240 INSECTS INJURIOUS TO VEGETATION. 



with light and dark brown, glossed with reddish white, and 

 with a pale gold-colored semicolon on the middle of the hinder 

 pair. Expands from 2^ to 2| inches, or more. 



The paly gold character beneath the hind wings has much 

 more nearly the shape of a semicolon than of a note of inter- 

 rogation ; for which reason I have called this the semicolon 

 butterfly, instead of translating the specific name. It first 

 appears in May, and again in August and September, and is 

 frequently seen on the wing, in warm and sunny places, till 

 the middle of October. The caterpillars live on the American 

 elm and lime trees, and also on the hop-vine, and on the latter 

 they sometimes abound to such a degree as totally to destroy 

 the produce of the plant. In the latter part of August the 

 hop-vine caterpillars come to their full growth, and suspend 

 themselves beneath the leaves and stems of the plant, and 

 change to chrysalids. This fact affords a favorable opportunity 

 for destroying the insects in this their stationary and helpless 

 stage, at some loss, however, of the produce of the vines, 

 which, when the insects have become chrysalids, should be cut 

 down, stripped of the fruit that is sufficiently ripened, and then 

 burnt. There is probably an early brood of caterpillars in June 

 or July, but I have not seen any on the hop-vine before 

 August, the former are therefore confined to the elm and other 

 plants, in all probability. The caterpillar is brownish, varie- 

 gated with pale yellow, or pale yellow variegated with brown, 

 with a yellowish line on each side of the body ; the head is 

 rust-red, with two blackish branched spines on the top ; and 

 the spines of the body are pale yellow or brownish and tipj)ed 

 with black. The chrysalis is ashen brown, with the head 

 deeply notched, and surmounted by two conical ears, a long 

 and thin nose-like prominence on the thorax, and eight silvery 

 spots on the back. The chrysalis state usually lasts from 

 eleven to fourteen days; but the later broods are more tardy 

 in their transformations, the butterfly sometimes not appearing 

 in less than twenty-six days after the change to the chrysalis. 

 Great numbers of the chrysalids are annually destroyed by 

 little maggots within them, which, in due time, are transformed 

 to tiny four-winged flies [Pleromalus Vanesscu), which make 



