Brown came to the museum this morning with a copy of a curious late paper of Schleiden (which I had seen before) on the Development of the Embryo, with a parcel of his own notes on the same subject made in 1810, 1812, 1815, etc., which did not altogether correspond. Brown thinks much of Schleiden as an observer. He read me many of his old notes, and the subject took him to speak of his discoveries with regard to the embryos of Pinus. To explain to me as he went on he drew the diagram on the inclosed slip of paper, and pointed out to me how to observe in our species of Pinus. This will refresh my memory as to all he told me, so pray keep it safely. There is much very curious matter now afloat about the process of impregnation and the early development of embryo, which I am accumulating, as much as I can, for future use. Pray tell Dr. Perrine that the gardeners and botanists here insist by acclamation almost that there is no such thing as acclimation in the vegetable kingdom. What a pickle the Linnæan Ascyrum is in! I wish I had room to tell you. TO MRS. TORREY. Tuesday morning, two o’clock A.M., March 14, 1839. I have just finished packing up, being about to start for Boulogne in steamboat at nine o’clock this morning, and I must now hastily close my letters. This, or rather yesterday, has been a busy day with me. I started in the morning to have a look at a few more things of Pursh’s at Lambert’s, but he kept me longer than I liked. He found somewhere a small parcel of plants collected by Eschscholz in Kotzebne’s voyage, who sent them to Lambert. Lambert gave me all the North American ones, few to be sure, but interesting. From Lambert’s I returned by way of the Horticultural Society, to bid good-by to Lindley and Bentham, but the latter insists upon coming up in the morning to my lodgings to see me off. I have made a fortunate acquisition for him. He told me he saw, a few days ago, at an auction some copies of Richard’s fine work on the Coniferæ, but an engagement at the time prevented him from staying to buy a copy of the work for himself, which he imagined would be sold cheap. Mr. Putnam found out who bought up these copies, and obtained one at nearly the price at which they were sold. I shall have the pleasure of presenting it to Bentham this morning when he calls. I went to the British Museum, worked hard until four o’clock; but was not able quite to finish, so I left my copy of Gronovius, in which I was making notes, with Mr. Bennett to keep for me until my return in the autumn, and took leave of Brown and Bennett. Went to Dr. Boott’s; saw Mrs. and Miss Boott, who insisted upon giving me a note of introduction to a friend of theirs in Florence; went to the City, dined with Putnam, down to Well-close Square, took my tea, and bid good-by to Ward and family, and Mr. Quekett.... TO THE MISSES TORREY. PARIS, March 18, 1839, Monday evening.