JOINTWORM FLIES. 



a 



d 



were collected in Ontario, Canada. Tliere are specimens in the 

 Harris collection of the Boston Society of Natural History bearing 

 the label Isosoma tritici that were collected in Virginia in 1852. 

 There are also speci- 

 mens of tritici in the 

 same lot. As late as 

 1892 F. M. Webster 

 (13) stated that— 



He had not reared tlie 

 depredator, and though iu 

 many respects the attack 

 seemed to agree with that 

 of Isosoma hordei, as de- 

 scribed by Harris and Fitch, 

 yet in many other features 

 it appeared different. In 

 all cases — and he laad ex- 

 amined hundreds of wheat 

 straws from northern 

 Ohio — the attack was al- 

 ways above the upper joint. 

 In two cases the upper joint 

 and the one below had been 

 attacked. From many thor- 

 ough examinations he had 

 found that the stem itself 

 had not been eaten into, the 

 cells being formed in the 

 sheath, but owing to the 

 pressure of the galls on the 

 tender stem the latter had 

 become distorted and the 

 upper portion with the head, 

 where one was produced, 

 was greatly aborted. 



This so accurately de- 

 scribes the injury that 

 no doubt is left as to the 

 identity of the insect in 

 question or as to the fact 

 that the species was 

 very widespread and 

 may have been a more 

 serious pest in the early 

 days in Michigan and northern Ohio than H. t7%tici. This is 

 one of the reasons why entomologists had such . controversies over 

 tritici in the early days 

 132861°— 19 2 



Fio. 7. — Eggs of species of Harmolita : a, H. Ucspcrua ; 



It, II. wcbsteri] c, II. albomaculata ; d, H. grandls, 

 • form grandis, after oviposition ; e, H. grandis, form 



(jrandis, just before hatching. All greatly enlarged. 



(Original.) 



There is not the slightest doubt in the 



