ABDOMINAL VISCERA OF THE HORSE. 6/5 
sponding surface of the viscus, and, firstly, more especially on to 
the lesser curvature, where it is loosely connected with the other 
coats, and, the middle portion being more adherent, gives 
rise to two folds laterally, which seem to stretch from the car- 
diac to the pyloric orifices, to bind the two together, necessarily 
leaving a pit or cul-de-sac between them. At the pyloric end 
the peritoneum comes off from the concave surface of the liver 
on to the stomach, constituting the gastro-hepatic or lesser omen- 
tum, the anterior layer of which comes from the anterior part 
of the concave surface of the liver, whilst the posterior layer 
comes from the posterior part of the same, so that the two en- 
close the vessels going to and from the porta. 
Having formed a covering to the corresponding surface of the 
stomach, the layers of peritoneum meet at the greater curva- 
ture. In following them from this point the description will be 
facilitated by alluding to the two separately, as they meet to form 
the gastro-splenic and gastro-colic omenta, as well as the 
omental sac. In forming the latter, they so blend as merely to 
constitute a fine reticulated vascular layer, inseparable into two, 
except near the margins of the viscera. Distinguishing the 
anterior or external layer as A, and the posterior or internal one 
as B, their arrangement admits of exposition in the following 
terms : — 
A passes from the anterior surface of the stomach, forms the 
loose omentum, and gets on to the transverse colon and spleen. 
Reaching the latter, it is reflected over its superior surface at 
the posterior margin of the hilus, so as to contribute to the form- 
ation of the gastro-splenic omentum, and extends round the 
free posterior margin of the viscus on to the inferior surface, 
passing to the right on to the left kidney, and, anteriorly reach- 
ing the supero-anterior part of the spleen, is reflected from it so 
as to continue as the outer layer of the loose omentum. Further 
to the right, A is traceable on to the inferior surface of the 
transverse colon, and, extending round the posterior part of the 
latter, is found to ascend up to the spine, and then turn back- 
wards and downwards to form the mesentery. 
B, or the internal layer of peritoneum, passes from the pos- 
terior surface of the stomach till it reaches the infero-anterior 
border of the transverse colon, as well as the hilus of the spleen. 
After covering the anterior surface of the colon, it ascends up 
to the pillars of the diaphragm clothing the anterior part of the 
pancreas, which is thus held between A and B, or layers of 
the transverse meso-colon. A little to the left of this, B passes 
on to the anterior margin of the hilus of the spleen, forming the 
inner or posterior layer of the gastro-splenic omentum. 
From this arrangement it results that the peritoneum, inform- 
