Discusses the flora of Porto Santo in relation to that of Madeira. While these islands have some 20 endemic species in common, there are 7 or 8 species endemic to Porto Santo alone, and 25 common to Porto Santo and Europe that are not found on Madeira. Believes the great difference in soil and climate is enough to explain this: plants common on one island cannot be made to grow on the other. Believes J. D. Hooker has underestimated the number of species endemic to Madeira. There are some remarkable endemic species of common plants in the Dezertas.

The eel is the only freshwater fish on Porto Santo and Madeira.

To cast doubt on CD’s view that volcanic action is associated with elevation of land, CL suggests that local oscillations in strata underlying volcanoes could also explain how active volcanoes have uplifted fossil deposits of marine shells. Overall he is more inclined to believe that recent volcanoes belong to areas of subsidence rather than of elevation.