See page 15 of separate copy: "We should then have the present races represented by the countless branchlets forming the flat-topped summit" of a genealogical tree, in which "all we can do is to map out the summit as it were from a bird's-eye view, and under each cluster, or cluster of clusters, to place as the common trunk an imaginary type of a genus, order, or class according to the depth to which we would go.") My recent work leads me to differ from him on one point--viz., on the separation of the sexes.

(259/3.

On the question of sexuality, see page 10 of Bentham's address.

On the back of Mr.Darwin's copy he has written: "As long as lowest organisms free--sexes separated: as soon as they become attached, to prevent sterility sexes united--reseparated as means of fertilisation, adapted [ ?] for distant [ ?] organisms,--in the case of animals by their senses and voluntary movements,--with plants the aid of insects and wind, the latter always existed, and long retained." The two words marked [ ?] are doubtful.

The introduction of freedom or attachedness, as a factor in the problem also occurs in "Cross and Self-fertilisation," page 462.