344 FRUIT INSECTS 



The Green Currant Worm 

 Gymnonychus appendiculatus Hartig 



This is the so-called native currant worm, but as it too was 

 doubtless imported from Europe the name should be discarded. 

 It is widely distributed throughout the Northern states and 

 Canada, and while sometimes destructive in the West, it rarely 

 attracts attention in the East. 



The adults are smaller than in the preceding species, and in 

 both sexes the body is black. The flies appear in the spring 

 just as the leaves are unfolding, and the female inserts her 

 whitish eggs into the edge of the currant or gooseberry leaf 

 between the two outer layers. The egg swells considerably 

 before hatching and produces a distinct blister-like elevation 

 of the epidermis of the leaf. They hatch in about five days, 

 and the young larvae feed singly on the edge of the leaf, not in 

 colonies, as in the preceding species. The larvae are of a uni- 

 form light green color and have blackish heads ; they lack the 

 black spots characteristic of the foregoing species and are con- 

 siderably smaller. They become full-grown in about 12 days 

 and spin small brownish cocoons beneath leaves or trash or 

 slightly below the surface of the ground ; the flies emerge in 

 about a week. In New York there may be four or five broods, 

 each generation requiring about twenty-five days from egg to 

 adult. 



Whenever this currant worm becomes troublesome, it may 

 be controlled by spraying with either 1 pound Paris green or 4 

 pounds arsenate of lead in 1 00 gallons of water at the first ap- 

 pearance of the worms. When the fruit is ripening use helle- 

 bore, 4 ounces in 2 or 3 gallons of water, or dry 1 pound in 5 

 pounds of flour or air-slaked fime. 



References 

 Walsh, Pract. Ent. I, pp. 122-124. 1866. 

 Saunders, Kept. Ent. Soc. Ont. f. 1871, p. 34. 1872. 



