Hopes GdeS will publish on subjects discussed in his letter . CD had noted similar persistence of variation in fossil shells.
Calls his attention to Nägeli’s work on Hieracium.
Expresses skepticism about O. Heer’s view that dicotyledonous plants developed suddenly. Believes they must have developed slowly in some part of the globe completely isolated from other regions.
The full text of this letter is not yet available online.