Injurious and Beneficial Insects. 



to Western naturalists for information regarding its habits, as it 

 is a comparatively new insect to this State. 



It was imported from Europe into nurseries at Rochester, New 

 York, during the year 1860. It seems since that time to have 

 spread westward and eastward, arriving in Eastern Massachu- 

 setts about 1865, as I am informed by Mr. F. G. Sanborn. For 

 two seasons past it has been very destructive in gardens in 

 Essex County. 



The parent of this worm is a saw fly, so named from bearing a 

 saw-like sting, or ovipositor, with which it pierces the leaves or 

 stalks of plants, cutting a gash, in which it deposits an egg, the 

 egg passing out from the ovary through the oviduct, and thence 

 through the blades of the ovipositor into the wound made in the 

 plant. While most of the members of this family cut a gash in 

 the leaf, into which an egg is pushed, a few, as in the present 

 insect, simply place them on the under surface of the leaf, as 

 seen in Fig. 1. (1) The fly has four wings, and belongs to the 

 same group of insects (Hymenoptera) that comprises the bee, 

 wasp, and ichneumon fly. 



The following account of its habits is taken from the writer's 

 Guide to the Study of Insects : " There are about fifty species 

 of Nematus in this country, 

 of which the nfost injurious 

 one, the Gooseberry saw fly, 

 has been brought from Eu- 

 rope. Professor Winchell, 

 who has studied this insect 

 in Ann Arbor, Mich., where 

 it has been very destructive, 

 observed the female on the 

 16th of June, while deposit- 

 ing her cylindrical, whitish 

 and transparent eggs in reg- 

 ular rows along the under 

 side of the veins of the leaves, at the rate of about one in forty- 

 five seconds. The embryo escapes from the egg in four days. 

 It feeds, moults and burrows into the ground within a period of 

 eight days. It remains thirteen days in the ground, being 

 most of the time in the pupa state, while the fly lives nine days. 



