292 ICHNEUMON BORERS. 



a dwarf or a giant of its family, has a figure of such peculiar 

 cut as to make it easy enough, when acquainted with one, 

 to recognize a hundred of his name. We may know them by 

 their long narrow bodies, so convenient for prying and poking 

 into holes and corners, as well as by their long, flexible, 

 jointed horns, so continually on the vibrate as to have pro- 

 cured for their possessors the appellation of Muscce vibrantes. 

 With these organs l (supposed to combine the uses of feelers 

 and of ears) our pryers are to be seen for ever exploring, 

 both by touch and hearing, the places and the living subjects 

 best suited to receive their eggs. 



Cuckoo-flies is another appellation by which ichneumons 

 are distinguished, because, like the cuckoo, they are accus- 

 tomed, lazily, intrusively, dishonestly, and cruelly, to deposit 

 their eggs in stranger nests sometimes within stranger egg- 

 shells sometimes within the bodies of stranger grubs and 

 caterpillars, either in their infancy or when they have attained 

 their growth. For execution of these her nefarious practices, 

 the female ichneumon is provided with a very conspicuous 

 instrument, tail-like, seeming composed sometimes of one, 

 sometimes of three divergent hairs, but consisting, in fact, 

 of a single ovipositor or borer, with a ' sheath longitudinally 

 divided and opening like a pair of compasses. 



The nicest adaptation marks this curious instrument, which, 

 according to the different species and habits of its possessor, 

 is employed to pierce, sometimes only an exposed egg, some- 

 times the skin of a grub, caterpillar, or chrysalis, and some- 

 times through defences strong and deep, coverings of silk, or 

 wood, or clay ; and, according to these varied requisitions, it is 

 shorter or longer, thinner or thicker, stiffer or more pliant. 



In one large and common ichneumon, 2 easily known by 

 her black body, red legs, and smoke-coloured wings, spotted 

 at the base, this tail-like appendage reaches into inches, some- 



1 Antennae. 3 Pimpla manifestator. 



