33 



wider. The inner membrane is produced into a few irregular folds, 

 and for half an inch within the anus is of dark leaden colour, the 

 pigmentum being apparently continued inwards for that extent. 



" From the complexity of the stomach, the great extent of the 

 alimentary canal, its vast muscular power, and glandular appendages, 

 the digestive functions must be extremely vigorous in this animal. The 

 vigour of the digestive functions obviously relates, in the herbivorous 

 section of Cetacea, to the low organized indigestible character of their 

 nutriment ; but the complicated stomach and long intestinal canal of 

 the carnivorous Cetacea must have other relations than to the kind 

 of food. These modifications of the digestive system, for example, 

 cannot be so explained in the Grampus, which preys on the highly 

 organized mammalia of its own class. It is not to the nature of 

 the food, but to the quantity of nutriment that is required to be 

 obtained from it, that I conceive the peculiarities of the digestive 

 system in the carnivorous Cetacea to relate. In no other Carnivora 

 is the same quantity of blood, the same mass of fat to be eliminated 

 from the raw material of the food : the digestive system is, there- 

 fore, perfected in these warm-blooded carnivorous Mammalia to 

 meet the contingencies of their aquatic life. 



" The omentum is continued from the great curvature both of the 

 cardiac and pyloric divisions of the stomach ; though short, it is 

 much more distinctly developed than in the carnivorous Cetacea ; it 

 contains no adipose matter. 



" The mesentery like the omentum was thin, with little fat, and a 

 few absorbent glands of the size of French beans were scattered in it. 

 The absorbents going to these glands were very small." 



Having described various other particulars connected with the chy- 

 lopoietic viscera, and the individual dilFerences which they presented 

 in the three specimens dissected, Mr. Owen proceeded to observe as 

 follows : — 



" The views taken by Cuvier of the natural affinities of the Du- 

 gong and other herbivorous Cetacea, as expressed in his latest clas- 

 sification, in which they form part of the same order as the carnivo- 

 rous Cetacea, axe undoubtedly questionable, and have been dissented 

 from by De Blainville and other eminent authorities in zoology. If, 

 indeed, the object of every good classification be, what Cuvier states 

 it to be, to ejiable the naturalist to express in general propositions 

 structures and attributes common to each given group, the conjunc- 

 tion of the Dugong with the Dolphin fails in this respect in regard 

 to almost all the important points of internal organization. 



" It is this question which may give interest to the pi-esent ana- 

 tomical details, some of which are not new, and which I should not 

 have intruded upon the notice of the Society had they previously been 

 considered with reference to the important zoological question still 

 at issue. 



" In proceeding with our investigation of the abdominal viscera, 

 we find, with respect to the biliary organs, that the Dugong deviates 

 in a marked degree from the ordinary Cetacea in the presence of a 



