Palaeontologie. — Algae. 39 



tung erlangten sie als Fruchtbäume durch den Menschen. Ihre 

 frühzeitige spontane Einwanderung spricht dafür, dass sie durch 

 die Eiszeit wohl zum Rückzug gezwungen, aber nicht ganz aus 

 Mitteleuropa verdrängt waren. C. Schröter (Zürich). 



Fpitseh, F. E., and F., Rieh. Biology and Ecology of the 

 Algal Flora of Abbot's Pool, near Bristol. (Proc. Bristol 

 Nat. Soc. IL Pt. 2. p 27-54. iL 1909.) 



Samples were taken monthly during five years, the temperature 

 of air and water being noted, and these with rainfall statistics give 

 data for comparison of the algal flora with the environment. The 

 normal annual cycle of pond-life resolves itself into four phases: 

 Winter (Dec— Feb.) with abundance of free Diatoms; spring-phase 

 with Spirogyra dominant; summer, a relatively inactive phase, 

 with Cladophora dominant, but restricted in its activity by abun- 

 dance of epiphytes, chiefly Diatoms {Synedra, Cocconeis, etc.); 

 autumn with renewed activity of all forms. The periodicity, ecology 

 and reproduction of the dominant forms and of subsidiary forms 

 {Oedogoyiium , Mougeotia, and Cyanophyceae) are dealt with in detail 

 for which the original paper should be referred to. The whole algal 

 Vegetation is regarded as an association or formation made up of 

 certain groups or sub-associations which reach their maximum 

 development at different periods of the year, and each one passes 

 through its annual cycle relatively independent of the other sub- 

 associations. The Spirogyra sub-association has its maximum period 

 of abundance and zygospore formation in the spring-phase, and 

 variations observed in different years are ascribed to water-conditions 

 rather than to competition of other forms. The genus Cladophora 

 shows a maximum in winter and diminishes throughout the year, 

 the reduction coinciding with a summer increase ofepiphytic Diatoms, 

 hence this is regarded as a competitive sub-association. The free- 

 living Diatoms constitute another sub-association. The factors operating 

 on the algal Vegetation are resolved into seasonal, irregulär, and 

 correlated. The seasonal factors are changes in concentration of 

 the water, in temperature, in quantity of dissolved gases and the 

 amount of organic matter, and in light-intensity. The irregulär 

 factors are due to abnormalities in temperature, rainfall and sun- 

 shine. The competition between Cladophora and its epiphytes is an 

 example of correlated factors. W. G. Smith. 



Laing, R. M., The Marine Algae of the Subantarctic 

 Islands of iVew Zealand. (C. Chilton. The Subantarctic 

 Islands of New Zealand. Wellington, N.Z. p. 493—527. 4 pl. 1909.) 



The author gives an account of the algae collected during the 

 "Hinemoa" expedition to the Islands lying South of New Zealand, 

 namely, The Snares, and Auckland, Campbell, Antipodes and 

 Macquarie Islands. He enumerates 89 species and describes two 

 new varieties, Ceramiutn stichidiosian J. Ag. var. Smithii and var. 

 Scoptclorum. Critical notes are appended to many of the species. 



E. S. Gepp. 



Tpaunsteiner, M., und J. Verzeichnis der bisher in Kitz- 

 bühel und Umgebung aufgefunden Arten der Gattung 



