266 Arthropoda. 



when the animal is in the natm-al position, as well as when it is on its back. Tha 

 head is sunk deeply into the prothorax, the antennae are serrate or pectinate. The 

 larvae (Wire-worms) are long, sometimes almost wiry and firmly chitinised, 

 with legs, but without eyes ; the last segment large and varying in foi-m. These 

 Insects are for the most part phytophagous. The Buprestidm (genus Bwprestis 

 and others) are alUed to the Elateridae, which they closely resemble in form, 

 in the relations of the head, and in the serrate antennae ; they difEer, however, 

 amongst other things, in the absence of the springing apparatus. The larvae 

 are whitish, blind, apodous ; the prothorax into which most of the head is sunk, 

 is usually very large and broad, the abdomen naiTow ; they usually live upon 

 wood, as do longicom lai-vae, which they closely resemble. The Buprestidae 

 are specially abundant in the Tropics, where large and beautiful foi-ms are 

 met with ; in temperate countries there are i-elatively few, and they are mostly 

 small. 



7. The Malacodermata are characterised by the unusual softness of the 

 exoskeleton, the eljrtra, for instance, crumpling up when dried. The head is 

 generally more or less hidden beneath the front edge of the broad, shield-shaped 

 prothorax. The elytra fit closely together along the back as usual. The 

 Glow-worms {Lampyrisj , represented in Britain by two species , belong here ; 

 in these the head is covered by the prothorax, the females have neither elytra 

 nor wings, and look like lai-vae; the adtilts of both sexes and the larvae (which 

 feed upon Molluscs) have phosphorescent organs on the ventral side of the 

 abdomen. In the allied genus Telephorus (which is not luminous) the head 

 projects freely; in the summer several species are found on flowers. 



8. The Vesicantia are heteromerous, i.e.. the tarsi of the front 

 and middle legs are five-jointed, those of the hind legs, four- jointed.* The 

 head is constricted posteriorly to foi-m a neck, the prothorax is naiTower than the 

 elytra, which are not so hard as in most Beetles. The claws are cleft ; blistering 

 materials are contained in the body. The ova are laid in holes in the earth ; the 

 newly-hatched larvae possess eyes and well-developed legs, and crawl about 

 on plants, attaching themselves to certain Bees and entering their nests with 

 them ; when the Bee lays an egg the parasite leaves its host and remains in the 

 cell, where it first devours the egg, and then undergoes a metamoi'phosis, becoming 

 a clumsy, blind, short-legged ci-eature, which devours the suppUes intended for the 

 bee-larva. To this group belongs also the Oil-beetle (Meloe), with no hind wings 

 and with short elytra, which do not fit together, but overlap : also the Spanish- 

 f ly (Lytta vesicatoria), a beautiful emerald green beetle, with weU-developed 

 eljrtra and wings: rare in England, whilst Meloe is common. The Meal- 

 worm {Tenebrio molitor), a brown, elongate insect, like the Carabidae, belongs 

 to another family of Heteromera. The larva resembles that of the Elateridae, 

 and is well-known in meal and corn. 



9. Longicorns (Ceramhycidse, genus Cerambyx, etc.) The tarsi are 

 broad, and apparently consist of only fom- joints, the last being short and 

 difficult to see (Beetles with this type of foot are termed tetramerous). 

 They are for the most part large with long heads, long antennae in the 

 males often strikingly developed, and emarginate eyes. The larvae which 

 live in wood, and especially in dead trees, gnawing out Ipng tunnels, are 

 whitish, long and somewhat flattened ; broader in front, without (or with feebly- 

 developed) eyes, vsdth very small legs (or quite apodous). The Leaf-beetles 

 (Chrysomelidx) ai-e apparently very different from the Cerambycidae ; they are, 

 however, closely allied, and possess a tarsus of the same form. The body is 



* The families already mentioned have usually five-jointed tarsi on all the legs, 

 and are termed pentamerous. 



