NATURAL HISTORY. 



839 



the genus. It is of nearly the same 

 size with the aphis rosa;, but of a 

 pale greenish yellow colour, with a 

 row of black, ciescfivt-shapcd spots 

 down each side of the abdomen, and 

 a black stripe on each side the tho- 

 rax : the wings are beautifully 

 iransparent, with brown nerves or 

 ■\eins, a black edging down the 

 shoulder-part, and several dusky 

 patches toward the tips. 



In the sixth volume of the trans- 

 actions of the Linnaan society of 

 London, we lind an excellent paper 

 on the subject of these animals by 

 the late ingenious Mr. Curtis. " The 

 ' leaves (says he) of such trees and 

 ' plants as have a firm texture and 

 ' strong fibres, though infested with 

 ' theie insects, preserve their form; 

 ' but the more tender foliage of 

 ' others, and flowers in general, 

 ' cannot bear their punctures witli- 

 ' out curling up and becoming ilis- 

 ' torted : in consequence of which 

 '• they lose their beauty entirely 

 ' and irretiievably. The cultiva- 

 ' tors of plants, especially in stoves 



• and greenhouses, cannot be too 

 ' much on their guard .-gainst the 

 ' whole trib'! of aphides ; for with 

 'what pleasure can a large choice 

 ' collection be viewed, when there 

 ' IS scarcely a plant but what exhi- 

 ' bits symptoms of disease occasion- 

 ' ed by vermin ?" 



" As the species of this genus are 

 ' very numtrous, and adord but 



• few marks of distinction, Lin- 

 ' na^us has contented himself wilh 

 ' giving most of them trivial names, 

 ' according to the particular plant on 

 ' which they are found : a close at- 

 ' tcntion to them h ill, however, «lis- 

 ' clo>e more distinctive characters 

 ' than naturalists are aware of. Of 

 ' some of the circumstances at- 

 ' tcndunt ou the piopagaliun of 



" these minnte animals accounts are 

 " related, deviating so wonderfully 

 '• from the common course of na- 

 " turs, that they could not be cre- 

 '' dited, were not the authors of 

 " them known to be men of the 

 " nicest and most accurate observa- 

 " tion, and of the strictest veracity. 

 " On this part of the subject I have 

 " little to say from my own obser- 

 " vation, but as some account of so 

 " extraordinary a part of their his- 

 " tory may be expected in a paper 

 " of this sort, I shall state the facts, 

 "simply observing, that neither ia 

 " the aphis salicis, which at times I 

 '' have watched with great atten- 

 " tion, nor in any other species of 

 " ap/iis, did 1 ever observe any 

 '' sexual intercourse to take place. 

 " Whether this may have arisen 

 " from the extreme infrequency of 

 " such a procedure, or from my not 

 " having observed these insects at ai 

 " proper time of the year, i know 

 " not ; but most undoubtedly such 

 " intercourse does not take place 

 " between the different sexes of 

 " aphis as in other insects. Yet 

 " Monsieur Bonnet, who may be 

 " said to have almost taken up his 

 " abode with these insects, informs 

 " us that he has frequently noticed 

 " such connection, which he de- 

 " scribes as taking place at one cer- 

 " tain time of the year only ; and 

 " that from a female thus impreg- 

 <' nated, many successive geuera- 

 " tions will be produced without 

 " any farther impreg\ia(it)n. He 

 " took the aphides as soon as 

 " brought forth, and kept each 

 " individual separate. The females 

 " ofsuch brought forth abund.incc 

 " of young, lie took the young of 

 " these, and treated tliem precisely 

 '' in the same manner. The pro- 

 " du(e was the same: and tliushe 

 3 11 4 " proceeded 



