MAMMALIA — RODENTIA. 
55 
declared, from an examination of a skin, that the nipples, in fact, though 
not exactly upon the back, yet lay inches above the mesial line of 
the sides, and that the animal was nothing else than the well known 
Myopotamus coypus. He promised further information on the receipt 
of two living specimens, which had been promised him (p. 226, also 
given in the Isis, 1842, p. 356). Sundevall gave a confirmation of this 
fact, in the Arsber. om nyare Zool. Arbet. p. 538. The question was 
now not one of a fable, but only of correct interpretation. Farther 
evidence of this appeared. Dr. RiipiDell informed me, about the 11th 
February, that he had found, in two females of the Myopotamus from 
Chili, the nipples, four pair in number, just as Fahrseus had described 
them ; and he observed, that Christie, in the Proceed. Zool. Soc, 1835, 
p. 182, had previously mentioned, that in this animal the nipples were 
situated “ uncommonly high on the sides.” In a third specimen in 
Frankfort, probably a male, excrescences were not found on the sides. 
At the same time. Dr. Schinz informed me, that he had observed the 
same position of the nipples, not merely in the Myopotamus, but also in 
the Lagostomus. About 3d March, I received from Erichson the infor- 
mation, that he had convinced himself, from the examination of a skin 
from Chili, of the correctness of the earlier assertions. He laid before 
me, at the same date, a notice from Sundevall, who had kept for a while, 
in Stockholm, a live adult male of Myopotamits, and on which, after its 
death in the previous May, no trace of excrescences were found. In 
addition, I have to remark, that I have found, very distinctly, these 
excrescences in a specimen in the collection here. It is therefore proved, 
that in Myopotamus, merely in the female however, nipple-like organs 
are found high on the sides, but their function has not yet been pointed 
out. That they represent nipples is probable, from their absence in the 
male ; but in order to be certain of it, either their connection with the 
mammary glands, or at least the fact of suction, by means of these 
organs, must be shown. One circumstance struck me on the examina- 
tion of the specimen here, a very large old individual, that these excres- 
censes were quite concealed beneath the under fur, and surrounded by it, 
whilst in others the nipples are situated on the naked skin. It is a very 
interesting fact, that a similar position of these organs has been found 
by Dr Schinz in Lagostomus, but we have both sought in vain for them 
in the Chinchilla. * 
Dr. Riippell has drawn my attention to a circumstance which deserves 
farther observation. In both his specimens from Chili, the fur is dark 
brown, grisled with bright brown ; the top of the nose is also dark brown, 
but with a whiter spot at the point, and the mouth is edged with white. 
* Neither could I find them iu the stuffed skins of Lagostomus, especially 
in the Hare-vaxcQ, of this collection. — Editor of Arch. 
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