The impulse to microscopic research, that had led to the foundation of histology and embryology, had brought about a third great advance which had an important bearing on zoology. When we stroll along the beautiful shore of the Mediterranean at Naples to-day, with eyes bent on the blue surface from which Capri rises like a siren, and on the cloud-capped Vesuvius with its violet streaks of lava cutting across the green country, we notice in the foreground of the picture a stout building, with very large windows, planted with the boldness of a _parvenu_ amongst the foliage. It is the “Zoological Station,” built by Dohrn, a German zoologist, at the beginning of the seventies. Anton Dohrn was one of Haeckel’s first pupils, and was personally initiated by him into the study of marine life, at Heligoland in 1865. Zoologists who work in the station to-day find it very comfortable. Little steamers with dipping apparatus bring the inhabitants of the bay to them. There is a large aquarium at hand. You sit down to your microscope, and work. The material is “fresh to hand” every day. There are now many of these stations at well-exposed spots on the coast in various countries—sea-observatories, as it were, in which the student examines his marine objects much as the astronomer observes his planets and comets and double stars at night. To-day, when a young man is taking up zoology, and he is asked what university he is going to, he may say that he is going down to the coast, to Naples, to do practical work. When the long vacation comes, swarms of professors go from the inland towns to one or other seaside place, as far as the purse will take them. All this is a new thing under the sun. The zoologist of the olden days sat in his study at home. He caught and studied whatever was found in his own district. The rest came by post—skins, skeletons, amphibians and fishes in spirit, dried insects, hard shells of crustacea, mussels and snails of all sorts; but only the shells always, the hard, dry parts of star-fishes, sea-urchins, corals, &c. Animals of the rarest character were thrown away because they could not very well be preserved in spirit and sent from the North Sea or the Mediterranean to Professor Dry-as-dust. In this state of things the advance in microscopic work brought no advantage. But at last it dawned on students that the sea is the cradle of the animal world. Whole stems of animals flourished there, and there only. Every wave was full of innumerable microscopic creatures, of the most instructive forms. Amongst them were found the young embryonic forms of familiar animals. At last the cry, “To the sea,” was raised. The older professor of zoology had suffered from a kind of hydrophobia. It was not possible to teach very much at Berlin about the anatomy, histology, and embryology of the sea-urchin from a few dried flinty shells. At Würtzburg, animals were subtly discussed by men who had