140 COLEOPTERA. 



color. They are called oil-beetles in England, on account 

 of the yellowish liquid which oozes from their joints in large 

 drops when they are handled. Their head is large, heart- 

 shaped, and bent down, as in the other blistering beetles. 

 Their thorax is narrowed behind, and very small in pro- 

 portion to the rest of the body. The latter is egg-shaped, 

 pointed behind, and so enormously large that it drags on 

 the ground when the beetle attempts to walk. The wings 

 are wanting, and of course these insects are unable to fly, 

 although they have a pair of very short oval wing-covers, 

 which overlap on their inner edges, and do not cover more 

 than one third of the abdomen. These beetles eat the leaves 

 of various kinds of buttercups. 



Our common species is the Meloe angusticollis of Say, or 

 narrow-necked oil-beetle. (Fig. Qo repre- 

 sents the female, and the antenna of the 

 male at her left.) It is of a dark indigo- 

 blue color ; the thorax is very narrow, and 

 the antennae of the male are curiously 

 twisted and knotted in the middle. It 

 measures from eight tenths of an inch to 

 one inch in length. It is very common 

 on buttercups in the autumn, and I have 

 also found it eating the leaves of potato- 

 vines. 

 The foregoing insects are but a small number of those, 

 belonging to the order Coleoptera, which are injurious to 

 vegetation. Those only have been selected that are the 

 most remarkable for their ravages, or would best serve to 

 illustrate the families and genera to which they belong. The 

 orders Orthoptera, Hemiptera, Lepidoptera, Hymenoptera, 

 and Diptera remain to be treated in the same way, in 

 carrying out the plan upon wfyich this treatise has been 

 begun, and to which it is limited. 



