What two very interesting and useful letters you have sent me. You rather astound me with respect to value of grounds of generalisation in the morphology of plants. It reminds me that years ago I sent you a grass to name, and your answer was, "It is certainly Festuca (so-and-so), but it agrees as badly with the description as most plants do." I have often laughed over this answer of a great botanist...Lindley, from whom I asked for an orchid with a simple labellum, has most kindly sent me a lot of what he marks "rare" and "rarissima" of peloric orchids, etc., but as they are dried I know not whether they will be of use. He has been most kind, and has suggested my writing to Lady D. Nevill, who has responded in a wonderfully kind manner, and has sent a lot of treasures. But I must stop; otherwise, by Jove, I shall be transformed into a botanist. I wish I had been one; this morphology is surprisingly interesting. Looking to your note, I may add that certainly the fifteen alternating bundles of spiral vessels (mingled with odd beadlike vessels in some cases) are present in many orchids. The inner whorl of anther ducts are oftenest aborted. I must keep clear of Apostasia, though I have cast many a longing look at it in Bauer. (606/1. Apostasia has two fertile anthers like Cypripedium. It is placed by Engler and Prantl in the Apostasieae or Apostasiinae, among the Orchideae, by others in a distinct but closely allied group.) I hope I may be well enough to read my own paper on Thursday, but I have been very seedy lately. (606/2. "On the two Forms, or Dimorphic Condition, in the Species of the Genus Primula," "Linn. Soc. Journ." 1862. He did read the paper, but it cost him the next day in bed. "Life and Letters," III., page 299.) I see there is a paper at the Royal on the same night, which will more concern you, on fossil plants of Bovey (606/3. Oswald Heer, "The Fossil Flora of Bovey Tracey," "Phil. Trans. R. Soc." 1862, page 1039.), so that I suppose I shall not have you; but you must read my paper when published, as I shall very much like to hear what you think. It seems to me a large field for experiment. I shall make use of my Orchid little volume in illustrating modification of species doctrine, but I keep very, very doubtful whether I am not doing a foolish action in publishing. How I wish you would keep to your old intention and write a book on plants. (606/4. Possibly a book similar to that described in Letter 696.) LETTER 607. TO G. BENTHAM. Down, November 26th [1861].