THE MONTHLY BULLETIN. 245 



one fiftieth of an inch long, cylindrical and shining red. The maggots 

 are greenish-white in color and work between the sheaths and stems of 

 the host. The pnparia are rich brown and located among the roots at 

 the bases of the plants. 



Life History. — The adults appear in the fall and deposit their eggs 

 upon the stems of the young growing wheat as soon as it is well above 

 the ground. The larvae work between the blade sheath and stem during 

 the winter, changing to puparia in the spring and to adults a little 

 later. These adults, known as the spring brood, lay eggs in the growing 

 stalks, weakening and causing them to fall. After the grain is cut the 

 maggots remain in the stubble, transforming into adults, known as 

 the fall brood, which lay their eggs upon the young growing wheat. 



Distribution. — This insect was introduced into the central part of 

 the State many years ago but for some reason has spread very little 

 and in no sense become at all a serious pest. 



Food Plants. — Wheat is the crop most seriously injured by this pest 

 and the damage done to that crop in the central wheat-growing states 

 has been tremendous. It also Avorks on Elymus sp. and Agrostis sp. 



Control. — Fortunately the ravages of this fly in California have not 

 been great and it is to be hoped that it will never become a serious pest 

 Tiere. Control is extremely difficult, consisting in burning and plow- 

 ing under the stubble as soon as the wheat is cut and planting as late 

 in the fall as possible. Early trap crops of wheat are also planted 

 about August. Such crops attract the flies and after the eggs are laid 

 they are plowed under, destroying the oncoming broods. 



Natural Enemies.- — Parasites also play an important part in the 

 ■control of the pest. In the Eastern States the parasite, Merisus des- 

 tructor works upon it. The internal parasite, Semiotellus destructor, 

 has been bred from the flv in California. 



SYRPHID^. 



FLOWER, HONEY OR SWEAT FLIES. 



Always among the plant lice are to be found greenish, flat, sticky- 

 looking "worms" which are decidedly pointed at one end and do 

 not have distinct head, eyes or legs. These so-called "worms" are 

 the larvae or maggots of flies belonging to the family SyrphidcB, which 

 are commonly called syrphid or flower-flies. The larvge vary from the 

 minutest first-hatched maggot to nearly an inch in length, according to 

 the species to which they belong. They are usually light or dark green, 

 but some may be brown, orange, very light or nearly black. Those feed- 

 ing upon plant lice and herein described are green with a longitudinal 

 darker green or brownish stripe on the dorsum. The mouth is situated 

 at the small end and all of the food is obtained by puncturing the body 

 Myalls of the lice and then sucking out the contents. This operation is 



