OKGANS OF DIGESTION. 321 



DESCRIPTION OF THE CUT. 



A< 'Hie lower part of the asophaffus, showing ite external coat. 



B. Its internal coat at its termination. 



C. The upper compartment of the rumen, or first stomach, showing its internal coat 

 . D. The strong muscular band which divides the lower from the upper compartment 



£. The lower compartment of the rumen. 



F. Another muscular band. 



G G. The external coat of the rumen. 



H. The entrance to the rumen cut open, and its opposite part reflected back, so aa 



to exhibit an internal view of the second stomach. 

 I. The external coat of the reticulum, or second stomacjd. 

 J J J J. Thfr muscular pillars forming the floor of the msophagean canal when 



close, but now spread open to show the second stomach. 

 K K. An intt^rnal view of the reticulum, or second stomach, showing Its peculiar 



honeycomb structure. 

 L Ii. The continuation of the OBsophagean canal at the entrance to the third 



stomach. ■> 



M M. An internal view of the maniplus, or third stomach, showing its peculiar 



iblds or plaits. 

 N N. Tbe fleshy lip^, which act as valves to guard the entrance between them to 



the fourth stomach. ^ 



O. The termination of the cesophagean canal. 

 P P. The external coat of the ahomaswm, or fourth stomach. 

 Q. Q,. The internal coat of the abomasum, or fourth stomach, showing its folds. 



Both' these coats are displayed by slitting open the stomach and then pinning 

 the duplications together, at its upper part. 

 R R. The valve formed by puckerings of the internal coat, and guarding the en- 

 trance into the small intestines. 

 S. The internal coat of the small intestines. 



oped. It is globular in shape and somewhat larger than the 

 maniplus, and is familiar to us in tripe, not only from its cel- 

 lular structure, but from its being thicker than the others. 

 Its internal aspect is very singular, having a vast number, 

 indeed several hundred," of shallow cells somewhat like a 

 honeycomb. These cells are much smaller at the part of 

 the viscus nearest the entrance, and gradually increase in size 

 from this point. The sides of these cells consist of ridges 

 formed by the mucous and cuticular coats, and smaller ridges 

 are also observed running ucross within the cells. Most of 

 them are pentagonal, but-many have six sides, and on their 

 surface we observe an immense number of sharp-pointed 

 papillae much smaller in size though sharper than those of 

 the rumen, and which secrete a mucous fluid. This viscus 

 has the same coats as the rumen, but the muscular coat has 

 two layers of strong fibres arranged both transversely and 

 longitudinally. The opening into this stomach is of some 

 extent compared to its size ; the duplications or lips which 

 form it are indeed .the floor of the greater portion of the ceso- 

 phagean canal. Though in the ordinary state the roof or 

 upper part of the reticulum is the floor of the ©sophagean 

 canal, yet if air is pumped iiito the oesophagus so as to dis-* 



