9 



between the D- sideropelicus and the Empedocles molar is in the form of the 

 molar teeth. The species are distinguished as follows : 



Much inequality in the elevation of the extremities of the molars ; 

 lower tubercle small D. sideropelicus. 



Extremities of molars not very unequal in height ; lower tubercle 

 large B. phaseolitius. 



DlADECTES PHASEOLINCS Cope. Sp. 110V. 



This species is represented in my collection by the maxillary bones of 

 three animals, and a portion of the mandible with most of the tooth line 

 of a fourth. These fragments are of about the size of the D. sideropelicus 

 and Empedocles molaris. 



The molars possess a low cusp which is nearly in the middle of the tooth. 

 Of the lower and external cusps, the internal is the wider and more round- 

 ed ; when unworn it is as elevated as the external, but it is soon reduced 

 by attrition. The external part of the tooth is somewhat narrowed, and 

 there is no horizontal surface on either side of the median cusp, as in Em- 

 pedocles molaris. The last maxillary tooth is rather small ; preceding it 

 are eight wide transverse ones, and then two less extended transversely 

 before reaching the broken end of my best specimen. The anterior of these 

 is elongate, and may be caniniform, but its apex is lost. External layer 

 smooth ; some wrinkles round the base of the median cusp. 



The broken base of the molar bone is subrouncl and small, and shows 

 that that element is slender below the orbit. 



The portion of mandible preserved is quite deep, and is incurved at the 



symphysis. But few of its teeth are preserved, and it is not possible to 



say how long the anterior ones with subrouncl bases may have been. The 



molar whose crown is preserved does not differ materially from those of 



the maxillary series. The alveolar line does not retreat inwards from the 



external border as in Empedocles latibuccatus, resembling in this respect 



the D. sideropelicus. The external surface of the lower jaw is roughened 



by shallower and deeper small or minute pits closely placed. 



Measurements. M. 



Length of series of eleven maxillary teeth .07) 



Length of series of seven widest molars 048 



_. . , , (anteroposterior 006 



Diameter widest molar { A n .„ 



{ transverse 016 



Depth of mandible externally 050 



Width of mandible at middle 026 



It is possible that it may yet be necessary to refer this species to Em- 

 pedocles. 



EMPEDOCLES Cope. 



Proceedings Amer. Philos. Soc, 1878, p. 516. American .Naturalist, 

 April 22, 1878 ; April, 1880. 



I am acquainted with two species of this genus, E molaris* and E. lati- 



* Diadectes molaris, Amer. Naturalist, 1878, p. 565. 



