useful. I shall be sorry (and I am certain it is a mistake on the
part of the Society) if your orchid paper is not printed in extenso.
I am now at work compiling all such cases, and shall give a very full
abstract of all your observations. I hope to add in autumn some from
you on Passiflora. I would suggest to you the advantage, at present,
of being very sparing in introducing theory in your papers (I formerly
erred much in Geology in that way): LET THEORY GUIDE YOUR OBSERVATIONS,
but till your reputation is well established be sparing in publishing
theory. It makes persons doubt your observations. How rarely R. Brown
ever indulged in theory: too seldom perhaps! Do not work too hard,
and do not be discouraged because your work is not appreciated by the
majority.

LETTER 647. TO J. SCOTT. July 2nd [1863?]

Many thanks for capsules. I would give table of the Auricula (647/1.
In Scott's paper ("Linn. Soc. Journ." VIII.) many experiments on the
Auricula are recorded.), especially owing to enclosed extract, which you
can quote. Your facts about varying fertility of the primulas will be
appreciated by but very few botanists; but I feel sure that the day will
come when they will be valued. By no means modify even in the slightest
degree any result. Accuracy is the soul of Natural History. It is hard
to become accurate; he who modifies a hair's breadth will never be
accurate. It is a golden rule, which I try to follow, to put every fact
which is opposed to one's preconceived opinion in the strongest light.
Absolute accuracy is the hardest merit to attain, and the highest merit.
Any deviation is ruin. Sincere thanks for all your laborious trials on
Passiflora. I am very busy, and have got two of my sons ill--I very much
fear with scarlet fever; if so, no more work for me for some days or
weeks. I feel greatly interested about your Primula cases. I think it
much better to count seed than to weigh. I wish I had never weighed;
counting is more accurate, though so troublesome.

LETTER 648. TO J. SCOTT. Down, 25th [1863?]

From what you say I looked again at "Bot. Zeitung." (648/1. "Ueber
Dichogamie," "Bot. Zeit." January 1863.) Treviranus speaks of P.
longiflora as short-styled, but this is evidently a slip of the pen, for
further on, I see, he says the stigma always projects beyond anthers.
Your experiments on coloured primroses will be most valuable if proved
true. (648/2. The reference seems to be to Scott's observation t