THE ASPARAGUS MINER. 



white in color. 



The mines of the larvae about and below the bases of the stalks are 

 frequently so abundant that they have the effect of girdling, so that 

 the injured stalks can readily be pulled from the ground. 



DESCRIPTIVE. 



The parent insect is a two-winged fl}^ (fig. 1), metallic black, with 

 large prominent head and eyes, and clear wings, the wing expanse 

 being about one-sixth of an inch (4 mm.). 



The larva (fig. 2, a) is about one-fifth of an inch long and milk- 

 Like other maggots, it is footless, large at the 

 posterior extremity, and tapering 

 toward the head. 



The puparium (fig. 2, d, e) is not 

 unlike the "flaxseed" of the perni- 

 cious Hessian fly, with which it has 

 been aptly compared. At a little 

 distance, also, it suggests a Lecanium 

 scale. This stage is remarkable be- 

 cause of its peculiar flattened and 

 curved position, as seen from the 

 side. It is red in color, and meas- 

 ures about 3.5 mm. in length and 

 about 1 mm. in width. 



The egg has not been observed. 

 This species belongs to the dipter- 

 ous family Agromyzidse, and was described by Loew in 1861,*^ the 

 locahty being given as ''Middle States." 



DISTRIBUTION. 



In its injurious occurrences this species appears to be limited to the 

 eastern United States, from New England to Tennessee. From avail- 

 able data it is quite obvious, however, that it may be destructive over 

 a considerable territory, including a large portion of Massachusetts 

 and Connecticut, Long Island, the District of Columbia, Pennsyl- 

 vania, and Tennessee. As it is recorded from New Jersey, it is prob- 

 ably injurious there, although no reports of injury in that State have 

 reached this office. In time it will doubtless attract attention in 

 intermediate points and in States farther north and west. It has also 

 appeared in asparagus beds in California. 



HISTORICAL AND BIOLOGICAL NOTES. 



In May, 1897, and afterwards tliis fly was observed in abundance 

 by the writer on terminal shoots of asparagus, particularly at Cabin 

 John, Md. Two weeks later no more flies were seen, but June 26 



Fig. 2.— The asparagus miner {Agromyza sim- 

 plex): a, Larva, lateral view; b, thoracic spir- 

 acles; c, anal spiracles; d, puparium from side; 

 €, same from above; /, section of asparagus 

 stalk, showing injury and location of puparia 

 on detached section, a-e, Much enlarged: /, 

 slightly reduced. (Author's illustration.) 



tt Diptera Americse eeptentrionalis indigena, Centuria octava 84, p. 160. 



