curved, and much compressed. Their edges are in contact beneath at their insertions into
the ends of the toes, and separate a little towards their points, being very similar in form to
the claws of the spermophiles, but not so strong in proportion to the size of the animal. The
middle claw is the longest; those belonging to the thumb and outer toe are much shorter and
more conical than the rest, but they are in other respects similar, the thumb-claw differing in
that respect from the obtuse, rounded flat thumb-claw of a spermophile.
The hind-feet are covered above with whitish hairs. The soles are naked and narrow, and
the toes short. The first and fifth toe are so much smaller and further back than the others,
that, at first sight, there appear to be only three hind-toes. Of these three the middle one
is longer than the one on each side of i t ; and of the other two, the first toe is a little further
back, but somewhat larger than the outer or fifth one. The hind nails are short, conical,
obtuse, and more or less excavated underneath. The nail of the fourth toe is more spoonshaped
than the others.
Dimeksioxs.
Inches. Lines Inches. Lines.
Length of the head and body . . . 11 0, Length of middle hind-toe , 0 4
„ „ EeacT . . _ . 3~ 0 middle hind-claw , 0 2
Breadth of the head behind the eyes, when , , upper indsors (the exposed portion} 0 6
. the pouches are distended 3 6 , , lower incisors ditto . . 0 a
Length of the tail- . . . . 2 6 „ from the orbit to the tip of the nose 1 2
- ,, palm, middle fore-toe and claw 1 0 „ of the orbit, about . 0 3
,,. middle fore-toe .. 0 3 „ from the orbit to the auditory opening 0 6
. ,, middle fore-daw •------. 0 4* Height of the b a d ? , about . 4 Q
, , sole, middle hind-toe and daw 1 6 Length of the fur on the back . . . 0 6
M. Rafinesque has not detailed the characters of his diplostoma fusca from the
Missouri sufficiently to enable us to judge how far it differs from the camas-rat;
but the furrows on the upper and lower incisors of his species, and no mention
being made of the white fur about the mouth, lead me to consider it as distinct.
The want of a tail, and the smaller number of toes on his specimen, may have
been owing to an injury the skin had sustained, as he had not an opportunity of
examining the recent animal.
Mr, Schoolcraft gives a description of a “ gopher” that he procured at the
Falls of St. Anthony, on the Mississippi, which I shall transcribe, as it contains
the fullest account of the habits of these animals which I have met with. “ It is
about ten inches long from the nose to the tail, with a body shaped very much
like that of a large wharf-rat, which it also resembles in the colour of its hair and
the length and nudity of its tail. Its legs are short, and each foot is furnished
with five long and sharp claws. It has two large fore-teeth in each jaw, resembling
those of the squirrel, but its most remarkable character is a pouch on each side of
the jaw, formed by a duplicature of the skin of the cheek. These project inwardly,
where they are accommodated by an unusual width and flattening out of the head.
As the animal lives wholly under ground like a mole, these pouches serve the
purpose of bags for carrying the earth out of their holes. They are filled with the
fore-claws, and emptied at the mouth of the hole by a power which the animal
possesses of ejecting the pouches from each cheek in the manner that a cap or
stocking is turned. In this way it works its path under ground, and ploughs up the
prairies in many places in such a manner, that the white hunters of the Missouri and
Arkansas frequently avail themselves of the labours of the gopher by planting
corn upon the prairies which have been thus mellowed. It lives entirely upon
the roots of plants, eating all with indiscriminate voracity, and has been found
particularly destructive to beets, carrots, and other tap rooted plants in the military
gardens at St. Peter’s*.*’
Mr. Schoolcraft’s account of the manners of the Mississippi gauffre, and the
mode in which it uses its cheek-pouches, is evidently the testimony of an eyewitness,
and may be compared with Mr. Douglas’s equally clear and precise
description of the habits of the Columbia sand-rat. A minute examination of the
specimens in my possession induces me to place implicit reliance on both these
accounts. The skin of the geomys Douglasii, even when thoroughly soaked, cannot
be made to fold in, so as to produce the hood-like cheek-pouch of a gauffre, neither
can the pouch of the diplostoma bulbivorum be everted, so as to become pendulous.
Its bottom alone can be turned out, by which it is emptied of its contents
in the manner mentioned by Mr. Schoolcraft; but the lining of the exterior parietes
of the pouch is firmly united to the external skin, and is incapable of being everted.
The incisors in form and position, the form of the mouth, the ears, eyes, extremities,
and tail of the sand-rats, bear, however, a very close resemblance to those of the
gauffres, and they cannot be finally established as separate genera, until their
dentition has been compared. The Camas-rats are very common on the plains of
the Multnomah River, and may, as Mr. Douglas informs me, be easily snared in
the summer.
* Schoolcraft, Journ., p. 365.