Page:The Zoologist, 3rd series, vol 1 (1877).djvu/330

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304
THE ZOOLOGIST.

one another become instantly blended together at the point of contact; that this blending becomes more and more intimate, until the two individuals become completely fused together, when their mingled protoplasm assumes the form of a spherical sac filled with particles of immeasurable minuteness. These particles are germs destined for the reproduction of the individual. Their form can be demonstrated only by the highest powers of the microscope, and by following them by means of a 150 of an inch object-glass. Messrs. Dallinger and Drysdale were enabled to trace their gradual development into the form of the adult. They further proved the remarkable and unexpected fact that these minute germs may be subjected to a temperature of 258° to 300° Fahr. without losing their vitality and power of development—a fact of vast significance in its bearing on the experiments connected with the question of spontaneous generation. Finally, attention was drawn to the quite recent discovery of Hertwig and F.E. Schulze of a nucleus in the Foraminifera. By this discovery their true systematic position can now be assigned to the Foraminifera, which must accordingly be removed from the region of Cytodes, or non-nucleated protoplasmic masses, to which they had been hitherto relegated, and placed on a much higher stage in the great division of the Rhizopoda. Resting on these facts, F.E. Schulze has attempted to represent, by the aid of a genealogical tree, the mutual affinities and derivation from one another of the various members of the Rhizopoda. The base of the tree, where its stem is as yet undivided, consists of the primitive forms—mere non-nucleated Cytodes, represented by Haeckel's Monera (Protogenes, Protamœba, &c.). From these, by the differentiation of a nucleus in their protoplasm, are evolved the nucleated forms (Amœba, fresh-water Monothalamia, Foraminifera, Heliozoa, &c.), which constitute the subdivisions into which the stem branches off. These repeat the various modifications of pseudopodia (lobose, filiform, &c.), which had already existed in the primitive forms, and which they thus derive by inheritance from their non-nucleated progenitors. Finally, through the branch of the Heliozoa, we are conducted to the ultimate twigs formed by the families of the Radiolaria, in which we find not only nuclei but a "central capsule" indicating the highest grade of differentiation attained by any of the group.

Among purely business matters, the Treasurer (Mr. J. Gwyn Jeffreys, F.R.S.) read his statement of the accounts, &c., of the past financial year. His report was very favourable, showing not only that the Society was gaining ground as to numbers and means, but extending its influence and usefulness in publications, valuable additions to the Library, &c. The handsome donation of £500 of the late Mr. Charles Lambert was duly announced and thanks accorded. During the past year twelve Fellows and five Foreign Members died; and forty-three Fellows, three Foreign Members, and one Associate had been elected.