EOTHENOMYS 



283 



tall-crowned, the alveolar capsule of m^ moderately protuberant 

 in the floor of the sphenorbital fissure; enamel about equal in 

 thickness on convex and concave sides of prisms; salient angles 

 opposed rather than alternating, the dentinal spaces tending to 

 be transversely confluent in consequence. Enamel pattern 

 peculiar and complex; m^ with well-developed fourth inner or 

 postero-internal salient angle, m^ with well-developed third inner 

 salient angle in most forms, but in others these structures are 

 reduced and m'- and in^ have a more normal form ; m^ variable, 



rig. 2 b. 



Tig. 5b 



Fig. 866. 

 Lower molars of Eothenomijs (1-.3 and 5 left ; 4 right). 



when most complex with four salient angles on each side, when 

 somewhat reduced with three outer and four inner salient angles, 

 and when most reduced with three salient angles on each side, 

 the precise form of this tooth being a very constant feature in 

 most of the species and subspecies now recognized. Enamel 

 pattern of lower molars much less variable ; TOj with four outer 

 and five inner angles, the general form of its anterior loop 

 " nivaloid " (Fig. 866) ; jh, and m^ each with three salient angles 

 on each side ; the opposition of the inner and outer salient angles 

 is most evident in the lower molars, where the dentinal spaces 

 throughout form a series of transverse loops or lozenges. 



