- 41 — 



and marsh-plants. Their shading influencé no doubt compen- 

 sâtes to a Large extenl for the absence of shrubs and trees around 

 the edge of the pond. 



The algal flora of the (tond is i*ich in species, and many of 

 thèse species are ai certain times of the year represented I > \ a 

 very large aumber of individuals. The followingisa listof the 

 dominant algal représentatives (i. e. those which at certain 

 times are a reallv conspicuous feature of the flora) : 

 Sphaerocystis Schrœteri, Chod. 

 Ineffigiata neglecta, W. and G. S. West 

 Microspora amoena (Kùtz.), Lagerh. var. gracilis, Wille. 

 Coleochaete scutata, Bréb. 

 Chaetophora pisiformis (Roth.), Agi 

 Zygnema insigne, Kûtz. 



Spirogyra cataeniformis (Hass.), Kûtz. (cf. p. 106). 

 quadrata (Hass.), Petit (cf. p. 106). 

 tenuissima (Hass.), Kiitz. 

 varians (Hass.), Kiitz. (only in 1907) 

 Mougeotia sp. (Diam. fil. 20-26[/.}. 



» parvula, Hass. 



Oedogonium Boscii (Le CL), Witlr. 

 » fragile, Wittr. 



Pringsheimii, Cram., forma (cf. p. 108). 

 multisporum, Wood (cf. p. 108). 

 Conferva bombycina (Ag.), Lagerh. and f. m'n>o>\ Wille. 

 Ophiocytium cochleare, A. Dr. 

 Anabaena catenula (Kiitz.), Bornet et Flahault. 

 Eunotia (Himantidium) Arcus, Ehrenb. 



» lunaris (Ehrb.), Grun. 

 Synedra radians, Kiitz. 

 Trachelomonas volvocina, Ehrb. 



» hispida, Stein. 



Euglena viridis, Ehrenb. 



The gênerai aspect of the algal flora is therefore determined 

 largely by fîlamentous Cônjugatae, diverse species of Oedogo- 

 nium, Microspora and Cou fer ni, with large quantities of 

 Eunotia Arcus, Ehrenb., in the winter-months. At one time 

 or another the three Flagellâtes, Ophiocytium cochleare, 

 Sphaerocystis Schrœteri and Ineffigiata play a more or less 

 important part, while Synedra radiansamd Eunotia lunaris 

 are important as epiphytes at certain times of the year. The 



