102 MR. 0, THOMAS ON RODENTS FROM PERU.  _[Jan. 17, 
quil Rat as Nectomys apicalis, g. and sp. n., the genus being founded 
on the presence of short webs to the toes, including H. squamipes, 
Bts., from which V. apicalis was separated on account of its only 
having 5 instead of 6 hind-foot pads. I do not, however, think 
that the presence of webs to the feet is a character of generic im- 
portance, and should prefer to regard Nectomys as only a subgenus 
of Holochilus. The specific distinction of H. apicalis is, no doubt, 
quite correct, as all the specimens in the present collection agree in 
having only 5 hind-foot pads. None of them have, however, the white 
tip to the tail described by Prof. Peters ; but this is no doubt a point 
in which there may be considerable variation. The incisors of H. 
apicalis were originally said to be snow-white ; but the present speci- 
mens do not agree with this, their incisors being pale yellow; but 
they are certainly very much lighter-coloured than in H. squamipes, 
where they are a rich orange. Notwithstanding these differences, I 
do not think there can be any doubt that these specimens belong to 
Prof. Peters’s species, as they agree perfectly in size, locality, and 
the very important character of the number of the foot-pads. 
There is in the British Museum another specimen of this species, 
collected by Mr. J. K. Salmon at Concordia, Medellin, U. S. of 
Colombia. 
(a) “ Appeared to be aquatic, although caught in a cultivated 
field.”’ 
(2) “ Killed in an arm of the river just as it was seizing a branch 
of a Guava-tree, which touched the surface of the water. It had in 
its stomach an aromatic mass composed of fruity substance. It swims 
perfectly, only coming out late in the evening, and is probably the 
animal which gnaws the fish taken in the Indians’ nets. It is not 
possible to catch it in a rat-trap.” 
4. Hesprromys (Catomys) taticeps, Lund, Blik p. Bras. 
Dyrev. iii. p. 279 (1841). 
a-c. Huambo, 3700’, April and May 1880. 
Head and Forearm Ear-conch, Muzzle 
body. Tail. Hind foot. andhand. length. to ear. 
aS 0 6°3 1°35 1:44 ‘70 1°14 
To this species I refer three specimens, of which, however, only 
one is adult. The tarsus seems to be somewhat longer than in the 
original specimens ; but otherwise it agrees very fairly with a spe- 
cimen of H. laticeps in the Museum collection from the original 
locality, Bahia. This Bahian specimen, however, is only askin; and 
it is therefore quite possible that spirit-specimens would show such 
differences from the Peruvian one, that, combined with the greater 
length of the tarsus and the difference in locality, a new species 
would have to be formed for the latter. 
The following is a description of the adult individual, a male:— 
Fur rather short and close, compared with that of H. albigularis 
or leucodactylus. General colour above dull brown, very finely 
