, pre-adamite tortoises, resembling floating islands. Over the dimly lighted strand there trod the huge mammals of the first ages of the world, the

Leptotherium

(slender beast), found in the caverns of Brazil; the

Merycotherium

(ruminating beast), found in the “drift” of ice-clad Siberia. Farther on, the pachydermatous

Lophiodon