Material for the Study of Ruminants. 



5 



The abomasus measures along the middle of the curvature about 

 23 cm. its greatest transversal diameter is about 7 cm. 



With regard to the general shape the stomach of the Black- 

 buck seems to differ from must ruminants of which this organ is known 

 to me. Both sacks of the paunch are almost equal in size as in the 

 common sheep, but their terminal blind sacks are more separated from 

 each other and more equally rounded than in the latter. The rounded 

 shape is also different from that of the Cervicornia as well. The 

 paunch of the Saiga is termed »bifid» by Murie (1. c), but he does 

 not give any detailed description. As in the Gnu sulcus longitudinalis 

 dexter accessorius is better developed in the Black-buck than sulcus 

 longitudinalis itself. On the dorsal division of the paunch there is no 

 sulcus coronarius visible. This depends upon the fact that the entire 

 portion of this division which forms the rounded posterior blind end,, 

 as described above, is not homologous with the saccus cœcus dorsalis 

 of the sheep. But if the ventricle of the Black-buck is seen from the 

 left side there may be detected in the fissure beetween both sacks 

 a small, somewhat pointed, pocket from the dorsal division which cur- 

 ves ventrally so that it lies close to the ventral saccus cœcus. This is 

 the homologen to the saccus cœcus dorsalis of the sheep and other ru- 

 minants. From this can be concluded that the dorsal division of the 

 paunch of the Black-buck has been subjected to a reduction when 

 compared with other forms. 



The shape of the reticulum as described above seems also to 

 be characteristic of the Black-buck. The cells of this division are as 

 in the Saiga, divided by secondary stellate septa. 



In the Saiga Murie states that the psalterium is » comparatively 

 small». In this animal as can be seen from the measurements re- 

 corded above it is very small and might nearly be termed rudimentary 

 when its size is compared with that of the other divisions of the sto- 

 mach. In this respect therefore, the Black-buck differs in a consider- 

 able degree from Ovis and C«pra v ). 



The abomasus of the Black-buck is provided with about 19 

 longitudinal folds. These are best developed on both sides of the lesser 

 curvature, but short and situated at a greater distance from each 

 other at the greater curvature. They are, as it seems, a little more 



1 ) 1 take this opportunity to state that the psalterium of Connochcetes gnu is quadri- 

 plicate which for certain reasons could not be ascertained when I wrote my paper on the soft 

 anatomy of this animal. K. Sv. Vet. Akad Handl. Bd. 35. 



