10 

 O 



those of N. floridana^ in rich rusty-red on the sides and partly 

 dusky metatarsus. 



To the foregoing list I append the description of an apparently 

 new species of this group: — 



6. Hesperomys (Vesperimus) melanophrys, Coues, n. s. 



Syn. ? ? Hesperonti/s mexicanus, De Saiiss., R. M. Z. 1860, p. 00 (p. 20 of 

 reprint), pi. ix. figs. 1, la. 



Descr. from No. 10,183, Mus. Smiths., Sta. Efigenia, SumichTast. 

 General aspect of a species of the leucojjus group. Large; nose 

 to eye 0.62 (inches and hundredths), to ear 1.12, to occiput 1.40, 

 to tail 4.15 ; tail 5.00 ; fore foot 0.42 ; hind foot 1.04 ; ear 0.18 above 

 notch. Tail a little longer than head and bod}-, slender, scant-haired- 

 Absolute and relative proportions of feet and digits as in V. leu- 

 copus; soles hair}' on posterior third. Ears large, leafy, ap- 

 parently naked, really closely pilous. Whiskers reaching to or 

 bej'ond the shoulder. Skull strictly as in V. leucopun (palate 

 ending opposite last molars, not far behind it as in J/us, Oi'yzomys^ 

 etc.), but not quite so thin and papery, and developing a slight 

 bead on the orbital border, as in the stouter mice generally. 

 Color above giving the general impression of a gray mouse, rather 

 than a red mouse with darker dorsal area as in leucopus and 

 azfecus. It is gray, brightened with fulvous, slightly darker 

 along the back, more decidedly fulvous laterally, and everywhere 

 with a peculiar slight glaucous or hoary shade. Head noticeably 

 purer gra}'; eye encircled tvith a black ring in marked contrast, 

 the edges of the lids, and a little anteocular spot, being jet black. 

 (This suggests the specific name; I have seen nothing like it else- 

 where.) Color below, pure white, the plumbeous roots of the 

 hairs, however, giving a slight gra3'ish cast. Line of demarcation 

 of this white with the color of the upper parts everywhere abrupt. 

 Outside of fore leg colored to the A^ery wrist, but back of the hand 

 white. Hind leg also colored to and a little beyond the ankle, 

 forming a definite dark spot on the base of the metatarsus, the 

 remaining five-sixths of the foot being pure white. Tail above, 

 like the back; below, gray — not white; and the line of demarca- 

 tion, though evident, not sharp. No yellowish or fulvous tinge 

 anywhere on the under parts {^'"mexicanus''^ of De Saussure is said 

 to be yellowish on the chin and breast). Skull 1.20 long hx 0.64 

 broad. 



