CREODONTA. 345 



DissAcus NAVAJOviDS Cope. 



American Naturalist, 1881, p. 1019. Mesonyx navajoviits Cope, Proceed. Amer. Philos. Soc. 1881, p. 484 



(September 30). 



Plate XXV c; iig. 1. 



Smaller than the two known species of" Mesonyx, and with the crowns 

 of the molars more compressed and the blades of the heels of the inferior 

 series more acute. Molars seven, the first one-rooted. Last molar with a 

 cutting heel like the others, and with the penultimate, with a rudimental 

 anterior inner cusp. All the molars with an anterior basal tubercle except 

 the first, second, and third. No basal cingula. Principal cusp elevated and 

 compressed, as in the premolars of Oxycena. Enamel minutely rugose. 

 Mandibular rami and inferior canine teeth compressed, the angle of the lat- 

 ter not inflected. 



Measurements. 



u. 



Length of inferior molar series 078 



Length of premolar series 046 



Length of base iv premolar 010 



Pm. iv, elevation of cusp 008 



Length of ii true molar .012 



Elevation of true molar 010 



Width of heel of true molar 005 



Depth of ramus at M. ii 020 



Diameter of base of crown of canine 009 



This species was a little larger than the red fox. Its remains were 

 found by Mr. D. Baldwin in Northwestern New Mexico. 



DiSSACUS CARNIFEX Cope. 



American Naturalist, 1882, p. 834 (October 5). 

 Plate XXIV g; figs. 3-4. 



This creodont diff"ers from its only congener in its greater size, and in 

 the presence of an anterior basal lobe on the third inferior premolar. This 

 is wanting in D. navajovius. As compared with the latter the six inferior 

 molars are as long as its seven, and the mandibular ramus is much deeper. 

 Like it the Pm. iv and the true molars have an anterior basal tubercle; and 

 the last two true molars have an internal supplementary cusp. After the 

 Sarcothraustes antiquus, the largest flesh-eater of the Puerco, and about equai 

 in dimensions to the coyote. 



