COLLECTKI) OBSERVATIONS ON BRITISH SAWFLIKS. 151 



I have named the group Biophaga, or life-eaters, because I 

 thoiii^hi that name more triuhful, descriptive, and emphatic, 

 than those liitherto employed, — EntotHophaga, Tftopliagn, Pn- 

 rasifa, Ennirora, Pupivorn, Pupoplunja, &c. The Eratiiidce, 

 Ic/uieumonii/(B, ClnilcididcB, and Pt oclro/rupida', are gene- 

 rally esteen)ed the principal ramilies of this order. This is a 

 much n)ore extensive group than is generally supposed. We 

 are too apt to regard Ichneumons as a large tribe of insects 

 associated from their propensity to live parasitically on the 

 caterpillars of butterflies and moths; but this scarcely gives 

 a sufficiently comprehensive idea of the f)henomena. Prof. 

 Westwood, in that vast repertory of entomological fticts, — 

 which requires an index, — ' Introduction to the Modern 

 Classification of Insects,' has collected from a variety 

 of autlientic sources a vast amount of information which 

 widely extends our views of tiiese Biophagans, and shows 

 that scarcely an insect is secure from their attack. I will 

 enumerate a tew of these instances. 



Octopoda. — Several spiders are subject to this plague : the 

 beautifully silk-like egg-nests of many spiders are attacked in 

 this way, and the eggs thus prevented from coming to 

 maturity. Indeed one species of Biophagan is so well known 

 for its ravages on the spider-world that it has received the 

 name of Ichneumon aranenrum.* 



Hexapoda. — In Lepidoptera the liability to parasites is 

 the rule, its absence the exception. In Diptera I have 

 observed the frequent occurrence of hyperparasitism, that is 

 when the fly has deposited its egg on or in the larva of a 

 Lepidopteron : the larva jjroceedin^- from that egg has 

 become the prey of a Biophagan, and thus the original life 

 has been forfeited ; the life of the dipterous destroyer 

 has also been forfeited; and the destroyer of the destroyer, 

 or the hyperparasite, has been the only life to escape. 

 As an example I may state the common woolly-bear, 

 the larva of Chelonia caja, feeds a host of these Biophagans, 

 not only direct parasites, or parasites which not only 

 fulfil their murderous mission on the woolly-bear itself, 

 but which nourished with their own living flesh hundreds of 

 minute Biophagans; so that the bear and its parasites alike 

 perisl) under the terrible infliction of these almost invisible 

 mtu-derers. Some even go farther than this: they pierce the 

 eggs of Lepidoptera with their ovipositor, and fill these eggs 

 with their ravenous progeny. In a word, this parasitism is so 

 * Ichneumon aranedntm. Kourc, is Pezomachus zonatus, Forst. 



