186 BULLETIN OF THE 



and some other characters of the U. ft vox. This similarity of skulls," he 

 says, " is the more remarkable, as no two bears can be more distinct from 

 each other than the species above named,* which have such similar skulls, 

 showing that similar skulls do not always imply very nearly allied or 

 doubtfully distinct species." 



The bears have ever been a perplexing group, and accordingly the 

 opinions advanced by different authors respecting the number of species 

 vary widely. Severai high authorities consider the land bears of Northern 

 North America, Northern Asia, and Europe as forming but one, or at 

 most two, species, among which are Blainville and Middendorff, the 

 latter of whom, with access to a large amount of material, has especially 

 and most minutely investigated the subject. Other authors are disposed 

 to allow a much greater number. But, unfortunately, their statements in 

 reference to the differences that should distinguish them are frequently 

 contradictory. Dr. Gray recognizes eight f in his recent monograph, with 

 numerous " varieties " and " subvarieties " of each. Of the Ursas arctos, 

 or brown bear of Europe, he describes four varieties, and of the first of 

 these eight subvarieties, to all of which he gives distinctive names. All 

 of these are chiefly based on variations in color, the teeth, or the skull, 

 although he states in the same paper that characters based on the latter 

 are to a considerable extent unreliable for even the determination of 

 species. J Nilsson, in his Scandinavian Fauna, distinguishes six varieties 

 that differ widely in color from Sweden alone. A careful study of Mid- 

 dendorlF's tables of measurements, embracing souk; fifty specimens of bears 

 from Europe and Asia, show how very extended is the range of variation 

 in osteological and external characters, and how irregular is its nature. 

 Schrenck has also called attention to the. great variation in the size of the 

 tuberculated grinders in the bears of Northern Asia. — a character which 

 is unfortunately made the principal basis of Dr. Cray's specific and sub- 

 specific distinctions. Dr. Gray himself mentions that there are consider- 

 able variations in the series of skulls of American bears in the British 

 Museum; particularly in the amount of depression in front, of the orbits. 

 His several tables of measurements of skulls that he himself refers to one 



* In respect to this poi.it I shall soon show tint naturalists high in authority do not 

 agree with Dr. Cray in regard to the great distinctness claimed by him for those specie-. 



t It seems to me that no recent writer has heen guilty of greater inconsistency than 

 i< exhibited by the author of the monograph on the Ursulas above cited; for after 

 calling attention to the variability of craniological characters, and their consequent 

 unreliability as spocinY, distinctions, he adopts some of those that can he readily shown 

 t,, be the most trivial— even manifestly so from his own paper — as the basis of 

 his classification of his species and varieties. So difficult is it apparently to overcome 

 long-established habits of thought and modes of reasoning. 



t See preceding page. 



