322 STRUCTURE OF THE SHEEP. 



tend the stomachs, the situation of the reticuhim will become 

 reversed, rising up towards the oesophagus ; and thus if this 

 viscus is disteiided in hoove, as from its free communication 

 with the rumen it probably is, it must press upon the dia- 

 phragm with very considerable force, greater in proportion 

 even that the rumen itself The contents of this stomach 

 are more liquid than those of the others. 



Somewhat before the end of the entrance of the second, 

 the canal terminates, as it were, in the third stomach, the 

 maniplus or manifolds, so called from its curious internal 

 structure, which is formed by a great number of plaits or 

 folds arranged longitudinally in a direction from the entrance 

 of the stomach ; so that although it is not large, externally 

 not exceeding the reticulum, its internal surface is increased 

 in more than a tenfold degree. These plaits are very cu- 

 riously arranged, being in the form of seven or eight groups 

 of six leaves, each leaf dissimilar in length, the longest ex- 

 tending almost from the upper to the lower part of the stom- 

 ach. These leaves are studded with numerous small papillae, 

 much harder than those of the reticulum, and some on the 



edges of the plaits of the shape of a bent cone, thus /Y , 



the point directed towards the entrance. It has been found 

 in certain cows that would never retain their food, but were 

 continually scouring, that these plaits were unusually short. 



The maniplus has but one opening, but this opening is in 

 direct communication with both the canal and the fourth 

 stomach, as may be seen in the sketch, page 320. The 

 plaits are studded with numerous minute papillae, somewhat 

 similar to those found in the reticulum. The maniplus pos- 

 sesses four coats like the others, and its external appearance 

 is globular. Its contents are generally found of a much 

 harder consistence than those of the other stomachs. 



This stomach, when full, is found above the oesophageal! 

 canal, forming, indeed, a portion of its roof, and its longest 

 leaves fall down, as it were, almost into that canal. 



The ahomasum, as the fourth stomach is called, is, in fact, 

 the true stomach, being that which secretes the gastric juice 

 by which the food is converted into chyme. It is this pe- 

 culiar acid which gives it the power of coagulating milk, and 

 in calves it is particularly employed for this purpose in the 

 manufacture of cheese, under the term rennet. 



