J. B. Hatcher — Recent and Fossil Tapirs. 173 



1. Nasals longer than their combined width, and applied to one 



another throughout the greater part of their length, each 

 usually ossified from a single center E. bairdii. 



2. Nasals broader than long, more or less separated by an ante- 



rior prolongation of the frontals, each usually ossified from 

 two separate centers _ M. cloici. 



B. Ossification of mesethmoid cartilage never extending much 

 in front of middle of nasals. Superior border of maxillaries low, 

 and widely separated from each other. Premaxillaries long and 

 acute posteriorly _ Tapirus. 



1. Premaxillo-maxillary suture bisecting alveole for canine. Pre- 



maxillary deeply embraced by superior and inferior 

 branches of the maxillary. Sagittal crest broad and low. 

 Nasals broad and long, sup. pm. 2 molariform . . T. indicus. 



2. Premaxillo-maxillary suture passing in front of alveole for 



canine. Premaxillary not deeply embraced by superior 

 branch of maxillary. Sagittal crest sharp and high. Nasals 

 broad aud short. Sup. pm. 2 molariform T. terrestris. 



3. Premaxillo-maxillary suture passing in front of alveole for 



canine. Premaxillary scarcely at all embraced by superior 

 branch of maxillary. Sagittal crest sharp and low. Nasals 

 long and narrow. Sup. pm. 2 submolariform . . T. roulini. 



Tapirus, Brisson (1756) Regne Anim., p. 118. 



Syn. Rhinochoerus (Gray), Rhinochoerus (Wagner) in part, 



Hydrochoerus (Erxleben) in part, Sys. Reg. An., 1777, p. 191. 



Tapirus roulini Fischer.* 



Syn. T. pinchacus, T. villosus, T. leucogenys, T. cenigmaticus and 

 Tapir pinchaque. 



A skull and the sup. dentition of the present species are 

 shown in fig. 2, plate Y, and figs. 2 and 2a, plate TV, drawn 

 from No. 204 in the Yale osteological collection. T roulini 

 is the smallest and least specialized of all the recent Tapirs. 

 The skull is low, narrow and flat, the nasals are long, pointed, 

 coossified, and posteriorly, they are but little lower than the 

 frontals. The premaxillaries are scarcely at all embraced by a 

 superior arm of the maxillaries and the latter projection is not 

 higher than the embraced portion of the premaxillary. The 

 ossified septum does not extend in front of pos. border of 

 nasal opening. The cavity for lodgment of cartilaginous air 

 sinus is deep, but extends but slightly upon the base of 

 the nasals. The floor of the orbit is shallow but deeper 

 than in T. indicus. The foramen magnum is absolutely and 

 relatively larger than in any of the other species. Sup. pm. 1 



* Fischer's Synops. Mam. Add., p. 406. 



