VIOLET NEPHELODES: LARVAL HABITS AND CHANGES. 109 



perhaps three hundred species, each needing special investigation, 

 and many showing habits differing so greatly from one another, that 

 very different methods of treatment are required for their destruction, 

 or for the prevention of their injuries. 



In my own experience with the larvne of jV. violans, they developed 

 no cut-worm habits, as they were fed in darkness under cover with 

 cut grass furnished them. Prof. French observed them in an open 

 rearing box and found them to display the same habits witli the larvae 

 of the genus Agrotis, feeding mostly at night and keeping con- 

 cealed during the day, either in the ground or under the loose material 

 upon it. They were sluggish in their movements, except when dis- 

 turbed, when they were quite active. In Illinois (see p. 104), the larvse 

 entered their pupal state m June; in Missouri, the larvae had matured 

 and buried for pupation previous to May 28th; in New York, the earliest 

 matured June 1st and the latest about the 20th, giving for the aver- 

 age time, June 10th. On July 16th one was found to have pupated 

 — how long previously is not known. The larvae evidentl}^, after 

 burying in the ground, remain unchanged for a longer time than most 

 of the NoctuidcB. Thus Prof. Kiley found examples unchanged about 

 a month after they had entered the earth, but it is possible that these 

 may have been diseased or parasitized. It is probable that the inter- 

 val between maturity and pupation does not exceed a month, and is 

 less than one-half that which has been observed in its late associate, 

 Crambus viilgivagellus. 



They continue a long time in their pupal state — the moth not ap- 

 pearing until the end of summer, leaving no time for a second brood. 

 Prof. French gives the species a pupation of between two and one- 

 half and three months in length, but from other observations, it ap- 

 pears as if his statement of " they went into the chrysalis state in 

 June," might properly be amended so as to read^ "they entered the 

 ground for their pupation in June," which would permit the period as 

 above given to be shortened a month. 



Parasitic Attack. 

 The larvae appear to be very subject to parasitic attack. Those that 

 I attempted to rear gave me quite a number of dipterous puparia, of 

 which I have failed to secure the fly, although some of them have 

 emerged. The puparium is quite small, measuring but 0.22 of an inch 

 in length, and indicates a species smaller than any of the 

 Tachina flies known to me. The larva3 must have been parasitized 

 previous to their final moltings, as none of the egg-shells were ob- 

 served upon them. A large hymenopterous larva which escaped from 

 one of the caterpillars, died without forming its cocoon. Prof. Eilev 



