308 DR. Е. E. FRITSCH ON FRESHWATER ALGAE 
of the latter are described * as having one or more parietal chloroplasts with 
or without pyrenoids, so that the probable occurrence of a single chloroplast 
with а pyrenoid in the Scotiella does not speak against a relationship with 
Oocystis. The latter genus is included by Oltmanns f in his Scenedesmacez, 
while Wille * refers it to the Оосуѕіасег ў. 
Before concluding the discussion of Scotiella antarctica, reference must be 
made to the fact that the resting-cells (fig. 15) above referred to this species 
show considerable resemblance to 7'rochiscia insignis, Hansg. (= Acantho- 
coccus plicatus, Reinsch), and to T. obtusa, Hansg. (= Acanthoccocus obtusa 
Reinsch) $. In the former case the cells are much larger than the resting- 
stages ascribed to the Scotiella, but in the latter case the dimensions ap- 
proximately agree. It would, however, be inadvisable at the present moment 
to attempt any further comparison between these forms. 
(d) BcorigLLA РОТХРТЕВА, F. №. Fritsch. (Pl. 10. figs. 18-21.) 
The second species of Scotiella, S. polyptera |, was, as above stated, only 
rarely found in the yellow snow material, but rather more abundantly 
in samples 11 and 15, from which all the figures were drawn (Pl. 10. 
figs. 18-21). Тһе material of this species was, however, so scanty, and the 
state of preservation of the individuals so bad in most cases, that only a brief 
description can be given. The cells are oval and of considerably smaller 
dimensions than those of Scotiella antarctica; in place of the six wings of 
the latter the cells are provided with numerous longitudinal wings, which 
generally have a somewhat spiral trend (fig. 18, and especially figs. 19 & 21). 
The wings do not stand off from the body of the cell nearly so prominently 
as in S. antarctica (ef. especially fig. 20, which is an oblique end-view of the 
organism). Each of the wings is undulated (fig. 18), and this fact together 
with the large number of the wings makes the cells present a notched 
crenate outline from whatever point they are viewed (cf. figs. 20, 21). At 
the two ends of the cells the wings bend inwards and terminate in a shallow 
sinus (fig. 20 ; also 21 & 18). The wings are solid, as in the other species, 
and appear as flat crenations in optical section (fig. 20). Аз regards the 
contents of the cells of ©. polyptera, in the few cases in which they could be 
made out at all there appeared to be a single chloroplast with a prominent 
pyrenoid (fig. 21) ; fat was not observed in the cell-contents of this species. 
ж Cf. Wille, in Engl. & Prantl, Nat. Pflanzenfam. Teil I. Abt. 2, p. 58. 
T Oltmanns, * Morph. и. Diol. d. Algen,' vol. 1, 1904, pp. 183 её seq. 
[А full diagnosis of the new genus and species with measurements will be found 
on pp. 326, 327. . 
$ Cf. Migula, * Kryptogamenfl. v. Deutschland, Deutsch-Osterreich u. d. Schweiz,’ 
ii. 1, p. 684, and pl. 35 к. fig. 5, pl. 35 r. fig. 10. 
|| moAvds, many ; mrepóv, а wing. 
