PEIMATES PEOM MADAGASCAE. 117 



Table 14. — Giving dimensions (in millimetres) of mandible of Megaladajns grandidieri. 



Prom condyle to tips of incisors 



From condyle to summit of symphysis 



From lower end of symphysis to a line joining inferior angles .... 



From coronoid process to inferior angles 



Maximum distance from condyle to inferior angle 



Length of series of molars and premolars 



From posterior edge of last molar to postero-inferior angle 



From condyle to posterior. edge of last molar 



Length of symphysis 



Distance between coronoid processes 



Distance between condyles 



Distance between inferior angles 



Breadth between rami behind third molars 



Space occupied by dental series from median incisor to third molar 



Space occupied by two premolars , 



Thickness of jaw at level of first molar 



Height of jaw at level of first molar (including tooth) , 



Subfamily L E M u E i N ^. 

 Genus Lemuk. 



Of the existing Malagasy Lemuroids (if we exclude the aberrant CMromys) the 

 members of the genus Lemur bear the least resemblance to the higher Primates. At 

 the same time their affinities with the scattered members of the family of Lemuridse 

 in the continental areas of the Old World are obvious. Many of these sporadic genera 

 of Lemuridee show evidence of specialisation. As illustrating this statement reference 

 may be made to Loris, Nycticehus, and Tarsius. How far the similarities between the 

 various genera are the result of convergence or specialisation along similar lines due to 

 similar habits and conditions, it would be difficult at present to determine. There is 

 evidence in the case of the Indrisine group of a strong tendency to the production of 

 some of the distinctly " Lemuroid " features among the surviving members of a family 

 whose extinct representatives were evidently descended from ancestral forms with 

 strong Simian affinities, if not, indeed, from progenitors which can only be described 

 as Apes. 



A comparison of Indris, Propitliecus, and Jvahis with such forms as ArcJiceolemur and 

 Iladrojnthecus leads to the belief that the long muzzle, flattened brain-case, weak 

 upper incisors, and frail mandible are in the case of the extant genera secondarily 

 acquired. Although in the case of the Lemurinse the evidence is as yet incomplete, no 



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