ZOOLOGY AND BOTANY. MICROSCOPY. ETC. 199 



the limestone is being dissolved, apparently with some rapidity, in the 

 adjoining and, on the whole, similarly situated loughs of Corrib, Mask, 

 and Conn. 



Phytoplankton from Madrid.*— A. Forti records the first collection 

 of fresh-water phytoplankton from Spain, made by himself in the 

 " Estanque grande " in the park of Buen Retiro, Madrid. It is a 

 shallow rectangular lake, measuring 300 by 100 metres, and there is 

 an absence of Phanerogamic or Bryophytic vegetation round its shores. 

 It is therefore not surprising that the occurrence of Chlorophyceffi in 

 the lake is insignificant. On the other hand, the Cyanophycefe, and 

 more especially the Chroococcacege, are very richly developed — so much 

 so as to give the water the appearance of a Flos Aquae. They re- 

 present more than half the mass of the entire plankton. The most 

 common species is Glathrocystis aruginosa Henfr., while limnetic 

 Diatoms, Peridiniese, and Oscillatorife, are either sporadic or entirely 

 wanting. The fauna is copious. These results are gathered from two 

 surface samples taken by dragging an Amberg net behind a boat 

 going at moderate speed, and one vertical sample taken in the deepest 

 part of the lake (4-o m.) on August 23, 1901, in brilliant weather. A 

 list of 21 species, including a few zooplankton, is given, with notes 

 appended to each. 



Plankton of Lakes in Russian Lapland.f — -K. M. Levander gives 

 an account of the plankton of six lakes in the Kola peninsula, and his 

 work may be summarised as follows. The samples are very rich in 

 plankton species. It is characteristic that so many shore forms occur in 

 the plankton. There are many species of Desmids. Analuena Jlos 

 aqim and Goelosphcerimn Naegelianum are the most common Myxo- 

 phyceffi. Among the Protococcaceaj, Botryococcus Draunii is tlie most 

 predominant form. Among the Diatoms, TabeUaria fenestrata and 

 T. flocculosa occur in large quantities ; also Asterionella and Fragilaria 

 crotonensis are common, while the Melosirfe are rare. Myxophyceae, 

 9 Protococcacete, 2 Zygnemacese, 30 Desmidiaceae, 11 Diatomaceas, 

 8 Flagellate, and 3 Peridineae, have been found. The paper is. 

 illustrated. 



Scottish Fresh-water Plankton.|— W. and G. S. West continue their 

 studies on the fresh-water plankton of the Scottish lochs. Material was 

 collected from more than twenty of the lochs in Perth, Inverness, Ross^ 

 and the Outer Hebrides. A detailed account is given of the plankton 

 investigated, followed by a list of species in tabular form, including 

 algge from Loch Tay, Perthshire, and from Loch Lazadale, Harris,, 

 previously recorded by the authors. Collections are also included 

 from lochs in Sutherland and Inverness, made by J. ]\Iurray. The 

 PeridineiB were worked out by Lemmermann of Bremen, who describes 

 a new species of Feridininm. The authors describe three new species 

 and many new varieties, most of them having been found in Loch 

 Fadaghoda, Lewis. Certain rare Desmids are here recorded for the first 



* Atti Soc. Nat. Modena, viii. (1906) 9 pp. 



t Festschr. f. Palmen, ii. (Helsingfors, 1905) 49 pp., 3 pis. 



X Trans. Roy. Soc. Edinburgh, xli. (1906) pp. 477-518 (7 pis.). 



