DIAPHRAGM. - 
the front, and is marked by a phos notch pofteriorly. 
ence it has an n obfcur e refemblance to the leaf of trefoil, 
and confifts of two | nea portions, apna ale, a right an 
left; anda middle anterior part placed before and between 
this tendon is its 
broadet iad and is placed near to the bodies of the verte. 
bre: it becomes gradually narrower towards the front, and 
the obtufe oad of this part terminates at a fhort diflance be- 
hind the enfiform cartilage. It contilts of fibres purfuing 
very various directions, ‘and conneted into fafcienl, which 
ath other: 
e tothe centre. The rigut ala is generally 
From the whole ¢ circam derenice 
eee. e front 
abres oe died 
as ‘- en flora. cartilage. Th ney are often divide a into 
fe and Jeft pa:t, and at the nee) between thefe the cel- 
lular fubftance of the anterior medattinum communicates 
with that of the abdominal cavity. Sometimes this part is 
ing altogether, 
The lateral Gurnee the moft numerous ; they pr: 
es each fide of the tendon, diverge, and deferibe in es 
¢ femicircles with the convexity upwards. They ter- 
m: inate every par at the aways . the oe 2 oe 
and 
The pofterior ones and c 
aa the Be divifios, or crura af ie eee: thele 
are inferted i aponeurofis, extended from the end of the 
aft rib to the tran{verfe procefs of the firft lumbar vertebra, 
and fometimes called ligamentum arcuatum, alt h it 
us to be merely the upper edge of the aponeurolis of 
the tranfverfalis. The reft of the lateral fibres which in- 
creafe confiderably in length, are inferted by broad, diftin@, 
and flat, tendinous and flefhy portions on the inner furface 
of the cartilages of the fix laft ribs, and in fome inftances of 
the bone of the nbs. Thefe attachments meet with fimilar 
ones of the tranfverfalis, and a is fometimes a continue 
ity of fibre between the two 
The po en fibres Ai aapnaan: arifing from the 
ft itute a pretty large: 
of the vertebre ; an 
they feparate, and leave an oval opening, through which the 
ccfophagus and nerves of the eighth pair pafs from the cheft 
into the abdomen; this is the cardiac, celophageal, or fu- 
perior orifice of the diaphragm. ‘I'he two crura now d 
{cend nearly in a vertical dire@tion, and a. fafciculus of fibres 
is detached from each: thefe fafciculi crofs each other, and 
complete by their decuffation the lower part of the a 
phageal orifice, and then join the oppofite crura. Thea 
dcfcends from the le‘t crua to the right, is the 
The tw 
nm 
ned tendon, which is inferted in 
the front and fides of the bodies of the lumbar vertebre ; 
viz. into the two upper ones on the left, and three on the 
and fometimes mto the tranfverfe procefs of the 
The tendons of the two crura are united in the 
y an ‘aponeurotic arch, which forms the anterior 
ela . ie aortic orifice, and which ees immediately 
OL 
the greater part p- dears goes from 
“however, only by cellular texture, in fome fitua 
over that veffel: they are a'fo confufed with the longitudi- 
nal ligament that extends along as bodies of the vertebra, 
o that their extent cannot always be very eafily defined. 
‘They are more manifelt on the made than on the anterior 
furface of the crura 
Parts, which pafs through the Diaphragm. 
Thea aorta, thoracic dud, 
eighth pair come through the 
in the crura of the di See m. 
tranfon't t the efe parts, are rat as 
cefophagus, and nerves of the 
openings already mentioned 
€ two ie da alan s which 
owarcs the left fide 
meepar ie faiciculi of and couse the acrta 
and ce fophag agus are feparated from each otber afe fai- 
cicull. celophag geal cpening is compofed entirely of 
mufcular abres, and bncreior liable to change in its ee 
fions: the aortic or-fice, on the contrary, is never affcétec, 
its diameter: the lower part being formed by the aes 
of the vertebre ; the fides by the tendons of the crura 
line. 
fplanchnic nerves, and the trunks of the great fympathetics, 
go through the cruraof the diaphragm feparately on eac 
fide; a are generally accompanied by the origin of the vena: 
azyec 
The ‘inferior or abdominal furface of this mufcle forms’ a 
nd fpleen ; and at 
nal. ect and kidnies 
Its fuperior tho= 
a 
the oo. crura. The dextro-finiftral diameter is great- 
er than any antero-pofterior meafurement. e angle 
whieh its furface a = the fpine, is much more acuce 
than that with the tler 
The pleura and seine nearly touch, or are feparated 
tions of the 
aphragm; as at the paflage of the vena Cava, and at the 
satel of the anterior fibres. 
"Adlon 
