No. 7.] NIMRAVIDiE AND CANIDJ3 OF THE MIOCENE PEEIOD. 173 



serrate cutting edge is presented almost entirely inwards. The interno- 

 anterior face of the crown is flat, and has a low shoulder at the base. The 

 molars have the proportions of those of N. gomjpJiodus, differing only in 

 their smaller size, which is very apparent, as can be seen by the measure- 

 ments. The first (third) premolar is a little longer on the base than high, 

 has no anterior tubercle, and has a short cutting basal heel. The fourth 

 premolar has subequal anterior and posterior basal cutting lobes, and the 

 base is longer than the elevation of the median cusp. The sectorial tooth 

 has a short cutting heel, but no trace of inner tubercle. The anterior lobe 

 is as long as the median, but not so high. It overlaps the fourth premo- 

 lar as far as the base of the median cusp. No incisor teeth are pre- 

 served in the specimen. Tubercular small. 



Measurements of sTcull. 



M. 



Deptli of ramus at diastema 020 



Depth of cliiii 027 



Elevatiou of inferior canine 016 



Diameter of inferior canine at base 010 



Length of inferior diastema 014 



Length of inferior molar series 053 



Length of third premolar 014 



Elevation of third premolar 010 



Length of fourth premolar 016 



Elevation of fourth premolar 013 



Length of sectorial 022 



Elevation of median cusp of sectorial 015 



One specimen, from the John Day Valley, Oregon, found in the Truckee 

 formation, by J. E. Wortman. 



COLOKEODON KYDERANUS Sp. nOV. 



Eepresented by a nearly complete skull, without lower jaw. These 

 indicate the third and smallest species of the genus. The specimen be- 

 longed to an adult animal, as indicated by the condition of the last two 

 molar teeth. 



Besides the small size, two characters may be cited as distinguishing 

 this species from those already known. Eirst, the temporal ridges con- 

 verge very gradually, so that the sagittal crest does not appear anterior to 

 the line of the otic bullae, posterior to which point the skull is broken 

 above. Second, the face is constricted immediately posterior to the po- 

 sition of the fundus of the alveolus of the canine teeth. The position of 

 this alveolus is prominent, and occupies the superior half of the maxil- 

 lary bone, which is excavated beneath it. This excavation is bounded 

 behind by the infraorbital foramen. The lachrymal bone presents an 

 angle into the orbit. The latter is open posteriorly, but the opposing 

 processes approach each other. The zygomata are slender. -. The enamel 

 of the molars is slightly wrinkled. 



