434 \V. K. GREGORY NOTHARCTUS AND LEMUROIDEA 



Subfamily Chirogaleinse 



Size usually small. 



Foramen lacerum medium ("carotid foramen") open (except Myoxi- 



cebus). 

 Palate extended to or behind m^. 

 Brain-case wide ; no sagittal crest. 

 Genera: Microcehus, Cheirogale, Atilileinur {Opolemur) , 2Iyoxicehus 



(Hapalemiir) . 



Sill )f ami ly jVlegaladapina? 



Size very large. 



Foramen lacerum medium roofed over. 



Palate extended behind m^. 



Skull excessively elongate. 



Brain-case small, much reduced in width, witli sagittal crest. 



M^ large. 



Genus : Megaladapis. 



Family Indrisidse 

 Pleistocene and Ik'cent of Madagascar. 



pi p o 



Dental formula: I—' C— ' Pr — x' M-^- 



1 1 Z o o 



Lower incisors styliform, procumbent; upper incisors usually persistent, 



sometimes large. 

 Lower canines resembling the incisors. 

 Upper canines fairly large. 

 Po compressed opposing upper canine. 

 Lacrymal less extended on face; laci^nial foramen either just in front 



of orbit (most Indrisinge) or marginal (PalcEopropilhecus, Avchseo- 



lemuringe). 

 Brain-case expanded {except Pala-opropithecus) . 

 Angle of mandible much expanded; symphysis much prolonged and 



sloping. 

 Upper molars large, quadritubercular ; m'^ small ; m., with third lobe 



reduced or absent. 

 Bullae typically much expanded and completely inclosing tympanic an- 



nulus (except PaJceopropithecus) . 



Subfamily Indrisinfe 



Medial upper incisors and lower canines small or of moderate size. 

 Two lower premolars. 



