320 DR. Е. E. FRITSCH ON FRESHWATER ALG.E 
red snow in this region does not attain to nearly so abundant а development 
as yellow snow *. The number of species present is also smaller. Оп the 
whole, sample 4 was richer in individuals than either 5 or 6 and showed а 
somewhat different constitution. Nearly all the forms present were in the 
resting-condition, so that some doubt attaches to certain determinations. The 
samples оЁ red snow included a good deal of non-algal matter, such as hairs, 
starch-grains, pollen-grains of Podocarpus, ete. 
In comparison with the flora of the yellow snow we have to note certain 
similarities and certain differences. Among the former we may reckon the 
occurrence of characteristic forms of the yellow snow flora, such as Scotiella 
antaretica and Raphidonema nivale. The former was found only in samples 
9 and 6, especially in the latter ; the number of individuals was small, but 
those present were of exceptionally large size (length of cell about 55 ш). 
They appeared to contain the same yellowish fat as in the yellow snow 
forms ; no resting-stages were observed. The Raphidonema was quite 
common (especially in sample 4), and in this case agreed absolutely with 
Lagerheim's description. Apart from fragments of an (4одошит, it was 
the only filamentous form present. 
There are two marked differences from the yellow snow flora. These are 
(a) the immense preponderance of red spherical cells, no doubt constituting 
the resting-cells of different members of Chlamydomonadacese (see below), 
and (0) the occurrence of various Diatoms in all three samples. The resting- 
cells are of. two chief types, viz. with and without a broad mucilage-sheath. 
The latter type are circular with а smooth, somewhat thiekened membrane and 
granular contents with a central pyrenoid (text-fig., A, р. 323) ; the diameter 
of these cells varies between 10 and 20 и. The red colouring-matter in the 
contents had been for the greater part taken up into the preserving fluid and 
the cell-contents appeared colourless or slightly greenish ; it is therefore 
impossible to say what the exact colour of these cells was in nature. А 
considerable quantity of fat was often present in these resting-cells. They 
reeall markedly the resting-cells (aplanospores) of Chlamydomonas nivalis 
(Spherella nivalis, Sommerf.), as figured by Wittrock T. Аз very few 
other stages of this Alga were found, the determination must remain 
somewhat doubtful. In one or two cases subdivision of the contents into a 
number of parts was observed, but this, of course, scarcely aids in determining 
the species. 
The second type of resting-cell (observed only in sample 4) closely 
resembles the other type except that the cells are surrounded by a broad 
sheath of mucilage about two to three times the width of the cell in diameter 
* Cf. also the remarks on the distribution of red and yellow snow, cited on pp. 297 from 
Mr. (now Dr.) В. N. Rudmose Brown's letters. 
T Wittrock, in Nordenskiöld, * Studier och forskningar, tab. З. fig. 1. 
о 
