102 
B; agama var. NOY. 
In the Danish waters plants only provided with sporangia are much more 
frequent than the above described sexual plants. As they greatly resemble these, 
I conclude that they belong to the same species; as they are different, however, 
not only by the want of sexual organs but also by somewhat larger sporangia 
they may be mentioned separately; and this will appear all the more legitimate 
when we remember the great likeness between the sporangia-bearing filaments of 
Ch. Thuretii and those of Ch. corymbifera Thur. (BorxET et THuRET 1876 pl. V), so 
that it is not excluded that the specimens mentioned here might represent a sep- 
arate species. 
As to the vegetative organs this form agrees with the sexual plants; the prin- 
cipal filaments, however, 
are as a rule a little 
thicker, namely 8—11 y 
in diameter. In some 
cases the thickness rea- 
ched 12 », and in some 
specimens from the North 
Sea (aF, fig. 32 F) it at 
tained even 132. On the 
other hand principal fila- 
ments only 7» thick may 
also occur. The cells are, 
as in the sexual plants, 
rather thick-walled; in 
Fig. 31. 
Chantransia Thuretii @, amphicarpa. From Busserev by Frederikshavn. A, the the lower part of the fila- 
branchlet bears a carpogonium. an antheridium and a sporangium. B, the 
branchlet bears a terminal carpogonium and a lateral emptied sporangium. C, ments they are proper 
lower part of a plant; above a branchlet with antheridia and a carpogonium. tionally short (seldom 
D, lower part of a ‘plant with two short descending filaments. A, B 50:1, B = 
C, D 350:1. ” however so short as in 
fig. 32 A), upward longer. 
The branches are somewhat thinner than the principal filaments and become 
thinner towards the apex. Sometimes they taper into very thin hair-like threads 
consisting of long, thin cells, the contents of which become colourless (fig. 32 B); 
this may also occur in a. Descending filaments at the base of the plants were not 
observed in typical specimens of this form. The chromatophores have the same 
shape as in the sexual plants. 
The sporangia have the same position and shape as in the sexual form but 
are somewhat larger. The length is usually 19—22 », but it may attain 24 „ and 
may sometimes be only 17,5 »; the breadth varies between 8 and 12 (7—13 yp). 
Only once have I seen a sporangium or a sporangium-bearing branchlet situated 
beneath another sporangium on thezsame cell (fig. 32 C, comp. fig. 30 A). In spec- 
imens collected towards the end of September in the Northern Kattegat (TP), 
