rYNOPTi:RUS. 



589 



Upper incisors subtereto, cro-wii not peculiarly differentiated, 

 slightlj flattened antero-posteriorlj-, i" slightly but. distinctly 

 shorter than i' ; lower incisors subequnl in height, but i, a little 

 heavier in bulk than i,, crown somewhat flattened laterally (its 

 antero-posterior distinctly greater than its transverse diameter), 

 cutting-edge simple or with a faint median notch. Diastema i^-c 

 subequal to or a little narrower than c-p\ Upper and lower 

 canines short and stout, with a distinct secondary cusp near middle 

 of inner edge, produced by a prolongation of cingulum ; anterior 

 surface of crown perfectly smooth (no vertical groove), p' rudi- 

 mentary, but not deciduous, terete, scarcely as high as cingulum of 

 canine ; p^ about twice to four times the bulk of i^. p'-m' and Pj-m^ 

 very similar to corresponding teeth of Rousettiis, but outer and 

 inner ridge of p^ always separated at tip (though connected by a 

 commissure at base), ridges of p^ not quite completely fused, and p^ 

 and m^ (or the latter only) often with a more or less conspicuous 

 surface cusp (see next paragraph), as in some species of Dohsonia. 

 lUj small, subequal to or rather a little larger than p,. 



Surface cusp in m, and p^ (fig. 49). — The genus taken as a whole 



Fig. 411.— A. iipi^er riglii, E, lower left tooth-row of Cunopterus !>phinx 

 ti/ihcec/iciliis {d.l.b.lid). 

 A', B', con-esponding tooth-rows of Cijnopierus princeps 

 (U.S. National Museum, no. 141274, paratype of .species), 

 f (linear). 



exhibits any gradation, from complete absence of a surface cusp in 

 m, and p^, through a barely perceptible trace of such cusp in m or 

 both in nij and p^, or a small but quite distinct cusp in m, or both 

 m, and p^ (fig. 49 B), to a perfectly well-developed or even large 

 cusp in both teeth (fig. 49 B'). But there is in this respect decidedly 

 a difference of degree between C. sphinx, hraclnjotis, and major on the 

 one hand, and C. horsfiehli, harpax, and pAnceps on the other. As 

 the latter three species are further distinguished by rather shorter 

 and broader, more subrectangular or subquadrate cheek-teeth, the 

 genus may conveniently be divided into two sections, the C>/nnpteriis 



