THE CANADIAN ENTOMOLOGIST. 



39 



hatched larvae were found late in July. On hatching, the young 

 larvae bore through the sheath and penetrate to the young flower 

 buds inside. Here it commences to feed and to tie the unfolding 

 flowers together with silken threads, forming a slight silken tunnel 

 within which it feeds. When the head at length bursts open, it 

 may, therefore, be nothing but a mass of web with the caterpillars 

 inside. The larva feeds thus for about four weeks upon the seeds 

 and leaves of the plant, and then, having become nearly mature, 

 it crawls down the stem, usually to the axil of a leaf, where it eats 

 its way through the hollow stem and feeds for a few days until it 

 reaches maturity. When mature, the larva builds a light cocoon 

 of silk and excrement within which it changes to the pupal stage. 

 The total length of the larval life averages just under five weeks, 

 there being in all five larval instars. The pupal instar continues 

 for three weeks, most of the adults emerging during the latter 

 half of August, though a few belated individuals may not appear 

 until as late as the middle of September. The adults pass the 

 winter beneath the bark of trees, or in similar shelters. One 

 individual was found in the late winter hidden under a rafter in 

 a disused building on the outskirts of the College Farm. 



Of the number of insects reared from the egg to the adult 

 condition complete records were taken in the case of three indi- 

 viduals. This information is summarized in the following table: — 



No, 



Date of 

 Hatching 



Date of 

 Fiist 

 Moult 



Date of 

 Second 

 Moult 



Date of 

 Third 

 Moult 



Date of 

 Fourth 

 Moult 



Date of 

 Fifth 

 Moult 



Length of 

 Larval 

 Stage 



Date of 



emer- 

 gence of 

 Adult 



Length 



of 

 Pupal 

 Stage 



June 25 

 June 25 

 June 2.5 



July 2 

 July 2 

 July 2 



July 7 

 July 7 

 July 9 



July 12 

 July 15 

 July 15 



July 17 

 July 20 

 July 20 



July 29 

 July 29 

 July 29 



34 days 

 34 days 

 34 days 



Aug. 19 

 Aug. 19 

 .\ug. 19 



21 days 

 21 days 

 21 days 



Geographical Distribution. 



The Parsnip Webworm is an insect with a very wide distribu- 

 tion, having been recorded from England, Scotland, Ireland, 

 Germany, Sweden, Finland, France and the Eastern United States 

 and Canada. It is very common in the neighborhood of Truro, 

 and has been sent to the Agricultural College from parts of Hants 

 and King's Counties, as well as from New Brunswick, 



