Page:The Zoologist, 3rd series, vol 1 (1877).djvu/329

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Annual General Meeting, Wednesday, May 24, 1877.—The customary Address on the occasion of the Anniversary was delivered by the President, Prof. Allman, F.R.S. He took as his subject, "Recent Researches among the Lower Sarcode Organisms," being a continuation of his Address of last year. He dwelt upon the important additions to our knowledge of these organisms due to the investigations of Archer, in our own country, and of Hertwig and Lesser, Franz Eilhard Schulze and Greeff, in Germany. The discovery of many new Monothalamic Rhizopods of fresh water, and the important additions made by the British and German investigators to our knowledge of their protoplasmic bodies, were brought in review before the meeting. These Monothalamic forms may be divided in accordance with the nature of their pseudopodia; in some these processes being short, thick, and finger-shaped (Lobosa); in others, long, slim and filiform (Filifera). The former were illustrated by Hyalosphenia, with its smooth, transparent shell, and of Quadrula, with beautifully sculptured shell; and the latter by Gromia, with very long filiform reticulated pseudopodia, and by Microgromia socialis, which has the curious habit of forming colonies by the association of numerous individuals which become united to one another by the mutual fusion of their pseudopodia. The remarkable form of reproduction discovered by Hertwig in Microgromia was also described. Hertwig had shown that in this Rhizopod the protoplasm divides by spontaneous fission into two segments, one of which remains in the shell, while the other forces its way out, assumes an oval shape, develops instead of pseudopodia two vibratile flagella, and becomes a free-swimming flagellate Zoospore, capable of ultimate development into the form of the adult. The very interesting discovery by Haeckel, that the contents of the so-called "yellow cells" of the Radiolaria become of a deep violet colour under the action of iodine, and are therefore mainly composed of starch, was also referred to among recent additions to our knowledge of the lower organisms. An account was then given of the remarkable and very significant researches of Messrs. Dallinger and Drysdale among the so-called "Monads"—microscopic organisms which become developed in putrefying solutions of organic matter, and which, in their ordinary and apparently adult state, swim about by the aid of vibratile flagella. These laborious and trustworthy investigators have shown that the flagellate Monads may acquire an amœboid condition, and move about by the aid of pseudopodia; that two such amœboid forms when they come in contact with