Cites cases of difference in coloration between the sexes of some species of Crustacea, annelids, and spiders.

Discusses dimorphic plants and self-sterility.

Outlines some experiments involving the crossing of different species of orchids.

Encloses extract from Carl Claus, Die freilebenden Copepoden [1863].

Thanks for "Climbing plants" offprint and for references on fertilisation of flowers.

Considering the bounty of work already done, he is looking for something original to do.

Subularia does not grow in Westphalia.