1882. ] MR. O. THOMAS ON RODENTS FROM PERU. 109 
Fur extremely long and soft, only exceeded in this respect by 
H. longipilis, Waterh. General colour above grizzled ashy grey, 
the hairs being, as usual, slate-coloured for five sixths of their length, 
and the tips white, with numerous wholly black longer hairs inter- 
mixed. This colour lightens gradually into the greyish white of the 
belly, where the basal two thirds only of the hairs are slate-colour. 
Anterior edge of the outer side of the ears thickly clothed with long 
and soft dark brown hairs, as also is the posterior half of the in- 
ternal surface, though there the hairs are much shorter. Tail un- 
usually thick, tapering to a point, brown above and white beneath, 
the two colours not sharply separated, closely covered with short 
shining hairs from root to tip, nearly hiding the scales; there is, 
however, no terminal penci! of longer hairs. Upper surfaces of 
feet covered with pure white shining hairs, much longer than usual, 
those at the tips of the toes quite hiding the claws. Foot-pads 
large and prominent. Fifth hind toes reaching to the middle of the 
second phalanx of the fourth toes. Mammz 6, one pectoral and two 
inguinal pairs. Ears without a projection on their anterior edge. 
Incisors rich orange; upper margins of orbits without any trace 
of ridges. 
This very peculiar-looking Rat may be readily distinguished from 
all its allies by its very long soft fur, its thick and tapering tail, and 
by the unusual hairiness of both ears, feet, and tail, the result, no 
doubt, of the extreme height at which it was obtained. 
I can find no species with which it could by any means be con- 
fused. H. galapagoensis, Waterh., bears a superficial resemblance 
to it, but differs by several of the more important characters, having 
8 mamma, naked extremities, and a well-marked projection on the 
anterior edge of the ear. 
The next species seems to be really the most nearly related to it, 
though its general appearance is quite different. 
As there is only a single specimen of this species in the collection, 
Prof. Taczanowski has been unable to let the British Museum have 
an example. I have therefore had the species figured (Plate IV.), 
so as to make it more readily recognizable by those unable to exa- 
mine the type in the Warsaw Museum. 
11, HespEromys (RHIPIDOMYS) TACZANOWSKII, Sp. 0. 
a, 6. Tambillo, 5800’, February 1878. 
(!) ¢ (imm.). Cutervo, 9200!, Feb. or March 1879. 
Head and Forearm LEar-conch, Muzzle 
body. Tail. Hind foot. and hand. length. to ear, 
ie Oar wie 3°55 5'°3 88 1-11 "45 97 
6.dé(imm.) 3:0 4:9 "87 1:04 50 87 
Fur of medium length, soft and woolly ; general colour above greyish 
yellow, the hairs being tipped with rufous yellow, with very few 
longer darker hairs. Head greyer and less yellow. Belly, as usual, 
greyish white, the separation of the upper and under colours quite 
gradual. Ears thinly clothed with brown hairs. ‘Tail pale brown 
