108 DIPTERA OF MINNESOTA. 



sown wheat, practically none, its life history may vary from that given 

 for the two above-named states. Prof. Lugger, in his First Annual 

 Report, handles the subject so nicely that we quote him in full: 



"According to the accounts given by the above-named entomologists, the 

 flies found in the wheat fields in September and October deposit their eggs 

 upon the young plants of winter wheat; the young maggots make their way 

 downwards, feeding upon the central part of the stem near the surface of the 

 ground, and cutting this ofif entirely, cause it to die. In these positions the 

 maggots hibernate, appearing again as adults in spring. These flies of the 

 first brood again deposit eggs, the maggots of which in time destroy the stems 

 just above the upper joints. After killing this upper part of the plants, an- 

 other brood of flies, the second generation, appears, which emerge in July 

 and deposit eggs in volunteer wheat or grass. From these maggots a third 

 brood is produced, which develop into flies the same autumn, and deposit 

 eggs upon the young plants of winter wheat. How many broods of this insect 

 may be produced in Minnesota is not known. Only one thing is certain, and 

 that is that their life history must be quite different in a region where volunteer 

 wheat is a very uncommon thing and where winter wheat is never grown. 

 It is true we have in such regions a number of grasses that might possibly 

 give this insect a shelter, as it is known to attack elsewhere, besides wheat, 

 such grasses as wild rye, blue-stem, poa and even green pigeon grass. Per- 

 haps this may be the case, though none of the wheat stem maggots have thus 

 far been found here in. such grasses. Here, at the Experiment Station, the 

 flies issued from material kept in breeding cages from July 22d till August 4th. 



"The illustration shows three straws of wheat infested by the maggot. It 

 shows also the pupa resting inside an open stem, and the injury caused by the 

 maggot. A fly, natural size, is resting upon one of the straws. Larva, pupa 

 and adult, greatly enlarged, are also shown. From many of the stems, instead 

 of flies, parasite.s issued, showing that, notwithstanding the hidden life led by 

 these maggots, their enemies can find them. 



"The adult flies, about one-eighteenth of an inch long, are of a pale yellow- 

 ish-green color. The large head is marked with a triangular black spot at base, 

 inside of which are located the three simple eyes. The large compound eyes 

 possess in life a beautiful bronze color. The thorax is marked with three 

 longitudinal bands. The abdomen is also ornamented with three longitudinal 

 bands, which are interrupted at the sutures, but more or less confluent toward 

 the posterior end. The color of the under side of the fly is uniformly yellowish 

 green, excepting two triangular spots on each side above the posterior and 

 middle coxae. The legs partake of the same general color; the thighs are 

 slightly darker, and the tibiae and tarsi dusky. The hind pair of thighs are very 

 much swollen, and are provided on the under surface with two rows of small 

 spines. - The hind tibiae are very strongly curved. The two large basal joints 

 of the antennae are yellowish. 



"The eggs of the American Meromyza are glistening white, with longi- 

 tudinal ridges, the space between the ridges is faintly recticulated. They af 



