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Show 30 SEXUAL SELECTION. PART JL In the 'l'?'Cigops clispa?· of tho same country, the male is lm·g ht green, and tho female bronze-co 1o m·o c! 5· ° .N o doubt the colonrs of some nakes servo as a protectwn, as the green tints of tree-snakes and tho Yarious mottled shades of tlw species which live in Fandy pla?es; but it is doubtful whether tho colours of many kmds, for in tance of the common E1wli h snake or viper, serv to conceal them· and this ~ still more doubtful with the many forcig~ species which are coloured with ex-treme elegance. . Durinrr tho breeding-season then· anal scent-glands are in a~tive function ;51 and so it is with the same glands in lizards, anu as we have seen with th~ submaxillary glands of crocodile. . . As the 1~1nles of most animal~ search for the fomaleR, these odonferous gland probably serve to excite or charm the female, rather than to guide her to the spot where t~e male may. be founcP2 :M:ale snake , though appearmg so slugg1sh, are amorous ; for many have been observed crowuing round the same female, and even round the dead body of a female. They are not known to :fight together from rivalry. Their intellectual powers are higher than mi{)'ht have been anticipated. An excellent observer in Ceylon, Mr. E. Layard,53 saw a Cobra thrust its head through a narrow hole and swallow a toad. " With uo Dr. A. Gunther, 'RcptilcH of British Imlin,' Ray Roc. lSG.J:, p. 304, 30!;. 61 Owen,' Anatomy of Vcrtobrutcs,' vol. i. ISGG, p. 615. "~ Tho ce1ebratcd botanist , chlcidcn incidently rcmnr1;s ('Ueber uen Darwinismus: Unsero Zeit,' 18GD, s. 2GD), tliat Rrtttlc-snakes usc their rattles as n. sexual call, by which the two sexes find each other. I do not know whether this suggestion rests on any direct observations. 'fhese , nnkes pair in the Zoological Gardens, but the keepers have never observed that they me their rattles at this season morC' than at nny other. r,:1 "lhmbl sin Ceylon," 'Annal~ and 1\'lag. of Nat. Ilist.' 2nti series, vol. ix. 1852, p. 333. 'HAP, Xll. REPTILE'. 31 "this iucnmbrance he could not withdraw himself; "finding this, he J·cluctantly di ·gorge<l the precious "morsel, which began to move off; this was too much " for snake philosophy to bear, and the toad was ngain ''seized, a11d again was tho snake, after violent efforts "io escape, compelled to part with its prey. Thi.' time, c: lt0\1 ever, a lesson had been leamt, and the toad wa. · "seized by one leg, withdrawn, and then swallowed in "triumph." lt docs not, however, follow becanse snakes have some reasoning power and strono· passions that they should likewise be endowed with sufficie~t taste to atlmirc brilliant colours in their partners, so as to lead t:o tho adornment of the species through sexual sclectwn. N everthcless it is difficult to account iu any .other ~anner for the extreme beauty of certain spoe1es; for mstance, of the coral-snakes of S. America which arc of a rich red with black and yellow transvers; bands. I well remember how much surprise I felt at the beauty of the first coral-snake which I saw o·lidin{)' across a path in Brazil. Snakes colomed in this p~culia~· manner, as lVIr. Wallace states on tho authority of Dr. · ? ilnther,M ~re found nowhere else in the world except m S. Amerwa, and here no less than four genera occur. O.ne. of these, Elaps, is venomou ; a second and wiclelydistmct genus is doubtfully venomous, and the two others a:e quite har~less.. The species belonging to these distmct genera mhab1t the same districts, and are so like each other, that no one ''but a naturalist would clistin" guish the harmless from the poisonous kinds." Hence as Mr. \Val~ace beli:Yes, the innocuous kinds have pro~ ba?lY: acqmred. the1r colours as a protection, on the prmmplo of imitation; for they would naturally Le 54 'Westminster Review,' July lst, 18G7, p. 32. |