[79]

Paolo Bonizzi — Le Variazioni of Domestic Pigeon 1873

p. 132 add to note (3) – give number of var. I think only coloured ones vars.

[Variation 2d ed. 1: 170: "Dr. Chapuis also remarks34 that in certain light-coloured pigeons the males have their feathers striated with black, and these striæ increase in size at each moult, so that the male ultimately becomes spotted with black.
34 'Le Pigeon Voyageur Belge,' 1865, p. 87. I have given in my 'Descent of Man' (6th edit. p. 466) some curious cases, on the authority of Mr. Tegetmeier, of silver-coloured (i.e. very pale blue) birds being generally females, and of the ease with which a race thus characterised could be produced. Bonizzi (see 'Variazioni dei Columbi domestici:' Padova, 1873) states that certain coloured spots are often different in the two sexes, and the certain tints are commoner in females than in male pigeons."]