398 THE MUSCULAR SYSTEM. \ 
FASCIA. 
The fascize of the abdominal wall are—ewxternally, the superficial and deep fascize ; 
internally, the fascia transversalis, continuous with the diaphragmatic, lumbar, 
psoas, iliac, and pelvic fascive, and lined within by the extra-peritoneal tissue. 
The superficial fascia of the abdomen is lable to contain a large quantity 
of fat. It is separated in the groin into ¢wo layers: a superficial fatty layer 
continuous over Poupart’s ligament with the fascia of the front of the thigh, 
and a deeper membranous layer attached to the inner half of Poupart’s ligament, 
and more externally to the fascia lata of the thigh below Poupart’s ligament. The 
two layers are separated by the lymphatic glands and the superficial vessels of the 
groin. Higher up in the abdominal wall the two layers blend together, and traced 
downwards over the spermatic cord, they unite to form the fascia and dartos 
muscle of the scrotum. The attachment of the fascia to the groin prevents the 
passage into the thigh of extravasated fluid in the abdominal wall. 
The deep fascia of the abdominal wall resembles similar fascize in other situa- 
tions. It forms an investment for the obliquus externus muscle, and becomes thin 
and almost imper- 
ceptiblein relation 
to the aponeurosis 
> of that muscle. 
The fascial lin- 
ing of the ab- 
dominal cavity 
esa th peel aca (fascia transver- 
__Superficial = gals) consists of a 
<== epigastric vessels : 
]__ Superficial layer of continuous layer . 
superficial fascia of membrane 
Superior external : : 
pudic vessels which receives 
Tlio-inguinal nerve different names 
Spermatie cord in different parts 
of its extent. It 
covers the deep 
surface of the 
transversalis mus- 
cle, and is con- 
tinuous internally 
(through the 
lumbar fascia) 
pal p05 Tae a : with the fasciee of 
Fic, 292.—THE GROIN. STRUCTURES BETWEEN THE LAYERS OF THE 
SUPERFICIAL FAscra. the quadratus 
lumborum and the 
psoas. It is continuous above with the diaphragmatic fascia, and below (the iliac 
crest and Poupart’s ligament intervening) with the fascia iliaca. Along with the 
last-named fascia it forms the femoral sheath. It is pierced by the spermatic cord 
or round ligament at the internal abdominal ring, and forms the infundibuliform 
fascia. It is lined internally by the peritoneum, from which it is separated by a 
thick layer of extra-peritoneal tissue. 
The extra-peritoneal layer of tissue is usually loaded with fat; it envelops the 
kidneys, ureters, supra-renal capsules, abdominal aorta and inferior vena cava and 
their branches, and forms sheaths for the vessels and ducts (ureter, vas deferens, 
ete.). It is continuous upwards into the thorax through the aortic opening in the 
diaphragm, and below is in continuity with a similar tissue in the pelvis. It not 
only completely invests the kidneys and suprarenal capsules, but it also becomes 
interpolated between the layers of peritoneum upholding and enveloping the 
intestines. This tissue is absent in relation to the diaphragm. 
Superficial layer of 
superficial fascia I 
Superficial circumflex iliae vessels 
Inguinal lymphatic elands—ilt 
\\} 
Deep layer of superficial fascia 
Femoral lymphatie glands 
Crural branch of \ 
genito-crural nerve [N 
Superficial layer of. 
superticial fascia 
Internal saphenous vein 
THE MUSCLES OF THE ABDOMINAL WALL. 
The lateral muscles comprise the obliquus externus, obliquus internus, and 
transversalis abdominis, 
