THE CHRYSOMELIANS. 123 



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 ex- 

 hibit the change of color, are lined beneath with an orange- 

 colored paint, which seems to be filled with little vessels ; 

 and these are probably the source of the changeable bril- 

 liancy of the insect. 



The Chrysomelians (CHRYSOMELAD^E) compose an exten- 

 sive tribe of leaf-eating beetles, formerly included in the 

 old genus CJtrysomela. 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 they are now very properly distributed 

 into four separate groups or families. The first of these, 

 called GALERUCAD.E, or Galerucians, consists mostly of dull- 

 colored beetles ; having an oblong oval, slightly convex body ; 

 a short, and rather narrow, and uneven thorax ; slender 

 antenna?, more than half the length of the body, and im- 

 planted close together on the forehead ; slender legs, which are 

 nearly equal in size ; and claws split at the end. They fly 

 mostly by day, and are by nature either very timid or very 

 cunning, for, when we attempt to take hold of them, they 

 draw up their legs, and fall to the ground. They sometimes 

 do great injury to plants, eating large holes in the leaves, or 

 consuming entirely those that are young and tender. The 

 larvae are rather short cylindrical grubs, generally of a black- 

 ish color, and are provided with six legs. They live and 

 feed together in swarms, and sometimes appear in very great 



