CLASS I. INSECTA: ORDER 1. COLEOPTERA, 



651 



grayish-brown creature, rather more than half an inch lung, and quite destitute of wiugs. The 



male, on the contrary, is active, and 

 flies well ; and the luminosity of the 

 female appears to be intended to at- 

 tract her volatile companion. The 

 light proceeds from the under part of 

 the abdomen and near the tip, and 

 the animal appears to have the pow- 

 er of varying its intensity. If this 

 luminous portion be removed, it re- 

 tains its illuminating property for 

 some time. If the glow-worm be im- 

 mersed in warm water, it emits a bril- 

 liant light ; if placed in cold water, its 

 light is extinguished. 



The larva3 of some species of the 

 genus Clems live parasitically in the 

 nests of bees and wasps, feeding upon 

 their larvae. 



THE GLOW-WORM. 



THB SPANISH FLT. 



THE HETEEOMERA. 



This term is from the Greek heteros, dissimilar, and mera, divisions ; it includes several genera, 

 the spines having four joints in the posterior tarsi, and five in the other four feet. 



THE TRACHELIA. 



The Trachclia are generally active diurnal insects, frequently adorned with gay colors. Their 



bodies are often soft, the elytra flexible, and sometimes much shorter 

 than the abdomen. To this tribe belongs the Blister or Spanish 

 Fly, Lytta vesicatoria, the important medicinal uses of which, under 

 the name of Cantharides, are so well known. These insects are com- 

 mon in the south of Europe, and are especially abundant in Spain, 

 where they are taken in large numbers, and from which source the 

 best are generally obtained. They feed principally upon the ash. 



Many other insects belonging to this tribe, also contain a substance 

 which has the effect of raising blisters when applied to the skin ; and 

 these are employed in their native countries in place of the Lytta vesicatoria. The species of 

 Meloe, several of which are found in Great Britain, possess this property ; Avhich, however, seems 



in all cases to increase in intensity in proportion to 

 the heat of the country in which the insects live. 



Tlie species of Meloe are soft, sluggish beetles, 

 with short elytra and no wings, and may be 

 found crawling about among the grass, in warm, 

 sandy places in the early summer. The young 

 larva?, on first leaving the egg, attach themselves 

 to wild bees, and it is supposed that they are after- 

 ward parasitic upon the bee larva?. In this country 

 the Uj^icauta vittata, often called the Potato Fly, 

 as well as other species, have the power of raising 

 blisters and may be used for this purpose. 



The curious Rijnphorus paradoxus — a small 

 beetle, also belonging to this group — is parasitic in the nests of the common wasp ; and many 

 other species appear to be parasitic in their larva state. One of the most beautiful of the Euro- 



THK PYROCHROA RUBENS. 



