1861.] OP GUATEMALAN MAMMALS. 285 



Obs. It is probable that this subgenus will have to be elevated to 

 the rank of a genus, as it possesses more strongly marked characters 

 than any group yet indicated, if we except Oxymicterus, which must 

 be regarded as a genus. 



26. Hesperomys (Myoxomys) salvinii, n. sp. (PI, XXXI.) 



In general form this species bears great resemblance to the Myoxiis 

 nitela of Europe, and it is of nearly the same size. The head is 

 short and rather broad ; but the face, although broad also, has the 

 muzzle somewhat pointed. The muffle is of small size, quite naked, 

 and cleft vertically ; beneath the nostrils, which are crescent-shaped, 

 are two descending points. The cleft in the muffle is continued 

 through the upper lip to the teeth. The whiskers are long, almost 

 twice the length of the head, and black. The ears are rather large 

 for the size of the animal, broadly oval, and sparingly clothed with 

 short inconspicuous hairs inside and out. 



The fore feet are rather broad, short, and have the middle toes not 

 exceeding the others in length by more than a hne ; the thumb is 

 rudimentary, and its nail short and truncated. The tubercles of the 

 palms are large, roundish, and prominent ; they are five in number — 

 one at the root of each of the middle toes, one at the root of each 

 of the outer toes, another constituting the inner surface of the rudi- 

 mentary thumb, and the remaining one near the outside of the palm 

 directly opposite to the thumb. The toes themselves have their inner 

 surfaces veiy thick and fleshy, especially at their ends ; and they have 

 transverse depressions, which are less distinctly marked and further 

 apart than in most species of Hesperomys. The hind feet are remark- 

 ably short and broad, and have the toes so nearly of a length that 

 the middle ones are scarcely half a line longer than those on either 

 side of them ; the inner toe is scarcely half the length of the one next 

 to it. When seen from beneath, the ends of all the toes are thick 

 and fleshy, like so many fingers ; and, indeed, the foot, when seen 

 from this position and the toes partially closed, has more the ap- 

 pearance of the foot of a cat than of one of the Muridcs. This 

 arises not merely from the form of the fingers themselves, but also 

 from the size and form of the tubercles on the sole of the foot. These 

 are six in number, rounded and prominent. The three anterior ones 

 are arranged like those of the fore feet, the fourth is at the root of 

 the inner or small toe, the fifth behind the tubercle of the outer toe, 

 and near the outside of the sole, and the sixth behind that of the 

 inner toe, and cousequently posteriorly to all the others. The clawg 

 of all the feet are short and white. The sole of the hind foot has 

 its posterior third well clothed with hairs, but the tubercular 

 part (as well as the under surface of the toes) is perfectly naked. 

 The tail is about the length of the head and body, and tapers only 

 iu a trifling degree; it is annulated with small 'scales, which are 

 nearly concealed by longish black hairs, which become thicker towards 

 and at the end, where they form a kind of pencil. 



The general colour is like that oi Neotoma fevruginea, viz. brightish 

 rufous on all the upper parts, with a mixture of blackish hairs along 



