ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 603 



to catch the small protista which occur in masses during the summer, 

 and take the place of the diatoms which abound in spring. 



Another generally accepted theory is here contested. It has yet to 

 be proved that the tropical seas are poorer than the polar regions in 

 plankton, for it is possible that in the warmer seas there may be a large 

 number of the smallest organisms which have escaped the net* Indeed, 

 the author shows that the Coccolithophorideas abound in masses in the 

 upper layers of the warm oceans, and he thinks it probable that the rate 

 of reproduction is much greater in the tropics. 



The author then gives some interesting and important facts re* 

 garding the Coccolithophorideae and the formation of sediment in the 

 sea. These organisms, together with the Peridiniese and Diatoms, form 

 the most important elements of nutrition and sediment. 



In the third of the treatises mentioned the views of Brandt, Nathanson, 

 and Putter are very clearly stated, and criticisms are made by the autho 1 - 

 on certain points. 



The three papers in question are important contributions to the 

 literature of plankton study, and a good resume of them is given in 

 Hedwieria.* 



Phytoplankton of the West Indies.f — B. Schroder gives an 

 account of the phytoplankton collected at St. Thomas and the Tortuga 

 Islands. The phytoplankton was relatively small — 70 forms from 

 St. Thomas, mostly tropical surface forms. From Tortuga came a 

 much greater preponderance of microscopic zooplankton. Notes on 

 three species are given ; one of the species is new. 



Phytoplankton of the North Atlantic.:}: — W. Stiiwe publishes a 

 very full report of various collections of plankton, which were made at 

 the instigation of Professor Schutt, by captains of vessels crossing the 

 Atlantic. In particular, the collection of Captain Reinecke, made in 

 the Gulf-stream, the Canary, the North and South Equatorial, and the 

 Guinea currents, and in the Sargasso Sea, appears to have been very 

 valuable. The plankton is treated from a qualitative and a quantitative 

 point of view, and the author reports on each haul under both these 

 headings, illustrating the results in a table showing the relative 

 frequency of each species in each haul. The same detail is observed 

 in the presentation of the quantitative results, and this is followed by 

 some short critical notes, descriptions of new forms, and varieties ; and 

 finally there is a systematic list of all the species found, together with 

 their geographical distribution and a reference to already existing 

 figures. 



o' 



French Peridiniese. § — J. Pavillard publishes some supplementary 

 notes on the Peridinieae of the Gulf of Lyons and the Etang de Thau, 

 near Cette. Among the species recorded, the following are new to 

 science, and descriptions and figures of them are given — Gonyaulax 



* Hedwigia, xlviii. (1909) pp. 153-5 (Beibl.). 



t Ber. Deutsch. Bot. Gesell., xxvii. (1909) pp. 210-14. 



j Engler's Bot. Jahrb., xliii. (1909) pp. 225-302 (1 map and 2 pla.). 



§ Bull. Soc. Bot. France, lvi. (1909) pp. 277-84 (5 figs.). 



