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Show 334 DARWINISM CHAP. of colour or marking, often superimposed upon prot~ctiv1e tints, in the importance of easy recog?-ition by many ~mma s of their fellows their parents, or thmr ma.tes. By this need we have been able to account for markings that seem calculated to make the anima.l conspicuous, when the general tints and well-known habits of the whole group demonstrate the need of concealment. Thus also we are able to explain th con tan.t symmetry in the markings of ':ild animals, as well a. the numerous cases in which the conspicuous colours are concealed when at rest and only become visible during rapid motion. In strikinO' contrast to ordinary protective coloration we haYe "warni1~g colours," usually very conspicuous and often brilliant or ga.udy, which serve to indicate that thei 1 r posse~sors are either da.nO'crous or uneata.ble to the usua. enemies of their tribe. This kind of coloration is probably more prevalent than ha.s been hitherto supp?sed, becau_se in ~he case of many tropical animals we are qm_te unacquamted with their special and most dangerous enemies, a.nd ~re also unable to determine whether they are or are not distasteful to those enemies. As a kind of corollary to the " warning colours " we find the extraordinary phenomena. of "mimicry," in whi~h defenceless species obtain protection by being mistaken for those which from any cause, possess immunity from attack Although a' large number of ins_ta~ces of warni~g colour and of mimicry are now recorded, It IS proba~ly still an almost unworked field of research, more especially m .tropical regions and among the inhabi_t~nts of the oce_an. The phenomena of sexual diversities of color~tl?n next engaged our attention, and the reasons why Mr. DarWin s theory of " sexual selection," as regards colour and ornament, co~ld not be accepted were stated at some length, together w1 th the theory of animal coloration and ornament -:re propose to substitute for it. This theory is held to be m harmony with the O'eneral facts of animal coloration, while it entirely dispenses 0 with the very hypothetical an~ inadequate agency of female choice in producing the detailed colours, patterns, and ornaments, which in so many cases distinguish the male sex. If my arguments on this point are soun~, they ~ill dispose also of Mr. Grant Allen's view of the direct actiOn of the XI THE SPECIAL COLOURS OF PLANTS 335 colour sense on the animal intcguments.1 He argues that the colour. of insects and birds reproduce generally the colours of the flowers they frequent or the fruits they eat, and he adduces numerous cases in which flower-haunting insects and fruit-eating birds are gaily coloured. This he supposes to be due to the colour-ta.ste, developed by the constant presence of briuht flowers and fruits, being applied to the selection of each variation towards brilliancy in their mates ; thus in time producing the gorgeous and varied hues they now possess. Mr. Allen maintains that "insects arc bright where briO'ht flowers exist in numbers, and dull where flowers arc rare 0 or inconspicuous ; " and he urges that "we can hardly explain this wide coincidence otherwi. e than by supposing that a taste for colour is produced through the con tant search for food among cntomophilous blossoms, and that this taste has reacted upon its possessors through the action of unconscious sexual selection." The examples Mr. Allen quotes of bright insects being associated with bright flowers seem very forcible, hut are really deceptive or erroneous ; and quite as many cases could be quoted which prove the very opposite. For example, in the dense equatoria.l forests flowers are exceedingly scarce, and there is no comparison with the amount of floral colour to be met with in our temperate meadows, woods, and hillsides. The forests about Para in the lower Amazon are typicn1 in this respect, yet they abound with the most gorgeously coloured butterflies, almost all of which frequent the forest depths, keeping nea.r the ground, where there is the greatest deficiency of brilliant flowers. In contrast with this let n take the Cape of Good Hope-the most flowery region probably that exists UJ on the globc,-where the country is a complete flower-garden of heaths, pelargoniums, mesembryanthemus, exquisite iridaceous and other bulbs, and numerous flowering shrubs and trees; yet the Cape butterflies are hardly equal, either in number or variety, to those of any country in • 'outh Europe, and are utterly insignificant when compared with those of the comparatively flowerless forest-depths of the Amazon or of Now Guinea. Neither is there any relation between the colours of other insects and their haunts. Few 1 The Colo1~r Sense, chap. ix.. |