LEAF-BEETLES. 



169 



ing- plants they are so curious, and so often mailed as "gold-bugs" 

 to the entomologist, that a few words about them may not be 

 amiss. 



In these beetles the ovate and almost quadrate body is flat- 

 tened below and convex above; the head is nearly or quite con- 

 cealed beneath the prothorax and the margins of the latter and of 

 the elytra are broadly expanded, in some cases forming an almost 

 circular outline, and in this way resembling the shell of a tortoise. 

 This resemblance is heightened in at least one case, (Coptocycla 

 clavata Fab.), by four dark projections of the central dark color 

 of the wing-covers, which marks look like the broad legs of a 

 turtle (Fig. 173). In another case (C. guttata Oliv.), only the 

 front legs of a turtle are painted upon the frontal sides of the 

 elvtra. 



cZ 



Fig. 174-. — Coptocycla bicolor. Fab. — After Riley. 



As already mentioned these beetles, when happy, are of bril- 

 liant colors, sometimes ornamented with black spots or longitudin- 

 al lines. One of our most common species, the Cossida bicolor 

 Fab., (Fig. 174), so destructive to morning-glories and sweet- 

 potatoes, is, during its wedding season, like a drop of burnished 

 gold, which towards night is apt to fade to a peculiar pearly lus- 

 ter. Unfortunately such colors are not "fast," but disappear 

 after the death of the insect. It is even claimed that the bright 

 colors of these insects are dependent upon the emotions of the 

 beetles. 



