136 THE VISCERAL ANATOMY 
and its position can be best understood from the accompanying draw- 
ing, in which it is seen that the corrugated white opaque epithelium 
only covers about one-fourth of the whole cavity—namely, the margins 
of the cesophagus for about an inch, and the diverticulum, from which 
it extends to the right, and backwards for a short distance. The walls 
of the stomach are nearly uniform in thickness, being a little more 
muscular at the cardiac extremity and along the lesser curvature than 
elsewhere. When the organ is fully distended the diverticulum be- 
comes less conspicuous, the direction of its superficial fibres being 
from its base to its apex. The pyloric muscular ring is strong and 
nearly an inch thick, projecting into the tube. 
The small intestine is 36 ft. long, and of a nearly uniform circum- 
ference of 6 inches, reaching 7 inches in the duodenum. For the first 
six inches after the pylorus the mucous membrane is smooth and simple, 
much like that in the pyloric portion of the stomach. The seventh and 
eighth inches present irregular folds, which immediately give place to 
a perfectly uniform series of thin, continuous (or nearly continuous), 
transverse foldings, just like the valvule conniventes of the human 
Fig. 4. 
Mucous membrane of the small intestine, natural size, showing the valvule 
conniyentes. 
