94 



THE CANADIAN ENTOMOLOGIST. 



THE LIFE HISTORY OF RIVULA PROPINQUALIS, GN. 



BY E. PORTER FELT, B. S., FORT PLAIN, N. Y. 



This rather common moth seems to have attracted little attention, 

 though the larvae are voracious feeders. The moths may be seen flying 

 over grass lands in the afternoon and early evening during June, July 

 and August. They are attiacted to lights but very little, only a few being 

 taken in the trap-lanterns at* Ithaca, N. Y., in 1889. 



The moths deposit their eggs singly, or in scattered clusters of five or 

 six. The eggs are a pale straw colour, and are firmly attached to blades 

 of grass. This insect does not appear to be very prolific : out of seven or 

 eight females under observation, none laid over fifteen or twenty eggs and 

 most of them laid only eight or ten. 



The eggs hatch in about five days. The larva? escape from the egg 

 by eating nearly around the upper surface of the shell and pushing up the 

 lid thus formed. (Fig. 7.) 



The remains of the shell are not molested- 

 When first hatched the larvae are a pale yellowish 

 colour and with long fuzzy hairs on the back ; the 

 hairs are longer at the extremities and incline well 

 over the head. The young larvae begin feeding 

 at once and soon they are a bright green colour. 

 When not feeding the larvae remain quietly upon 

 the surface of the leaf. In this position they har- 

 monize so well with their surroundings that it is 

 difficult to detect them, even when in plain sight. 

 Frequently the best way to find them is to look 

 for injuries to the grass. When very young the 

 Fig. 7.— Latera: and top view larv?e fccd upou tlic Upper surfacc of the leaf, eat. 



of egg; the latter showing . i ,i r. I r .1 i r H7i 



the micropyie and the lid mg Only the soit parenchyma of the leaf. When 



that the larva forms as it , , 1 i i ti i 



makesits way outoftheegg. about two wccKs old they greedily devour the 



reat y en argec . wholc leaf. Bcsides eating considerable, the larvae 



also waste much by cutting leaves off as they feed. The larvse rarely 



move except in search of food unless disturbed, when they usually drop 



to the ground. 



Larvae coming from eggs laid in August moult three times before hiber- 

 nating. When cold weather approaches the larvae crawl down near the 



*The work upon which this paper is based was done at the Insectary of Cornell- 

 University. 



