DESCRIPTIONS OF NEW SPECIES OF MAMMALS. 791 



Feet.—ThQ feet are in no way peculiar. Soles naked, 6-tuberculate. 



Ears.— The ears are of moderate length, about equal to distance between 

 eye and nostril. They are naked except for a fine, inconspicuous pubescence. 



Shull. — The skull is much like that of Mus rattus, except that the frontal 

 profile is more strongly concave, the audital bullae are smaller, and the region 

 between and including anterior zygomatic roots is broader and more heavily 

 built. The incisive foramina extend back nearly to level of middle of first 

 molar. 



Teeth. — The teeth are similar to those of Mus rattus, but very much larger. 



Measurements. — External measurements of type : Total length, 342 mm. ; 

 head and body, 160 ; tail, 182 ; hind foot, 36 ; ear from meatus, 18 ; ear from 

 crown, 14 ; width of ear, 13. Average of seven adults from the type locality : 

 Total length, 353 (342— 372) ; head and body, 175 (160—195); tail 181 

 (173—190) ; hind foot, 39-7 (39— 41'6) ; hind foot without claws, 37-3 (36—39). 



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



Remarks. — In the appendix to Mouat's Adventures and Researches among 

 the Andaman Islanders, Blyth remarks that — 



lately the Rev. C. S. P. Parish, the able botanist and chaplain of Moulmein, observed on 

 Barren Island the half -devoured remains of some rat, which it is not likely had been carried 

 by a bird of prey from the nearest land, 36 miles distant. As the carcase was much mutilated, 

 Mr. I'arish did not think it worth while to preserve it in spirits, though had he done so, 

 the identification of the species, with the peculiar spiny-coated Mus andamanensis, would 

 probably have been easy. 



This is the only published allusion to the Barren Island rat that I have seen. 



Dr. Abbott found the animal excessively abundant in favourable localities 

 among the patches of grass and scrubby jungle with which the volcanic ash and 

 scoria of Barren Island are covered. He noted nothing peculiar in its habits, 

 Mus BDRRUS, new species. 



Type.— Adult female (skin and skull). No. 111811, U. S. N. M. Collected on 

 Trinkut Island, Nicobars, February 5, 1901, by Dr. W, L. Abbott. Original 

 number, 881. 



Characters. — Size and general appearance much as in Mus pulUventer, but 

 tail shorter, back less distinctly grizzled, and belly light buff. Fur spineless. 

 Mammae 10. Skull much like that of Mus norvegicus. 



Fur.— The fur is like that of Mus atratus, that is, the spines are so reduced 

 in diameter that on casual examination they do not appear different from the 

 surrounding hairs. They are, however, slightly larger than in Mus atratus. 



Colour. — Back and sides a fine grizzle of black and russet, the colours nearly 

 as in Mus pulUventer, but grizzle less distinct. The two elements are in about 

 equal parts on back, but on sides the russet is considerably in excess of the 

 black, and at the same time slightly obscured by the drab gray of the under 

 fur. Under parts and inner side of legs cream-buff to base of hairs. Crown 

 and forehead like back, but a little tinged with gray ; cheeks washed with 

 drab. Feet scantily clothed with whitish and brownish haira. Ears and 

 tail uniform dark brown. 

 20 



