PtEROMYS LEPIDUS. 



Ord. IV"^ Rongeurs, Cuvier. V^ Division. 



Ord. IV. Glires, Linn. Syst. 



Ord. IV. Prensiculantia, IlUger. Fam. 9, "AgiJia. 



PTEROMYS, Cuv. Geoffr. Illig. 

 SciURUS, Linn. Briss. Schreh. Pallas, S^c. 

 Petauristus, G. Fischer, Zoognosia, Vol. III. jo. 498. 



Char. Gen, — Dentium formula ; Primores |-, Molares ^. Primores superiores 



pagina antica laevigati, inferiores compressi. Pro Laniariis diastema. Molares 



abrupti obducti tritores, supra antico accessorio. 

 Rostrum obtusiusculum. Labrum fissutn. Saeculi huccales nuUi. Auriculce rotun- 



datas. Cauda elongata. ' Mammee apertge, pectorales et ventrales. 

 Pedes dermopteri : patagium lumbare s^pius in angulum anteriorem dilatatum osse 



fultum, interdum patagium collare adest. Antipedes digitis quatuor et verruca 



hallucari, scelides pentadactylas. Illiger, 



Pteromys nigricante-fuscus, subtus albus, capite dorsoque medio canescentibus, 

 Cauda corpore longiore oblonga plana disticha, auriculis oblongis simplicibus 

 nudis, vibrissis aggregatis longissimis. 



In the description of the Pteromys genibarbis, contained in the Fourth Number 

 of these Researches, the pecuharities of the Sciurus sagitta, as they are given in the 

 12th Edition of the Systema Naturae from Nordgren, are concisely enumerated. A 

 ferruginous tint mixed with the brown of the upper parts, a membrane extending 

 from the head to the anterior extremities, and a size not exceeding a palm in length, 

 distinguish that animal both from the Pteromys genibarbis and from the Pteromys 

 lepidus, which is now to be considered. 



The characters which principally distinguish the Pteromys genibarbis from our 

 animal, are a large series of bristles, which covers the cheeks in a radiated manner ; a 



