4o4 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Step han i, F. — Species Hepaticarum. (Species of Hepaticse.) 

 [Continuation of monograph of Plagiochila.~] 



Bull. Herb. Bois, ser. 2, iv. (1904) pp. 345-61. 



Tokka, V. — Bryum uliginosum Br. et Sch. Alg. Bot. Zeitsehr., 1904, pp. 84-5. 



T release, W. — Alaskan species of Sphagnum. 



[List of 22 species with 19 varieties ; two species are new to North America.] 



Harriman Alaska Exped., v. 1904, pp. 329-337. 



Z schacke, W. — Weitere neue Moosfunde aus Anhalt. (Further new moss records 

 for Anhalt.) Deutsch. Bot. Monatsschr., xxii. (1904) pp. 3-6. 



Thallophyta. 



Algse. 



Plankton of Certain Alpine Lakes.* — Brelim and Lederbauer 

 publish the first part of their paper on this subject, and analyse the 

 plankton of certain lakes in North Tyrol, ranging in height from 

 915 m. to about 2400 m. above sea level. They intend to examine also 

 certain lakes in South Tyrol, Carinthia and upper Austria. They propose 

 to deal with several questions of general interest in the matter of dis- 

 tribution, which they will discuss in the last part of the paper when the 

 flora of the individual lakes has been described. 



Morphology of Diatoms.f — C. Mereschkowsky embodies many of 

 the results of his large experience in the study of Diatoms in a book 

 with the above title. It is divided into two parts : (1) Historical, and 

 classification of Diatoms ; (2) the endoclirome of Diatoms. A complete 

 resume is given of the literature dealing with morphology of diatoms, 

 and this is followed by a treatment of classification on his own new 

 system. He divides Diatomacese into two classes : (1) the mobile, or 

 llaphidiophorese or sexual ; (2) the immobile, or Anaraphideae or 

 asexual. The former is characterised as follows : with raphe ; mobile ; 

 endochrome almost always plate-shaped ; the auxospores formed sexually. 

 The latter is defined thus : without raphe ; immobile ; endochrome 

 generally granular ; auxospores formed asexually. Each of these main 

 groups is divided into respectively, Raphidese, Carinataj, Archaidese 

 and Bacilloidea3, Centrales, with sub-divisions. A table of the system 

 shows the phylogenesis of Diatoms. The second part of the book 

 contains a detailed description of the endochrome (chromatophores) 

 and its contents. The author maintains that endochrome serves as a 

 systematic character, since in most cases it remains constant in form 

 and position. The elaioplasts are also constant in many species. 



Diatoms from Madagascar.^ — P- Petit enumerates the diatoms 

 collected at Fort Dauphin by Ferlus, and at Nosi-be by Corre, form- 

 ing together a fairly representative list of Madagascar species. A 

 novelty in distribution is Actinojrtychas splendens var. californica, pre- 

 viously recorded from San Francisco. Many descriptions of already 

 existing species have been corrected or completed, and ten species are 

 figured. 



* Ver. K. K. Zool.-bot. Gesell. Wien, liv. (1904) pp. 48-58 (3 figs.). 



t Kasan, 1903, 427 pp., Gcol. pis. 



% Assoc, franc,. Avancem. Sci., 1902, 10 pp., 1 pi. Paris. 1903. 



