BLACK RAT. 191 



for keeping the winter's supply of sweet potatoes in Carolina, in dykes 

 surrounding rice-fields sometimes more than a mile from any d^velling, 

 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 Norw^ay rat, (Mus decmnanus,) and the common 

 mouse, (Mus musculus,) leave their hiding places near or in the farmer's 

 bams or hen-houses, and retire to the ^voods and fields, to feed on various 

 wild grasses, seeds, and plants. We have observed Norway rats bur- 

 rowing in banks and on the borders of fields, far from any inhabited 

 building ; but when the w^inter 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 

 bro\\Ti 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 fond of eggs, young chickens, ducks, 

 &c., although its exploits in the poultry house are surpassed by the au- 

 dacity 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 unmo- 

 lested 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 kill- 

 ing the plunderers. 



The following information respecting this species, has been politely 

 communicated to us by S. W. Roberts, Esa., 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 countv was then a wilder- 



