122 PROCEEDINGS OF THE ACADEMY OF [1894. 



Color and form. — The living specimens of this bear which have 

 been under observation were of similar color, in winter pelage a rich 

 cinnamon brown. The tw^o which have lived in the Zoological Gar- 

 den for more than one season, became in summer of a pale bleached 

 brown, or Isabella color. The skin in the Academy's collection, be- 

 longing to skull 3, 308 is almost flaxen. 



The size of the four living specimens was nearly the same, about 

 5 ft. , 6 in. from nose to tail. 



The claw is short and curved as in amerieanus. 



The great anterior width of the zygomatic arch and the hollow 

 forehead are faithfully reflected on the outer surface in these bears, 

 the sharp drop between the eyes and the laterally pinched-in muzzle 

 giving them a peculiar and unmistakable, fox-like look. 



Identity and relationship. — In studying out the correct assignment 

 to be made of these bears, a considerable mass of material has been 

 examined, including, through the kindness of Mr. Oldfield Thomas, 

 the series of arctos and other bears in the British Museum ; and also 

 the collection of the Royal College of Surgeons, London. 



The great range of individual variation in most species of Ursns, 

 is well known : in my own observations amounting, in the leading 

 proportions of the skull, to over twenty per cent, in arctos; sixteen 

 per cent, in amerieanus, with a somewhat smaller range in Jiorri- 

 hilis. 



The table following shows the main standard measurements of the 

 skull in cinnamomeus, arctos, Jiorribilis and amerieanus, arranged 

 for convenience of comparison in the descending order of proportional 

 breadth ; the skulls selected for measurement pretty well covering 

 the extreme range in both directions. The proportions of zygomatic 

 breadth and length of hinder upper molar are expressed in 

 thousandths of the basilar length : — 



