140 EXTINCT AND VANISHING MAMMALS 



Barren Ground bear) may be separated into 4 more or less well- 

 marked forms, as follows: (a) the true Grizzly, Ursus horribilis 

 Ord, from the northern Rocky Mountains; (b) the Sonoran 

 Grizzly, 'var. horriaeus' Baird, probably only a subspecies; (c) 

 the Norton Sound, Alaska, grizzly, probably another sub- 

 species; (d) the very distinct Barren Ground bear, Ursus 

 richardsoni Mayne Reid. Whether or not the large Grizzly 

 from southern California deserves subspecific separation from 

 the Sonoran animal (horriaeus) has not been determined." 

 Following this preliminary statement of the case, Dr. Merriam 

 in succeeding years brought together an enormous series of 

 specimens from the larger part of the range of the grizzly, and 

 after intensive study of this material he came to the conclusion 

 that no less than 86 species of grizzly and big brown bears 

 could be distinguished as inhabiting western North America! 

 The main points of difference lie in cranial peculiarities, and 

 it is uncertain how far the species may be distinguished by 

 external characters. To many, Dr. Merriam writes, this num- 

 ber of species of grizzly bears will appear "preposterous," yet 

 the differences in cranial details are evident on close study. 

 It becomes then a matter of interpretation as to their signifi- 

 cance. Thus we do not yet know whether the five species of 

 grizzly supposed to live together on Admiralty Island will 

 actually interbreed, or whether the 15 that Dr. Merriam has 

 described as occurring in British Columbia maintain pure lines 

 of descent or hybridize. He adds: "Cranial and dental char- 

 acters among the big bears are very subtle. As a rule com- 

 parison of any two skulls of essentially the same size brings to 

 light so many resemblances that one is likely to infer a far 

 closer relationship than actually exists. This is because the 

 big bears of the genus Ursus are such a closely interrelated 

 group that the resemblances far outnumber the differences. 

 Hence the greatest caution is necessary to avoid misleading 

 conclusions." Under these circumstances a conservative 

 course of treatment may be adopted and Dr. Merriam's 

 original inclusive groups of grizzly bears be considered first in 

 a very general sense; then the various forms that he since dis- 

 tinguished may be listed with a brief statement of supposed 

 range and status. 



In a general way the more typical grizzlies inhabited the 

 West from the edge of the Plains to the Pacific, south into 



