336 NATURAL HISTORY OF ARTHROPODS. 



finely spotted with cream-white :iiiil witli hl:ick. Tliis heetle is found in species of 

 fungus whicli grow tipon trunks of dead trees. 



Larvae of species of Urac/ii/Uast/s, another aiithrihid genus, are parasitic in the 

 females of different kinds of Cocci<l;e, where thej- eat the eggs of the scale-insects. 

 This is an exceptional nioile of life for weevil larva' ; the majority of thein feed upon 

 vegetable matter. 



The Brexthid^e are very elongated weevils, probably the most elongated, propor- 

 tionately, of all beetles Hrenthus unchordgo., of tropical America as far north as 

 Florida, is about 1.40 inches long and only 0.1'J of an inch wide at its broadest part. 

 Still more pecvdiar than their extreme attenuation is the secondary sexual characters 

 of their mouth-p;n-ts to accord with their functions. In Eupnalis, which differs from 

 Jirenthus in having a convex thorax without grooves, the female has a prolonged 

 I^roboscis, with the mandibles at its tip, as is common among weevils; with this 

 proboscis she bores holes into the bark of the trees wliich are to furnish food for 

 the larv£e, and in each hole she dejiosits an egg. The male, having no such work to 

 perform, has no proboscis, but is provided with strong, curved mandibles of the 

 ordinary type found in beetles. The males have comljats for the possession of the 

 females; and, although they cannot injure one another on account of their hard chili- 

 nous shells, .sooner or later one of the combatants withdraws, tired of the liattle, leaving 

 the other in possession of the female. While tlie female is occu])ied in lioring a hole 

 for an egg, an operation which takes aliout a day, the male ^\larlls her and strives to 

 drive away any other males that apjiroach. Mr. A. K. Wallace says of the Brentliidne, 

 that it is interesting, " as bearing on the question of sexual selection, that in this case, 

 as in the stag-beetles, where the unties fight together, they should be not onlv lietter 

 armed, but also much larger than the females." 



EupsaHs imntita\ii([\iiiYi\}-oXQi\ throughout the eastern United States 

 and Canada, although most of the Brenthidas are confined to the tropics. 

 It is shining mahoganj'-brown, with fine yellow spots on the elytra, and 

 is very variable in size, males sometimes measuring over 0.75 of an inch 

 long, while females are now and then found that are not over 0.25 of 

 an inch long. Tiie elongated larva of E. •tniuKta, which lias been 

 Fig. nw. — Eup- described Ijy Dr. C. V. IJiley, inhabits decaying oak wood, around 



satis minuta. i • i 4.1 i *-! i. 



which the beetles are not rare. 



The ScoLVTiD.E are small Ijcetles, some of them almost microscopic, all ha\ing a 

 similar general aspect and a nearly cylindrical form, and are, for the most ])art, of a 

 brown color. The head is usually short, and imbedded in the anterior end of the 

 protliorax ; tlie proboscis is .short, often not ajiparent ; the antenn;e are small, genicu- 

 late, clubbed; the tibia' .are usually serrate; the horizontal pygidium is undivided in 

 both sexes, and is surroundeil at its edge l)y the elytra. Both the mature beetles and 

 their larva3 bore in plants, usually trees, on which they feed, often between the bark 

 and wood, — more accurately speaking in the liber, — and their channels, revealed by 

 pulling off the bark, exhibit many curious forms characteristic of the species or genei-a 

 of SeolytidjE to which they jiertain. These beetles are especially destructive to Coni- 

 fene ; some species attack other trees, and a few injure herbaceous plants. 



The peculiar forms taken by the mines of these beetles in wood and bai-k are 

 dependent upon the mode of oviposition of the diffei-ent species. The malrs form 

 chambers (" Rammelkammer " of K. Lindemann) in the bark, in which they await the 

 females. After pairing, the females enlarge and prolong this cojnilation-chamber, 



