88 



DE. H. P. STANDING ON SUBFOSSIL 



The Occipital Region. — The occiput of Mesopropithecus is but little inclined from 

 the vertical in the adult skull, though a young specimen just cutting its canines has a 

 much inclined occiput, the plane of the foramen magnimi making an angle of but 35° 

 with the horizontal plane. 



In the adult the conformation of the occipital region shows a striking resemblance 

 to that of Archceolemur edwardsi. The foramen magnum is circular or slightly 



Text-fig. 15. 



Skull of }'oung (A) Mesopropithecus compared with that of (B) Avahis. 



elongated in a horizontal direction. The occipital condyles are widest near their 

 upper extremity, the line of greatest transverse convexity here running obliquely 

 outwards and upwards. In a young skull the median convexity for the lodgement 

 of the central lobe of the cerebellum is strongly marked as in recent genera, but in 

 the adult the condition approaches that of full-grown specimens of Archceolemur 

 edwardsi. The paroccipital processes also resemble those oi Archmolemm\ being blunt 

 and pyramidal in form. The lambdoidal crest is prominent, running backwards in 

 a horizontal direction in a manner closely analogous to the condition seen in 

 Archceolemur. The supraoccipital enters to but a small extent into the roof of the 

 skull, resembling in this the majority of the higher Apes. Among the existing genera, 

 Avahis comes nearest to the fossil in this respect. The lambdoidal suture has a feeble 

 anterior convexity, the curvature being approximately parallel to the lambdoidal crest. 



The Parietal Eegion. — In the parietal and frontal regions further resemblances to 

 Archceolemur are noticeable. The brain-case is globular or rather pyriform; it is 

 more elevated than in either Indris or Propithecus and narrower in the postorbital 

 region. The parietals form a more considerable part of the roof of the brain-case than 

 in either of these recent genera. 



The upper lines of attachment of the temporal muscles are either closely approxi- 

 mated along the middle line, or actually meet, forming a more or less strongly marked 

 sagittal crest. This crest is continued forward as far as the coronal suture, when it 



