25C PROF, ALLMAN ON POTAMOGALE VELOX. [Mar. \4, 



extent of the orbit about equal to the length of the muzzle in front 

 of that opening ; a very slight protuberance above the external au- 

 ditory meatus ; no process of the malar projecting above the anterior 

 end of the zygomatic process of the squamosal ; floor of orbit not 

 much above the upper alveolar margin ; all posterior palatine fora- 

 mina moderate ; mandibular symphysis not much less than three 

 times the length of the lower incisors ; fossa for digastric very deep ; 

 posterior part of articular surface of condyle very much flattened ; 

 angle much bent downwards, making inferior margin of mandible 

 decidedly concave. 

 Hab. Madagascar. 



Indris laniger. 



Characters. — Ears very small and hidden in the fur ; muzzle very 

 short indeed ; fur woolly : supinator ridge of humerus very large ; 

 posterior pair of upper incisors considerably larger than the anterior 

 pair ; upper canine (sometimes at least) scarcely exceeding first pre- 

 molar in vertical extent ; 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 marked pro- 

 tuberance 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 last 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 indeed ; 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. 



EXPLANATION OF PLATE XVIII. 



Fig. 1. Upper surface of the skull of Indris diachma. 



2. Under surface of the same. 



3. Side view of the same. 



4. Side view of the outside of tlie mandible of /. diadcma. 



5. Grinding-surface of the right dental series of the same. 



(All the figures are of the natural size.) 



2. Supplementary Note on Potamogale velox. 

 By Prof. Allman, F.R.S., Corr. Mcmb. Zool. Soc. 



Mr. St. George Mivart having recently expressed a wish to inspect 

 the skull of the Potamogale velox, described by me at a former 

 Meeting of the Society*, I had much pleasure in placing it at his 

 disposal. Shortly afterwards I received from him a note reminding 

 me of the discrepancy between the number of teeth in the dental 

 * Trans. Zool. Soc. vi. pt. 1, June 18G3. 



