Page:The Zoologist, 3rd series, vol 2 (1878).djvu/283

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PROCEEDINGS OF SCIENTIFIC SOCIETIES.
259

of the zoœcium, — a view which may he regarded as too exclusive. He (Professor Allman) had, not long since, an opportunity of examining the remarkable organism known as Cyphonantes, a singular little free swimming animal found in the open sea. It is of a compressed pyramidal shape, its soft parts being included in a bivalve shell in the manner of certain Entomostraca. It has an organization of considerable complexity, being provided with a complete alimentary canal, with accessory glands, and with certain organs of extremely enigmatical import. Schneider attempted to show that Cyphonantes was the larva of a polyzoon, and he announced the startling fact that before its transformation into the adult, it becomes totally disorganised, every trace of structure disappearing, and the entire animal becoming reduced to a homogeneous mass of protoplasm ; and this, notwithstanding the complex structure of Cyphonantes, — more complex, indeed, than the German zoologist had imagined. It is in this homogeneous, structureless mass of protoplasm that the new polypide arises, and the whole becomes then metamorphosed into the form of the adult. Strange as this history may appear, it has been to a certain extent confirmed by the researches of Nitsch and Joliet, and he (the President) felt that, in the face of the evidence afforded by those researches, he would not be justified in still urging the objections which, chiefly on theoretical grounds, he had formerly offered. Finally, his address took up the question of "Indi- viduality," or the relation to the polyzoal colony, and he maintained, in the somewhat modified form resulting from the researches of Nitsch, the view which he had long ago brought forward, and which has since been generally accepted by recent investigators, namely, that the zoœcium or cell in which the polypide is lodged must be regarded as having a zooidal individuality, independently of the polypide, which has also a zooidal individuality of its own, and that the two thus form a compound element which becomes associated with similar ones in order to form the colony. This compound animal is thus composed of two zooidal individuals, — zoœcium and polypide ; on the zoœcium devolving the functions of sexual and non-sexual reproduc- tion, and on the polypide that of nutrition.

At the conclusion of his Address, Prof. Allman called attention to some living examples of Tree Frogs (Hyla arborea) which he had obtained in the South of Europe. Those now exhibited to the Fellows convincingly showed the remarkable change of colour which this species of Frog is known to possess, some of them being green, others bright blue. This change of hue is due to certain pigment-corpuscles, the precise nature of which Prof. Allman is at present engaged in investigating.

The Report on publications was read by the Secretary, and that on the balance-sheet by Dr. R.C.A. Prior. Afterwards the Treasurer (Dr. J. Gwyn Jeffreys) read his statement of the accounts, &c, of the past financial year, 1877. This showed a highly satisfactory result, a balance of £46 13s.