THE INSECT WORLD. 



259 



impracticable, any of the arsenites may be employed. The 

 attempt has been made, not without a fair degree of success, to 

 protect tobacco plants by killing off the moths while feeding in 

 the flowers of the "Jimson weed," a few drops of a poisonous 

 solution being placed in the bottom of each flower. It is perhaps 

 questionable whether the results obtained justify the method 

 from a practical stand-point, and the direct application of poison 

 to kill the larvae is, all things considered, the most satisfactory. 



Following the hawk-moths in our lists, but not in the least 

 related to them structurally, are the clear-winged moths belong- 

 ing to the family SesiidcB. They are slender bodied, with quite 

 long antennae, the wings narrow, often without scales, the colors 

 metallic or at least glistening, and usually bright and contrasting. 

 They often resemble and are considered wasps or hornets from 

 their appearance, the more so because it is quite usual for them 

 to have the abdomen banded with yellow. These creatures are 

 the parents of borers that are among the most injurious to culti- 

 vated plants. 



First in the series is the ' ' squash-borer, Melittia ceto. This is 

 readily recognized in the adult stage by the opaque, greenish 

 fore-wings, and by the unusually large, thickened hind legs, 

 tufted with black and orange, giving the insect a characteristic 

 appearance, different from any other common species. It may 

 be found during late spring or early summer hovering about the 

 squash or other cucurbit plants during the day, but in the even- 

 ing and during the night resting exposed upon the leaves. It 

 lays its eggs preferably on the vine just at the surface of the 

 ground, if the soil is light even a little below, but it is by no 

 means confined to this point, and may lay them anywhere, even 

 on a leaf or leaf-stalk. They are brown in color, disk-like, and 

 have a very brittle shell. The larvae when hatched are white or 

 nearly so, with a small brown head, a full complement of legs, 

 and at once bore into the stem of the vine. Preferably they live 

 just at the surface of the ground, really eating very little of the 

 plant, but rather they suck the juices, causing its enfeeblement 

 and ultimate death. When full grown in midsummer the larva 

 goes a short distance underground and forms a very tough, 

 parchment-like cocoon in which it rests until the year following. 

 In spring the pupa, by means of its chisel-like head-case, cuts a 



