MUS RATTUS.--LINN.
                                [Rattus rattus]

                                   BLACK RAT.


                PLATE XXIII.--OLD AND YOUNG, OF VARIOUS COLOURS.



     M. cauda corpore longiore; pedibus anterioribus ungue pro pollice
instructis; corpore atro, subtus cinereo.

                                 CHARACTERS.

     Tail, longer than the body; fore-feet, with a claw in place of a thumb,
bluish-black above, dark ash-coloured beneath.


                                   SYNONYMES.

     MUS RATTUS, Linn., 12th ed., p. 83.
     MUS RATTUS, Schreber, Saugethiere, p. 647.
     MUS RATTUS, Desmar., in Nouv.  Dict., 29, p. 48.
     RAT, Buffon, Hist. Nat., vol. vii., p. 278, t. 36.
     RAT ORDINAIRE, Cuv., Regne Anim., p. 197.
     BLACK RAT, Penn., Arc.  Zool., vol. i., p. 129.
     ROLLER PONTOPP., Dan.  i., p. 611.
     MUS RATTUS, Griffith's Animal Kingdom, vol. v., 578, 5.
     MUS RATTUS, Harlan, p. 148.
     MUS RATTUS, Godman, vol. ii., p. 83.
     MUS RATTUS, Richardson, p. 140.
     MUS RATTUS, Emmons, Report on Quadrupeds of Massachusetts, p. 63.
     MUS RATTUS, Dekay, Natural History of New-York, vol. i., p. 80.


                                  DESCRIPTION.

     Head, long; nose, sharp pointed; lower jaw, short; ears, large, oval, broad
and naked.  Whiskers, reaching beyond the ear.
     Body, smaller and more delicately formed than that of the brown rat;
thickly clothed with rigid, smooth, adpressed hairs.
     Fore-feet, with four toes, and a claw in place of a thumb.  Feet,
plantigrade, covered on the outer surface with short hairs.  Tail, scaly,
slightly and very imperfectly clothed with short coarse hairs.  The tail becomes
square when dried, but in its natural state is nearly round.  Mammae, 12.


                                    COLOUR.

     Whiskers, head, and all the upper surface, deep bluish-black; a few white
hairs interspersed along the back, giving it in some lights a shade of
cinereous; on the under surface it is a shade lighter, usually cinereous.  Tail,
dusky; a few light-coloured hairs reaching beyond the toes, and covering the
nails.


                                  DIMENSIONS.

                                                               Inches.

   Length of head and body  .  .  .  .  .  .  .  .  .  .  .  .   8
   Length of tail  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .   8 1/4


                                    HABITS.

     The character of this species is so notoriously bad, that were we to write
a volume in its defence we would fail to remove those prejudices which are every
where entertained against this thieving cosmopolite.  Possessing scarcely one
redeeming quality, it has by its mischievous propensities caused the world to
unite in a wish for its extermination.
     The Black Rat is omnivorous, nothing seeming to come amiss to its voracious
jaws--flesh, fowl or fish, and grain, fruit, nuts, vegetables, &c., whether raw
or cooked, being, indiscriminately devoured by it.  It is very fond of plants
that contain much saccharine or oleaginous matter.
     The favourite abodes of this species are barns or granaries, holes under
out-houses or cellars, and such like places; but it does not confine itself to
any particular locality.  We have seen its burrows under cellars used for
keeping the winter's supply of sweet potatoes in Carolina, in dykes surrounding
rice-fields sometimes more than a mile from any dwelling, and it makes a home in
clefts of the rocks on parts of the Alleghany mountains, where it is very
abundant.
     In the neighbourhood of the small streams which are the sources of the
Edisto river, we found a light-coloured variety, in far greater numbers than the
Black, and we have given three figures of them in our Plate.  They were sent to
us alive, having been caught in the woods, not far from a mill-pond.  We have
also observed the same variety in Charleston, and received specimens from Major
LECONTE, who obtained them in Georgia.
     During the summer season, and in the autumn, many of these rats, as well as
the common or Norway rat, (Mus decumanus,) and the common mouse, (Mus musculus,)
leave their hiding places near or in the farmer's barns or hen-houses, and
retire to the woods and fields, to feed on various wild grasses, seeds, and
plants.  We have observed Norway rats burrowing in banks and on the borders of
fields, far from any inhabited building; but when the winter season approaches
they again resort to their former haunts, and possibly invite an additional
party to join them.  The Black Rat, however, lives in certain parts of the
country permanently in localities where there are no human habitations, keeping
in crevices and fissures in the rocks, under stones, or in hollow logs.
     This species is by no means so great a pest, or so destructive, as the
brown or Norway rat, which has in many parts of the country either driven off or
exterminated it.  The Black Rat, in consequence, has become quite rare, not only
in America but in Europe.
     Like the Norway rat this species is found of eggs, young chickens, ducks,
&c., although its exploits in the poultry house are surpassed by the audacity
and voraciousness of the other.
     We have occasionally observed barns and hen-houses that were infested by
the Black Rat, in which the eggs or young chickens remained unmolested for
months together; when, however, the Rats once had a taste of these delicacies,
they became as destructive as usual, and nothing could save the eggs or young
fowls but making the buildings rat-proof, or killing the plunderers.
     The following information respecting this species has been politely
communicated to us by S. W. ROBERTS., Esq., civil engineer:--
     "In April, 1831, when leading the exploring party which located the portage
railroad over the Alleghany mountains, in Pennsylvania, I found a multitude of
these animals living in the crevices of the silicious limestone rocks on the
Upper Conemaugh river, in Cambria county, where the large viaduct over that
stream now stands.  The county was then a wilderness, and as soon as buildings
were put up the rats deserted the rocks, and established themselves in the
shanties, to our great annoyance; so that one of my assistants amused himself
shooting at them as he lay in bed early in the morning.  They ate all our shoes,
whip-lashes, &c., and we never got rid of them until we left the place."
     We presume that in this locality there is some favourite food, the seeds of
wild plants and grasses, as well as insects, lizards, (Salamandra,) &c., on
which these Rats generally feed.  We are induced to believe that their range on
the Alleghanies is somewhat limited, as we have on various botanical excursions
explored these mountains at different points to an extent of seven hundred
miles, and although we saw them in the houses of the settlers, we never observed
any locality where they existed permanently in the woods, as they did according
to the above account.
     The habits of this species do not differ very widely from those of the
brown or Norway rat.  When it obtains possession of premises that remain
unoccupied for a few years, it becomes a nuisance by its rapid multiplication
and its voracious habits.  We many years ago spent a few days with a Carolina
planter, who had not resided at his country seat for nearly a year.  On our
arrival, we found the house infested by several hundreds of this species; they
kept up a constant squeaking during the whole night, and the smell from their
urine was exceedingly offensive.
     The Black Rat, although capable of swimming, seems less fond of frequenting
the water than the brown rat.  It is a more lively, and we think a more active,
species than the other; it runs with rapidity, and makes longer leaps; when
attacked, it shrieks and defends itself with its teeth, but we consider it more
helpless and less courageous than the brown or Norway rat.
     It is generally believed that the Black Rat has to a considerable extent
been supplanted both in Europe and America by the Norway rat, which it is
asserted kills or devours it.  We possess no positive facts to prove that this
is the case, but it is very probably true.
     We have occasionally found both species existing on the same premises, and
have caught them on successive nights in the same traps; but we have invariably
found that where the Norway rat exists in any considerable numbers the present
species does not long remain.  The Norway rat is not only a gross feeder, but is
bold and successful in its attacks on other animals and birds.  We have known it
to destroy the domesticated rabbit by dozens; we have seen it dragging a living
frog from the banks of a pond; we were once witnesses to its devouring the young
of its own species, and we see no reason why it should not pursue the Black Rat
to the extremity of its burrow, and there seize and devour it.  Be this as it
may, the latter is diminishing in number in proportion to the multiplication of
the other species, and as they are equally prolific and equally cunning, we
cannot account for its decrease on any other supposition than that it becomes
the prey of the more powerful and more voracious Norway rat.
     The Black Rat brings forth young four or five times in a year; we have seen
from six to nine young in a nest, which was large and composed of leaves, hay,
decayed grasses, loose cotton, and rags of various kinds, picked up in the
vicinity.


                           GEOGRAPHICAL DISTRIBUTION.

     This species is constantly carried about in ships, and is found, although
very sparingly, in all our maritime cities.  We have met with it occasionally in
nearly all the States of the Union.  On some plantations in Carolina,
particularly in the upper country, it is the only species, and is very abundant.
We have, however, observed that in some places where it was very common a few
years ago, it has altogether disappeared, and has been succeeded by the Norway
rat.  The Black Rat has been transported to every part of the world where men
carry on commerce by means of ships, as just mentioned.


                                GENERAL REMARKS.

     PENNANT, KALM, LINNAEUS, PALLAS, DESMAREST, and other European writers,
seem disposed to consider America the Fatherland of this pest of the civilized
world.  HARLAN adopted the same opinion, but BARTRAM, (if he was not
misunderstood by KALM,) did more than any other to perpetuate the error.
     In the course of a mutual interchange of commodities, the inhabitants of
the Eastern and Western Continents have presented each other with several
unpleasant additions to their respective productions, especially among the
insect tribe.
     We are willing to admit that the Hessian fly was not brought to America in
straw from Hanover, as we sought in vain for the insect in Germany; but we
contend that the Black Rat and the Norway rat, which are in the aggregate
greater nuisances, perhaps, than any other animals now found in our country,
were brought to America from the old world.  There are strong evidences of the
existence of the Black Rat in Persia, long before the discovery of America, and
we have no proof that it was known in this country till many years after its
colonization.  It is true, there were rats in our country which by the common
people might have been regarded as similar to those of Europe, but these have
now been proved to be of very different species.  Besides, if the species
existed in the East from time immemorial, is it not more probable that it should
have been carried to Europe, and from thence to America, than that it should
have been originally indigenous to both continents?  As an evidence of the
facility with which rats are transported from one country to another, we will
relate the following occurrence:  A vessel had arrived in Charleston from some
English port, we believe Liverpool.  She was freighted with a choice cargo of
the finest breeds of horses, homed cattle, sheep, &c., imported by several
planters of Carolina.  A few pheasants (Phasianus colchicus) were also left on
board, and we were informed that several of the latter had been killed by a
singular looking set of rats that had become numerous on board of the ship.  One
of them was caught and presented to us, and proved to be the Black Rat.  Months
after the ship had left, we saw several of this species at the wharf where the
vessel had discharged her cargo, proving that after a long sea voyage they had
given the preference to terra firma, and like many other sailors, at the
clearing out of the ship had preferred remaining on shore.
     We have seen several descriptions of rats that we think will eventually be
referred to some of the varieties of this species.  The Mus Americanus of
GMELIN, Mus nigricans of RAFINESQUE, and several others, do not even appear to
be varieties; and we have little doubt that our light-coloured variety, if it
has not already a name, will soon be described by some naturalist who will
consider it new.  To prevent any one from taking this unnecessary trouble, we
subjoin a short description of this variety, as observed in Carolina and
Georgia.
     Whole upper surface, grayish-brown, tinged with yellow; light ash beneath;
bearing so strong a resemblance to the Norway rat, that without a close
examination it might be mistaken for it.
     In shape, size, and character of the pelage, it does not differ from the
ordinary black specimens.