OCR Text |
Show 554 MR. O. THOMAS ON THE [May 3, sandy brown, the basal halves of the hairs slate-colour. Below, the hairs are pure white, sometimes quite to their roots ; sometimes the basal halves are slate-colour; and there is every stage between the two. Tail generally nearly equal to the head and body, rarely just exceeding them, covered with hairs which are much shorter than in L. platythrix. Mammae 10, three pectoral and two inguinal pairs. Hind foot-pads six, small, circular. Ears small, oval ; laid forward they just reach to the eye. Caecum short and pouch-like. For measurements see Table, p. 556. In this species we find the link which, by way of Mus cervicolor, bridges over the space between Leggada and Mus. L. platythrix is strongly differentiated, and always shows clearly the extra cusp on the upper molar; but in many specimens of L. Buduga this cusp is not distinguishable, and these specimens are barely separable specifically from Mus cervicolor. Almost the only character to distinguish them is the different length of the ear-conch, which varies from 0*41 to 0*49 inch in M. cervicolor, and from 0*32 to 0*39 in L. Buduga. The colours and other proportions are very similar; and it seems very probable that we shall yet obtain intermediate specimens from the region where the ranges of the two species approximate-namely, in the valley of the Ganges, which seems at present to be the dividing line between the two forms. With regard to the name which, must stand for this species, it unfortunately happens that Gray's barbarous term " Booduga" antedates Elliot's name lepida by two years. W e cannot ignore the name Booduga as barbarous without also doing the same in the case of the Metad, which was called M. meltada by Gray and M. lanuginosus by Elliot in the same papers in which this species received its two names. I have therefore done what Mr. Blanford did with regard to M. mettada l-namely, correct Gray's erroneous spelling of the native name, and then use it provisionally until some final understanding is come to with regard to the use of barbarous words as specific names. Mus Beavani, Peters, of which the Museum possesses two immature individuals of the typical series, is quite undistinguishable from this species. Our specimens show distinctly the extra cusps on the upper molars ; and the proportions are quite the same. The species was described from specimens brought from Maunbhoom by Lieut. Beavan, and would appear to be the true Mus terricolor, Blyth, which is said to be " the most common field- and garden-mouse in Lower Bengal." With regard to the specific distinction of this last species, Blyth says : - " This much resembles M. lepidus, Ell., in form and colour, but the face is very much shorter, and the fur short, soft, and not spinous in the least degree." W e have seen, by many instances, how utterly valueless the character of the presence or absence of spines is ; and in this species, even when well developed, they are by no means stout or conspicuous ; and, as far as regards the shortness of the face, I have been quite unable to perceive any thing of the sort in any of our spineless 1 J. A. S. B. xlvi. p. 289 (1877). |