observed, the two upper spores first escaped almost simultaneously and shortly 
after a third. During the liberation, the spores changed form when squeezing through 
the narrow split and afterwards regained the globular form. A liberated spore was 
seen to move between some filaments of the same species, likewise changing form 
when squeezing through the narrow interstice between the filaments. 
Germination of tetraspores and carpospores is easily realized in cultures, as 
shown by THURET (1878 p. 71, pl. 35 fig. 15), who obtained, however, only very 
young stages consisting of few cells. The seedlings in my cultures reached a greater 
size and began to branch (fig. 248). As mentioned by THURET, 
the seedlings resulting from the two kinds of spores are alike. N 
The germinating spore gives off two opposite germinating pn CES Il 
tubes, the one becoming the primary axis of the plant, the (Wr 0 
other growing out to a long articulate rhizine. The original NU || 
spore-cell remains for a long time distinguishable by its greater \\ M ul 
thickness, at least in the cultures. The branching of the pri- \ y |) 
IL\ | 
mary axis may begin immediately over it or at a higher level. 
Antheridia have been met with in April to September, 
eystocarps in June to October, tetrasporangia in June to Decem- 
ber and in January, but not in the spring. The cystocarp-bearing 
specimens are often smaller than the tetraspore-bearing ones. 
Sterile specimens are not rarely found in considerable number 
between the fertile ones, and they are then often larger than 
these. In the Smaaland Sea, in the Sound south of Hveen A 
and in the Baltic Sea, thus in the innermost localities, only 
sterile specimens were found. 
The species has been met with .at all seasons; that it PA 
has not been observed in the months of February and March is Fig. 248. 
certainly due to the fact that only very few collections have  Callithamnion corymbosum. 
: 3 6 Sporelings from Frederiks- 
been made in these months. It can without doubt continue  jayn. 4. 3 weeks, B, C. 4 
alive from one season to the next, but it can also accom- weeks old. 150 :1. 
plish its life-cycle during a short time, being thus ephemerous, 
and perhaps produce more than one generation in the season. The duration of life 
must at all events be short when it is epiphytical on Algæ or parts of Algæ which 
die in the autumn. It may be met with in well developed specimens at all seasons; 
it occurs, however, in the greatest quantity in summer and autumn, when it also attains 
its greatest development. Most of the specimens certainly die in the autumn. The spe- 
cimens found in winter are not in growth and without hairs (fig. 244) but may still 
bear tetrasporangia. Callithamnion hiemale Kjellm., Kylin seems at least in part 
to be such a winter-form of C. corymbosum, for a specimen of the named spe- 
cies kindly sent me by dr. KyLiN agreed with my winter specimens of the lat- 
ter by its structure and its corymbous ramification; the number of the nuclei 
could not, however, be ascertained in the dried state. A few hairs were still pre- 
So 
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Be in 
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