ANATOMY OF THE BEAVER. 73' 



The length and size of the intestines in animals are 

 proportionate to the nature and nutritious qualities of 

 their food. In the carnivora, the intestinal canal is 

 shorter and less complicated than in the herbivora. 

 In the beaver, the length of the small intestines 

 averages 25 feet. They are destitute of valvulse 

 conniventes, which are confined to man/ but the vil- 

 lous coat is well developed. Sixteen patches of 

 Peyer's glands were counted in one subject. The 

 pancreas is long and delicate. Its duct enters the in- 

 testine 25" from the pyloric orifice, while that of the 

 gall-bladder enters but 4" from the pylorus. 



The extremity of the small intestine projects a 

 little into the colon, and the orifice is circular. 



Between the colon and caecum is a circular band of 

 muscular fibres acting both as a constrictor and a 

 valve. The caecum is larger than the stomach. 

 Its capacity when filled with water is 5 pints and 

 3 gills, and that of the stomach is 3 pints and 1 

 gill. The caecum is on a line with the colon for 7" or 

 8", it then forms an angle, and gradually diminishes 

 in size to its extremity. In shape it resembles a 



^ "It is remarkable that these folds (valvulse conniventes) are 

 peculiar to the human subject. No other animal, so far as we know, 

 exhibits any arrangement of transverse folds of the intestinal mu- 

 cous membrane resembling them." — "The Physiological Anatomy 

 and Physiology of Man. By Todd and Bowman." Phila. ed., 

 p. 5T4. 



Note. — In the stomach of the beaver I have found a very fine 

 filamentous worm, 40'" in length, species unknown. Large num- 

 bers of a long, slender white worm, B" to 5" in length, were 

 found ia the peritoneal cavity (Filaria, species not known), also in 

 the colon, and especially in the caecum, sclerostema, male and 

 female, species not known, and the amphistoma subtriquetrum. 



