CLERT AND NECROBI^. 119 



are not numerous, and most of them are by no means 

 common ; their larvse live for the most part in old trees 

 and rotten stumps, where they wage continual war 

 with the larvse of wood- eating Beetles, some of which 

 are their near relations. These are not the only situa- 

 tions, however, in which these larvse are to be met with, 

 for two of our British species {Clerus apiarius and C. 

 alvearius) pass their preparatory state in the nests of 

 Bees, where they find an abundant supply of food in 

 the grubs of those industrious insects. One of these 

 species selects the common Hive Bee for its attacks, 

 whilst the second finds its way into the nests of the 

 Mason Bees. 



A few species nearly allied to these, of small size, 

 but adorned with metallic colours, are remarkable for 

 feeding upon dead animal substances, especially dried 

 skins, or the minute portions of nutriment which can 

 be picked up amongst old bones. These insects belong 

 principally to the genus Necrobia, and one of them, 

 the Necrobia ruficollis, a little blue insect, with the 

 prothorax, the legs, and the base of the elytra red, 

 must ever be regarded with interest by the entomo- 

 logist, from its discovery having been the means of 

 saving the life of one of the most distinguished of 

 French naturalists, Latreille. In the terrible days of 

 the first revolution, he was condemned to " depor- 

 tation^^ to Cayenne, and whilst lying in prison awaiting 

 the execution of his sentence, he one day observed 

 crawling along the wall a specimen of this little 

 Beetle, with which it appears he was not previously 

 acquainted. He immediately pounced upon it with 

 aU the avidity of a young and ardent entomologist, 

 impaled it upon a pin, stuck this into a cork, and 

 contemplated his prize with great satisfaction. A 



