228 RODENTIA. 



The other bags, viz. those belonging to the anns, are a pair on each 

 side ; are more of a pyramidal figure, being thicker at the fundus, and 

 becoming small towards the anus : they open on each side in the sulcus, 

 between the anus and prepuce, by very small openings. They contain 

 a thick oil of a light brown colour, about the consistence of common 

 butter, but rather more tenacious. This has something of the castor 

 smell;, but not so much as the other 1 . 



The Water-rat [or Water Vole 2 [Arvicola amphibia), Lacep.]. 



The specimen about to be described measured seven inches from the 

 tip of the snout to the anus, and weighed six ounces and seven drachms. 



On opening the abdomen no epiploon was visible, because it was very 

 short and hidden by the stomach, which extended as far as the umbilical 

 region ; the duodenum was seen on the side of the stomach, and nothing 

 else, with the exception of the caecum, was discernible between the 

 stomach and the bladder. The liver was situated more towards the 

 right side than the left, and the stomach a little more to the left than 

 towards the right. 



The duodenum was placed on the right side, where it made some 

 windings ; it turned upon itself in the right flank, and was prolonged 

 forwards to join the jejunum, the convolutions of which were above the 

 caecum in the anterior part of the umbilical region, and on the right 

 side. The convolutions of the ileum were likewise above the caecum in 

 the right flank, and in the umbilical region. The caecum extended from 

 left to right in the flanks and hypogastrium : in other subjects I have 

 seen it in the umbilical region, where it formed some sinuosities. The 

 colon had many nearly spiral convolutions in the posterior part of the 

 abdomen; it then passed from left to right in the umbilical region 

 above the small intestines ; it afterwards curved forward in the right 

 side, and turning inwards above the stomach, ran backwards in the 

 middle of the abdomen to the rectum. 



The membranes of the stomach and intestines were all so thin, that 

 their contents shining through them gave them a greyish colour. The 

 figure of the stomach was very irregular, the great cul-de-sac being 

 deep, and the right portion of the viscus separated from the left by a 

 constriction, which reduced its circumference to an inch and a half at 

 the point of junction : between this constriction and the pylorus, the 

 anterior surface of the pylorus presented a large convexity, which ap- 

 peared to be a third stomach ; but, on opening the organ, I found that 



1 [Hunt. Preps. Nos. 2118—2122.] 



2 [It is more nearly allied to the beaver than to the rat.] 



