386 SUMMARY OF CURRENT RESEARCHES RELATING TO 



from Ducharfcre, in L 877, up to bhe great work of Oltmanns, in L904. 

 EEe is of opinion that too much Btress has been laid by some botanists 

 on bhe coloration of algae, and points Out instances where this lias led 

 io the absurdity of placing certain genera sometimes among the Rho- 

 dophyceae and sometimes in Cyanophyceae. He shows the greater 

 value iii classification of such characters as are furnished by structure or 

 general methods of reproduction for the division into large systematic 

 groups ; and for the secondary groups the peculiarities offered by the 

 different modes of multiplication, the reproductive organs, or, if acces- 

 sary, certain details of the thallus in connexion with the biological con- 

 ditions of their existence. The Characea? are of course definitely excluded 

 from the algae, and their connexion with the Coleochaetaceae, asserted 

 by some authors, is declared to be illusory. The author groups the 

 a Igae as follows : — 1. Florideae. 2. 'Fucaceae. ■). Confervae, including 

 (Edogoniales, Chaetophorales, Chroolepoidales, Ulvales, Schizogoniales, 

 Cladophorales, and Protococcoideae. 4. Siphoneae, divided into Bryo- 

 psidae, Codieae, and Vaucherieae. 5. Conjugatae, including Zygnemeae, 

 Desmidieae, and Bacillarieae. 6. Myxophyceae. All these groups are of 

 equal value. 



Epiphytes of the Laminarise.* — F. Tobler publishes studies on the 

 morphology and biology of the Laminarieae. He finds that the epiphyte- 

 flora is formed of small annuals, and that the number of these on plants 

 of Laminaria is a considerable factor in the enumeration of local species. 

 They disregard the ordinary zonal limits and other external conditions, 

 being dependent oidy on the main requirement of a suitable host, which 

 allows of points to which they can attach themselves. Wounds in the 

 host-plant provide suitable points for the starting of the epiphyte. Some 

 of these may be regarded as semi-parasites and even entire parasites. 



Algological Notes.j — Gr. S. West begins a series of notes on fresh- 

 water algae, which will include critical remarks upon little-known species, 

 discussions upon the validity of certain species, and the systematic position 

 of others, as well as short reports on small collections from various parts 

 of the world. The first of these notes contaius a list of thirty-three 

 species of algae collected from running water near Rivadeo, in north- 

 west Spain, by W. Fawcett in 1909. Most of the species were diatoms. 

 In the second note the author describes a diatomaceous earth from Lewis. 

 Outer Hebrides. It is fairly pure and of fresh-water origin, consisting 

 of a number of species, two of which stand out conspicuously from the 

 rest. viz. Suri/rella robusta Ehr. and Navicula nobitis Ehr. var. Dactylus 

 V. Hcurck. A list of the species is given. The third note contains re- 

 marks on twelve new or rare British algae, among which is a new species, 

 Anlcistrodesmus spirotsenia. In the fourth note the author discusses the 

 genera Dvplochsete Collins and Polychaetophora W. and G. S. West. He 

 gives his reasons for separating his own species, P. simplex, from that 

 genus, and making it the type of a new genus, OJigocheetophora. The 

 differences between the genera are pointed out. 



" Bot. Jahrl). f. System. Pflanzengesch. u. Pflanzengeogr., xliv. (1909) pp. 51-90. 

 See also Centralbl. Bakt. Parasitenk. u. Infekt., 2te Abt. xxix. (1911) p. 147. 

 t Journ. Bot., xlix. (1911) pp. 82-9 (figs, in text). 



