20 
will be seen that the middlemost (primary) wall is inclined to the left, the two 
others to the right; the walls, however, do not intersect, in accordance with the un- 
usually narrow shape of the sporangium. 
After the evacuation of the tetraspores, the sporangial walls are kept for a long 
time; they swell and fill the conceptacle. They have been considered as paraphyses 
by Kürzınag and others, but such organs do not occur in the adult conceptacles 
(comp. ScHMITz and HAUPTFLEISCH |. c.). Small Sarcina-like bacteria sometimes 
form strings between the empty sporangial walls. 
Conceptacles are met with at all seasons, and ripe sporangia have been found 
in all the months of the year, most frequently, however, in summer. As a rule 
empty, ripe and unripe sporangia are found simultaneously, from which it must be 
concluded that the formation of sporangia continues during the whole year, in the 
winter only with diminished activity. At what moment the development of the 
conceptacles begins I cannot say with certainty as I have seen but a small number 
of young stages. The youngest of the observed stages (fig. 123 A, B) were met with 
in June, which might suggest that the development of the conceptacles begins in 
spring, when the growth of the crust must be supposed to be active. 
In older crusts the periodicity of the growth is marked by distinct limiting 
lines between the layers of the successive years. The upper line in fig. 121 probably 
represents the surface of the frond at the end of the foregoing season, but the lower, 
more irregular line does not represent an old surface; the deepenings are the bot- 
toms of emptied conceptacles, and the higher parts between them represent the 
limit of the crust after disorganisation of its upper parts. It really frequently hap- 
pens that the outer cell-layers die in winter over a greater or lesser part of the 
crust, and the faculty of growth is then often restricted to limited portions of the 
frond, which then become higher, and provided with conceptacles, while the other 
parts are low and sterile. 
The species is widely spread in the Danish waters, particularly in shallow 
water, also over the low-water mark, and in sheltered places, where it is often a 
characteristic element of the vegetation, covering the stones with a red crust in 
company with Ralfsia etc., frequently under Fucus. But it is also common in deeper 
water, even in the greatest depths where vegetation has been met with, e. g. in 
the North Sea at 31 meters depth, in the Little Belt at 26,4-m and near Bornholm at 
38 m, but it seems to be less abundant at greater depths. It has repeatedly been 
met with in a fructiferous state at about 19 meters depth, at Bornholm even at 
29 m. In very insolated localities in shallow water it takes a yellowish colour during 
summer. 
Localities. Ns: aF, off Thyboron, 31 meters, small sterile specimens; groin at Thyboren. — 
Sk: YU, Roshage, Hanstholm, 2 m, small sterile spec.; washed ashore near Bulbjerg, sterile; Hirshals, 
on stones adhering to the hapters of Laminariæ washed ashore after storm, sterile. — Lf: Ronnen near 
Lemvig, 3m, MA, off Jestrup, 5 m; Oddesund, stone slope, fr.; Nykebing and otherwhere in Sallingsund; 
aT’, Draaby Vig; Livø Bredning (C. H. Ostenfeld); west side of Feggeklit. — Kn: Herthas Flak, 21—25 m, 
ster.; Hirsholmene; Deget; Busserev; Frederikshavn; Nordre Renner. — Kim; Mariager Fjord, at Hobro; 
