COLEOPTERA 217 



If the beetle is imprisoned in a closed vessel, the odour soon 

 becomes strong and unpleasant. The devil's coach-horse 

 feeds upon small insects of all kinds, and has the sharp, 

 pointed jaws of a carnivorous beetle. In this and other rove- 

 beetles, probably so called because they are often found stray- 

 ing in an apparently aimless fashion, like creatures that have 

 no home, the short elytra render it possible to erect the tail, 

 which no ordinary beetle with long and rigid elytra can do. 

 Though the elytra of rove-beetles are short, they meet along 

 the back in a straight suture. The wings, when extended, are 

 of tawny colour, and ample size. The devil's coach-horse, 

 like most other rove-beetles, can fly very well. When it 

 alights, the wings are crumpled into a surprisingly small space 

 and completely concealed beneath the short elytra. The egg 

 of the devil's coach-horse is reputed to be the largest laid by 

 any British insect; it is about 2 mm. long, and 1.3 mm. 

 broad. The larva is subterranean, hunting for small insects 

 and worms in holes and crevices, so that it is rarely seen. It 

 resembles the adult beetle in its long, narrow body, its pierc- 

 ing jaws, and its active, predatory habits. The legs are rather 

 long for a beetle-larva, though not nearly as long as those of 

 the adult, the head is broad and fiat, the general colour 

 yellow, but the head dark and the prothorax reddish ; the 

 upper surface of the body is protected by firm shields, and a 

 pair of slender, antenna-like appendages (cerci) stick out from 

 the last segment. Rove-beetles are particularly difficult to 

 rear, and not very much is known of their life-history. In 

 spring or early summer the larva makes for itself a cell in the 

 earth, and changes to a straw-coloured pupa, which is loosely 

 invested by a thin pupal skin. The pupa is particularly soft, 

 wanting all the defences of the larva and imago. When the 

 beetle first emerges it is pale, but soon darkens on exposure 

 to light and air. The pupal stage lasts for a little more than a 

 fortnight. Most rove-beetles are similar to the devil's coach- 

 horse in form and habits, but a few are vegetable-feeders. 

 Some burrow in the banks of streams, or in the sand of the 

 sea-shore, and several species are found only in ants' nests. 



Family Coccinellidse (lady-birds). Hemispherical, or nearly 

 so. Tarsus apparently three-jointed. See Lesson g. 



The family Dermestidae includes a number of small clavi- 

 corn beetles, with distinct 3-jointed club on the antenna. 



