168 



GREGORY: NOrHARCTUS, AN AMERICAN EOCENE PRIMATE 



brain-cavity are shown in several fragmentary skulls, especially Nothardus venticolus, Amer. Mus. No. 

 14656, A^. osborni, No. 12569, and A^. matthewi, No. 13030. 



As compared with the endocranial casts of Lemur varius, L. jullyi,^ Propithecus and Alouatta, the 

 brain of Nothardus had very small, narrow cerebra, with poor frontal lobes. Such feeble sulci of the 



R Fa Fp U Lt 8 h 



Lf C 10 



Fig. I. 



Pm 3 6 



Fig. III. 



Fig. 63. Endocranial cast of Adapts parisimtsi.s. After Neumayer. Twice natural size. 

 8, fossa subarcuata 



cerebra as were present did not show through the membranes enough to leave any well-marked grooves 

 on the cast, although the superior longitudinal sinus is indicated by a prominent median crest; and there 

 seem to be vague indications of the sulcus intraparietalis. The median lobe of the cerebellum was 

 exposed above, as in Lemur. The lateral lobe, filling the small subarcuate fossa in the periotic was also 



1 Cf. Elliot Smith, 1908, Trans. Zool. Soc. London, XVIII, part 2, p. 165, fig. 



