376 Fritsch and Takcda. — On a Species of Chlamydomonas. 
(Fig. 7 ; cf. also loc. cit., Fig. i, c). The chloroplast is a massive structure 
of a dark green colour which, as already mentioned, occupies the greater 
part of the cell. Four or more pyrenoids, more or less globular in shape 
and quite irregularly arranged, lie in a parietal position. The pyrenocrystal 
and amylaceous envelope can easily be differentiated by means of the usual 
stains. The small nucleus is situated in the centre of the cell. 
To the earlier description of the formation of daughter-cells (p. 344) 
we are able to add but little. Prior to division, the pyrenoids seem to 
increase in number (cf. Fig. 13). At the same time the gelatinous part of 
the cell-wall appears to acquire a very thin consistency. The first division 
is longitudinal, and takes place in a plane which is at right angles to that 
containing the two papillae, the constriction of the protoplast starting at 
the anterior end (Fig. 13). The second division, when it takes place, 
appears likewise to be longitudinal, but runs at right angles to the first 
division-plane. By the time that the daughter-cells have acquired their 
mature characteristics, their arrangement becomes irregular (Fig. 14), which 
appears to be due to active movements on the part of the new individuals 
(cf. also Fritsch, loc. cit., p. 344). We did not observe any further instance 
of division into eight (cf. Fritsch, loc. cit., p. 344). Prior to liberation of 
the new individuals the mother-cell-wall swells up very considerably and 
acquires a very thin consistency. 
As regards the affinity of C. sphagnicola , it may be compared with 
C. longistigma , Dill, C. gloeocystiform is , Dill, C. angulosa , Dill, and 
C. gigantea , Dill. 1 The first of these species (Dill, loc. cit., pp. 328, 354, 
Tab. V, Figs. 1-8) has a broad and flat papilla, somewhat recalling that found 
in the specimens of C. sphagnicola , in which but a single papilla is present 
(cf. above). It differs from our species in having a thin membrane, without 
any gelatinous layer, a smooth surface to the protoplast, and a long rod- 
like stigma. 
C. gloeocystiformis , Dill (loc. cit., pp. 340, 354, Tab. V, Figs. 37, 38), 
has a thick gelatinous membrane, in which an outer firmer portion and an 
inner gelatinous part could perhaps be distinguished, although Dill does 
not discriminate between the two, either in his description or in his figures. 
The species differs from C. sphagnicola in having but a single papilla and 
a solitary pyrenoid which is not parietal. 
C. angulosa , Dill (loc. cit., pp. 337, 354, Tab. V, Figs. 21-25), has a 
distinct papilla which is broadly conical in shape. The cell-wall is usually 
thin, and the gelatinous layer is only seldom developed to a slight extent 
at the posterior end. Moreover, this species possesses one, or rarely two, 
pyrenoids, which are axial, and a smooth protoplast. 
C. gigantea , Dill (loc. cit., pp. 338, 353, Tab. V, Figs. 25A-30), resembles 
C. sphagnicola in having a considerable number of pyrenoids, which here, 
1 Cf. Dill : Die Gatt. Chlamydomonas , &c. Pringsh. Jahrb., vol. xxviii, 1895. 
