G. NATURAL HISTORY AND ZOOLOGY. 335 



Mr. Allen's paper embraces a list of the species of North 

 American Sciuridce which he considers permanent, and among 

 the true squirrels he allows but five that are permanent where 

 Audubon gives twenty-four. He, however, recognizes in ad- 

 dition seven geographical varieties, making the whole num- 

 ber of permanently distinct forms twelve. Of flying-squirrels 

 he allows but one species ; of the genus Tamias, or the ground- 

 squirrels, he gives three; of the Spermopkilus, eleven; of the 

 prairie-dogs, two ; and of the true marmots, three making 

 twenty species in all. Proc. Bost. Nat. Hist. JSoc, XVI., 1 874. 



RELATIONSHIP OF AMERICAN DEER TO THEIR BRITISH 



ANALOGUES. 



The precise relationships of certain species of American 

 deer to European analogues the moose, the reindeer, and the 

 elk especially have been the subject of critical consideration 

 on the part of naturalists for many years past, some maintain- 

 ing that they are identical, and others that they are distinct. 

 None has given the matter more attention than Judge Caton, 

 of Illinois, who for many years has had in his large park near 

 his residence at Ottawa specimens of nearly all the American 

 species, where he has carefully studied their habits. 



Quite recently Judge Caton visited the North of Europe 

 for the purpose of examining the Old World forms in life, 

 and has satisfied himself, from careful study, of the absolute 

 identity of the moose and the caribou of the two continents, 

 and of the very close relationship between the American elk 

 and the European stag. One character of much importance 

 in the deer consists in the presence and shape, or entire ab- 

 sence, of a peculiar gland on the metatarsus of the hind-leg, 

 this being indicated, if present, by a tuft of hair of a particular 

 shape, and varying with the species. The American repre- 

 sentatives of the moose and caribou do not possess such a 

 gland ; and as Dr. John Edward Gray asserts its existence in 

 the European species, Judge Caton at one time inferred a 

 specific distinction. He now finds, however, that equally 

 with the American they are destitute of the gland, and that 

 there is absolutely no point in which they can be separated. 



In regard to the relationship between the European stag 

 and the American elk, he finds the principal difference to be 

 in the smaller size of the former. Fossil remains, however, 



