Responds to comments on geology of Florida.

Discusses coral reefs and paper by John Murray ["On the structure and origin of coral reefs and islands", Proc. R. Soc. Edinburgh 10 (1880): 505–18].

Comments on AA’s paper ["Paleontological and embryological development", Proc. Am. Assoc. Adv. Sci. 29 (1880): 389–414].

Thanks AA for letter on coral reefs. "I used to think … that areas of elevation and of subsidence must – as a general rule be separated by a single great line of fissure, or rather of several".

Suggests that AA urge again his views on reappearance of old characters.