FRESHWATER ALG^E. 



C. subcaudata Wille) and Chloromonas alpina Wille, are, however, as yet only 

 known to occur in the Antarctic and in the north of Europe, although it is 

 hardly likely that future investigation will fail to reveal their occurrence in 

 intermediate regions. 



Another interesting case of distribution is that of species like Chloromonas 

 alpina Wille, and the genus Eucapsis, which have hitherto only been recorded 

 from alpine habitats. Parallel cases have long been known in the Arctic regions. 



The collections of the ' Discovery ' did not include any material of snow floras. 

 On the other hand, two samples (Cape Adare, January 9th, 1902 ; McMurdo Bay, 

 September 13th, 1902) came from the ice. It will be useful to give a list of the 

 commoner species found in these two habitats : 



CAPE ADABE (in freshwater ice under boulder). 



McMuBDO BAY (dull brick coloured ice). 



Chloromonas alpina Wille. 

 Eucapsis minuta sp. n. 

 Navicula muticopsis Van Heurck. 



cymatopleura W. and G. S. West. 



seminulum Grim. 

 Surirella angusta Kiitz. 



Microcyslis parasitica Kiitz. var. glacialis var. n. 

 parasitica Kiitz. 

 merismopedioides F. E. Fritsch. 

 Phormidium frigidum sp. n. 

 * Pleurococcus antarticus W. and G. S. West. 



dissectus Nitg. 



*Nostoc disciforme sp. n. 

 *Melosira sp. (cf. p. 46). 

 Fragilaria tenuicollis Heib. var. antartka W. and 



G. S. West. 

 Navicula seminulum Grun. 



muticopsis Van Heurck. 

 ,, cymatopleurus W. and G. S. West. 

 shacMetoni W. and G. S. West. 

 globiceps Greg. 



The colour of the ice in the second case was due to Microcystis parasitica 

 Kiitz. var. glacialis nov. var. The species marked with an asterisk did not grow 

 directly on the ice, but were epiphytes on the Phormidium. 



As above mentioned, the bulk of the material collected by the members of 

 the British National Antarctic Expedition consisted of Phormidium-sheets, with their 

 abundant epiphytic flora. The general character of this flora is sufficiently illustrated 

 by the Table on p. 4. Only a few samples comprised free-floating forms, the more 

 important of which were as follows : 



Chlamydomonas subcaudata Wille. 



intermedia Chod. 



ehrenbergi Gorosch. 



EtormicKum-st&ge and young packets of 

 Prasiola-cel\s. 



Penium sp. (cf. pp. 20, 21). 

 Microcystis marginata (Menegh.) Kiitz. 

 Merismopedia tenuissima Leinm. 

 Eucapsis minuta sp. n. 

 Phormidium antarcticum W. and G. S. West. 



Oscillatoria tenuis Ag. and otlier species. 

 Nostoc disciforme sp. n. 

 longstaffi sp. n. 

 fuscescens sp. n. 

 sphcerimm Vauch. 

 Nodularia quadrata sp. n. 

 Navicula muticopsis Van Heurck. 

 globkeps Greg. 

 shacMetoni W. and G. S. West. 

 cymatopleurus W. and G. S. West. 



