32 THE INSECT RECORD FOR I9OI 



June 4, with the statement that millions of them were to be 

 seen on the surface of Sunapee Lake, " all fish taken being 

 full of them." Mr. Laurence J. Webster sent specimens from 

 Holderness, May 27, with the report that they were " infest- 

 ing many shade and ornamental trees. In some cases they 

 eat the young leaves as they are coming out of the buds ; in 

 others they eat the fieshy stems, such as those of horse chest- 

 nut trees. On one white thorn shrub they have apparently 

 laid eggs on the inside of the rolled up leaves and have about 

 ruined the appearance of it for the season." Mrs. G. J. Jud- 

 kins also sent some of the flies from Bristol with the report 

 that they " almost made currant bushes black by their num- 

 bers during the first week in June. The\^ did apparently no 

 damage to the currants but treated the pansies shamefully." 

 In a later letter, the same writer sent peony buds believed to 

 have been injured by this same fly, and said : " They simply 

 ruined early flowers. If they have come to stay we will have 

 to fight for pansies, peonies, and the like." 



This bibio fly has been known as an abundant insect for a 

 long time. It has frequently been accused of injuries to 

 flowers and foliage, but careful studies have always shown 

 that the work of some other insect was attributed to it. It is 

 natural that its extraordinary abundance and its habit of rest- 

 ing upon flowers and foliage should lead to the inference that 

 any damage that may occur had been caused by it. But the 

 mouth parts of this fly are feeble, adapted to sipping the nec- 

 tar of flowers, rather than any more serious attack. It is out 

 of the question that they should eat young leaves or the fleshy 

 stems of trees, while it seems to me probable that the injury 

 to peonies and other flowers was due to the attack of the four- 

 lined leaf-bug, or the tarnished plant-bug, well-known pests 

 that blight flower buds and disappear from sight. The injury 

 to the white thorn shrub was pretty certainly due to aphides 

 or plant-lice, which commonly infest the leaves of this shrub. 

 For the eggs of this bibio fly are laid in masses at the surface 

 of the soil, especially in grass lands where there is much 

 decaying vegetation. They hatch into larvae that feed upon 

 this decaying vegetation throughout their life in this stage. 

 When full grown as larvae they change to pupas, and later 



