166 MR. ST. GEORGE MIVART ON MICRORHYNCHUS. [Mar. 13, 



fifth digit ; pollex short and placed far back ; hallux very long and 

 covered with hair ; tail long, or very short and rudimentary ; internal 

 condyle of the humerus perforated ; carpus destitute of an os inter- 

 medium ; tarsus short ; first upper molar with four large and four 

 small prominences, no internal cingulum ; last upper molar with two 

 large anterior cusps and three very small posterior prominences ; each 

 lower incisor with its outer surface longitudinally grooved ; lower 

 premolar much antero-posteriorly extended ; first lower molar with 

 four or five cusps ; last lower molar quinquecuspid ; a paramastoid 

 process ; no malar foramen ; lachrymal foramen very near margin of 

 the orbit ; masseteric surface of malar wide and ridged ; a process 

 depending from zygoma just in front of, and external to, the glenoid 

 surface ; a postglenoidal foramen ; anterior palatine foramina very 

 large ; mandibular symphysis very long ; condyle rounded, not trans- 

 versely extended ; articular surface prolonged somewhat down the 

 back of ascending ramus; digastric fossa deep. 

 Hab. Madagascar exclusively. 



MlCRORHYNCHUS. 



Characters. — Muzzle very short ; ears very small and hidden in 

 the fur ; tail very long ; fur woolly ; supinator ridge of humerus very 

 large ; posterior pair of upper incisors considerably larger than the 

 anterior pair ; canine scarcely exceeding first premolar in vertical 

 extent, and closely resembling it in form ; two first upper molars 

 with slight oblique ridges ; skull strongly concave between the orbits; 

 antero-posterior extent of the anterior opening of the orbit exceeding 

 the length of the muzzle in front of that opening ; a protuberance 

 just above the external auditory meatus ; an obtuse process projecting 

 from the malar over the anterior end of the zygomatic process of the 

 squamosal ; floor of orbit very little above the upper alveolar margin ; 

 no large palatine foramen behind the third molar ; palate with its 

 posterior margin not thickened; anterior palatine foramina very large; 

 mandibular symphysis nearly three times the length of the lower 

 incisors ; fossa for digastric very deep ; a vertical groove on posterior 

 part of articular surface of condyle ; inferior margin of mandible only 

 slightly concave. 



Hab. Madagascar and St. Mary's Island. 



Indris. 



Characters. — Ears exserted ; muzzle elongated ; tail short ; poste- 

 rior pair of upper incisors generally a little smaller than the anterior 

 pair ; canine considerably exceeding first premolar in vertical extent ; 

 upper molars destitute of oblique ridges ; skull not concave between 

 the orbits ; antero-posterior extent of the anterior opening of the 

 orbit less than the length of the muzzle in front of that opening ; no 

 protuberance above the external auditory meatus ; no process of the 

 malar projecting over the anterior end of the zygomatic process of 

 the squamosal ; floor of orbit considerably above the upper alveolar 

 margin ; a large palatine foramen behind the third molar ; palate 



