extinction has been due to the action of analogous & equally imperfectly known causes, as those which make. Dasypus gigas uncommon.— or one species less common than others.— or one monkey than others. or still better one Sloth than other.— This is legitimate course of argument, for in know cases of extinction. (I after Lyell, thinking that men act like other animals) this is the cause.— in S. America & Europe we see the change from all recent to some extinct is made by change in proportional numbers. Some becoming rare.^t1

Scientific Practice: theoretical statement; note refers to a person; reaction to idea; speculation; reasoning from theory; metaphysical implications
Physical Characteristics: wove paper; off-white; embossing: crown; (partial wmk); folded

^t1 Some becoming rare] added in ink

Transcription and apparatus copyright the American Museum of Natural History