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Show 204 SEXUAL SELECTION: BIRDS. PART II. share in hatching the eggs; but the female likewi~e attends to the young.20 I have not been able to discover whether with these species the young resemble the adult males more closely than the adult females; for tho comparison is somewhat difficult to make on account of the double moult. Turnincr now to the Ostrich order: the male of the com- o mon cassowary ( Oasuarius galeatus) would be thought by any one to be the female, from h~s smaller s_ize and from the appendages and naked skm about ~11~ head being much less brightly coloured; anJ. I am mfor~e~ by Mr. Bartlett that in the Zoological Gardens 1t 1s certainly the male alone who sits on the eggs and takes care of the young.21 The female is said by Mr. T. W. vVood 22 to exhibit during the breeding-season a most pucrnacious disposition ; and her wattles then become eniarged and more brilliantly coloured. So again the female of one of the emus (Dromceus irroratus) is considerably larger than the male, and she possesses a slight top-knot, but is otherwise undistinguishable in plumage. She appears, however, "to have greater power, when angry "or otherwise excited, of erecting, "like a turkey-cock, the feathers of her neck and 2o For these several statements, sec Mr. Gould's 'Birds of Grent Britain.' Prof. Newton informs me that he has long been convinced, from his own observntions and from those of others, that the males of the above-named species take either the whole or a large share of tho duties of incubation, and thA.t they ''shew much greater devotion "towards their young, when in danger, than do the females.'' So it is, as he informs me, with Limosa lapponica and some few other Waders, in which the femnles arc larger and have more strongly contrasted colours than the mnlcs. 21 Tho natives of Ceram (Wallace, 'MalA.y Archipelago,' vol. ii. p. 150) assert that the malo and female sit alternately on tho eggs; but this nssertion, ns Mr. Bartlett thinks, may be accounted for by the female visiting then st to lay her eggs. 22 'The Student,' April, 1870, p. 124. CHAP. XVI. THE YOUNG LIKE TilE ADUL'r MALES. 205 " breast. She is usually the more courageous and "pugilistic. She makes a deep hollow guttural boom, "especially at night, sounding like a small gong. The "male has a slenderer frame and is more docile, with " no voice beyond a suppressed hiss when angry, or a " croak." He not only performs the whole duty of incubation, but has to defend the young from their mother; "for as soon as she catches sight of her pro" geny she becomes violently agitated, and notwith" standing the resistance of the father appears to use "her utmost endeavours to destroy them. For months "a~terwards it is unsafe to put the parents together, "vwlent quarrels being the inevitable result, in which ':tho female generally comes off conqueror." 23 So that with this emu we have a complete reversal not <>nly of the parental and incubating instincts, but of the usual moral qualities of tho two sexes ; the females being savage, quarrelsome and noisy, the males gentle and good. The case is very different with the African ostrich, for the male is somewhat larger than the female and has finer plumes with more strongly contrasted colours; nevertheless he undertakes the whole duty of incubation.24 I will specify the few other cases known to me in · which the female is more conspicuously coloured than the male, although nothing is known about their manner of incubation. With the carrion-hawk of the Falkland Islands. (Milvago Zeucurus) I was much surprised to find by dissection that the indivirluals which had all their tints strongly pronounced, with the core and legs orange-coloured, -\vere the adult females; whilst 23 See the excellent account of the habits of this bird under confinem~~ t, by Mr. A. W. Benne_tt, in '~and and Water,' May, 1868, p. 233. Mr. Sclater, on the meubat10n of the Struthiones 'Proc. Zoo. Soc.,' June 9, 1863. ' |