PETERSON : NEW CARNIVORES FROM MIOCENE OF WESTERN NEBRASKA 267 
Greatest vertical diameter of trapezoid. 
Length of Me. I .. 
Greatest transverse diameter of head Me. I 12 
Greatest length of proximal’ phalanx of’ Srd:or 4th: digit ..2.% cc tecssrecstcssseetaccces tts aertdeossneeeaeses 31 
Greatest length of median phalanx of 3rd or 4th digit . 2 
Height Of: tars0si uscuire scat cate odecr. cee ardie ost tsecead 
Transverse diameter of tarsus, approximately 
Height of astragalus 
Greatest transverse diameter of astragalus 
Greatest transverse diameter of trochlea of astragalus ... 
Antero-posterior diameter of navicular 
Greatest transverse diameter of navicular .. 
Greatest vertical diameter of navicular 
Amperospost emdr Ciamesety Olen tocu nel Onn cr racerstes sie cece sted) teecyesssceeacteet seme seemtnegtei bee sree 
Transverse diameter of entoouneitorm, Gistal end ...ce.-cc-c.cées.c.ocausseeematmeen etm inate 7 
Vertical diameter of entocuneiform... se 25 
Cynodesmus thomsoni Matthew. 
Bull. Amer. Mus. Nat. Hist., Vol. XXIII, p. 186, 1907. 
This species is represented by a considerable portion of a skeleton (No. 1529, 
Carn. Mus. Cat. Vert. Foss.) found in the upper Harrison beds on the Niobrara 
River, Sioux Co., Nebraska, and adds to our knowledge of that species. Accord- 
ing to Dr. Matthew’s statements there are apparently no hind feet with the type, 
while in the present specimen both fore and hind feet are quite well preserved 
and indicate about the same proportionate size as those of Cynodesmus brachypus. 
In fact most of the skeletal features are quite similar to those of the latter species so 
far as they can be compared. P+ is absent on both sides and considerable crushing 
has taken place at the base of the skull of C. brachypus which prevents a very accu- 
rate comparison, but it is quite evident that M# is fully as much reduced compara- 
tively as in ©! thodides Scott, and is considerably smaller than in the type of C. 
thomson and the specimen in our collection referred to the latter species. These 
and other differences of the dentition no doubt indicate more progressive develop- 
ment in C. brachypus and C. thodides so far as certain features of the dental struc- 
ture are concerned. The structure of the feet and limbs certainly approaches very 
much nearer the conditions found in Canis than is the case in Daphenodon. 
Among these may be mentioned the higher position of the deltoid crest, the less 
prominent supinator ridge of the humerus, the reduced distal end of the ulna, the 
laterally expanded supra-iliac border the concave gluteal surface and shorter ischium 
of the pelvis, the more completely grooved astragalus, the proportionally greater 
length of the metatarsals over the metacarpals, the tendency of the metatarsals to 
become appressed at their proximal ends, and the more reduced pollex and hallux. 
