When Charles Darwin went to Edinburgh, the university was not in one of its palmiest periods. The medical professors failed to attract him to their profession, and two years of Edinburgh satisfied him that medicine should not absorb him. With natural history the case was different. Its attractiveness for Darwin increased. He found congenial companionship in the Edinburgh Plinian Society, and Mr. W. F. Ainsworth relates (in _The Athenæum_, May 13, 1882) that Darwin and himself made frequent excursions on the shores of the Firth of Forth in pursuit of objects of natural history, sometimes visiting the coasts of Fifeshire, and sometimes the islands off the coast. On one occasion, accompanied by Dr. Greville, the botanist, they went to the Isle of May, and were both exceedingly amused at the effect produced upon the eminent author of the Scottish Cryptogamic Flora by the screeching of the kittiwakes and other water-fowl. He had actually to lie down on the greensward to enjoy his prolonged cachinnation. On another occasion the young naturalists were benighted on Inch Keith, but found refuge in the lighthouse. Darwin was now not merely a collector and exploring naturalist, but he observed biological facts of importance. On the 27th of March, 1827, he made a communication to the Plinian Society on the ova, or rather larvæ, of the Flustra or sea-mat, a member of the class Polyzoa, forming a continuous mat-like colony of thousands of organisms leading a joint-stock existence. He announced that he had discovered in these larvæ organs of locomotion, then so seldom, now so frequently, known to exist on such bodies. At the same time, he made known that the small black body which until that time had been mistaken for the young state of a species of seaweed, was in reality the egg of _Pontobdella muricata_, a sort of sea-leech. On the 3rd of April following, the discoverer exhibited specimens of the latter creature with eggs and young. In making these researches, Darwin was no doubt stimulated and aided by the teaching of Dr. Grant, afterwards Professor of Natural History at University College, London, who was then at Edinburgh, making discoveries in the structure of sponges. Professor Jameson, too, who was then forming his splendid museum of natural history, cannot fail to have influenced Darwin somewhat; and we find that the first lecture of the concluding portion of Jameson's zoological course, dealing with "The Philosophy of Zoology," had the suggestive title of "The Origin of the Species of Animals." Thus we must acknowledge that already at Edinburgh Darwin was fairly started in the paths of zoological inquiry, and the northern university must be admitted to share with Cambridge, the distinction of being the foster-parent of this giant-child.