any general
remark, and if I find it confirmed in any other very distinct class,
then I try to find out whether it is true,--if it has any bearing on my
work. The following, perhaps, may be important to me. Dr. Wight remarks
that Cucurbitaceae (55/1. Wight, "Remarks on the Fruit of the Natural
Order Cucurbitaceae" ("Ann. Mag. Nat. Hist." VIII., page 261). R. Wight,
F.R.S. (1796-1872) was Superintendent of the Madras Botanic Garden.)
is a very isolated family, and has very diverging affinities. I find,
strongly put and illustrated, the very same remark in the genera of
hymenoptera. Now, it is not to me at first apparent why a very distinct
and isolated group should be apt to have more divergent affinities than
a less isolated group. I am aware that most genera have more affinities
than in two ways, which latter, perhaps, is the commonest case. I see
how infinitely vague all this is; but I should very much like to know
what you and Mr. Bentham (if he will read this), who have attended so
much to the principles of classification, think of this. Perhaps the
best way would be to think of half a dozen most isolated groups of
plants, and then consider whether the affinities point in an unusual
number of directions. Very likely you may think the whole question too
vague to be worth consideration.

LETTER 56. TO J.D. HOOKER. Down, April 8th [1857].

I now want to ask your opinion, and for facts on a point; and as I shall
often want to do this during the next year or two, so let me say, once
for all, that you must not take trouble out of mere good nature (of
which towards me you have a most abundant stock), but you must consider,
in regard to the trouble any question may take, whether you think it
worth while--as all loss of time so far lessens your original work--to
give me facts to be quoted on your authority in my work. Do not think
I shall be disappointed if you cannot spare time; for already I have
profited enormously from your judgment and knowledge. I earnestly beg
you to act as I suggest, and not take trouble solely out of good-nature.

My point is as follows: Harvey gives the case of Fucus varying
remarkably, and yet in same way under most different conditions. D. Don
makes same remark in regard to Juncus bufonius in England and India.
Polygala vulgaris has white, red, and blue flowers in Faroe, England,
and I think Herbert says in Zante. Now such cases seem to me very
striking, as showing how little relation some va