SPERMOPHILUS HARRISII.--AUD. and BACH.
                          [Ammospermophilus harrisii]

                   HARRIS'S SPERMOPHILE, or MARMOT SQUIRREL.
                          [Harris's Antelope Squirrel]

                              PLATE CLIV.--FIG. 1.


     S. Magnitudine Tamiae Lysteri; strigis duobus albis dorsalibus ab humeris
ad femora; fronte rufo-canescente, colle et ventre cinereis-albis, dorso
fulvo-cinereo; cauda disticha.


                                  CHARACTERS.

     Size of Tamias Lysteri; a narrow white stripe on each side of the back,
from the shoulder to the thighs; forehead reddish-grey; neck ashy-white running
into yellowish iron-grey on the back; under surface ashy white; tail distichous.


                                  DESCRIPTION.

     Head small and delicate; neck, rather long; body slender; legs rather long,
a few long hairs growing out and fringing the hind parts of the fore legs; the
cheek pouches appear rather small in the dried specimen; ears thinly clothed on
both surfaces with short adpressed hairs; short, somewhat triangular, and rather
acute at the tips; tail of moderate length, depressed at base, with the hairs
growing from the side, giving it a decidedly distichous appearance; the teeth
resemble those of T. Lysteri are rather small, and the lower incisors are
slightly curved.
     Whiskers not numerous, reaching the ear; hairs on the back very short,
somewhat coarse, but lying very smoothly, giving the animal a glossy appearance;
on the under surface they are coarse and rigid.  There are five toes on each
foot; on the fore-feet a small tubercle in place of a thumb, with a blunt nail;
second nail from the thumb longest, as in the rest of the spermophili; on the
hind feet the middle toes are longest, the two on each side being of nearly
equal length, the outer considerably shorter, and the inner shortest; claws
slightly compressed, and a little curved; feet clothed with short hairs, but
which do not conceal the nails; the eyes are of moderate size, and are placed
midway between the point of the nose and the root of the ear; soles of feet
tuberculated and naked, except a few hairs between the toes.


                                    COLOUR.

     Incisors dingy yellow; whiskers and nails black; back and sides minutely
speckled with white, on a yellowish-brown ground; the hairs are dark-brown at
the roots, then white, then black, and the tips brownish-white, with a tinge of
yellow; on the nose and forehead, the speckled appearance of the back is
superseded by a rufous tint; between the ears, on the neck, and a little
downwards, towards the legs, greyish-white is the prevailing color; a narrow
white stripe, rising from behind the shoulder, and running along the side of the
back to the middle of the hips, there loses itself in the general colour of the
body; around the eye, throat, chin, inner surface of legs, and whole under
surface of body, whitish, with a few black hairs interspersed; a tinge of
brownish-red on the outer surface of the fore legs is more strongly red on the
thighs; feet and outer surface of legs yellowish white.
     The hairs of the tail are whitish at the roots, twice annulated with black,
and tipped with white.
     There is a line of whitish yellow on the flanks, separating the colour of
the back and sides from the under surface distinctly, and extending along
beneath the reddish brown tint on the thighs, where it becomes a deeper yellow.


                                  DIMENSIONS.

                                                            Inches.

     Length of head and body.  .  .  .  .  .  .  .  .  .  .  5 3/4
     Length of tail (vertebrae).  .  .  .  .  .  .  .  .  .  3 1/4
     Length of tail to end of hair.  .  .  .  .  .  .  .  .  4 1/2
     From tarsus to end of longest claw .  .  .  .  .  .  .  1 1/2
     Length of fore leg from the shoulder  .  .  .  .  .  .  2
     Length of hind leg from the thighs .  .  .  .  .  .  .  2 1/2
     Breadth of tail, when distichously arranged .  .  .  .  1 3/4
     Height of ear (posteriorly)  .  .  .  .  .  .  .  .  .    1/8
     Longest claw on the fore foot.  .  .  .  .  .  .  .  .    1/8


                                    HABITS.

     There is nothing to be said by us about the habits of this species, as it
has not been observed, so far as we know, since our specimen was procured, and
we have not even a knowledge of the precise locality in which it was obtained by
Mr. J. K. TOWNSEND, who gave the specimen to our esteemed friend, EDWARD HARRIS,
Esq., from whom we received it some time since, and with whose name we have
honoured this pretty little animal.


                           GEOGRAPHICAL DISTRIBUTION.

     Probably west of the Rocky Mountains, on the route followed by Messrs.
NUTTALL and TOWNSEND, in their journey to Oregon overland.


                                GENERAL REMARKS.

     This species bears a very slight resemblance to Spermophilus lateralis of
SAY, but differs so widely from it that it is unnecessary to institute a close
comparison.  It is a smaller animal, the head and ears being diminutive compared
with the latter; it has a single stripe of white on the sides of the back,
whilst in Lateralis a broad white stripe is margined on each side by a stripe of
black, giving it the appearance of having four black stripes on the back, while
S. Harrisii has no black about the back or sides at all.

                           ARVICOLA EDAX.--LE CONTE.
                            [Microtus californicus]

                            CALIFORNIA MEADOW MOUSE.
                               [California Vole]

                              PLATE CLIV.--FIG. 2.


     A. Brevis et robustus, supra spadiceo et nigro permixtus.  Auribus extra
pilos extantibus.  Cauda mediocri, supra nigra, subtus cinerea.


                                  CHARACTERS.

     Body short and thick; above, brown mixed with black; ears not concealed by
the hair; tail moderate length, black above, beneath grey.


                                   SYNONYME.

     ARVICOLA EDAX.--Le Conte, Proc. Acad. Nat. Sci., Phil., Oct. 1853, p. 405.


                                  DESCRIPTION.

     Head short and blunt; ears round, not entirely concealed under the fur,
hairy within and without, antitragus large and semicircular; feet covered with
short, shining grey hair; thumb tubercle, with a short, very blunt nail; tail of
moderate length, hairy above.


                                    COLOUR.

     Hair plumbeous black above and on the sides, tipped with shining brown
mixed with black; beneath tipped with grey; feet grey; tail dusky above, grey
beneath, with a slight brownish tinge.


                                  DIMENSIONS.

                                                        Inches.

     Length (including the tail)  .  .  .  .  .  .  .  .  5.5
     Length of head.  .  .  .  .  .  .  .  .  .  .  .  .  1.4
     Length of ears.  .  .  .  .  .  .  .  .  .  .  .  .   .5
     Length of fore leg  .  .  .  .  .  .  .  .  .  .  .  1.3
     Length of hind leg  .  .  .  .  .  .  .  .  .  .  .  1.5
     Length of tail.  .  .  .  .  .  .  .  .  .  .  .  .  1.5


                                    HABITS.

     This new Arvicola from California has doubtless the habits of the genus to
which it belongs.  Our friend Major LE CONTE does not, however, say anything in
relation to its peculiarities, and as all our information of the existence even
of the animal is derived from that gentleman, we have nothing to say further.
We present our thanks to Major LE CONTE for the loan of the skin from which our
figure was made.


                           GEOGRAPHICAL DISTRIBUTION.

     California is named as the habitat of this Meadow Mouse; but we are not
informed whether it is widely diffused there, or is confined to certain
localities.


                                GENERAL REMARKS.

     The description and dimensions of the California Meadow Mouse above given
are quoted with slight alterations from Major LE CONTE's paper cited above.