinous and
fleshy, from the fore-part of the root of the trochanter
minor, from all the upper edge of the linea aspera
from the oblique line running to the inner condyle,
and from the whole internal surface of the thigh bone.
Its fibres descend obliquely downwards and forwards.
Inserted into the lateral surface of the tendon of the
rectus cruris, and into the side of the patella; it also
sends off an aponeurosis, which is continued down to
the leg, and covers the inner part of the capsule of
the knee.
6. The Crur^us, or Crulalis. — The principal
part of this muscle is lapped over, and concealed, by
the bellies of the two vasti; and the small part, which
is seen projecting between the anterior edges of those
muscles, lies behind the belly of the rectus cruris.
Arises, fleshy, from between the two trochanters of
the os femoris, from all the fore-part of the bone, and
from the outside as far back as the linea aspera; but
from the inside of the bone it does not arise, for be-
tween the forepart of the femur and the inner edge of
the linea aspera, there is a smooth plain surface, of the
breadth of an inch, extending nearly the whole length
of the bone, from which no muscular fibres arise.
Inserted into the posterior surface of the tendon of
the rectus, and the upper edge of the patella.
7. The Gracilis arises, by a broad thin tendon,
from the lower half of that part of the os pubis which
forms the symphysis, and from the inner edge of the
descending ramus: — It soon grows fleshy, and forms a
belly, which becoming narrower as it descends; termi-
nates in a tendon, which passes behind the inner con-
GUIDE TO ANATOMY. 71
dvle of the thigh bone, and is reflected forwards, to
be
Inserted in the inside of the tibia below the tendon
of the sartorius, and above that of the semitendinosus.
It serves to bring the thigh inwards and forwards,
and assists in bending the leg.
8. The Pectinalis — Arises, fleshy from that ridge
of the os pubis which forms the brim of the pelvis, and
from the concave surface beiow the ridge. It forms
a thick flat belly,
Inserted, by a flat tendon into the linea aspera, im-
mediately below the less trochanter.
Its origin lies on the inside of the belly of the psoas
magnus, where that muscle slides over the brim of the
pelvis, and on the outside of the origin of the adductor
longus. It bends the thigh forwards, moves it inwards,
and performs rotation, by turning the toes outwards.
9. The Triceps Adductor Femoris consists of
three distinct muscles, which, passing from the pelvis
to the thigh, lie in different layers upon one another,
and have nearly the same action.
( 1 . ) The Adductor Longus, or Primus — Arises,
by a short strong tendon, from the upper and fore part
of the os pubis, near its symphysis; — forms a large
triangular belly, which, as it descends, becomes broad-
er, but less thick.
Inserted, tendinous, into the middle part of the linea
aspera, occupying rather more than one-third of its
length.
(2.) The Adductor Brevis, or Secuxdus — Ari-
ses, fleshy and tendinous, from the os pubis, between
the lower part of the symphysis pubis, and the fora-
men thyroideum: — it forms a fleshy belly,
Inserted, tendinous, into the upper third of the linea
aspera, that is, from the root of the less trochanter to
the commencement of the insertion of the next muscle.
72 LONDON DISSECTOR, OR
(3.) The Adductor MAGNus,or Tertius. — Arises,
principally fleshy, from the lower part of the body and
the descending ramus of the os pubis, and from the as-
cending ramus of the ischium, as far as the tuberosity
of that bone. The fibres run outwards and down-
wards, having various degrees of obliquity.
Inserted, fleshy, into the whole length of the linea
aspera, into the oblique ridge above the internal con-
dyle of the os femoris, and, by a roundish long tendon,
into the upper part of that condyle.
This large muscle arises behind and below the two
other adductors; it forms a flat partition betwixt the
muscles on the fore and back parts of the thigh.
All these muscles serve to approximate the thighs
to each other, and to roll them outwards. The two
anterior heads will bend the thigh; the posterior will
extend it, if it be bent forwards.
SECTION II.
OF THE POSTERIOR PART OF THE THIGH.
Of the fascia.
Aeove that part of the great fascia which invests
the thigh posteriorly, we meet with several cutaneous
nerves. They are of little importance, taking their
origin either from the lumbar nerves, and passing over
the spine of the os ilium, or from the great sciatic
nerve, and emerging from the lower margin of the
gluteus maximus. Other twigs come from the sacral
nerves, and from the sciatic in its course down the
thigh.
The muscles situated on the posterior part of the
thigh are eleven.
GUIDE TO ANATOMY. 73
On removing the integuments and fascia from the
hip, we expose
1. The Gluteus Maximus. — It arises, fleshy, from
the posterior third of the spine of the os ilium, from
the whole lateral surface of the sacrum, below the
posterior spinous process of the ilium; from the back
part of the posterior or inferior sacro-sciatic liga-
ment,* over which the edge of this muscle hangs in a
folded manner, and from the lateral surface of the os
coccygis.
The fleshy fibres proceed obliquely forwards and
downwards, forming a thick broad coarse muscle, and
converging gradually, terminate in a strong flat tendon.
This tendon slides over the posterior part of the
trochanter major, sends off a great quantity of tendi-
nous fibres, to be inseparably joined to the fascia lata
of the thigh; and is
Inserted, into a rough surface at the upper and outer
part of the linea aspera, immediately below the tro-
chanter major; also very extensively into the fascia
lata, which covers the former insertion.
This muscle is quite superficial, covering all the
other muscles which are situated on the back part of
the hip, covering also the tuber ischii, and the ten-
dons of the muscles which arise from that projection.
It is used to restore the thigh, after it has been
bent; — to rotate it outwards; to extend the pelvis on
the thigh, and maintain it in that position in the erect
posture of the body.
* The sacro-sciatic ligaments are two in number; they pass between
the ischium and sacrum.
1. The external or inferior, or posterior, sacro-sciatic ligament arises
from the external edge of the transverse processes of the sacrum, descends
obliquely, and is inserted into the tuberosity of the os ischium.
•2. The internal, or anterior, arises from the edge of the transverse
processes of the sacrum, and of the os coccygis; it passes across on the
inside of the external, and is inserted into the point of the spinous process
of the ischium.
74 LONDON DISSECTOR, OR
By raising this muscle from its origin, we expose
2. The Gluteus Medius — Arises, fleshy, from
all the outer edge of the spine of the os ilium, as far
as the posterior tuberosity; from the dorsum of the
bone, between the spine, and semicircular ridge
(which passes from the anterior superior spinous pro-
cess to the ischiatic notch;) also from the rough surface
which extends from the anterior superior to the ante-
rior inferior spinous process, and from the inside of a
fascia which covers its anterior part. The fibres con-
verge into a strong and broad tendon, which is
Inserted into the upper and outer part of the great
trochanter.
The posterior part of the belly, and the tendon of
this muscle, are concealed by the gluteus maximus,
but the anterior and largest part is superficial, being
covered only by a fascia.
Having lifted up this muscle from its origin, you
will discover,
3. The Gluteus Minimus. — It is entirely con-
cealed by the gluteus medius, and between their ten-
dons there is a bursa mucosa.
It arises, fleshy, from the semicircular ridge of the
ilium, and from the dorsum of the bone below the
ridge within half an inch of the acetabulum. Its
fibres run in a radiated direction towards a strong
tendon, which is
Inserted into the anterior and superior part of the
great trochanter.
4. The Pyriformis — Arises, within the pelvis, by
three tendinous and fleshy origins, from the second,
third, and fourth false vertebrae or 'divisions of the
sacrum. It forms a thick belly, which passes out of
the pelvis, below the niche in the posterior part of
the ilium, (from which it receives a few fleshy fibres,)
and above the superior sacro-sciatic ligament.
GUIDE TO ANATOMY. 75
Inserted, by a roundish tendon, into the uppermost
part of the cavity at the root of the trochanter major.
Like the other small muscles of the hip, it is entirely
concealed by the gluteus maximus; its belly lies behind
and below the gluteus medius, but is not at all covered
by it, and above the superior gemellus. Sometimes
the pyriformis is divided into two distinct muscles, by
a branch of the great sciatic nerve.
It moves the thigh a little upwards, and rolls it
outwards.
o. The Gemini consist of two heads which are
distinct muscles.
(1.) The superior arises from the back part of the
spinous process of the ischium.
(2.) The inferior from the upper part of the tube-
rosity of the os ischium, and the anterior surface of
the posterior sacro-sciatic ligament.
Inserted, tendinous and fleshy, into the cavity at the
root of the trochanter major, immediately below the
insertion of the pyriformis, and above the insertion of
the obturator externus.
They lie below the pyriformis, and above the quad-
ratus femoris-, they are united by a tendinous and
fleshy expansion, which forms a purse or sheath for
the tendon of the obturator internus.
They serve to roll the thigh outwards, and to bind
down the tendon of the obturator internus.
Lying between the bellies of the gemini, you will
perceive,
6. The Obturator Internes, once called mar-
supialis. — It arises, tendinous and fleshy, from more
than one-half of the internal circumference of the fora-
men thyroideum, and from the inner surface of the
ligament which fills up that hole; its inside is covered
by a portion of the levator ani; it forms a flattened
tendon, which passes out of the pelvis in a sinuosity
76 LONDON DISSECTOR, OR
betwixt the spinous process and tuberosity of the
ischium; and, becoming rounder, is
Inserted into the pit at the root of the trochanter
major.
Its origin lying within the pelvis, cannot be exposed
till the contents of that cavity are removed.
7. The Quadratus femoris — Arises, tendinous and
fleshy, from an oblique ridge, which descends from
the inferior edge of the acetabulum along the body of
the ischium, between its tuberosity and the foramen
thyroideum: its fibres run transversely, to be
Inserted^ fleshy, into a rough ridge on the back part
of the femur, extending from the root of the greater
trochanter to the root of the less.
Situation: It is concealed by the gluteus maximus,
lies below the inferior head of the gemini, and above
the superior fibres of the adductor magnus; its origin
is in contact with the origin of the hamstring muscles.
It rolls the thigh outwards.
On lifting up the quadratus femoris from its origin,
and leaving it supended by its insertion, you discover,
running in the same direction, the strong tendon of,
8. The Obturator Externus. — This muscle
arises, fleshy, from almost the whole circumference of
the foramen thyroideum, and from the external surface
of the obturator ligament; its fibres pass outwards
through the notch placed between the inferior margin
of the acetabulum and the tuberosity of the ischium,
wind around the cervix of the os femoris, adhering to
the capsular ligament, and terminate in a strong
tendon, which is
Inserted into the lowermost part of the cavity, at the
root of the trochanter major, immediately below the
insertion of the inferior head of the gemini.
This muscle cannot be distinctly seen, until all the
muscles which run from the pelvis to the upper part
GUIDE TO ANATOMY.
77
of the thigh are removed, both on the fore and back
part.
It rolls the thigh bone obliquely outwards.
9. The Biceps Flexor Cruris — Arises by two dis-
tinct heads; the first, called the Long Head, arises in
common with the semitendinosus, by a short tendon,
from the outer part of the tuberosity of the ischium, and,
descending, forms a thick fleshy belly. The second,
termed the Short Head, arises, tendinous and
fleshy, from the linea aspera, immediately below the
insertion of the gluteus maximus; and from the oblique
ridge running to the outer condyle, where it is con-
nected with the fibres of the vastus externus. The
two heads unite at an acute angle, a little above the
external condyle, and terminate in a strong tendon
which is
Inserted into a rough surface on the outside of the
head of the fibula.
The biceps cruris, as it is called, bends the leg, and
particularly by means of its short head twists the leg
outwards in the bent state of the knee.
10. The Semitendinosus — Arises, tendinous, in
common with the long head of the biceps, from the tu-
berosity of the ischium; it has also some fleshy fibres
arising from that projection more outwardly: — as it de-
scends, it arises, for two or three inches, fleshy, from
the inside of the tendon of the biceps; forms a thick
belly, and terminates at the distance of three or four
inches from the knee in a long round tendon, which be-
coming flat, passes behind the head of the tibia, and is
reflected forwards, to be
Inserted into the anterior angle of that bone, some
little way below its tubercle, and below the tendon of
the gracilis. The belly of this muscle is intersected,
about its middle, by a narrow transverse tendinous line.
It bends the leg backwards, and slightly inwards.
78 LONDON DISSECTOR, OR
1 1 . The Semimembranosus — Jlrises, by a strong-
round tendon, from the upper and outer part of the tu-
berosity of the ischium; the tendon, soon becoming
broader, sends off obliquely a fleshy belly; this muscle
is continued, fleshy, much lower down than that last
described. The fleshy fibres terminate obliquely in
another flat tendon, which passes behind the inner con-
dyle, sends off a thin aponeurotic expansion under the
inner head of the gastrocnemius, to cover the posterior
part of the capsule of the knee-joint, and to be affixed
to the external condyle: the tendon then becoming
rounder, is
Inserted into the inner and back part of the head of
the tibia.
This is a semi-penniform muscle; and serves to bend
the leg backwards.
The last two muscles properly form the inner ham-
string; but some enumerate among the tendons of the
inner hamstring, the sartorius and gracilis.
CHAPTER. V.
DISSECTION OF THE LEG AND FOOT.
SECTION I.
OF THE FORE PART OF THE LEG AND FOOT.
On dissecting off the integuments from the fore part
of the leg, we find a strong fascia continued from the
thigh; it adheres firmly to every projecting point of
bone, to the head and spine of the tibia, and to the
fibula; it grows thinner towards the lower part of the
leg; but where it passes over the ankle, it again be-
comes very strong by its adhesions to the outer and
GUIDE TO ANATOMY. 79
inner ankle, and forms a strong Annular or Trans-
verse Ligament, which binds down the tendons, and
is evidently but a thicker and stronger part of the
a:eneral fascia of the les:. This annular lisament seems
to consist of two distinct cross bands, which, going
from the point of the outer ankle and neighboring part
of the os calcis, are fixed to the malleolus internus,
and to the inside of the os naviculare.
Before removing the fascia, it will be proper to
remark.
1 . The vena saphena major, running upon the inside
of the tibia, and accompanied by a cutaneous nerve,
the nervus saphenus.
2. Several cutaneous nerves, branching on the outer
and fore-part of the leg and foot, and derived from the
nervus peroneus.
The fascia should then be dissected off; and, in
doing this, remark, that it is firmly attached to the
bones, and also to the bellies of the muscles at the
upper part of the leg, so that their surfaces appear
ragged, where the fibres are separated which arose
from the inside of the fascia: Remark also, that it
sends down processes between the muscles; these are
named intermuscular ligaments, or tendons; they give
origin to the fibres of all the muscles betwixt which
they pass, connecting them together inseparably, so
that the dissection is difficult, and has a rough appear-
ance.
MUSCLES SITUATED ON THE FORE PART AND OUT-
SIDE OF THE LEG.
These are six in number.
1. The Tibialis Anticus — Jlrises, principally
fleshy, from the exterior surface of the tibia, from its
anterior angle or spine, and from nearly half of the
interosseous ligament; from these surfaces it continues
80 LONDON DISSECTOR, OR
to arise down two-thirds of the length of the bone;
also from the inner surface of the fascia of the leg,
and from the intermuscular ligaments. The fleshy
fibres descend obliquely, and terminate in a strong
tendon, which crosses from the outside to the fore-part
of the tibia, passes through a distinct ring of the
annular ligament near the inner ankle, runs over the
astragulus and os naviculare, and is
Inserted into the upper and inner part of the os
cuneiforme internum, and the base of the metatarsal
bone supporting the great toe.
It draws the foot upwards and inwards; or, in other
words, bends the ankle-joint.
2. Extensor Longus Digitorum Pedis — Arises,
tendinous and fleshy, from the outer part of the head
of the tibia; from the head of the fibula; from the
anterior angle of the fibula almost its whole length;
and from part of the smooth surface between the
anterior and internal angles; from a small part of the
interosseous ligament; from the fascia and intermus-
cular ligaments.
Below the middle of the leg, it splits into four round
tendons, which pass under the annular ligament,
become flattened, and are
Inserted into the root of the first phalanx of each of
the four small toes, and expanded over the upper side
of the toes as far as the root of the last phalanx.
This muscle also runs entirely superficial; it lies
between the tibialis anticus "and peroneous longus,
being firmly connected to them by intermuscular liga-
ments; but, at the lower part of the leg, it is separated
from the tibialis anticus by the extensor pollicis lon-
gus, and from the peroneus longus by the peroneus
brevis.
It extends all the joints of the four small toes; and
"bends the ankle joint.
GUIDE TO ANATOMY. 81
3. Peroneus Tertius — Arises, fleshy, from the
anterior angle of the fibula, and from part of the
smooth surface between the anterior and internal
angles, extending from below the middle of the bone
downwards to near its inferior extremity; — sends its
fleshy fibres forwards to a tendon, which passes under
the annular ligament in the same sheath as the extensor
digitorum longus, and is
Inserted into the base of the metatarsal bone that
supports the little toe.
The belly of this muscle is inseparably connected
with the extensor longus digitorum, and is properly
its outer part; it lies between that muscle and the
peroneus brevis. The tendon runs down on the out-
side of that tendon of the extensor longus digitorum
which goes to the little toe. The whole of the muscle
is superficial.
4. Extensor Proprius Pollicis Pedis — Arises^
tendinous and fleshy, from part of the smooth surface
between the anterior and internal angles of the fibula,
and from the neighbouring part of the interosseous
ligament, extending from some distance below the
head of the bone to near its inferior extremity; a few
fibres also arise from the lower part of the tibia;
the fibres pass obliquely downwards and forwards
into a tendon, which, inclining inwards, passes over
the fore-part of the astragalus and os naviculare, and
over the junction of the os cuneiforme internum and os
cuneiforme medium, to be
Inserted into the base of the first and of the second
phalanges of the great toe.
This is a very slender muscle; its belly is concealed
between the tibialis anticus and extensor digitorum
longus,, and cannot be seen till those muscles are
separated from one another; — the tendon is superficial,
running between the tendons of those two muscles.
82 LONDON DISSECTOR, OR
It serves to extend the great toe; and to bend the
ankle.
The Peroneus Longus — Arises, tendinous and
fleshy, from the fore-part and outside of the head of
the fibula, and from the adjacent part of the tibia,
from the external angle of the fibula, and from the
smooth surface between the anterior and external
angles as far down as one-third of the length of the
bone from its lower extremity; also from the fascia
of the leg and intermuscular ligaments. The fibres
run obliquely outwards into a tendon, which passes
behind the outer ankle, through a grove in the lower
extremity of the fibula: it is then reflected forwards
through a superficial fossa in the outside of the os
calcis, passes over a projection, runs in a groove in the
os cuboides, passes over the muscles in the sole of the
foot, and is
. Inserted, tendinous into the outside of the base of
the metatarsal bone that sustains the great toe, and
into the os cuneiforme internum.
The tendon of this muscle is superficial where it
crosses the outside of the os calcis, but in the sole of
the foot it is Concealed by the muscles situated there,
and will be seen in the dissection of that part.
It expends the ankle-joint, and turns the sole of the
foot outwards.
6. The Peroneus Brevis — Arises, fleshy from
the outer edge of the anterior angle of the fibula, and
from part of the smooth surface behind that angle;
beginning about one-third down the bone, and con-
tinuing its adhesion to near the ankle; from the fascia
of the leg, and from the intermuscular ligaments: —
The fibres run obliquely towards a tendon, which
passes through the groove of the fibula behind the
outer ankle, being there inclosed in the same ligament
with the tendon of the peroneus longus, then through
a separate groove on the outside of the os calcis, and is
GUIDE TO ANATOMY. 83
Inserted into the external part of the base of the
metatarsal hone that sustains the little toe.
This muscle arises between the extensor longus
digitorum and peroneus longus; its belly is overlapped,
and concealed by the belly of the peroneus longus;
but, as it continues fleshy lower down, it is seen,
above the ankle, projecting on each side of the tendon
of that muscle: — Below, it is separated from the
peroneus tertius by that projection of the fibula which
forms the outer ankle, and which is only covered by
the common integuments.
It has the same use as that of the peroneus longus.
MUSCLES ON THE UPPER PART OF THE FOOT.
Only one muscle is found in this situation.
Extensor Brevis Digitorum Pedis — Arises,
fleshy and tendinous, from the anterior and upper
part of the os calcis, from the os cuboides, and from
the astragalus; forms a fleshy belly, divisible into four
portions; these send off four slender tendons, which
are
Inserted, the first tendon, into the first phalanx of
the great toe; and the other three into all the small
toes, except the little one, uniting with the tendons of
the extensor digitorum longus, and being attached to
the upper convex surface of all the phalanges.
The belly of this muscle lies under the tendons of
the extensor digitorum longus and peroneus brevis; it
is not, however, concealed, but is seen projecting
behind and betwixt these tendons; it assists in form-
ing the tendinous membrane which invests the upper
surface of all the phalanges of the toes.
Its use is to extend the toes.
It is sometimes described as two muscles, the ex-
tensor brevis pollicis pedis, and extensor brevis digi-
torum pedis.
84 LONDON DISSECTOR, OR
SECTION II.
DISSECTION OF THE MUSCLES ON THE POSTERIOR
PART OF THE LEG.
The fascia investing the posterior part of the leg, is
much thinner and less strong than that on the fore part.
The muscles to he described are seven in number.
1 . The Gastrocnemius Externus, or Gemellus,
Arises, by two distinct heads: — The first, or Internal
Head, arises, tendinous, from the upper and back part
of the internal condyle of the os iemoris, and fleshy
from the oblique ridge over that condyle. The sec-
ond, or External Head, arises, in the same manner,
from the external condyle. Each of the heads forms
a fleshy belly, the fibres of which are oblique, passing
from a tendinous expansion which covers the posterior
surface of the muscle, to another tendinous expansion
which covers the anterior surface, or that surface
which lies nearest the bones. The two bellies, of
which the internal is much the larger, are separated
by a considerable triangular space, in which the pop-
liteal blood-vessels and nerves pass to the leg, but de-
scending, they unite a little below the knee-joint in a
middle tendinous line, and below the middle of the tibia
send off a broad flat tendon, which unites a little above
the ankle with the tendon of the soleus.
Reflect the two heads of the gastrocnemius from the
femoral condyles, and you will then expose,
2. The Soleus, or Gastrocnemius Internus —
which arises, by two origins or heads. The External,
which is by far the larger, arises, principally fleshy,
from the posterior surface of the head of the fibula, and
from the external angle of that bone, for two-thirds of
its length, immediately behind the peroneus longus.
The internal head, arises, fleshy, from an oblique ridge
GUIDE TO ANATOMY. 85
on the posterior surface of the tibia, just below the pop-
liteus, and from the inner angle of that bone, during the
middle third of its length. The two heads which are
at first separated by the posterior tibial artery and
nerve, unite immediately, forming a large belly, which,
covered by the tendon of the gastrocnemius, is continu-
ed, fleshy, to within a short distance of the ankle-joint;
a little above which, the tendons of the gastrocnemius
and soleus unite, and form a strong round tendon, named
the Tendo Achillis, which slides over the upper and
posterior part of the os calcis, where it is furnished
with a small bursa mucosa, to be
Inserted into a rough surface on the back-part of that
bone.
It serves to elevate the os calcis, and thereby to raise
the whole body, as a preparatory measure to its being
carried forward in progression; to carry the leg back-
wards on the foot when that is fixed; the gastrocnemi-
us, from its origin in the thigh, also bends the leg ou
the thigh.
By detaching the heads of the gastrocnemius, you
will expose,
3. The Plantaris. — This muscle arises, fleshy,
from the upper part of the external condyle of the fe-
mur and its oblique ridge, forms a pyramidial belly
about three inches in length, which adheres to the
capsule of the knee-joint, runs over the popliteus, and
terminates in a long, slender, thin tendon. This ten-
don passes obliquely inwards over the inner head of
the soleus, and under the gastrocnemius; emerges from
between those two muscles, where their tendons unite,
and then runs down by the inside of the tendo Achillis,
to be
Inserted into the posterior part of the os calcis, on
the inside of the insertion of the tendo Achillis, and
somewhat before it.
8
86 LONDON DISSECTOR, OR
The use of this muscle is not well understood: some
say that it serves to tuck up the capsule in the great
bendings of the knee-joint; others, that it assists the
gastrocnemii. '
4. The Popliteus — Arises, within the capsular
ligament of the knee, by a round tendon, from a deep
pit or hollow on the outer side of the external con-
dyle; adheres to the posterior and outer surface of the
external semilunar cartilage; passes, within the cavity
of the joint, over the side of the condyle to its back
part; perforates the capsular ligament, and forms a
fleshy belly, which runs obliquely inwards, being
covered by a thin tendinous fascia, to be
Inserted, broad, thin and fleshy, into an oblique
ridge on the posterior surface of the tibia, a little
below its head, and into the triangular space above
that ridge.
This muscle is concealed entirely by the gastroc-
nemius, it lies above the inner head of the soleus; and
is more deeply situated than the plantaris, which
crosses over it.
It bends the leg, and when bent, rolls it, so as to
turn the toes inwards.
The belly of the soleus should now be lifted, in
order to expose the deeply-seated muscles. A strong
membranous fascia is seen connecting and investing
them, which is to be removed.
5. The Flexor Longus Digitorum Pedis Per-
forans — Arises, fleshy, from the posterior flattened
surface of the tibia, between its internal and external
angles, below the attachment of the soleus, and con-
tinues to arise from the bone to within two or three
inches of the ankle; the fibres pass obliquely into a
tendon which is situated on the posterior edge of the
muscle. This tendon runs behind the inner ankle in
a groove of the tibia; passes under a strong ligament
which goes from the inner ankle to the os calcis, and
GUIDE TO ANATOMY. S7
having received a strong tendinous slip from the flexor
pollicis longus, divides about the middle of the sole
of the foot, into four tendons, which pass through the
slits in the tendons of the flexor digitorum brevis, and
are
Inserted into the extremity of the last joint of the
four toes.
This muscle lies on the inside of the flexor longus
pollicis, and serves to bend the last joint of the toes,
and to assist in extending the foot.
6. Flexor Longus Pollicis Pedis — Arises,
fleshy, from the posterior flat surface of the fibula,
continuing its origin from some distance below the
head of the bone to within an inch of the ankle. The
fleshy fibres terminate in a tendon, which passes behind
the inner ankle through a groove in the tibia; next
through a groove in the astragalus, crosses in the sole
of the foot the tendon of the flexor longus digitorum,
to which it gives a slip of tendon; passes between the
two sesamoid bones, and is
Inserted into the last phalanx of the great toe.
Its office is to bend the last joint of the great toe,
and, being connected by a cross slip to the flexor
digitorum communis, to assist in bending the other
toes.
7. The Tibialis Posticus — Arises, fleshy from the
posterior surface of both the tibia and fibula, imme-
diately below the upper articulation of these bones
with each other; from the whole of the interosseous
ligament; from the angles of the bones to which that
ligament is attached; and from the flat surface of the
fibula behind its internal angle for more than two-thirds
of its length. The fibres run obliquely towards a
middle tendon, which, becoming round, passes behind
the inner ankle through a groove in the tibia.
Inserted into the upper and inner part of the os
naviculare, being further continued through a groove in
88 LONDON DISSECTOR, OR
that bone to the internal and external cuneiform bones;
it also sends some tendinous filaments to the os calcis,
the os cuboides, and the bases of the metatarsal bones
supporting the second and middle toe.
This muscle may be said to arise from the tibia and
fibula before the interosseous ligament, as its fibres
fill up a perforation in the upper extremity of that
ligament. The belly is concealed at its lower part
by the flexor longus digitorum and flexor pollicis, and
cannot be seen till those muscles are separated. It
extends the foot, and turns it inwards.
SECTION III.
DISSECTION OF THE SOLE OF THE FOOT.
The cuticle on the sole of the foot from constant pres-
sure is very much thickened; betwixt the integuments
and plantar aponeurosis, we find a tough granulated
fat, which adheres firmly to the aponeurosis, and is
dissected off with difficulty.
Aponeurosis, or Fascia Plantaris, is a very strong,
tendinous expansion, which arises from the projecting
extremity of the os calcis, and passes to the root of the
toes, covering and supporting the muscles of the sole
of the foot. Where it arises from the heel, it is thick,
but narrow; as it runs over the foot, it becomes broad-
er and thinner; and it is fixed to the the head of each
of the metatarsal bones by a bifurcated extremity, which
by its splitting, leaves room for the tendons, &c. to pass.
It seems divided into three portions, which are con-
nected by strong fasiculi of tendinous fibres; and fibres
are sent down, forming perpendicular partitions among
the muscles, and separating them into three classes;
GUIDE TO ANATOMY. 89
1. The middle portion, which is the largest, and
under which are contained the flexor brevis digitorum,
and the tendons of the flexor longus and lumbricales.
2. The external lateral portion, which covers the
muscles of the little toe.
3. The internal lateral portion concealing the mus-
cles of the great toe.
On removing the plantar aponeurosis, the first order
of muscles in the sole of the foot is exposed: it consists
of three muscles.
Abductor Pollicis, situated on the side of the great
toe.
Abductor Minimi Digiti, on the side of the little toe.
Flexor Brevis Digitorum Pedis, the mass in the mid-
dle, situated between the two abductors.
1. Abductor Pollicis Pedis — Arises, tendinous
and fleshy, from the lower and inner part of the os
calcis; from a ligament which extends from the os cal-
cis to the os naviculare; from the inside of the osnavi-
culare and cuneiforme internum; and from the fascia
plantaris.
Inserted, tendinous, into the internal sesamoid bone,
and base of the first phalanx of the great toe.
It moves the great toe from the rest.
2. Abductor Minimi Digiti Pedis — Arises, tendi-
nous and fleshy, from the outer side of the os calcis:
and from a strong ligament, which passes from the os
calcis to the metatarsal bone of the little toe; also from
the fascia plantaris.
Inserted, tendinous, into the base of the metatarsal
bone of the little toe, and into the outside of the base
of the first phalanx.
This muscle can frequently be divided distinctly into
two portions.
It moves the little toe from the rest.
3. Flexor Brevis Digitorum Pedis Perfora-
tus — Arises, fleshv, from the anterior and inferior part
8*
90 LONDON DISSECTOR, OR
of the protuberance of the os calcis, and from the
inner surface of the fascia plantaris; also from the ten-
dinous partitions betwixt it and the abductors of the
great and little toe: — it forms a thick fleshy belly, and
sends off four tendons, which split for the passage of the
tendons of the flexor longus digitorum, and are
Inserted into the second phalanx of the four lesser
toes.
The tendon of the little toe is often wanting.
Its use is to bend the second joint of the toes.
The muscles of this order are quite superficial, being
only covered by the fascia plantaris.
These being removed, or lifted from their origins,
and left hanging by their tendons, the second order is
exposed.
1 . The tendon of the Flexor longus digitorum pedis
is seen coming from the inside of the os calcis; and,
having reached the middle of the foot, dividing into its
four tendons, which pass through the slits of the ten-
dons of the flexor digitorum brevis, and are inserted
into the base of the last phalanx of the four toes.
2. The tendon of the Flexor longus pollicis is seen
crossing under* the tendon of the flexor longus digito-
rum, and, having given to it a short slip of tendon, pro-
ceeding between the two sesamoid bones to the base of
the last phalanx of the great toe.
3. Flexor Digitorum Accessorius, or Massa
Carnea Jacobi Sylvii — Jlrises, fleshy, from the sinu-
osity at the inside of the os calcis, and, tendinous,
from that bone more outwardly: — it forms a belly of
a square form.
Inserted into the outside of the tendon of the flexor
digitorum longus, just at its division.
It assists the flexor longus.
* In the erect posture, it crosses above, lying nearer to the metatarsal
bones than that tendon; but in the description, the sole of the foot is sup-
posed to be placed uppermost.
GUIDE TO ANATOMY. 91
4. Lumbricales Pedis — Arise, by four tendinous
and fleshy beginnings, from the tendons of the flexor
longus digitorum, immediately after their division.
Inserted, by four slender tendons, into the inside of
the first phalanx of the four small toes, and into the
tendinous expansion that is sent from the extensors to
cover the upper part of the toes.
They serve to promote the flexion of the toes, and
to draw them inwards.
The second order of muscles being removed, we
expose the third order.
1. Flexor Brevis Pollicis Pedis. — It arises, ten-
dinous, from the under and fore part of the os calcis,
where it joins with the os cuboides: also from the
os cuneiforme externum; it forms a fleshy belly,
which is connected inseparably to the abductor and
adductor pollicis.
Inserted, by two tendons, into the external and inter-
nal sesamoid bones; and it is continued on into the
base of the first phalanx of the great toe. It bends
the first joint of the great toe.
2. Adductor Pollicis Pedis — Arises, tendinous
and fleshy, from a strong ligament which extends
from the os calcis to the os cuboides, and from the
roots of the second, third, and fourth metatarsal
bones; it forms a fleshy belly, which seems at its
beginning divided into two portions.
Inserted, tendinous, into the external sesamoid bone,
and root of the matatarsal bone of the great toe.
Used to bring this toe nearer the rest.
3. Flexor Brevis Minimi Digiti Pedis — Arises,
tendinous and fleshy, from the os cuboides, and from
the root of the metatarsal bone of the little toe.
Inserted, tendinous, into the base of the first pha-
lanx of the little toe, and into the anterior extremity
of the metatarsal bone. Used to bend this toe.
Transversalis Pedis — Arises, tendinous, from
92 LONDON DISSECTOR, OR
the anterior extremity of the metatarsal bone sup-
porting the little toe; becoming fleshy, it crosses over
the anterior extremities of the other metatarsal bones.
Inserted, tendinous, into the anterior extremity of
the metatarsal bone of the great toe, and into the
internal sesamoid bone, adhering to the adductor
pollicis.
It contracts the foot, by approximating the toes.
Ranging with this order of muscles, we may also
observe a broad, strong ligament, passing from the
anterior sinuosity of the os calcis over the surface of
the os cuboides, and the tendon of the tibialis pos-
ticus, dividing into numerous tendinous slips, to be
inserted into the bones of the tarsus.
Having removed the muscles last described, we
expose the fourth and last order.
The tendon of the peroneus longus is seen passing
along a groove in the os cuboides, and crossing the
tarsal bones, to be inserted into the base of the meta-
tarsal bone of the great toe, and into the internal
cuneiform and second metatarsal bones.
Interossei Pedis Interni, are three in number,
situated in the sole of the foot. They arise, tendi-
nous and fleshy, from between the metatarsal bones
of the four small toes, and are
Inserted, tendinous, into the inside of the base of
the first phalanx of each of the three small toes.
Used to move the three smaller toes inwards
towards the great toe.
Interossei Pedis Extern i, are four in number,
larger than the internal interossei, and situated on the
back of the foot; they are bicipites, or arise by two
slips.
Arise, tendinous and fleshy, between the metatarsal
bones of all the toes.
Inserted, the first, abductor indicis pedis, into the
inside of the base of the first phalanx of the fore-toe;
GLIDE TO ANATOMY. 93
the second, adductor indicis pedis, into the outside of
the same toe; — the third, adductor medii digiti pedis,
into the outside of the middle toe; — the fourth, adduc-
tor tertii digiti pedis, into the outside of the third toe.
Used to separate the toes.
CHAPTER VI.
DISSECTION OF THE UPPER PART
OF THE BODY.
SECTION I.
THE EXTERNAL PARTS OF THE HEAD.
The integuments of the head are thick, and covered
with hair, having beneath the cutis a condensed cel-
lular substance, which is closely connected with the
epicranium, or expanded tendon of the occipito-fronta-
lis, and renders the dissection of that muscle difficult.
The only muscle, which properly belongs to the
hairy scalp, is a single broad digastric muscle, viz:
Occipito-frontalis. It arises fleshy and tendinous,
from the transverse ridge of the occipital bone, as far
forward as the mastoid process; forming a broad thin
tendon, which covers the whole upper part of the
cranium; it is
Inserted, fleshy, on each side, into the orbicularis
palpebrarum, the skin of the eye-brows, and the
internal angular process of the os frontis and os nasi.
The tendon of this muscle adhering firmly to the
skin, and but loosely to the pericranium, enables it to
94 LONDON DISSECTOR, OR
raise the eye-brows, and corrugate the skin of the
forehead.
The muscles of the external ear are not always so
distinct as to admit of a clear demonstration.
(1) Attollens Aurem, or the Superior auris —
Jlrises from the tendon of the occipito-frontalis, and
from the aponeurosis of the temporal muscle.
Inserted into the upper part of the root of the car-
tilage of the ear, opposite to the antihelix.
Used to draw the ear upwards.
(2.) Anterior Auris — Arises, thin and membra-
nous, from the posterior part of the zygomatic process
of the temporal bone.
Inserted into a small eminence on the back of the
helix, opposite to the concha.
Use: To draw the eminence a little forwards and
upwards.
(3.) The Retrahentes Auris, or Posterior auris —
Jlrises by two or three distinct slips, from the external
and posterior part of the mastoid process, immedi-
ately above the insertion of the sterno-cleido mastoi-
deus. t
Inserted into that back part of the ear which is
opposite to the septum, dividing the scapha and
concha.
Use: To draw the ear back, and stretch the concha.
The proper muscles of the ear are next to be
described; but the student must not expect to meet
with them distinctly marked in every subject; in
general they are very confused and indistinct.
(1.) Helicis Major — Jlrises from the upper and
acute part of the helix, anteriorly.
Inserted into its cartilage, a little above the tragus.
Use: To depress the part from which it arises.
(2.) Helicis Minor — Jlrises from the inferior and
anterior part of the helix.
GUIDE TO ANATOMY. 95
Inserted into the crus of the helix, near the fissure
in the cartilage opposite to the concha.
Use: To contract the fissure.
(3.) Tragicus — Arises from the middle and outer
part of the concha, at the root of the tragus, along
which it runs.
Inserted into the point of the tragus.
Use: To pull the point of the tragus a little
forwards.
(4.) Antitragicus — Arises from the internal part
of the cartilage that supports the antitragus; and,
running upwards, is
Inserted into the tip of the antitragus as far as the
inferior part of the antihelix.
Use: To turn the tip of the antitragus a little out-
wards, and depress the extremity of the antihelix
towards it.
(5.) Transversus Auris — Arises from the promi-
nent part of the concha on the dorsum of the ear.
Inserted opposite to the outer side of the antihelix.
Use: It draws the parts to which it is connected
towards each other, and stretches the scapha and
Concha.
The muscles of the internal ear are situated within
the temporal bone itself; they are very small, and
can be seen only when the internal parts of the organ
of hearing are prepared; but their description is
necessary to complete the history of the muscles.
(1.) Laxator Tympaxi — Arises, by a small origin,
from the spinous process of the sphenoid bone, and
the side of the Eustachian tube. It runs backwards,
and a little upwards, along with the nerve called
Chorda Tympani, in a fissure of the glenoid or articu-
lar cavity of the os temporis.
Inserted into the long process of the malleus.
Use: To draw the malleus obliquely forwards to-
wards its origin, and consequently the membrana
96 LONDON DISSECTOR, OR
tympani by which that membrane is made less con-
cave, or is relaxed.
(2 .) Tensor Tympani — Arises, by a small fleshy
beginning, from the cartilaginous extremity of the
Eustachian tube, just where it begins to be covered
by the pars petrosa and spinous process of the sphe-
noid bone, and runs along the bony half-canal of the
typanum, where it is invested by a membranous
vagina.
Inserted into the neck of the malleus, above the
small process, and even as far as the handle.
Use: To draw the malleus and membrana tympani
towards the pars petrosa, and thus render the mem-
brane more concave and tense.
A third, but much less distinct muscle, has been
described, under the name of External or Superior
Muscle of the malleus.
It arises from the internal, superior, and posterior
part of the meatus externus, to be fixed by a small
tendon to the neck of the malleus.
3. Stapedius is a short and thick muscle. It
arises from, and lies concealed within, the small bony
pyramid at the bottom of the tympanum; the cavity
which it fills is near the bony canal for the portio
dura of the auditory nerve. It terminates in a small
tendon, which passing out of the cavity through the
small hole in the apex of the pyramid, runs forwards,
and is
Inserted into the neck of the stapes, on the sides of
the longest and most crooked leg of that bone.
Use: To draw the stapes obliquely upwards to-
wards the pyramid, by which the posterior part of
its base is moved inwards, and the anterior part
outwards.
GUIDE TO ANATOMY 97
SECTION II.
OF THE CONTEXTS OF THE CRANIUM, OR THE BRAIN
AND ITS MEMBRANES.
A transverse incision, extending from ear to ear
over the crown of the head, being made through the
tendon of the occipito-frontalis, the two flaps mav,
with facility, be inverted on the face and neck.
Remove the superior part of the cranium by a saw
directed anteriorly through the frontal bone above the
orbitar process, and posteriorly as low as the trans-
verse ridge of the occipital bone.
When the superior part of the cranium, commonly
railed the Calvarium, or skull-cap, has been torn off,
for which considerable force is requisite, you expose
the Dura Mater, a firm, compact, and whitish mem-
brane, somewhat shining, rough on its outer surface,
from the rupture of vessels which connected it to the
cranium, and covered with bloody spots in conse-
quence of the blood effused from these ruptured ori-
fices. It is described as being separable into many
laminae; two, however, with facility, may be demon-
strated; and it is said that these two laminae, by
separating and re-uniting, form the triangular cavities,
named Sinuses, which are, in fact, large veins. This
division of layers can hardly be admitted as correct
in the recent state of the membrane.
The Superior Longitudinal Sinus lies in a
groove formed by the two parietal bones; it extends
along the sagittal suture from the crista galli of the
ethmoid bone to the middle of the os occipitis, where
it bifurcates into the two lateral sinuses; in its passage
backwards, its size is increased. When slit open, its
triangular form is evident; it is lined by a smooth
membrane, and in it may be remarked the numerous
9
98 LONDON DISSECTOR, OR
openings of the veins of the pia mater, the frena, or
slips of fibres crossing from side to side, the glandulae
Pacchioni interns et externae, which are little bodies
like millet-seed, seen on the outer and inner surface of
the sinus.
The arteries of the dura mater are divided into the
anterior, middle, and posterior.
1. Arteria Meningea Media (called also the
Spinalis or Spheno-spinalis) the great middle artery, is
a branch of the internal maxillary; it passes through
the spinous hole of the sphenoid bone, and is seen rising
from the anterior inferior angle of the parietal bone
(in a groove of which it lies,) and spreading its nume-
rous branches over the dura mater.
The anterior and posterior arteries are small.
2. A. Meningea Anterior is sent off from theex-
lernal carotid, and enters the cranium by the foramen
lacerum orbitale superius.
3. A. Meningea Posterior is given off by the
vertebral artery; the dura mater also receives small
twigs from the occipital, pharyngeal arteries, &c.
The nerves of the dura mater are said to come from
the fifth pair; if they exist at all, they are small, and
seldom demonstrated.
OF THE SEPTA OF THE BRAIN, OR PROCESSES OF
THE DURA MATER.*
1. The Falx (septum sagittale, verticale, mediasti-
num cerebri or falciform process) is a long, broad fold,
or duplicature of the inner lamina of the dura mater,
dividing the cerebrum into two hemispheres, extend-
ing from the crista galliof the ethmoid bone, along the
* To demonstrate these, the dura mater should be divided in the line
of the division of the cranium: its internal surface will be found smooth,
glistening, and free from adhesion, except in the course of the longitudi-
nal sinus, into which veins pass from the pia mater.
GUIDE TO ANATOMY. 99
middle of the os frontis and point of junction of the two
parietal bones,to the crucial ridge of the occipital bone,
where it terminates in the middle of the next septum.
2. The Tentorium Cerebelli, or transverse sep-
tum. This separates the cerebrum from the cerebel-
lum, and is formed by the inner lamina of the dura ma-
ter, reflected oft" from the os occipitis along the groove
of the lateral sinuses, and the edge or angle of the tem-
poral bones. It is frequently called Tentorium Cere-
bello Super Extensum. Its position is horizontal.
There are some other folds of the dura mater, not
visible in this stage of the dissection,, viz:
3. The falx of the cerebellum, or small occipital sep-
tum, which will be seen when the cerebrum is removed.
It extends from the middle of the tentorium along the
middle spine of the os occipitis to the foramen magnum,
dividing the cerebellum into two parts.
4. The sphenoidal folds, two small folds of the dura
mater, one on each side of the sella turcica, stretching
from the posterior to the anterior clinoid processes.
The dura mater also, in many parts of the brain,
separates its laminae to form sinuses; the principal of
these will be noticed in the course of the dissection.
Detach the falx from the crista galli, and turn it back-
wards; observe in its lower edge the Inferior Lon-
gitudinal Sinus, which enters a sinus in the Tento-
rium, termed Torcular Hierophili, or straight sinus.
This will fully expose the convolutions of the brain,
which are closely invested by the pia mater.
The next membrane which we meet is the Tunica
Arachnoides. It is a transparent membrane, cover-
ing uniformly the surface of the pia mater, without
passing into the interstices of its duplicatures. It is
attached to it, is extremely thin, without vessels, de-
monstrated with difficulty on the upper suiface of the
brain by the blow-pipe (which raises it into cells,) but
on the base of the brain it can be distinctly seen.
100 LONDON DISSECTOR, OR
Beneath the last membrane is found the Pia Mater,
or tunica vasculosa, a very vascular membrane, trans-
parent in the interstices of its vessels, investing the sub-
stance of the brain, descending betwixt all its convo-
lutions, and lining its different cavities; but, where it
lines the ventricles it is fine, delicate, and less vascu-
lar, than on the surface, and betwixt the convolutions
of the brain: It is connected to the dura mater by its
veins passing into the longitudinal sinus.
The brain is divided into three parts: The cere-
brum; the cerebellum; and the medulla oblongata.
The Cerebrum consists of two distinct, substances:
1 . The cineritious or cortical substance forming the
outer part.
2. The white or medullary substance forming the
inner part.
The brain is divided by the falx into two hemis-
pheres, and by the pia mater into numerous convolutions.
Each hemisphere is divided into three lobes.
The Anterior Lobes rest on that part of the cra-
nium which forms the two orbits, and is called the
anterior fossae of the basis of the cranium.
The Middle Lobes are situated before and above
the medulla oblongata, and rest on the middle fossae of
the basis cranii, which are formed by the sphenoid and
temporal bones.
The Posterior Lobes are supported by the ten-
torium.
The anterior and middle lobes are parted by a deep
narrow sulcus, which ascends obliquely backwards
from the temporal ala of the os sphenoides to near the
middle of the os parietale; it is termed Fissura Cere-
bri, or Fissura Magna Silvii.
By gently separating with the fingers the two hemis-
pheres of the brain,* we see passing betwixt them a
* Between the hemispheres and on the surface of the corpus callosum,
we observe, if the arteries are injected, the arteria: callosa?, which are
the continuation of the trunks of the anterior cerebri.
GUIDE TO ANATOMY. 101
longitudinal white convex body, the Corpus Callo-
>im; it lies under the falx, incurvates downwards at
both its extremities, and is continued anteriorly into the
medullary substance betwixt the corpora striata, pos-
teriorly into the fornix and inferior cornu of the lateral
ventricle on each side. From its connecting the two
hemispheres it is called the Commissura Magna. On
the surface of the corpus callosum is seen the Raphe,
formed by two longitudinal medullary lines united by
transverse fibres.
When the brain is cut horizontally on a level with
the corpus callosum, an appearance is produced,
termed the Medullary arch, or Centrum Ovale.
When only one of the hemispheres is sliced off to this
level, the appearance presented by the medullary
substance is called the centrum ovale parvum of Vicq
d'Azyr.
Under this arch are the two lateral ventricles.* If
one of these be cautiously perforated on the side of
the corpus callosum, and gently inflated by a blow-
pipe, its extent may be seen; but, if much force be
used, the air will pass into the other ventricle.
The two ventricles are separated by a medullary
partition, which descends from the inferior surface of
the corpus callosum to the fornix, and is called the
Septum Lucidum; it consists of two laminae, with a
narrow cavity between. To see this septum, one of
the ventricles must be laid open, and the septum pulled
gently to the other side.
The Lateral Ventricles are two in number, the
right and the left, lined with a fine membrane, narrow,
consisting of a body, and three prolongations or cor-
nua.
* To show the lateral ventricles, the corpus callosum should be c-.:t
away close to the septum lucidum; and Uien, the ventricle of that body,
and the thickness and breadth of the septum itself, will bj more clearly
seen.
9*
102 LONDON DISSECTOR, OR
1 . The body is formed betwixt the corpus callosum,
the medulla of the brain, the convexity of the corpus
striatum, and the thalamus nervi optici.
2. The anterior cornu or horn is formed betwixt
the more acute convexity of the corpus striatum, and
the anterior part of the corpus callosum.
3. The posterior cornu (called also the digital
cavity) may be traced stretching backwards and down-
wards into the posterior lobe of the brain.
4. The inferior or descending cornu cannot be
traced in this stage of the dissection; it seems like the
continued cavity of the ventricle, takes a curve back-
wards and outwards, and then, turning forwards,
descends into the middle lobe of the brain.
The lateral ventricles communicate with each other,
and with the third ventricle, by an opening under the
fore part of the arch of the fornix, called the foramen
commune anterius*
In the lateral ventricles we meet with
The Fornix, a medullary body, flat, and of a tri-
angular shape; which divides the two lateral and the
third ventricles. It is exposed on tearing away the
septum lucidum; its lower surface is towards the third
ventricle; its lateral margins are in the lateral ventri-
cles; on its upper surface it supports the septum luci-
dum, and under its most anterior part is the foramen
Momoianum: — One of the angles of this body is for-
ward, and the other two towards the back part; it
rests chiefly on the thalami nervorum opticorum, but
* It has been doubted whether or not this be an opening; the choroid
plexus passes through it, and seems to unite the surfaces; it is absurdly
named the Foramen Monroianum, from a mistaken notion that Dr. Monro
discovered it, and may be seen by gently turning- the anterior crus of the
fornix to one side; it is a space betwixt the most anterior part of the con-
vexity of the thalami nervorum opticorum, and the anterior cms of the
fornix.
This foramen may always be easily found by following the course of
the plexus choroides, as it passes forwards in the ventricle. It is a slit,
rather than a round hole, in the natural state.
GUIDE TO ANATOMY. 103
is separated from them by a vascular membrane called
the velum.
The extremities of the body of the fornix are named
its Crura.
1 . The crus anterius is double, bends downwards
before the anterior commissure of the brain, with
which it is connected, and may be traced into the cor-
pora albicantia.
2. The two crura posteriora, coalescing with the
back part of the corpus callosum, pass, on each side,
into the inferior cornu of the lateral ventricle, and
terminate in a pointed form on the hippocampus major.
Divide the body of the fornix, invert it, by turning
the anterior crus forwards, and the posterior crura
backwards; on the under surface of the latter is an
appearance of transverse lines, named Corpus Psal-
loides, psalterium, or lyra.
The inversion of the fornix exposes
The Plexus Choroides. — This is a continuation
of the pia mater, a spongy mass, consisting of folds of
tortuous vessels, partly covering the thalami nervorum
opticorum, and continued into the inferior cornu of
the lateral ventricles. The plexus of each side is
connected to its fellow by the velum interpositum, a
membrane which passes under the fornix, and lies on
the third ventricle and corpora quadrigemina.
From this plexus the blood is received by the Vena
Galeni, situated in the middle of the velum which
consists of two parallel branches; these run backwards,
unite, and enter the fourth sinus of the dura mater,
called Torcular Hierophili.
This plexus should now be detached at its fore part,
and turned back: it will remain as a guide to the knife
in tracing the inferior cornu of the lateral ventricle.
We now see
The Corpora Striata, two smooth cineritious
convexities, in the fore part of the lateral ventricle,
104 LONDON DISSECTOR, OR
broad, and rounded anteriorly, becoming narrow, and
diverging as they pass backwards, consisting of
medullary and cortical substance disposed in striae.
The Thalami Nervorum Opticorum, two large
oval, whitish eminences, placed by the side of each
other between the diverging extremities or crura of
the corpora striata; towards their fore part is a peculiar
eminence or convexity, called the Anterior Tubercle
or Monticulus; they are elongated downwards, to form
the optic nerves.
The Taenia Semicircularis, is a white medullary
line, running in the angle betwixt the corpus striatum
and thalamus nervi optici of each side.
The Commissura Anterior Cerebri, is a short*-
cylindrical medullary cord, stretched transversely
between the fore and lower part of the corpora striata,
immediately under the anterior crura of the fornix.
Just above the commissura anterior, and before
the thalami, is the Vulva, or foramen commune ante-
rius, a small slit or indentation, formed by the anterior
crus of the fornix, bifurcating, and inserting itself, on
each side, between the corpus striatum and thalamus
nervi optici. This slit is the space by which the
three ventricles communicate.
The Commissura Mollis is an exceedingly soft,
broad, cineritious junction betwixt the convex surfaces
of the thalami nervorum opticorum.
On separating the optic thalami, we discover the
Third Ventricle. This is a longitudinal sulcus, or
slit, situated betwixt the thalami nervorum opticorum,
and betwixt the crura cerebri. Above, it is covered
by the fornix and velum interpositum; at its upper and
fore part, it communicates with the two lateral ven-
tricles; below the commissura anterior, it opens into
the infundibulum. This opening is termed iter ad
infundibulum. Backwards, it is continued by a canal
which passes under the tubercula quadrigemina into
GUIDE TO ANATOMY. 105
the fourth ventricle. This passage is named iter ad
quartum ventriculum, aquaeductus Sylvii, or canalis
medius.
The Anus, or foramen commune posterius, is situ-
ated behind the commissure of the optic thalami, and
before the corpora quadrigemina. It is closed up by
the velum interpositum, and, when that is removed,
leads into the back part of the third ventricle.
The Pineal Gland, a small, soft, greyish, and
conical body, of the size of a pea, is seated above the
tubercula quadrigemina, and behind the thalami,
to which it is connected by two white pedunculi, or
foot-stalks; its base is turned forwards, and the apex
backwards; it is covered by the plexus choroides and
posterior crura of the fornix. It contains an earthy
matter, either in its own substance, or that of the
pedunculi, resembling sand, and, when viewed by a
magnifier, assuming a granulated and clear light
yellow appearance. It was named by Soemmerring,
who first discovered that it belongs to the healthy
structure of the brain, the Acervulus Glandul.e
PlNEALIS
The Commissura Posterior is a transverse cord
at the back part of the third ventricle, before the tu-
bercula quadrigemina, and above the iter ad quartum
ventriculum.
Tubercula QuADRiGE>iiNA,four small white bodies,
adhering together, lying under the pineal gland, behind
the third ventricle, and above the fourth. The upper-
most two are named Nates, and the other two Testes.
From the under part of the testes, there projects
backwards, connecting itself-with the crura cerebelli,
a thin medullary lamina, which is the valvula V ieus-
senii, called also processus a cerebello ad testes, velum
interjectum, valvula major.
The inferior cornu of the lateral \entricle, which
descends into the middle lobe of the brain, may now be
106 LONDON DISSECTOR, OR
traced, by following the tract of the choroid plexus;*
in it is seen
The Hippocampus Major, or Cornu Ammonis. At
its commencement it is narrow, but it becomes a broad
medullary projection of the floor of the ventricle, and
its extremity, which is called Pes Hippocampi, is
curved inwards. The thin edge on its inside, which
follows the whole of its circuit, is named the Corpus
Fimbriatum, or Taenia Hippocampi. The posterior
crus of the fornix runs along its inner and anterior part,
in the form of a thin floating edge.
In the posterior cornu of the lateral ventricle, which
passes into the posterior lobe of the brain, there is a
similar medullary projection, but smaller, the Hippo-
campus Minor.
In the anterior part of the third ventricle, below the
iter ad infundibulum, are seen the Corpora Albi-
cantia Willisii (corpora mamillaria or subrotunda,)
two medullary eminences of the size of peas; the
remainder of these bodies is seen on the outer surface
of the base of the brain.
This completes the demonstration of the cerebrum.
The whole of the posterior lobes, and the lateral part
of the middle lobes, may be removed. This exposes
to your view,
The Tentorium, and the Falx Cererelli. At
this point you should trace the bifurcation of the lon-
gitudinal sinus into the two lateral sinuses. The lateral
sinuses are formed by the splitting of the laminae of
the tentorium; hence they follow the course of that
membrane, run along their grooves in the occipital
bone, and dip downwards and forwards through the
foramen lacerum in basi cranii, to terminate in the
internal jugular veins.
* Or it may be exhibited by cuttingaway successive slices of the side
of the brain, until the ventricle is exposed.
GUIDE TO ANATOMY. 107
The Torcular Hierophili, or fourth sinus, runs
along the middle of the tentorium, and joins the ex-
tremity of the longitudinal sinus at the point where it
bifurcates.
The great notch of the tentorium is a circular open-
ing left on the anterior part of the tentorium, allow-
ing a junction between the cerebrum and cerebellum.
Proceed next to the examination of the cerebellum;
and, in order to accomplish this demonstration, it will
be convenient to remove the posterior part of the os
occipitis.
Cerebellum. — This part of the brain, divided into
two lobes by the falx cerebelli, or septum occipitale,
is covered by a vascular membrane; consists of me-
dullary and cineritious substance; but instead of convo-
lutions, has numerous deep sulci, into which the pia
mater dips, and forms thin flat strata.
Remark the following processes:
1 . Appendix, vel processus vermiformis superior,
situated under the pia mater, on the anterior and supe-
rior part of the cerebellum.
2. Appendix, or processus vermiformis posterior, will
be found situated between the two lobes on the under
surface of the cerebellum, and immediately behind the
medulla oblongata.
On separating the two lobes behind, and making a
deep incision, we discover
The Fourth Ventricle. — The sides of this ven-
tricle are formed by the cerebellum, the anterior part
by the medulla oblongata, the upper and back part by
the valvula cerebri; it is lined by a thin vascular mem-
brane,and has on its fore part a groove or fissure,which,
terminating in a sharp point, is named Calamus Scrip-
torius. On each side of this groove are seen several
medullary lines, which are the origin of the portio mol-
lis of the seventh pair of nerves. The iter a tertio ad
108 LONDON DISSECTOR, OR
quartum ventriculum enters the upper part of the fourth
ventricle. The valvula cerebri hangs over it.
On cutting the cerebellum perpendicularly, there is
formed, from the intermixture of cineritious and me-
dullary matter, a tree-like appearance, named Arbor
Vit^e, of which the trunk is termed the peduncle of
the cerebellum, and is continued to the back part of
the medulla oblongata. This concludes the demon-
stration of the cerebellum.
To demonstrate the medulla oblongata and nerves,
either the brain must be removed from the cranium,
or it may be gradually inverted in the progress of the
demonstration; — and this is the better method. The
inversion must be begun at the fore-part, by raising the
anterior lobes of the cerebrum. Thus you will see,
1 . The First Pair of Nerves, the Olfactory,
called also Processus Mammillares. They .arise from
the outside of the corpora striata, between the anterior
and middle lobe of the brain; run under the anterior
lobes; being lodged on two superficial grooves, and
lying between the pia and dura mater; expand into a
small oval ganglion, from which several small filaments
descend through the cribriform plate of the ethmoid
bone, to ramify on the membrane lining the nose.
2. The Second Pair, the Optic, arise from the
posterior part of the optic thalami, and also from the
tubercula quadrigemina; they make a circle round the
crura cerebri called the Tractus Opticus. The two
nerves approach gradually, and unite, just before the
pituitary gland, on the fore part of the sella Turcica.
They then diverge, and each nerve passes out at the
foramen opticum of the sphenoid bone, to form the
retina of the eye.
On each side of these nerves are seen the Carotid
Arteries. Each artery emerges from the cavernous
sinus by the side of the anterior clinoid process: sends
GUIDE TO ANATOMY. 109
a branch forwards, which, uniting with a similar branch
of the other carotid, forms the anterior part of the Cir-
culus Arteriosus Willisii; while other branches,
passing backwards, and uniting with branches of the
basilar artery, complete the posterior part of the arte-
rial circle.
A fold of dura mater passes from the anterior to the
posterior clinoid process of each side. This fold is
double, and forms by its duplicative the Cavernous
Sinus.
On dividing the optic nerves, and inverting them,
we see the infundibulum, a funnel of cineritious sub-
stance, leading from the inferior and anterior extremity
of the third ventricle to the pituitary gland; it is gene-
erally imperforate before it reaches the gland.
The Pituitary Gland, a reddish body, somewhat
globular, consisting of two lobes, is situated in the
sella Turcica of the sphenoid bone, partly covered by
a fold of dura mater, and attached to the infundibulum.
The circular sinus is situated at this point
On detaching the cerebrum from the back part
of the sella Turcica, the tunica arachnoides is very
evident.
3. The Third Pair of Nerves, Motores Ocu-
lorum, arise from the crura cerebri*, pass outwards
and forwards on the outer side of the posterior clinoid
process into the cavernous sinus, and run through the
foramen lacerum orbitale superius to the muscles of
the eye.
Between these two nerves are seen the two ver-
tebral arteries, ascending and uniting, to form the
basilary artery.
* The two crura pass obliquely backwards and inwards, so as to con-
verge and meet in front of the tuber annulare; it is from the hollow
formed by their convergence, and named by Vicq d'Azyr, fosse des
nerfs occulo-musailaires , that the third pair arise.
10
110 LONDON DISSECTOR, OR
4. The Fourth Pair, Trochleares or Pathet-
ici, are very dender, and situated immediately under
the edge of the tentorium. This nerve arises from
the valvula cerebri, comes out from betwixt the cere-
brum and cerebellum, passes by the side of the pons
Varolii, and, passing through the cavernous sinus,
continues its course through the foramen lacerum
orbitale superius, to supply the obliquus superior
muscle of the eye.
5. The Fifth Pair, Trigemini, are much larger
than the fourth, and are situated more outwards and
backwards. Each of these nerves arises, by a num-
ber of filaments, from the anterior and lowest part of
the crus cerebelli, where the crus unites with the
pons Varolii; — it passes forwards, enters the cavern-
ous sinus, where it untwists itself, and forms a flat
irregular ganglion, the Ganglion Gasserianum, and
then divides into three great branches.
(1.) Ramus Ocularis. — The ophthalmic nerve of
Willis passes through the foramen lacerum orbitale
superius to the appendages of the eye.
(2.) Ramus Maxillaris Superior passes through
the foramen rotundum to the upper jaw and face.
(3.) Ramus Maxillaris Inferior passes through
the foramen ovale to the lower jaw and tongue.
6. The Sixth Pair, Motores Oculorum Ex-
terni, or abductores vel abducentes. — This nerve is
small, but not so small as the fourth pair; it is seen
arising betwixt the pons Varolii and corpora pyrami-
dalia: it enters the cavernous sinus, — it there runs by
the side of the carotid artery, and passes through the
foramen lacerum orbitale superius to the rectus exter-
nus oculi.
While in the cavernous sinus, it gives off the small
twig, which, uniting with filaments from the second
branch of the fifth pair, forms the beginning of the
GUIDE TO ANATOMY. Ill
intercostal nerve, and passes out of the cranium
through the foramen caroticum with the carotid artery.
7. The Seventh Pair, Nervi Auditorii, con-
sists of two portions.
(1.) The Portio Dura, or the fascial nerve, arises
from the cms cerebelli, and comes out from the fossa
or groove betwixt the pons Varolii, corpora olivaria,
and crura cerebelli.
(2.) The Portio Mollis, or more properly the audi-
tory nerve, arises from the inner surface of the fourth
ventricle; it has a groove on its surface for receiving
the portio dura; — accompanied by an artery, they
enter the meatus auditorius internus, where the portio
mollis is distributed to the parts of the internal ear,
while the portio dura runs through the aqueduct of
Fallopius, and comes out at the stylo-mastoid foramen
below the ear, to form the principal nerve of the face.
8. The Eighth Pair, Par Vagum, arises by
numerous filaments from the sides of the corpora
olivaria and medulla oblongata. Two distinct fasci-
culi are formed, the uppermost called nervus glosso-
pharyngeus, the other the proper par vagum; — they
unite, run towards the foramen lacerum in basi cranii.
pierce the dura mater, and pass out through the ante-
rior part of that hole, having been first joined by the
Nervus Accessorius ad Par Vagum, or spinal
accessory, which runs up from the medulla spinalis
through the great occipital foramen.
The great Lateral Sinus passes out by the back-
part of the same foramen, to form the internal jugular
vein; it is separated from the nerve by a slip of
cartilage.
9. The Ninth Pair, Linguales, Linguales Medii,
Hypoglossi. — This nerve arises from the furrow
betwixt the corpora olivaria and pyramidalia, by
several filaments which often pierce the dura mater
separately. It passes through the anterior condyloid
112 LONDON DISSECTOR, OR
hole of the occipital bone, to supply the muscles of
the tongue.
Immediately after leaving the cranium, the eighth
and ninth pair, and the ganglion of the intercostal,
are connected together.
10. The Tenth Pair,* Suboccipitales, arise, on
each side, by two bundles, from the extremity of the
medulla oblongata, and upper part of the spinal mar-
row, pass through the dura mater by the same foramen
which gives entrance to the vertebral artery, and run
through the foramen magnum occipitale to the muscles
at the base of the cranium.
The corpora albicantia Willisii, are again seen,
two white bodies, on the base of the brain, behind
the infundibulum, and above the pons Varolii.
The Medulla Oblongata remains to be demon-
strated. It should be removed from the bone, and
examined in an inverted position. On its under surface
are seen the two vertebral arteries, ascending from
the foramen magnum, and uniting, to form one trunk,
the basilar artery.
On removing the pia mater, the whole surface
appears medullary; but an incision shows it to be
intermixed with the cineritious substance.
The Crura or Pedunculi Cerebri are two con-
siderable medullary fasciculi, proceeding from the
centre of the medulla of the brain, more immediately
from the corpora striata; they unite at an acute angle,
and are united to the pons Varolii.f
The Crura or Pedunculi Cerebelli are very
large, and pass from the medullary part of the cere-
bellum which forms the arbor vitae to the pons Varolii.
* These are now perhaps as frequently described as the first pair of
cervical nerves.
t On making a section of the crura cerebri, near to their union with
the pons Varolii, a portion of a dark-brown colour, surrounded with
white medullary substance, is seen, termed Locus Niger Cruruin
Cerebri.
GUIDE TO ANATOMY.
113
The Pons Varolii, Tuber Annulare, or Nodus
Cerebri, is a medullary protuberance, formed by the
union of the crura cerebri and cerebelli, over which
it is stretched like a bridge; on its surface is a raphe,
or transverse fibres passing into a middle longitudinal
narrow depression.
Below the pons Varolii, and separated from it by a
sulcus, are seen four eminences:
1. The two external are named Corpora Oliva-
RIA.
2. The two internal are named Corpora Pyra-
midalia, and, by separating these two bodies, medul-
lary cords, passing transversely, appear, the nervi
intercerebrales.
Small cords also project from the back part of the
corpora olivaria, which have received the name of
Corpora Restiforniia.
The point of union betwixt the corpora pyramidalia
and pons Varolii, is sometimes called foramen caecum.
The medulla oblongata now contracts itself, and
passing through the foramen magnum occipitale,
assumes the name of
Medulla Spinalis, or the Spinal Marrow. This
part of the nervous or sensorial system must be here
described, although its dissection cannot be performed
till all the muscles of the back are removed, so that
the posterior part of the spinal canal mav be sawed
off.
The spinal canal is lined by a strong ligamentous
sheath, and the dura mater is continued down upon this
sheath in the form of a funnel.
The spinal marrow consists externally of medullary
substance, internally of cineritious. It runs down to
the first lumbar vertebra, where it terminates by
numerous filaments, which form the cauda equina. It
is closely embraced by the pia mater, while the tunica
arachnoides adheres to that membrane very loosely.
10*
1 1 4 LONDON DISSECTOR, &C.
During the whole of its passage, there is on each side
a membranous connection betwixt the pia and dura
mater, by distinct slips, irregular and pointed, which
connection is named Ligamentum Denticulatum.
The arteries of the medulla may be seen running down
on its anterior and posterior surfaces; they are branches
of the vertebral artery.
The spinal accessory nerve is seen arising by small
twigs from the posterior bundles of the fourth, fifth,
sixth, and seventh cervical nerves; it then ascends
along the spinal canal, enters the foramen, and passes
forwards, to accompany the par vagum.
The spinal marrow sends off twenty-nine pair of
spinal nerves, which pass through the foramina formed
betwixt the bodies of the vertebrae. They consist of
seven cervical, twelve dorsal, five lumbar, and five
sacral pairs of nerves. Each of these nerves arises
in two fasciculi, one from the fore part, the other from
the back part of the spinal marrow; these fasciculi
penetrate the dura mater separately; the posterior
bundle forms a ganglion, and afterwards unites with
the anterior fasciculus, to form the nerve.
CHAPTER VIT.
DISSECTION OF THE ANTERIOR
PART OF THE NECK.
The utility of this dissection must be evident, when
you consider how many important parts are contained
in the fore part of the neck. The tube which conveys
air to the lungs, the vessels which are sent from the
heart to the brain, and the nerves which are destined
to supply the thoracic and abdominal viscera, are here
situated, and all these parts lie imbedded in cellular
substance; hence the dissection is intricate,and requires
the utmost care in its performance.
The muscles of the anterior part of the neck, are
sixteen in number on each side. They may be divided
into muscles situated superficially, muscles at the upper
part of the neck, and those situated at the lower part.
The superficial muscles are two: to display them,
make an incision from the chin to the sternum, another
along the clavicle, and a third along the edge of the
inferior maxillary bone; dissect up the flap and you will
expose immediately under the integuments, and adher-
ing to them,
1. The Musculus Cutaxeus, vulgo, Platysma
myoides, or Latissimus Colli. — It arises, by slender
separate fleshy fibres, from the cellular substance,
covering the upper part of the deltoid and pectoral
muscles. These fibres form a thin broad muscle,
which runs obliquely upwards, and is
Inserted into the skin and muscles covering the lower
jaw and cheek.
116 LONDON DISSECTOR, OR
Use: To draw the skin of the cheek downwards,
and, when the mouth is shut, to draw the skin under
the lower jaw upwards: others say that it assists the
respiration and circulation.
Remove the platysma myoides from its origin, and
invert it over the face. Immediately beneath it is seen
the external jugular vein, which is formed of branches
from the temple, side of the face, and throat. It crosses
obliquely over the sterno-mastoideus, passes behind
the outer edge of that muscle, and dives beneath the
clavicle, to enter the subclavian vein.
2. The Sterno-Cleido-Mastoideus — Jlrises, by
two distinct origins; the anterior, tendinous and fleshy,
and somewhat round, from the top of the sternum, near
its junction with the clavicle; the posterior or outer,
fleshy and flat, from the upper and anterior part of the
clavicle. These two origins soon unite, and form a
strong muscle, which ascends obliquely upwards and
outwards, to be
Inserted, tendinous, into the outside of the mastoid
process, and into the transverse ridge behind that pro-
cess.
Use: When one acts singly, it turns the head to one
side. When both act together, they bend the head
forwards.
The muscle should be detached from the sternum
and clavicle, and left suspended by its insertion. It is
pierced by several branches of the cervical nerves, and
about its middle, it is perforated by the Nervus Ac-
cessorius. These nerves ramify on the neighboring
muscles of the neck and shoulder. Between the pos-
terior edge of the sterno-cleido-mastoideus and the
fore part of the trapezius muscles, is seen a quantity
of loose fatty substance, intermixed with branches of
nerves. This fatty substance is watery and granu-
lated; it must not be removed roughly, lest important
GUIDE TO ANATOMY. 1 IT
nerves and vessels be injured; it is continued around
the vessels under the clavicle.
In the middle of the throat may be seen:
The Os Hyoides, or bone of the tongue, forming the
uppermost of the projections beneath the chin.
The Larynx, or upper part of the trachea, consist-
ing of five cartilages, of which two are evident exter-
nally, viz: the uppermost and largest the thyroid car-
tilage; and the inferior or cricoid cartilage. The two
arytenoid cartilages, and the epiglottis, lie behind this.
The Trachea, consisting of cartilaginous rings,
and extending into the thorax.
Behind the larynx is situated the pharynx. At the
part where the larynx terminates in the trachea, the
pharynx contracts itself, and forms the oesophagus, or
muscular tube, conveying the food to the stomach,
which descends behind the trachea, situated rather to
the left side of the cervical vertebrae.
These parts are covered by muscles, and on each
side of the trachea lie the great vessels and nerves.
The muscles at the lower part of the neck are
five.
3. The Sterxo-Hyoideus — Arises, thin and
fleshy, from the upper and inner part of the sternum,
clavicle, and first rib: — It forms a flat narrow muscle.
Inserted into the base of the os hyoides.
This pair of muscles is seen on removing the
platysma myoides, between the sterno-cleido mas-
toidei.
Use: To pull the os hyoides downwards.
4. The Omo-Hyoideus — Arises, broad, thin, and
fleshy, from the root of the coracoid process, and
semilunar notch of the scapula, ascends across the
neck, and forms a middle tendon, where it passes
below the sterno-cleido-mastoideus. Becoming fleshy
again, it runs up, and is
118 LONDON DISSECTOR, OR
Inserted into the base of the os hyoides, between its
cornu and the insertion of the sterno-hyoideus.
The lower part of this muscle is covered by the
trapezius; its middle by the sterno-cleido-mastoideus;
its anterior part is seen on removing the platysma
myoides; it crosses over the carotid artery, and internal
jugular vein.
Use: To assist in drawing down the os hyoides.
On dividing the sterno-hyoideus, observe under it,
5. The Sterno Thyroideus. — This muscle arises,
fleshy, from the inside of the sternum, and of the
extremity of the first rib; forms a flat muscle, and is
Inserted into the inferior edge of the thyroid car-
tilage.
Use: To draw the thyroid cartilage, and conse-
quently the larynx, downwards.
Under the sterno-thyroideus, we find situated the
Thyroid Gland, a large reddish mass, situated on
the superior rings of the trachea, below the cricoid
cartilage; in form somewhat like a crescent, with the
cornua turned upwards.
6. The Thyro-Hyoideus — Arises, fleshy, from
the upper surface of the oblique ridge in the ala of
the thyroid cartilage, and passes upwards, to be
Inserted into part of the base, and almost all the
cornu of the os hyoides. It is covered by the sterno-
hyoideus.
7. The Crico-Thyroideus — Arises, tendinous and
fleshy, from the side and fore part of the cricoid
cartilage, and runs obliquely upwards.
Inserted, by two fleshy portions, the first into the
lower part of the thyroid cartilage, and the second
into its inferior cornu.
It is found on the side of the larynx, and under the
sterno-thyroideus, and serves to pull forwards and
depress the thyroid, or to elevate and draw backwards
the cricoid cartilage.
GUIDE TO ANATOMY. Il9
The muscles at the upper part of the neck consist
of nine pair.
8. The Digastricus — Arises, from the fossa at the
root of the mastoid process of the temporal bone; its
fleshy belly terminates in a strong round tendon,
which runs downwards and forwards, passes through
the fleshy belly of the stylo-hyoideus, is fixed by
strong ligamentous and tendinous fibres to the os
hyoides, from which it receives an addition of fibres;
it then becomes again fleshy, and runs obliquely
upwards, to be
Inserted into a rough sinuosity on the lower jaw
behind the Chin.
Its posterior belly is covered by the sterno-cleido-
mastoideus; but its anterior lies immediately under
the skin and platysma myoides.
Use: To open the mouth, by pulling the lower jaw
downwards and backwards; and, when the jaws are
shut, to raise the larynx, and consequently the pharynx,
• in deglutition.
In the triangular space formed by the two bellies of
this muscle, and the base of the lower jaw, lies the
Submaxillary Gland. It rests upon a flat muscle,
the mylo-hyoideus, which is seen between the two
bellies of the digastricus; the gland is surrounded by
little absorbent glands.
9. The Stylo-Hyoideus — Arises, tendinous, from
the middle and inferior part of the styloid process of
the temporal bone; its fleshy belly is generally perfo-
rated by the digastricus.
Inserted, tendinous, into the os hyoides at the junc-
ture of its base and cornu.
The origin of this muscle is situated more inwards
than the last, and nearer the base of the cranium; it is
the most superficial of three muscles which arise from
the styloid process; sometimes it is accompanied by
120 LONDON DISSECTOR, OR
another small muscle, having the same origin and
insertion, the stylo-hyoideus alter.
Use: To pull the os hyoides to one side, and a little
upwards.
10. The Stylo-Glossus — Arises, tendinous and
fleshy, from the styloid process, and from a ligament
that connects that process to the angle of the lower
jaw. It descends, and becomes broader, but less
thick.
Inserted into the root of the tongue, runs along its
side, and is insensibly lost near its tip.
Use: To move the tongue laterally and backwards.
1 1 . The Stylo-Pharyngeus — Arises, fleshy, from
the root and inner part of the styloid process.
Inserted into the side of the pharynx and back part
of the thyroid cartilage.
It is situated deeper, and behind the stylo-glossus,
and serves to dilate and raise the pharynx and thyroid
cartilage upwards.
On removing the submaxillary glands, and detaching
the digastric muscle from the os hyoides and chin, we
expose the next muscle.
1 2. The Mylo-Hyoideus — Arises, fleshy, from all
the inside of the lower jaw, between the last dens
molaris and the middle of the chin; the fibres form a
flat muscle, converge, and are
Inserted into the lower edge of the base of the os
hyoides; it unites with its fellow in a middle tendi-
nous line which extends from the os hyoides to the
chin; its posterior part is lined by the internal mem-
brane of the mouth; it lies under the digastricus, but
is seen betwixt its bellies.
Use: To pull the os hyoides forwards, upwards, and
to either side.
The submaxillary gland sends off a duct, which
passes behind the posterior edge of the mylo-hyoideus,
then runs along the inner surface of this muscle for-
GUIDE TO ANATOMY. 121
wards and upwards, on the inside of the sublingual
gland to open into the mouth on the side of the frenum
of the tongue.
The Sublingual Gland lies immediately above
the mylo-hyoideus, betwixt it and the internal mem-
brane of the mouth, where it lines the side and inferior
surface of the tongue. It sends off several ducts,
which open into the mouth between the root of the
tongue and side of the lower jaw. v
The removal of the mylo-hyoideus exposes a pair
of muscles, which are closely attached to one another.
13. The Genio-Hyoideus — Arises, tendinous, from
a projection on the inside of that part of the lower jaw
which is called the Chin; it descends, becoming
broader, and is
Inserted into the basis of the os hyoides.
Use: To draw the os hyoides forwards and upwards
to the chin.
By removing this muscle, or turning it back from
its origin from the jaw, we discover the next muscle.
14. The Genio-Hyo-Glossus — Arises, tendinous,
from a rough protuberance on the inside of the lower
jaw, higher up than the origin of the genio-hyoideus;
its fibres run forwards, upwards, and backwards, in a
very wide and radiated manner, to be
Inserted, some into the posterior part of the base of
the os hyoides, near its cornu, others into the tip,
middle, and root of the tongue.
This muscle lies under the genio-hyoideus before;
and more outwardly, under the mylo-hyoideus.
Use: According to the direction of its fibres, to draw
the tip of the tongue backwards into the mouth, the
middle downwards, and to render its dorsum concave;
to draw its root and the os hyoides forwards, and to
thrust the tongue out of the mouth.
It is called also Genio-glossus.
15. The Hyo-Glossus — Arises, broad and flesh v,
11
122 LONDON DISSECTOR, OR
from half of the base, and part of the cornu of the os
hyoides; the fibres run upwards, to be
Inserted into the side of the tongue.
It is situated more outwardly than the genio-hyo-
glossus, and, at its insertion into the tongue, mixes
with the stylo-glossus.
It moves the tongue inwards and downwards.
16. The Lingualis — Jlrises from the root of the
tongue laterally, and runs forwards between the hyo-
glossus and genio-hyo-glossus, to be
Inserted into the tip of the tongue, along with part
of the stylo-glossus.
Use: To contract the substance of the tongue, and
bring it backwards.
CHAPTER VIII.
DISSECTION OF THE MUSCLES ON
THE OUTSIDE OF THE THORAX.
In removing the integuments from the fore part of
the thorax, the pectoralis major and interior edge of
the deltoid muscle should be dissected in the course of
their fibres; and to do this, it will be necessary to
remember that the fibres run obliquely from the ster-
num and clavicle to the upper part of the os humeri.
They are not covered by any fascia, but by a con-
densed cellular membrane.
Three pair of muscles are described in this dissec-
tion.
I. The Pectoralis Major — Jlrises, tendinous,
from the anterior surface of the sternum, its whole
GUIDE TO ANATOMY. 123
length; fleshy, from the cartilages of the fifth, sixth,
and sometimes the seventh ribs, and from two anterior
thirds of the clavicle. The fleshy fibres run obliquely
across the breast, and, converging, form a strong flat
tendon, which is
Inserted into the outside of the bicipital groove of
the os humeri.
The clavicular and thoracic portions of the muscle
are separated by a line of cellular membrane. The
tendon is covered by the anterior edge of the deltoid;
it forms the anterior fold of the arm-pit, and appears
twisted; for the fibres, which proceed from the tho-
racic portion of the muscle, seem to pass behind those
proceeding from the clavicle, and to be inserted into
the os humeri somewhat higher up.
Use: to move the arm forwards, and obliquely
upwards, towards the sternum; or to draw it towards
the side.
The pectoralis major should be lifted up from its
origin, and suspended by its tendon. This will expose
the next two muscles.
2. The Pectoralis Minor — Arises, by three ten-
dinous and fleshy digitations, from the upper edges of
the third, fourth, and fifth ribs, near their cartilages; it
forms a fleshy triangular belly which becomes thicker
and narrower as it ascends, and is
Inserted, by a short flat tendon, into the anterior
part of the coracoid process of the scapula.
The belly of this muscle is covered by the pecto-
ralis major, the tendon passes under the anterior edge
of the deltoid, and is connected at its insertion with
the origins of the coraco-brachialis, and of the short
head of the biceps flexor cubiti, and also with the
ligamentum proprium scapulae anticum, a strong liga-
ment, which passes from the external edge of the
coracoid process, to be affixed to the posterior margin
of the acromion of the scapula.
124 LONDON DISSECTOR, OR
Use: To draw the scapula forwards and down-
wards, and, when that bone is fixed, to elevate the
ribs.
This muscle is called also Serratus minor anticus.
3. The Subclavius — Arises, by a flat tendon, from
the cartilage of the first rib, and forms a broad fleshy
belly, which is
Inserted into the inferior surface of the clavicle,
beginning about one inch from the sternum, and con-
tinuing as far as the ligamentous connection of the
clavicle to the coracoid process.
This muscle is situated between the clavicle and
sternum, and is concealed by the pectoralis major, and
the anterior part of the deltoid.
Use: to draw the clavicle downwards and forwards,
and perhaps to elevate the first rib.
Having lifted up the pectoralis minor from its origin,
the situation of the subclavian vessels which pass under
the clavicle, and over the first rib, may be seen.
OF THE PARTS WITHIN THE THORAX.
The cavity of the thorax may now be opened, by
cutting through the cartilages of the ribs on each side,
and separating the lower part of the sternum from the
diaphragm. That bone must then be lifted upwards
and removed, by separating it at its articulations with
the clavicle. This will allow us to examine more
readily the great vessels passing out of the thorax.
On looking under the sternum, while it is lifted up,
we see the Mediastinum, separating, as it is gradually
torn from the posterior surface of the sternum, into two
layers, and thus forming a triangular cavity. This
cavity is artificially produced, and is entirely owing to
the method of raising the sternum.
When the sternum is laid back or removed, the fol-
lowing parts are to be observed:
GUIDE TO ANATOMY. 125
The Mediastinum, now collapsed, dividing the
thorax into two distinct cavities, of which the right is
the largest.
The lungs of each side lying distinct in these
cavities.
The Pericardium, containing the heart, situated in
the middle of the thorax, between the two laminae of
the mediastinum, and protruding into the left side.
The internal surface of the pleura, smooth, colorless,
and glistening, lining the ribs, and reflected over the
lungs.
1. The Pleura. — Each side of the thorax has its
particular pleura. — The pleurae are like two bladders,
situated laterally with respect to each other, by ad-
hering together in the middle of the thorax, and pass-
ing obliquely * from the posterior surface of the ster-
num to the dorsal vertebrae, they form the mediasti-
num. — The pleura lines the ribs, and the upper surface
of the diaphragm, and is reflected over the lung, which
is in fact behind it; it forms the ligamentum latum pul-
monis, a reflection of this membrane, which connects
the inferior edge of the lungs to the spine and dia-
phragm.
2. The Lungs. — Reddish in children, greyish in
adults, and blue in old age. Their shape corresponds to
that of the thorax, being pyramidal, convex towards
the ribs, concave towards the diaphragm, and irregu-
larly flattened next the mediastinum.
The Right Lung is the larger, and is divided into
three lobes, two large ones, and an intermediate smaller
lobe.
The Left Lung has two lobes, and also a square notch
opposite the apex of the heart. Into the sulci or
* They run obliquely, not being in general attached to the middle of
the sternum, but towards its left side, especially at the lower part of the
bone, nearthe diaphragm. Besides the pericardium, the mediastinum coo-
tains betwixt its lamina; some adipose membrane and absorbent glands.
11*
126 LONDON DISSECTOR, OR
grooves which form the divisions of the lungs into
lobes, the pleura enters; that part of the lung which is
affixed to the spine, is called its root; through it the
great vessels enter.
3. The Pericardium is a strong, white, and com-
pact membrane, smooth and lubricated upon the inside,
forming a bag for containing the heart, and having its
inner lamina reflected over the substance of the heart
itself.
4. When you slit open the fore part of the pericar-
dium, you expose the Heart. The right ventricle
protrudes; the right auricle also is towards you; while
the left auricle is concealed, and only its tip is seen
lapping round upon the left ventricle. From under
this tip of the left auricle, a branch of the coronary
vein, and of the coronary artery, ramify towards the
apex of the heart, marking the situation of the septum
cordis. The left ventricle will be found firm, fleshy,
and resisting, whilst the right ventricle is more loose,
and seems partly wrapt round the other.
The heart is situated obliquely in the middle of the
breast; its posterior surface is flat, and lies upon the
diaphragm; its apex is turned forwards, and towards
the left side, so that, in the living body, it is felt striking
between the fifth and sixth ribs, at the point where the
cartilages and bony extremities are united. The Vena
Cava Superior is seen coming down from the upper
angle of the pericardium. The Inferior Cava is seen
coming up through the diaphragm; but only a very small
part of this vein is covered by the pericardium; the two
veins enter the right auricle. The Right Auricle is
turned forwards, and might be called the anterior; it
generally appears black,from the blood shining through
its thin coats. The Right Ventricle is situated
almost directly opposite. The Pulmonary Artery
arises from the right ventricle; its root is concealed
by the right auricle; it ascends on the left side of the
GUIDE TO ANATOMY. 127
aorta, and divides into the right and left pulmonary-
arteries: the right passes under the arch of the aorta,
crosses behind it and the vena cava superior to the
right lung, and is the longer, whilst the left pulmonary-
artery passes to the left lung, crossing the descending
aorta anteriorly. The Pulmonary Veins enter the
left auricle, two veins come from each lung; the right
veins are longer, because they pass behind the vena
cava superior. The left auricle is situated on the left
side of the right auricle, and somewhat behind it; its
tip is seen lapping round upon the Left Ventricle;
this is situated behind and on the left side of the right
ventricle; its substance is stronger and more firm to the
touch. The Aorta arises from the back part and
right side of the left ventricle; its root is covered by
the pulmonary artery; it then ascends betwixt that ar-
tery and the vena cava superior. Immmediately from
the root of the aorta, within the pericardium, the two
coronary arteries are sent oif to supply the heart itself.
As the Vena Cava Superior descends before the
root of the lungs, and on the right side of the aorta,
immediately before it perforates the pericardium, it
is joined upon its posterior part by the vena azygos,
which comes forwards from the spine, returning the
blood from the intercostal spaces.
Behind the sternum, and just above the arch of the
aorta, the superior cava is seen receiving two great
branches:
One from the right side, formed by the right subcla-
vian vein, and the right internal jugular; and another,
which is larger, from the left side; formed by the left
subclavian and the left internal jugular. This trunk
crossing in front of the arteries arising from the arch
of the aorta, enters the superior vena cava. Into the
posterior part of the angle formed by the union of the
left subclavian and the left jugular, the thoracic duct
empties itself.
128 LONDON DISSECTOR, OR
On each side of the neck, the internal jugular vein
will be seen descending by the side of the carotid,
while the subclavian vein comes from the arm.
The Vena Cava Inferior, immediately after pass-
ing through the diaphragm from the abdomen, enters
the pericardium.
The Aorta leaves the heart opposite the fourth
dorsal vertebra; it crosses over the pulmonary artery,
ascends obliquely upwards, backwards, and to the
right side, as high as the second dorsal vertebra. Here
it forms an Arch or incurvation, which passes from the
right to the left side, and at the same time obliquely
from before backwards; it then comes in contact with
the upper part of the third dorsal vertebra, and de-
scends along the spine in the posterior mediastinum.
This arch of the aorta is situated behind the first bone
of the sternum, behind and somewhat below the left
branch of the vena cava superior.
From the upper part of the arch come off three
large arteries:
The Arteria Innominata, or common trunk
of the right carotid and subclavian; the left carotid
and the left subclavian.
The student should observe also the Thymus gland;
a soft glandular body, lying before the lower part of
the trachea and the great vessels of the heart, a little
higher than the tops of the two pleurae. It is very
large in the fetus, smaller in adults, and nearly disap-
pears in the aged.
Where the aorta begins to descend, it is connected
to the pulmonary artery by a ligament, which, in the
foetus, was a large canal, the Ductus Arteriosus.
The heart may be now removed.
PISSECTJON OF THE HEART, WHEN REMOVED FROM
THE BODY.
The heart consists of three tunics or coats. 1 . An
external smooth one, which is a reflection of the inter-
GUIDE TO ANATOMY. 129
nal lamina of the pericardium. 2. A middle muscular
coat. 3. A smooth internal coat, which is a continua-
tion of the internal coat of the great veins and arteries.
In the right side of the heart we always meet with a
considerable quantity of coagulated blood. In the left
side there is much less.
Slit open with the scissors the two venae cava? on
their fore part; the inner surface of these veins, and of the
right auricle, will be seen lined by a smooth membrane;
and in the auricle, the musculi pectinati, or bundles of
muscular fibres, will be seen projecting. At the point
of union between the two cavae, there is a projection
formed by the thickening of the muscular coat, called
the Tuberculum Loweri. The Septum Auricu-
larum is seen separating the right from the left auri-
cle; — observe that it is thin, that in it there is an oval
depression, named Fossa Ovalis. Round this fossa
the fibres are thicker, forming the annulus ovalis; this
is the remains of the Foramen Ovale of the foetus; and
in many adult subjects a probe may be passed through
the superior part of the fossa obliquely into the left au-
ricle. The Valvula Nobilis, or Eustachian Valve,
is a membrane-like duplicature of the inner coat of
the auricle, observed where the vena cava inferior is
continued into the auricle, and stretching from that vein
towards the opening into the right ventricle. This
valve is sometimes found reticulated. Behind this valve
is the orifice of the Coronary Vein, with its small
valve.
The foramina Thebesii are minute orifices of veins,
which open into all the cavities of the heart; they are
most numerous, however, in the right auricle.
The Ostium Venosum, or opening of the right au-
ricle into the right ventricle, is somewhat oval; it has
a valve which projects into the right ventricle.
The Right Ventricle may now be opened by an
incision, carried from the root of the pulmonary artery
130 LONDON DISSECTOR, OR
down to the apex of the heart. This incision should
be made with care, lest the parts on fhe inside of the
ventricle he destroyed by it; it should pass along the
right side of the septum ventriculorum,the situationof
which is marked out by large branches of the coronary
artery and vein. A small opening should first be made,
into which one blade of the scissors can be introduced:
the incision may be continued through the apex of the
heart, or a flap may be made by another cut, passing
from the beginning of the first along the margin of the
right auricle. In this ventricle, observe the project-
ing bundles of muscular fibres, the Tricuspid Valves
arising from the margin of the ostium venosum, and
projecting into the right ventricle. This valve forms a
complete circle at its base, but has its edge divided
into three parts, which are attached by tendinous fila-
ments, named Chord/e Tending, to the Columns
Carne^e, or muscular bundles of the ventricle.
The Septum Ventriculorum, or partition of the
two ventricles, is marked out externally by two veins
running from the apex to the basis of the heart.
Slit up the pulmonary artery: observe how it arises
from the back part of the right ventricle, how smooth
the inside of the ventricle becomes as it approaches
the entrance of the artery, or ostium arteriosum. Ob-
serve the three Semilunar or Sigmoid Valves.
Their bases arise from the artery, their loose edges
project into its cavity, and in the middle of the loose
edge of each valve is seen a small white body, termed
Corpus Sesamoideum Auraritii. The artery is seen
bifurcating into the right and left pulmonary arteries,
and, just before its bifurcation, sending off to the aorta
the ductus arteriosus, which in the adult is a ligament.
The Left Auricle has four pulmonary veins
opening into its cavity, which may be exposed by slit-
ting up two of these veins. Observe that its coats are
thicker than those of the right auricle. The septum
GUIDE TO ANATOMY. 131
auricularum, with the fossa ovalis, is here seen less
distinctly than on the right side. Observe also the
ostium venosum, opening into the left ventricle, and
giving attachment to the Valvula Mitralis.
The Left Ventricle may be opened in the same
manner as the right, by an incision carefully made in
the left side of the septum or partition of the ventricles,
and continued round the upper part of the ventricle,
under the auricle. Observe the great thickness of the
muscular coat; the Valvula Mitralis, forming two
projections, which are attached by the chordae tendi-
neae to the fleshy columns of this ventricle.
Slit up the aorta; it has three semilunar valves, which
resemble those of the pulmonary artery: — behind these
valves the artery bulges out, forming the Sinuses of
the aorta. Above two of the valves lie the orfices of
the two coronaiy arteries; of which the left is the
larger.
CHAPTER IX.
DISSECTION OF THE MUSCLES OF
THE FACE.
Under the integuments of the face, there is always
a considerable quantity of adipose membrane; many of
the muscles are very slender, and, lying embedded in
this fat, require careful dissection. The whole side
of the face is also supplied with numerous ramifications
of the fascial nerve, or portio dura of the seventh pair.
These nervous twigs are generally removed with the
integuments.
Twelve pair of muscles, and one single muscle, are
described in this dissection.
132 LONDON DISSECTOR, OR
1 . The Orbicularis Palpebrarum or orbicularis
oculi — Arises, from the internal angular process of the
frontal bone, and from a tendon at the inner angle of
the eye, by a number of fleshy fibres which pass round
the orbit, covering first the superior, and then the
inferior eye-lid, and also the bony edges of the orbit.
Inserted, by a short round tendon, into the nasal
process of the superior maxillary bone.
This muscle is intermixed, at its upper part, with
the occipito-frontalis; it covers the upper part of the
lacrymal sac, and should be divided into the external
and internal muscles. The internal is the ciliaris
which covers the cartilages of the eye-lids, which
are called the Cilia or Tarsi.
Use: To shut the eye, by bringing down the upper
lid, and pulling up the lower; the fibres contracting
towards the inner angle, as to a fixed point, compress
the eye-ball and lacrymal gland, and convey the tears
towards the puncta lacrymalia.
2. The Corrugator Supercilii — Arises, fleshy,
from the internal angular process of the os frontis; it
runs outwards and a little upwards, to be
Inserted into the inferior fleshy part of the occipito-
frontalis muscle, extending outwards as far as the mid-
dle of the superciliary ridge.
This muscle is concealed by the occipito-frontalis.
It lies close to the upper and inner part of the orbicu-
laris palpebrarum, with which it is connected.
Use: To smooth the skin of the forehead, by pulling
it down after the action of the occipito-frontalis.
When it acts more forcibly, it pulls down the eye-
brow and skin of the forehead, and produces vertical
wrinkles.
3. The Compressor Naris — Arises, narrow, from
the outer part of the ala nasi, and neighbouring part
.of the os maxillare superius. From this origin a
GUIDE TO ANATOMY. 133
number of thin separate fibres run up obliquely along the
cartilage of the nose toward the dorsum nasi, where
the muscle joins its fellow, and is
Inserted, slightly, into the lower part of the os nasi
and nasal process of the superior maxillary bone.
It is superficial; its origin is connected with the
levator labii superioris alaeque nasi; and its upper part
with some of the descending fibres of the occipito-
frontalis.
Use: To compress the ala towards the septum nasi;
but, if the fibres of the occipito-frontalis, which
adhere to it, act, the upper part of this muscle assists
in drawing the ala outwards. It also corrugates the
skin of the nose.
4. Levator Labii Superioris Aundi Nasi —
Arises by two distinct origins; the first from the nasal
process of the superior maxillary bone, where it joins
the os frontis at the inner canthus of the eye; it
descends along the nasal process, and is inserted into
the outer part of the ala nasi, and into the upper lip.
The second arises, broad and fleshy, from the external
orbitar process of the superior maxillary bone, imme-
diately above the foramen infra-orbitarium; it runs
down, becoming narrower, and is inserted into the
upper lip and orbicularis oris.
The first portion of this muscle is sometimes called
Levator Labii Superioris Alaeque Nasi; and the
second, Levator Labii Superioris Proprius. Their
origins are partly covered by the orbicularis palpe-
brarum. They descend more outwardly than the ala
nasi.
Use: To raise the upper lip and dilate the nostril.
The infra-orbitary artery, vein, and nerve, are seen
emerging from the infra-orbitary foramen under this
muscle.
5. Zygomaticus Minor — (often wanting) Arises
12
134 LONDON DISSECTOR, OR
from the upper prominent part of the os malae, and,
descending obliquely downwards and forwards, is
Inserted into the upper lip near the corner of the
mouth.
Use: To draw the corner of the mouth and upper
lip obliquely upwards and outwards.
6. Zygomaticus Major — Arises, fleshy, from the
os malae, near the zygomatic suture.
Inserted into the angle of the mouth, appearing to
be lost in the depressor anguli oris, and orbicularis
oris.
Its origin is partially covered by the orbicularis
palpebrarum; it lies more outwardly than the zygo-
maticus minor.
Use: To draw the corner of the mouth and under
lip upwards and outwards.
7. The Levator Anguli Oris, or Levator labiorum
communis — Arises, thin and fleshy, from a depression
of the superior maxillary bone, between the root of
the socket of the first dens molaris, and the foramen
infra-orbitarium.
Inserted into the angle of the mouth.
It lies more outwardly than the levator labii supe-
rioris alaeque nasi, and is in part concealed by that
muscle, by the zygomaticus minor, and part of the
zygomaticus major. At its insertion it is particularly
connected with the depressor anguli oris.
Use: To draw the corner of the mouth upwards.
8. The Depressor Anguli Oris — Arises, broad
and fleshy, from the base of the maxillary bone, near
the chin, and, gradually becoming narrower, is
Inserted, into the angle of the mouth, uniting with the
zygomaticus major, and levator anguli oris: it is also
firmly connected with the platysma myoides.
Use: To pull down the corner of the mouth.
9. The Depressor Labii Inferioris, or Quad-
ratus Genae — Arises, fleshy and broad, from the side
GUIDE TO ANATOMV. 135
of the lower jaw, a little above its lower edge; it runs
obliquely upwards and inwards, and is
Inserted into the edge of the under lip.
This muscle, at its insertion, decussates with its
fellow. It is in part covered by the depressor anguli
oris, and forms the thick part of the chin, and has its
fibres interwoven with fat
Use: To pull the under lip downwards.
10. The Buccinator — Arises, tendinous and fleshy,
from the lower jaw, as far back as the root of the
coronoid process; from the upper jaw, as far back as
the pterygoid process of the sphenoid bone; it then con-
tinues to arise from the alveolar processes of both jaws,
as far forwards as the dentes cuspidati. The fibres
run forwards, and are
Inserted into the angle of the mouth.
This muscle lies deep, adheres to the membrane
that lines the mouth; and a quantity of fat is always
found between its fibres and the other muscles and
integuments. It is partly concealed by the masseter,
and by the muscles which pass to the angle of the
mouth, as the levator and depressor anguli oris, and
zygomaticus major. It is inserted behind these mus-
cles. In the cheek it is connected with the platysma
myoides, and is perforated by the duct of the parotid
gland.
Use: To draw the angle of the mouth backwards
and outwards, and to contract its cavity, by pressing
the cheek inwards.
The single muscle is the
Orbicularis Oris. — It consists of two planes of
semicircular fibres, which decussate at the angles of
the mouth. These fibres are formed chiefly by the
muscles which are inserted into the lips; they sur-
round the mouth. The superior portion runs along
the upper lip, the inferior along the lower.
It is connected and intermixed with the insertions
136 LONDON DISSECTOR, OR
of all the preceding muscles of the face. Some of
the fibres are connected to the septum nasi, and are
by Albinus termed Nasalis Labii Superioris.
Use: To shut the mouth, by contracting and draw-
ing both lips together; and to antagonize the muscles
inserted into the lips.
11. Depressor Labii Superioris Al^oue Nasi,
Arises, thin and fleshy, from the os maxillare supe-
rius, where it forms the alveoli of the dentes incisivi
and dens caninus; thence it runs up under part of the
levator labii superioris alaeque nasi.
Inserted into the upper lip and root of the ala nasi.
It is concealed by the orbicularis oris and levator
labii superioris alaeque nasi, but may be discovered
by inverting the upper lip, and dissecting on the side
of the frenum which connects the lip to the gums.
Use: To draw the upper lip and ala nasi down-
wards and backwards, and to compress the nostril.
12. The Levator Labii Inferioris or Superbus.
Arises from the lower jaw at the root of the alveolus
of the lateral incisor.
Inserted into the under lip and skin of the chin.
These two small muscles are found by the side of
the frenum of the lower lip. They lie under the
depressor labii inferioris.
Use: To raise the under lip and skin of the chin,
and to protrude the lip.
We have still remaining two strong muscles on the
side of the face, and two other muscles concealed by
the angle of the inferior maxilla.
1. The Masseter is divided into two portions,
which decussate one another.
The anterior portion arises, tendinous and fleshy,
from the superior maxillary bone, where it joins the
os malae; from the lower edge of the os mala?, and
from its zygomatic process. The strong fibres run
obliquely downwards and backwards, and are inserted
into the outside of the angle of the lower jaw.
GUIDE TO ANATOMY. 137
The Posterior portion arises, principally fleshy.
from the inferior surface of the os malae, and of the
whole of the zygomatic process, as far back as the
tubercle before the socket for the condyle of the
lower jaw. The fibres run forward, and are inserted,
tendinous, into the outer surface of the coronoid process
of the lower jaw.
The anterior portion conceals almost the whole of
the posterior. The greater part of this muscle is
superficial.
Use: To pull up the lower jaw, for performing the
grinding or lateral motions.
2. Temporalis — Arises, fleshy, from a semicircu-
lar ridge in the lower and lateral part of the parietal
bone, from all the squamous portion of the temporal
bone, from the external angular process of the os
frontis, from the temporal process of the sphenoid
bone, and from an aponeurosis which covers the mus-
cle. From these different origins the fibres converge,
descend under the bony jugum formed by the zygo-
matic processes of the temporal and cheek bones.
Inserted, by a strong tendon, into the upper part of
the coronoid process of the lower jaw, to which it
adheres on every side, but more particularly on its
anterior part.
Its insertion is concealed by the jugum and by the
masseter; so that, to expose it, the masseter must be
cut away.
Use: To raise the lower jaw.
To expose the following muscles, we must remove
those of the cheek and jaw; the masseter and the
insertion of the temporalis must be taken away, and
the coronoid process of the inferior maxilla removed
by a saw.
3. The Pterygoideus Exterxus — Arises, from
the outer side of the external plate of the pterygoid
process of the sphenoid bone, from part of the tube-
12*
138 LONDON DISSECTOR, OR
rosity of the os maxillare adjoining to it, and from the
root of the temporal process of the sphenoid bone.
It passes backwards and outwards, to be
Inserted into a depression in the neck of the condy-
loid process of the lower jaw, and into the anterior
and inner part of the ligament of the articulation of
that bone.
This muscle passes almost transversely from the
skull to its insertion. It is concealed by the muscles
of the face and neck, and by the ascending processes
of the lower jaw.
Use: When this pair of muscles act together, they
bring the jaw horizontally forwards. When they act
singly, the jaw is moved forwards, and to the oppo-
site side.
4. The Pterygoideus Internus — Jlrises, tendi-
nous and fleshy, from the inner and upper part of the
internal plate of the pterygoid process of the sphenoid
bone, filling all the space between the two plates; and
from the pterygoid process of the os palati between
these plates.
Inserted, by tendinous and fleshy fibres, into the
inside of the angle of the lower jaw.
To expose this muscle, the jaw must be removed
from its articulating cavity, and then pulled forwards,
and toward the opposite side; or it may be sawn
across at its sympyhsis, and the other half removed.
It is larger than the pterygoideus externus; and
betwixt the two muscles there is a considerable quan-
tity of cellular membrane, and the trunk of the inferior
maxillary and gustatory nerves. Like that muscle, it
is concealed by the lower jaw and facial muscles.
Along its posterior edge we observe the Ligamentum
Laterale Maxillae Inferioris, a ligamentous band, which
extends from the back part of the styloid process to
the angle of the lower jaw.
GUIDE TO ANATOMY. 139
Use: To draw the jaw upwards, and obliquely
towards the opposite side, or to move it laterally.
On the side of the face is situated a considerable
salivary gland, the Parotid Gland, a large white
mass, irregularly oblong and protuberant, filling up all
the space between the angle and the ascending pro-
cesses of the jaw, the mastoid process, root of the
cartilage of the ear, and zygomatic process of the
temporal bone. From its anterior and upper part a
white canal or duct passes forwards over the masse-
ter, and perforates the buccinator from without
inwards, opening into the mouth opposite the first
dens molaris. The coats of this duct are very thick
and firm, consisting of a ligamentous substance.
CHAPTER X.
DISSECTION OF THE THROAT.
On looking into the mouth, we observe a soft cur-
tain hanging from the palate bones, named the Velum
Pendulum Palati, or soft Palate. The apex of the
velum forms a small projecting glandular body, termed
the Uvula, or pap of the throat. From each side of
the Uvula, two muscular half arches or columns are
sent down, the anterior to the root of the tongue, the
posterior to the side of the pharynx. Between these
half arches on each side, are situated the glands termed
Amygdalae, or tonsils. The common opening behind
the anterior arch is named the Fauces, or Top of the
Throat, from which there are six passages, two up-
wards, being one to each nostril, called the Posterior
Nostrils; two at the sides, called Eustachian Tubes,
140 LONDON DISSECTOR, OR
passing on each side to the ear;* two downwards, of
which the anterior is the passage through the glottis
and larynx into the trachea; the posterior, which is the
largest, is the pharynx, or top of the oesophagus, and
leads to the stomach.
MUSCLES SITUATED ABOUT THE ENTRY OF THE
FAUCES.
These consist of four pairs, and a single muscle in
the middle.
1. Constrictor Isthmi Faucium — Arises, by a
slender beginning, from the side of the tongue, near
its root; thence running upwards within the anterior
arch, before the amygdala, it is
Inserted into the middle of the velum pendulum pal-
ati, as far as the root of the uvula. It is here connected
with its fellow, and with the beginning of the palato-
pharyngeus.
Situation: It forms the anterior half arch.
Use: To draw the velum towards the root of the
tongue, which at the same time it raises; and, with its
fellow, to contract the opening into the fauces.
2. The Palato-Pharyngeus — Arises, by a broad
beginning, from the root of the uvula in the middle of
the velum pendulum palati, and from the tendinous ex-
pansion of the circumflexus palati. The fibres pass
along the posterior arch behind the amygdala, and run
backwards to the superior and lateral part of the pha-
rynx, where they are scattered, and mixed with those
of the stylo-pharyngeus.
Inserted into the edge of the upper and back part of
* A probe may be introduced through the anterior nostrils into the
Eustachian tube; the tube opens into the pharynx in a direction opposite
to the space between the roots of the middle and inferior turbinated
bones.
GUIDE TO ANATOMY. 141
the thyroid cartilage, and into the back part of the
pharynx; thus forming the posterior half arch or
column.
Use: To draw the uvula and velum downwards and
backwards, and pull the thyroid cartilage and pharynx
upwards; to shut the passage into the nostrils, and, in
swallowing, to thrust the food from the fauces into the
pharynx.
The S alpin go-Pharyngeus of Albinus is composed
of a few fibres of this muscle, which arise from the an-
terior and lower part of the cartilaginous extremity of
the Eustachian tube, and are inserted into the inner part
of the last mentioned muscle.
3. The Circumflexus, or Tensor Palati, — Arises,
from the spinous process of the sphenoid bone, behind
the foramen ovale, and from the Eustachian tube near
its osseous part; it runs down along the pterygoideus
internus, and forms a round tendon, which passes over
the hook of the internal plate of the pterygoid process
of the sphenoid bone, and soon spreads into a broad
tendinous expansion.
Inserted into the velum pendulum palati, and semi-
lunar edge of the os palati.
Its insertion extends as far as the suture which joins
the two ossa palati. Some of its posterior fibres
generally join with the constrictor pharyngis superior
and palato-pharyngeus.
Use: To stretch the velum, and draw it downwards,
and to one side.
4. The Levator Palati — Arises, tendinous and
fleshy, from the extremity of the petrous portion of
the temporal bone, and from the Eustachian tube.
Inserted into the whole length of the velum pendu-
lum palati, as far as the root of the uvula, uniting with
its fellow.
Ust: To draw the velum upwards and backwards,
142 LONDON DISSECTOR, OR
so as to shut the passage from the fauces into the
mouth and nose.
The single muscle is the
Azygos Uvulae. — It arises, fleshy, from the extrem-
ity of the suture which unites the ossa palati; runs
down the whole length of the velum, like a small
earth-worm, adhering to the tendons of the circum-
flexi palati.
Inserted into the tip of the uvula.
Use: To raise the uvula upwards and forwards, and
shorten it.
MUSCLES ON THE BACK PART OF THE PHARYNX.
Of these there are three pair.
1. The Constrictor Pharyngis Inferior. This
muscle arises, from the outside of the ala of the
thyroid cartilage, near the attachment of the thyro-
hyoideus muscle, and from the side of the cricoid
cartilage, near the crico-thyroideus.
Inserted into the white line on the back part of the
pharynx, where it is united to its fellow.
This muscle covers the under part of the middle
constrictor; the superior fibres run obliquely upwards,
while the inferior fibres have a transverse direction,
and surround the oesophagus.
Use: To compress that part of the pharynx which
it covers, and to raise it with the larynx a little
upwards.
2. The Constrictor Pharyngis Medius — Arises
from the superior edge of the cornu of the os hyoides,
extending as far forwards as the graniform process, or
appendix; and from the ligament which connects the
os hyoides to the thyroid cartilage. The superior
fibres ascend obliquely, the others run more trans-
versely.
Inserted into the cuneiform process of the os occip-
itis, before the foramen magnum, and into a white
GUIDE TO ANATOMY. 143
line in the middle of the posterior surface of the
pharynx, where it is joined to its fellow.
The lower part of this muscle is covered by the
muscle last described, while the upper part covers the
inferior fibres of the constrictor superior.
Use: To compress that part of the pharynx which
it invests, and to draw it and the os hyoides upwards.
3. Constrictor Pharyngis Superior — Arises,
above, from the cuneiform process of the os occipitis,
before the foramen magnum; lower down from the
pterygoid process of the sphenoid bone; from the
upper and under jaw, near the alveolar processes of
the last dentes molares; and from the back part of the
buccinator muscle. Some fibres also come from the
root of the tongue, and from the palate.
Inserted into a white line in the middle of the pos-
terior surface of the pharynx.
The larger part of this muscle is covered by the
constrictor medius.
Use: To compress the upper part of the pharynx,
and draw it forwards and upwards.
MUSCLES OF THE LARYNX.
The Larynx is composed of five Cartilages: 1 . The
Thyroid Cartilage, situated immediately below the
os hyoides in the middle of the throat. 2. The Cri-
coid Cartilage, situated immediately below the thy-
roid cartilage, betwixt it and the superior rings of
the trachea. 3. The Epiglottis, a broad triangula
cartilage, very elastic, situated behind the root of th«
tongue, and covering the entrance into the upper part
of the larynx. 4 & 5. The arytenoid cartilages, two
small bodies, like peas, situated behind the thyroid
cartilage, on the upper edge of the back part of the
cricoid cartilage, and between the two alas or wings
of the thyroid cartilage. These two small cartilages
144 LONDON DISSECTOR, OR
form between themselves and the thyroid a longitu-
dinal fissure, extending from before backwards, which
is called the Glottis, or Rima Glottidis, and leads to
the trachea.
The muscles situated about the glottis consist of
four pairs of small muscles, and a single one.
1. The Crico-Aryt.<enoideus Posticus — Arises,
fleshy, from the posterior part of the cricoid cartilage.
Inserted, narrow, into the back part of the aryte-
noid cartilage of the same side.
Use: To open the rima glottidis a little, and, by
pulling back the arytenoid cartilage, to render the
ligament of the glottis tense.
2. The Crico-Arytjenoideus Lateralis — Arises,
fleshy, from the side of the cricoid cartilage, where
it is covered by the ala of the thyroid cartilage.
Inserted into the outer side of the arytenoid carti-
lage, lying more forward than the last described
muscle.
Use: To open the rima glottidis, by pulling the
ligaments from each other.
3. The Thyro-Aryt^noideus — Arises from the
middle and inferior part of the posterior surface of
the thyroid cartilage; runs backwards, and a little
upwards, and is
Inserted into the fore part of the arytenoid carti-
lage, farther forward than the muscle last described.
Use: To pull the arytenoid cartilage forwards, and
thus shorten the ligament of the larynx or glottis.
4. Aryt^noideus Obliouus — Arises from the base
of one arytenoid cartilage; and, crossing its fellow, is
Inserted into the tip of the other arytenoid carti-
lage.
Use: When both act, they pull the arytenoid carti-
lages towards each other.
The single muscle is the
Aryt^noideus Transversus, which arises from
GUIDE TO ANATOMY. 145
the whole length of one arytenoid cartilage, and passes
across to be
Inserted into the whole length of the other arytenoid
cartilage.
It is situated anterior to the arytaenoidei obliqui.
Use: To shut the rima glottidis, by bringing the
arytaenoid cartilages together:
On each side of the larynx, there are also a few mus-
cular fibres, which are named as follows.
1 . Thyro-Epiglottideus — Arising, by a few pale
separated fibres from the thyroid cartilage, and
Inserted into the side of the epiglottis.
Use: To draw the epiglottis obliquely downwards,
or, when both muscles act, directly downwards; and
at the same time to expand it.
2. The Aryteno-Epiglottideus — Arises, by a
few slender fibres, from the lateral and upper part of
the arytaenoid cartilage, and is
Inserted into the epiglottis, along with the former
muscle.
Use: When both muscles act, to pull the epiglottis
close upon the glottis.
13
CHAPTER XI.
DISSECTION OF THE ORBIT OF
THE EYE.
The globe or ball of the eye is situated about the
middle of the orbit. It is connected to the bone by its
muscles, and by the optic nerve; and all these parts are
embedded posteriorly in a soft, fatty substance, which
fills up the bottom of the orbit. The tunica, or mem-
brana conjunctiva, is seen lining the inner surface of
the eye-lids, and reflected from them over the anterior
part of the globe of the eye, so that the back part of the
eye-ball, and all the muscles and nerves, are situated
behind it. This membrane must therefore be dissected
away; the upper part of the orbit, which is formed by
the os frontis, must be removed with a saw, and the
fat surrounding the muscles, vessels, and nerves, cau-
tiously dissected away with the scissors.
MUSCLES SITUATED WITHIN THE ORBIT.
Seven muscles are contained within the orbit, of
which one belongs to the upper eye-lid, and six to the
globe of the eye.
1. The Levator Palpebbje Superioris — Jlriscs,
by a small tendon, from the upper part of the foramen
opticum of the sphenoid bone; the tendon forms a broad
flat belly.
Inserted, by a broad thin tendon, into the upper eye-
lid, adhering to the tarsal cartilage, which gives form
to the eye-lid.
GUIDE TO A>*ATOMV. 147
Use: To open the eye, by drawing the superior
eye-lid upwards.
There are four straight muscles, or recti, belonging
to the globe of the eye. These four muscles resemble
each other, all arising by narrow tendons from the mar-
gin of the foramen opticum, where they surround the
optic nerve; all forming strong fleshy bellies, and in-
serted, by broad, thin tendons, at the fore part of the
globe of the eye, into the tunica sclerotica, or outer
tunic of the eye, and under the tunica conjunctiva.
They are distinguished from each other by the terms
Levator, Depressor, Abductor and Adductor.
2. The Levator Oculi — Arises, by a narrow ten-
don, from the upper part of the foramen opticum of the
sphenoid bone; it forms a fleshy belly, and is
Inserted into the superior and anterior part of the
tunica sclerotica, by a broad thin tendon.
It lies below the levator palpebral superioris, and
raises the globe of the eye.
3. The Depressor Oculi — Arises from the inferior
margin of the foramen opticum, and is
Inserted into the inferior and anterior part of the tu-
nica sclerotica.
Use: To move the globe of the eye downwards.
4. The Adductor Oculi — Arises from the inner
part of the foramen opticum, and is
Inserted into the inner and anterior part of the tunica
sclerotica.
It is the shortest of the four recti muscles, and draws
the eye towards the nose.
5. The Abductor Oculi — Arises from the outer
part of the foramen opticum.
Inserted into the outer part of the tunica sclerotica.
It is the longest of the recti, and moves the globe
outwards.
The next two are the oblique muscles.
148 LONDON DISSECTOR, OR
6. The Obliquus Superior, or Trochlearis, Jlrises,
by a small tendon, from the margin of the foramen op-
ticum, between the levator and abductor oculi. Its
long slender belly runs along the inner side of the orbit
to the internal angular- process of the os frontis, where
a cartilaginous pulley is fixed. The muscle then forms
a tendon, which passes through the pulley, runs ob-
liquely downwards and outwards, inclosed in a mem-
branous sheath; and becoming broader and thinner, is
Inserted into the tunica sclerotica, about half way
between the insertion of the levator oculi, and the
entrance of the optic nerve.
Use: To roll the globe of the eye, and turn the
pupil downwards and outwards.
7. The Obliq,uus Inferior — Jlrises, narrow, and
principally tendinous, from the outer edge of the
orbitar process of the superior maxillary bone, near
its junction with the os unguis. It runs obliquely out-
wards and backwards, under the depressor oculi, and is
Inserted, by a broad thin tendon, into the sclerotica,
between the entrance of the optic nerve, and the
insertion of the abductor oculi.
Use: To draw the globe of the eye forwards,
inwards, and downwards, and to turn the pupil upwards.
In the orbit, we also meet with the Lachrymal
Gland. — This gland is of a yellowish color; it is situ-
ated in a depression of the os frontis near the temple.
It adheres closely to the fat which surrounds the mus-
cles and posterior convexity of the eye. It sends off
several small ducts which pierce the tunica conjunctiva
lining the upper eye lid; these ducts cannot be seen,
unless the part be macerated in water, when they are
filled with the liquid.
The Puncta Lachrvmalia are two small holes
near the internal angle of the palpebrae, situated one
in each eye-lid. They lead into the Lachrymal Sac
GUIDE TO ANATOMV. 149
This sac is an oblong membranous bag, situated at the
inner angle of the eye, in a depression formed by the
os unguis, and nasal process of the superior maxillary
bone. It receives the tears by the puncta lachrymalia,
and from the sac they are conveyed into the nose by a
Duct, named the Lachrymal, or Nasal. The lower
extremity of this duct opens into the nose on one side
of the antrum maxillare, and under the os spongiosum
inferius. A probe, with its extremity bent, may be
introduced from the nose through this duct into the
lachrymal sac.
The Caruncula Lachrymalis is a small reddish
granulated body, situated at the internal angle of the
palpebral
CHAPTER XII.
DISSECTION OF THE MUSCLES ON
THE POSTERIOR PART OF THE
TRUNK AND NECK.
From the number and intimate connection of these
muscles, their description is necessarily complicated,
and their dissection difficult. The smaller muscles,
indeed, cannot be separated without dividing some of
their fibres. We do not here, as in the limbs, find the
muscles distinctly marked, loosely connected by
cellular membrane, and separated with facility; but
closely united, and in many places having their fibres
so intermixed, as to render their divisions indis-
tinct and uncertain.
In this dissection we meet with twenty-two distinct
pairs of muscles, besides a number of small muscles
situated between the processes of contiguous vertebrae.
13*
150 LONDON DISSECTOR, OR
On removing the integuments of the posterior part
of the neck and back, which may be done by making-
an incision along the whole length of the spine, another
from the tubercle of the occipital bone to the acromion,
and a third from the acromion to the last dorsal ver-
tebra; we expose,
1 . The Trapezius, or Cucullaris. — It arises, by
a thick round tendon, from the lower part of the pro-
tuberance in the middle of the os occipitis behind, and,
by a thin tendinous expansion, from the superior trans-
verse ridge of that bone; from the five superior cervi-
cal spinous processes by the ligamentum nuchas; tendi-
nous, from the two inferior cervical spinous processes,
and from ihe spinous processes of all the vertebras
of the back. The fleshy fibres coming from the neck
descend obliquely, while those from the back ascend.
Inserted, fleshy, into the posterior third part of the
clavicle; tendinous and fleshy, into the acromion, and
into the upper edge of all the spine of the scapula. The
fibres slide over a triangular surface at the extremity
of the spine of that bone.
Situation: This muscle is quite superficial, and con-
ceals all the muscles situated in the posterior part of
the neck, and upper part of the back. It adheres to
its fellow the whole length of its origin. Its anterior
fibres lie posterior to those of the sterno-mastoideus,
but are not in contact with them, a considerable quan-
tity of adipose substance being interposed. The pos-
terior cervical ligament (ligamentum nuchas vel colli)
is a ligament which arises from the middle of the
occipital bone, runs down on the back part of the neck,
adhering to the spinous processes of the cervical ver-
tebras, and giving origin to the fibres of the trapezius,
and of other muscles.
Use: To move the scapula in different directions.
The superior fibres draw it obliquely upwards, the
middle transverse ones draw it directly backwards.
GUIDE TO ANATOMY. 151
and the inferior fibres move it obliquely donwnwards
and backwards. Also, to draw back the head, and
contribute to its rotatory motions.
This muscle should now be reflected from the spine
and head.
2. The Latissimus Dorsi — Arises, by a broad thin
tendon, from all the spinous processes of the os sacrum,
and of the lumbar vertebrae; from the spinous processes
of the seven inferior dorsal vertebrae; from the poste-
rior part of the spine of the os ilium; also from the ex-
tremities of the four inferior false ribs, by four distinct
fleshy dictations, which intermix with those of the
obliquus externus abdominis. The inferior fleshy
fibres ascend obliquely; the superior run transversely:
they pass over the inferior angle of the scapula (from
which the muscle often receives a thin fasciculus of
fibres,) to reach the axilla, where they are all collected
and twisted.
Inserted, by a strong flat tendon, into the inner edge
of the groove in the os humeri, which receives the long
tendon of the biceps flexor cubiti.
Where this muscle arises from the dorsal vertebrae,
it is concealed by the origin of the trapezius. The
remainder of it is placed immediately under the skin,
and covers the deeper seated muscles of the loins and
back. It is situated superior to the gluteus maximus,
and posterior to the obliquus externus abdominis. Its
insertion cannot be traced till the muscles of the arm
are dissected; it forms the fold on the posterior part of
the hollow of the arm pit. The tendon of this muscle,
with the subjacent tendon of the serratus posticus
inferior, assists in forming the fascia lumborum.
Use: To pull the arm backwards and downwards,
and to roll the os humeri.
Having removed the trapezius and latissimus dorsi,
two muscles will be seen passing from the neck to the
scapula.
152 , LONDON DISSECTOR, OR
3. The Rhomboideus. This muscle is divided into
two portions, rhomboideus major and minor.
Rhomboideus major (the inferior portion) arises, ten-
dinous, from the spinous processes of the four or five
superior dorsal vertebras.
Inserted into all the base of the scapula below its
spine.
Rhomboideus minor (the superior portion) arises,
tendinous from the spinous processes of the three in-
ferior vertebrae of the neck, and from the ligamentum
nuchas.
Inserted into the base of the scapula, opposite to the
triangular plain surface at the root of the spine.
Situation: This muscle lies beneath the trapezius
and latissimus dorsi; a small part of the rhomboideus
major may be seen between these muscles, and the
inferior part of the base of the scapula.
Use: To draw the scapula obliquely upwards, and
directly backwards.
The rhomboidei should now be reflected from the
spine.
4. The Levator Scapulas — Arises from the trans-
verse processes of the five superior vertebrae of the
neck, by fi^£ distinct, tendinous, and fleshy slips, which
unite and form a considerable muscle.
Inserted, tendinous and fleshy, into the base of the
scapula, above the root of the spine, and under the
superior angle (not into the angle itself, as it is usually
described.)
This muscle is concealed by the trapezius and ster-
no-mastoideus; but a small part of its belly may be
seen in the space between the edges of these muscles.
The origin of the levator scapulae is partly cocealed
by the splenius capitis; and the digitations, where they
arise from the transverse processes, lie betwixt similar
attachments of the scaleni muscles before, and of the
splenius colli behind.
GUIDE TO ANATOMY. 153
Use: To draw the scapula upwards, and a little
forwards.
Detaching the rhomboideus from its origin in the
spine, you will see another muscle passing from the
whole of the basis of the scapula.
5. The Serratus Magnus, or Serratus Major An-
ticus — Jirises by nine fleshy digitations, from the nine
superior ribs. These digitations are seen on the
•anterior part of the thorax; they pass obliquely
backwards, and form a strong fleshy muscle.
Inserted, principally fleshy, into the whole of the
base of the scapula.
This muscle lies between the scapula and the ribs,
so that, to see its course, the articulation of the clavi-
cle to the sternum should be divided, and the scapula
lifted from the trunk. It is concealed by the latissimus
dorsi, by the two pectoral muscles, and the scapula.
The only part of it which can be seen before the
removal of those muscles, projects betwixt and below
them on the side of the trunk. The lower digitations,
which pass more anteriorly than the edge of the latis-
simus dorsi, are intermixed with the superior digita-
tions of the obliquus externus abdominis. The superior
digitations arise behind the pectoralis minor. The
insertion of the muscle is between the subscapularis,
which arises from the internal surface of the scapula,
and the insertions of the rhomboideus and levator
scapulae.
Use: To move the scapula forwards, and, when the
scapula is forcibly raised, to draw the ribs upwards.
The upper extremity may now be removed from the
trunk.
The removal of the rhomboideus also exposes,
6. The Serratus Superior Posticus. This mus-
cle arises, by a thin broad tendon, from the spinous
processes of the three inferior cervical vertebra?, and
of the two superior dorsal.
154 LONDON DISSECTOR, OR
Inserted, by distinct fleshy slips, into the second,
third, fourth, and sometimes the fifth ribs, a little
beyond their angle.
This muscle is concealed by the rhomboideus and
scapula, except a few of its superior fibres, which
appear above the upper edge of the rhomboideus
minor. It covers part of the origin of the splenius.
Use: To elevate the ribs, and dilate the thorax.
Reflect it from the spine.
7. The Splenius is divided into two portions:
(1.) The Splenius Capitis — Jlrises, tendinous, from
the spinous processes of the two superior dorsal, and
five inferior cervical vertebrae. It forms a flat broad
muscle, which ascends obliquely, and is inserted, ten-
dinous, into the posterior part of the mastoid process,
and into a small part of the os occipitis, immediately
below its superior transverse ridge.
This muscle is covered by the trapezius, and by the
insertion of the sterno-cleido-mastoideus, and a small
part of it is seen on the side of the neck betwixt those
two muscles. The lower part of its origin is covered
by the serratus superior posticus.
Reflect it from the occiput.
(2.) The Splenius Colli — Arises, tendinous, from the
spinous processes of the third, fourth, fifth, and some-
times the sixth dorsal vertebras. It forms a small
fleshy belly, which ascends by the side of the verte-
bras, and is inserted into the transverse processes of
the four or five superior cervical vertebras, by distinct
tendons, which lie behind similar tendons of the leva-
tor scapulae.
This muscle is concealed by the serratus superior
posticus, and splenius capitis.
Use: To bring the head and upper vertebrae of the
neck obliquely backwards. When both muscles act,
they pull the head directly backwards.
Reflect it from the dorsal vertebrae.
GUIDE TO ANATOMY. 155
8. The Serbatus Posticus Inferior — Arises, by
a broad thin tendon, from the spinous processes of the
two or three inferior dorsal vertebrae, and from the
three superior lumbar spines by the fascia lumborum.
Inserted, by distinct fleshy slips, into the lower
edges of the four inferior ribs, at a little distance from
their cartilages.
This is a thin muscle, of considerable breadth,
situated at the lower part of the back, under the
middle of the latissimus dorsi.
Use: To pull the ribs downwards and backwards.
Reflecting it from the spine, you expose the Fascia
Lumborum. It is a tendinous fascia, arising from the
lumbar vertebrae and os sacrum, giving origin to the
lower part of the serratus posticus inferior, and to the
posterior fibres of the obliquus internus and transver-
salis abdominis. It is also connected with the tendon
of the latissimus dorsi.
On detaching from the spine, this fascia, and the
serratus posticus inferior, we expose a thick muscular
mass, filling up all the space betwixt the spinous pro-
cesses of the vertebrae, and the angles of the ribs.
This mass consists of three muscles:
The Sacro-Lumbalis on the outside, the Longissi-
mus Dorsi in the middle, and the Spinalis Dorsi close
to the spinous processes.
These three muscles are closely connected together,
so that, to effect their separation, it is necessary to
divide some of the fibres.
9 and 10. The Sacro-Lumbalis and Longissimus
Dorsi — Arise, by one common origin, tendinous
externally, and fleshy internally, from the spinous
processes and posterior surface of the os sacrum; from
the posterior part of the spine of the os ilium; from
the spinous processes, and from the roots of the
transverse processes of all the lumbar vertebrae.
The thick fleshy belly, formed by this extensive
156 LONDON DISSECTOR, OR
origin, ascends, and, opposite to the last rib, divides
into the two muscles.
The sacro-lumbalis is inserted into all the ribs near
their angles, by long and thin tendons. The tendons
which pass to the superior ribs, are longer, ascend in
nearly a straight line, and are situated nearer to the
spine than those which pass to the lower ribs. On
separating the inner edge of this muscle (i. e. the edge
next to the spine) from the latissimus dorsi, and turn-
ing the belly towards the ribs, we see six or eight small
tendinous and fleshy bundles, which pass from the
inner side of this muscle, to be inserted into the upper
edge of the six or eight inferior ribs. These are called
the Musculi Accessorii ad Sacro-Lumbalem.
Use: To pull the ribs downwards, to assist in erect-
ing the trunk of the body, and in turning it to one side.
The longissimus dorsi is inserted into all the ribs
except the two inferior, betwixt their tubercles
and angles, by slips which are tendinous and fleshy,
and into the transverse processes of all the dorsal
vertebrae by small double tendons. The insertions in
the ribs proceed from the outer side of the muscle,
while the attachments to the transverse processes are
seen on separating the longissimus dorsi from the spi-
nalis dorsi.
Use: To extend the vertebras, and keep the body
erect.
1 1 . The Spinalis Dorsi is much smaller than the
last two muscles; below, it cannot be separated from
the longissimus dorsi, without dividing some fibres; it
lies betwixt that muscle and the spine.
Arises, tendinous, from the spinous processes of the
two superior lumbar vertebrae, and of the three inferior
dorsal.
Inserted into the spinous processes of the vertebrae
of the back, from the second to the ninth, by as many
distinct tendons.
GUIDE TO ANATOMY. 157
Use: To extend the vertebrae, and to assist in
raising the spine.
The three last described muscles are covered
below by the serratus posticus inferior and the latis-
simus dorsi; above, by the rhomboideus, serratus
superior posticus, and trapezius.
12. The Cervicalis Descenders — Arises, from
the upper edge of the four or five superior ribs, by as
many distinct tendons. It forms a small belly, which
ascends upwards, and is
Inserted, by three distinct tendons, into the trans-
verse processes of the fourth, fifth, and sixth cervical
vertebrae, between the splenius colli and levator scap-
ulae. This muscle is small, and is frequently de-
scribed as an appendage to the sacro-lumbalis.
Use: To turn the neck obliquely backwards.
13. The Transversalis Colli — Arises from the
transverse processes of the five superior dorsal verte-
brae, by five tendinous and fleshy slips, and is
Inserted, tendinous, into the transverse processes of
the five or six inferior cervical vertebrae.
The origin of this muscle lies on the inside of the
longissimus dorsi, and it is sometimes considered as an
appendage to it. The insertion is situated between the
cervicalis descendens and the trachelo-mastoideus.
Use: To turn the neck obliquely backwards, and a
little to one side.
14. The Trachelo-Mastoideus lies nearer to the
bone than the last described muscle.
Arises from the transverse processes of the three
uppermost vertebrae of the back, and of the five
inferior of the neck, by thin tendons, which unite
and form a fleshy belly.
Inserted, tendinous, into the posterior surface of the
mastoid process.
This muscle lies on the outside of the complexus,
and on the inside of the transversalis colli: its insertion
14
158 LONDON DISSECTOR, OR
is concealed by the splenitis capitis; it is covered also
by the levator scapulae.
Use: To keep the head and neck erect, and to draw
the head backwards, and to one side.
15. The Complexus — Arises, by tendinous and
fleshy fibres, from the transverse processes of the
seven superior dorsal, and of the four or five inferior
cervical vertebrae. It forms a thick, tendinous, and
fleshy belly.
Inserted, tendinous and fleshy, into the hollow
betwixt the two transverse ridges of the os occipitis,
extending from the middle protuberance of that bone,
nearly as far as the mastoid process.
This is a large muscle. Its origin from the cervical
vertebrae is nearer to the spine than the trachelo-mas-
toideus; and in the back, it arises nearer to the spine
than the transversalis colli; it is covered by the sple-
nius; but a large portion of it is seen between the
splenius and spine, immediately on removing the
trapezius.
Use: To draw the head backwards and to one side.
On removing the complexus from the occiput, we
find, close to the spine,
16. The Semi-Spinalis Colli. — It arises by dis-
tinct tendons, from the transverse processes of the six
superior dorsal vertebrae, ascends obliquely close to
the spine, and is
Inserted into the spinous processes of all the verte-
bras of the neck, except the first and last.
This muscle is situated close to the vertebrae at the
posterior part of the neck and back. It arises on the
outside of the semi-spinalis dorsi; its greater part is
concealed by the complexus and longissimus dorsi;
and the part which projects between these muscles,
is concealed by the serratus superior posticus.
Use: To extend the neck obliquely backwards.
17. Semi-Spinalis Dorsi — Arises from the trans-
GUIDE TO ANATOMY. 159
verse processes of the seventh, eighth, and ninth ver-
tebrae of the back, by distinct tendons which soon
grow fleshy.
Inserted, by distinct tendons, into the spinous pro-
cesses of the five superior dorsal vertebras, and of the
two lower cervical.
This muscle lies nearer the spine than the lower
part of the semi-spinalis colli; its inferior origins lie
on the outside of the insertion of the spinalis dorsi.
Use: To extend the spine obliquely backwards.
The removal of the complexus brings also into view
several small muscles, situated at the superior part of
the neck, immediately below the occiput
18. The Rectus Capitis Posticus Major —
Arises, fleshy, from the side of the spinous process of
the dentata. It ascends obliquely outwards, becoming
broader, and is
Inserted, tendinous and fleshy, into the inferior
transverse ridge of the os occipitis, and into part of
the concavity above that ridge.
Use: To extend and pull the head backwards, and
to assist in its rotation.
19. The Rectus Capitis Posticus Minor —
Arises, tendinous and narrow, from an eminence in the
middle of the back part of the atlas. It becomes
broader, and is
Inserted, fleshy, into the inferior transverse ridge
of the os occipitis, and into the surface betwixt that
ridge and the foramen magnum.
It is partly covered by the rectus capitis posticus
major, but a large portion of this pair of muscles is
seen projecting between the recti majores, and is
situated beneath the complexus.
Use: To draw the head backwards.
20. Obliqxus Capitis Superior — Arises, tendi-
nous, from the upper and posterior part of the trans-
verse process of the first cervical vertebra.
160 LONDON DISSECTOR, OR
Inserted, tendinous and fleshy, into the inferior
transverse ridge of the os occipitis behind the mastoid
process, and into a small part of the surface above and
below that ridge.
Use: To draw the head backwards, and to assist
in rolling it.
21. Obliq.uus Capitis Inferior — Arises, from the
side of the spinous process of the dentata, forms a thick
belly, and is
Inserted into the under and back part of the trans-
verse process of the atlas.
Use: To rotate the head, by turning the first ver-
tebra upon the second.
22. The Multifidus Spins.
On removing the muscles of the spine which have
been described, we find situated beneath them the
Multifidus Spinas. It is that mass of flesh which lies
close to the spinous and transverse processes of the
vertebras, extending from the dentata to theos sacrum.
The bundles of which it is composed seem to pass from
the transverse, to be inserted into the spinous processes.
Arises, tendinous and fleshy, from the spinous pro-
cesses and back part of the os sacrum, and from the
posterior adjoining part of the os ilium; from the ob-
lique and transverse processes of all the lumbar verte-
brae; from the transverse processes of all the dorsal
vertebrae; and from those of the cervical vertebra,
excepting the first three. The fibres arising from this
extensive origin pass obliquely, to be
Inserted, by distinct tendons, into the spinous pro-
cesses of all the vertebrae of the loins and back and
neck, except the atlas. The fibres arising from each
vertebra are inserted into the second one above it,
and sometimes more.
Use: To extend the back obliquely, or move it to
one side. When both muscles act, they extend the
vertebrae backwards.
GUIDE TO ANATOMY. 161
The small muscles situated between the processes
of the vertebrae are,
1 . Interspinales colli, dorsi, et lumborum. These
are small bundles of fibres, which fill up the spaces
between the spinous processes of the vertebrae. Each
of these little muscles arises from the surface of one
spinous process, and is inserted into the next spinous
process.
In the neck they are large, and appear double, as
the spinous processes of the cervical vertebrae are
bifurcated. In the back and loins they are indis-
tinct, and are rather small tendons than muscles.
Use: To draw the spinous processes nearer to each
other.
2. The Intertransversalis colli, dorsi, et lum-
borum, are small muscles which fill up, in a similar
manner, the spaces between the transverse processes
of the vertebrae. In the neck they are bifurcated and
distinct; in the back they are small and slender, and in
the loins they are strong and fleshy.
Use: To draw the transverse processes toward*
each other.
14*
CHAPTER XIII.
DISSECTION OF THE MUSCLES SITU-
ATED BETWEEN THE RIBS, AND
ON THE INNER SURFACE OF
THE STERNUM.
The muscles which fill up the space between;
the ribs are named Intercostals; they are disposed on
each side of the thorax in two layers; and each layer
consists of eleven muscles.
The Intercostales Externi — Arise from the
inferior acute edge of each superior rib, extending
from the spine to near the junction of the ribs with'
their cartilages. The fibres run obliquely forwards
and downwards, and are
Inserted into the upper obtuse edge of each inferior
rib, from the spine to near the cartilage of the rib.
These muscles are seen on removing the muscles
which cover the thorax.
The Levatores Costarum are twelve small
muscles, situated on each side of the dorsal vertebrae.
They are portions of the external intercostals. Each
of these small muscles arises from the transverse pro-
cess of one of the dorsal vertebras, and passes down-
wards, to be inserted into the upper side of the rib next
below the vertebra, near its tuberosity.
The first of these muscles passes from the last cer-
vical vertebra, the eleven others from the eleven
superior dorsal vertebrae. The three or four inferior
Levatores are longer, and run down to the second rib
GUIDE TO ANATOMY. 163
below the transverse process from which they arise.
Hence Albinus names them the Levatores Costarum,
Longiores et Breviores.
2. The Intercostales I>tern'i — Arise from the
inferior acute edge of each superior rib, beginning at
the sternum, and extending as far as the angle of the
rib. The fibres run obliquely downwards and back-
wards, and are
Inserted into the superior obtuse edge of each infe-
rior rib from the sternum to the angle. Portions of
the internal iutercostals pass over one rib, and are
inserted into the next below it.
Thus the intercostal muscles decussate, and are
double on the sides of the thorax; but, from the spine
to the angles of the ribs, there are only the external
intercostals, and, from the cartilages to the sternum,
only the internal, and some cellular membrane cover-
ing them. The whole of the internal intercostals, and
the back part of the external, are lined by the pleura.
Use: To elevate the ribs, by causing them to approxi-
mate, and thus to enlarge the cavity of the thorax.
There is a pair of muscles situated on the inner
surface of the sternum, viz:
The Triangularis Sterxi, or Sterno-Costalis, —
Arises, tendinous and fleshy, from the edge of the
whole cartilago ensiformis, and from the edge of the
lower half of the middle bone of the sternum. The
fibres ascend obliquely upwards and outwards, and
form a flat muscle, which is
Inserted, by three or four triangular fleshy and ten-
dinous terminations, into the cartilages of the third,
fourth, fifth, and sixth ribs.
This muscle lies on the inside of the ribs and sternum,
and is lined by the pleura.
Use: To depress the cartilages and the bony
extremities of the ribs, and consequently to assist in
lessening the cavity of the thorax.
CHAPTER XIV.
DISSECTION OF THE MUSCLES
SITUATED ON THE ANTERIOR
PART OF THE NECK, CLOSE
TO THE VERTEBRiE.
Four pair of muscles are here situated.
1. The Longus Colli — Arises, tendinous and
fleshy, from the sides of the bodies of the three supe-
rior dorsal vertebrae, and from the anterior surface of
the transverse processes of the four or five lower
cervical vertebrae.
Inserted, tendinous and fleshy, into the fore part of
the bodies of all the vertebrae of the neck.
This muscle lies behind the oesophagus, and the
great vessels and nerves of the neck.
Use: To bend the neck forwards, and to one side.
2. The Rectus Capitis Internus Major —
Arises, tendinous and fleshy, from the anterior points
of the transverse processes of the third, fourth, fifth,
and sixth cervical vertebrae. It forms a considerable
fleshy belly.
Inserted into the cuneiform process of the os occip-
itis a little before the condyloid process.
This muscle lies before the scaleni, and more
outwardly than the longus colli, over part of which
it passes.
Use: To bend the head forwards.
3. The Rectus Capitis Internus Minor —
Arises, fleshy, from the fore part of the body of the
atlas, near its transverse process; and, ascending
obliquely, is
GUIDE TO ANATOMY. 165
Inserted near the root of the condyloid process of
the occipital bone, under the last described muscle.
Use: to bend the head forwards.
4. The Rectus Capitis Lateralis — Arises,
fleshy, from the anterior and upper part of the
transverse process of the atlas.
Inserted, tendinous and fleshy, into a scabrous ridge
of the os occipitis, which extends from the condyloid
process of that bone towards the mastoid process.
It is situated immediately behind the internal jugular
vein, where it comes out from the cranium.
Use: To pull the head a little to one side.
Besides these muscles, we meet also with
1. The Scalenus Anticus — Arises, by three ten-
dons, from the transverse processes of the fourth, fifth,
and sixth vertebrae of the neck.
Inserted, tendinous and fleshy, into the upper edge
of the first rib, near its cartilage.
2. The Scalenus Medius — Arises, tendinous, from
the transverse processes of all the vertebrae of the
neck.
Inserted into the upper and outer part of the first
rib, from its root to within the distance of half an inch
from the scalenus anticus.
The nerves to the superior extremity pass between
this muscle and the former.
3. The Scalenus Posticus — Arises, tendinous,
from the transverse processes of the fifth and sixth
vertebrae of the neck.
Inserted into the upper edge of the second rib, near
the spine.
These muscles are covered before by the sterno-
mastoideus and trapezius, behind by the trapezius and
levator scapulae; but the scaleni are so connected with
the muscles of the spine, that the whole of them cannot
be demonstrated till the muscles of the back and neck
are dissected.
166 LONDON DISSECTOR, OR
Use of these three muscles: To bend the neck to
one side, and, when the muscles of both sides act, to
bend it forwards; or, when the neck is fixed, to elevate
the ribs, and dilate the chest.
We have given the description of the three parts,
but it is proper to remark that some anatomists of
eminence regard it as one triangular muscle.
CHAPTER XV.
DISSECTION OF THE SUPERIOR
EXTREMITY.
SECTION. I.
OF THE SHOULDER AND ARM.
In the thigh we saw a strong fascia, arising from
the neighbouring bones and ligaments, firmly investing
the muscles, and giving origin to some of their fibres;
but, on removing the integuments of the shoulder and
arm, we meet with no regular fascia. The muscles,
like those on the outside of the thorax, are covered
by condensed cellular substance, which might be taken
for a thin aponeurosis; but which is widely different
in its nature, and ought to be regularly dissected off
with the integuments.
There are ten muscles situated on the shoulder and
the humerus.
1. The Deltoides — Jlrises, tendinous and fleshy,
from the posterior third of the clavicle, from the whole
edge of the acromion, and from the lower margin of
GUIDE TO ANATOMY. 167
the whole spine of the scapula. From these several
origins the fibres run in different directions, and con-
verge. Those arising from the clavicle run outwards
and downwards: those from the spine of the scapula
outwards, forwards, and downwards; and those from
the acromion directly downwards.
Inserted, tendinous, into a triangular rough surface
on the outer side of the os humeri, near its middle.
This muscle is entirely superficial, except where
the thin fibres of the platysma myoides arise from its
anterior surface. It forms a strong coarse muscle, and
covers the whole of the fore part and outside of the
shoulder joint.
Use: To draw the arm directly upwards, and to
move it a little forwards or backwards, according to
the different directions of its fibres. Having reflected
this muscle from the scapula and clavicle, you will
expose more completely the muscles on the dorsum
of the former bone. They fill up the posterior surface
of the scapula, and are covered by a fascia, which
adheres to the spine and edges of that bone. On dis-
secting off this fascia, the fleshy fibres of the muscles
will be found arising from its inner surface.
2. The Supra-Spinatcs — Arises, fleshy, from all
that part of the base of the scapula which is above its
spine; from the superior costa as far forwards as the
semilunar notch; from the spine itself, and from the
concave surface betwixt it and the superior costa.
The fleshy fibres, as they approach the neck of the
scapula, terminate in a tendon which passes under the
acromion, slides over the neck of the scapula (to which
it is connected by loose cellular membrane,) adheres
to the capsular ligament of the shoulder-joint, and is
Inserted into the anterior and superior part of the
great tuberosity near the head of the os humeri.
Use: To raise the arm.
3. The Infra-Spinatds, Arises, principally fleshy,
168 LONDON DISSECTOR, OR
from the lower part of the spine of the scapula
as far back as the triangular flat surface; from the
base of the bone below the spine to near the inferior
angle; from the posterior ridge of the inferior costa;
and from all the dorsum of the bone below the spine.
The fibres ascend and descend towards a middle
tendon, which runs forwards over the neck of the
bone, and adheres to the capsular ligament.
Inserted, by a strong short tendon, into the middle
part of the great tuberosity of the os humeri.
Use: To roll the humerus outwards, to assist in
raising the arm, and in moving it outwards when
raised.
4 The Teres Minor — Arises, fleshy, from the
inferior costa of the scapula, extending from the neck
of the bone to within an inch or two of the inferior
angle. It passes forwards along the inferior edge of
the infra-spinatus, adheres to the capsular ligament of
the shoulder-joint, and is
Inserted, tendinous and fleshy, into the lower and
back part of the great tuberosity of the os humeri.
Use: To draw the humerus downwards and back-
wards, and to roll it outwards.
5. The Teres Major — Arises, from an oblong,
rough, flattened surface, at the inferior angle of the
scapula. It forms a thick belly, which passes for-
wards and upwards towards the inside of the arm.
Inserted, by a broad thin tendon, into the ridge of
the os humeri, at the inner side of the groove for
lodging the tendon of the long head of the biceps
flexor cubiti; its tendon is inserted along with the
tendon of the latissimus dorsi.
Use: To roll the humerus inwards, and to draw it
backwards and downwards.
6. The Subscapulars — Arises, fleshy, from all
the base of the scapula internally; from the superior
and inferior costse; and from the whole internal surface
GUIDE TO ANATOMY. 169
of the bone. It consists of tendinous and fleshy bun-
dles, which converge, slide over the inner surface of
the neck of the scapula, pass in the hollow under the
root of the coracoid process, and adhere to the inner
part of the capsular ligament of the shoulder joint.
Inserted, by a strong tendon, into the less tuberosity
near the head of the os humeri.
The whole of this muscle is concealed by the scapula
and muscles of the shoulder. It lies betwixt that bone
and the serratus magnus.
Use: To roll the os humeri inwards, and to draw it
to the side of the body.
7. The Biceps Flexor Cubiti — Arises by two
heads. The first and outermost, called the Long
Head, arises, by a strong tendon, from a smooth sur-
face in the upper edge of the glenoid cavity of the
scapula. It passes over the head of the os humeri,
within the capsular ligament of the shoulder-joint, and
enters a groove betwixt the two tuberosities of that
bone. It forms a strong fleshy belly. The second
and innermost, called the Short Head, arises, tendi-
nous, from the lower part of the coracoid process of
the scapula, in common with the coraco-brachialis,
and sends otf a fleshy belly.
These two fleshy bellies are at first only connected
by condensed cellular membrane. They form a thick
mass, and, below the middle of the arm, become in-
separably united. They send off a strong tendon,
which is at first broad, but soon becomes rounder, and
passes over the fore part of the elbow-joint. It then
slides over the cartilaginous middle surface of the
tubercle at the upper end of the radius, and is
Inserted into the posterior and internal rough part
of that tubercle; and by a lateral slip of fascia into the
sheath of the fore arm.
The belly of the muscle is immediatelv under the
15
170 LONDON DISSECTOR, OR
integuments, and so is the tendon where it passes over
the elbow-joint.
Use: To turn the hand supine, to bend the fore-arm
on the arm, and the arm on the shoulder.
8. The Coraco Brachialis — Arises, tendinous and
fleshy, from the middle part of the apex of the cora-
coid process of the scapula. Its fibres, as it descends,
also arise from the edge of the short tendon of the bi-
ceps flexor cubiti. It forms a flat fleshy belly which
is always perforated by the nerve, named Musculo-
Cutaneus.
Inserted, tendinous and fleshy, about the middle of
the internal part of the os humeri, into a rough ridge.
Use: To move the arm upwards and forwards.
9. The Brachialis Internus — Arises from the
middle of the os humeri, by two fleshy slips, which
pass on each side of the insertion of the deltoid muscle;
fleshy from all the fore part of the bone below, nearly
as far as the condyles. The fibres converge, pass over
the elbow-joint, and adhere to the capsular ligament.
Inserted, by a strong short tendon, into the rough
surface immediately below the coronoid process of
the ulna.
Use: To bend the fbre-arm.
10. The Triceps Extensor Cubiti is the great
muscle which covers all the back part of the arm. It
arises by three heads. The first, or long head, by a
broad tendon, from the inferior costa of the scapula
near its cervix; this forms a large belly, which covers
the back part of the os humeri. The second, or short
' head, arises, on the outer and back part of the os hu-
meri, from a ridge which runs from the back part of
the great tuberosity towards the outer condyle. The
third head, called Brachialis Externus, arises by
an acute beginning, from the inside of the os humeri
above its middle, and from a ridge extending to the
inner condyle.
GUIDE TO ANATOMY. 171
The three heads uuite above the middle of the os
humeri, and invest the whole back part of the bone.
They form a thick strong tendon, which is
Inserted into the Olecranon, and partly into the
condyles of the os humeri, adhering firmly to the cap-
sular ligament.
The tendon of the triceps sends off a thin fascia,
which covers the triangular surface of the ulna, on
which we commonly lean. Numerous fibres are also
sent off to assist in forming the fascia of the fore-arm.
Use: To extend the fore-arm. The long head will
also assist in drawing the arm backwards.
The Anconeus is a small triangular muscle, situated
at the outer side of the olecranon, immediately under
the integuments.
It arises, tendinous, from the posterior and lower
part of the external condyle of the os humeri; forms a
thick triangular fleshy mass, adhering to the capsular
ligament of the elbow-joint, and is
Inserted into the concave surface on the outside of
the olecranon, and into the posterior edge of the ulna.
This muscle lies betwixt the upper part of the ex-
tensor carpi ulnaris and the olecranon. It is partly
covered by the tendon of the triceps extensor cubiti,
and is enveloped in a fascia sent off from that tendon.
Use: To assist in extending the fore-arm.
SECTION II.
DISSECTION OF THE FASCIA AND MUSCLES SITUATED
ON THE CUBIT OR FORE ARM.*
On removing the integuments of the fore-arm, we
find, as in the leg, a strong fascia investing all the
* In the foUowing description, the palm of the hand is supposed to be
turned forwards, so that the radius and thumb are upon the outer side
of the fore-arm, and the ulna and little finger upon its inner side.
172 LONDON DISSECTOR, OR
muscles. This fascia is continued from the intermus-
cular ligaments which pass down to the condyles of
the os humeri. It is attached to the condyles, and
adheres firmly to the olecranon of the ulna. On the
posterior part, it receives a great addition of fibres
from the tendon of the triceps extensor; and on the
fore-part of the arm, it appears to be a continuation
of the aponeurosis which is sent off from the biceps
flexor cubiti.
Above the fascia, we meet with several cutaneous
veins and nerves.
The dissection of the fascia of the fore-arm is simi-
lar to that of the fascia of the leg. It is found firmly
attached to the fibres of the muscles, so that the ex-
posed surface appears ragged. Between the muscles
it sends down Ligaments called Intermuscular, which
connect the muscles, and give origin to many of their
fibres.
General Observations. — In dissecting the fore-arm,
you will not expect to find each muscle separate from
the contiguous ones, as far as its very origin from the
bones. The partitions of fascia unite them most firmly
to a considerable distance from their commencement;
and these connections should not be disturbed, since
they are as justly to be regarded in the light of origins
of the muscles, as the attachments which the fibres
have to the bone. The muscles are divided into two
masses; of which one lies over the radius and back of
the fore-arm, and contains the supinators and exten-
sors: the other, situated over the ulna, and inner side
of the fore-arm, consists of the pronators and flexors.
Although some muscles in each of these masses arise
quite separately, others are joined into a common ten-
dinous and fleshy origin, in the manner just described.
First then, clean all the muscles as they lie; and after
observing them in their relative position, reflect each
muscle, beginning with the superficial ones, and read
its description at the same time.
GUIDE TO ANATOMY. 17-3
The student may perhaps remember the muscles
more readily, by arranging them in classes of three
each; thus:
For the motion of the wrist, three flexors, the ulnari?,
radialis, and medius, commonly called palmaris lon-
gus. Three extensors, ulnaris, radialis longior, and
brevior. Three pronators, the teres, quadratus, and
the mass of flexor muscles. Three supinators, the
supinator longus, brevis, and biceps cubiti. There
are three extensors of the fingers, extensor communis
digitorum, extensor primi digiti, extensor minimi
digiti. Three extensors of the thumb, extensor primus,
secundus, and tertius. Three flexors of the fingers and
thumb, flexor digitorum sublimis, flexor digitorum pro-
fundus, flexor pollicis longus.
MUSCLES SITUATED ON THE FORE PART OF THE
CUBIT, AND ARISING FROM THE INNER CON-
DYLE OF THE OS HUMERI.
These are eight in number, and may be divided
into two classes: the superficial, and the deep-seated.
First, the superficial.
All the muscles passing from the inner condyle
may be said to arise by one common tendinous head;
but they will be here described as arising distinct
from the condyle. It must, however, be recollected,
that their origins are intimately connected by inter-
muscular ligaments, and that they cannot be separated
without dividing some of their fibres.
1. The Pronator Radii Teres — Arises, tendi-
nous and fleshy, from the anterior surface of the inner
condyle of the os humeri, and from the coronoid pro-
cess of the ulna, and the fascia of the fore arm. The
fibres pass outwards, run by the side of the tubercle
of the radius, and pass over the outer edge of that
bone, to be
15*
174 LONDON DISSECTOR, OR
Inserted, tendinous and fleshy, into a rough surface
on the back part of the radius about its middle.
Its tendon, to arrive at its place of insertion, passes
under the belly of the supinator longus, and, when
that muscle is removed, will be found inserted into
the radius immediately below the supinator brevis.
Use: To roll the radius, together with the hand,
inwards.
2. The Flexor Carpi Radialis — Arises, from
the lower and fore part of the internal condyle of the
os humeri; fleshy from the fascia and intermuscular
ligaments, and from the upper end of the ulna. It
forms a thick belly, which runs down the fore arm,
and terminates in a flat tendon. This tendon passes
under the annular ligament* of the wrist, runs through
a groove in the os trapezium, and is
Inserted into the fore part of the base of the meta-
carpal bone sustaining the fore finger.
Its insertion cannot be seen till the palm of the hand
is dissected, where it will be found concealed by the
muscles of the ball of the thumb.
Use: To bend the hand, and to assist in its prona-
tion.
3. The Palmaris Longus — Arises, by a slender
tendon, from the fore part of the inner condyle of the
os humeri; and fleshy, from the intermuscular liga-
ments; it forms a short fleshy belly, which soon sends
off a long slender tendon. This tendon descends along
the fore arm, and is
* The annular ligament of the wrist "consists of two parts. 1. The
ligamentum carpi transTersale externum passes from the styloid process
of the ulna and os pisiforme, transversely, over the back of the wrist,
and spreads out broad, to be affixed to the styloid process of the radius.
Under it pass the tendons of the extensor muscles. 2. The ligamentum
carpi transversale internum is a strong ligament, which passes across the
fore part of the wrist. It arises from the os pisiforme and os unciforme
on the inner edge of the wrist, and is attached to the os scaphoides and
os trapezium on the outer edge. Under it pass the tendons of the flexor
muscles.
GUIDE TO ANATOMY. 175
Inserted, near the root of the thumb, into the annular
lisrament of the wrist, and into a tendinous mem-
brane that covers the palm of the hand, named Fascia,
or Aponeurosis Palmaris.
It arises betwixt the flexor carpi radialis and flexor
ulnaris. Its tendon descends between these two
muscles, and above the fibres of the flexor digitorum
sublimis. This muscle is sometimes wanting.
Use: To bend the hand, and to stretch the palmar
aponeurosis.
4. The Flexor Carpi Ulnaris — Arises, from the
inferior part of the internal condyle of the os humeri;
tendinous and fleshy, from the inner side of the olec-
ranon, and by a tendinous expansion from the posterior
ridge* of the ulna, to nearly the lower end of the bone;
and from the intermuscular ligaments and fascia of
the fore-arm. The fibres pass obliquely forwards
into a tendon which runs over the fore-part of the
ulna, and is
Inserted into the os pisiforme, and sometimes sends
its fibres over a small ligament which goes to the base
of the metacarpal bone of the little finger.
The tendon is bound down by a thin aponeurotic
slip, which passes from the inner part of the annular
ligament of the wrist.
Use: To bend the hand.
5. The Flexor Sublimis Perforatus — Arises,
tendinous and fleshy; from the under part of the inter-
nal condyle of the os humeri; tendinous, from the
lower part of the coronoid process of the ulna; fleshy,
from the tubercle of the radius, from the middle of
the fore part of that bone, and from the middle third
of its outer edge. These origins form a strong fleshy
mass, which sends off four tendons. The tendons are
connected by cellular membrane, and pass together
* The ridge which leads to the styloid process.
176 LONDON DISSECTOR, OR
under the annular ligament of the wrist; after which
they separate, become thinner and flatter, pass along
the metacarpal hone and first phalanx of each of the
fingers, and are
Inserted into the anterior and upper part of the
second phalanx, each tendon being, near the extrem-
ity of the first phalanx, divided for the passage of a
tendon of the flexor profundus.
To expose the origin of this muscle, the bellies of
the pronator teres, flexor carpi radialis, and palmaris
longus, must be detached from the condyle.
Its tendons will be seen in the dissection of the
palm of the hand.
Use: To bend the second joint or phalanx of the
fingers.
By removing the belly of the flexor sublimis, we
expose the deep seated muscles.
6. The Flexor Profundus Perforans — Arises,
fleshy, from the smooth concavity on the inside of the
ulna, between the coronoid process and the olecranon;
from the smooth flat surface of the ulna, betwixt its
posterior and internal angles; from the under part of
the coronoid process; from the fore part of the ulna
below that process, and from the inner half of the in-
terosseous ligament. This muscle forms a thick mass,
which descends along the fore part of the ulna, ad-
hering to that bone as low as one-third of its length
from its inferior extremity, and terminates in sending
off four tendons. These tendons are flat, pass together
under the annular ligament of the wrist, run through
the slits in the tendons of the flexor sublimis, and are
Inserted into the fore and upper part of the third or
last phalanx of all the fingers.
' Use: To bend the last joint of the fingers.
7. Flexor Longus Pollicis Manus — Arises,
from the upper and fore part of the radius, immedi-
ately below its tubercle, fleshy, from the outer edge
GUIDE TO ANATOMY. 1*7
and anterior surface of that bone as low as two inches
above its inferior extremity, and from the outer part
of the interosseous ligament. It has also generally a
tendinous origin from the internal condyle of the os
humeri. The tendon of the muscle passes under the
annular ligament of the wrist, and is
Inserted into the last bone of the thumb.
Use: To bend the last joint of the thumb.
On separating the lower part of the two last de-
scribed muscles, we expose a small square muscle,
passing transversely just above the wrist, and lying
close to the bones.
8. The Pronator Quadratus — Arises, broad,
tendinous, and fleshy, from the inner edge of the ulna,
extending from the lower extremity of the bone two
inches up its edge. The fibres run transversely,
adhere to the interosseous ligament, and are
Inserted into the lower and anterior part of the
radius.
Use: To turn the radius, together with the hand,
inwards.
MUSCLES SITUATED OX THE OUTER AND BACK PART OF
THE FORE-ARM, AND ARISING FROM THE
OUTER CONDYLE OF THE OS HUMERI.
These muscles are eleven in number, and may be
divided into two classes: the superficial, and the
deep seated.
THE SUPERFICIAL.
The muscles which arise from the outer condyle
are much more distinct in their origins than those from
the inner. Several of them arise a considerable way
up the os humeri; but there is here also a common
tendinous origin, from which the extensor carpi radia-
lis brevior, extensor digitorum communis, and exten-
178 LONDON DISSECTOR, OR
sor carpi radialis, proceed; so that these muscles are
intimately connected.
1. Supinator Radii Longus — Arises, tendinous
and fleshy, from the external ridge of the os humeri,
nearly as far up as the middle of the bone, and ceases
to adhere about two inches above the condyle. It
forms a thick fleshy belly, which passes over the side
of the elbow-joint, becomes smaller, and terminates
above the middle of the fore-arm in a flat tendon.
The tendon becomes gradually rounder, and is
Inserted into the lower end of the radius on its
outer side.
This muscle is situated immediately under the
integuments along the outer edge of the arm and fore-
arm; and its insertion is crossed by the extensors of
the thumb.
Use: To roll the radius outwards, and turn the
palm of the hand upwards; also to bend the fore-arm
on the humerus.
2. The Extensor Carpi Radialis Longior —
Arises, tendinous and fleshy, from the external ridge
of the os humeri, beginning immediately below the
origin of the supinator longus, and continuing to arise
as far as the upper part of the outer condyle. It
forms a thick short belly, which passes over the side
of the elbow-joint, and terminates above the middle
of the radius in a flat tendon. This tendon runs
along the radius, and, becoming rounder, passes
through a groove in the back part of the inferior
extremity of that bone, to be
Inserted into the posterior and upper part of the
metacarpal bone of the fore-finger.
Use: To extend the wrist, and move the hand
backwards, and to assist in bending the fore arm.
3. The Extensor Carpi Radialis Brevior —
Arises, tendinous, from the under and back part of
the external condyle of the os humeri, and from the
GUIDE TO ANATOMY. 179
external lateral ligament of the elbow-joint. Its thick
belly runs along the outside of the radius, and termi-
nates in a tendon, which passes through the same
groove in the radius as the extensor radialis longior,
and under the annular ligament.
Inserted, by a round tendon, into the upper and
back part of the metacarpal bone that supports the
middle finger.
Use: To extend the hand.
4. The Extensor Dig itorum Communis —Arises,
tendinous, from the under part of the external con-
dyle of the os humeri; fleshy, from the n'ermuscular
ligaments which connect it to the extensor carpi
radialis brevior before, and the extensor carpi ulnaris
behind, and from the inner surfVce of the fascia. It
descends along the back pert of the fore-arm, and
adheres to the ulna where it passes over it The
fleshy belly terminates in lour flat tendons, which
pass under the annular ligament in a depression on the
back part of the radius, and are
Inserted into the posterior part of all the bones of
the fingers by a tendinous expansion.
The tendons are connected on the back of the
metacarpal bone by cross slips. The inner part of
this muscle is sometimes described as a separate
muscle, and is called Extensor Proprius Minimi Digiti,
vel Auricularis. It passes through a separate depres-
sion of the radius, and a particular ring of the annu-
lar ligament.
Use: To extend all the joints of the fingers.
The posterior surface of each finger is covered with
a tendinous expansion which is formed by the tendons
of the common extensor, of the lumbricales, and
interossei. This tendinous expansion terminates in
the third or extreme phalanx.
5. The Extensor Carpi Ulnaris — Jlrises, tendi-
nous, from the under part of the external condyle;
180 LONDON DISSECTOR, OR
fleshy, from the intermuscular ligaments and inside of
the fascia. It crosses towards the ulna, and arises,
fleshy, from the back part of that bone. It termi-
nates in a strong tendon, which passes through a
groove in the back part of the lower end of the ulna,
under the annular ligament, and is
Inserted into the posterior and upper part of the
metacarpal bone of the little finger.
This muscle is entirely superficial, and serves to
extend the wrist, and bring the hand backwards; but
chiefly to bend the hand laterally towards the ulna.
The next muscle^vould be the anconeus, but that has
been already described.
By removing the superficial muscles, we expose
THE DEEP SEATED.
6. The Supinator Radii Brevis — Arises, tendi-
nous, from the lower part of the external condyle of
the os humeri; from the outer surface of the ulna; and
from the interosseous ligament: it passes outwards
round the upper part of the radius, and is
Inserted into the upper and outer edge of the tuber-
cle of the radius, and into an oblique ridge extending
from the tubercle downwards and outwards to the
insertion of the pronator teres.
This muscle nearly surrounds the upper and outer
part of the radius.
Use: To roll the radius outwards, and bring the
hand supine.
On the back part of the fore arm we meet with
three muscles going to the thumb, and one to the fore
finger.
7. The Extensor Ossis Metacarpi Pollicis —
Arises, fleshy, from the middle and posterior part of
the ulna, immediately below the termination of the
anconeus, from the interosseous ligament, and from
GUIDE TO ANATOMY. 181
the posterior surface of the radius below the insertion
of the supinator radii brevis. The fleshy fibres ter-
minate in a tendon which passes through a groove in
the outer edge of the lower extremity of the radius:
Inserted, generally by two tendons, into the os tra-
pezium, and into the upper and back part of the meta-
carpal bone of the thumb.
Use: To extend the metacarpal bone of the thumb
outwardly.
8. The Extensor Primi Internodii Pollicis
Manus — Arises, fleshy, from the back part of the
ulna below its middle, from the interosseous ligament
and radius. It runs along the lower edge of the ex-
tensor ossis metacarpi, and forms a tendon, which
passes through the same groove as the tendon of that
muscle, and is
Inserted into the posterior part of the first bone of
the thumb. Part of the tendon is also continued into
the base of the second or extreme phalanx.
Use: To extend the first phalanx of the thumb
obliquely outwards.
It is called also Extensor secundi internodii.
9. The Extensor Secundi Internodii Polli-
cis Manus — Arises, tendinous and fleshy, from the
posterior surface of the ulna above its middle, and
from the interosseous ligament. Its belly partly
covers the origins of the two other extensors of the
thumb, and terminates in a tendon, which runs through
a distinct groove in the back part of the radius, and is
Inserted into the posterior and upper part of the
second or extreme phalanx of the thumb.
Use: To extend the last joint of the thumb obliquely
backwards.
It is called also Extensor tertii internodii.
10. The Indicator, or Extensor Primi Digiti —
Arises, by an acute fleshy beginning, from the middle
16
182 LONDON DISSECTOR, OR
of the back part of the ulna, and from the interosseous
ligament. Its tendon passes through the same sheath
of the annular ligament with the extensor digitorum
communis, and is
Inserted into the posterior part of the fore finger
with the tendon of the common extensor.
Use: To assist in extending the fore finger.
SECTI ON III.
DISSECTION OF THE PALM OF THE HAND.
The tendons which pass over the bones of the car-
pus into the palm of the hand are firmly bound down
by the annular ligament of the wrist. They are in-
vested and connected by cellular membrane, which
forms sheaths, and secretes synovia to facilitate their
motions.
In the sole of the foot we saw a strong fascia sup-
porting and covering the muscles, and passing from
the heel to the toes. On removing the integuments
from the palm of the hand, we meet with a similar
fascia. It arises from the tendon of the palmaris longus,
and from the annular ligament of the wrist, expands
over all the palm of the hand, and is fixed to the roots
of the fingers, splitting, to transmit their tendons. This
is the Fascia or Aponeurosis Palmaris. It is triangular.
Where it arises from the wrist, it is narrow, and does
not cover the bases of the metacarpal bones of the little
and fore-finger. As it runs over the hand, it becomes
broader, and is fixed by a bifurcated extremity in the
lower end of each of the metacarpal bones of the four
fingers. The palmar fascia is strong and thick, con-
GUIDE TO ANATOMY. 183
ceals and supports the muscles of the hand, and may
he distinguished into four portions, which are con-
nected by transverse fibres, while other fibres pass
from them downwards, adhere strongly to the edges
of the metacarpal bones, and separate the tendons of
each finger.
There is a small thin cutaneous muscle situated
between the wrist and the little finger.
The Palmaris Brevis — Arises from the annular
ligament of the wrist, and from the inner edge of the
fascia palmaris.
Inserted, by small scattered fibres, into the skin and
fat which covers the short muscles of the little finger
and inner edge of the hand.
Use: To assist in contracting the palm of the hand.
The fascia palmaris may now be removed. Under
it will be seen the four tendons of the flexor sublimis
perforatus. They are seen coming from beneath the
annular ligament of the wrist, and diverging as they
pass towards their respective fingers. Each tendon
splits at the extremity of the first phalanx, for the
passage of the tendon of the flexor profundus perfo-
ratus, and is inserted into the base of the second
phalanx.
Under the flexor sublimis are the four tendons of the
flexor profundus perforans,which pass through the slits
in the tendons of the former, and are inserted into the
bases of the third phalanges of the fingers.
The Lumbricales are four small muscles, which
arise, from the outer side of the tendons of the flexor
profundus perforans. The tendon of each muscle
runs along the outer edge of the finger, and is
Inserted into the tendinous expansion which covers
the back part of the phalanges of the fingers, about
the middle of the first joint.
Use: To bend the first phalanges of the fingers, the
184 LONDON DISSECTOR, OR
flexor profundus being previously in action, to afford
them a fixed point.
The short muscles of the thumb and fore-finger are
five in number.
1. The Abductor Pollicis Manus — Arises, from
the anterior surface of the annular ligament of the wrist,
and the os naviculare and os trapezium.
Inserted, into the root of the second bone of the
thumb, and the tendinous membrane covering the back
part of all the phalanges.
This muscle is situated immediately under the
integuments, and is the outermost portion of the mus-
cular mass forming the ball of the thumb.
Use: To draw the thumb from the fingers.
2. The Flexor Ossis Metacarpi Pollicis, or
Opponens Pollicis — Arises, under the last, from the
annular ligament of the wrist, and the os naviculare
and os trapezium.
Inserted, into the anterior and lower part of the
metacarpal bone of the thumb.
Use: To bring the first bone of the thumb inwards.
3. The Flexor Brevis Pollicis Manus arises by
two distinct heads, (formed by the tendon of the long
flexor,) from the inside of the annular ligament; from
the anterior surface of the os trapezium and os trape-
zoides; from the root of the metacarpal bone of the
fore finger; and from the upper part of the os magnum
and os unciforme.
Inserted into the sesamoid bones, and the first pha-
lanx of the thumb.
This muscle is in great part concealed by the
abductor pollicis.
Use: To bend the first joint of the thumb.
4. The Adductor Pollicis Manus — Arises,
fleshy, from almost the whole length of the metacar-
pal bone of the middle finger.
GUIDE TO ANATOMY. 185
Inserted, into the first phalanx of the thumb, at its
carpal extremity.
Use: To pull the thumb towards the fingers.
5. The Abductor Indicis Manus — Arises, from
the os trapezium, and the metacarpal bone of the
thumb, and is
Inserted, into the first phalanx of the fore finger.
This muscle is seen most distinctly on the back of
the hand. It is there superficial, and is crossed by
the tendon of the extensor secundi internodii pollicis.
In the palm of the hand it is concealed by the muscles
of the ball of the thumb.
To move the fore finger towards the thumb,
or the thumb towards the fore finger.
The insertion of the flexor carpi radialis is exposed
by removing the muscles of the thumb.
The short muscles of the little finger are three in
number.
1. The Abductor Minimi Digiti Manus —
Arises, from the os pisiforme, and adjacent part of the
annular ligament of the wrist.
Inserted, into the side of the first phalanx, and the
tendinous expansion which covers the back part of
the little finger.
Use: To draw the little finger from the rest.
2. The Flexor Parvus Mimmi Digiti — Arises,
fleshy, from the outer side of the os unciforme, and
from the annular ligament of the wrist, where it is
affixed to that bone.
Inserted, by a roundish tendon, into the base of the
first phalanx of the little finger.
Use: To bend the little finger, and bring it towards
the other fingers.
3. Adductor Metacarpi Minimi Digiti Manus,
Arises, from the os unciforme, and adjacent part of the
annular ligament of the wrist
16*
186 LONDON DISSECTOR, OR
Inserted, into the fore part of the metacarpal bone
of the little finger, nearly its whole length.
It is concealed by the bellies of the abductor and
flexor brevis minimi digiti.
Use: To bend and bring the metacarpal bone of the
little finger towards the rest.
The Interossei are small muscles situated between
the metacarpal bones, and extending from the bones
of the carpus to the fingers. They are exposed by
removing the other muscles of the thumb and fingers.
The Interossei Interni are seen in the palm of
the hand, and are four in number. They arise, tendi-
nous and fleshy, from the base and sides of the meta-
carpal bones, and are inserted into the side of the first
phalanx of the fingers, and into the tendinous expansion
which covers the posterior surface of all the phalanges.
1. The First, named Prior Indicis, arises from the
outer part of the metacarpal bone of the fore-finger;
and is inserted into the outer side of the first phalanx
of that finger.
Use: To draw the fore-finger towards the thumb.
2. The Second, named Posterior Indicis, arises
from the root and inner side of the metacarpal bone
of the fore-finger; and is inserted into the inner side of
the first phalanx of the fore-finger.
Use: To draw that finger outwards.
3. The Third, named Prior Annularis, arises from
the root and outer side of the metacarpal bone of the
ring-finger; and is inserted into the outer side of the
first phalanx of the same finger.
Use: To pull the ring-finger towards the thumb.
4. The Fourth, named Interosseus Auricularis,
arises from the root and outer side of the metacarpal
bone of the little finger; and is inserted into the outer
side of the first phalanx of the little finger.
Use: To draw the little finger outwards.
GUIDE TO ANATOMY. 187
The internal interossei also assist in extending the
fingers obliquely.
The Interossei Externi, seu Bicipites, are three
in number. They are larger than the internal, and
are situated between the metacarpal bones on the back
of the hand. Each of these muscles arises by a double
head, from two metacarpal bones, and is inserted into
the side of one of the fingers, and into the tendi-
nous expansion which covers the posterior part of
the phalanges.
1. The First, named Prior Medii, arises from the
roots of the metacarpal bones of the fore and middle
fingers; and is inserted into the outer side of the mid-
dle finger.
Use: To draw the middle finger towards the thumb.
2. The Second, named Posterior Medii, arises from
the roots of the metacarpal bones of the middle and
ring fingers; and is inserted into the inner side of the
middle finger.
Use: To draw the middle finger towards the ring-
finger.
3. The Third, named Posterior Annularis, arises
from the roots of the metacarpal bones of the ring and
little fingers; and is inserted into the inner side of the
ring-finger.
Use: To draw the ring-finger inwards. The ex-
ternal interossei also extend the fingers.
-
PART II
DISSECTION OF THE VASCULAR
AND NERVOUS SYSTEMS.
We will suppose that the subject has been injected;
and that the student proceeds to the examination of the
lower extremity. He may proceed according to the
rules laid down for the dissection of the abdominal
muscles, and having carefully raised the external ob-
lique he will meet in the region of the abdominal ring
the epigastric artery, and the circumflexa ilii, branches
of the external iliac artery.
The Epigastric Artery comes off from the inside of
the external iliac, crosses the external iliac vein,
passes obliquely upwards and inwards, under Pou-
part's ligament, to which it is but loosely connected,
and runs behind the upper extremity of the abdomi-
nal ring and spermatic chord, to reach the rectus ab-
dominis. At first it is situated between the posterior
surface of that muscle and the peritoneum, but higher
up between the muscular fibres and the sheath. It
terminates in ramifications, which supply the rectus,
and which inosculate with those of the mammaria
interna, sent down from the thorax on each side of the
sternum.
The circumflexa Mi is sent off from the outside of
the external iliac, passes upwards and outwards, runs
along the inside of Poupart's ligament, till it arrives
at the anterior superior spinous process of the os
ilium; thence it is continued along the inside of the
190 LONDON DISSECTOR, OR
spine of the ilium, lying close upon the bone between
the transversalis abdominis and the upper edge of the
iliacus internus, to both of which it gives twigs, and
ends in inosculating with the ileo-lumbar artery. The
muscles of the abdomen may now be removed; and
having cut through the peritoneum, the student will
meet with the abdominal aorta and its various branches.
OF THE VESSELS AND NERVES SITUATED
BEHIND THE PERITONEUM.
1. THE ARTERIES, viz: THE AORTA ABDOMINALIS,
AND ITS BRANCHES.
The Aorta passes from the thorax into the abdo-
men, between the crura of the diaphragm, close upon
the spine. It then descends on the fore part of the
vertebrae, lying not exactly in the middle, but rather
inclined to the left side. On the fourth lumbar ver-
tebra, it bifurcates into the two primitive or common
iliac arteries.
BRANCHES OF THE ABDOMINAL AORTA.
1. The two Phrenic Arteries arise from the Aorta,
before it has fairly entered into the abdomen, and
ramify over the diaphragm; — sometimes they come off
in one trunk, which bifurcates; sometimes one of
them arises from the coeliac.
2. The Cosliac Artery comes off at the point where
the aorta has fairly extricated itself from the dia-
phragm; it is a single, large, but short trunk, situated
between the inferior surface of the liver, and the small
curvature of the stomach, and surrounded by the
meshes of the semilunar ganglion. It divides at once
GUIDE TO ANATOMY. 191
into three branches; and as they depart in different
directions from one point, as from a centre, the trunk
is called the Axis Artert.e Cgeliace.
(1.) A. Coronaria Ventriculi, the middle branch,
is the smallest of the three; it passes from the axis
towards the left side, and arriving at the cardiac
orifice of the stomach, where it attaches itself to that
organ, sends a branch round the cardia, named Ramus
Coronaria Dexter. The trunk itself is then continued
along the lesser curvature from left to right, to inos-
culate with the pylorica or coronaria dextra: it sends
off branches to the little epiploon, &c. It sometimes
terminates in the liver, entering at the portae, and
then it is the largest of the branches of the cceliac.
In this case, the trunk, after ascending towards the
left to reach the cardia, is reflected to the right, in
its way to the liver, and, at the point of reflection,
gives off the coron. venlric.
(2.) Arteria Splenica, leaving the trunk of the
coeliac, goes directly to the side, passes under the
stomach, and along the upper border of the pancreas,
running in a tortuous and serpentine course: it enters
the left concave surface of the spleen in several
branches, but before doing so, it gives off the follow-
ing branches:
a, Pancreatice Parvje to the pancreas, where
it runs along the border of that viscus.
6, Vasa Breyia to the bulging extremity of the
stomach.
c, A. Gastro-epiploica Sinistra, which runs
along the greater curvature of the stomach, inosculat-
ing with the gastro-epiploica dextra.
(3.) Arteria Hepatica runs in a direction oppo-
site to the splenic, towards the right side; but not more
than half of its blood goes to the liver It sends off
the following branches:
a, Pylorica, or Coronaria Dextra, sometimes
192 LONDON DISSECTOR, OR
comes off from the trunk of the hepatic, sometimes
from one of its branches: — reaching the pyloric end
of the stomach, it sends its ramifications along the
lesser curvature, to inosculate with the proper coro-
nary artery.
6, Gastroepiploic a Dextra, or Gastro-duo-
denalis, passes under the pylorus, to reach the great
curvature of the stomach, along which it runs, inoscu-
lating with the gastro-epiploica sinistra, and sending
branches upwards to the stomach, and downwards to
the omentum; it also supplies the upper part of the
duodenum, and sends off a considerable branch to the
right extremity of the pancreas.
The hepatic artery then divides into the right and
left hepatic. The Right is distributed to the right
lobe of the liver, and to the gall-bladder. The Left
supplies the whole of the left lobe, the lobulus Spigelii,
and part of the right lobe of the liver.
3. The Superior Mesenteric Artery is a single
trunk; it leaves the aorta about half an inch lower than
the cceliac artery, it comes out from under the mesoco-
lon, and stretches over the duodenum: it enters the fold
of peritoneum forming the mesentery, and runs down
in this, gradually incurvating from the left to the right
side.
From the right side or concavity of this arch, three
branches are given to the colon.
(1.) A. Ileo-Colica runs down to the caput coli
and last turns of the ileon; its branches upon the
small intestines inosculate with those branches of the
superior mesenteric distributed to the small intestines
in general; and on the great intestine, it inosculates
with the next branch.
(2.) A. Colica Dextra. — This artery runs from
the root of the superior mesenteric artery, across
towards the right side of the colon, where that intes-
tine begins to rise over the kidney.
GUIDE TO ANATOMY. 193
(3.) A. Colica Media. — This branch goes directly
upwards from the trunk of the superior mesenteric,
as it comes out from under the mesocolon. After
running a little way upon the mesocolon, it divides;
and the division going towards the right side, makes
a large inosculation with the colica dextra, while the
left branch makes an opposite sweep, and joins the
colica sinistra, which is a branch of the inferior
mesenteric.
Often there are only two branches instead of these
three; viz. ileo-colica, and colica dextra; then the c.
media is a branch of the latter. Frequently too, there
is only one branch, called colica dextra, and dividing
after its origin, into the three above named.
The left side or convexity of the arch of the supe-
rior mesenteric sends off from sixteen to twenty
branches, which, after forming frequent anastomoses
and arches, proceed to the small intestines.
4. The Renal or Emulgent Arteries are two
in number. Each artery arising, below the superior
mesenteric, from the side of the aorta, passes to the
kidney, and after having given twigs to the renal cap-
sule, and adipose membrane, enters the smaller arch
of the kidney. The right artery is longer than the
left, and passes behind the vena cava ascendens.
5. The Spermatic Arteries are also two; they
come off about an inch below the emulgent from the
fore part of the aorta. Each artery descends behind
the peritoneum, giving twigs to the parts in its course,
and accompanied by the spermatic vein and nerves.
It then passes through the abdominal ring, and enters
the upper part of the testicle in five or six branches.
In the female it supplies the ovaria and fundus uteri.
6. The Inferior Mesenteric is a single trunk,
which comes off rather from the left side of tiie aorta,
below the spermatic arteries; it passes in the mesentery
194 LONDON DISSECTOR, OR
to the left side of the abdomen, where it divides as
follows:
(1 .) The Colica Sinistra, an artery which ascends
along the left side of the colon, to inosculate with the
A. Colica Media.
(2.) Branches which pass to the sigmoid flexure.
(3.) The great trunk of the artery runs down behind
the rectum, on which it ramifies largely, and is termed
Art. Hemorrhoidalis Interna.
7. The Lumbar Arteries are five or six small
arteries on each side, which arise from the back part
of the aorta, and are distributed to the spinal canal,
peritoneum, muscles of the spine, and of the sides of
the abdomen and pelvis. They inosculate with the A.
Epigastrica, Circumflexa ilii &c.
8. A. Sacra Media is a single artery, arises from
the back part of the aorta at its bifurcation, and
descends along the anterior surface of the sacrum,
giving twigs to all the neighboring parts.
At the fourth lumbar vertebra, the aorta bifurcates
into the two primitive or common iliacs.
The Iliaca Communis runs along the edge of the
psoas muscle, and at an inch or two from its origin
divides into,
(1.) The Internal Iliac, which passes down into the
pelvis.
(2.) The External Iliac, which, following the direc-
tion of the psoas muscle, passes under Poupart's liga-
ment, and becomes the inguinal artery.
2. VEINS.
The Vena Cava Abdominalis, vel Inferior, is
formed by the junction of the two common iliac veins;
it passes up through the abdomen on the lumbar ver-
tebra, and on the right side of the aorta.
GUIDE TO ANATOMY. 195
In this course it receives the following veins, which
resemble their corresponding arteries.
1 . The Lumbar Veins.
2. The Emulgent or Renal Veins; — the left is the
longer, as it crosses over the fore part of the aorta.
3. The Right Spermatic Vein; — the left enters the
left renal vein.
The vena cava then passes through the fissure of
the liver, being nearly surrounded by that viscus, and
receiving three branches from it, called the \ en.e
Hepatice. It then perforates the diaphragm, and
enters the thorax.
The common iliac vein of each side is formed by the
union of two branches, the External and Internal
Iliac Veins, which accompany the arteries of the
same name: — The common iliac vein of each side lies
on the inside of its artery; hence both veins cross be-
hind the right iliac artery, to unite and form the vena
cava, on the fore part of the lumbar vertebras.*
do not join the cava, but
are united behind the
pancreas, to form the
Vena Portae. This vein
ramifies anew through
the liver, and its blood
is returned into the vena
cava by the venae cava?
t hepaticae.
Although the trunks just enumerated are the chief
veins that contribute to form the vena portae, yet the
returning veins of all the viscera enclosed in the peri-
toneum, except the liver, are included in the same
system, and join one or other of the large trunks. This
is the case with the stomach, pancreas, gall-bladder,
* It may be here proper to observe, that generally a great vein accom-
panies every great artery; but when the ramifications become small,
each artery is attended by two veins.
The Superior Mes-
enteric Vein, the In-
ferior Mesenteric
Vein, and the Splenic
Vein,
196 LONDON DISSECTOR, OR
and omentum. The blood which goes to the spleen,
large and small intestines, is all returned by the three
great trunks.
3. NERVES.
1 . The eighth pair, or Par Vagum, descending on
each side of the oesophagus through the diaphragm,
forms the two Stomachic Plexuses on the anterior
and posterior surfaces of the stomach. These plexuses
send some branches to the cceliac, to the hepatic, and
to the splenic plexus.
2. The Splanchnic Nerve, or Anterior Intercos-
tal, a branch sent off by the intercostal nerve in the
thorax, enters the abdomen betwixt the crura of the
diaphragm; here each nerve forms a Semilunar
Ganglion by the side of the cceliac artery.
From this ganglion, on each side, branches are sent
across, which communicate intimately together, and
form round the root of the cosliac artery, a very inti-
mate plexus, containing several ganglia of various
sizes, formerly called the Solar, but now more cor-
rectly the Cceliac Plexus. Nerves pass from this
plexus, with the branches of the aorta, to the various
viscera of the abdomen: in a common dissection these
nerves cannot be clearly demonstrated, as they lie very
close on the respective arteries, and are surrounded
by much condensed cellular substance; they form the
hepatic, splenic, superior, and inferior mesenteric,
renal, and spermatic plexuses.
3. The trunk of the intercostal nerve, the posterior
intercostal, perforates the small muscle of the dia-
phragm close to the spine, runs down on the sides of
the lumbar vertebrae, and along the upper edge of the
psoas magnus. It terminates on the extremity of the
os coccygis, by union with the nerve of the opposite
side, in a ganglion named Ganglion Impar. In this
GUIDE TO A> ATOMY. 197
course, it communicates with the lumbar nerves, and
the various abdominal plexuses.
The Thoracic Duct may be seen passing from
the abdomen into the thorax, between the aorta and
the right crus of the diaphragm. It is larger here
than in its subsequent course, and the dilated portion
is called receptaculum chyli, as the lacteals pour in the
chyle in this situation.
OF THE VESSELS AND NERVES CONTAINED
WITHIN THE PELVIS.
1. ARTERIES.
The A. Iliaca Interna, having left the trunk of
the iliaca communis, passes immediately into the pel-
vis, where it gives off several large arteries.
1. A. Ileo-Lumbalis supplies the psoas and iliacus
internus muscles. *
2. A. Sacrs: Laterales, two or three small ves-
sels which supply the sacrum, cauda equina, and
neighboring parts.
3. A. Glutea (or iliaca posterior,) a very large
branch, passes out of the pelvis through the upper
part of the sciatic notch to supply the haunch, but, in
its passage, it gives some branches to the os sacrum,
os coccygis, the rectum, and the muscles situated
within the pelvis.
4. A. Sciatica passes out of the pelvis by the
sciatic notch, and below the pyriformis muscle to
supply the hip: in its passage it gives branches to the
neighboring parts.
5. A. Pudica (pudenda communis or interna) is the
branch of the internal iliac, which is more immediately
destined to supply the parts of generation, perineum,
and lower part of the rectum: it goes out of the pelvis
17*
198 LONDON DISSECTOR, OB
above the superior sacro-sciatic ligament, twists round
it, and re-enters the pelvis above and before the infe-
rior sacro-sciatic ligament; it then descends on the
inside of the tuber ischii, ascends on the inner surface
of the rami of the ischium and pubis, and, reaching
the root of the penis, divides into two branches.
(1.) A. Perinei, a branch which, after giving
twigs to the bulb of the urethra and neighboring
muscles, enters the crus of the penis, and subdivides
into branched which pass to both extremities of the
crus.
(2.) A. Dorsalis Penis, passes under the arch of
the pubis, runs along the dorsum penis, and is distri-
buted to the integuments.
In its course the pudic artery gives off many
branches.
(1.) While in the pelvis, it gives twigs to the blad-
der, prostate gland, and rectum.
(2.) A. H/emorrhoidales Externa come from
the putlic while passing by the anus.
(3.) A. Transversa Perinei, following the course
of the transversus perinei muscle.
(6.) A. Obturatrix descends on the inside of the
psoas muscle, passes through the foramen in the ob-
turator ligament to the muscles on the inside of the
thigh.
(7.) A. Hypogastrica, which in the fetus sends
off the umbilical artery, is in the adult continued only
to the side of the bladder, to which it gives branches;
in the female, it enters the neck of the uterus, and
gives branches to the vagina.
You must not expect to meet with uniformity in the
distribution of these vessels in all subjects: sometimes
the gluteal and pudic arteries come off by one trunk,
sometimes the pudic and sciatic, &c. &c.
GUIDE TO ANATOMY. 199
2. VEINS.
The veins attend the arteries and their ramifications;
they unite to form the internal iliac vein, except the
veins from the rectum, named Hcemorrhoidales, which
ascend along its back part to join the inferior mesen-
teric vein.
3. NERVES.
The nerves met with in this dissection, consist of
numerous twigs sent off from the lumbar and sacral
nerves to supply the parts about the pelvis.
But, in this dissection, we meet with three pair of
large nerves, which have their course through the
pelvis, and pass to the thigh.
1. Course of the Anterior Crural Nerve while
in the pelvis. The anterior crural nerve is formed
by branches of the first, second, third, and fourth
lumbar nerves; at its origin, it lies under the psoas
magnus, and, as it descends, passes betwixt the psoas
magnus and iliacus internus, till having passed under
Poupart's ligament, it emerges from betwixt those
muscles, and appears on the outer side of the inguinal
artery.
2. Course of the Obturator Nerve within the
pelvis. This nerve is formed by branches of the
second, third, and fourth lumbar nerves: it lies under
the internal border of the psoas magnus, descends
into the pelvis, and goes obliquely downwards, to
accompany the obturator artery through the thyroid
hole.
3. Course of the Great Sciatic Nerve within
the pelvis. This nerve arises by branches from the
fourth and fifth lumbar, and first three sacral nerves,
which unite together to form the largest nervous
trunk in the body. The nerve passes betwixt the
pyriformis and gemini, and thus escapes from the
200 LONDON DISSECTOR, OR
back part of the pelvis by the sciatic notch. Some-
times one of the branches goes through the pyriformis,
and joins the sciatic trunk at the back of the pelvis.
ARTERIES, VEINS, AND NERVES ON
THE FORE PART AND INSIDE
OF THE THIGH.
I. ARTERIES.
The Femoral Artery may be said to pass along
the inside of the thigh, where it emerges from under
Poupart's ligament; it lies cushioned on the fibres of
the psoas magnus, is called the Inguinal artery, and
is very nearly in the mid space between the angle of
the pubis, and the anterior superior spine of the ilium,
nearer, however, by a finger's breadth to the former;
having left the groin, it assumes the name of Femoral,
and, in its course down the thigh, runs over the fol-
lowing muscles: — The pectinalis, part of the adductor
brevis, where that muscle projects betwixt the pecti-
nalis and adductor longus; the whole of the adductor
longus, and about an inch of the adductor magnus: It
then slips betwixt the tendon of the adductor magnus
and the bone, and, entering the ham, becomes the
Popliteal artery. To find the artery in any part of
its course from the crural arch to the tendinous opening,
turn out the foot, ascertain the place of that vessel at
the crural arch, according to the above description,
and then draw a straight line downwards. In this
course, it has the belly of the vastus internus situated
on its outside; it lies between the origin of that mus-
cle, and the tendinous insertion of the muscles over
which it crosses; and there is a strong interlacing of
the tendinous fibres, forming a deep groove for the
artery; it is also invested by a firm sheath, which
GUIDE TO ANATOMY 201
consists of condensed cellular membrane, intermixed
with some tendinous fibres: — For some inches below
Poupart's ligament, this artery is on its fore part only
covered by cellular substance, absorbent glands, and
the general fascia of the thigh; but, meeting with the
inclined line of the sartorius, it is, during the rest of
its course, covered by that muscle. It perforates the
tendon of the adductor magnus, at the distance of
rather more than one-third of the length of the bone
from its lower extremity.
Observe that in popliteal aneurism the artery may
be taken up either at the upper or inner, the lower or
outer, margin of the Sartorius, or immediately behind
that muscle: of which situations the first is the best,
the second next, and the third by far the least eligible.
BRANCHES OF THE FEMORAL ARTERY.*
The A. Profunda comes off from the femoral
artery at the distance of two, three or four inches from
Poupart's ligament; it is nearly as large as the femoral
itself, runs down for some little way behind it, and
terminates in three or four branches, which, perfora-
ting the triceps adductor, are named Arterle Per-
forantes. These, ramifying in every direction,
supply all the great mass of muscles situated on the
back part of the thigh, and inosculate largely with the
sciatic, gluteal, and obturator arteries. The profunda
also sends off two considerable branches, which, en-
circling the upper part of the thigh, are named Cir-
cumflexa Interna, and Circumflexa Externa.
The profunda is the only branch of the femoral
artery which is constant in its size and situation; for
though, during the whole of its course, the femoral
gives off branches to the muscles, yet these muscular
arteries vary much, sometimes coming off from the
♦The Epigastrica and Circumflexa ilii are before described as branches
of the inguinal artery.
202 LONDON DISSECTOR, OR
great artery, sometimes from the profunda, sometimes
coming off as a large single trunk which subdivides,
while at other times there are three or four distinct
arteries.
The branches of the femoral artery may be enume-
rated as follows: — 1. Some twigs to the inguinal
glands, and some to the external parts of generation,
named Pudicae Externae. 2. Muscularis interna.
3. Muscularis externa. 4. Profunda.
The Obturator Artery, arteria obturatrix, which
is a branch of the internal iliac artery, passes through
the notch at the upper part of the foramen thyroideum,
and ramifies on the deep seated muscles at the upper
and inner part of the thigh.
2. VEINS.
The Femoral Vein adheres closely to the femoral
artery in its passage out of the abdomen, and accom-
panies it in its course down the thigh, where it passes
under Poupart's ligament; it lies on the inside of the
artery, but, as it descends, it turns more and more
posteriorly, so that where they perforate the tendon
of the adductor magnus, the vein is situated fairly
behind the artery.
Its branches correspond to those of the femoral ar-
tery; but about an inch below Poupart's ligament, it
receives the vena saphena major, to which there is no
corresponding artery.
The Obturator Vein accompanies the obturator
artery, and has the same distribution.
3. nerves.
Nervus Cruralis Anterior, or the Anterior
Crural nerve, where it passes from under Poupart's
ligament, lies about half an inch on the outside of the
GUIDE TO ANATOMY. 203
femoral artery; it immediately divides into a number
of branches, which supply the muscles and integuments
on the fore part and outside of the thigh. A consider-
able branch, however, accompanies the femoral ar-
tery, crosses that vessel where it is about to perforate
the adductor magnus, runs behind the sartorius, and
appears as a cutaneous nerve on the ipside of the knee:
proceeding downwards on the inside of the leg, it is
largely distributed over the tibia, is intricated with the
vena saphena major, and terminates on the inner ankle,
and upper part of the foot. This branch is named
Nervus Saphenus, or Cutaxeus Lo>*gus.
Another branch, which is distributed to the vastus
internus, generally runs for some way in company with
the femoral vessels.
Nervus Obturator, or the obturator nerve, is
found accompanying the obturator artery and vein; it
has the same distribution, and some branches extend
as far as the internal condyle of the thigh bone, and
communicate with the nervus saphenus.
VESSELS AND NERNES ON THE POS-
TERIOR PART OF THE THIGH.
ARTERIES.
1. Arteria Glutea, or Iliaca Posterior. —
This is the largest branch of the internal iliac artery;
it passes out of the pelvis at the upper part of the
sciatic notch. On raising the gluteus maximus and
medius, this artery is seen coming over the pyriformis,
betwixt the superior edge of that muscle and the infe-
rior edge of the os ilium (where that bone forms the
upper part of the sciatic notch,) and immediately
204 LONDON DISSECTOR, OR
behind the posterior fibres of the gluteus minimus.
The principal trunk passes under the gluteus medius,
and ramifies on the dorsum of the os ilium; other large
branches are also continued to the gluteus maximus,
and the muscles situated on the back part of the
pelvis.
2. Arteria Sciatica, vel Ischiatica, is another
large branch of the internal iliac, which comes out
from under the pyriformis, between the lower edge
of that muscle and the superior sacro-sciatic ligament;
it lies upon the back part of the hip, under the gluteus
maximus; — its principal branches descend between
the trochanter major and tuberosity of the ischium; it
sends other twigs round towards the anus and peri-
neum.
Both these arteries inosculate with the other
branches of the internal and external iliac.
The Veins correspond exactly to the arteries.
They terminate in the internal iliac vein.
NERVES.
Nervus Sciaticus, vel Ischiaticus, or the Great
Sciatic Nerve, is seen coming out of the pelvis, along
with the sciatic artery, below the pyriformis. It
descends over the gemini and quadratus femoris in the
hollow betwixt the great trochanter and the tuberosity
of the ischium, — runs down the back part of the thigh,
anterior to, i. e. nearer the bone than the hamstring
muscles; being situated between the anterior surface
of the semimembranosus, and the posterior surface of
the triceps adductor longus. After sending off the
peroneal nerve, it arrives in the ham, and becomes
the Popliteal Nerve. In this course it gives off
several branches to the muscles and integuments. It
sometimes perforates the belly of the pyriformis by
distinct trunks, which afterwards unite.
GUIDE TO ANATOMY. 205
DISSECTION OF THE HAM AND FASCIA ON
THE BACK PART OF THE LEG.
On removing the integuments from the back part of
the knee joint and leg, we observe a Fascia, which
covers the great vessels and the muscles. It is evi-
dently continued from the great fascia of the thigh, is
strengthened by adhesions to the condyles of the femur,
and the head of the fibula, and is prolonged upon the
muscles on the back of the leg.
Upon dissecting back that part of the fascia which
covers the ham, the Great Sciatic Nerve appears,
lying between the outer and inner hamstring muscles.
This nerve, having given off branches about the ham,
and to the integuments on the back of the leg, divides
at some distance above the condyles of the femur into
two large branches.
1 . The Greater Nerve continues its course betwixt
the heads of the gastrocnemii muscles. In the ham
it is named the Popliteal Nerve, and where it
descends in the leg, the Posterior Tibial.
2. The Smaller Nerve, which is the external branch,
is named the Peroneal or Fibular Nerve; it passes
outwards and obliquely downwards, runs between the
external head of the gastrocnemius, and the tendon of
the biceps flexor cruris; and sinks among the muscles
which surround the head of the fibula.
BRANCHES OF THE PERONEAL NERVE.
(I.) Cutaneous branches are sent off from the pero-
neal nerve at its uppermost part over the gastrocne-
mius to the integuments in the back part of the le°",
and outer side of the foot. Branches also are distri-
buted about the joint.
(2.) A large branch, the Anterior Tibial Nerve,
passes under the flesh of the peroneus lonarus and
18
206 LONDON DISSECTOR, OR
extensor longus digitorum, where those muscles arise
from the heads of the fibula and tibia; and comes in
contact with the anterior tibial artery, which it accom-
panies down the leg.
(3.) Another branch passes into the upper extremity
of the peroneus longus, and is continued in the substance
of that muscle for some space. It then emerges from
beneath it, and continues its course under the muscles
on the fore part and outside of the leg; it pierces this
fascia, and, becoming cutaneous, is lost on the ankle
and upper surface of the foot.
Below the great sciatic nerve, there is much cellular
membrane and fat, which being removed, the Great
Popliteal Vein is exposed. It adheres to the Pop-
liteal Artery, which lies under it close upon the
bone.
Arteria Poplitea is the trunk of the Femoral,
which assumes that name, after it has perforated the
tendon of the triceps. It lies between the condyles
of the femur, close upon the bone, and descends
between the heads of the gastrocnemius. It runs
over the popliteus, and under the gastrocnemius, that
is, in the erect position it is anterior to the gastroc-
nemius, and posterior to the popliteus: at the lower
edge of the popliteus, the popliteal artery divides
into the Anterior and Posterior Tibial Arte-
ries.
branches.
1. Two Perforating Arteries come off from
the artery immediately after it has entered the ham;
they are small, and perforate from the ham to the
fore part of the thigh.
2. Articular Arteries are four or five small
twigs, ramifying over the knee-joint and neighbouring
muscles, inosculating with one another, and with the
arteries below the knee.
GUIDE TO ANATOMY. 207
3. Two branches are sent to the two heads of the
gastrocnemii muscles; twigs are also given to the
soleus, plantaris, &c.
The Popliteal Vein receives branches corres-
ponding to those of the artery; it lies behind the
artery in the erect posture.
About two inches above the condyle, it receives
the Vena Saphena Minor, which returns the blood
from the outer side of the foot; — the trunk of this
vein lies under the fascia.
OF THE VESSELS AND NERVES
IN THE FORE PART OF THE
LEG AND FOOT.
1. arteries.
Arteria Tibialis Antica. — The anterior tibial
artery passes from the ham betwixt the inferior edge
of the popliteus, and the superior fibres of the soleus,
and then through a large perforation in the interosse-
ous ligament, to reach the fore part of the leg; this
perforation is much larger than the size of the artery,
and is filled up by the fibres of the musculus tibialis
posticus, which may thus be said to arise from the
fore part of the tibia. The artery then runs down
close upon the middle of the interosseous ligament,
between the tibialis anticus and extensor proprius
pollicis; below the middle of the leg, it leaves the in-
terosseous ligament and passes gradually more for-
wards; it crosses under the tendon of the extensor
proprius pollicis,* and is then situated between that
* It is crossed by that tendon just abore the lower head cf the tibia,
while under the annular ligament.
208 LONDON DISSECTOR, OR
tendon, and the first tendon of the extensor longus
digitorum: at the ankle it runs over the fore part of
the tibia, being now situated more superficially; then
over the astragalus and os naviculare, and over the
junction of the os cuneiforme internum and medium;
crossing under that tendon of the extensor brevis dig-
itorum which goes to the great toe. Arriving at the
space between the bases of the two first metatarsal
bones, it plunges into the sole of the foot, and immedi-
ately joins the plantar arch.
branches:
1. A. Recurrens, which ramifies over the fore
part of the knee, inosculating with the articular arte-
ries.
2. Numerous twigs to the tibialis anticus, extensor
pollicis, and other muscles on the fore part of the leg.
3. A. Malleolaris Interna ramifies over the
inner ankle, and inosculates with the peroneal and pos-
terior tibial arteries.
4. The External Malleolar ramifies over the
outer ankle.
5. The Tarsal and Metatarsal Arteries, are
two small branches which cross the tarsal and
metatarsal bones, and pass obliquely to the outer edge
of the foot.
From the tarsal or metatarsal artery come off the
Interosseal Arteries, which supply the interosseal
spaces, and the back part of the toes.
6. A large branch comes off from the anterior tibial,
where it is about to plunge into the sole of the foot;
it runs along the space betwixt the first two metatar-
sal bones, and at the anterior extremity of those bones,
bifurcates into,
(1.) A. Dorsalis Hallucis, a considerable branch
which runs on the back part of the great toe.
GUIDE TO ANATOMY. 209
(2.) A branch which runs on the inner edge of the
toe next to the great one.
2. VEINS.
The Anterior Tibial Vein consists of two
branches, which accompany the artery and its ramifi-
cations.
3. nerves.
The Anterior Tibial nerve is a branch of the
peroneal nerve; it is seen in the ham arising from the
peroneal, and crossing under the muscles on the out-
side of the fibula: — It emerges from under the exten-
sor longus digitorum, comes in contact with the ante-
rior tibial artery, and accompanies it down the leg; it
is distributed on the back of the foot and toes.
VESSELS AND NERVES OF THE
POSTERIOR PART OF THE
LEG.
1. ARTERIES.
Arteria Tibialis Postica. The posterior tibial
artery, which is the continued trunk of the popliteal,
sinks under the origins of the soleus, and runs down the
leg between that muscle and the more deeply seated
flexors of the toes: It does not lie in immediate con-
tact with the fibres of the flexors, but, like the femo-
ral artery, is invested by a strong sheath of condensed
cellular membrane. It is, together with its veins and
accompanying nerve, also supported by the fascia
which binds down the deep seated muscles. As it
descends, it gradually advances more forwards, fol-
18*
210 LONDON DISSECTOR, OR
lowing the course of the flexor tendons: it passes be-
hind the inner ankle, in the sinuosity of the os calcis,
lying posterior to the tendon of the flexor longus
digitorum, and anterior to that of the flexor longus
pollicis. Here it is close upon the bone, and in the
living subject its pulsation may be felt. It sinks under
the abductor pollicis, arising from the os calcis, and
immediately divides into two branches:
(LYThe^ Internal Plantar Artery is the smaller, and
ramifies among the mass of muscles situated on the
inner edge of the sole of the foot.
(2.) The External Plantar Artery directs its course
outwards, and having reached the metatarsal bone of
the little toe, forms the Plantar Arch, which crosses
the three middle metatarsal bones obliquely, about
their middle, and terminates at the space betwixt the
first two metatarsal bones, where the trunk of the an-
terior tibial artery joins the arch. The convexity of
this arch is towards the toes, and sends off the follow-
ing branches.
a, A small branch to the outside of the little toe.
6, Ramus digitalis primus, or the first digital artery,
which runs along the space between the last two me-
tatarsal bones, and bifurcates into two branches, one
to the inner side of the little toe, and the other to the
outer side of the next toe.
c, The second digital artery, which runs along the
next interosseous space, and bifurcates in a similar
manner.
d, The third digital artery.
e, The fourth, or great digital artery, which sup-
plies the great toe, and the inner side of the toe next
to it.
The concavity of the arch sends off the interos-
seal arteries, three or four small twigs, which go to
the deep-seated parts in the sole of the foot, and,
perforating between the metatarsal bones, inosculate
GUIDE TO ANATOMY. 211
with the superior interosseal arteries on the upper
side of the foot.
The branches of the Posterior Tibial Artery in the
leg are,
1. The Peroneal Artery, which comes off from
the tibial a little after it has sent off the anterior tibial,
of which this artery is sometimes a branch; it is
generally of a considerable size, sometimes nearly as
large as the tibial itself; it runs upon the inside of the
fibula, giving numerous branches to the peroneal
muscles and flexor of the great toe; but its course is
irregular and inconstant. At the lower part of the
leg, it splits into,
a, A. Peronea Anterior, which passes betwixt
the lower heads of the tibia and fibula, to the fore-
part of the ankle, where it is lost.
fe, A. Peronea Posterior is properly the termi-
nation of the artery; it descends along the sinuosity
of the os calcis, inosculating with the branches of the
tibialis postica, and terminates in the posterior part
of the sole of the foot.
2. Muscular branches arise from the artery as it
descends; twigs also are sent over the heel and ankle.
2. VEINS.
Vens: Tibiales Postice. — The posterior tibial
veins are generally two in number; they accompany
the artery, and terminate in the popliteal vein; they
are formed of branches, which correspond to those
of the artery.
3. NERVES.
The Posterior Tibial Nerve, which is the con-
tinuation of the great sciatic nerve, sinks below the
soleus, and accompanies the posterior tibial artery; it
gives off numerous filaments to the muscles in its
neighbourhood. At first it continues, as in the ham,
212 LONDON DISSECTOR, OR
immediately behind the artery, but it gradually gets
on the outside of it as it descends; so that where
they pass along the sinuosity of the os calcis, the
nerve is situated close in contact with the side of the
artery, but nearer to the projection of the heel than
that vessel is. With the artery, it divides into,
1 . The internal plantar nerve, and,
2. The external plantar nerve. — These nerves sup-
ply the muscles and integuments in the sole of the
foot.
OF THEVESSELS OF THE BRAIN.
The arteries ramify largely on the pia mater, before
they enter the substance of Ihe brain; they come
from two large branches.
1. The Internal Carotid Artery enters the
skull by a winding course through the foramen carot-
icum of the temporal bone. After passing through
the cavernous sinus, it divides into three branches:
1. Anterior cerebri, passing between the two anterior
lobes; 2. Media cerebri, entering the fissura sylvii;
3. Ramus communicans, uniting with the basilar. The
carotid, while in the cavernous sinus, gives off the
arteria ophthalmica, which passes through the fora-
men opticum to the eye and its appendages.
2. The Vertebral Artery arises from the sub-
clavian, ascends through the foramina in the trans-
verse processes of the cervical vertebrae, enters the
cranium by the foramen magnum, and gives branches
to the dura mater and spinal marrow. — Uniting with
its fellow, it forms the basilar artery, which gives
branches to the internal ear, branches to form the cir-
culus arteriosus, and then divides into two large
branches called Posteriores Cerebri, which sup-
ply the back parts of the cerebrum.
GUIDE TO ANATOMY. r 213
The Veins pour their blood into the sinuses, which
are numerous. None of these veins require particu-
lar attention, except the ophthalmic vein, which
passes through the foramen lacerum orbitale superius.
The principal sinuses, viz. the longitudinal, the two
lateral, the inferior longitudinal, &c. have been de-
scribed in the dissection of the brain. The remainder
of these sinuses are situated in folds of the dura
mater, but are not regular in their situation. They
transmit their blood to the longitudinal and lateral
sinuses, which terminate in forming the internal jugu-
lar veins.
For the description of the meningeal arteries
see page 98, and for the nerves of the brain, see
page 108.
OF THE VESSELS AND NERVES
SEEN IN THE DISSECTION
OF THE NECK.
ARTERIES.
Starting from the arch of the aorta, the student
will see three large arteries coming off from the up-
per part of that arch, viz: the arteria innominata, the
left carotid and the left subclavian. From the innom-
inata proceed the right common carotid, and the
right subclavian.
The carotid artery ascends from the thorax by the
side of the trachea; on its outer side it has the inter-
nal jugular vein, and behind it the par vagum and in-
tercostal nerves. All these parts are connected and
inclosed by condensed cellular membrane, which forms
for them a kind of sheath. At the bottom, and in
the middle of the neck, the carotid is covered by the
sterno-cleido-mastoideus; at the upper part, by adipose
214 LONDON DISSECTOR, OR
membrane, absorbent glands, and the platysma niyoi-
des. It lies deep on the muscles of the spine, and
gives off no branches, until it reaches the space be-
tween the larynx and the angle of the jaw, just below
the cornu of the os hyoides, where it divides into the
external and internal carotids.
Of the two, the internal carotid is situated more
outwardly; it passes deep to the base of the cranium,
where it enters the foramen caroticum, to supply the
brain.
The external carotid immediately begins to send
off branches.
Anteriorly it sends off,
1. The A. Thyroidea Superior. — This artery
passes downwards and forwards, to ramify on the
thyroid gland, where it inosculates with the artery of
the other side, and with the inferior thyroid arteries.
In this course, it sends ramifications to the integuments,
the outside of the larynx, the muscles, &c. and one
remarkable branch, the A. Laryngea, which some-
times arises from the trunk of the external carotid; it
is a small artery which divides betwixt the os hyoides
and thyroid cartilages, to supply the internal parts of
the larynx.
2. A. Lingualis, vel Ranina. — The sublingual ar-
tery passes over the cornu of the os hyoides, then
behind the mylo hyoideus, over the stylo-glossus,
hyo-glossus, and genio-hyo-glossus, to which it gives
branches, and terminates in running along the inferior
part of the tongue from its base to its apex. It gives
branches, to the muscles about the chin, and to the
substance and back part of the tongue.
3. A. Maxillaris Externa. — The external max-
illary artery passes under the stylo-hyoideus and pos-
terior belly of the digastricus, then buries itself under
the submaxillary gland. It runs over the lower jaw
before the anterior edge of the masseter muscle, to
supply the face.
GUIDE TO ANATOMY. 215
In its passage, it gives off numerous branches. — One
is worthy of notice, which runs along under the line
of the lower jaw, and passing over the jaw near the
symphysis, supplies the chin. Other twigs supply
the submaxillary gland, &c.
Posteriorly the carotid sends off,
4. A. Occipitalis. — The occipital artery crosses
backwards and upwards, over the internal jugular
vein and internal carotid artery, under the belly of
the digastric muscle: it passes through a slight groove
in the mastoid process below its great fossa, and rami-
fies on the back part of the head. A remarkable
branch of the occipital passes towards the base of the
skull, to inosculate near the foramen magnum occipi-
tis, with branches from the vertebral and posterior
cervical arteries.
5. A. Pharyngea is a small branch of the carotid,
which passes inwards to the pharynx and base of the
skull.
6. Posterior Auris, which passes backwards
and upwards in the fold between the ear and scalp,
and is distributed on the integuments of the head.
The external carotid ascends behind the angle of
the jaw, and enters the parotid gland, where it divides
into,
7. A. Maxillaris Interna.
8. A. Temporalis.
9. A. Transversalis Faciei.
These arteries will be described in the dissection
of the face.
veins.
The Internal Jugular Vein is a continuation
of the lateral sinus which passes through the foramen
lacerum in the base of the cranium. It comes out
deep from under the angle of the jaw, and in its course
down the neck, it runs on the outer side of the
216 LONDON DISSECTOR, OR
carotid artery, before it reaches the thorax; it passes
rather more forwards than the artery, to join the sub-
clavian vein.
Its branches accompany the ramifications of the
external carotid. At first the vein which accompa-
nies each artery is a single branch, but it soon subdi-
vides, so that two veins accompany one artery.
NERVES.
1. The Eighth Pair, or Par Vagum. — On sepa-
rating the internal jugular vein, and trunk of the caro-
tid artery, the par vagum is seen lying in the same
sheath of cellular substance with those vessels. It
lies in the triangular space formed betwixt the back
part of the artery and vein, and the subjacent mus-
cles. This nerve comes out of the foramen lacerum
with the jugular vein; hence it adheres to that vein
more closely than to the artery or muscles; it runs
down the neck behind these vessels.
In this course it gives off several nerves.
(1.) At the base of the cranium, it sends off several
filaments, which are connected with the other nerves
coming out of the base of the skull; such as the ninth
pair, the superior cervical ganglion of the intercos-
tal, &c.
(2.) Nervus Glosso-Pharyngeus is sent off from
the eighth pair, deep under the angle of the jaw. It
passes behind the carotids towards the muscles aris-
ing from the styloid process; one principal branch of
it passes between the stylo-pharyngeus and stylo-
glossus to the tongue, while other twigs run behind
the stylo-pharyngeus, to supply the pharynx.
(3.) Nervus Laryngeus Superior, vel Inter-
nus. — The superior or internal laryngeal nerve passes
behind the internal carotid artery, obliquely, down-
wards and forwards; then, under the hyo-thyroideus
GUIDE TO ANATOMY. 217
muscle, it plunges betwixt the os hyoides and thyroid
cartilage, accompanying the laryngeal artery, and
supplying the internal parts of the larynx. .
(4.) In the neck, also, the par vagum gives off fila-
ments to the cervical ganglions of the intercostal
nerve, and to communicate with the other nerves of
the neck. Filaments also unite with twigs of the
intercostal, and run down over the carotid artery to
the great vessels of the heart, where they form the
superior cardiac plexus.
The par vagum enters the thorax by passing be-
twixt the subclavian artery and vein.
2. The Intercostal, or Great Sympathetic
Nerve. — This nerve lies behind the carotid, in the
cellular membrane, betwixt that vessel and the mus-
cles covering the vertebrae of the neck. It is distin-
guished from the par vagum by being smaller, lying
nearer the trachea, and adhering to the muscles of the
spine; also by its forming several ganglions. It arises
from the sixth pair in the cranium, and comes out by
the same foramen as the carotid artery.
Immediately after its exit from the skull, it forms
the Superior Cervical Ganglion, which is very
long, and of a reddish color. The nerve afterwards
becomes smaller, and descends; and opposite the fifth
or sixth cervical vertebra, it forms another swelling,
the Inferior Cervical Ganglion. Sometimes it
has another ganglion about the fourth or fifth vertebra
of the neck, the Middle Cervical Ganglion; but
this is not a constant appearance. The nerve then
passes behind the subclavian artery into the thorax.
The branches of the intercostal nerve are nume-
rous, and they generally pass off from the ganglions.
Immediately below the base of the cranium, twigs go
to the eighth and ninth pairs, and to the upper cervical
nerves. In the middle of the neck, some twigs pass
over the carotid; others go to the parts covering - the
19
218 LONDON DISSECTOR, OR
trachea, and uniting with filaments of the par vagum,
form the external laryngeal nerves; others unite with
the descendens noni, or descending branch of the ninth
pair, and some filaments assist the twigs of the par
vagum to form the superior cardiac nerve. In the
lower part of the neck, twigs are sent to communicate
with the cervical nerves, &c.
3. The Ninth Pair, Nervus Hypo-glossus, or
Lingual nerve, having left the skull by the anterior
condyloid foramen, is connected with the eighth pair
and intercostal nerve. Like them, it lies deep, and
comes out from under the angle of the jaw. It is seen
passing from behind the internal jugular vein, and then
over the carotid artery, running betwixt these two
vessels. It next passes under the mylo-hyoideus,
running over the stylo-glossus, hyo-glossus, and genio-
hyo-glossus, which last muscle its numerous branches
perforate.
Branches. — While the nerve is passing betwixt
the jugular vein and the carotid artery,- it sends off the
Descendens Noni. — This small and delicate nerve
descends on the fore part of the vein and artery, and
is distributed to the muscles on the anterior part of
the trachea. It is joined by filaments of the cervical
nerves.
4. The Lingual Branch sent off by the third
branch of the fifth pair of nerves, is also seen in the
dissection of the neck. It is found under the mylo-
hyoideus; it lies close upon the lower edge of the
jaw-bone, betwixt the inferior edge of the pterygoid-
eus internus and the upper part of the mylo-hyoideus.
It gives numerous twigs to the sublingual gland and
submaxillary duct, which are situated near it, and is
lost in the substance of the tongue.
5. Nervus Accessorius ad Par Vagum.— The
accessory nerve, having passed out of the cranium
with the par vagum, separates from it, passes behind
GUIDE TO ANATOMY. 219
the internal jugular vein obliquely downwards and
backwards; it perforates the mastoid muscle, and is
distributed to the trapezius and muscles about the
shoulder, it is much connected with the third and
fourth cervical nerves.
6. The Seven Cervical Nerves come out from
the foramina betwixt the vertebrae of the neck. Thev
send numerous branches to the muscles, &c, on the
side of the neck, and communicate by filaments with
all the other nerves in the neck.
In this stage of the dissection, we may also see,
7. The Phrenic Nerve, formed by branches of
the third and fourth cervical nerves. This small nerve
lies upon the belly of the anterior scalenus muscle,
and dives into the thorax, betwixt the subclavian
artery and vein.
8. The Recurrent Nerve, a branch sent off from
the par vagum in the thorax, is also seen in the neck.
Dissect between the under surface of the trachea and
oesophagus at the lower part of the neck, and you will
find the recurrent nerve situated there.
9. The upper part of th© OmSAT Brachial Plex-
us may be seen arising on the side of the neck, from
the lower cervical nerves, and passing behind the an-
terior scalenus, to reach the arm.
A general view of the distribution of the spinal
nerves may be usefully subjoined in this place, to
complete the description of the nerves.
1. The Cervical Nerves consist of seven pairs;
they spread their branches over the side of the neck,
and to the muscles moving the head and shoulders.
The superior nerves send branches to the side of the
head, and the inferior to the upper part of the chest
and back. They also communicate freely with each
other, and with all the neighboring nerves; — high in
the neck, and under the jaw, with the portio dura of
the seventh pair, with the fifth, eighth, and ninth pairs,
220 LONDON DISSECTOR, OR
and with the great sympathetic; — towards the middle
of the neck, with the descend ens noni, the sympathetic
and eighth pair, and in the lower part of the neck with
the sympathetic.
The Phrenic Nerve is formed by branches of the
third, fourth, and fifth cervical nerves, passes obliquely
down the neck through the thorax, then on each
side of the pericardium, and is distributed to the dia-
phragm.
The Axillary Plexus is formed by the principal
parts of the trunks of the fourth, fifth, sixth, and
seventh cervical, and first dorsal nerves.
2. The Dorsal Nerves are twelve pairs. They
arise from the spinal marrow in the same manner as
the cervical. Each nerve emerges betwixt the heads
of the ribs, gives twigs to the great sympathetic nerve,
and twigs which pierce backwards to the muscles of
the back; then, entering the groove in the lower edge
of each rib, it accompanies the intercostal artery, and
runs towards the anterior part of the thorax, supply-
ing the great muscles of the chest, giving twigs to the
diaphragm, and muscles of the abdomen.
3. The Lumbar Nerves are five pairs. They
arise in the same manner; their trunks are covered by
the psoas magnus muscle. Each nerve gives twigs to
the muscles of the loins and back, and to the sympa-
thetic nerves, and runs obliquely downwards to supply
the abdominal muscles and integuments of the groin
and scrotum; but the trunks of these nerves assist in
forming the nerves of the thigh.
4. The Sacral Nerves are five on each side,
arising from the cauda equina. They come out through
the anterior foramina, and send small branches to the
neighboring parts; but the great trunks of these nerves
are united with the lumbar nerves to form the nerves
of the lower extremity, viz.
(1.) The Anterior Crural Nerve, passing out
GUIDE TO ANATOMY. 221
under Poupart's ligament to the extensor muscles of
the leg, is formed by branches of the first, second,
third, and fourth lumbar nerves.
(2.) The Obturator Nerve, leaving the pelvis by
the thyroid holes, and being distributed to the deep
seated muscles on the inside of the thigh, arises from
branches of the second, third, and fourth lumbar
nerves.
(3.) The Ischiatic or Sciatic Nerve, the greatest
nerve of the body, passes out from the back part of
the pelvis, through the sacro-sciatic notch, and takes
its course along the back of the thigh, to supply the
thigh, leg, and foot; it is formed from the last two
nerves of the loins and the first three of the sacrum.
All these nerves of the spine communicate freely by
numerous twigs, and by the intervention of
The Great Sympathetic Nerve, or Intercos-
tal. This nerve, originally derived from the sixth
pair, and from some filaments of the fifth, passes out
of the cranium with the carotid artery. It then de-
scends through the neck, and forms three ganglions in
its course, which give twigs to the neighboring parts,
and are joined by filaments from the cervical nerves,
and the eighth and ninth pairs. The intercostal then
enters the thorax, and descends by the side of the
vertebrae, behind the pleura, giving filaments, which,
joining with twigs of the eighth pair, form several
plexuses to supply the heart, lungs, &c. In the ab-
domen it descends on the lumbar vertebrae, and at last
terminates in the pelvis on the extremity of the
coccyx.
While in the thorax, it gives off a branch, which,
uniting with branches of the dorsal nerves, forms
The Anterior Intercostal, or Splanchnic
Nerve. — This nerve, passing betwixt the crura of the
diaphragm, enters the abdomen, forms the semilunar
19*
222 LONDON DISSECTOR, OR
ganglion, and is distributed by numerous plexuses to
all the abdominal viscera.
The Eighth pair, or par vagum, has also a very
long course; it arises in the head, passes through the
neck, to which it gives several branches. It enters
the thorax anterior to the subclavian artery; here it
gives off a remarkable branch, called the Recurrent,
because it is reflected round the arch of the aorta on the
left side, and round the subclavian artery on the right,
and ascends to be distributed on the trachea, oesopha-
gus, and larynx. The nerve then passes through the
thorax, and, entering the abdomen, terminates in the
stomach; in this course it has frequent communications
with the great sympathetic, which it assists in forming
the different plexuses that supply the thoracic and
abdominal viscera. It is distributed to the heart, lungs,
liver, spleen, stomach, and duodenum.
COURSE OF THE SUBCLAVIAN
ARTERY ON EACH SIDE.
The subclavian artery passes upwards and out-
wards, runs under the clavicle, and over the middle
of the first rib; it passes between the bellies of the
anterior and middle scaleni muscles, then runs under
the arch of the pectoralis minor, and enters the axilla,
where it assumes the name of Axillary Artery.
The order in which the following arteries are sent
off from the subclavian varies much; sometimes they
come off singly, at other times in large trunks, which
subdivide.
Backwards the subclavian sends off,
1. The Vertebral artery. — This artery arises
from the back part of the subclavian, passes outwards
and enters the foramen in the transverse process of
GUIDE TO ANATOMY. 223
the last cervical vertebra, and ascends through the
transverse processes of the vertebrae, to enter the
foramen magnum of the occipital bone.
2. The Inferior Thyroid Artery ascends ob-
liquely inwards, passes behind the internal jugular
vein, to ramify on the thyroid gland, where it inos-
culates largely with the superior thyroid arteries.
Branches from this artery pass to the trachea and
cesophagus, to the muscles of the neck, and of the
scapula: one of these is the supra scapulary artery.
(See the account of the branches of the axillary
artery.)
3. A. Cervicalis Anterior, vel Profunda, passes
deep to the muscles situated on the fore part of the
cervical vertebrae, and ascends as high as the base of
the skull.
4. A. Cervicalis Posterior, vel Superficialis,
is larger than the last; it ascends obliquely outwards,
generally passes betwixt the transverse processes of
the last cervical and first dorsal vertebrae, and ascends
on the back part of the neck, deeply seated; some of
its branches pass down the back superficially.
Anteriorly, the subclavian artery gives off,
5. A. Mammaria Interna. The internal mam-
mary arises from the fore part of the subclavian, op-
posite the cartilage of the first rib; it runs down on the
inside of the cartilages of the ribs, and terminates in
the abdominal muscles, where it inosculates with the
epigastric. It is a large artery, and its branches are
very numerous. They pass to the external muscles
of the chest, to the intercostal muscles, pleura, Sac. It
also sends off the Arteria Phrenica Superior, vel
comes nervi phrenici, which, with two veins, accom-
panies the phrenic nerve to the diaphragm.
6. The subclavian artery gives twigs to the root of
the neck, and to the muscles about the scapula.
7. A. Intercostalis Superior. Frequently a
224 LONDON DISSECTOR, OR
trunk comes off from the subclavian, especially on the
right side, which passes downwards and backwards,
and lodges itself by the spine, to supply the two or
three superior intercostal spaces.
COURSE OF THE SUBCLAVIAN VEIN.
The subclavian vein is situated anteriorly to the
subclavian artery; it passes inwards behind and under
the subclavius muscle, and before and over the belly
of the anterior scalenus (so that this last muscle lies
betwixt the vein and artery.) It runs over the first
rib, from under the arch of the pectoralis minor, where
it is found in contact with the axillary artery, and is
called the Axillary Vein.
The branches of this vein accompany and corres-
pond to the ramifications of the subclavian artery,
returning the blood from the thyroid gland, neck, chest,
intercostal spaces, &c. The subclavian vein also
receives the internal jugular, which passes down be-
hind the clavicle.
THE COUR?E OF THE BRACHIAL PLEXUS OF NERVES
May also be examined. This plexus is formed by
branches of the four lower cervical and first dorsal
nerves, which pass between the anterior and middle
scaleni muscles into the axilla. In this passage they
are situated higher up than the artery.
DISSECTION OF THE AXILLA OR
ARMPIT.
There is a considerable resemblance in the dis-
section of the axilla to that of the ham or groin; in
each of these situations we meet with important blood-
GUIDE TO ANATOMY. 225
vessels and nerves, closely connected, embedded in
adipose membrane, and seated in the flexure of a
joint.
The axilla is formed by two muscular folds which
bound a middle cavity. The anterior fold is formed
by the pectoralis major passing from the thorax to
the arm, the posterior by the latissimus dorsi coming
from the back.
In the intermediate cavity there is a quantity of
cellular membrane and absorbent glands, covering
and connecting the great vessels and nerves. This
cellular and adipose membrane is continued from the
interstice above the clavicle betwixt the edges of the
trapezius and mastoid muscles. All the space before
the root of the neck above the first rib, and under the
clavicle and coracoid process of the scapula, and the
interstices of the muscles passing through that space,
are filled up by a quantity of adipose membrane; and
this is not exactly similar to the fat in other parts of
the body; it is more granulated, watery, and of a
reddish color; it surrounds the great vessels and nerves,
rendering the dissection both tedious and difficult.
The Axillary Vein will be found lying anterior
to the artery, that is, nearer the integuments. It
seems to be a continuation of the basilic vein, which
runs along the inside of the arm quite superficial, and
of the two or three venae satellites, or veins which
accompany the brachial artery. The axillary vein
receives branches corresponding to the ramifications
of the artery. Passing under the clavicle, it becomes
the subclavian vein, and runs over the first rib, and
before the anterior scalenus muscle into the thorax.
Deeper seated, and immediately behind the axillary
vein, lies the Axillary Artery. It is seen coming
from under the clavicle; from under the arch formed
by the pectoralis minor, it comes over the middle of
the first rib, and between the anterior, and middle
226 LONDON DISSECTOR, OR
scaleni muscles. In the axilla it is surrounded by the
meshes of the nerves, and runs along the inferior edge
of the coraco-brachialis muscle; when it has passed
the anterior edge of the pectoralis major, it assumes
the name of the Brachial Artery.
The branches of the axillary artery are,
1. A. Mammaria Externa; called also, A. Tho-
racicae Externas. — The external mammary artery
consists of three or four branches which run down-
wards and forwards obliquely over the chest. These
branches sometimes come off separately from the
axillary artery, at other times by one or two common
trunks, which subdivide. They supply the pectoral
muscles and mamma. Some of their branches pass
to the muscles of the shoulder, to the side of the chest,
and to the muscles on the inside of the scapula.
2. A. Scapularis Interna, Supra-scapularis, or
Dorsalis Scapula 1 , is sent off from the back-part of
the axillary artery. It runs across the bottom of the
neck towards the root of the coracoid process, and
passes through the semilunar notch in the superior
costa of the scapula; it supplies the supra-spinatus
muscle, and then passes under the acromion, to ramify
on the muscles below the spine of the scapula. It is
generally a branch of the A. Thyroidea Inferior, and
is then named A. Transversalis Humeri.
3. A. Scapularis Externa, Infra-scapularis,
or Thoracica Posterior, arises from the under and
back part of the axillary artery, attaches itself to the
inferior costa of the scapula, where it splits into two
great branches: 1. A large branch, which passes to
the outer surface of the scapula below the spine, and
has its principal ramifications close upon the bone.
2. The other branch (which is larger) passes to the
inner surface of the scapula, supplies the subscapu-
laris, and sends branches downwards to the muscles
of the back and loins.
guide to anatomy. 227
4. Arteria Circumflexa Humeri Posterior,
Humeralis, or Reflexa Articularis, arises from the
lower and fore part of the axillary artery, and runs
backwards close to the bone, surrounds its neck, and
is lost on the inner surface of the deltoid; it gives
also twigs to the joint and neighbouring muscles.
5. A. Circumflexa Anterior is a much smaller
artery, often a branch of the circumflexa posterior;
it encircles the neck of the bone on its fore-part, and
is lost on the inner surface of the deltoides, where it
inosculates with the posterior circumflex artery.
The Great Brachial Nerves accompany the
subclavian artery over the first rib. In the axilla
they are united by numerous cross branches, forming
the Axillary or Brachial Plexus, which is continued
from the clavicle as low as the edge of the tendon of
the latissimus dorsi, and which surrounds the axillary
artery with its meshes.
From the axillary plexus seven nerves pass off.
1. Nervus Supra-scapularis, Scapularis Exter-
nus, Scapularis. — This nerve comes off from the
upper edge of the plexus; it crosses the axilla at the
highest part, runs towards the superior costa of the
scapula, accompanies the ext^nal scapular artery
through the semilunar notch, and supplies the mus-
cles on the posterior surface of the scapula.
2. N. Circumflexus, Articularis, Axillaris, or
Humeralis, lies deep: it passes from the back part of
the plexus, goes backwards round the neck of the
bone, accompanying the posterior circumflex artery,
and is distributed to the musculus deltoides, and the
muscles on the outside of the arm. Small nerves
also pass from the axillary plexus to the subscapular
muscle, the teres major, latissimus dorsi, and pecto-
ral muscles.
3. The External Cutaneous Nerve, or Nervus-
Musculo-cutaneus.
228 LONDON DISSECTOR, OR
4. The Radial Nerve.
5. The Ulnar Nerve.
6. The Muscular or Spiral Nerve.
7. The Internal Cutaneous Nerve.
These five nerves will be described in the dissec-
tion of the arm and fore-arm.
DISSECTION OF THE POSTERIOR MEDIAS-
TINUM,* AND OF THE NERVES AND
VESSELS WHICH HAVE THEIR
COURSE THROUGH THE
THORAX.
Course of the Phrenic Nerve through the tho-
rax. — On each side this nerve is seen entering the
thorax betwixt the subclavian artery and subclavian
vein; it then proceeds downwards and forwards before
the root of the lungs, and on the outside of the peri-
cardium, betwixt that bag and the pleura; and is lost
on the diaphragm. The left phrenic nerve has a
somewhat longer cpjurse than the nerve of the right
side, as it passes over the pericardium, where that
bag covers the apex of the heart. This nerve is
accompanied by one artery and two veins; some
twigs pass from the phrenic nerve into the abdomen,
to the liver, &c.
Behind the arch of the aorta and great vessels pass-
ing from the heart, is seen the Trachea. It enters
the thorax between the two pleura), and, opposite the
third or fourth dorsal vertebra, bifurcates into two
parts: one of which passes toward the right, the
other toward the left, to enter the lung of each side.
* By Posterior Mediastinum is designed that part of the mediastinum
situated behind the root of the lungs.
GUIDE TO ANATOMY. 229
By folding back the lungs towards the left side of
the chest, we expose the pleura reflected from the
under surface of the root of the lungs to the spine and
ribs. A triangular space is formed betwixt the two
pleurae and the bodies of the dorsal vertebrae; this
space or cavity is named the cavity of the posterior
mediastinum. It contains many important parts, and
must therefore be carefully dissected.
But first let us attend to the course of the intercos-
tal, or great sympathetic nerve, which is seen running
by the side of the spine.
The Intercostal Nerve, where it enters the
thorax, is situated behind the great vessels; close upon
the articulation of the first rib with the body of the
first dorsal vertebra, it forms a ganglion, a twig ot
which fairly encircles the subclavian artery, while
other filaments are entwisted round the root of
vertebral artery. The intercostal nerve then descend^
along the thorax; it lies upon the heads of the rib-,
where they are articulated with the vertebrae; it re-
ceives additional branches from all the dorsal nerve=.
and in each intercostal space it forms a ganglion. T
nerve may be dissected with greater facility when the
lungs are removed, and the ribs sawed ofFnear the spine .
which will enable the dissector to trace its branches
more fully. It lies behind the pleura, but is seen
through it; it passes into the abdomen by the side of
the spine, running through the fibres of the small
muscle of the diaphragm.
BRANCHES OF THE INTERCOSTAL IN THE THORAX.
The Anterior Intercostal, or Splanchnic
Nerve, should be attended to. It is formed by three
or four twigs, which come off from the intercostal
betwixt the fourth and eighth dorsal vertebrae; these
20
230 LONDON DISSECTOR, OR
twigs, passing forward on the bodies of the vertebrae,
unite to form the splanchnic nerve, which may be
traced entering the abdomen, betwixt the crura of the
small muscle of the diaphragm.
From the intercostal also, twigs are given off, which
assist the branches of the par vagum, and of the dorsal
nerves, in forming several plexuses to supply the vis-
cera of the thorax.
The right intercostal nerve lies under the pleura
by the right side of the spine. Still nearer the middle
of the spine, you see the Vena Azygos. In dissect-
ing it is found situated betwixt the right intercostal
nerve and the aorta; it begins below from ramifications
of the lumbar arteries, which pierce the small muscle
of the diaphragm. This vein ascends along the spine,
receiving veins from each of the intercostal spaces of
the right side, and, about the middle of the back, it
receives a considerable trunk, which comes from un-
der the aorta, and returns the blood from the left side of
the thorax. At the fourth dorsal vertebra, the vena
azygos leaves the spine; it makes a curve forward,
and empties its blood into the back part of the vena
cava superior, immediately before that vein enters the
pericardium.
Descending through the posterior mediastinum, will
be also found the Aorta. This great artery, having
formed its arch, comes in contact with the third dorsal
vertebra, and is now called the Descending Aorta, or
Thoracic Aorta. It descends along the bodies of the
dorsal vertebrae, rather on their left side; it lies be-
hind the oesophagus, and passes betwixt the crura of
the diaphragm into the abdomen.
Branches of the Aorta in the Thorax.
1. A. Intercostales Inferiores. — The arteries
which supply the three or four superior intercostal
spaces, generally come off in one common trunk, which
afterwards subdivides.
GUIDE TO ANATOMY. 231
The Intercostalis Superior, on the right side, is
mostly sent off by the subclavian; on the left side, by
the aorta.
The Inferior Intercostals are eight or nine in num-
ber on each side of the thorax; they come off sepa-
rately from the side or back part of the aorta, and
seem to tie that great artery to the spine. Each in-
tercostal artery passes immediately into the interval
betwixt two ribs, and there subdivides into,
(1.) A branch which perforates between the heads
of the ribs to the muscles of the back; this branch also
gives twigs which enter the spinal canal.
(2.) The continued trunk of the artery runs for-
wards, in the interval of the two ribs, giving many
branches to the intercostal muscles. When it reaches
the anterior part of the thorax, it is lost in the mus-
cles.
Each intercostal artery is accompanied by one or
two veins, branches of the vena azygos, and by an
intercostal or dorsal nerve.
2. A. Bro>xhiales are two, sometimes three,
small twigs of the aorta, one of which passes to the
lungs on each side; they sometimes arise from the
subclavian and superior intercostal.
3. Small arteries pass forwards from the aorta on
the oesophagus, named A. (Esophageae; others run to
the pericardium and pleura.
The dissector also finds in the posterior mediasti-
num the Thoracic Duct. He must look for it behind
the oesophagus, betwixt the vena azygos and aorta; it
is collapsed, and appears like cellular membrane con-
densed, and can only be distinguished when inflated
or injected; it was seen in the abdomen close to the
aorta, and passing into the thorax between the crura
of the diaphragm. It ascends along the posterior
mediastinum, and, about the fourth dorsal vertebra,
passes obliquely to the left side, behind the aorta
232 LONDON DISSECTOR, OR
descendens, and behind the great arch of the aorta,
until it reaches the left carotid artery. It runs behind
this artery, and behind the left internal jugular vein;
and, after forming a circular turn or arch (the con-
vexity of which is turned upwards,) it descends, and
enters the left subclavian vein at the point where that
vein is joined by the left internal jugular. In its
course along the spine, the thoracic duct frequently
splits into two branches, which re-unite. The absorb-
ents of the right superior extremity, and of the right
side of the head and thorax, usually form a trunk,
which enters the right subclavian vein.
The (Esophagus is also situated betwixt the layers
of the posterior mediastinum. It lies immediately
before the aorta, but rather towards its left side; it is
seen descending from the neck behind the trachea; it
passes through an opening in the lesser muscle of the
diaphragm, and immediately expands into the stomach.
Behind the trachea and vessels going to the lungs,
and on the fore part of the oesophagus, Ave meet with
a congeries of lymphatic glands.
COURSE OF THE PAR VAGUM, OR EIGHTH PAIR OF
NERVES, IN THE THORAX.
From the neck, the par vagum passes betwixt the
subclavian vein and artery into the thorax; it imme-
diately sends off a large branch, the Recurrent
Nerve, back into the neck. On the right side, this
branch twists round under the arteria innominata; on
the left side, under the arch of the aorta, it ascends
behind the carotid, and lodges itself betwixt the tra-
chea and oesophagus, to both of which it gives branches.
The par vagum, having given off the recurrent,
descends by the side of the trachea, and behind the
root of the lungs. It here sends off numerous fila-
ments to the lungs, winch, uniting with twigs from
GUIDE TO ANATOMY. 2oo
the great sympathetic, form the Anterior and Pos-
terior Pulmonary Plexuses; these plexuses lie on
the anterior and posterior surfaces of the root of the
lungs. Other twigs of the par vagum pass, to form
the inferior Cardiac Plexus about the pericardium.
The trunk of the eighth pair soon reaches the oeso-
phagus; the left par vagum runs on the fore part of the
oesophagus, the right nerve on its back part. Here
they split into several branches, which unite again,
and form a Plexus. This plexus is called the (Esopha-
geal. The two nerves continue their course along the
oesophagus, and pass with it through the diaphragm,
to ramify on the stomach, and form the stomachic
plexus.
The twelve dorsal or intercostal nerves are also
seen in this dissection, emerging from the spinal canal,
between the bodies of the vertebrae, and supplying
the intercostal muscles, &c.
OF THE VESSELS AND NERVES]
OF THE FACE.
arteries.
The A. Maxillaris Externa, the third branch
of the carotid, comes from the neck over the lower
jaw at the anterior edge of the masseter. It then runs
under the depressor anguli oris, passes towards the
angle of the mouth, and is often much contorted. Here
it is named the A. Facialis or Angularis. It ascends
by the side of the nose, and, reaching the inner angle
of the eye, is lost on the muscles situated there, inos-
culating freely with the temporal, internal maxillary,
and ophthalmic arteries. In this course it gives off
many branches: 1. Twigs to the masseter, depressor
234 LONDON DISSECTOR, OR
anguli oris, and chin; 2. A. Coronaria Labiorum.
This artery is very much contorted. — At the angular
commissure of the lips, it divides itself into two
branches, which run along the superior and inferior
portions of the orbicularis oris, and join the same
branches of the other side. 3. While the facial
artery ascends by the side of the nose, it gives off the
external nasal arteries to the outside of the nose, and
the A. Buccales to the cheek.
The External Carotid is found ascending behind
the parotid gland. It perforates the gland at its upper
part, ascends over the zygomatic process immediately
before the ear, and divides into the anterior, middle,
and posterior temporal arteries, which ramify over
the side of the head, giving also branches to the fore-
head and occiput.
But the carotid, while it lies embedded under the
parotid, sends several twigs to the substance of that
gland, and a considerable artery which passes for-
wards, and, ramifying on the side of the face, is named
A. Transversalis Faciei. At this point also, the
carotid sends off a large artery, the A. Maxillaris
Interna. As many branches of this artery are met
with in the dissection of the face, it is proper to give
a view of its distribution.
The Interna] Maxillary passes behind the condyloid
process of the lower jaw: it directs its course towards
the bottom of the orbit of the eye; and it is at this point
that it sends off its numerous branches. (1.) Arteria
Media DuRiE Matris (or Meningea spheno-spinalis
or spinosa) passes through the spinal hole of the sphe-
noid bone into the cranium, and is distributed to the
dura mater. (2.) A. Maxillaris Inferior, vel
Dentalis Inferior, runs downwards, enters the foramen
at the root of the ascending processes of the lower
jaw; then passes through the canal of the lower jaw,
supplying the teeth and sockets, and emerges by the
GUIDE TO ANATOMY. 235
foramen mentale, to be distributed to the chin. It'is
accompanied by a nerve and one or two veins. (3.)
A. Pterygoideae and A. Temporales Profunda?, are
small branches of the internal maxillary which pass
to the pterygoid muscles, and to the inner part of the
temporal muscle. (4.) A. Pharyngeal, branches to the
pharynx, palate, and base of the skull. (5.) A. Are-
olaris, which gives branches to the teeth of the upper
jaw, and to the jaw-bone itself. (6.) A Branch through
the foramen spheno-palatinum to the nose; and, (7.)
An Artery through the palato-maxillary canal to the
palate.
The continued trunk of the internal maxillary enters
the orbit by the spheno-maxillary slit. It sends off a
branch which runs along the inner side of the orbit,
and passes out at the inner canthus of the eye on the
forehead. The artery itself runs along the bottom of
the orbit in a canal on the upper part of the great
tuberosity of the os maxillare superius, and emerges
by the foramen infra-orbitarium on the face; hence it
is termed A. Infra-Orbitaria, and is distributed to the
cheek and side of the nose.
The Frontal Artery is also seen in the dissection
of the face, passing from the orbit through the foramen
supra-orbitarium to be distributed to the forehead.
This artery is sent off from the ophthalmic artery,
which is a branch of the internal carotid.
If the face be injected, a remarkable anastomosis
of arteries will be observed at the inner angle of the
eye.
VEINS.
The veins of the face are numerous, and pass into
the external and internal jugular veins.
23Q LONDON DISSECTOR, OR
NERVES.
I. The Portio Dura of the seventh pair, Nervus
Communicans Faciei, or Facial Nerve, after its course
through the temporal bone in the aqueduct of Fallopius,
comes out by the foramen stylo-mastoideum. It
immediately gives off branches to the neighboring
parts, as behind the ear. It then passes through the
substance of the parotid gland, and emerges on the
face in three great branches, which have frequent
mutual communications: this division of the nerve is
called Pes Anserinus.
(1.) The ascending branch ramifies on the temple
and forehead.
(2.) The middle branch sends its ramifications over
the side of the face, the proper Facial Nerves.
(3.) The descending branch sends its twigs along
the chin, down upon the neck, and backwards upon
the occiput.
2. The Superior Cervical Nerves send off
several branches, which ramify on the side of the face
and head, and communicate freely with the branches
of the portio dura.
As, in the course of this dissection, we meet with
many twigs of the second and third branches of the
fifth pair of nerves, it will be advisable here to describe
these nerves.
3. Nervus Maxillaris Superior, or Second
Branch of the Fifth Pair. The superior maxillary
nerve, having left the cranium by the foramen rotun-
dum of the sphenoid bone, emerges behind the antrum
maxillare, at the lower back part of the orbit, and at
the root of the pterygoid process of the sphenoid bone.
It immediately sends out branches: 1 . A small branch
which passes through the spheno-maxillary slit to the
periosteum and fat of the orbit. 2. The largest
branch is the Infra-Orbitary Nerve. It enters
GUIDE TO ANATOMY. 237
the channel in the top of the antrum maxillare, accom-
panying the infra-orbitary artery, comes out at the
foramen infra-orbitarium, and is widely distributed to
the cheek, under lip, and outside of the nose, commu-
nicating with ramifications of the portio dura. 3.
Branches to the temporal muscle, os mala?, &c. 4.
Other branches form a small ganglion at the root of
the orbit, which sends twigs, named the superior Nasal
Nerves, through the foramen spheno-palatinum to the
nose. 5. The Vidian Nerve, which enters the fora-
men pterygoideum, and passes again into the cranium,
to connect itself with the portio dura. 6. The Pala-
tine Nerve, which runs through the palato-maxillary
canal to the palate. 7. Twigs which supply the gums
and alveoli of the upper jaw.
4. Nervus Maxillaris Inferior, or Third
Branch of the Fifth Pair. The inferior maxillary
nerve leaves the cranium by the foramen ovale of the
sphenoid bone. It has its course downwards and out-
wards; and, having given twigs to the parts near which
it passes, as the masseter, pterygoid, and temporal
muscles, it divides at the angle of the lower jaw into
two branches. 1. The Nervus Dentalis Inferior
enters the foramen at the angle of the lower jaw;
accompanies the inferior dental artery along the canal
in that bone, giving nerves to the teeth; emerges by
the foramen mentale, and is distributed to the chin.
2. The Nervus Gustatorius, vel Lingualis, passes to
the tongue. It was seen in the dissection of the neck
lying close upon the lower jaw-bone, below the infe-
rior edge of the pterygoideus internus, and above the
superior fibres of the mylo-hyoideus. It supplies the
substance of the tongue, and the salivary glands situ-
ated at the root of the tongue.
This nerve receives the chorda tympani, a small
twig which comes from the seventh pair through the
slit in the articulating cavity of the temporal bone.
238 LONDON DISSECTOR, OR
5. In the dissection of the face, we also meet with
the Frontal Nerve; which comes from the first
branch of the fifth pair, and which is seen accompany-
ing the frontal artery through the foramen supra-orbi-
tarium. It is distributed to the forehead.
OF THE VESSELS AND NERVES
MET WITH IN THE ORBIT
OF THE EYE.
ARTERIES.
The Ophthalmic, or Ocular Artery, is a branch
of the internal carotid. It enters the orbit from the
basis of the cranium by the foramen opticum. It gives
branches to the lachrymal gland, fat, muscles, and
globe of the eye. One twig, named the A. Centralis
Retinas, enters the substance of the optic nerve, and
is continued on to the retina; — twigs also pass to the
eye-lids, and to the inner angle of the eye. The Ar-
teria Frontalis is a branch of this artery; it is seen
running towards the supra-orbitary notch or foramen,
and is distributed to the forehead.
The Infra-Orbitary Artery is found in the
lower part of the orbit; it is the continued trunk of
the internal maxillary, entering the orbit by the sphe-
no-maxillary slit. It is seen passing along the canal
in the upper part of the great tuberosity of the os
maxillare superius, and emerges on the face by the
infra-orbitary hole.
VEINS.
These correspond with the arteries; they discharge
their blood partly into the branches of the external
jugular vein near the forehead and temples, and partly
into the internal jugular.
GUIDE TO ANATOMY. 239
NERVES.
1 . The Optic Nerve is seen coming through the
foramen opticum, and entering the back part of the
globe of the eye, to form the retina.
2. The Nerve of the Third Pair, Motor Oculi,
having entered the orbit through the superior orbi-
tary fissure, or foramen lacerum, is divided into four
branches.
(1.) The first runs upwards, and subdivides into
two nerves, of which one supplies the levator oculi,
and the other the levator palpebral superioris.
(2.) The second branch goes to the depressor oculi,
and is short.
(3.) The third branch supplies the obliquus inferior,
and also gives off a twig, which assists in forming the
lenticular ganglion.
(4.) The fourth branch supplies the adductor oculi.
3. The Nerve of the Fourth Pair, N. Patheticus,
or Trochlearis, enters the orbit by the superior orbi-
tary fissure, and runs to the obliquus superior.
4. The first branch of the Nerve of the Fifth Pair,
named Ophthalmic, or Orbitary, enters the orbit by
the superior orbitary fissure, and divides into three
branches.
(1.) The Frontal, Supra-orbitary, or Superciliary
Nerve, accompanies the frontal artery along the upper
part of the orbit, close to the bone; and having passed
through the supra-orbitary notch, is distributed to the
forehead.
(2.) The Nasal Nerve, or inner branch, runs to-
wards the nose, and is distributed to the inner side of
the orbit, and to the nose.
(3.) The Temporal or Lachrymal Branch supplies
the lachrymal gland, and the parts at the outer side of
the orbit.
The Lenticular Ganglion is a small ganglion,
240 LONDON DISSECTOR, OR
situated within the orbit, formed by short branches of
the ophthalmic nerve, and by a twig of the third pair.
It sends off delicate nerves which run along the sides
of the optic nerve, and pierce the coats of the eye.
5. The second branch of the Fifth Pair, called the
Superior Maxillary Nerve, sends off a branch
through the bony canal in the bottom of the orbit.
This is the Infra-orbitary Nerve. It accompanies
the artery of the same name, and emerges on the face
by the infra-orbitary hole.
6. The Trunk of the Sixth Pair of Nerves passes
through the superior orbitary fissure to the abductor
oculi.
These delicate nerves are surrounded by the adi-
pose substance found in the orbit, and require to be
dissected with the utmost care.
DISSECTION OF THE CUTANEOUS
VESSELS AND NERVES OF THE
SHOULDER AND ARM.
In removing the integuments, we meet with several
cutaneous veins and nerves.
The cutaneous veins* of the upper extremity are
the following.
1. The Basilic Vein is seen arising from a small
vein on the outside of the little finger, named Salva-
tella. It then runs along the inside of the fore arm
near the ulna, receiving the internal and external ulnar
veins from the anterior and posterior surface of the
fascia. It passes over the fold of the arm near the
inner condyle of the humerus; here it is superficial.
* The veins are described from their origin in the fore arm, for the
sake of perspicuity; they ramify above the fascia of the fore arm.
GUIDE TO ANATOMY. 241
Tt ascends along the arm, becoming more deeply seat-
ed, and included in the sheath which invests the
brachial artery. As it approaches the neck of the
humerus, it sinks deep betwixt the folds of the arm-
pit, and terminates in the axillary vein, which maybe
considered as a continuation of the basilic vein. It
communicates with the deeper-seated veins, and
receives numerous branches from the muscles.
2. The Cephalic Vein begins on the back of the
hand, between the thumb and metacarpal bone of the
fore-finger, by a small vein, named Cephalica Pollicis.
It runs along the radius between the muscles and
integuments, receiving the internal and external radial
veins. It passes over the bend of the arm near the
external condyle, and ascends along the outside of the
arm near the outer edge of the biceps flexor cubiti.
It then runs betwixt the edge of the deltoid and pec-
toral muscles, dips down under the clavicle, and enters
the subclavian vein. In all this course, the cephalic
vein receives branches.
3. The Median Vein. Several veins are seen
running along the middle of the anterior part of the
fore-arm. The trunk formed by these veins is called
the Mediana Major. It ascends on the fiat part of the
fore arm, betwixt the basilic and cephalic veins, and
bifurcates at the fold of the arm into two branches:
1 . The Mediana Basilica, passing off obliquely to join
the basilic vein; 2. The Mediana Cephalica, which
joins the cephalic.
The cutaneous nerves of the arm are seen ramifying
above the muscles; they consist of,
1 . The Internal Cutaneous Nerve, a branch of the
axillary plexus. It is seen accompanying the basilic
vein, and twisting its fibres over it. It descends along
the inside of the arm, crosses over the fore part of
the elbow-joint, and, in the dissection of the fore arm,
will be seen dividing itself into twigs, which ramify
21
242 LONDON DISSECTOR, OR
between the fascia and integuments, and are distri-
buted to the inside of the fore arm and wrist.
2. The upper part of the arm receives cutaneous
nerves from the branches of the dorsal nerves, which
come out of the thorax between the ribs.
3. The shoulder and back part of the scapula
receive twigs from the cervical nerves.
4. The external cutaneous, ulnar, and spiral nerves,
also send twigs to the integuments of the arm and
lore arm.
The relative situation of the vessels at the bend of
the arm should be well attended to. The cutaneous
veins situated here vary much in size. The vena
basilica is seen running over the fore part of the bend
of the arm near the inner condyle, the vena cephalica
situated near the outer condyle; and each of these
veins receives a branch passing obliquely from the
vena mediana major. These vessels lie above the
fascia, while the brachial artery lies deep beneath the
fascia, in a hollow resembling that of the axilla. It
descends over the joint near the inner condyle, on the
inside of the tendon of the biceps flexor cubiti, and
under the aponeurosis sent off from that muscle to the
common fascia of the fore arm. It lies embedded in
cellular substance, betwixt the pronator teres and
flexor muscles of the wrist and fingers on one side,
and the supinator longus and extensor muscles on the
other. In this hollow it divides into the radial, ulnar,
and interosseal arteries. The artery is accompanied
by two veins, and on its inner side runs the radial
nerve.
GUIDE TO ANATOMY. 243
OF THE VESSELS AND NERVES OF
THE SUPERIOR EXTREMITY.
ARTERIES.
The subclavian and axillary arteries have already
been described.
The Brachial Artery may be said to have its
course along the inside of the arm. Having- left the
axilla, it runs along the inferior edge of the coraco-
brachialis. Rather higher up than the middle of the
os humeri, it crosses over the tendinous insertion of
that muscle, being here situated between the belly of
the biceps flexor cubiti,and the superior fibres of the
brachialis externus. The artery then passes behind
the inner edge of the biceps flexor cubiti, descending
betwixt that muscle and the fibres of the brachialis
internus. In dissecting this vessel, we find it invested
by a fascia or sheath, formed by cellular membrane
and some tendinous fibres. This fascia may be traced
extending from the internal intermuscular ligament.
It covers the brachial artery and radial nerve; and the
great basilic vein, as it enters into the axilla, is found
lying in the fore and inner part of this sheath. It
supports and connects these vessels. On dissecting
this fascia, we find, close to the margin of the coraco-
brachialis and biceps flexor cubiti, the great radial
nerve; under it the brachial artery; and, more super-
ficially seated, the venae comites and the vena basilica.
As the artery approaches the lower extremity of the
os humeri, it inclines forwards toward the fold of the
arm, and dives beneath the aponeurosis which arises
from the inside of the tendon of the biceps flexor
cubiti. Its situation at the fold of the arm has been
described.
244 LONDON DISSECTOR, OR
BRANCHES OF THE BRACHIAL ARTERY.
1. A. Profunda Humeri Superior, or Muscu-
laris Superior, is sent off from the inner side of the
brachial artery, immediately where it has left the fold
of the arm-pit. It passes downwards and backwards
round the os humeri, and is accompanied by the
muscular or spiral nerve. It passes betwixt the
brachialis externus and short head of the triceps
extensor cubiti. Here it lies deep among the muscles,
and divides into two branches. One accompanying
the nerve spreads its ramifications over the outer
condyle, and anastomoses with the arteries below the
elbow. The other branch is distributed along the
inside of the arm, and about the inner condyle.
2. A. Profunda Humeri Inferior, vel Minor,
or Muscularis Inferior, is smaller than the last, and is
sent off from the brachial artery about two inches
lower down. It descends among the muscles on the
inside of the arm, and is lost about the inner condj^le.
3. The anastomosing or collateral arteries are as
follows.
(1.) The Ramus Anastomoticus Major passes from
the inside of the brachial artery, about two or three
inches above the inner condyle. It is distributed
about the condyle; and its principal branch accom-
panies the ulnar nerve in the groove betwixt the
olecranon and inner condyle, to anastomose with the
recurrent branches of the arteries of the fore-arm.
(2.) There are two or three more anastomosing
branches, which are sent off from the brachial artery,
and ramify over the anterior and posterior surfaces of
the two condyles.
4. Small branches to the muscles of the arm.
The Brachial Artery, where it lies deep under the
aponeurosis of the biceps, divides into three branches.
1. The radial; 2. The ulnar; and, 3. The interosse-
GUIDE TO ANATOMY. 245
ous artery. The last two generally come off by one
trunk, which subdivides.
1. Arteria Radialis, the radial artery, is smaller
than the ulnar, and in its course more superficial. It
leaves the ulnar artery, and inclines towards the radial
or outer edge of the fore-arm. At first it lies betwixt
the pronator teres and supinator longus. It then
descends close along the inner edge of the supinator
longus, and about the middle of the fore-arm passes
over the insertion of the pronator teres. It then holds
its course betwixt the supinator longus and flexor
carpi radialis, and is accompanied by a branch of the
muscular or spiral nerve. In this situation the artery
continues its course along the radius, till, reaching the
lower extremity of that bone, it divides into two
branches.
(1.) Ramus Volaris, A. Suterficialis Vol.e, is
by much the smaller of the two branches. It passes
into the muscular mass which forms the ball of the
thumb, and spreads its ramifications on the palmar
fascia, the annular ligament of the wrist, and muscles
of the thumb, anastomosing with the ramifications of
the superficial palmar arch.
(2.) The trunk of the radial artery crosses over
the lower extremity of the radius to the back of the
hand. It passes under the extensors of the thumb,
over the os scaphoides and the junction of the os tra-
pezium and trapezoides, and, arriving at the space
betwixt the bases of the metacarpal bones of the
thumb and fore-finger, plunges into the palm of the
hand.
The branches of the radial artery, in its course
along the fore-arm, are the following.
(1.) The recurrent artery is sent off from the radial
immediately after it leaves the ulnar artery, and is
distributed over the anterior part of the outercondvle,
21*
246 LONDON DISSECTOR, OR
where it anastomoses with branches of the brachial
artery.
(2.) Small arteries to the muscles of the fore-arm,
and to the radius.
(.3.) A branch leaves the artery immediately after
it has turned over the edge of the radius, and, ramify-
ing on the back of the hand, is named Dorsalis Carpi.
(4.) Small vessels are sent off to the back part of
the thumb, named A. Dorsales Pollicis.
Having reached the palm of the hand, the radial
artery divides into two branches.
(1.) A. Pollicis, which sends two or three arteries
along the anterior part of the thumb, and also often
gives off a twig, the A. Radialis Indicis, which passes
along the outer edge of the fore-finger, and inosculates
with a branch of the ulnar artery.
(2.) The trunk of the radial artery forms the
Deep-seated Palmar Arch. From the root of the
thumb, it passes across the metacarpal bones near
their bases, and terminates at the metacarpal bone of
the little finger, inosculating with a branch of the
ulnar artery. This arch lies deep, close to the bones.
It supplies the interosseous muscles and deep-seated
parts of the palm, and some of its branches pass
betwixt the metacarpal bones to the back of the
hand.
2. Arteria Ulnaris, or Cubitalis. The ulnar
artery is the largest branch of the brachial, and gene-
rally gives off the interosseous artery. It takes its
course deep among the muscles on the inside of the
fore-arm. It is seen passing under the pronator teres,
flexor carpi radialis, palmaris longus, and flexor sub-
limis perforatus, but over the flexor profundus perfo-
rans. It descends in the connecting cellular membrane
between the flexor sublimis and profundus; but about
the middle of the fore-arm, it emerges from these
muscles, and appears at the ulnar edge of the arm,
GUIDE TO ANATOMY. 247
betwixt the flexor sublimis and flexor carpi ulnaris.
It passes over the annular ligament of the wrist, which
binds down the flexor tendons of the fingers, but is
covered by the fascia which ties down the tendon of
the flexor carpi ulnaris. It passes under the palmar
aponeurosis, on the inside of the os pisiforme, reaches
the base of the metacarpal bone of the little finger,
and begins to form the Superficial Palmar Arch.
This arch lies above the tendons of the flexor sublimis
perforatus, immediately beneath the palmar aponeu-
rosis. It crosses the metacarpal bones betwixt their
bases and the middle of their bodies. It begins at the
root of the little finger, and terminates at the root of
the thumb, in inosculations with the branches of the
radial artery. The convex side of the arch is turned
towards the fingers, and sends off five branches.
(1.) A branch to the muscles and inner edge of the
little finger.
(2.) Ramus digitalis primus, or the first digital ar-
tery, which runs along the space betwixt the two last
metacarpal bones, and bifurcates into two branches,
one to the outer side of the little finger, and the other
to the inner side of the ring finger.
(3.) The second digital artery, which bifurcates in
a similar manner, and supplies the outer edge of the
ring finger, and the inner side of the middle finger.
(4.) The third digital artery, which is distributed
to the outer edge of the middle finger, and to the inner
side of the fore finger.
(5.) The ramus pollicis ulnaris is the last branch
of the ulnar artery, and is sent to the muscles of the
thumb.
From the concavity of the arch are sent off the in-
terosseous arteries of the palm, small twigs which
supply the deep seated parts, and perforate betwixt
the metacarpal bones to the back of the hand.
248 LONDON DISSECTOR, OR
The branches of the ulnar artery, in its course along
the fore-arm and wrist, are the following.
(1.) The Recurrent Arteries are two in number.
They are sent off from the ulnar artery immediately
below the elbow, sometimes in one common branch,
which subdivides. The anterior recurrent runs over N
the fore part of the inner condyle; the posterior re-
current passes over the back part. These arteries
inosculate with branches of the brachial.
(2.) Twigs to the muscles of the fore-arm.
(3). A. Dorsalis Carpi is sent off from the ulnar
artery a little above the wrist to the back of the hand.
Twigs are also given off to the annular ligament and
neighboring parts.
(4.) A. Palmaris Profunda is sent off from the
ulnar artery, where it descends on the inside of the os
pisiforme. It passes into the flesh at the root of the
little finger, and inosculates with the termination of
the deep seated palmar arch of the radial artery.
3. Arteria Interossea (or Interossea Communis.)
This artery is generally sent off from the ulnar. It
immediately divides into two branches:
(1.) The external or posterior interosseous artery
is the smaller branch. It passes through the upper
part of the interosseous ligament, to supply the mus-
cles on the posterior part of the fore arm. It sends
off the A. Recurrens Interossea, which ramifies on the
middle of the back part of the elbow joint.
(2.) The internal or anterior interosseous artery
descends close upon the middle of the interosseous
ligament, between the flexor longus pollicis and flexor
profundus perforans, giving twigs to the adjacent
muscles. Arriving at the upper edge of the pronator
quadratus, it perforates betwixt the radius and ulna
to the back part of the arm, and spreads its extreme
branches on the wrist and back of the hand.
GUIDE TO ANATOMY. 249
VEINS.
The cutaneous veins have been already described.
The brachial artery is accompanied by two veins,
named Venae Comites, or Satellites. These receive
branches corresponding to the ramifications of the
artery.
NERVES.
In the dissection of the axilla, we demonstrated the
great axillary plexus, and traced its first two branches,
the external scapular and circumflex nerves. The
distribution of the five remaining branches of the
plexus must now be described.
(3.) The External Cutaneous Nerve (Muscu-
lo-cutaneus, or Perforans Casserii) is the third branch
of the axillary plexus. It passes through the belly of
the coraco-brachialis muscle. After its passage, it
continues its course obliquely across the arm, betwixt
the Biceps flexor cubiti and the Brachialis internus.
It gives twigs to these muscles, and appears as a su-
perficial nerve on the edge of the supinator longus.
It runs over the outer condyle, and is distributed to
the integuments on the outside of the fore arm, and
back of the hand.
(4.) The Radial (or Median) Nerve accompanies
the brachial artery to the bend of the elbow, and is
contained in the same sheath as the artery. In its
passage down the arm, it lies before that vessel, but
at the elbow is situated on its inside. It gives off no
branches until it has sunk under the aponeurotic ex-
pansion of the biceps flexor. Here it distributes many
nerves to the muscles of the fore arm, to the pronator
teres, flexor carpi radialis, the flexors of the thumb
and fingers, and the pronator quadratus. The trunk
of the nerve perforates the pronator teres, passes be-
twixt the flexor digitorum sublimis and flexor profuu-
250 LONDON DISSECTOR, OR
dus, and continues its course betwixt these muscles
down to the wrist. Near the wrist it becomes more
superficial, lying amongst the tendons of the flexors,
and before it descends under the annular ligament,
sends a superficial branch to the integuments, and the
short muscles of the thumb. The nerve itself passes
with the flexor tendons of the fingers under the annu-
lar ligament of the wrist, emerges from these tendons,
and appears on their outside, near the root of the
thumb. It ramifies superficially in the hand, sending off
four branches. The first branch passes to the thumb;
the second to the side of the fore finger next the thumb;
the third divides into two nerves, of which one passes
to the inner side of the fore finger; the fourth also
subdivides into two, to the inside of the middle finger,
and outer side of the ring-finger. These nerves pass
before the flexor tendons, but behind the superficial
palmar arterial arch, to reach the fingers.
(5.) The Ulnar Nerve descends along the inside
of the arm. It is at first situated immediately under
the integuments, but below the middle of the arm is
tied down by the intermuscular ligament which passes
to the inner condyle of the humerus. The nerve be-
comes here more deeply seated; it runs between the
inner condyle in the hollow behind it and the olecra-
non, and in the flesh of the brachialis externus or third
head of the triceps extensor. After passing the con-
dyle, it continues its course betwixt the two heads of
the flexor carpi ulnaris, till it reaches the ulnar artery.
It then accompanies the ulnar artery, lying on its in-
side, and running along the fore arm between the
flexor ulnaris and flexor digitorum sublimis. It sends
twigs to the neighboring muscles, and, Avhen arrived
near the wrist, divides into two branches. 1. The
Smaller Branch, called Ramus Posticus, passes under
the tendon of the flexor carpi ulnaris, and over the
lower end of the ulna, to be distributed to the back
GUIDE TO ANATOMY. 251
of the hand, and of the little and ring-fingers. 2. The
continued trunk of the nerve passes, on the inside of
the ulnar artery, over the annular ligament of the
wrist It passes under the palmar aponeurosis, and
divides into three principal branches. The first sup-
plies the integuments and muscles on the ulnar edge
of the hand, and the inner side of the little finger.
The second is distributed to the outer side of the little
finger, and inner side of the ring-finger. The third
branch passes deep under the long tendons, accompa-
nies the deep seated palmar arch, and terminates in
the short muscles of the thumb and fore finger, com-
municating with the radial nerve.
(6.) The Muscular or Spiral Nerve (Radial
of some anatomists) passes from the axilla behind the
os humeri, making a spiral turn round the bone to
reach the outside of the arm. It first descends be-
tween the brachialis externus and short head of the
biceps extensor cubiti, accompanying the arteria pro-
funda humeri superior, and passing deep into the flesh
of the arm. Before it makes this turn, it gives branches
to the muscles, also a cutaneous branch, which de-
scends on the inside of the arm. From the back part
of the arm the great trunk of the nerve is reflected
spirally forwards. It is seen emerging betwixt the
supinator longus and brachialis internus, seated deep
and close to the bone. It descends betwixt these
muscles, keeping close to the edge of the supinator
longus. Immediately after passing the fold of the
arm, it sends off a nerve, which descends, superficial,
upon the radial edge of the fore arm, as far as the
wrist; and, at this point, the trunk of the muscular
nerve divides itself into two branches. The first, a
large branch, perforates the supinator brevis, and
supplies the extensor muscles of the hand and fingers.
The second branch accompanies the supinator longus
down the fore arm, and near the wrist turns under the
252 LONDON DISSECTOR. OR
tendon of that muscle, over the edge of the radius. It
then divides into several branches, which ramify on
the back of the wrist, thumb, and fore finger.
(7.) The Internal Cutaneous Nerve descends
superficial, along the inside of the arm and fore arm.
It was described among the cutaneous nerves of the
arm.
THE METHOD OF INJECTING THE
ARTERIES.
For the student, who desires to obtain a general
view of the arteries, it will be sufficient to inject them 4
from the arch of the aorta. For this purpose an
incision is to be made through the integuments along
the centre of the sternum throughout its whole length;
and the sternum divided longitudinally with a saw:
then lay open the thorax by bending back the two
portions of the sternum. An incision is then to be
made into the pericardium, and a small opening in the
ascending arch of the aorta; into which a pipe is to be
inserted and well secured.
For ordinary purposes, the injecting material may
consist of a strong heated solution of glue and colour-
ing matter.
When any particular part of the body alone is to be
injected, it is necessary to introduce the pipe into the
artery which supplies that particular member: thus,
if the head is to be injected, a pipe is to be introduced
into each common carotid, or, what is preferable, one
pipe with a bifurcation, and the vertebral arteries are
to be secured with a ligature. If an arm, insert the
pipe into the axillary artery; and for the lower extrem-
ity, fix the pipe in the common iliac artery according
to the side to be injected.
GUIDE TO ANATOMY. 253
METHOD OP INJECTING THE HEART AND GREAT
TESSELS.*
If we wish to inject the heart while it is in its
natural situation, we must sacrifice almost all the parts
of the chest to it; for it is a preparation so difficult to
make, and so expensive, that when we undertake it,
we must not hesitate to destroy the other parts. The
chest, for this purpose, is to be opened by cutting
through the sternum in its length, and by bending back
the lateral portions. The abdomen must also be
opened. The viscera are to be pulled down, so that
a large pipe may be put into the aorta, where it lies
between the crura of the diaphragm. Another pipe
is to be put into the vena cava ascendens, below the
liver.
We must then make a dissection on each side of
the neck, so as to expose the internal jugular veins,
into each of which, a pipe should be put. The caro-
tid and vertebral arteries are to be tied; so are the
subclavian: or perhaps it will be better to put tight
ligatures on the arms, just below the insertion of the
pectoralis major.
Previous to the injection of the veins, a quantity of
warm water should be thrown into them, so that it may
pass into the several cavities of the heart. The water is
then to be pressed out along with the coagula which
are generally found in the cavities of the heart. It is
principally upon this^being carefully done, that a good
injection of the heart depends.
When the parts are thoroughly heated, the red
injection should be thrown into the ascending aorta.
An assistant must now be ready to knead the injection
through the valves of the aorta; (but, if possible, a
probe should have been passed from the carotid,
* Shaw's Manual.
22
254 LONDON DISSECTOR, OR
before it was tied, to break down these valves;) when
the injection once passes the valves, it will quickly
distend the left ventricle, which must be supported by
the assistant, — the pericardium having been previously
opened. By a little pressure, the wax will pass into
the left auricle, and, from it, into the pulmonary veins.
It will be well to make a small puncture, with a lan-
cet, in the apex of the ventricle, to allow the escape
of any water or blood which may be still in this side
of the heart.
The right side of the heart may be filled with blue
or yellow injection from the pipes which have been
put into the several veins. It will be necessary to
make a puncture in the apex of the auricle, to permit
the exit of a certain quantity of water which will be
left in the heart, even though much care has been
taken to squeeze it all out previous to the injection.
Perhaps the vena azygos may be filled, with the
other veins; but if it be not, we must put a pipe into
it, and inject it separately.
The thoracic duct may also be injected. If sought
for in the abdomen, it will be discovered at the root
of the mesenteric vessels, or between the right cms
of the diaphragm and the aorta. It may be traced up
under the diaphragm, along with the aorta, and upon
its right side, close to the spine. As it generally lies
collapsed and undistinguishable, it may be raised by
blowing into some of the glands upon the root of the
mesentery, or into those upon the course of the exter-
nal iliac vessels, or even into those below Poupart's
ligament in the groin. It must be injected with a
different color from the veins, that it may not be con-
founded, in the thorax and at the root of the neck, with
their branches.
When the heart only is to be injected, we should
cut through the vessels going to the upper parts of the
body, as they are emerging from the thorax, and
remove the heart and lungs, by tearing them, along
GUIDE TO ANATOMY- 255
with the trachea and oesophagus, from the spine, —
making first an incision along the spine, to free the
intercostal arteries. We may then cut through the
aorta and vena cava, below the diaphragm: — a part of
the liver should be left attached to the vessels. It is
necessary to remove the heart in this manner, that
there may be no danger of cutting any of the great
vessels.
We should press out as much blood as possible from
the vessels, and then put a pipe into one of the pul-
monary veins, and another into the vena cava superior.
Having injected warm water by these tubes, to clear
the heart of the masses of coagulated blood which are
generally found in it after death, we must tie the lungs
at their roots, and the vena cava inferior, and all the
divided arteries, except the aorta, in which a pipe
must be put. If we throw red injection into the pul-
monary vein, it will fill the left auricle, left ventricle,
aorta, and coronary vessels; but during this part of the
injection, an assistant ought to hold and compress the
aorta immediately after its giving off the coronary
arteries, so as to press the injection on in them; but
as by this, the injection will be prevented from enter-
ing the aorta, it must be filled from the pipe which
was inserted into it. The injection escaping by the
intercostal arteries, may be stopped by an assistant
throwing cold water on the wax as it flows from the
vessels. The yellow injection thrown in by the vena
cava superior, will fill the right auricle, ventricle, and
pulmonary artery. The dissection required is simply
the removing of the soft parts from the injected ves-
sels.
256 LONDON DISSECTOR, OB
THE LYMPHATIC, OR ABSORBENT
SYSTEM.*
The lymphatic system consists of an elaborate set
of vessels, and of a number of glands distributed in
various parts in the course of these vessels.
The lymphatic vessels are tubes whose coats are per-
fectly pellucid, having a remarkable power of contrac-
tion. They are called lymphatics, or Ductus Aauosi,
from their transmitting a fluid colorless as water.
When distended with their fluids, they show that they
possess a character distinct from other vessels, being
irregularly distended, knotty, presenting sometimes
the appearance of a chain of beads, or little irregular
vesicles connected together. Everywhere throughout
the human body and the viscera, between the extreme
branches of the absorbent system and the trunk, gland-
ular bodies are interposed. These glands, though
differing m form, are generally of an oval shape, vary-
ing in size from the twentieth part of an inch to an
inch in diameter. Sometimes they are separate,
sometimes accumulated and clustered together. The
color of these bodies is various in the several parts
of the body; in the outer parts, as in the thigh, axilla,
&c, they are redder and stronger; but less so within
the abdomen and thorax. In children the lacteal and
lymphatic glands are exceedingly numerous, but they
shrink with advancing old age.
The function of these glands seems to be to check,
control and measure the flow of the absorbed fluids
into the mass of the blood, and perhaps also, to pro-
duce some modification in the fluid which is conveyed
to them. According to Bell, the lymphatics form a
system of absorbents which take up the fluids extra-
vasated, or secreted on the surfaces of membranes
and cavities. Thus they arise from the pores of the
* Bell's Anatomy.
GUIDE TO ANATOMY.
257
skin; from the surface of the cavities and viscera,
which are covered by the pleura and peritoneum; from
the cells of the interstitial and adipose membrane; from
all the ducts and cavities of the body. But whether
they are the only system of absorbents; whether they
carry away all the parts of the system, fluids and
solids, whether they absorb the muscles, membranes,
bones, tendons, &c, of which the solid body consists,
as well as the secreted fluids, are questions which we
must leave to the examination of physiologists.
OF THE COURSE OF THE LYM-
PHATICS.
The lymphatics, in their course and relation to the
fascia and muscles of the extremities, bear a great
analogy to the veins; for there are two sets or grand
divisions, — the deep lymphatics which accompany
the arteries in their branchings among the muscles;
and the superficial set which run a course external
to the fascia.
Of the foot, leg and thigh. — Even in the toes
the same distinction of the origins of the lymphatics
may be observed, as in the limb. For while a plexus
covers the toes superficially, and runs up upon the
foot with the veins, deeper branches accompany the
arteries on the side of the toes.
From the toes, dorsum, and edges of the foot, the
lymphatics ascend along the leg in four classes. 1 .
One takes a course from the root of the great toe and
inside of the foot, over the tendons of the great toe
and tibialis anticus tendon. It then passes on the
inside of the tendon of the tibialis anticus muscle,
and before the head of the tibia, following the prin-
22*
258 LONDON DISSECTOR, OR
cipal branch of the great saphena vein; and then
continues its course, in company with the saphena,
to the inside of the knee. 2. There is at the same
time a considerable number of lymphatics, taking
their origin from nearly the same place, viz. the
inside of the foot, and before the inner ankle; but they
take a different course on the leg from the last class;
for they pass behind the lower head of the tibia: they
attach themselves to some branch of the saphena vein,
and join the former set of vessels on the inside of the
knee. From this they ascend superficially above the
fascia to the glands of the groin. 3. From the out-
side of the foot there ascend several lymphatics; a
division of which passes before the outer ankle and
across the tibia to join the lymphatics, parasites of
the great saphena vein, and here they sometimes form
plexuses and Contortions; others turn in behind the
outer ankle, and join the branches accompanying the
lesser saphena vein.
The lymphatics which turn round behind the outer
ankle pass on the outside of the tendo Achillis; and
accompanying the lesser saphena vein, sink into the
popliteal hollow. Here they unite with the lymphatics
which have accompanied the several arteries of the
leg and foot, and particularly the posterior tibial
artery.
The deep lymphatics accompany the arteries, as
we have said; and to inject them we should look for
a very large vessel which is coming out from under
the plantar aponeurosis to rise behind the inner ankle.
Popliteal glands. — The glands of the ham-string
cavity are generally three in number, and very small.
They receive some of the lymphatics which pass with
the posterior tibial artery and with the lesser saphena.
From the popliteal glands there ascend two large
lymphatics, which accompany the popliteal artery
and venae comites, and ascend with the latter through
the adductor magnus to the fore part of the thigh.
GUIDE TO ANATOMY. 259
They run irregularly, or form a kind of net-work
round the great vessels. On the fore part of the thigh.
and still deep, they enter the lower and deep inguinal
glands.
Sometimes these deep lymphatics, instead of being
accumulated into larger trunks, divide into many
branches, and only unite in the glands of the groin.
Inguinal glands. — The inguinal glands are in
number from five to ten; they lie involved in cellular
membrane on the outside of the femoral ligament.
Some of them are superficial and moveable under the
integuments; some involved in the laminae of the fascia,
which descend from the abdominal muscles; some are
close on the femoral artery and vein, and under the
fascia. Nearer to the pubes may be observed a
division of these glands which belong to the lymphatics
of the penis, perineum, &c.
Lymphatics of the parts of generation in
both sexes. — From the penis there run backwards
two sets of lymphatics; superficial ones, which take
a course to the groin; and deeper ones, which take a
course along the arteries of the penis into the pelvis,
or under the arch of the pubis. The superficial lym-
phatics are the cutaneous vessels, and take their origin
from the prepuce.
In the external parts of the female there are also
two sets of lymphatics. Those near the clitoris pass
up in a direction to the ring; and those from the lower
part of the vulva and perineum to the glands of the
groin.
Lymphatics and glands within the ligament
of the thigh. — The vasa efferentia of the inguinal
glands are in number from two to six. The deep
lymphatics which accompany the femoral vein and
artery, lying under the cellular membrane, pass under
the ligament, and soon form a large net work of ves-
sels accompanying the iliac vessels; and here they
260 LONDON DISSECTOR, OR
are joined by the branches of lymphatics from the
superficial glands; sometimes the trunks, accompany-
ing the great vessels of the thigh, pass into a gland
immediately within the ligament; sometimes one or
two of them only enter into the glands high in the loins;
nay, sometimes a large vessel passes on directly to
the thoracic duct.
From six to eight or ten glands are seated in the
tract of the external iliac vessels, under the name. of
external iliac glands. And upon the inside of
the brim of the pelvis, and on the hypogastric vessels,
the glands are called the internal iliac glands.
On the psoas muscle, and on the loins, it is impossible
to trace the vessels as single trunks; we may observe
that one net-work of vessels ascends upon each psoas
muscle from the thigh; and it is there joined by the
lymphatics of the pelvis. These vessels are in a
manner united to those which cover the prominence
of the sacrum, and pass under the bifurcation of the
aorta. These two great lumbar plexuses of the
lymphatics continuing their ascent, many of the vessels
enter into the lumbar glands; and on the loins they are
joined by the absorbents of the testicle. By the union
of the lymphatics ascending from the right and left
side, with several large trunks of the lacteals from the
root of the mesentery, the thoracic duct is formed on
the third and fourth vertebrae of the loins.
OF THE LYMPHATICS OF THE ARM.
In the arm, as in the leg and thigh, there are two
sets of lymphatics: — the superficial and the deep-
seated. The first of these accompany the cutaneous
veins, the latter the deep arteries.
As in general there are too great veins on the fore-
arm, the basilic and cephalic veins; but particularly
as the veins which gather into the basilic trunk, on
the inner and lower edge of the fore-arm, are the
GUIDE TO ANATOMY. 261
larger and more numerous class; so it is found that
the course of the more numerous class of lymphatics
is on the lower and inner side of the fore-arm, and
that they accumulate about the basilic vein. These
are derived from the palm of the hand, and from the
ulnar edge of the hand. This set sometimes passes
into glands, seated on the brachial artery, near the
inner condyle of the humerus.
The absorbents which accompany the cephalic
vein arise from the side of the thumb and fore-
finger upon the back of the hand; they run on the
radial edge of the arm, with the veins which ascend
to form the cephalic vein. From the bend of the
arm, these vessels take a course on the outer edge of
the biceps, and then get between the inner edge of
the deltoid, and outer edge of the pectoral muscles;
they then pass under the clavicle, and descend into
the axillary glands. This set of absorbents receives
the branches from the outside of the arm in their
whole course.
There are absorbents arising from the back of the
hand, next the little finger, which, following some of
the branches of the basilic vein, (a larger branch of
which is called the ulnaris externa) turn round the
ulnar edge of the arm, are inserted into a gland, very
commonly found before and a little above the inner
condyle of the humerus. From this gland a large
lymphatic passes upwards, and attaching itself to the
brachial artery, splits and plays around it.
The deep-seated lymphatics of the arm accompany
the arteries in the same manner as the venae comites
do; in general, two with each artery. They all ter-
minate in the glands of the axilla, and can require no
particular description. The lymphatics, from the
muscles and integuments on the back of the shoulder,
also turn round and enter into the glands of the axilla.
The glands of the arm are small, and irregularly
262 LONDON DISSECTOR, OR
placed in the course of the humeral artery, from the
condyle to the axilla. They are from three to six
in number.
The glands of the axilla are large and nume-
rous; they receive the lymphatics from the arm, breast,
and shoulder; they lie in the deep cavity of the axilla,
formed by the tendons of the pectoralis major, and
latissimus dorsi muscles. They are embedded in a
loose cellular membrane, which, while it surrounds
and supports the vessels of the axilla in the motions
of the joint, gives them strength from its elasticity.
These glands do not all surround the axillary artery;
but a lower cluster is attached to the branches of the
subscapular artery, going forward on the side of the
chest, and to the thoracic arteries.
LYMPHATICS OF THE HEAD AND NECK.
Of the absorbents of the brain, little is known pre-
cisely; but none can deny the probability, that the
arteries, veins, and lymphatics bear the same relations
in the brain as in the other parts of the system. Lym-
phatic glands are observed in the course of the internal
jugular vein, and even in the foramen caroticum, which
are understood to belong to the lymphatics of the
brain. The lymphatics of the head are to be observed
in the course of the temporal and occipital arteries; the
latter class terminate in glands, seated behind the mas-
toid process of the temporal bone. The lymphatics of
the face have been observed to be very numerous, ac-
companying the facial and temporal arteries. But those
from the internal parts of the face and nose accompany
the internal maxillary artery, and fall into the glands
under the parotid, or in the course of that artery.
The lymphatics from the gums and jaws accompany
the internal maxillary artery, and emerge under the
angle of the jaw; and some of them joining the exter-
nal jugular vein, pass through glands near the top of
GUIDE TO ANATOMY. 263
the shoulder. The lymphatic vessels from the tongue
and parts about the os hyoides, take also the same
course.
There are in general several small lymphatic glands,
on the side of the face, on the buccinator muscle,
immersed in the surface of the parotid gland, and
under the zygomatic process. There are also glands
to be carefully noted, which lie under the tip of the
parotid gland, where it extends behind the angle of
the jaw, and also lying under the base of the jaw-bone,
close to the sub-maxillary gland, and on the course
of the facial artery.
The glands and absorbents of the neck are very
numerous, and the latter form an intricate and beauti-
ful plexus, several branches of which are to be ob-
served accompanying the external and internal jugular
veins. Some of the glands lie immediately under the
skin, and in the cellular membrane, on the outer edge
of the platisma myoides; many under that muscle,
and in the course of the external jugular vein. But
there are many seated deep, for the greater number
accompany the internal carotid artery, and internal
jugular vein, or their branches.
The lymphatics of the thyroid gland have been
raised by Mr. Cruickshanks, by plunging a lancet at
random into the substance of the gland, and blowing
into it, or throwing quicksilver into its cellular mem-
brane. The trunks of these lymphatics join the tho-
racic duct on the left side; and on the right side, they
unite with the right trunk of the absorbing system,
just as it is about to enter the jugular vein.
OF THE TRUNKS OF THE ABSORBENT SYSTEM.
The larger and proper trunk of the lymphatic sys-
tem is generally called the thoracic duct, because
it was first observed by Pecquet* to be a vessel which
* In the year 1651.
264 LONDON DISSECTOR, OR
conveyed the chyle through the diaphragm, and which
took its course through the whole length of the tho-
rax, to discharge its fluids into the veins near the
heart. The origin of this great trunk, called the
thoracic duct, is the union of the vessels which ascend
by the side of the common iliac arteries and veins,
and are derived from the pelvis and lower extremi-
ties. Upon the third and fourth lumbar vertebras,
and under the aorta, this trunk is frequently joined by
a large trunk of the lacteals, and then ascending, it
receives the greater number, or the larger trunks of
the lacteals. On the vertebras of the loins, the tho-
racic duct is by no means regular, either in its course,
or size, or shape; often it contracts, and again irregu-
larly dilates, as it seems to emerge from under the
aorta. On the uppermost vertebra of the loins, the
thoracic duct lies between the right crus of the dia-
phragm and the aorta. From this point it runs up on
the face of the dorsal vertebrae, and between the vena
azygos and the aorta. On the fourth dorsal vertebra
it passes under the aorta to gain the left side of it.
Here it is considerably enlarged, from the contracted
state which it assumes in the thorax. Sometimes it
splits, and again unites on the vertebras of the back.
Still ascending, it continues to incline to the left side,
and may be found by the side of the oesophagus.
The thoracic duct now emerges from the thorax,
and lies deep in the lower part of the neck, behind
the lower thyroid artery, and on the longus colli
muscle.
It rises above the level of the subclavian vein of
the left side, and here it receives the absorbents of
the head and neck, (of the left side,) and descends
again with a curve, and terminates in the angle formed
by the union of the subclavian vein and jugular vein
of the left side.
Sometimes there are two thoracic ducts; but this
GUIDE TO ANATOMY. 265
is very rare. Sometimes the duct splits near its ter-
mination, and the two branches enter the veins
separately; but, in general, when it splits in this man-
ner, it again unites before it terminates in the vein.
There is constantly a trunk in the anterior medias-
tinum under the sternum, almost as large as the tho-
racic duct itself, which is sometimes inserted into the
termination of the thoracic duct; sometimes into the
trunk of the absorbents of the right side, to be imme-
diately described.
THE TRUNK OF THE ABSORBENTS OF THE RIGHT
SIDE.
The absorbents, from the right side of the head
and neck, and from the right arm, do not run across
the neck, to unite with the great trunk of the system;
they have an opportunity of dropping their contents
into the angle between the right subclavian and the
right jugular vein. These vessels then uniting, form
a trunk which is little more than an inch, nay, some-
times not a quarter of an inch in length, but which
has nearly as great a diameter as the proper trunk of
the left side.
The trunk of the right side lies upon the subcla-
vian vein, and receives a very considerable number
of lymphatic vessels: not only does it receive the
lymphatics, from the right side of the head, thyroid
gland, neck, &c, and the lymphatics of the arm; but
it receives also those from the right side of the thorax
and diaphragm, from the lungs of this side, and from
the parts supplied by the mammary artery. Both in
this and in the great trunk there are many valves.
23
266 LONDON DISSECTOR, OR
OF THE LACTEALS AND LYMPHATICS OF THE
INTESTINAL CANAL.
The lymphatics situated on the alimentary canal
are named lacteals,* and both these and the other lym-
phatics are also termed absorbents.
The lacteals are those lymphatics or absorbents
situated on the intestinal canal, being named so from
the commencement of the duodenum to the termina-
tion of the rectum. But there are other absorbents
which carry the lymph from the tissue of the intestines,
and which are simply named lymphatics, although
they take the same course. They are subdivided
into lactea primi generis, and lactea secundi generis.
The lactea primi generis are those which extend
from the intestines to the lymphatic glands situated
in the folds of the mesentery; and the lactea secundi
generis are those which extend from the lymphatic
glands to the thoracic duct.
Mr. Cruickshanks has remarked a deep and a super-
ficial set of lacteals on the intestines; but for this
division there seems no necessity. Deep in the coats
the lacteals seem to accompany the blood vessels;
but when they get more superficial, they take a course
longitudinally on the canal, and after running a little
way, they take a sudden turn towards the mesentery.
As the greater frequency of the valvulae conniventes
in the jejunum, greatly increases the extent of the inner
surface of that gut, and consequently gives a greater
extent of origin to the lacteals; and, as here, the chyle
must be in the greater quantity, so the lacteals of
this portion of the gut, are larger and more nume-
rous than in any other part of the canal.
The lacteals do not attach themselves to the vessels
* Vasa chylifera.
GUIDE TO ANATOMY. 267
of the mesentery, but take a more superficial course.
Before they enter the mesenteric glands, they have
been called lacteals of the first order; when they
emerge from the first into the second glands, secondary
lacteals, or glands of the second order.
The absorbents of the stomach form three divisions:
one set accompanies the coronary artery and vein,
and enters the glands on the lesser curvature of the
stomach and the omentum minus. Those of the second
set accompany the left gastro-epiploic artery, and are
joined by the lymphatics of the omentum. The third
pass down upon the upper part of the duodenum, fol-
lowing the arteria gastro-epiploica dextra: these
descend to pass into the same class of glands, which
receive the lymphatics of the liver. The lymphatics
of the stomach are joined in their course by the lym-
phatics of the right side of the omentum.
The lacteals on the mesentery pass from one gland
to another, till they form one or two large trunks
only. These accompany the trunk of the superior
mesenteric artery, and run down on the right side of
the aorta, and join the thoracic duct. The absorb-
ents, from the rectum and colon of the left side, pass
into their proper glands, or sometimes into the lumbar
glands, and join the thoracic duct separately; those
from the right side of the colon join or mingle with
the lacteals in the root of the mesentery.
OF THE REMAINING ABSORBENTS OF THE SOLID
VISCERA.
Where the lymphatics of the lower extremity
descend over the brim of the pelvis, they are joined
by the absorbents of the bladder, vesiculae seminales,
and other parts in the pelvis: — small glands belonging
to this set, are attached to the internal iliac vessels.
In the female, the lower set of lymphatics, from the
268 LONDON DISSECTOR, OR
womb and vagina, also come by this route to join those
of the lower extremity, or run mingling with them.
Another set of lymphatics of the womb pass up with
the spermatic vessels.
The lymphatics of the testicle are very numerous.
They come in distinct sets from the body of the tes-
ticle, from the epidydimis, and from the tunica vagi-
nalis: then reaching the cord, from six or ten trunks,
and run up direct to the abdominal ring; passing the
ring, they turn outward, and then pass over the psoas
muscle and into the lumbar glands.
The lymphatics of the kidney are in two sets,
superficial and deep-seated; but the former are seldom
to be observed. Sometimes disease makes them
distinct. The internal lymphatics are demonstrated
by blowing into the veins, or tying a ligature and
kneading the substance of the kidney with the fingers;
when they rise, they are seen attached to the emul-
gent vessels, and go to join the lumbar glands, or ter-
minate in large lymphatics near the aorta.
It is needless to repeat that the absorbents of the
spleen are deep and superficial, — for this arrangement
is general in the solid viscera. Emerging from the
spleen, the lymphatics pass along the splenic vessels,
and enter into glands attached to the splenic artery
in its whole course. In this course they receive the
absorbents from the pancreas, and near the head of
the pancreas they are joined with those of the liver,
and with them enter into the thoracic duct.
The lymphatics of the liver are the most easily
detected, and they may be injected to greater minute-
ness, than any other lymphatics of the body. Although
they have many valves, yet they do not seem to close
the vessels entirely, nor interrupt the mercury from
passing from trunk to branch. The superficial lym-
phatics, which are so numerous that we may sometimes
see the mercury in them covering completely and ob-
GUIDE TO ANATOMY. 269
scuring a considerable part of the liver, have free
communication with the internal set of vessels, which
are also numerous and large. The principal route of
the lymphatics of the upper surface of the liver, is by
the broad ligament: these perforating the diaphragm,
j oin the trunk, which we have noticed under the sternum,
and in the anterior mediastinum. It would appear, how-
ever, that these lymphatics of the broad or suspensory
ligament, are by no means constant and uniform in their
course: for sometimes they run down towards the
lateral ligament, and perforate it there; sometimes
they pass down into the thoracic duct while still in
the belly. While other lymphatics of great size run
off from the convex surface of the liver upon the lat-
eral ligaments, and pierce the diaphragm there. The
lymphatics on the lower or concave surface of the
liver are more irregular than those of the convex
side. They unite with the deep lymphatics coming
out of the porta along with the vena portae, enter into
the glands, which are seated on the trunk of that
vessel, and join the thoracic duct near the root of the
superior mesenteric artery.
The lymphatics of the lungs are nearly as nume-
rous as those of the liver, but, indeed, it is more in
relation to the facility of injecting and demonstrating
the lymphatics, than to their comparative number,
that we speak of them in this manner. For example,
if the lymphatics of the other viscera could be injected
to as great minuteness as those of the liver, we should
cease to consider that viscus as more abundantly
supplied than other parts. The superficial lymphatics
of the lungs form areolae, and cover the surface almost
completely. They take a course to the root of the
lungs, where they are joined by the deep-seated ves-
sels, and together pass into the bronchial glands, and
here the lymphatics of both sides freely communicate.
The glands of the lungs are constantly found both
24*
270 LONDON DISSECTOR, OR
before and behind the bifurcation of the trachea;
often these glands are of a very dark color, nay, their
substance is often found resolved, as it were, into a
sac of ink-like fluid. Upon the arch of the aorta
and the root of the great branches are the cardiac
glands, which receive the lymphatics from the heart.
The absorbents from the heart are small, but very
numerous, and their larger branches attach themselves
to the coronary vessels; they then pass to the cardiac
glands and unite with the lymphatics which come
from the lungs, and so join the thoracic duct.
DIRECTIONS FOR MAKING LYM-
PHATIC PREPARATIONS.
GENERAL OBSERVATIONS.
1. The part should always be injected in a proper
tray, that the mercury with which the lymphatics are
to be filled, may be easily collected.
2. A lancet, with a curved needle ready threaded,
should be always at hand.
3. A bottle, whose neck is not so wide as to permit
the quicksilver tube going to the bottom, when placed
in it.
4. When injecting, if any circumstance renders it
necessary for the injector to put aside the tube with
the mercury, it should be placed in the bottle, the
mercury remaining in it, to be convenient, and to pre-
vent delay.
5. Injecting with mercury is always tedious, and
frequently unsuccessful. The parts exposed must be
kept moist, by sprinkling them with cold water.
GUIDE TO ANATOMY.
A SUPERIOR EXTREMITY.
271
To inject the lymphatics of an arm, choose orte from
a dropsical subject, without fat; make an incision into
the skin around the wrist, and seek diligently, with a
magnifying glass, for an absorbent, into which the pipe
is to be put, when the quicksilver will immediately run.
The shoulder should now be placed considerably lower
than the hand; and, when the mercury runs out at
the divided vessels in the axilla, tie them up, and also
the lymphatic, into which the pipe was introduced.
Then seek for another absorbent. When the mer-
cury ceases to run in a h mphatic, tie the vessel, and
seek for another.
Dissection. Begin at the lymphatics where the
mercury entered, and trace them; removing every
thing that obstructs their view, but preserve the glands.
AN INFERIOR EXTREMITY.
The limb for this purpose should also be taken
from a dropsical person, and the same method adopt-
ed as with the superior extremity, seeking as near to
the toes as possible for the lymphatics.
A PAROTID GLAND.
Cut down upon the masseter muscle, and seek for
the Stenonian duct, which is the excretory duct of
the parotid. Tie the quicksilver pipe in it, then fix
the tube, and pour into it the quicksilver; and, when
it ceases to run, remove the tube and pipe, and tie
the duct. Be particularly careful, in dissecting away
the gland, not to cut it.
Preservation. Dry it on a waxed board, and pre-
serve it on a blue paper and pasteboard, in spirit of
turpentine.
272 LONDON DISSECTOR, OR
LIVER.
The lymphatics running on the peritoneal coat of
the liver, and over the gall bladder, make a beautiful
preparation. The liver should be well soaked for
several days, and the pipe put into the lymphatics of
the suspensory and coronary ligaments, and the mer-
cury forced along them, breaking down the valves
with the nail, by pressing on the mercury. Secure
the vessels at the portae of the liver, when the mer-
cury gets there, and tie the lymphatics when filled.
Should the anatomist's attempt to force the quicksil-
ver beyond the valves be unsuccessful, he must fix
upon the most minute obvious branch, and let it run
its proper course.
Preservation. Throw some coarse injection into
the cavae hepaticae and vena portae, without heating
the liver thoroughly; inflate the gall bladder, and dry
the whole. Varnish it, and preserve it in the best
manner under a glass bell, or preserve the injected part
in proof spirit, without any wax injection.
LUNGS.
The superficial lymphatics of the lungs are to be
filled from the part most remote from the root of the
1 ungs.
Preservation. Cut away the part on which the
lymphatics are filled. Dry it on a waxed board, var-
nish it, and preserve it in a bottle, on a green or blue
piece of paper; or preserve it in proof spirit, without
drying it.
HAND.
Select the hand of an aged female (separated from
the arm by a transverse section, three inches above
the wrist,) that has died of a lingering disease. Soak
GUIDE TO ANATOMY. 273
out the blood in warm water, fix the pipe in the rad-
ial artery, then add the tube, and pour into it the
mercury. As the mercury appears in the other arte-
ries and veins, take them up and secure them with
ligatures. Should the mercury still escape from small
branches, put a cord round the arm, and with a piece
of wood tighten it, by twisting the cord, taking care
not to prevent the mercury passing into the hand.
Then suspend the hand in a glass filled with water,
and suspend also the tube and quicksilver, for a day
or two, that the mercury may get into the small ves-
sels. When injected, remove the pipe, and tie, by a
strong string, the fore-arm; put the hand into water,
until putrefaction separates the cuticle.
Preservation. Dry it carefully, and varnish it;
then fix the fore-arm in a pedestal of plaister of Paris,
and keep the preparation under a glass bell.
LACTEALS.
Remove the mesentery and intestines, if the former
be perfectly free from fat, and let them remain seve-
ral days in water, which should be frequently chang-
ed. Search for an absorbent, on the intestine, into
which introduce the quicksilver, which will run on
to the glands in the mesentery, where it will stop.
When the lacteals are filled, the preparation will be
improved by injecting the mesenteric arteries and
veins with red and yellow matter.
Preservation. Spread the mesentery on a waxed
board, inflate a portion of the intestine, remove all
that is useless; dry and varnish, and preserve it in a
glass frame.
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