He misses society. "I often conjecture what will become of me; my wishes certainly would make me a country clergyman. – You expect sadly more than I shall ever do in Nat. Hist: I am only a sort of Jackall, a lions provider; but I wish I was sure there were lions enough."

Has collected a host of minute beetles, some reptiles, small quadrupeds, and fishes. Invertebrate marine animals are his delight. The pleasure of working with microscope ranks second only to geology.

Writes of his ride from Rio Negro to Bahia Blanca and Buenos Aires, which he undertook in order to learn the geology of the land, so full of bones of large extinct quadrupeds.