Algae. — Eum5'^cetes. 111 



Rigg, G. C, Is Salinity a factor in the distribution of 

 Nereocystis Liietkiana? (Bull. Torrej' Bot. Cl. XL. p. 237—242. 

 May 1913.) 

 The conclusion is reached that kelps are to be looked for on 

 the northwest Coast only vvhere the water has practically the nor- 

 mal salinity of seawater. Trelease. 



Sutherland, G. K., Seme methods of Plankton investiga- 

 tion. (Jour. of Ecology. I. 3. p. 166. 5 figs. 1913.) 



A suramary of recent methods including illustrated descriptions 

 of the Nansen, Hensen, and Apstein nets, and the Kolkwitz 

 metal sieve and plankton Chamber. Methods of preservation, coun- 

 ting and Separation are also given. W. G. Smith. 



Williams, J.Lloyd, The Zoospores ofthe Laminariaceae and 

 their Germination. (Report 28th Meeting ßrit. Assoc. Advanc. 

 Sei. (Dundee 1912.) p. 685—686. London 1913.) 



In reply to a paper by G. H. Drew (Annais of Botany XXIV. 

 p. 177. 1910.) in which he claimed that the zoospores oi Laminaria 

 are gametes and that he had observed their fusion, J. Lloyd Wil- 

 liams Shows that the colourless fusing organisms were Monads, and 

 not zoospores of Laminnria. The real pear-shaped zoospores of La- 

 minaria, with their prominent bent chromoplasts, never fuse. When 

 they settle down they become spherical and are invested with a 

 wall, and the curved chromoplast divides at the bent. A long tube 

 grows out at one side of the spherical spore case; and into this 

 pass the two chloroplasts and most of the other contents. But the 

 nucleus remains behind and divides; the two daughter-nuclei then 

 move into the tube. An enlargement is formed at the distal end, 

 and, becoming separated off by a transverse wall, is found to con- 

 tain the chloroplasts, one of the nuclei and most of the other cell 

 Contents. The second nucleus remains in the tube and degenerates. 

 The new cell grows, and by cell division may form a simple or 

 branched protonema, which may rest for months or vsxz-y give rise 

 to a germling in a fortnight. In the curious process of germination , 

 a cell of the protonema becomes pear-shaped, with a thick mucila- 

 ginous wall at the pointed end. At this end the cell contents are 

 forced out still enclosed in a thin pellicle. The escaped cell divides; 

 and the basal cell of the row puts out one or more rhizoids, which 

 offen grow along the outside of the empty cell — not inside as 

 figured by Drew. Williams examined Laniinaria, Alaria and Chorda, 

 and found the same process in each. There is no doubt that the 

 swarming bodies are asexual. A. and E. S. Gepp. 



Brierly, W. B., The Structure and Life-History of Lepto- 

 sphaeria Lemmieae (Cohn). (Mem. Proc. Manchester Lit. Phil. Soc. 

 LVII. 2. NO. 8. p. 24. 2 pl. June 1913.) 



The paper gives a detailed account of the Pyrenomycete inha- 

 biting the Red Alga Lemanea ßuviatüis. 



After dealing with the distribution of the mycelium in the 

 thallus the author passes on to the archicarps observed hy Woro- 

 nin. Judging by the nuclear phenomena as seen in microtome 



