NATURAL SCIENCES OP PHILADELPHIA. 457 



but little from that of the Dugong as described by Prof. Owen. 

 The gland in situ extended completely across the abdominal 

 cavity, and measured in the smallest specimen from edge of right 

 lobe to that of left 14 inches; the breadth of the right and left 

 lobes was respectively 7-| and 6^ inches, their depth fore and aft 

 8 inches and 7 inches. The liver in the smallest specimen weighed 

 2 pounds 14^ ounces av. I have nothing to add about the gall- 

 bladder save to notice its presence. The pancreas, 6^ inches long, 

 was much lobulated, and, as Dr. Murie states, pale but firm in con- 

 sistence. Ductus communis choledochus in both my specimens 

 opened into intestine close to the pylorus, while the pancreatic 

 duct opened 1^ inches from the ductus communis. This disposi- 

 tion is different from that noticed b} T Dr. Murie, he stating at 

 page 173, in speaking of the pancreas, " its duct opens into the in- 

 testine close to the pylorus," while at page 174 he says "the ductus 

 communis choledochus penetrates the intestine about 3 inches 

 from the pylorus." 



Dr. Murie does not refer to the spleen. I found it in its usual 

 position, but was struck with its very small size, it measuring in 

 the smallest animal only 2^ inches long and 1 inch wide. In form 

 it was oval and of the usual color. Unfortunately the spleen of 

 the Sirenia sheds no light which will help to clear up the difficul- 

 ties which envelop any explanation of the general physiology of 

 this organ. Its small size, as in the Cetacea, is not in harmony 

 with the idea of its being either the birthplace or the grave of the 

 red corpuscles (which in the Manatee I noticed were very numer- 

 ous, though in other respects they presented nothing peculiar), 

 while it is in direct contradiction with the theory held by some 

 physiologists of the organ holding blood as a sponge to be pressed 

 out by the distended stomach when needed in digestion. 



Eespiratory Apparatus. As the peculiar disposition of the 

 diaphragm and the characters of the respiratory organs generally 

 have often been described, I will limit myself here to simply giving 

 measurements. The trachea of the smallest specimen was 4 inches 

 long from the larynx to where it bifurcates. The right bronchus 

 measured 6 inches in length, the right lung 25 inches, the left 

 bronchus 5 inches, the left lung 27 inches. The bronchi in my 

 specimen are more oblique than as represented by Dr. Murie. I 

 have nothing new to offer in reference to the larynx. I noticed 

 the usual muscles were well developed. 

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