ZOOLOGY AND BOTANY, MICKOSCOPY, ETC. 195 



New Genus of Chlorophyceag.* — A. Borzi describes a new genus of 

 Chroolepidaceas, Zoddcm, allied to Pilinia Kutz., Microthamnion Kutz., 

 and Leptosira Borzi. It contains a single species, Z. viridis, which 

 srrows on the damp volcanic rocks of the island of Linosa in the 

 Mediterranean. It spreads itself as a green membranaceous crust over 

 the substratum, is 200-300 /x high, and consists of a mass of eonfervoid 

 filaments, which are much branched, and generally from one side 

 only. The interior of the mass gradually comes to have an almost 

 parenchymatous appearance, but at the surface the filaments are quite 

 distinct. A characteristic of this new genus is the presence of a single 

 parietal chromatophore inside each cell, shaped like a disk, and destitute 

 of pyrenoids and starch. 



British Desmidiaceae.f — W. & Gr. S. West have brought out the 

 •second volume of their monograph of the British Desmidiaceae. It con- 

 tinues the treatment of the Cosmarieaa, and deals fully with the genera 

 Euastrum, 31 icr aster ias, and Cosmarium. Two new species, Euastrum 

 cornubiense and Cosmarium subquadrans, and five new varieties of 

 existing species are described. There are 32 plates, containing both 

 coloured and uncoloured figures. 



Desmids of New Hampshire-! — J. A. Cushman concludes his list 

 of Desmids from New Hampshire, in which he records 253 species and 

 varieties. Up to the present time only 74 species had been recorded 

 from that State, so that 179 additions have been made by the author. 

 He notes that a granitic country, or one with old geological rocks, 

 furnishes a greater number of species than a soil of younger geological 

 origin. Thus from a single collection made at Pudding Pond, North 

 Conway, there were identified 126 species and varieties, exactly one half 

 of the whole number recorded from all sources in the State. The author 

 anticipates that many more species will yet be recorded from New 

 Hampshire. 



Plankton of Danish and Scottish Lakes.§ — C. Wesenberg-Lund, 

 who has published the results of his various studies on the plankton of 

 Danish Lakes, now makes a comparison between that and the plankton 

 of the lochs of the Caledonian Canal and a few Lowland lakes, especially 

 Loch Leven. His remarks are placed under the following headings : 

 General remarks on the natural conditions of the Danish and Scottish 

 lakes ; the organisms, and their relations to the different life-conditions ; 

 the influence of the organic life upon the lakes themselves and their 

 surroundings. A few words on his visit to the Lowland lakes are 

 followed by some general conclusions not connected with algae, and a 

 bibliography. In comparing the organisms of Denmark and Scotland, 

 he notes the great difference in almost every particular. The Scotch 

 lochs are marked by an excess of humic acid and a total absence of lime. 

 The Cyanophyceae are not abundant, nor are certain of the Diatoms ; 

 while the Desmids are astonishingly rich and varied. This rich Desmid 



* Nuov. Notar., xvii. (1906) pp. 14-16. 



t Printed for the Ray Society, London, 1905, x. and 204 pp., 32 pis. 



X Rhodora, vii. (1905) pp. 251-66. 



§ Proc. Roy Soc. Edinburgh, xxv. (1905) pp. 401-48 (2 pis.). 



O 2 



