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Show 240 DARWINISM CHAP. fa.mnics or orders. One creature seems disgui::;cd in order to be made like n.nothcr; hence the terms "mimic" and mimicry, which imply no voluntn.ry action on the part of the imitato r. It has long been known that such resemblances do occnr, as, for example, the clcn.r-wingcd moths of the families f 'csiidm ancl .lEgcriidre, many of which resemble bees, wasps, ichnenmons, or sn.w-flies, and have received names expressive of the 1·c· semblance; and the para itic flies (Volucclln,) which clos •ly resemble bees, on who. c hrvre the hrvm of tho fli es fe ed. Tho grcn.t bulk of such ca. es remained, however, 1mrrot i<'ncl, and tho snhjcct was looked upon ns one of tho inexplic:ll •k curiosities of n:tturc, till Mr. 13atcs stmli d tho phcnomC' non among the butterflies of tho Amazon, n.nd, on his l'ctnm h o~n<', gave the first rational explanation of it. 1 Tho facts arc, hr ·it•fl r, these. Everywhere in that fertile r ccrion for th c ntonr ol ogi~t tho brilliantly coloured Hcliconidro abound, with all the cl.raracteristics which I have already referred to when dcscr ihi 1 w th om as 1'1 1 us t ra t1' vc of " warnm. g co 1o mtw. n. " 13ut nlOJwb with them other butterflies wore occasionally captnrcrl ·whi<'l ~ though often mistaken for them, on account of t heir cl ns~ resemblance in form, colour, and modo of 11i[;lrt, were fon11 cl on examination to belong to a very di tinct family, the Pierida~. Mr. Bates notices fifteen distinct species of J>icri<lrC' hclon<•irw . ' b b to the genera Lcptahs nnd Euterpe, each of which clo. clyimi t:ttcs some one sp cies of IIeliconidre, inhabiting tho same r (•gion <1n cl frequenting the same localities. It mu t be r cmcmhcrecl that tho two families arc altogether eli tinct in stmctnrc. The larvm of tho Heliconidro arc tubercled or spi11 cd, tho pnpn1 F>ll spcndcd head downwards, and tho imago has impel'fecL fon)lcgs in tho male j while tho larvre of the Pi eridm arc smoot h, tho pupro arc suspended with a brace to keep tho hea.cl erect, and the forefeet arc fully developed in hoth . exes. These differences arc as large and as important as t hose lJetwccn pig. and sheep, or bctw en swallows and Rparrows j while En:rli sh entomologists will best understand the c:t. c hy supposing ' that a species of Pieris in this country was colourecl nrHl slmpcd like a small tortoise-shell, while another pocies on tho Continent was equally like a Cambcrwoll beauty-so like in both 1 See Tm,nsactions of tlte Linllcan, uciety, vol. xxiii. pp. 4.% -CG G, coloured plates. IX WARNING COLORATION AND MIMICRY 241 cases as to be mistaken when on the wing, and tho difT'ercnce only to he detected by close examination. As. a~ cxa~1plc of the resemblance woodcuts arc aiven of one pa1r m wh1ch the colours are sim~le, being olive~ yellow, and black, while the Fw. 23.-Methona psidii (Heliconidre). Leptalis orisc (Pierida>). very distinct neuration of the wings and form of the head a.ncl body can be easily seen. . .. Besides these Pieridro, Mr. Bates found four true Pap1hos., seven Erycinidre, three Castnias (a gcnu.s of day.-fl~in~ moth. ). and fourteen species of diurnal Bombyc1dre, all1m1tatmg some species of Heliconidre which inhabited the sam~ district j and it is to be especially noted that none of these msccts were so abundant as the Heliconidre they resembled, generally they R |