DIPT!:RA. 99 



wood. "The wart-like gal common on the meadow- 

 sweet {Spiraea) ; the uneve, wellings on the stalks and 

 leaves of the stinging-nettle the little furry purses on 

 the ground-ivy ; the woody, shapeless excrescences on 

 the raspberry plants ; the ^'uder upright growth on 

 beech leaves; the blisters « i bed straw, yellow nettle, 

 and others ; the knots withi che very blossoms of many 

 flowers — all these, and a gre many more, are the work 

 of little creatures in this nu -lerous family" (Staveley). 



On Plate IV. (Fig. 1) will be seen a magnified drawing 

 of the Wheat-midge {Gecidomyia tritici), the larvae of 

 which occasionally do much mischief to the wheat crops. 

 This insect is a near relative of the Hessian-fly, the North 

 American scourge, whose ravages have even caused 

 famine in the land. The larvae of the Wheat-midge 

 feed on the flower of the wheat, rendering it abortive. 

 The eggs are laid in June, the larvae changing to pupae 

 upon the sound grains and inner valves, or entering the 

 ground for that purpose, the perfect insects hatching in 

 the summer. 



The Blhionidw I have represented on Plate IV., Fig. 8, 

 by the well-known Bihio Marci, the Hawthorn-fly of the 

 angler, whose deep black bodies and white wings of the 

 male, and long legs pointing backwards, must be familiar 

 to the most unobservant. The larvae feed on the roots 

 of grass ; they are worm-like and cylindrical, with 

 tmnsverse rows of short hairs, serving for locomotion ; 

 the pupae are naked, enclosed in a smooth oval cell. 

 The perfect insect appears towards the end of April, 

 about St. Mark's day, hence the specific name of the 

 insect Marci. 



The Slmulidw, Chironomydw, and Cidicidw, are emi- 



H 2 



