My dear Sir James Ross

I am going to beg a favour of you, which your taste for Natural History, will, I hope, lead you to grant; it is to collect for me, during your ensuing expedition¹ & preserve in spirits the northern species of Cirripedia or Barnacles, noting the latitude under which found, & whether the coast-rocks are abundantly covered. Perhaps the floating timber may have some of the pedunculated division or Lepas.— I am now at work, & shall be for the next two years, on a Monograph on the Cirripedia; & the above specimens would be particularly valuable to me. I do not suppose that your expedition, considering its noble object, will afford you much opportunity for collecting, but Barnacles are so easily scraped off the rocks & put into spirits, that it would cause you but little trouble. Different species often resemble each other rather closely externally. The only care required is that some of the specimens should have their bases perfect & that a few young individuals sh^d. be collected.

I hope, if it be in your power, that you will thus far oblige me, & place this letter amongst your Memoranda.

I do not know, who commands the first ship;² if he has any taste for Nat. Hist, would you object to ask him to collect some specimens for me in a dry state, (marking the locality) if he object to the trouble of placing them in spirits.—

I trust to your kindness to forgive my asking this favour, & pray believe me, with every good wish for your success in your arduous voyage | Yours very faithfully | C. Darwin To Capt. Sir J. Ross.—