168 GLIRES. 
specimen from Guatemala is nearly as dark as “ melanolewcus,” has the proportionally 
short tail of “dérroratus,” and is strictly intermediate in the hairiness of its ears. The 
tail of the type of H. longicaudatus has been skinned and obviously much stretched ; 
but as this is the only one of Gray’s names which is not absolutely misleading, it 
should now be retained. 
The range of this species extends from Southern Mexico to Colombia, whence it was 
sent by Salmon to the British Museum, and to Venezuela, which is the true habitat of 
“ H. melanoleucus.” Dr. v. Frantzius does not appear to have met with it in Costa Rica ; 
but there is an example from that country in the British Museum. Messrs. Godman and 
Salvin tell me that it is a scarce animal in Guatemala. ‘There is a specimen in the 
Museum of the capital of that republic with the cheek-pouches turned inside out, but 
with no record of where it was captured; and the only examples they obtained were 
caught by Indians near Duefias: one of these last is the subject of our figure. 
[OCTODONTIDZ.. | 
In my general observations on the present order* I remarked that the important 
Neotropical family of Octodontide was represented in the Central-American fauna by 
a single form, Myopotamus. I much regret to find that I have been led into a mis- 
statement. The source of error lies in the following passage in Dr. v. Frantzius’s often- 
quoted paper :—‘ According to oral information received from J. Carmiol, a botanist 
and zoological dealer resident in Costa Rica, an animal is found on the San Carlo River, 
which, from his description, I consider must be either Hydrocherus capybara or Myo- 
potamus coypus. From correspondence with Professor Baird it appears that the latter 
has also been found in Guatemala by Salvin; and it is therefore very probable that the 
animal seen by Carmiol is the Coypu, in which case it is doubtless to be found in other 
parts of Central America”. It was on the last sentence that I relied ; for Sefior Carmiol’s 
“description” must have been of the vaguest sort; but on applying (somewhat late in 
the day perhaps) to Mr. Salvin for further particulars, I find that either Professor Baird 
or Dr. v. Frantzius must have made a mistake, and that he never saw or heard of the 
Coypu in Central America. 
Besides Myopotamus coypus, Dr. v. Frantzius has claimed Octodon degus (Molina) as 
a native of Costa Rica, on the strength of a specimen which he received from Turialba 
in 1859. Unfortunately the skin was lost on its way to Kurope, so that all the material 
for identification left was the following short description which the Doctor had drawn 
up:—‘The pencilled tail and the rounded nail of the thumb of the fore foot left no 
doubt that it was a species of Octodon. The colour of.the soft fur was grey-brown 
above, lighter below; the length of the body was 4% inches, of the tail the same; the 
whiskers had a length of 24 inches, and stood up above the occiput.” On examining 
* Supra, p. 120. . f Arch. f. Naturg. xxxv. 1, p. 275. 
