85 
after further transverse divisions it becomes a 3- lo 5-celled filament giving rise lo 
a number of branches. The trichogyne or a small remnant of it may often be 
seen some time afterwards on the convex side of the second cell in the main fila- 
ment of the gonimoblast (figs. 18 C; 20 E,H; 62 E, F, H). Unfortunately, I have not 
been able to follow the development of the cystocarp in Ch. hallandica, where it 
seems to be somewhat different (figs. 21,22). In four of the five sexual species men- 
tioned the carpospores arise only in the terminal cells of the branched gonimoblast. 
In Ch. gynandra, rhipidandra and Thuretii the branches are numerous, the cystocarp 
capituliform; in Ch. hallandica the number of the branches and the carpospores is 
very low. Ch. efflorescens is also in this respect different from the other species, 
the carpospores arising not only in the terminal cell but also in one or two of the 
cells lying behind in the filaments of the cystocarp, thus seriately (fig. 63). 
Sporangia occur in all known species of Chantransia. For some time it was 
generally accepted that monosporangia only occur in this genus, the older state- 
ments of tetrasporangia by Harvey being supposed to be due to some error. In 
later years, however, tetrasporangia have been pointed out with certainty in some 
species by Scumitz and HAUPTFLEISCH (1896), BORGESEN (1903) and Kyrın (1906 and 
1907), and I have been able not only to confirm these statements but also to find 
tetrasporangia in five other species, so that the occurrence of tetrasporangia is now 
established in eight of the species mentioned below (Ch. Thuretii, Daviesii, virgalula, 
polyblasta, cytophaga, Dumontiæ, efflorescens, pectinata). In Ch. Dumontiæ and poly- 
blasta tetrasporangia only have been met with, in the others also monosporangia. 
The division of the tetrasporangia is always cruciate, the first division being hori- 
zontal. Amoeboid movements of the monospores immediately after the liberation, 
similar to those described formerly for Helminthora divaricata, were observed in 
Ch. Thuretü (fig. 30). 
In most of the species provided with sex-organs sporangia occur in the sexual 
plants, in the monoecious species as well as in the dioecious Ch. rhipidandra. On 
the other hand, as the sex-organs are not present in all the plants, individuals 
bearing only sporangia will always be met with. In Ch.efflorescens only there is 
a sharp distinction between sexual plants and sporangia-bearing plants. This is 
perhaps connected with the fact that tetrasporangia occur in this species. As shown 
by Yamanoucxi! the tetrasporic plants of Polysiphonia violacea show double the 
number of chromosomes to that of the sexual plants, and a reduction in the number 
of chromosomes takes place by the formation of the tetraspores. If that is general 
for the Florideæ, a similar alternation of tetrasporic plants with sexual plants must 
be supposed to exist in Ch. efflorescens, and that is supported by the fact that the 
sporangia-bearing plants occur in the Danish waters chiefly in spring, the cystocarp- 
bearing plants in summer. In the sexual species with monosporangia such alter- 
nation of generations does not occur, and the reduction of chromosomes must be 
supposed to take place not in the sporangia but probably in the eystocarps, as in 
1 S. Yamanouchı, The life-history of Polysiphonia violacea. Botanical Gazette Vol. XLII. 1906. 
