COLEOPTERA. 35 



this destruction, eight hundred eggs, at least, were prevented from 

 becoming matured. During the time of their prevalence, rose- 

 bugs are sometimes found in immense numbers on the flowers of 

 the common white-weed, or ox-eye daisy, {Chrysanthemum leu- 

 canthemum) , a worthless plant, which has come to us from Europe, 

 and has been suffered to overrun our pastures, and encroach on 

 our mowing lands. In certain cases it may become expedient 

 rapidly to mow down the infested white-weed in dry pastures, and 

 consume it, with the sluggish rose-bugs, on the spot. 



Our insect-eating birds undoubtedly devour many of these 

 insects, and deserve to be cherished and protected for their ser- 

 vices. Rose-bugs are also eaten greedily by domesticated fowls ; 

 and when they become exhausted and fall to the ground, or when 

 they are about to lay their eggs, they are destroyed by moles, 

 insects, and other animals, which lie in wait to seize them. Dr. 

 Green informs us, that a species of dragon-fly, or devil's needle 

 devours them. He also says that an insect which he calls the 

 enemy of the cut-worm, probably the larva of a Carabus or pre- 

 daceous ground-beetle, preys on the grubs of the common dor- 

 bug. In France the golden ground-beetle (Carabus auratus) 

 devours the female dor or chafer at the moment when she is 

 about to deposit her eggs. I have taken one specimen of this 

 fine ground-beetle in Massachusetts, and we have several other 

 kinds, equally predaceous, which probably contribute to check 

 the increase of our native Melolonthians. 



There are several more tree-beetles in Massachusetts, which 

 are injurious to vegetation ; but a mere description of them, with- 

 out an account of their previous history, which is not yet fully 

 known, would be of little use to the cultivator of the soil. 



Very few of the flower-beetles are decidedly injurious to vege- 

 tation. Some of them are said to eat leaves ; but the greater 

 number live on the pollen and the honey of flowers, or upon the 

 sap that oozes from the wounds of plants. In the infant or grub 

 state most of them eat only the crumbled substance of decayed 

 roots and stumps ; a few live in the wounds of trees, and by their 

 depredations prevent them from healing, and accelerate the decay 

 of the trunk. The flower-beetles belong chiefly to a group called 

 Cetoniad.e, or Cetonians. They are easily distinguished from 



