To Wilhelm Bernhard Rudolph Hadrian Dunker 5 April 
Down Farnborough Kent
At last I am able to return you your valuable specimens, & those belonging to Mess. Roemer Philippi & Koch.1 Pray accept my most cordial thanks for your great kindness & communicate the same to the above three distinguished naturalists. When you return the specimens, will you be so good as to present each of the above gentlemen with a copy of my small Monograph.2 —with which I am not well satisfied, though I have done it as well as I could.—
Pray believe me with much respect, | Yours much obliged | C. Darwin
Returns fossil cirripede specimens to WD, Friedrich Adolph Roemer, R. A. Philippi, and F. C. L. Koch.