602 SUMMARY OF CURRENT RESEARCHES RELATING TO 



northern part of the Adriatic (the Gulf of Trieste) shows the poore-t 

 number of species. This is caused by the greater inflow of fresh water 

 and the fouling from the harbour of Trieste. For this reason there 

 exists here a foul-water flora with few species but great development. 

 Outside the Gulf in pure water the number of the species increases 

 immediately, and a similar increase takes place at Quarnero where the 

 typical blue water of Dalmatia begins. The greatest depths at which 

 alga- are found is about 140 in., where islands of alga? occur on the 

 barren mud. Summer and winter are deep times for the algae. They 

 show a more lively growth in spring than in autumn. The biological 

 conditions of the plankton are in many respects parallel to those of the 

 Iniithos. Both in their rise and fall they are almost in agreement, and 

 in the limits of their distribution. It is possible to establish a vertical 

 stratification of the plankton, even though a number of surface specie- 

 occur in equal quantity down to 200 m. 



Trachelomonas.* — G. I. Piayfair publishes an account of the species 

 and varieties found in New South Wales during the past seven years, in 

 the two districts of Sydney and Lismore. The waters there are very rich 

 in forms of the genus, and exhibit a great variety of types. Ground- 

 gatherings out of swampy places were found to be best, those out of 

 weeds less good. One hundred and four species and varieties are recorded , 

 many of them new to science. The author points out that the species 

 a it, of course, conventional ones for purposes of classification. Of 

 biological species in Trachelomonas he only recognizes two — (1) com- 

 prising all the rounded forms, (2) the tailed (stipitate) forms ; and of 

 these two even the latter is of doubtful distinctness. The reproduction 

 and the composition of the lorica are shortly discussed. 



German Diatoms. f — F. Hustedt reports on Bacillariales from the 

 Sudetic Mountains and neighbouring regions of the Oder valley. 

 Thirty-nine genera, containing 259 species, are recorded. Critical re- 

 marks are made on the various species, and data are given concerning: 

 the vertical and horizontal distribution. 



Diatoms of Steiermark.J — W. Bouvier publishes the first account 

 of the diatoms of Steiermark. He deals with the Fragilarioideae, 

 Achnanthoidese, Naviculoideas, and Surirelloidese. Many forms are de- 

 scribed and figured, but no names are given to them, although they are 

 in all probability new. Great plasticity of form was found in Geratoneis 

 arms Kutz., Navicula iridis Ehr., Pinnularia mesolepta Ehr., P. sub- 

 solar is Gruu., and P. viridis Ehr. 



Nuclear Division in Vaucheria.§ — L. Kurssanow writes a full 

 account of the nuclear division in Vaucheria, the species examined being 



* Proc. Liunean Soc. New South Wales, xl. (1915) pp. 1-41 (5 pis. and figs.). 



t Arch. Hydrobiol. u. Planktouk., x. (1914) pp. 1-128 (2 pis.) See also Bot. 

 Centralbl., cxxix. (1915) p. 250. 



% Jahresb. k.k. Staatsgymn. Leoben, xvii. (1915) pp. 3-16 (3 pis.). See also 

 Bot. Centralbl., cxxix. (1915) p. 249. 



§ Biol. Zeitschr. Moscow, ii. (1912) pp. 13-27 (1 pi.). See also Bot. Centralbl., 

 cxxix. (1915) p. 133. 



