108 INSECTS INJURIOUS TO VEGETATION. 



June, having probably survived the winter in some place of 

 .shelter and concealment, and their larvae in a week or two 

 afterwards. The larvae are broad oval, flattened, dark-colored 

 grubs, with a kind of fringe, composed of stiti' prickles, around 

 the thin edges of the body, and a long forked tail. This fork 

 serves to hold the excrement when voided ; and a mass of it 

 half as large as the body of the insect is often thus accumu- 

 lated. The tail, with the loaded fork, is turned over the back, 

 and thus protects the insect from the sun, and probably also 

 from its enemies. The first broods of larvae arrive at their 

 growth and change to pupae early in July, fixing themselves 

 firmly by the hinder part of their bodies to the leaves, when 

 this change is about to take place. The pupa remains fastened 

 to the cast-skin of the larva. It is broad oval, fringed, at the 

 sides, and around the fore part of the broad thorax, with large 

 prickles. Soon afterwards the beetles come forth, and lay 

 their eggs for a second brood of grubs, which, in turn, are 

 changed to beetles in the course of the autumn. In June, 

 1824, the late Mr. John Lowell sent me specimens of this little 

 beetle, which he found to be injurious to the sweet potato-vine, 

 by eating large holes through the leaves. This beetle is very 

 broad oval in shape, and about one fifth of an inch in length. 

 When living it has the power of changing its hues, at one 

 time appearing only of a dull yellow color, and at other times 

 shining with the splendor of polished brass or gold, tinged 

 sometimes also with the variable tints of pearl. The body of 

 the insect is blackish beneath, and the legs are dull yellow. 

 It loses its brilliancy after death. The wing-covers, the parts 

 which exhibit the change of color, are lined beneath with an 

 orange-colored paint, which seems to be filled with little ves- 

 sels; and these are probably the source of the changeable 

 brilliancy of the insect. 



The Chrysomelians (Crysomei.ad.e) compose an extensive 

 tribe of leaf-eating beetles, formerly included in the old genus 

 Chrysomcla. The meaning of this word is golden beetle, and 

 many of the insects, to which it was applied by Linnaeus, are 

 of brilliant and metallic colors. They differ, however, so much 

 in their essential characters, their forms, and their habits, that 



