ZOOLOGY AND BOTANY, MICKOSCOPY, ETC. 581 



taken by the International Commission for the exploration of the sea. 

 The region explored includes the Arctic, North Atlantic, Norwegian 

 Sea, North Sea, the Channel, Skager-Rak, Cattegat, the Sound, Danish 

 Sea, Baltic, Finland Gulf, and Gulf of Bothnia. 



Phytoplankton of Temperate Seas.* — B. Schroder gives a pre- 

 liminary account of the characteristics of the phytoplankton of temperate 

 waters, being the result of investigations by himself and others. He 

 regards it as pre-eminently " polymiktes " plankton, for it consists 

 almost entirely of many species which are represented by but few 

 individuals ; it rarely occurs that one species is largely predominant or 

 forms great masses. As an instance of this variety of species in tem- 

 perate waters, the author points out that while his material from the 

 Indian Ocean showed 118 species, that from Japanese waters contained 

 147. Special cases are quoted in which certain species were found to 

 predominate : Chcetoceras Schiittii Cleve in the Bay of Naples in autumn, 

 a certain diatom which formed slimy masses at Triest, Chcetoceras in the 

 same locality, Ceratium volans Cleve in the Indian Ocean, etc. Lists 

 are given of the principal species characteristic of (a) the warm Atlantic 

 and Mediterranean ; (b) the Indo-Malay Sea ; (c) West Pacific (South 

 and East China Sea and Japanese waters). It is noted that cold water 

 species vary their form in temperate waters, and examples of this change 

 are given. 



Baltic Benthos and Plankton.t — H. Fraude divides his subject 

 into two parts, a general and a special part. In the first he treats of the 

 region studied, with its physico-chemical and biological properties, the 

 phytoplankton of the Baltic, and the researches already made there. In 

 the special part he deals with the first Holsatian expedition in 1887, 

 with others by Cleve and Aurivillius in 1896, by Schtitt in 1895, by 

 Appstein in 1889, the second Holsatian expedition in 1901, and with his 

 own personal collections. In the 36 plates the algas are figured in 

 systematic order. 



Plankton of Lake Worth in Carinthia.^: — K. v. Keissler continues 

 his reports on the plankton of Carinthian lakes, and in the present paper 

 enumerates the species found between March and September 1905 in 

 Lake Worth. To each species is appended a note on its seasonal dis- 

 tribution, and the list is also summarised in tabular form. Ceratium 

 plays but a small part in the composition of the plankton, while Lyngbya 

 limtietica Lemm. is well represented in August and September. Clathro- 

 cystis is also not uncommon in this lake, though rare in other Austrian 

 Alpine lakes ; it is common in North Germany. Raphidium and 

 Richteriella are also recorded. The species of Lake Worth are compared 

 with those of Lake Ossiach and the Millstatter lake, showing that the 

 differences are not inconsiderable. 



Bianchi, F.— Ricerche su un laghetto alpino (II Lago Deglio). (Researches on a 

 small Alpine lake, Lago Deglio.) 



Rivista Geograf. ital. xiii. (1906) p. 15 (figs.). 



* Ber. Deutsch. Bot. Gesell., xxiv. (1906) pp. 260-3. 



t Jahresb. Geogr. Gesell. Greifswald, x. (1906) 125 pp., 36 pis., 1 map. 



% Oesterr. Bot. Zeit., lvi. (1906) pp. 195-202. 



