COLEOPTERA. 113 



net. They should be killed by throwing them into scalding 

 water, for one or two minutes, after which they may be spread 

 out on sheets of paper to dry, and may be made profitable by sell- 

 ing them to the apothecaries for medical use. 



There are some blistering-beetles, belonging to another genus, 

 which seem deserving of a passing notice, not on account of any 

 great injury committed by them, but because they can be used in 

 medicine like the foregoing, and are considered by some natural- 

 ists as forming one of the links connecting the orders Coleoptera 

 and Orthoptera together. These insects belong to the genus 

 Meloe, so named, it is supposed, because they are of a black, or 

 deep blue-black 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 proportion 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 JVIcloe angusticollis of Say, or 

 narrow-necked oil-beetle. 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 butter- 

 cups 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, belong- 

 ing 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, Hemip- 

 tera, Lepidoptera, Hymenoptera, and Diptera, remain to be 

 treated in the same way, in carrying out the plan upon which this 

 treatise has been begun, and to which it is limited. 



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