230 EOCENE FAUyiE. 



Pelycodus FRUGivoRiJS Cope. 



878t«matic Catal. Vert. Eocene New Mexico, U. S. Gcog. & Geol. 6uT\. W. of UKMli Mer., Iir75, p. 14.. 

 Tomithcrium fntghorum Cope, Report U. S. Geog. & Geol. Expl. Surv. W. of lOOtli Mer., Capt. G. 

 M. Wheeler, iv, pt. ii, p. 144. Pehjcodui nunicnum Cope, BullctiD U. 8. Geol. Suit. Terrs. 1^*1, 

 p. 187. 



Plate XXV a, figs. 4-5. 



This species was not rare during the Wind River epoch of tlie Eocene 

 in Wyoming. Fragmentary jaws of six individuals of this species were- 

 found by Mr. Wortman. 



The best preserved ramus supports all the teeth posterior to and includ- 

 ing the third premolar. The last-mentioned tooth has an elevated acute 

 crown, without any anterior basal tubercle, and a very short posterior heel. 

 The fourth premolar is very stout; its cusjjs are not much elevated, and 

 the heel is short. The anterior basal tubercle is quite small. All of the- 

 tnie molars have a second cusp in front of the anterior tubercle, but it is 

 quite small, excepting on the first, where it is more distinct. The external 

 crescents of all the molars are well defined, but the posterior does not 

 inclose the crown behind with an extension of its horn. The last molar 

 is a little longer than the others, and its posterior border is produced into 

 two cusps. A simple raised border is found here in the typical specimen or 



P. frugivorus. 



* Measurements. 



M. 



Length of molar series from third premolar, inclusive 0228 



Length of true molars 0150- 



„ „„ , (anteroposterior OOoO 



Diameters of first true molar } . nnoa 



( transverse 0038 



„. „, , (anteroposterior 00(55 



Diameters of last true molar? . nnm 



< transverse 0040 



Depth of ramus at Pm. Ill 0095 



Depth of ramus at last true molar 0095 



The character of the last molar above mentioned distinguishes the 

 four specimens of this species where that tooth is preserved, from the 

 type of P. frugivorus. I originally looked on these as representing a dis- 

 tinct species on this account, and called it P. nunknum, but further investi- 

 gation will be necessary in order to asceilain whether this course was 

 justifiable or not. 



A series of superior molar teeth accompanying the lower jaws and 

 bones of PUsiardomys ddkatior, so strongly resembles those of Pelycodus 



