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in PROTECTIVE RESEMBLANCES AMONG ANIMALS 39Special Modifications of ColawrThe conformity of tint which has been so far shown toexist between animals and their habitations is of a somewhatgeneral character; we will now consider the cases of morespecial adaptation. If the lion is enabled by his sandycolour readily to conceal himself by merely crouching downupon the desert, how, it may be asked, do the elegant markingsof the tiger, the jaguar, and the other large cats, agreewith this theory ? We reply that these are generally casesof more or less special adaptation. The tiger is a jungleanimal, and hides himself among tufts of grass or of bamboos,and in these positions the vertical stripes with which hisbodyis adorned must so assimilate with the vertical stems ofthe bamboo as to assist greatly in concealing him from hisapproaching prey. 1 How remarkable it is that besides thelion and tiger, almost all the other large cats are arboreal intheir habits, and almost all have ocellated or spotted skins,which must certainly tend to blend them with the backgroundof foliage ;while the one exception, the puma, has an ashy.brown uniform fur, and has the habit of clinging so closelyto a limb of a tree while waiting for his prey to pass beneathas to be hardly distinguishable from the bark.Among birds, the ptarmigan, already mentioned, must beconsidered a remarkable case of special adaptation. Anotheris a South American goatsucker (Caprimulgus rupestris), whichrests in the bright sunshine on little bare rocky islets in theUpper Kio Negro, where its unusually light colours so closelyresemble those of the rock and sand that it can scarcely bedetected till trodden upon.The Duke of Argyll, in his Eeign of Law, has pointed outthe admirable adaptation of the colours of the woodcock toits protection. The various browns and yellows and paleash-colour that occur in fallen leaves are all reproduced in itsplumage, so that when, according to its habit, it rests uponthe ground under trees, it is almost impossible to detect it.In snipes the colours are modified so as to be equally inharmony with the prevalent forms and colours of marshyvegetation. Mr. J. M. Lester, in a paper read before the1 This suggestion has been since confirmed. See Darwinism, p. 199.