250 
The conceptacles of sporangia are proportionally higher than in M. Lejolisü, 
hemispherical or subhemispherical, the height being frequently the half of the 
breadth. The cells surrounding the ostiole 
are usually little characteristic, forming no 
real peristome; they may be somewhat lengthe- 
ned towards the opening, but take, as it seems, 
scarcely the form of papillæ, and do not as a 
rule protrude outside the ostiolum. In some 
cases, however, they are elongated, going out 
in a prolongation of the surroundings of the 
ostiole in a short spout, resembling that of 
the antheridial conceptacles of M. Lejolisii and 
M. limitata, but thicker (fig. 169 A). This 
character, however, is not constant, being met 
with only in some of the conceptacles but 
wanting in others, usually most. When seen 
from above, the ostiolum appears sometimes 
surrounded by a rosette consisting, as it seems, 
of very low papillæ (fig. 168 D), in other cases 
no such structure is to be seen. 4-parted spor- 
Fig. 169. 
Melobesia Fosliei, from Tonneberg Banke. A, verti- . R à B > . 
cal section of sporangial conceptacle with orifice angıa were found in all the specimens examı- 
prolonged in a spout. B, vertical section of cysto- 
3 ned, but 2-parted ones of the same size were 
carpic conceptacle. A 350:1. B 560:1. 
found in the same specimens. As I have 
examined only dry specimens in which, as is well known, most of the sporangia 
have been emptied by the desiccation, it could not be stated whether the 2-parted 
sporangia were fully developed or not. I am inclined to suppose that 4-parted and 
2-parted sporangia normally occur simultaneously. 
The antheridial conceptacles were usually not well preserved in the dried 
material, but it could be seen that the spermatia were not produced at the end of 
long sterigmata as in M. Lejolisii. In one case the ostiole was found prolonged in 
a spout. 
The conceptacles of cystocarpia were smal- 
ler than those of sporangia, and a little lower in 
relation to their breadth; the ostiole was simi- 
lar in structure to these. 
The specimens growing on Polysiphonia ni- 
grescens agree in all essential points with the 
others; the cells of the monostromatic frond 
were only a little broader, 9—13 y. A number 
of the conceptacles were provided with a well 
Fig. 170. 
Melobesia Fosliei, from Bragerne. Vertical sec- 
developed spout, containing elongated cells, the om of frond with antheridial and cystocarpie 
0 4 : conceptacle. Below another section of the 
rest were without any projection. It appeared latter showing the orifice. 560:1. 
