JOINTWORM FLIES. 17 



stems in New York in 1888. It is supposed that caftiva was the 

 species involved in the hitter case, but doubt is cast upon this sup- 

 position by Lintner's statement that part of the specimens were 

 typical hordei (tritici), and part were much larger, the latter being 

 captiva. The species the writer knows as captiva is much smaller 

 than tritici; besides, captiva has been reared from galls in blue- 

 grass, and should it breed in wheat also it will be the second species 

 known to infest plants belonging to separate and distinct genera. 

 This is not at all impossible but at present it seems improbable. 

 As the New York case is the only one recorded where the species 

 has been reared from wheat it seems reasonable to suppose that 

 another species than captiva was involved. 



The writer reared specimens of captiva from galls in blue-grass 

 collected near Richmond, Ind., in 1905. It has not been reared 

 since. " Nothing is known of its life history except that it un- 

 doubtedly has only one generation a year and that both males and 

 females were reared. The galls (PL III, D) occur near the base of 

 the seed stalk where the stem is thick. As the seed stalks of blue- 

 grass are slender and rather frail the stem at the point where the 

 galls occur does not seem to be very woody. The cells are arranged 

 in a row end to end, there being insufficient room, apparently, for 

 the larvae to have cells side by side in the stalk as in some other 

 species. 



THE BLUE-GRASS STRAW-WORM.i 



The blue-grass straw-worm was described only recently by the writer 

 and W. T. Emery (10, p. 445) but undoubtedly has been breeding in 

 blue-grass {Poa pratensis) for years. Very probably it has been 

 confused with H. captiva and perhaps with other species. The fi]'st 

 records of poae are by F. M. Webster and the writer in 1905. It is 

 a widely distributed species and doubtless can be found wherever 

 blue-grass grows normally. 



MANNER OF INJURY. 



The writer has never had the opportunity to visit sections that 

 grow blue-grass seed to learn to what extent infestation exists. The 

 only infestation found has been where the grass grows wild in pro- 

 tected places, such as along fences. Pastures usually are kept cropped 

 ■close by stock and there is little chance for poa^^ to breed. It works 

 in the center of the stem and undoubtedly would injure the seed 

 crop greatly, as the seed stalks of blue-grass are slender, soft, and 

 rather fragile, not at all hard and woody like the majoritj^ of the 

 grasses affected by other species. The cavity in the stem is scarcely 



^ Harmolita poae Phillips and Emery. 



