ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 639 



lakes, which he treats in detail. He has worked out the periodicity of 

 the diatoms and Myxophyceae, and gives the characteristic species for 

 the various months of the year as they occur in the Great Plon Lake. 

 He finds that the colder seasons of the year are better suited to the 

 prevalence of diatoms, and the warmer seasons for the Myxophyceae. 

 After a general comparison of the algal flora of the four lakes, the 

 author gives observations on a certain number of species of Lywjbya, 

 Anabcena, Gloiotrichia, &c. 



0. Zacharias * gives a list of the algae which he finds respectively in 

 six stagnant ponds in the neighbourhood of Plon. Many novelties are 

 described and interesting species are recorded, — such as Closterium lima 

 Perty, G. Ceratium Perty, Vaucheria rhomboides Breb., in large quantity, 

 Navicula subtilissima (determined by Reichelt), Atr actinium Schmidtei 

 Zach. nov. gen. et sp. near Scenedesmus, and Selenococcus farcinalia 

 Schmidle et Zach., &c. 



Tide-Pool Vegetation.! — S. A. Skinner has made a careful study of 

 eight pools at Port Renfrew and publishes the result of his investiga- 

 tions, made both at high and low tide. He gives "the Location," 

 " Exposure to Tide," " Shape and Dimensions," and " Flora : Kind and 

 Distribution " of each pool, and concludes his paper by a short sum- 

 mary of generalisations as to the effect on the algae of wave-action, 

 slope of the walls, and condition of the bottom. He also indicates 

 other factors which would affect algal growth and commends these 

 subjects of investigation to other botanists. 



Algae of the Gulf of Naples.! — Angelo Mazza records in a list, 

 which was begun last June, lh>9 species of marine algae from the Gulf 

 of Naples. He includes the records of Falkenberg and Berthold as 

 well as his own collections. Critical notes are appended to many of the 

 species-names. 



Algae from Central Asia and China. § — R. Gutwinski gives a list, 

 mainly consisting of diatoms, of 173 species collected in various 

 localities of Central Asia and China by Dr. J. Holderer. A list of 

 twenty-two algae collected by him has been already published in 

 Hedwigia, xxxix. pp. 141-3, and the diatoms and other algae here 

 enumerated belong to the same collection, and include specimens from 

 eighteen different localities. A plate shows several of the more inter- 

 esting species, including three new varieties. 



Fossil Algae of North America.— D. White (| describes and figures 

 two species of Gonostichus Lesquereux (? Acetabulariae), namely G. 

 Broadheadi Lesq. and G. prolifer Lesq. from the Lower Coal Measures 

 of Missouri. 



The same author^ describes a new genus of fossil algae, Thamno- 

 cladus, placing in it one species T: GlarJcei, from the palaeozoic strata of 

 East Windsor. It differs from Psilophyton and recalls in appearance 



* Ploner Berichte, 1903. See also Nuov. Notnr., xiv. (1903) pp. 124-6. 



+ Minnesota Bot. Studies, iii. (1903) pp. 145-55. 



X Nuov. Notar., xiii. (1902) pp. 125-52 ; xiv. (1903) pp. 1-17, 97-105. 



§ Ball. Intern. Acad. Sci. Cracovie. No. 4 (1903) pp. 201-26 (1 double plate). 



1| ' Fossil Flora of the Lower Coal Measures of Missouri,' Washington, 1902. 



If N. York State Paleontologist, 1901 ; Albany, 1902 (2 pis.). 



2 T 2 



