RODENTIA—MURINAE—MUS RATTUS. 439 
The brown rat is well known over the world for its destructive propensities and the injury it 
causes to house and store. According to Pallas, it belonged originally to the warmer regions of 
Central Asia, Persia especially. Thence it crossed the Volga, in large troops, in 1737, peopled 
Russia, and subsequently overspread the whole of Europe. According to Erxleben, it reached 
England in 1730, and France in 1750. In 1775 it was taken to North America, some time 
subsequent to the black rat, which it soon drove out and nearly exterminated. At the present 
time no portion of the globe seems free from its pernicious presence, although, as it is usually 
transported in ships, its first foothold is on and near the seacoast. In 1851, Audubon and Bach- 
man spoke of it as not found on our Pacific coast. At the present time, however, it is very 
abundant there as far north as the Columbia river. 
List of specimens. 
5 Measurements. 
eRe = SS SSS 
= ea 5 3 =| S = 
5 |fzel - Locality. When col- |Whence and how obtained.| Nature of : a f & é 2 z 
= | 2 = ° S =| | S ° ct s 
et ie > lected. specimen. | > a 3 EI I 3 bey bas 
3 6 2 ® = 5 5 r-) 3 
5p a = ° ° Ss ° o ) a a 
2 n § ‘oe = = Ss ° = = 
3 |é 3 A a 2 2 | = 2 = 
° ° ° ° ‘3 
8/8 ja Pa ees Se SEE aS 
1567 | 2398 |....| Essex county, N. Y.....|.cesessccsees Dr. S. E. Hale 
BASH T900'| 5... locccieces dome saeco sees Aug.14,1855 | S. F. Baird........ 
1102 |......)++++| Middleboro’, Mass...... Noy. 5, 1855 
2816 |...... GO} Wethersfield, Ct....... 
RBLT | cescus | O |ecccccce Oe. cove 
QBS |. as. re) seed 0 
2819 |...... Gulessa eat do siseae 
1295 | 2097 Washington, D. C...... |eseessccecers 
1994 | 2096 | © |........ ones sees Go |leseoinsoadeine Se 
502 | 1637 foi easeceeeAQsvecccccsorcce | RED. 10,1000 |seeccsssccconsee 
2826 | 1120 |....| Washington, Miss...... eee Col. Wailes... 
=f] eecd SU boonence Gls sentoeesoeee seenechs GBhoccee 
2814 |. ...es 3 Petaluma, Cal.... E. Samuels.... 
BEI lances Q Pe sen 1Olai wate oa ado neectilbanoascnericcosc: 
B06 |.ccece «e--| Astoria, O. T....... «frose Lt. Trowbridge, U.S.A... 
Pit) meee | Steilacoom, W. T.....- aeeS ‘Gov. I. I. Stevens 
389 |...00. Q | Stockholm.........2+0 seseeseeseees| Swedish Acad 
1 Collected by Dr. Geo. Suckley, U. 8. A. 
MUS RATTUS, L. 
Black Rat. 
Mus rattus, Linnxus, Syst. Nat. I, 1766. 
DerKay, N.Y. Zool. I, 1842, 79. 
Aup. and Bacu. N. Am. Quad. I, 1849, 189; pl. xxiii. 
GuieBeEL, Saugt. 1855, 555. 
Mus americanus, DeKay, N.Y. Zool. I, 1842, 81; pl. xxi, f. 1. 
Mus nigricams, Raf. Am. Month. Mag. ITI, 1818, 446. 
Sr. Cu.—Tail about as long, or a little longer, than the head and body. Above, sooty black, passing insensibly into 
dark plumbeous on the belly ; sometimes a little paler. Feet brown; fur of the back without the longer coarse bristles of 
the brown rat. 
This species may be readily distinguished from the common brown rat by the much darker 
colors. In a specimen from Montreal, the upper parts are of a lustrous sooty black, with a green 
