228 Introductory View of the 



to the genus Cecidomyia, though it does not, like the other 

 species, produce galls in the plants it infests. To this same 

 genus the Hessian fly, according to Mr. Say, also belongs, and 

 he names it Cecidomyia destructor (^). 



The antennae of the male are shorter than the body, some- 

 what slenderer towards the tip, with hairs in whorls, monili- 

 form, with the joints connected by a transparent thread. The 

 head and thorax are black ; breast sometimes fulvous ; wings 

 black, fulvous at the base, fringed, longer than the abdomen ; 

 legs pale, covered with black hairs ; abdomen brownish. In 

 the female, the joints of the antennae are not connected by a 

 transparent thread, and the abdomen is fulvous, with a dorsal 

 and ventral black interrupted vitta. 



A species of Ceraphron (C. destructor) deposits its eggs in 

 the larva, and keeps this destructive little pest within due 

 limits, otherwise Mr. Say supposes that the crops of wheat 

 would be totally annihilated. The female deposits from one to 

 eight or more eggs upon a single plant of wheat, between the 

 vagina of the inner leaf and the culm nearest the roots ; in 

 which situation, with its head towards the root or first joint, 

 the young larva passes the winter. They eat the stem, which 

 thus becomes weak, and breaks. 



This species, and C. ^ritici above mentioned, from their 

 causing no galls, appear to form a distinct group in the genus 

 Cecidomyia, with which, however, they agree in the characters 

 assigned to it by Meigen. 



As few entomologists appear to have been aware of the 

 above discovery of Mr. Say's, I hope this short account of it 

 will not be unacceptable to your readers. 



I am, Sir, yours, &c. 



Wm. Kirby. 



Art. VII. An Introductory Vie'vo of the Linnean System of 

 Plants, By Miss Kent, Authoress of Flora Dom^sticaf Sylvan 

 Sketches, &c. ^ t . ' 



The vegetable world was so little known in ancient times, 

 that the number of plants described by the Greek and Roman 

 writers does not exceed fourteen hundred ; less than a thir- 

 tieth part of the number now known. Some allowance, per- 

 haps, should be made for the fact, that some modern botanists 

 have multiplied species, by so denominating mere varieties ; 

 while it is most probable that, in ancient times, many distinct 

 species were confounded together. Still the number of plants 



