588 SUMMARY OF CURRENT RESEARCHES RELATISTG TO 



Fresh-water Algse of Schleswig-Holstein.* — W. Heeriug publishes 

 the first part of a flora of the fresh-water algge of Schleswig-Holstein and 

 the neighbouring towns of Hamburg anclLiibeck, and of the principality 

 of Ltibeck. Keys to the species of each genus are given, and diagnoses 

 of the species are appended to each record. Professor Hornfeld has 

 worked out the Desnoids. This, the first part of the book, contains the 

 introduction, in which the author gives the history of his collections and 

 studies for seven years in all parts of the province ; an account of 

 previous work ; examination and preservation of the material ; systematic 

 treatment of fresh-water algse in general and that adopted in this flora ; 

 measurements ; and general literature. Then the author passes to a 

 treatment of the Heterokontffi. Future parts of the work will deal with 

 Chlorophycete, Conjugate, Phasophyceas, Ehodophyceae, Cyanophyceje, 

 and BaciUariacese. The Characeee and Flagellatfe will not be included. 



Algge of Brandenburg.f — E. Lemmermann describes Gomjaulax 

 paJustris, a new species of fresh-water Peridiniea^. He also enumerates 

 all the species of GonyauJax, giving the synonyms, distribution, and 

 references to literature ; and appends a key for their determination. 

 Two of the 17 species occur in fresh-watei', -t in brackish-water, and 

 most of them in the warmer seas, 2 only being being decidedly northern 

 forms. The most widely distributed species is G. polygramma. 



Algse of the Danube at Vienna. |— J. Brunnthaler gives the results 

 of his examination of the alg« and Schizophycete collected in tlie waters 

 of the " Old Danube " near Vienna, and divides his remarks into two 

 sections, a general and a special part. In the first section he deals with 

 the biological conditions of the water, giving a map of the district which 

 shows the present river bed and the adjacent stretch of the so-called 

 " Old Danube." He discusses the temperature, transparency and colour 

 of the water, and mentions the phanerogamic plants growing there. 

 This is followed by an account of the plankton, presented also in the 

 form of tables ; and critical notes are given of some of the species which 

 constitute the phytoplankton, notably Geratium hirundinella. Twenty- 

 one figures show seasonal variations which occur in this species. The 

 flora of the river bank (benthos) is described, and a table shows the 

 periodicity of certain groups. In the second or special part of the paper, 

 all the algffi found are enumerated in systematic order. 



AlgSB of the Prague Water Supply.§— F. Ruttner has carefully 

 examined microscopically the water-supply of Prague, which contains a 

 , large percentage of organic matter. He gives a brief resume of investi- 

 gations of the supplies of other towns, and of his methods employed for 

 catching the organisms. He employed a filter of white tanned goat- 

 leather, after eliminating the coarser organisms with a straining of the 

 finest miller's silk. The proportion of organisms to a given volume of 

 water was estimated by careful counting under the Microscope. The 



* Jahrb. Hamburg Wiss. Anst., xxiii. (1905); Beih. 3 'Hamburg, 1906) pp. 

 59-150. t Beih. Bot. Centralbl., xxi. 2 (1907) pp. 296-300 (figs.). 



X Verb. k.k. Zool. Bot. Wien, Ivii. (1907) pp. 170-223. 



§ Arcbiv Nat. Land. Bobm., Prag, xiii. (1906) 47 pp. See also Bot. Zeit., 

 Ixv. 2 (1907) p. 227. 



