']6 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 1 28 



these forms, however, shows any tendency toward a diastema in the 

 premolar series as long as that in C. arapahovius. The jaw, moreover, 

 appears to be relatively slender, taking into consideration its maturity 

 as evidenced by tooth wear. 



MEASUREMENTS IN MILLIMETERS OF DENTITION IN TYPE SPECIMEN OF 



Camelodon arapahovius, a.m. no. 14604 



Length of lower cheek tooth series, Pa-Ma, inclusive 51.0 



Lower molar series, M1-M3, inclusive 27.1 



Pa, anteroposterior diameter : greatest transverse diameter 6.4 : 2.0 



P3, anteroposterior diameter : greatest transverse diameter 6.7 : 2.3 



P4, anteroposterior diameter : greatest transverse diameter 7.0 : 2.9 



Ml, anteroposterior diameter : transverse diameter of talonid 6.8 : . . . 



Ma, anteroposterior diameter : transverse diameter of talonid 8.3 : 5.7 



M3, anteroposterior diameter : transverse diameter of trigonid 12.8 : 5.3 



MALA0UIFERUS,4o new genus 



Type. — Malaquiferus tourteloH, new species. 



Generic characters. — Orbit large and cranial portion of skull elon- 

 gate. Enamel of cheek teeth highly rugose. P* without labially di- 

 rected styles. External styles of upper molars weak but ribs out- 

 standing. Upper molars nearly rectangular, transversely elongate, and 

 not oblique. M^ and M^ of equal size. Protocone strongly bilobate 

 posteriorly, at least in M^. 



Discussion. — Malaquiferus is clearly related to Oromeryx and 

 Protylopus, but differs rather noticeably in the striking shift in 

 emphasis from styles to ribs in the upper molars. These teeth are 

 nearly rectangular, transversely elongate, and not so oblique as in 

 Oromeryx. There is much less disparity in size between succeeding 

 molars in Malaquiferus so that M^ is relatively much smaller than in 

 Oromeryx or Protylopus, being scarcely distinguished from M^ in 

 size and form. There appears to be no cingulum around the lingual 

 margin of the protocone and metacone in any of the molars, although 

 there is a prominent style or pillar lingually between these cusps in 

 each. An additional feature noted is the comparatively large orbit and 

 more elongate cranial portion of the skull than in Protylopus. Mala- 

 quiferus bears a strong resemblance to Oromeryx, and evidently to 

 Protylopus, in the distinctly rugose tooth enamel and in the bilobate 

 character of the posterior portion of the protocone in the upper molars. 



*° From Latin mains, bad ; aqua, water ; and ferus, wild animal. In allusion to 

 its occurrence in the Badwater region. 



