DESCRIPTIONS OF NEW SPECIES OF MA3IMALS. 787 



Colour. — Back and sides a coarse grizzle of black and bright ochraceous buff 

 (distinctly more yellow than Ridgway's, PI. v, fig. 10), the latter very con- 

 spicuously in excess. Under parts paler than in 3Ius stoicus, though the ele- 

 ments of the colour are essentially the same, the difference due to the more 

 extensive whitish hair tips, and faintly lighter under fur. Colour otherwise 

 as in Mus stoicus. 



Measurements. — External measurements of type : Total length, 494 mm.; 

 head and body, 266 ; tail, 228 ; hind foot, 53 ; ear from meatus, 24 ; ear from 

 crown, 21 ; width of ear, 16"4. An adult female measures : Total length, 446; 

 head and body, 237 ; tail, 209 ; hind foot, 48. 



Specimens examined. — Seven, all from the type locality. 



Remarhs. — This species is very closely allied to Mus stoicus, but is never- 

 theless easily distinguishable on comparison. It is probably the rat recorded 

 by Blanf ord as " a variety of Mus bowersi, or a closely allied form."i Mus 

 bowersi differs, however, from all of the rats known to occur on the Anda- 

 mans by its distinctly bicoloured tail. 



Mus PLEBiLis, new species. 



Ty2)e.—Advilt female (skin and skull). No 1 11841, U. S. N. M. Collected on 

 Henry Lawrence Island, Andamans, January 10, 1901, by Dr. W. L. Abbott. 

 Original number, 827. 



Characters. — A large member of the Mus rattus group. Size about as in 

 Mus pannosus of the Butang Island, but tail always considerably longer than 

 head and body. Fur thickly sprinkled with weak spines, its colour paler and 

 more yellow than in 3Ius pannosus and closely resembling that of 3Ius stoicus. 

 Skull much like that of Mus pannosus, but with larger audita! bullae, more 

 prominent supraorbital ridges, and smaller teeth. 



Fur. — The fur is like that of Mus stoicus, except that the bristles are a 

 little less stiff and the under fur is somewhat more woolly. The long terete 

 hairs on the back are less noticeable than in the larger animal. In abun- 

 dance and distribution the bristles are essentially the same in the two species. 



Colour. — Back and sides essentially as in 3Ius stoicus, except that the light 

 element of the grizzle is paler, almost exactly matching the ochraceous buff 

 of Ridgway, and a little more noticeably in excess of the dark. The fur is 

 nearly destitute of the lustrous sheen so noticeable in the larger animal. 

 Muzzle and outer surface of front legs washed with broccoli-brown. Under 

 parts and inner surface of limbs cream buff. Under fur light drab. Ears 

 and tail dull brown throughout. The colour of the under parts completely 

 encircles the mouth, but scarcely spreads upward on cheeks. Feet more 

 thickly haired than in 3Ius stoicus, cream buff heavily clouded with drab. 

 Whiskers black. A faintly indicated dark eye-ring. 



Tail. — The annulation of the tail is similar to that in Mus stoicus, except 

 that the rings and scales are more sharply defined. At middle there are 

 ten rings to the centimetre. The hairs, though not conspicuous, are longer 

 and more abundant than in the larger animal, 



^ The Fanna of British India, Mamm., 1891, p. 410. 



