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CURRENT LITERATURE.
Algae
Hodgetts, William, J. A New Species of Spirogyra. Ann. Bot. Vol. XXXIV, 1020, 519—524.
The author gives a description of Spirogyra colligata, a new species from Worcestershire. The Alga presents many interesting features the most remarkable of which is the curious H shaped clamp connections between every pair of contiguous cells of the filament. A. detailed description of these clamp connections is given. The author thinks that these clamp connections are probably helpful in keeping the cells of the filament from breaking up into individual cells through excessive turgor pressure.
Certain individual cells of the filament show curious coiling which the author thinks may be useful in grappling the filaments together and thus aiding scalariform conjugation.
Three methods of conjugation were observed, (1) scalariform, (2) lateral and (3) terminal. Terminal conjugation, like lateral conjugation, takes place between two adjacent cells of a filament, but is brought about by the growing out of one extremity of the cell through the cross wall.
This terminal conjugation and the H shaped clamp connections are unique features and, according to the author, have not been observed in any other recorded species of Spirogyra. On account of the presence of these curious clamp connections and the variety of the modes of conjugation, the author considers the species to be the most highly evolved, if not the highest, of all the known species of Spirogyra.
M.O.P.
Physiology
Hill Leonard, M.B..F.R.S. The Growth of Seedlings in Wind. Boy. Soc. Proc. B. Vol. 02, p. 28.
The author conducted soma experiments to study the effect of wind on the germination and growth of seedlings. Mustard and cress seeds were grown on lamp wicks which were kept moist by their ends dipping in a basin of water. The seedlings were subjected to continuous wind from a blower fan which was running day and night with smoothness without stoppage during the whole course of the experiment which lasted many weeks. Seeds were also grown in still air as controls. The following results were recorded by the author. The drying of the upper surface of the seeds, even though the lower surface may be wet, was sufficient to stop the growth. Seeds which were grown in the wind were soon bent and twisted close to the wick very nearly horizontally. The wind exposed seedlings showed less growth in length, had more solids, less water, more ash, less protein and presumably
