PEIMATES PEOM MADAaASCAE. 



103 



the production of this peculiar modification are seen in the accompanying diagram 

 (text-fig. 22). 



Dr. Grandidier has in his thesis on fossil Lemurs pointed out the various simian 

 characters of the mandible of Archwolemur. These need not here be recapitulated. 

 M. Grandidier regards these simian characters as evidences of specialisation, and 

 apparently inclines to the belief that they are the result of convergence, though he 

 frankly confesses he is unable to explain their occurrence. I think there is much 

 more reason for regarding these simian features as general ancestral characters and 



Text-fia;. 23, 



Cranium and mandible of Arcliceolemur echvardsi, restored. 



the condition of the recent genera of Malagasy Lemurs as specialised. But for the 

 full discussion of this question the reader is referred to the last section of this 

 memoir. The very Ape-like character of this genus may be clearly seen from the 

 accompanying restoration of the skull and mandible (text-fig. 23). 



Arch^olemue plattekhinus (Standing). (Plate XIX.) 



It was stated above that one of the skulls of Arcliceolemur exhumed at 

 Ampasambazimba presented such marked divergences from all the rest that it seemed 

 best to regard it as a distinct species, to which the n&me platyrrkiniis has been given. 

 The chief distinguishing characters of this skull will be briefly described. 



Description of Skull. 



This skull, judged by the condition of the teeth, belonged to a very old animal. 

 There is, nevertheless, an absence of the high prominent crests found in the case of 

 almost all the specimens of A. edioardsi. 



The median frontal region is much less prominently convex than in the majority of 



