An orchid which I missed last year, Platanthera flava, I knew would be curious, for I remembered a strong protuberance on base of labellum, on the median line. I have not time left to describe it now, having been sadly interrupted, but it is pretty,—equal to anything you have yet seen in British orchids. The process turns proboscis of insect either to right or left, where it will slip into an imperfect ring (as seen from above) or deep groove (as seen from before), in which lies the disk, not flat but coiled up, ready to catch proboscis. It is like the eye of a needle to receive the thread.
Perhaps I will send you, or print, a sketch[56] of the thing.
I am waiting for Gymnadenia tridentata to come on.
But the post hour has come.
July 21.
Your latest is of the 26th ult. You need not worry! It never wearies nor bores me to write to you, in the off-hand way I do. I enjoy our correspondence too much to consent to curtail or interrupt it. I learn from you, here in this remote part of the world, a thousand things which I should not otherwise know at all. And you stimulate my mind far more than any one else, except, perhaps, Hooker. So please do not make a fuss, but let me go on in my own fashion, and send me your fresh and stimulating letters, whenever you are in the mood of it. I am now in my vacation, and already, having idled and dawdled a week or two, I am as well and hearty as possible, and in the best of spirits. We should leave home this week for three weeks’ run in the country, but the sickness of my wife’s nephew, Lieutenant Jackson of Massachusetts Cavalry, will keep us awhile, as, though not alarming, it might take a bad turn, and so I may not be in the country for a week or two yet. We shall see....
I have strong and fresh Drosera rotundifolia, and it will now turn in its bristles and stick the viscid gland fast to a fly, binding him fast on all sides with liliputian cords. But it is awfully slow about it,—say three or four hours, and the next day the leaf sometimes becomes involute and folds over or curves around the insect; but what good? If the fly is not stuck fast in alighting, no movement takes place to hold him till he has got away if he ever could. However, it is an indication of what is so effectually done in Dionæa.
Rotary movement of end of tendril-bearing stems is common, is it not, and well-known?
Any notes you will give me to print in “Silliman’s Journal,” I shall always delight in.
I have been reading Owen’s Aye-aye paper. Well, this is rich and cool! Did I not tell you in the “Atlantic,” long ago, that Owen had a transmutation theory of his own! It is your Hamlet, with the part of Hamlet left out! But as you say now, you don’t so much insist on natural selection, if you can only have derivation of species. And Owen goes in for derivation on the largest scale. You may as well lovingly embrace! Oh, it is rare fun!...