232 INSECTS INJURIOUS TO VEGETATION. 



open and escape from the shells of the chrysalis in the winged or 

 moth state. Under this form this insect was described, in my pa- 

 per in Professor Siliiman's " Journal of Science", by the name 

 of Trochilium * dcnudatum; as the habits of the larva are now as- 

 certained, we may call it the ash-tree Trochilium. Its general 

 color is brown ; the edges of the collar and of the abdominal 

 rings, the shins, the feet, and the under-side of the antennae are 

 yellowish. The hind-wings are transparent ; the fore-wings are 

 opake and brown, variegated with rust-red ; they have a trans- 

 parent space near the tips, and expand about an inch and a half. 



During the month of August, the squash and other cucurbita- 

 ceous vines are frequently found to die suddenly down to the root. 

 The cause of this premature death is a little borer, which begins 

 its operations near the ground, perforates the stem, and devours 

 the interior. It aftei^wards enters the soil, forms a cocoon of a 

 gummy substance covered with particles of earth, changes to a 

 chrysalis, and comes forth the next summer a winged insect. 

 This is conspicuous for its orange-colored body, spotted with 

 black, and its hind-legs fringed with long orange-colored and 

 black hairs. The hind-wings only are transparent, and the fore- 

 wings expand from one inch to one inch and a half. It deposits 

 its eggs on the vines close to the roots, and may be seen flying 

 about the plants from the tenth of July till the middle of August. 

 This insect, which may be called the squash-vine iEgeria, was 

 first described by me in the year 1 S28, under the name of ^ge- 

 ria Cucurbitre, the trivial name indicating the tribe of plants on 

 which the caterpillar feeds f. 



The pernicious borer, which, during many years past, has 

 proved very destructive to peach-trees throughout the United 

 States, is a species o^ ^geria, named exitiosa, or the destructive, 

 by Mr. Say, who first scientifically described it in the third vol- 

 ume of the " Journal of the Academy of Natural Sciences of 



" The word Trochilium is derived from Trochilus, the scientific name of the 

 humming-bird genus ; and these insects are sometimes called humming-bird 

 moths. 



t See " New England Farmer", Vol. VIII., p. 33 ; my Discourse before the Mas- 

 sachusetts Horticultural Society, in 1832, p. 26; and " Siliiman's Journal", Vol. 

 XXXVI., p. 310. 



