94 



The following account of its habits is quoted from the Guide to 

 the Study of Insects : "There are fifty species of Nenaatus in this 

 country, of which the most injurious one, the gooseberry sawfly, has 



Fig. l. 



been brought from Europe. 

 This is the N. vcntricosus of 

 Klug, which was undoubt- 

 edly imported into this 

 country about the year 1860, 

 spreading mostly from Roch- 

 ester, N. Y., where there 

 are extensive nurseries. 

 Prof. Winchell, who has 

 studied this insect in Ann 

 Arbor, Mich., where it has 

 been very destructive, ob- 

 served the female on the 

 16th of June, while depos- 

 iting her cylindrical, whitish 

 and transparent eggs, in 

 regular rows along the un- 

 der 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 



Fig. 2. 



feeds, moults and bur- 

 rows into the ground 

 within a period of eight 

 days. It remains thir- 

 teen days in the 

 ground, being most of 

 the time in the pupa 

 state, while the fly lives 

 nine days. The first 

 brood of worms ap- 

 peared May 21st; the 

 second brood June 

 25th. Winchell des- 

 cribes the larva as be- 

 ing pale-green, with 

 the head, tail and feet 

 black, with numerous 

 black spots regularly 

 arranged around the 

 body, from which arise two or more hairs. Figure 1 : 1, shows the 

 eggs deposited along the under side of the midribs of the leaf; 2, the 

 holes bored by the very young larvae ; and 3, those eaten by the larger 

 worms. 



