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BULLETIX 16 9, UNITED STATES XATIOIv'AL MUSEUM 



In short, C. corrugatus and C. Jerox are not distinguishable on any 

 correct factual basis derived from the known specunens, and they 

 must be considered synonymous, the name C. jerox being retained for 

 the species. The value of the coefficient of variation maj^ be taken 

 as indicative of the degree of variability to be expected in the same or 

 analogous dimensions in species of this genus. 



The relationships of the genus Claenodon as a whole have been 

 widely discussed and are summed up so thoroughly by Matthew 

 (Pale. Mem.) that no details need be given here. It is a typical 

 arctocyonid, very close to Arctocyon itself, and in its larger species, 

 at least, forerunner of the lower Eocene Anacodon, after which the 

 line evidently became extinct. Relationship with the bears has often 

 been suggested and was favored by Dr. Gidley, but it is almost cer- 

 tainly erroneous. There is very little question that bears developed 

 from dogs during the Middle or Later Tertiary and that the limited 

 convergence to them shown by Claenodon involves habitus characters 

 only and denotes a convergence in food and other habits, but not 

 any special affinity. 



Figure Z6.— Claenodon feroz (Cope), tentatively referred specimens from the Melville (Fort Union No. 3): 

 a, U.S.N.M. no. 61.56, left M2; 6, Princeton Univ. no. 13755, right Mi, probably from Loo. 44; c, same data 

 as 6, left Ma-3 and heel of Mi; d, same data as b, right M'-^, M' broken; e, Princeton Univ. no. 13756, left 

 M'-', Ml broken, probably from Loc. 49. All natural size. 



CLAENODON FEROX (Cope, 1883) 



Figure 36 



U.S.N.M. no. 6156, a left^^ Mg and some other fragments, from 

 well up in Fort Union No. 3, was tentatively referred by Gidley (1919, 

 pp. 545-547) to Claenodon Jerox, with the reservation that better 

 material might prove that a new species is represented. Gidley noted 

 several distinctions from characteristic C. Jerox of the Torrejon but 

 suggested that all could be due to individual variation, except, perhaps, 

 the fact that in the Montana specimen the talonid is narrower than 

 the trigonid. This, however, is also within the range of variation of C. 



" Gidley, 1919, p. 545, says "right", obviously a lapsus calami. 



