10. GEOGRAPHY? No.
11. MILITARY MOVEMENTS? No.
12. MECHANISM? Never tried.
13. GEOMETRY? I do not think I have any power of the kind.
14. NUMERALS? When I think of any number, printed figures arise before my mind. I can't remember for an hour four consecutive figures.
15. CARD PLAYING? Have not played for many years, but I am sure should not remember.
16. CHESS? Never played.
[In 1880 he published a short paper in 'Nature' (volume xxi. page 207) on the "Fertility of Hybrids from the common and Chinese goose." He received the hybrids from the Rev. Dr. Goodacre, and was glad of the opportunity of testing the accuracy of the statement that these species are fertile inter se. This fact, which was given in the 'Origin' on the authority of Mr. Eyton, he considered the most remarkable as yet recorded with respect to the fertility of hybrids. The fact (as confirmed by himself and Dr. Goodacre) is of interest as giving another proof that sterility is no criterion of specific difference, since the two species of goose now shown to be fertile inter se are so distinct that they have been placed by some authorities in distinct genera or sub-genera.
The following letter refers to Mr. Huxley's lecture: "The Coming of Age of the Origin of Species" (This same "Coming of Age" was the subject of an address from the Council of the Otago Institute. It is given in 'Nature,' February 24, 1881.), given at the Royal Institution, April 9, 1880, published in 'Nature,' and in 'Science and Culture,' page 310:]
CHARLES DARWIN TO T.H. HUXLEY. Abinger Hall, Dorking, Sunday, April 11, 1880.