I have this moment received your dear letter of the 4. instant, for the contents of which, I do indeed most truly thank you, but the most important point contained in it, Dr. Spencer is now at Paris quite well and happy. I have not heard of his supposed intentions to visit Russia, at least not until you have shown yourself in Europe for awhile. When will you come? I have not received one single letter from Dr. Morton since my return to England, and have been the more surprised at this, because I look upon _him_ as a worthy good man and as one whom, since my last visit to him, I cannot but consider as my friend. The return of Dr. Townsend to our happy land has filled me with joy, and trebly so when you tell me that he is as friendly disposed to me as I ever have been towards him. I congratulate you my dear friend, in the step which you have so kindly taken in my favour, by first selecting all such Bird-skins as you or Townsend have considered as new, and also in having given freedom to Dr. Morton to pay Dr. Townsend Fifty Dollars for the skins selected by you, under the _prudent_ considerations or restrictions talked of in your letter. May I receive all the Bird skins very soon, for depend upon it, now or never is for me the period to push on my publication. If I have any regret to express it is, that Townsend or Dr. Morton or yourself did not at once forward to me the _whole_ of the Bird skins brought latterly by Townsend, for I can assure you that it has become a matter of the _greatest niceity_ to distinguish the slight though _positive_ species lines of demarkation between our species of Birds—and if on this reaching you, the least doubt exists amongst yourselves respecting any one, why send it to me at once by the very earliest conveyance. If by New York, with letter to N. Berthoud to lose not a day, provided a packet, either to _Liverpool_ or London, is ready to sail! Had Townsend sent me the _whole_ of his disposible birds, I might now have perhaps been able to have mad[e] him a remittance in cash, which the single arrival of the German Naturalists, who are now in California may hereafter put an end to. Mention this to him, nay, shew him this letter if you please and assure him that I am willing to exert myself in his behalf. Indeed, I wish you to urge him in forwarding me either his own manuscripts or a copy of all such parts as appertain to Birds, as soon as possible, knowing (I think) that he will not undertake to publish them himself under his present (I am sorry to say) embarrassed pecuniary circumstances. Tell him that I want all about the habits of _any_ Birds which he has written upon, especially, however, those found from the beginning of his journeys until his return,