I note with satisfaction what you write about genera of ferns. This pushing a single character (as venation) without regard to consequences, and giving it the same importance when it does not accord with habit as when it does, is the fault of most botanologists who restrict their view to one subject or one idea only. I am glad that you will carefully revise the genera on your own judgment. By the way, the fern I sent you last spring, and which you called Asplenium montanum, Willd. (a species I used to know well), struck the collector (Beaumont), as it did me, to be different. Pray collate, and perhaps figure it, as well as the ordinary A. montanum. I was grieved to hear of the death of Adr. de Jussieu, with whom I have had a very pleasant correspondence for the last three years, and to whom I was attached as to no other Frenchman. His late letters were so cheerful and lively, and even hopeful, that the news of his death took me by surprise, notwithstanding the steady failure of his health for a long while.... We remember with interest that dear Harvey sets out to-morrow on his long voyage. TO R. W. CHURCH. Christmas Eve, 1853. MY DEAR MR. CHURCH,--It is a good time to remember old friends and to bring up, as well as one may, arrears of neglected duty. I have long unaccountably neglected to acknowledge your letter of the 24th August, and to thank you most heartily for the interesting volume of your collected reviews, which reached me a little earlier (I know not how it was so long delayed between New York and Cambridge), and which I have received and read with much pleasure, that is, all I have yet read. For I am saving the article on Dante for my first leisure hour. The first I read was the article on Pascal and Ultramontanism, of which I greatly admire the delicate and thorough handling. I wish I could send you something of any interest. But I am not well enough satisfied with the elementary work which I use as a text-book for my lower classes to offer it; and besides that I have published, since last in England, only memoirs of the botany of our new western regions, one volume of the botany of a Government South Sea Expedition, etc., all dreadfully dry and technical. I have been unusually busy this year, and am just now especially so, having to complete the preparation of nine lectures on Vegetation, which I am to give before the Smithsonian Institution at Washington next month. I do not much fancy popular lecturing, and do this only to please a very valued friend, Professor Henry, the secretary of this institution. This over, I shall return to my regular plodding work at home, with great satisfaction.