Mr. Marsham'j further Obfcrvatwm on the Wheat Infecl. 225 



of the flower, until the feed was ripe ; and the refult of their unre- 

 mitted endeavours, with a few of-my own obfervations, I now lay 

 before you, requeuing, that if you think them worthy their atten- 

 tion, you will prefent them to our valuable Society ; for fuch I 

 think it may be truly ftyled, fince the opinion of the Public has fo 

 fully ftamped its confequence. 



Mr. Markwick, in a letter to me dated the 17th July 1797, 

 Hates as follows :— " On the 12th of this month I firft difcovered 

 fome of the little flies (which I fend you inclofed) fitting between 

 the hufks or clefts of the ears of wheat : the next day they ap- 

 peared to me more abundant; and then, for the firft time, I found a 

 few of the fmall yellow larvae, which infefted the wheat in the 

 year 1795, fitting clofe to the ftamina, exadly as they are repre- 

 fented in the 3d vol. of the Linnaan Tranfadiions,^^ 251. Tab. 22. 

 fig. 10. a ; fince that time I have found the larvae in much greater 

 abundance, and the fly is alfo to be feen, though I think not in 

 fuch great numbers. The other infeds which I have difcovered 

 on the wheat, are the Thrips phyfapus, in its larva and perfeft ftate, 

 as in the year 1795 ; and fome of the ears were infefted with the 

 plant loufe (Aphis) called here the Dolphin." On the 25th of 

 July, I received alfo a letter from Mr. Kirby, that contained fome 

 valuable hints, which induced me to fend a copy of it to Mr. Mark- 

 wick ; and on the 17th of September I was favoured with the fol- 

 lowing letter from that gentleman : — 



" I want words to exprefs the pleafure I received from your laft let- 

 ter, as well as from your obliging communication of that of your very 

 ingenious and learned friend Mr. Kirby, and fhould have acknow- 

 ledged the obligation fooner, but waited until the end of harveft, 

 with the ill-founded hope of having fomething to communicate re- 

 lative to our little infe& worthy of your notice; for I am forry to fay, 



Vol. IV, Gg that 



