BY C. W. DE VIS. 101 



Though the lower teeth are in proportion to the upper unusually 

 brojxd, being scarcely a tenth narrower, the presence of similar 

 accessory processes on corresponding parts of the masticatory 

 surfaces assures us that in this instance molars of the upper and 

 lower jaws are correctly referred one to the other. 



Foimi. 



Maxillary. — P.* in the maiden state unknown. The worn 

 tooth (PI. XVI. fig. 12) is irregularl}^ subtriangular, attenuated at 

 the fore end, its ledge much dilated posteriorly, but narrow at its 

 anterior junction with the lobe, and without traces of transverse 

 ridges. Crest subcentral in front, over exterior fourth behind. 

 Mesial three-fifths of outei* surface impressed, deeply at its posterior 

 end : impressed surface with about four low vertical ribs; inner 

 surface with traces of numerous narrow vertical ribs. On the 

 intero-posterior angle remains of a cusp. Diameters 14*7 : 7 6; 

 13--1- : 7*6. The tooth is equal in length to m.^. 



P.^ unknown. 



Molars.— (V\. xvi. fig. 14). With one or more short broad 

 flame-like folds on the posterior face of each lobe within the 

 hollow triangle contained by the descending edges of the lobe; 

 not infrequently the folds become plates which- running together 

 enclose the lower part of the inner half of the triangular space. 

 The hind lobe of m.^ has no distinct processes. Traces of the 

 folds are persistent in well worn teeth with varying distinctness. 



Mandibulary. — P.'*= (PI. xvi. fig. 13) elongate, narrow anteriorly, 

 suddenly widening posteriorly; mesial diameters 11-5 x 4-3; 110 

 X 4-0; 11-1 X 5.4. Crest central, posteriorly curving down- 

 wards to the intero-posterior angle. Outer side of crown straight 

 or slightly convex, with a more or le^ss distinct mesial impression 

 bearing about three vertical ribs; inner side conchoidal posteriorly 

 with three strong ribs; anterior cusp more or less expanded and 

 well defined. 



P."^ is irregular, subelongate, tapering slowly to a pointed 

 fore end. Crest on the inner side anteriorly, on the outer 



