1909-1910-] A. IgcB and their Study, 2 39 



Prof. G. S. West of Birmingham University, is appended. 

 The classification adopted is that of the same authority, as 

 given in his 'Treatise on the British Freshwater Algae.' 

 With the exception of a few slides showing the zoospores 

 of some Algge, all the specimens were mounted in a fluid 

 medium, and after many failures I adopted the one recom- 

 mended by Prof. West, namely, a 2 per cent solution of 

 potassium acetate with a trace of copper acetate. This 

 medium not only preserves the shape of the chromatophore 

 but also its natural colour, and it seems to answer well not 

 only for the Green Algae but also for the Myxophyceae, with 

 their great variety of tints. 



List of Fresh -water Alg^, exclusive of Desmids and 

 Diatoms, collected in Mid-Lothian in 1909. Cor- 

 rected AND verified BY PROFESSOR G. S. WeST, 



Birmingham. 



Class— RHODOPHYCE^. 



Order— NEMAIiIONACEiE. 

 Family — Helminthocladieae. 



1 . Batrachospermum vagum (Roth). Ag. (Pond in Royal Botanic Garden.) 



2. II monilifor'nie Roth. (Pentlands.) 



Family — Lemaneaceae. 



3. LerMLTiea torulosa Kiitz. (Pentlands.) 



Class— CHLOROPHYCEiE. 



Order— CH^TOPHORAIiES. 



Family — Ulotriehaceae. 



4. Ulothrix zonata (Web. et Mohr.) Kiitz. (Very common around Edin- 



burgh in running water.) 

 6. M suhtilis Kiitz., var. variabilis Kirchn. (Found between wet 

 stones in courtyard, Edinburgh.) 



6. Stichococcus hacillaris Nag. (On stone near Swanston.) 



Family — Chaetophoraeeaa. 



7. Ghcetophora elegans (Roth) Ag. (Elf Loch, Braid Hills.) 



8. II psi/ormzs (Roth) Ag. (Elf Loch, Braid Hills.) 



9. Myxonema tenue (Ag.) Rabenh. (Rainpool near Currie ; Elf Loch, 



Braid Hills.) 



10. Draparnaldia plumosa (Vauch.) Ag. (Elf Loch, Braid Hills.) 



Family — Trentepohliaceae. 



11. Trentepohlia aurea Mart. (On rocks on AUermuir Hill, Pentlands ; 



also on wall at Dalkeith.) 



