Mr. CuRTis's OhferviHiom on Aphicles. 8l 



fn moft fpecies of Aphides botli males and females acQuire wings 

 at certain fealoiis; but in this refpe£l they aje fiibjcft to great vari- 

 ation, there being feme males and fome females that never have 

 wings; again, there are fbme females that become wingctl, while 

 others of the fame fpecies do not. 



In the quality of the excrement voided by thefe infects there is 

 fomething wonderfully extraordinary. Were a perfon accidentally 

 to take up a book in which it was gravely effLited that in fome 

 countries there were certain animals which voided liquid fugar, he 

 would foon lay it down, regarding it as a fabulous tale, calculated 

 to impofe on the credulity of the ignorant; and yet fuch is literally 

 the truth. 



The fupcrior fize of the AplmfiUcis \\-iII enable the moft common 

 obferver to fatisfy himfelf on this head. On looking fledfaftly for 

 a few minutes at a group of thefe inle<Sls while feeding on the bark 

 of the willow, one perceives a few of them elevate their bodies, and 

 a tranfparcnt fubilance evidently drop from them, which is imme- 

 diately followed by a fimilar motion and difcharge like a fmall (Hower 

 from a great number of others. At firft I was not aware that the 

 fubftance thus dropping from thefe animals at fuch ftated intervals 

 was their excrement, but was convinced of its being fo afterwards ; 

 for, on a more accurate examination, I found it to proceed from the 

 extremity of the abdomen, as is ufual in other infects. On placing- 

 a piece of writing-paper under a mafs of thefe infedls, it foon be- 

 came thickly fpotted ; holding it a longer time, the fpots united from 

 the addition of others, and the whole furface afTumed a glofly ap- 

 pearance. I tailed this fubflance, and found it to be as fwect as 

 fugar. I had the lefs hefitation in doing this, having obfcrved that 

 wafps, ants, flies, and infers without number, devoured it as 

 quickly as it was produced : but, were it not for thefe, it might nb 

 doubt be coUeded in confiderable quantities, and, if fubjefted to the 

 Vol. VL M proceflfes 



