thinning out of, [217]
how formed, [218]
summary of conclusions on the rate of formation of the, [221]
Seebohm, Mr., on Parus palustris, [65]
on Emberiza schœniclus, [66]
on snow in Siberia, [166]
on birds of Japan, [396]
Seeds, dispersal of, [257]
carried by birds, [258]