28S Proceedings of the Asiatic Society. [No. 3. 



white mesial Hue below. In other respects like Sc. macrourus of the 

 southern parts of India and Ceylon. However the latter may vary, the 

 fore-limbs from the elbow are invariably white, and also a corresponding 

 portion of the hind-limbs ; the crown is blackish, with white muzzle and 

 white occipital patch ; and there is a great admixture of white on the 

 tail, either merely tipping the hairs more or less, or rarely almost the 

 whole tail is white or yellowish-white. There is commonly also much 

 white grizzling the sides of the body. From the dark limbs more especi- 

 ally, I take that now described to be of a particular race, equivalent to 

 many others that are named ; but the habitat remains to be ascertained. 



Fam. Myoxidce, Waterhouse. 



Platacanthomys, nobis, n. g. A most remarkable new genus, having 

 essentially the dentition, form of skull, and also the hirsute tail of a Dor- 

 mouse (Myoxus, Graphiurus), but the upper-parts are densely covered 

 with sharp flat spines, mixed with an exceedingly delicate, thin, and some- 

 what frizzled under-coat ; with spines also on the lower-parts, but these 

 much smaller and finer (more resembling those on the upper-parts of Mus 

 platythrix), and the soft under-coat there predominating ; with no 

 spines on the head and throat, limbs, and hind-portion of the abdomen, 

 but the hair on the forehead and occiput full and tufty, each hair being 

 flattened and the series passing gradually backward into spines. The 

 skull could not be taken out without injury to our only specimen, but on 

 the skin being relaxed and reversed, all doubt was completely removed 

 respecting the affinity of this curious animal. The grinders, however, 

 are only three in number, above and below, of equal size, excepting that 

 the last above is one-third smaller than the rest ; each is surrounded with 

 enamel, with three or four transverse folds of the same, comparable to 

 those of the grinders of an Asiatic Elephant, only simple and contiguous 

 or very nearly so. The descending angle of the lower jaw quite resembles 

 that of Sciueus ; but the coronoid process is obtuse. From what little 

 remains of the skull, it would seem to resemble very nearly that of Gka- 

 phiurus (vide Waterhouse in Mag. Nat. Hist., n. s., III. 1839, p. 185), 

 but the nasal bones do not contract posteriorly, and the inter-orbital space 

 is also less contracted. Ant-orbital foramen as in Myoxus, but the 

 maxillary process which forms its outer wall is less than half as broad as in 

 Myoxus, or more as in Graphiurus. Eodential tusks quite similar to 

 those of Myoxus glis. Comparing the feet with those of the latter ani- 

 mal, the structure is seen to resemble, except that in the new genus, the 

 hallux is less developed and is nailless. The tail, too, is less hirsute on 

 its basal third, the hairs becoming gradually longer from the base to the 

 middle and being of equal length for the remainder ; they are thinner 



