362 



University of California Publications in Geology 



[Vol. 12 



Comparative Measurements op the Teeth — {Continued) 



Pliauchenia? 

 merriami, 



Type, 

 no. 23483 



Camelus 

 dromederias 



16 mm. 



Length of diastema posterior to C 28 mm. 



Length of diastema posterior to 37+ 



C, upper, anteroposterior diameter 23 



C, lower, transverse diameter al4 



Pj, anteroposterior diameter 20.7 



Pj, transverse diameter 10.5 



Length of diastema anterior to canine absent 

 Length of diastema posterior to canine.... 33 



Length of diastema posterior to P; 55 



44 



27 



20.5 



16 



12 



10 



26 



66 



a, approximate. 



General comparison. — The specimen agrees with Procamelus and 

 more recent forms in the loss of the first and second upper incisors. 

 It is decidedly larger than any of the types described under Procamelus 

 and ditfers from these forms in the evident reduction of its premolars. 



Except in size the specimen bears little resemblance to Alticamelus 

 as seen in A. procerus of the Snake Creek. The lower jaw is noticeably 

 elongate anterior to the cheek tooth series when compared to the fig- 

 ures of the relatively short-proportioned jaw of A. procerus and A. 

 giraffvims.*^ Both upper and lower teeth are considerably more 

 developed than in these forms. Dr. IMatthew stating that the lower 

 teeth of A. giraffinus are even smaller than those of the living camel 

 and indistinguishable from those described by Dr. Leidy as Procamelus 

 rohustus. A comparison of the length of the limb elements points to 

 the Eden form being larger than A. procerus. Data on the correspond- 

 ing elements of A. giraffinus are unavailable. It is, however, evident 

 that the specimen cannot be referred to the genus Alticamelus. 



The fossil differs very markedly from Camelops, as seen in the 

 Rancho La Brea C. h ester nus*° in the following characters: (1) the 

 lack of an actual diastema between the outer incisor and canine of the 

 lower jaw, versus the broad diastema figured in the type specimen 

 of the Rancho La Brea form of Camelops liesternus. (The presence 

 or absence of this diastema may possibly be somewhat dependent on 

 age, as it is reduced in other specimens of the Rancho La Brea form) ; 



(2) the enlarged first premolar in both jaws versus its total absence; 



(3) the considerably larger size and much greater strength and 



•18 Matthew, Wm. D. Mem. Am. Mus. Nat. Hist., vol. 1, 1901. 

 49 Merriam, John C. The Skull and Dentition of a Camel from the Pleistocene 

 of Eancho La Brea. Univ. Calif. Publ., Bull. Dept. GeoL, vol. 7, pp. 305-323, 1913. 



