Note 35 — Chapter V · DOMESTIC PIGEONS.
Reading edition
Prof. A. Newton (‘Proc. Zoolog. Soc.,’ 1865, p. 716) remarks that he knows no species which present any remarkable sexual distinction; but Mr. Wallace informs me, that in the sub-family of the Treronidæ the sexes often differ considerably in colour. See also on sexual differences in the Columbidæ, Gould, ‘Handbook to the Birds of Australia,’ vol. ii., pp. 109-149.