12 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.63. 



PRONOTHODECTES, new genus. 



Genotype. — Pronothodectes matthewi, new species. 



Generic chaymcters. ^General characteristics similar to Nothodectes ,. 



but less advanced in development. Dentition: I — '-, c —'- ^ 



1 1 or 



pms — '-, ms -. Cusps and cuspules of upper cheek teeth low and 



rounded; no mesostyles; no definite hypocene or posterior internal 

 ridge, although the protocone is lengthened and shghtly angulate in 

 this region. Trigonids of lower molars relatively high with paraco- 

 nids distinct, but closely connate with the metaconids, and with the 

 nearly equal summits of the metaconids and protoconids relatively 

 more nearly approached than in Nothodectes. Pj and pj small and 

 single rooted p^ with simple high and very short protoconid and short 

 single cusped heel. Upper p* submolariform with metaconid equal 

 in height to paraconid and but little separated from it by a very 

 shallow notch. 



PRONOTHODECTES MATTHEWI, new species.' 



Plate 3, Figure 2. 



Type. — Three upper cheek-teeth (p* to m^) of the right side in a 

 fragment of the maxillary. (Cat. No. 9547, U.S.N.M. Coll.) 



Paratypes. — Greater portion of a left lower jaw carrying the en- 

 larged incisor (broken), pms j^ ^ 4 ^^^ ^s i 2 3 (Cat. No. 9332, U.S. 

 N.M. Coll., see pi. 4, fig. 3; and two upper incisors. (Cat. Nos. 10005 

 and 10044, U.S.N.M. CoU.) 



Locality and horizon. — -All from "Gidley Quarry, " near top of Fort 

 Union "No. 2," Sweet Grass County, Montana. 



Specific characters. — Size about one-fourth smaller than Nothodectes 

 gidleyi. P* to m^ = 5.9 mm.; mi to m3 = 7.3 mm.; p* relatively nar- 

 rower and all molars, both upper and lower, relatively wider than in 

 species of Nothodectes. P* with paracone and metacone subequal 

 but closely twinned; hypocone ridge only incipiently developed; no 

 diastema in lower jaw; a very much reduced canine indicated; p, 

 slightly smaller than Pj; both these teeth simple and single rooted. 

 Trigonid of mj with the three cusps about equal in size, their unworn 

 summits forming a nearly equilateral triangle. 



Pronothodectes belongs unquestionably to the Plesiadapidae, as de- 

 fined by Matthew, and seemingly is so closely related to Nothodectes 

 that the generic characters based on the material in hand can not be 

 sharply •defined. 



' I take pleasure in naming this species in honor of my good friend Dr. W. D. Matthew, who has 

 done such splendid work, especially in connection with problems pertaining to the study of the early 

 primates. 



