MAMMALIA. FERA. 
SciUEUS. 
The late Mr White of Selborne (discovered this species in 1767. From his 
observations, Mr Pennant appears to have drawn up his description in the 
Brit. Zool. i. p 121. without acknowledging the source of his information. 
According to Mr White, “ they never enter into houses; are carried into 
ricks and barns with the sheaves ; abound in harvest ; and build their nests 
amidst the straws of the corn above the ground, and sometimes in thistles. 
They breed as many as eight at a litter, in a little round nest composed of 
the blades of grass and wheat.” In winter they burrow deep in the earth, 
or lodge in oat ricks. Montagu has found them in the latter situation in the 
colder months without any signs ot torpidity. They are the smallest of Bri- 
tish quadrupeds, not exceeding in weight |th of an ounce. 
b. RATS. 
27. M. Rattus. Black Rat. — Fur greyish-black above, paler 
coloured beneath ; body eight, and the tail nine inches in length. 
M. major seu Sorex, Merr. Pin. p. 167 — Sibb. Scot. p. 12 — Ray^ Quad, 
p. 217 — Penn. Brit. Zool. ii. p. 113. W, Llygoden fferngig; Boof- 
rotten — Infests houses. 
This is a voracious animal, living in houses, barns, and granaries, and de- 
vouring all sorts of provisions. I have evidence of their bringing forth eleven 
young ones at a litter, and of their pulling the hair olF the ne(3cs of cows to 
line their nests. The remarks of Mr Pennant have led to the supposition 
that this species is now nearly extirpated by the brown rat, which he consi- 
dered as its natural enemy. He does not mention his evidence of enmity 
between the species. On the contrary, I know that they have lived for 
years under the same roof, the brown rat chiefly residing in holes of the 
floor, the other chiefly in holes in the roof. The period of their extirpation 
is far distant. They still infest the older houses of London and Edinburgh, 
and in many districts of the country they are common. 
28. M. decumanus. Brown Rat. — Fur yellowisli-brown 
above, beneath grey ; body about nine inches, with a tail of 
equal length. 
Penn. Brit. Zool. 1. 115. — M. fossor. Walker's Essays, p. 497- S, Grund- 
rotten. 
This species is not so nimble as the former, but it is stronger and bolder ; 
the nose is more obtuse, and the hair on the feet thinner. It burrows under 
the foundations of houses, but prefers being near drains of foul water. It 
swims with ease, and infests ships and harbours. It brings forth as many as 
nineteen at a litter. This species is generally believed to have been im- 
ported into this country about the middle of the last century, some say from 
Norway, whence it has been termed Norway rat, others from Antwerp, or 
from America. It is now, however, more generally considered as of Asiatic 
origin. Linnaeus seems to have confounded this species with the former in 
the description in his Syst. Nat. p. 83. According to the observations of Mr 
Wilson, the rats of I.ondon are very subject to urinary calculi ; Annals of 
Phil. vol. ix. p. 319. 
Gen. XVIII. SCIURUS. Squirrel.— Incisors with chisel- 
shaped summits ; grinders four on each side in both jaws ; 
four fingers and five toes. 
29. S. vulgaris. Common Squirrel. — Fur brownish-red 
above, beneath white ; ears tufted with long hairs ; length of 
the body about 18 inches. 
