If this be so, then do not answer; and I will so understand it.
LETTER 62.

TO J.D.HOOKER.

February 23rd [1858].
Will you think of some of the largest genera with which you are well acquainted, and then suppose 4/5 of the species utterly destroyed and unknown in the sections (as it were) as much as possible in the centre of such great genera.

Then would the remaining 1/5 of the species, forming a few sections, be, according to the general practice of average good Botanists, ranked as distinct genera?
Of course they would in that case be closely related genera.

The question, in fact, is, are all the species in a gigantic genus kept together in that genus, because they are really so very closely similar as to be inseparable?
or is it because no chasms or boundaries can be drawn separating the many species?
The question might have been put for Orders.
LETTER 63.