CRYPTOGAMIA. 395
Luders. — EJnige Bemcrkungcn iiber Diatomeen-Cysten unci Diato- meen-Schwarmsporen von Joh. E. Luders. Botanische Zeitung, 30 November, 1860.
The author, after referring to the observations of Smith (Bri- tish Diatomacea?, Vol. 2, p. xv.) and of Hofrneister (Bericht iiber die Verhandl. der Konigl. Sachs. Gesellschaft der Wissensch. zu Leipzig, 1S54, i. p. 28), and to the remarks of De Bary in the Supplement to the Bot. Zeitung for 1858 (p. 62) gives an account of his own observations upon Synedra radians, Cocconema, and Gromphonema, which he says show clearly that the cysts are formed by Amoeba?. He also describes the production of infu- soria in the cells of Podosphenia Lyngbyei, Achnanthes longipes, Melosira Borrerii, Amphora ovalis, Gomphonema constricta, acu- minata and intricata. He considers it probable that these infu- soria or some allied productions have given rise to the notion of the existence of zoospores in the Diatomacea?, but adds that he has never yet succeeded in finding true zoospores in that tribe of plants.
Norman. — On some undescribed species of Diatomaceae by Greorge Norman, Esq., of Hull. Quart. Journ. of Mic. Sc. New Series, Part 1.
Prixgsheim. — Nachtrag zur Kritik und Greschichte der Untersuch- ungen iiber das Algengeschlecht von N. Pringsheim ; Jahrbiicher fiir wissenschaftliche Botanik, Band ii. Drittes Heft, p. 470.
This paper relates to the reproductive process in Vaucheria, and is devoted to a refutation of Dr. Karsten's objections to the author's published observations on that phenomenon.
Pritchard. — A History of Infusoria, including the Desmidiacea? and DiatomaceaB, &c. By Andrew Pritchard, M.E.I. Fourth edition, enlarged and revised by J. T. Arlidge, W. Archer, J. Ealfs, W. C. Williamson, and the author. 40 plates, pp. 968.
Eabexhorst, Dr. L. — Die Algen Sachsens, resp. Mittel-Europa's. Unter Mirwirkg. der H. H. Ardissone, de Bary, Bulnheim, etc. gesammelt u. hrsg. Decade 97-100. gr. 8. (a 10 Bl. m. aufgekleb- ten Pflanzen u. Alphabet. Verzeichniss 16 S.) Dresden, 1860, (am Ende.) cart.
Eeixice^;, E. — Die Bewegung der Oscillarien besonders der Spiru- lina. Beitrage zur neuern Mikroskopie, zweiter Heft. 8vo. Dresden.
The first part of this paper contains some remarks upon the movements of the Oscillariae, with reference to the observations of Adanson, Brown, Saussure, Karsten, Mayer, and d'Alquen ; but the principal portion is devoted to the author's observations on the movements of a new species of Spirulina (Spirulina gra- cillima, Eabenhorst, Algen Sachsens, resp. Mittel-Europas, No. 895). He gives, as the result of his observations, the following facts : that in this species the spiral is sometimes left- sometimes right-handed ; that each spiral can revolve on its axi*, either to
