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Show 202 SEXUAL SELECTION: BIRDS. PART II. tions made- in China by Mr. Swinhoe.15 Mr. Blyth believes, that the young of both sexes resemble the adult male. · d s · The females of the three species of Pamte ~lpos (Rhynchroa) "arc not only larger, but much more nchly \l l ~ -,,~ - Fig. 60. Huynclulla cnpensis (!'rom Brehm). " coloured than the males." 16 With all other birds, in which the trachea differs in structure in tho two sexes 1~ Jordon,' Birds of India,' vol. iii. p. 596. Mr. Swinboc. in' lbis,' 1 G5, p. 542; 1866, p. 131, 405. 16 Jordon, 'Birds(of Indin,' vol. iii. p. G77. UuAP. XVI. THE YOUNG LIKE THE ADULT MALES. 203 it is more developed and complex in the male than in the female; but in the Rhyncluea Australis it is simple in the male, whilst in the female it makes four distinct convolutions before entering the lungsY The female therefore of this species has acquired an eminently masculine character. Mr. Blyth ascertained, by examining many specimens, that the trachea is not convoluted in either sex of R. Bengalensis, which species so closely resembles R. Australis that it can hardly be distinguished except by its shorter toes. This fact is another striking instance of the law that secondary sexual characters are often widely different in closelyallied forms ; though it is a very rare circumstance when such differences relate to the female sex. The young of both sexes of R. Bengalensis in their first plumage are said to resemble the mature male.18 'fhere is also reason to believe that the male undertakes the duty of incubation, for Mr. Swinhoe 19 found the females before the close of the summer associated in flocks, as occurs with the females of the Turnix. The females of Phalaropus fulicarius and P. hyperboreus are larger, and in their summer pi umage "more gaily "attired than the males.'' But the difference in colour between the sexes is far from conspicuous. The male alone of P. fulicarius undertakes, according to Professor Steenstrup, the duty of incubation, as is likewise shewn by the state of his breast-feathers during the breedingseason. The female of the dotterel plover (Eudromias morinellus) is larger than the male, and has the red and black tints on the lower surface, the white crescent on the breast, and the stripes over the eyes, more strongly pronounced. The male also takes at least a 17 Gould's 'Handbook of tho Birds of Australia> vel. ii. p. 275. 18 'The Indian Field,' Sept. 1858, p. 3. 10 'Ibis,' 1866, p. 298. |