350 NATURAL HISTORY OF ARTHROPODS. 



pairing lias been often obscrvoil. The larv;L' are liatehed in tlie body-cavity; the 

 Stylopidse are consequently vivij)arous. These liexapodous larvie, whieh are very 

 active and have eyes, escape by a dorsal opcnini;- from their mother, and, running 

 about on the female bees, are transported to the nest, v.here they quickly bore into 

 and bury themselves in bee-larvse. Onee inside a bee-larva, the larva 

 of the 8tylo2)s moults in about a week, and appears as a footless grub 

 which feeds upon the fatty portions of the bee-larva. When the bee- 

 larva pupates, its parasite pupates within it. In beeomiiig an imago, the 

 female Styloj^s only bores out through the end of her own pupal skin. 



Fig. 393. — A'oios and through one of the soft folds of the abdomen of the bee, protnidino- 



rossl, female. , , , t , , ,• , , , '^ 



lier head and thorax between two segments oi her liost, but never 



leaving her ]nii)al skin. The males leave the pujial skins, search out females, pair, and 



die, usually in a few hours. Each female is supposed to bear about two thousand 



young larva', nmny of which, on account of their strange mode of life, die without 



finding a suitable place for further development. 



There are but few genera and species of Stylopida>, among which the folloAving 

 genera are j)erha] IS best known, — A'ewo^, with four-jointed antennas and four-jointed 

 tarsi; Stylop.% with six-jointed antcnniT and four-jointed tarsi; and Hi(lictophar/HS, 

 with seven-jointed antennae and three-jointed tarsi. 



Westwood has described a pupa, which he regards as belonging to the Stylopidse 

 and which was found in the abdomen of a hemipteron, under the name of Colacina 

 ihsidkitor ; and the same author has also described a species, imder tlie generic name 

 Mi/rmecolu.)\ which is ])arasitic on ants in Ceylon. 



The RiiiPiPHORiD.E, a family containing only aliout a hundred descril)ed species, 

 includes insects, like so many other heteronierous Coleoptera, remarkable both for 

 abnormal adult structure and for parasitical earlier stages. The larv;e of some are 

 parasitic on lIymenD]itera, of others on Ortho]itera. The beetles are all comparatively 

 small and generally we<lge-shaiied, the anterior ]iortion of the prothorax and the 

 posterior portion of the abdomen usually diminishing gradualh- in size. The head is 

 vertical, and has large eyes; the mouth-parts are well-develo])ed, and the antennre 

 liave usually ten, in some females eleven joints, and are pectinate or flabellate in the 

 males, and often serrate in the females. The elytra are usually shorter than the 

 abdomen, often acutely pointed behind and dehiscent, sometimes very minute; a 

 few females resemble larvre, and want both wings and elytra. The beetles inhabit 

 flowers. 



Some discussion has arisen as to the actual food and moile of life of the larvfe of 

 Rhipiphorida^ in wasps' nests, but the following brief abstract of statements made by 

 Mr. A. Chapman in an account of the life history of H/upiphorus (Metcecus) paradoxus, 

 a common European species which develops in the nests of Vesjm germanica and 

 V. vulgaris, are probably the facts of its mode of life. The female beetle probably 

 lays its eggs outside the wasps' nests; the young larva, which has ocelli and is not 

 unlike the triungulin of the Meloida^ comes into the nest, possibly without help, and 

 enters the cell of a wasp-larva. Before the cell of the wasp-larva is closed up the 

 Hhipiphori/s-lnrvn liores in lietween the second and third dorsal rings of the wasp-larva. 

 Later the I^/iiptp/iorxs-lnrya, after feeding a while in the wasp-larva, breaks out through 

 the fourth ring of its host, moidts immediately, and becomes a grub with poorly 

 developed legs. The ]i;n-asitio larva now fastens itself firmly upon the fourth ring 

 of the wasp-larva, where it later moults again ; soon after this moult the ])arasite has 



