My dear Sir
I write a line to thank you sincerely for your two notes.— Very curious your facts about the crossing the Game Fowls. Good Heavens what a hopelessly difficult subject is that of inheritance!
The crosses from Spanish & Silk Hen are all black-combed, & as you say not silky feathers.—2
I crossed the Barbs which you had (ie plain-headed) the parents of which got 2d prize at C. Palace, & likewise the turn-comded3 Barbs with the Fan-tails, & recrossed their offspring, but I cannot positively say, from which I procured the blue-bird.4 The turn-commed were from Sir J. Sebrights. & it is simple nonsense to say they were not pure.5 It was a notion which Mr Brent got owing to a German author (of whom I told him) saying this cross was sterile.6 The one German Book is a very poor one & no particulars are given.— When Mr Brent gets a notion into his head nothing gets it out.—
In Haste | Yours very sincerely | C. Darwin
P.S I have just remembered positively that I reared several mongrels from the plain-headed Barbs & Fantails. I have several other cases of blueish birds reared from other crosses of other kinds not given in my abstract.—7
Please cite as “DCP-LETT-2712,” in Ɛpsilon: The Charles Darwin Collection accessed on