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Show CHAPTEh IX WARNING COLORATION AND MIMICRY The skunk as an cxalllplo of warning coloration-Warning colours al!long in. ccLs - BnLterllics- OaLcrpillars- Mimicry- liow min1icry has ht>cn prodtH'C\1--1 fcliconitlrc- PerfceLioH of tho imitation Other case;; of mimicry am011g Lcpi(loptcra- Mirnicry among protccled groups ] ls explanation - Rxtcnsion of the principle-Mimicry in oth er onh•rs of insects-Mimicry among the vcrtcbmta- Silakes- Thc ratLles11ako and tho cobra- Mimicry among birds- Obj ections to the th eo ry of mimicry-Oonclmling remarks ou waming colours an\l milllicry. WI~ ha.vo now to doni with a class of colours which arc tho very opposite of those we have hitherto consiclcrocl, sirr ec, insto:t.d of serving to conceal the animals that posse s them or as recognition marks to their associa,to , they <tro developed for the express purpose of rendering the species conspicuous. The rca,son of this is th::.tt tho animals in question arc either the possessors of some deadly weapons, as . tings or poison fangs, or they are uneatable, and arc thus so cli:-;:Lgreuablc to the ustml enemies of their kind that they arc never attacked when their peculiar powers or properties arc known. It is, therefore, important that they should 110t JJe mist: Lkcn for dcfoncelc · or oa,table species of tho same class or ot-.ler, since iu that ca:c they might suffer injury, or oven dent lr, hcforc theie enemies discovered tho chngor or the uselc:-;snc~s of the attack. They require some signaJ or· <hrwer-flag which sh:tll serve as a warning to would- be enemies not to attack them, and they have usually obtained this in the form of conspicuous or brilliant coloration, vel'y distiuet from tho protodi vc ti11 ts of tho defenceless animals allied to them. CIIAP. IX W ARNINO COLOH.A'l'lON AND MIM lORY 233 The Slcunlc as ill~tstmting l:V arning Colomtion. While staying a few days, in July 1887, at the Summit Hotel on tho Central Pa,cific Hail wa,y, I strolled out one evening <Liter dinner, and on the road, not fifty yards from tho house, I saw a pretty little white and black animal with a bushy tail coming towards mo. As it came on at a slow pace and without any fear, although it evidently saw me, I thought at first that it must be some tame creature, when it suddenly occurred to me that it was a skunk It came on till within five or six yarJ.s of me, then quietly climbed over a dwarf wall and disappeared under a small outhouse, in search of chickens, as the landlord afterwards told me. This animal possesses, as is well known, a most offensive secretion, which it has the power of ejecting over its enemies, and which eflcctually protects it from attack Tho odour of this substance is so penetrating that it taints, and renders useless, everything it touches, or in its vicinity. Provisions ncar it become unoa.tablc, and clothes saturated with it will retain the smell for several weeks, even though they arc repeatedly washed a.nd dried. A drop of the liquid in tho eyes ·will cause blindness, and Indians arc said not unfrcquently to lose their sight from this cause. Owing to this remarkable power of offence the skunk is rarely att~tcked by other animals, and its black and white fur, and tho bushy white tail carried erect when disturbed, form the danger-signals by which it is crtsily distinguished in the twilight or moonlight from unprotected animals. Its consciousness that it needs only to 1 o seen to be avoid d rrives it that slowness of motion <tnd fearlessness of aspect which arc, as we shall see, characteristic of most creatures so protected. JVa1·ning Colmt?'S among Insects. It is among insects that waming colours are best dovclopocl, and most abundant. \V c all know how well mnrkc<l and conspicuous arc the colonrs <tncl forms of the stinging wn.sps and boos, ILO one of which in any prwt of tho world is known to be protectively coloured like the majority of dcfenc le. s insects. Most of tho great tribe of Malaeo<lcrms umong beetles are distasteful to insed-cating animals. Om rc<l ttrHl |