I will send you a copy of my paper on Physiological Selection as soon as I return to London, which will be about Christmas.
With many thanks for your kindness, I remain, yours truly,
G. J. Romanes.
May 7, 1888.
My dear Sir,—Many thanks for sending me a copy of your book,[66] which seems to me everywhere admirable. Of course, I am particularly glad that you think with me so much on physiological selection, but even apart from this, the work is, to my mind, one of the most clearly thought out that I have met with in Darwinian literature. I have sent it on to 'Nature' for review, understanding from the office that a copy had not then been received. But for your kind mention of myself, I should have reviewed it.
A most remarkable paper has been sent to the Linnean Society by a Mr. Gulick on 'Divergent Evolution,' for the publication of which in the 'Journal' you might look out.
G. J. Romanes.
January 21, 1889.
My dear Sir,—I should like you to set your lucid wits to work upon the following questions, and let me know whether you can devise any answers.
On pp. 220-226 of your book, you state with extreme felicity, and much better than he does, Weismann's theory of the causes of variation. But it does not occur to him, and does not seem to have occurred to you, that there is a curious and unaccountable interruption in the ascending grades of sexual differentiation, for in the vegetable kingdom these do not follow the grades of taxonomic ascent; but, on the contrary, and as a general rule, the lower the order of evolution, the greater is the tendency to bi-sexualism. Diœcious species (i.e. male and female organs on different plants) occur in largest proportion among the lower Cryptogams, less frequently among the higher, and more rarely still among Phanerogams. Monœcious species (i.e. male and female organs on the same plant, but locally distinct) occur chiefly among the higher Cryptogams and lower Phanerogams; Hermaphrodite species (i.e. male and female organs in the same flower) occur much more frequently among higher Phanerogams.