INSECTS ATTACKING FLOWERS. 107 



Description and Life-history. (For illustration see Fig. 51, 

 which shows the Raspberry Slug, a closely-allied form.) The 

 adult insect is a four-winged fly, belonging to the family of saw- 

 flies, in the same order with the ants, bees, and wasps. Its wings 

 are transparent, and expand about one-half of an inch. The 

 body is blackish. 



The eggs are laid under the skin of the rose leaf (the saw-flies 

 are so named because the females have a peculiar, saw-like, egg- 

 laying apparatus, by means of which the eggs are laid in small 

 incisions in the food-plant), and the larvse, or young slugs, hatch 

 in about two weeks. 



The larvae are not full-grown until about three weeks have 

 passed, during which time they feed voraciously on the leaves. 

 The slug has a small, yellowish head, with a black dot on each 

 side of it, and has 11 pairs of short legs. When young, the 

 body is semi-transparent and green ; when older, the body is more 

 opaque and has a yellowish color. The skin of the back is wrink- 

 led, and covered with minute points. In feeding, they do not 

 eat entirely through the leaf, but leave the veins and lower skin 

 intact, eating only the upper surface. The leaves are, of course, 

 killed, and a badly-infested rose-bush appears as if scorched by 

 fire. The feeding is done mostly by night and on dark days ; at 

 other times the slugs rest on the under side of the leaves. 



When the larvae are full-grown they drop to the ground, dig 

 into it, and pupate within a silk-lined cell. They emerge as 

 adults the following spring. 



Remedies. White hellebore (see p. 10) or pyrethrum (see p. 9) 

 may be dusted on the leaves, or may be sprayed on. Use two 

 tablespoonfuls of white hellebore to a bucket of water. If the 

 insecticides are to be dusted on, choose a time when the leaves are 

 damp with dew. 



Mr. Garman, entomologist at the Kentucky State College, has 

 used London purple (see p. 8) and Paris green (see p. 7) with 

 good effect. He used one pound of the dry poison to 100 gallons of 

 water. These poisons cannot be sprayed on the bushes after the 

 flower-buds unfold without destroying the petals. 



Kansas Notes. This pest is well known in rose gardens through- 

 out the State. 



