Note 69 — Chapter XVII · ON THE GOOD EFFECTS OF CROSSING, AND ON THE EVIL EFFECTS OF CLOSE INTERBREEDING.
Reading edition
‘Proc. Bot. Soc. of Edinburgh,’ May, 1863: these observations are given in abstract, and others are added, in the ‘Journal of Proc. of Linn. Soc.,’ vol. viii. Bot., 1864, p. 162.