ck with
admiration at your powers of observation.

The discussion on mimetic insects seems to me particularly good and
original. Pray accept my cordial thanks for the instruction and interest
which I have received.

What a loss to Natural Science our poor mutual friend Walsh has been; it
is a loss ever to be deplored...

Your country is far ahead of ours in some respects; our Parliament would
think any man mad who should propose to appoint a State Entomologist.

LETTER 707A. TO C.V. RILEY.

(706A/1. We have found it convenient to place the two letters to Riley
together, rather than separate them chronologically.)

Down, September 28th, 1881.

I must write half a dozen lines to say how much interested I have been
by your "Further Notes" on Pronuba which you were so kind as to send me.
(706A/2. "Proc. Amer. Assoc. Adv. Sci." 1880.) I had read the various
criticisms, and though I did not know what answer could be made, yet I
felt full confidence in your result, and now I see that I was right...If
you make any further observation on Pronuba it would, I think, be well
worth while for you to observe whether the moth can or does occasionally
bring pollen from one plant to the stigma of a distinct one (706A/3.
Riley discovered the remarkable fact that the Yucca moth (Pronuba
yuccasella) lays its eggs in the ovary of Yucca flowers, which it has
previously pollinated, thus making sure of a supply of ovules for the
larvae.), for I have shown that the cross-fertilisation of the flowers
on the same plant does very little good; and, if I am not mistaken,
you believe that Pronuba gathers pollen from the same flower which she
fertilises.

What interesting and beautiful observations you have made on the
metamorphoses of the grasshopper-destroying insects.

LETTER 707. TO F. HILDEBRAND. Down, February 9th [1872].

Owing to other occupations I was able to read only yesterday your
paper on the dispersal of the seeds of Compositae. (707/1. "Ueber die
Verbreitungsmittel der Compositenfruchte." "Bot. Zeitung," 1872, page
1.) Some of the facts which you mention are extremely interesting.

I write now to suggest as worthy of your examination the curious
adhesive filaments of mucus emitted by the achenia of many Compositae,
of which no doubt you are aware. My attention was first called to the
subject by the achenia of an Australian Pumilio (P. argyrolepis), which
I briefly described in the "Gardeners' Chronicle," 1861, page 5. A