906 THE JOHN DAY FAUXA. 



anterior tubercle is small, and is set well inwards. The first tubercular has 

 a very oblique external border, owing to the rapid contraction posterioily 

 of the maxillary bone. The two external cusps have the usual direction, 

 so that it results that the anterior external angle of the crown is very jjro- 

 tuberant, much more so than in T. ultlgeMis. Moreover, the external basal 

 cingulum is not defined at the base of the posterior cusp, as it is in T. aUi- 

 genis. For the rest this tooth resembles the corresponding tooth in tl;e 

 latter species, except as to size. The middle of the crown is occupied by 

 a deep valley, which is bounded within on the anterior border of the crown 

 b-S' a subtrihedral tubercle, which does not send a ridge back to the poste- 

 rior border, as is usual in dogs. The internal cingulum is wide and flat. 

 The second tubercular molar is relatively small, having about half the 

 grinding surface of that of the corresponding tooth of T. altigenis. The 

 posterior external cusp is a mere rudiment, and the cingulum is not well 

 defined. The internal tubercle and cingulum are confounded in a uniform 

 surface within the median concavity. The rugosity characteristic of the 

 T. altigenis is little visible in this specimen. 



Measurements. 



M. 



Leugth of superior dental series on liase from canines 067 



Length of bases of true molars 014 



Diameters of sectorial <'''"f''^°I"'^*"'"^ ^JJ 



( transverse in front Oil 



T^. . f i: i i 1 ^ auteronosteriiir ..; 012 



Diameters ot tirst true molar < ' 



( transverse at middle 015 



^,. ^ i- 1 . 1 ^anteroposterior 00.5 



Diameters of second true molar ^ '^ 



( transverse 010 



From the John Day Bad Lands, Oregon. J. L. Wortman. 



Temnocyon coryph^us Cope. 



Proceedings Academy, Philadelphia, 1S79, p. 180. Figure 2, in Proceedings American Philosophical 

 Society, 1880 (February). Canin harlshorniantis Bulletin U. S. Geol. Survey Terrs., V, 1879, p. 

 58; not Cope Anuual Report U. S. Geol. Survey Terrs., Iti72 (lb7:!), p. TiOG. 



Plates LXXI; LXXIn, tigs. 1-7; LXXIIa, figs. 4-7. 



That this dog was the most abundant species of the Oregon Miocene 

 is indicated by the fact that the following material representing it is now 

 in my collection: Seven crania, several of them with mandibles and more 



