Observations on Insects affecting the Turnij) Crops. 313 



it may arise from their crossing with P. KapcB, for hybrids un- 

 doubtedly exist amongst insects. The males are nearly f of an 

 inch long, and scarcely expand 2 inches ; the females are a little 

 larger. 



The eggs of this species are also laid singly on the under side 

 of the leaves of cabbages, turnips^ and other Cruciferae ; they are 

 long, cylindric, of the form of a sugar-loaf, channelled^ striated 

 transversely, and whitish (fig. 18) : the caterpillars are about the 

 size of the foregoing ; they are of a delicate green colour, densely 

 clothed with velvety hairs, the spiracles or breathing pores down 

 the sides being reddish-yellow (fig. 19) ; and when lying stretched 

 out on the leaves, as they do by day, they are scarcely visible to 

 the eye. The chrysalis is suspended like the others ; it is of a 

 pale greenish- white, or yellow and freckled, with the beak and 

 points brown (fig. 20). 



There are two broods of this Butterfly in a year, one in April 

 or May and another in July or August ; the caterpillars are most 

 injurious in gardens, where last year they not only fed upon 

 the turnip-leaves, but did great mischief to the cabbages, es- 

 pecially in September, eating the central leaves, like the cater- 

 pillar of the Cabbage-Moth, Noctua Brassicce, and I killed 

 several as late as the 22nd of September. I have found the pupae 

 of this species with a largish hole on one side, from which had 

 issued a parasitic Ichneumon ; and I bred an incredible number, 

 considering their size, of males and females of this fly in July or 

 August from one pupa; it is called by Gravenhorst* 



8. Hemiteles melanarius : ■]- the 7nale is entirely black and 

 punctured ; the abdomen is roughly punctured, the margins of the 

 segments and. the apex are smooth and shining, the two slender 

 horns are scarcely so long as the animal : the wings are beautifully 

 iridescent, the nervures and stigma pitchy, the areolet is open 

 outside ; legs black ; the apex of four anterior thighs and their 

 tibiae are tawny, the feet are brownish, but the basal half of the 

 hinder tibiae alone is tawny : length 2 lines, expanse near 4 lines : 

 the female differs so materially that no one would suppose it was 

 the legitimate partner of the foregoing male : it is blacky but the 

 abdomen is red, excepting the basal segment and the apex ; the 

 ovipositor is exserted, and is half the length of the abdomen : the 

 thighs and shanks are red, the apex of the hinder tibiae and all 

 the tarsi are brown : length, including the ovipositor, nearly 

 3J lines, expanse almost 5 lines. 



Where any of the White Butterfly caterpillars abound, there 

 are several methods of reducing their numbers and checking their 

 increase ; the best is to look in the v/inter for the chrysalides, 



* IclineuraonologiaEuropsDa, vol. ii. p. 790, No. 233. 

 t Cuvtis's Guide, Gen. 503, No. 233. 

 VOL. III. Y 



