BOTANY 



Sclenastrum gracile, Reinsch. Puttenham Hapalosiphon intricatus, West. Puttenham 



Common Common 



Lagerheimia genevensis, Chodat. Mill Pond Lyngbya putealis, Mont. Richmond Park 



east of Chapel Wood srugineo-ccerulea, Gom. Esher to Kingston 



Tetrafidron horridum, West and G. S. West. versicolor, Gom. Dorking 



A species new to science; Puttenham Phormidium molle, Gom. Growing on 



Common Myriophyllum in Richmond Park 



Characium Pringsheimii, A. Br. Barnes and foveolarum, Gom. In a chalk pit at 



Mitcham Commons Dorking 



Ineffigiata neglecta, West and G. S. West. tenue, Gom. Wimbledon and Bisley Com- 



The genus itself is new to science ; the mans 



species occurs on Thursley, Esher West- Oscillatoria prolifica, Gom. Ranmore Common 



end and Puttenham Commons, also at in a pond 



Mill Pond east of Chapel Wood simplicissima, Gom. Wimbledon Common 



Stichococcus dissectus, Gay. Occurs on damp angustissima, West and G. S. West. 



walls about London Wimbledon Common 



Trochiscia aspera, Hansg. Wimbledon Common Polycystis flos-aquae, Wittr. Thursley Common 

 stagnalis, Hansg. Chobham Common 



No less than thirty species of Desmids have been found with 

 zygospores ; this proves that the conditions and places are often suitable 

 for their production. 



The total number of species which have been determined is nearly 

 500, in addition to which the writers have noticed several hundred species 

 of diatoms. Batrachospermum vagum (Florideae) is a large and graceful 

 alga which feels like frog-spawn, hence its generic name ; it can be 

 recognized without the aid of a microscope ; it occurs at Devil's Jumps, 

 Frensham, as well as in boggy pools at Thursley Common. Three 

 species of Coleochcete occur C. orbicularis at Crowhurst, C. soluta at Fren- 

 sham and Bisley, C. scutata being more widely distributed ; the species 

 of this genus are usually found attached to larger submerged aquatic 

 plants. Three species of Bulbochaete occur, B. mirabilis being of the most 

 interest, from Thursley Common. Monostroma bullosum is an uncommon 

 species ; it occurs on Mitcham Common. So many good species of 

 Desmids occur that it is a difficult matter to select certain of them for 

 special mention. Penium spirostriolatum, P. curtum and P. interruptum are 

 fine at Puttenham Common ; the last also occurs at Thursley Common, 

 and a large form in the Mill Pond east of Chapel Wood. The charac- 

 teristic and uncommon P. rufescens is found on Bisley Common. Other 

 rare species of Penia are polymorphism from Chobham Common, incon- 

 spicuum from Puttenham Common, cucurbitinum from Thursley Common, 

 and cruciferum from Wimbledon Common. Many species of Closterium 

 occur : Malirrvernianum at Esher West-end Common and Frensham, 

 pseudodiance at Thursley Common, Cynthia and regulare at Puttenham 

 Common, directum at Esher and Mill Pond east of Chapel Wood, Ralfsii 

 var. hybridum and setaceum at Puttenham and Thursley Commons, and 

 Ceratium on Esher and Wimbledon Commons. The genus Euastrum is 

 well represented and the following good species are worth enumerating : 

 affine and insigne at Chobham Common, pyramidatum, inerme, sinuosum, 

 ventricosum and cuneatum at Thursley Common, erosum var. notabile at 

 Bisley Common. The rarer species of the beautiful genus Micrasterias 



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