To J. D. Hooker   [3–17 February 1844]

My dear Sir

I write a line merely to acknowledge & thank you for your long & to me most agreeable letter & to tell you that I am in communication with Ehrenberg to find out more definitely, what objects he wishes for, and I will let you know in time for you to send me any likely objects to contain infusoria. I know thus far that his chief present object is the geographical range of infusoria, so that I cannot doubt, of all things, he would most value specimens from the Antarctic regions.—

Would not floating sea-weed probably still contain some attached to it— I am astonished at your description of the number of Infusoria in the far-antarctic seas.—

Once again I thank you for your letter, & I can hardly tell you, how much all your facts & opinions interest me.—

In Haste | mp; I can hardly tell you, how much all your facts & opinions interest me.—

In Haste | Believe me | Most truly yours | C. Darwin

PS. | D^r. Dieffenbach, the New Zealand traveller,¹ (who has translated my Journal into German)² (& I must with unpardonable vanity boast to you, that it was at the instigation of Liebig³ & Humboldt⁴ ) wrote to me about the Infusoria at the request of Ehrenberg & to him I have written some further questions.—

I cannot doubt, Ehrenberg would value all your notes & drawings whether imperfect or perfect.