PLATE VIII. 



Fro. 27. — Dorsal view of the digestive organs. Natural size. 



Ao, dorsal aorta, dividing into innominate and buccal arteries. 



B, buccal mass. 



C, C, posterior columellar arteries. 

 Goe, coecum. 



GL, gastric ligament. 



H, hepatic artery. 



P, first loop of the intestine around the coecum. 



I-. posteriorly directed portion of the second loop of the intestine. 



P, anteriorly directed portion of the second loop of the intestine. 



IA, intestinal artery. 



IL, intestinal ligament. 



L, L, left lobes of the liver. 



I/, I/, right lobes of the liver. 



Oe, oesophagus (proventriculus). 



PA, anterior proventricular artery. 



PX, PX, pallio-nuchal arteries. 



PP, posterior proventricular artery. 



St, stomach. 

 Fig. 28. — Dorsal view of the buccal mass, the buccal membrane and enveloping muscular membrane being cut in the 

 median dorsal line and opened. X 2. 



Ao, aorta, dividing into innominate and buccal arteries. 



BM, buccal membrane. 



CG, cerebral ganglion, giving off nerves to the buccal mass. 



DLR, dorso-lateral buccal retractor muscles. 



DR, dorsal buccal retractor muscle. 



L.T, tip of lower jaw. 



LJ', posterior portion of the outer flange of the lower jaw. 



LM, levator muscle of the buccal mass. 



M, mandibular muscle. 



MM, enveloping muscular membrane. 



N, nerves to the buccal membrane. 



Oe, oesophagus. 



U.J, upper jaw. 



X, buccal membrane, passing onto the base of the superior labial lobe. 

 Fig. 29. — The buccal mass turned upward and backward so as to show its ventral surface and the dorsal surface of 



Van der Hoeven's organ. Natural size. 

 Fig. 30. — Side view of the upper jaw. X 2. 



Fig. 31. — View of the inner surface <>1 half of the lower jaw, cut in order to show the small inner tlauge. X 2. 

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