74 MR. R. STAPLES-BROAYNE ON [Feb. 18, 



Types of Birds produced in the Barb-Fantail Cross. 



The birds produced in this cross fell naturally into five classes — 

 black, blue, dun, red, and white. Of these the black, blue, and 

 white are chiefly dealt with in the present paper. 



Coloured birds are divided into two classes ; those with some 

 white feathers in the plumage, and those without white. The 

 white birds are similai-ly divided into those having some coloured 

 feathers, and those with none. 



It was possible to see to which type a bird belonged at an 

 early age. 



The descriptions of the types which follow include the more 

 striking variations noticed in individuals. 



1. Blacks. 



The blacks produced in these crosses were generally of a rich 

 deep colour similar in all respects to that found in the Barb. They 

 possessed the green and purple iridescence on the neck which is 

 commonly seen in all dark types of domestic pigeons. There 

 were, however, certain birds produced, which are specially noted 

 in Exps. 27 and 32, bred from the mating of black and blue, 

 which were of a smoky or sooty black colour. In some of these 

 birds wing-bars of a darker shade of black were observed. The 

 tail-bar was observed on one specimen only. 



2. Bhies. 



The birds classed as blue in the following experiments were 

 not identical with Columha livia, as were the birds, produced by 

 Darwin, referred to in the introduction. Their genei-al colour 

 was a smoky black with blue tail and black tail-bar. Laying aside 

 the details of the distribution of white when present, which is 

 dealt with below, the series of blue birds produced was very 

 uniform in type. Slight variations occurred in the shade of the 

 bkie colour, and the substitution of chequered feathers {i. e. blue 

 feathers edged with a variable amount of black) for the smoky 

 black of the wing-coverts. These points were not very distinctive : 

 they are, however, noted under the experiments in which they 

 occurred. The head and upper part of the neck were generally 

 bluish, slightly daiker than in C. livia, but varying to a smoky 

 black. The lower part of the neck, upper part of the back, wings, 

 and upper part of the breast smoky black. The wing-bars were 

 generally obscured, but in some specimens could be distinguished. 

 The lower part of the breast, lower part of the back and abdomen 

 were blue, occasionally with slight chequering. 



The rump was blue, sometimes of a lighter shade than that in 

 other parts of the body. The flanks, thighs, vent, upper and 

 under tail-coverts were blue. The tail-feathers were blue with a 

 black bar, which was sometimes terminal, but more usually a 



