Son 
occur 100. The trichogyne decays quickly while the rest of the carpogonium may be 
kept for a longer time (fig. 303). 
Antheridia, carpogonia and tetrasporangia as a rule occur on distinct individuals; 
in two cases, however, tetrasporangia were found on cystocarp-bearing plants. 
Paraspores in Anthithamnion Plumula have been found in the Mediterranean 
by Scumirz and SCHILLER (1913 p. 3, Plate V). Such organs have never been met 
with in the Danish specimens. 
The germination begins, as in Callithamnion, by the division of the spore-cell 
by a transversal wall into two cells, one of which gives rise to the first rhizoid, 
the other to the primary axis (comp. Kırrıan and Kyrın 1915). Young seedlings 
were met with on the surface of and in the neighbourhood of the cystocarps 
(fig. 303). 
The species has been met with in several localities in the Danish waters with 
salinity of 2 p.c. or higher, but it does not occur in the Limfjord or in other 
fjords. The best developed specimens were found at Skagen, south of Grenen, where 
it reached a length of over 8 cm, and where it was found as the predominating 
species in 13 to 15 meters depth in a locality with clayey sand with molluses. In the 
Kattegat it otherwise reaches a length of 6 cm, and at Hellebæk in the northern 
part of the Sound 3 cm; but in the Samso water and the Little Belt it was only 
1,5 cm high at most. 
The relation of this species to A. boreale will be dealt with under the last 
named species. Only specimens from one locality in the Little Belt (EE) could be 
said to approach A. boreale by having longer cells in the lower part of the main axis 
and by the pinnæ bearing, though rarely, pinnulæ on the under side. 
The species has been met with in depths of 9 to 32 meters, and furthermore 
slightly below the surface on vertical granitic walls in the harbour ot Frederikshayn. 
It grows principally on mollusc shells and therefore often occurs on soft bottom, 
further on the tubes of Tubularia and on various Algæ, e. g. Rhodomela, Furcellaria, 
Phyllophora. It has only been gathered in the months April to October. The tetra- 
sporangia have been met with in July to October, the sexual organs in July and 
August and ripe cystocarps in July to October; the latter, however, more rarely than 
the sporangia. 
Localities. Ns: aF, off Thyborøn, 31m. — Sk: eX, north of Bragerne, 16 m; SY, north of 
Løkken, 13 m; ZK, off Lønstrup, c. 8 m; YL, XO and other localities off Hirshals, 11—15 m (Borge- 
sen, !). — Kn: Skagen, south side of Grenen, e. 5—15 m; FG and XJ, Herthas Flak, c. 20 m; YS?, north 
of Hirsholmene, 15 m; YX, east of Nordostrev, Hirsholm, 23—28 m; on shells of Ostrea, Frederikshavn 
(Ørsted 1840); off Frederikshavn, east of Marens Rev, c. 20 m (!, Ostenfeld), 11 m (Kramp); harbour 
of Frederikshavn; TP, Tonneberg Banke, 16 m; near Læso Trindel, 11—26 m; 3 miles W. of Læso 
Trindel light-ship 15 m. — Ke: FC, east of Læsø, 17 m; fH and fl, 1 and 3 miles W. by N. of Fladen 
light-ship, 17 and 30 m; ZH, ZI, Groves Flak, 32 and 26 m, soft bottom; EQ, east of Anholt; 14'/: 
miles S.S.E. of Anholt Knob light-ship, 10 m (C. A. J.). — Sa: MS, west of Endelave, 15 m. — Lb: North 
side of Fænø; EE, west of Feng, 15 m; Feng Sund, 10—15 m, — Su: Hellebæk (Schmidt 1873), 
