Offers to send Ascidia specimens of Beagle voyage. Describes some of them.

Hopes THH will review his book [Living Cirripedia, vol. 1] which has been published for a year with no notice taken of it except briefly by Dana.

Discusses Limulus-like larva. "I have become a man of one idea.– cirripedes morning & night."

Asks THH question on flow of glaciers after ice has been fractured and fragmented.

CD had to leave Royal Society lecture [joint paper by THH and J. Tyndall, "On the structure and motions of glaciers", Philos. Trans. R. Soc. Lond. 147 (1857): 327–46] before the end because of headache.

THH’s catalogue [THH and R. Etheridge, A catalogue of the collection of fossils in the Museum of Practical Geology (1865), part published in 1857] best résumé he has seen of science of natural history. On classification he is not quite sure that he wholly goes along with THH. Encloses a few criticisms of THH’s preface.[enclosure survives as copy only].

Murray has sold out Origin; wants a new edition immediately.

Asks THH to check whether Geoffroy de St Hilaire is correct [form of name].

Would be grateful for THH’s impressions on the truth of natural selection.

Sends enclosure [unspecified].

Reminds THH to mention [German] translation [of Origin] when he writes to R. A. von Kölliker.