CASTOROLOGIA. 185 



In the " Memoires de 1' Academic Imperiale des Sciences de Saint- 

 Petersbourg,i855," Dr. J. F. Brandt gave an account of his researches 

 among the beavers of Russia, which is reprinted and discussed ad 

 item by Dr. W. W. Ely, in the appendix to I,ewis Morgan's "The 

 American Beaver." Dr. Brandt's conclusions may be summed up 

 in the following words : ' ' "With respect to the nasal bones, there re- 

 mains only their more considerable length in comparison with the 

 skull, as a mark of the European beaver." Dr. Ely's investigations 

 and comparisons have resulted in an intermediate position, which is 

 thus stated : ' ' The extremes of difference, in their aggregate, on 

 the one side and the other, are sufficiently striking to justify us in 

 regarding them as varieties of one and the same species ; while the 

 want of constancy in these peculiarities suggests the inference, that 

 these variations are due to long separation of the races, and to ac- 

 cidental causes, rather than to original diversity of the stock." 



The skull of the beaver is stronger and more solid than that of 

 any other rodent. Many rough prominences mark the strong muscle 

 attachments. The lower jaw is very massive and also shows clearly 

 the powerful muscular processes. The skeleton has several minor 

 generic characteristics, but none are really remarkable if we except, 

 perhaps, the vertebrse, which are divided into seven cervical or neck ; 

 fourteen dorsal, or back ; five lumbar, or loins ; four sacral (conflu- 

 ent) forming the pelvis or haunch ; and twenty-five caudal, or tail ; 

 representing in all fifty- five vertebrae. In the tail, the bones gradu- 

 ally diminish in size and lose the vertebral character, ' ' in the eighth 

 or ninth the spinous processes disappear ; in the tenth the spinal 

 canal becomes a mere groove ; and toward the end of the tail the 

 transverse processes lengthen and broaden becoming bifid or double. ' ' 



The preservation of the skin and the possibility of investing it 

 with an appearance of animation, are matters under the control of 

 the taxidermist, whose principal requirement, if these ends are to be 

 satisfactorily accomplished, is a knowledge of the poisons which 

 may safely be used to prevent the ravages of vermin ; he must also 

 possess a knowledge of anatomy and be familiar with the habits of 

 animals; and in addition to these, be endowed with the genius of the 



