CH. X.] THE PLANT-LOUSE. 183 



these insects, and we observe them endeavouring to 

 secrete themselves in the crannies of any neighbour- 

 ing- substance. Should the savoy cabbage be near 

 the trees whence they have been dislodged, the ca- 

 vities of the under sides of its leaves are commonly 

 favourite asylums for them. Multitudes perish by 

 these rough removals, but numbers yet remain ; and 

 we may find them in the nodes and crevices, on the 

 under sides of the branches, at any period of the 

 year, the long, cottony vesture being removed, but 

 still they are enveloped in a fine, short, downy 

 clothing, to be seen by a magnifier, proceeding appa- 

 rently from every suture, or pore of their bodies, and 

 protecting them in their dormant state from the mois- 

 ture and frosts of our climate. This aphis, in a na- 

 tural state, usually awakens and commences its la- 

 bours very early in the month of March; andthehoari- 

 ness on its body may be observed increasing daily : 

 but if an infected branch be cut in the winter, and kept 

 in water in a warm room, these aphides will awaken 

 speedily, spin their cottony vests, and feed, and 

 discharge, as accustomed to do in a genial season. 

 " It is often very difficult to ascertain the first ap- 

 pearance of many creatures not natives of our cli- 

 mate, though from the progress of science, and more 

 general observation, many things will be recorded. 

 The first visit of this aphis to us is by no means 

 clear. The epithet of American blight may be cor- 

 rectly applied ; but we have no sufficient authority 

 to conclude that we derived this pest from that coun- 

 try. Normandy and the Netherlands, too, have each 

 been supposed to have conferred this evil upon us ; 

 but extensively as this insect is spread around, and 

 favourable as our climate appears to be to its increase, 

 it bids fair to. destroy in progression most of our old- 

 est and long-esteemed fruit from our orchards. The 

 same unknown decree, which regulates the increase 

 and decrease of all created beings, influences this 

 insect; yet wet seasons, upon the whole, seem 



