into two nearly equal portions, the left portion, however, being somewhat 

 the larger of the two. The cephalic surface is in contact, to the left, with 

 the diaphragm and, to the right, with the visceral surface of the ventral por- 

 tion of the liver, Pis. VII and III. The reticulum is separated from the 

 pericardium of the heart by an interval of only two to four centimeters, 

 Figs. 4 and 7. The left surface of the reticulum is related to the diaphragm 

 and the ventral extremity of the spleen. The caudal surface is in contact 

 with the rumen, omasum and abomasum. Pis. IV, VIII. The close prox- 

 imity of the reticulum to the heart and its relation to the fifth and sixth 

 intercostal spaces deserve particular attention for the reason that sensitive- 

 ness here points to the possibility of an injury to the reticulum and the 

 diaphragm from some sharp-pointed foreign body that has become lodged 

 in the reticulum and has penetrated these structures. 



The oesophageal groove begins at the cardiac or gastric end of the oesophagus, 

 extends ventrally on the medial wall of the reticulum and ends at the reticulo- 

 omasal orifice. Its average length is from 15 to 20 cm. Its direction is 

 nearly dorso-ventral but inclines slightly cephalad (sometimes caudad) and 

 somewhat medially in its ventral part. In this specimen the ventral or 

 omasal end of the groove was a little caudal to the vertical plane of the 

 dorsal or oesophageal end. More commonly, however, just the reverse of 

 this obtains, i.e. the ventral or omasal end lies a little cephalad of the vertical 

 plane of the dorsal or oesophageal end of the groove. 



The nxmino-reticular orifice (ostium rumino-reticulare). The reticulum 

 is partially separated from the cephalic end of the dorsal sac of the rumen 

 by a nearly vertical fold formed by the apposition of the walls of the two 

 compartments. This rumino-reticular fold is opposite the space between 

 the seventh and eighth ribs. The free edge of the fold forms the ventral 

 and lateral boundaries of the large oval rumino-reticular orifice, PI. VIII. 

 The relation of this orifice to the oesophagus is such that it is clearly ap- 

 parent that food or water may readily pass from the oesophagus directly 

 into the rumen. 



The omasum is very clearly defined from the other compartments. The 

 greater portion of it is situated to the right of the median plane. It extends 

 from opposite the cephalic edge of the seventh rib, near the middle of the 

 rib, to opposite the caudal edge of the eleventh rib at its costo-chondral 

 junction, PI. IV. The parietal, or right, surface is in contact with the 

 diaphragm, liver, gall-bladder, abomasum and the beginning of the duo- 

 dentrni. Opposite the eighth and ninth intercostal spaces, for a distance of 



