314 TRANSFORMATIONS OF INSECTS. 



solitary bees. Another species selects the hive bee, and lays its 

 eggs in the cells with the larvae of the bees. The larvae of the 

 beetles, when they have destroyed those of the bees in one part 

 of the hive, search out the others, and proceed from cell to cell 

 devouring the inhabitants of each. 



In the engraving on page 313 the nests of the bee are seen 

 in section, and the larva of the beetle is drawn between two adults. 



Another species {Clcrns formicarius) is a little red insect, 

 which is rather common, and its larvae live under the bark of 

 old trees, where they chase and devour many wood-eating in- 

 sects, especially larvae. Others, belonging to the genus Necrobia, 

 feed, both in the perfect and larval state, upon carrion and dead 

 animal matter, such as dried skins and old bones. They are 

 very common in houses, and one species frequents prisons and 

 other gloomy places. Some of the larvae of the genus Anobitim 

 live in old wood, which they eat, and they undergo their meta- 

 morphosis in a small cell, which they form within planks and 

 beams in old furniture, and when they become beetles they eat their 

 way out by drilling small round holes, which every one has seen 

 in old houses. The beetles are nocturnal in their habits, and 

 call each other by striking their mandibles against wood, and 

 they answer each other in the same manner. The blow produces 

 a little tick, and it is repeated at intervals. The beetle being in- 

 visible, superstitious people have a nervous dread of it, and many 

 old women, especially nurses, call it the death tick, and prophesy 

 a fatal issue of the complaints of the sufferers they are watching 

 if the beetle calls its love in this very disagreeable manner. 



Elm trees are very often noticed to be scored beneath the 

 bark by radiating lines, which are arranged in a very regular 

 manner. This is the work of a most destructive beetle, which 

 is called Scolytus destructor. It is worthy of its name, for many 

 large trees and whole forests finally succumb to its attacks. 

 They have small and projecting heads, club-shaped antennae, 

 and very strong mandibles. In the adult form they nibble the 

 bark of trees, and suck the sap, and the females lay their eggs 

 on the trees the sap of which does not circulate very actively. 

 The female penetrates underneath the bark, and screws herself in 

 between it and the woody tissue. She makes a gallery, into 



