330 SYNOPSIS OF THE VERTEBRATE FAUNA OF THE PUERCO SERIES. 



ond true molars, and a set of jaws of a single broken skull, and also a left mandibular 

 ramus containing all but the canine and fourth premolar teeth. The species is dis- 

 tinguished in the ui)per series by the relativel}^ considerable development of the 

 second and third superior molars, the third having two well-developed external cusps. 

 Also by the strong development of the intermediate tubercles, and the distinctness 

 of the posterior inner tubercle of the first and second true molars. Though distinct, 

 it is only a small acute elevation of the jDosterior cingulum. The latter passes 

 round the internal base of the second and third ti'ue molars, but not the iirst. 



The ramus of the lower jaw is of moderate and uniform depth throughout, and 

 not convex below, as in M. gaudrianus. The second and third true molars have no 

 trace of the fifth cusp ; the anterior part of the fii'st is lost. There is a weak median 

 posterior tubercle on the first and second true molars, which is developed into a very 

 large obtuse heel in the third, so that this tooth is longer than either of the other true 

 molars, and reaches to the base of the coronoid process. The first premolar is not 

 relatively so large as it is in some of the species above described. Its principal cusp 

 is but little compressed, and the heel is short and transverse, and has the inner ex- 

 tremity almost cuspidate. A small acute anterior basal cusp. The second premolar 

 has anterior and posterior basal cingula oi\\y. The third is a little smaller than the 

 second. The only cingulum of the inferior molars is at the outer base of the anterior 

 half of the crown. This half is a little higher than the posterior half 



Measurements of Mamus. M. 



Length of true molar series 0245 



f anteroposterior 0075 



Diameters m. ii \ 



I transverse 0065 



^. f anteroposterior 0095 



Diameters m. m-^ 



i transverse 000 



Depth of ramus at end of m. iii 019 



" " " " " m. i OIG 



MiOCLiENUS FLOVERIANUS Sp. nov. 



This species is indicated by parts of two mandibular rami which display four of 

 the molar teeth, with which were found the following bones of the skeleton : several 

 vertebi'aj, parts of both humeri, distal end of radius, greater part of right ilium. 

 These all appear to be parts of the same skeleton. 



The first true molar has a well-developed fifth cusp which is median in position 

 and larger and lower than the fouith cusp, from which it is well separated in position. 

 There is no trace of fifth cusp on the other true molars, but there is a median poste- 

 rior of small size on the m. ii. The last inferior molar is not reduced as in some spe- 



