CD sends thanks for Manual of European butterflies [1862].

Is pleased that WFK does not believe in immutability of species, "a doctrine perfectly adapted to stop philosophical research", and hopes he will publish further.

Notes WFK’s name is the same as the entomologist’s.

CD is particularly struck by WFK’s observations on Corsican and N. American subspecies in his paper ["On the geographical distribution of European Rhopalocera", Trans. R. Entomol. Soc. Lond. 3d ser. 1 (1862–3): [!?bib has 1862–4] 481–92]. Thinks it would be interesting for WFK to examine specimens from the Shetland Islands, for even faint trace of differentiation.

Describes some cases of geographical distribution of butterflies. Raises the perplexing question of the distribution of Pyrameis atalanta in Europe and P. calliroe in the Canaries.