ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 601 



species chosen were Chlorella profothecoit/es Kriiger, Stichococcus sp., 

 two undetermined species of Chlorella^ and two others. All were culti- 

 vated on grape-sugar-peptone-ai,^ar, and injections were made into 

 rabbits. The results of the serum of the " Alge-Berlin " were very 

 different on different alg^. In Stichococcus and in Chlorella ])rotothe- 

 rouks there was no agglutination. Stichococcus-serum. acted only on 

 Stichococcus. It is suggested that such serological experiments may 

 supersede the purely descriptive method in determining species. 



Fresh-water Algse of Middle Europe.* — A. Pascher is editing a 

 series of monographs by experts on the fresh-water flora of Germany, 

 Austria and Switzerland. Some of the parts have appeared, namely, 

 Flagellat^e by Pascher and Lemmermann ; Dinoflagellat^ by Schilling ; 

 Zygnemales by Borge and Pascher ; and Bacillariales by von Schonfeldt. 

 Two great features of the series are the text figures which illustrate the 

 principal characters of almost every species ; and the keys for the deter- 

 mination of species. For each of the larger groups there is given, 

 besides the systematic part, a general account dealing with the morpho- 

 logy, development, biology, and methods of examination, culture, and 

 preparation. The monographs are no mere compilation, but contain 

 new and original work. 



Periodicity of Plankton in the Western Mediterranean.!— M. J. 

 Pavillard reports on the periodic evolution of phytoplankton in the 

 western Mediteranean. The enormous quantitative variations of the 

 North Atlantic and of the Lake of Thau do not occur. The almost 

 total disappearance of phytoplankton in winter does not take place as in 

 the Xorth Atlantic : on the contrary, the flora attains its maximum at 

 that season. In November are found 40 to 50 species of Peridiniefe, 

 about 30 species of diatoms, Thallassiothrix Frauenfeldi being dominant, 

 etc. In February T. long issima and Rhizosolenia Te^iiperei occur. March 

 and April are not a rich period. In May and June conditions improve. 

 Chsetoceros anastomosans predominates. In July, certain diatoms may 

 increase. In August, given a sufficiently high temperature, the diatoms 

 l»ecome rare and Peridiniese preponderate, but the total density is small. 

 This condition continues more or less late into the autumn. Diatoms 

 and Peridiniese increase afresh in October, and the cycle recommences. 



Flora of the Lochseen.J— A. Kurz writes a hydrobiological study of 

 the Lochseen and their environs. These lakes are remains of the old 

 course of the Rhine between Pheineer and Bregenz, and the lower of 

 the two lakes communicates in summer with the lake of Constance. 

 The area was divided into regions and the plant-associations carefully 

 examined. The microscopic flora at the edge of the lakes, the benthos, 

 consists principally of diatoms, of which 7:5 species were determined. 



* Die Siisswasser-flora Deutschlands, Oesterreichs u. der Schweiz, A. Pascher 

 ed. Jena : Gustav Fischer (1913) 16 parts. 



t Assoc. Fran(?aise Avanc. Sci., 41e Sess., Nimes, 1912 (1913) pp. 395-7. See 

 also Bot. Centralbl., cxxiii. (1913) p. 326. 



X Arch. f. HydrobioL, viii. (1912) 140 pp. (4 pis.). See also Bot. Centralbl., 

 cxxiii. (1913) p. 301. 



