INSECTS ATTACKING SMALL FRUITS. 



RASPBERRY SLUG. 

 {Selandria rubi Harris; Order, Hymenoptera.) 



.Duig)iosls. — Infesting raspberries ; dark-green, slug-like larvie, 

 about three-fourths of an inch long, feeding on the leaves, mostly 

 during May; the coarse veins of the leaves are not eaten. 



Description and Life-history. — The adult insect is a four-winged 

 saw-fly, with transparent wings expanding about one-half of an 

 inch. The veins of the wings are black. The front part of the 

 body is black, the abdomen dark reddish. The adults appear soon 

 after the young leaves are put forth, and insert their eggs beneath 

 the skin of the raspberry leaf near the ribs and veins. The newly- 

 hatched larva is small and whitish ; as 

 it grows older and larger it becomes 

 green; the full-grown larva, or "slug," 

 is from five-eighths to three-fourths of 

 an inch long, dark green, with slightly 

 yellowish tinge on the last two seg- 

 ments. A narrow, dark-green, longi- 

 tudinal, dorsal line extends from the 

 head to the last segment of the body. 

 The head is bright, shining green. The 

 liody bears many small, branched 

 spines, in length about one-fourth the 

 diameter of the slug. It has 11 pairs of legs. 



The larva is full-grown about June 1, and enters the ground, 

 where it constructs a thin, tough cocoon of particles of earth fast- 

 ened together by a sticky substance secreted by the larva. In 

 this cocoon the larva quietly remains unchanged through the fall 

 and winter, pupating in early spring, and emerging as the adult 

 saw-fly about the middle of April. 



Remedies. — Hand-picking is effective. White hellebore used 

 as a powder (see p. 10) and dusted on the vines, or mixed with 



(93) 



Fig. 51. Raspberry Slug: 

 a, larva; b, joints of larva, en- 

 larged, to show arrangement 

 of spiny hairs. 



