COMPARATIVE ANATOMY OP PANCREAS. 



101 



The pancreas of the Doubtful Reptiles assumes the appearance presented by that 

 of the Stingray, Shark, and warm-blooded animals. 



In the Menobranchus maculatus, it is an irregularly-shaped gland, having four 

 principal lobes diverging from each other at right angles, thus presenting a stellate 



arrangement. 



Fig. 14. 



Stomach, spleen, and pancreas of the Menobranchus maculatus. Reduced one-half diameter. — A. Stomach. S. Spleen. 



P. Pancreas. D. Small intestine. 



The pancreas of the Hellbender [Menopoma alleghanensis) is a long, delicate, light 

 yellow gland, which commences near the pyloric extremity of the stomach, and 

 extends down along the duodenum and small intestine for about three inches. 

 Its inferior portion is more expanded than the superior. (See Fig. 24.) The 

 pancreas of the Congo Snake [Ampliiuma means) is similar in structure and appear- 

 ance to that of the Menopoma alleghanensis, with the exception that it is broader and 

 thicker. (See Fig. 23.) 



In the Batrachia, the pancreas presents a developed appearance, and generally 

 commences by a small slender lobe at the pyloric extremity of the stomach, and, 

 passing downwards and forwards, expands into a broad lobulated mass. As in 

 many other cold-blooded animals, it is not in contact with the spleen. 



I have examined many American Ophidians, 1 and in each the pancreas is a 

 compact, ovoid gland, often kidney-shaped, situated in contact superiorly with the 



1 For example, Banded Rattlesnake (Crotcdus ditrissirs), the Water Rattlesnake (Crotcdus adaman- 

 teus), Ground Rattlesnake (Cratalophorus miliarius), Water Mokeson (Trigortoceplmlus piscivorus), 

 Copperhead (Trigonocepludiis contortrix), Hog-nose Viper (Heierodon plalyrhinos), Black Viper 

 (Heterodon niger), Grass Snake (Tropidonotus ordinatus), Water Snake (Tropidonotus fasciatus). Green 

 Snake (Leptophis cestivm), Coaehwhip Snake (Psaminophis fta gel/if ormis), Indigo Snake (Coluber 

 couperi), Chicken Snake (Coluber quadrivittatus), Corn Snake (Coluber guttatus), Black Snake (Coluber 

 constrictor). 



