OCR Text |
Show 166 MR. ST. GEORGE MIVART ON MICRORHYNCHUS. [Mar. 13, fifth digit; pollex short and placed far back ; hallux very long covered with hair ; tail long, or very short and rudimentary ; internal condyle of the humerus perforated; carpus destitute of an os intermedium ; 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 transversely extended ; articular surface prolonged somewhat down the back of ascending ramus ; digastric fossa deep. Hab. Madagascar exclusively. MICRORHYNCHUS. 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 iucisors ; 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; posterior 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 |