322 NATURAL HISTORY. 



or on moss. In tropical America a genus named Chelonarium is found differing from the rest of the 

 family by their filiform antennae, concealed in repose in grooves along the breast. These are much 

 less convex than the Byrrhi, and have a naked shining surface. They live on trees. 



The last family of Necrophaga the HISTERID.E are recognisable at once from all their relatives 

 by their general appearance, or facies, although this is subject to wide modifications. The majority are 

 of compact oblong or nearly cubical shape, with solid glossy integuments of deep black or brassy 

 colours, scored above with a few sharp striae, the head being retractile within the prothorax, and the 

 gait much resembling that of a Tortoise. The general air of relationship is retained, although some of 

 the genera are modified into oblong and flattened forms with exserted heads, and others are changed in 

 an opposite direction into tiny cylinders modifications corresponding with the changed mode of life of 

 the species, the ordinary cubical Histeridse living on dead animal and excrementitious substances, and 

 in loose decaying vegetable matters. The oblong and flattened species are restricted to narrow crannies 

 under bark, where they live in company with the equally flattened Cucujidse, and the small cylindrical 

 kinds bore into the trunks of trees. The last-named, belonging chiefly to the genus Trypanceus, when 

 seen at work at a dead tree, resemble little animated gimlets. They are furnished with sharp 

 triangular heads, which are plunged into little holes in the wood, made by the jaws in places where the 

 bark has been stripped off, and twirling their bodies the insects rapidly drill their way into the 

 interior, a stream of fine sawdust meanwhile trickling from the holes. Some of the very large species 

 with projecting mandibles feed on inspissated sap exuding from the crowns and stems of fallen 

 palm-trees. As to the structural characters of the family, the chief distinctive features are the 

 abbreviated and truncated wing-covers, and the short, retractile, elbowed and clubbed antenna;. 

 Histeridse are found in all climates, and are exceedingly numerous in generic and specific forms. 

 About 1,200 species have been described, 



CHAPTER IV. 

 THE LAMELLICORN AND SERRICORN BEETLES. 



PENTAMERA (continued) TRIBE LAMELLICORNIA High Degree of Specialisation of the Tribe Concentration of the Nervous 

 System Larvae and Metamorphosis Horned Species FAMILY LUCANID^;, or STAG BEETLES FAMILY SCARAB^ID.*:, or 

 TRUE LAMELLICORNIA Dung-feeding Scarabaeidae The Sacred Beetle Pill-rolling A Parasitic Species Burrows of 

 Geotrupes Leaf -eating Scarabaeidae Cockchafers Goldsmith Beetles Khinoceros and Elephant Beetles Rose- 

 chafers Goliath Beetles TRIBE SERRICORNIA Peculiar Structure of the Fore and Middle Sternums FAMILY 

 BUPRESTHXE FAMILY ELATERID.E, or CLICK BEETLES Fireflies TRIBE MALACODERMATA Glowworms Object and 

 Cause of their Light FAMILIES CLERID^E, PTINID.E, AND BOSTRICHID^;. 



TRIBE LAMELLICORNIA. 



THIS tribe comprehends all those conspicuous members of the Beetle order known by the names of 

 Scarabgei, Cockchafers, May-bugs, Rosechafers, and so forth, which, by their large size, their 

 great numbers, the singular habits and striking form of many of the species, and the great destruction 

 many of them cause to trees and farm produce, have in all ages attracted popular attention. They 

 are recognisable by the short antennae being terminated by a lamellated club, formed by the three or 

 more apical joints being elongated (on one side only), each into a little plate or " lamella," which are 

 separately movable in the chief group, or Lamellicornia proper, and immovable in the Lucanidae, or 

 Stag-beetles. The parts of the mouth show a high degree of specialisation, in the great development 

 of the solid horny mentum, or chin, and the subordination of the labial or lingual paits, which are 

 more or less hidden within the mouth, behind the front edge of the chin. These characters, taken 

 in conjunction with the consolidation of the abdominal segments, of which, in some genera, the con- 

 necting sutures of the ventral side are even obliterated, and a corresponding concentration of 

 the nervous system, shown by the union at least, in the highly-developed sub-families of the 

 ganglions of the hind body into a single large mass within the thorax, justify the views of 

 those entomologists who have held that this tribe are the most highly organised of all Coleoptera. 

 The legs in all the species are more or less long, and furnished with spines and transverse ridges, the 

 shanks of the fore pair having one or more sti-ong tooth-like projections on their outer edge, 

 indicating fossorial or burrowing habits. The tarsi are always five-jointed. 



