90 



SECOND REPORT OF THE STATE ENTOMOLOGIST. 



Speyer : in Stett. Entomolog. Zeit. for 1875, pp. IGo, 16(3 (compared with P. nt). 

 LiNTNER : in Colvin's 7th Kept. Surv. Adirou. Reg. N. Y., 1880, p. 399 (as P. ni, 



visiting flowers in 111.); in Count. Gent., xlvi, 1881, p. 711 (general notice); 



1st Rept. Ins. N. Y., 1883, pp. 65, 156 (remedy and parasite). 

 Howard : in Bull. No. 3, Div. of Entomol.— Dept. Agricul., 1883, p. 20 (effects of 



pyrethrum on larvae). 



The increasing destructiveness of this insect within the past few years 

 has brought it prominently into notice, and in response to the many re- 

 quests made for information in regard to it, its natural history has been 

 ascertained and published, together with the means by which the exces- 

 sive injuries from it, threatened, may be largely averted. 



Examples of the larvse, pupae and the moths were received from 

 Dover, N. J., during the latter part of October, with the statement that 

 they had been for some time past, and still continued to be, very de- 

 structive to cabbages and Swede turnips, defying the remedies with 

 which the larvae of the cabbage butterfly, Pieris rupee, had been suc- 

 cessfully combatted. The moths had been observed depositing eggs 

 upon the cabbage soon after sunset. It was desired to know if they 

 were an old or a new enemy, and if it was probable that they would 

 continue to be formidable, or were they developed in their present num- 

 bers by the recent heat and drouth. 



Description. 



Larva. — The caterpillar, shown at a in Fig. 15, is of a pale-green 

 color, delicately lined in white, with some small white spots, each 

 of which bears a short hair, usually blackish. The head is small, 

 flattened and shining. The body is slender, deeply constricted 

 at the joints, gradually increasing in size from the head to the 



eleventh segment, where it 

 is rapidly contracted and 

 slopes abruptly to the pair 

 of contiguous anal prolegs : 

 besides these, there are two 

 other pairs of prolegs, and 

 the three pairs of true legs. 

 Its length at maturity is 

 nearly one inch and a quar- 

 ter. 



The method of walking 

 of these caterpillars is rather 



?f*v\ a ) ^^'. "^^v^ unusual among the Nodui- 



^^^ dee, in that they loop the 



Fig. 15.— The Cabbage Plusia, PmsiA brassice: a, the larva; 1 J oft^r tVi/^ mnnnpr nf 

 6, the pupa within the cocoon ; c.Uie male moth. DOQy alter ine manner Ui 



