gular, but not lobed. A few gonimoblasts on the same specimens were, however, 
more irregular and lobed, much as in C. Furcellarie. A little special lobe is developed 
at the base of the gonimoblast, as in other species (fig. 258). In Phyc. Brit. pl. 230 
fig. 5 Harvey figures a cystocarp consisting of a small number of cells; perhaps 
it represents a young stage. I have not seen anything corresponding to the ‘cluster 
of favellæ’ figured in Harvey's fig. 4 The vegetative cells in the neighbourhood of 
the cystocarps usually produce rudimentary or more developed decurrent filaments 
which undoubtedly serve to strengthen the parts of the 
filaments bearing these heavy organs (fig. 258 B). 
On a tetraspore-bearing plant were found a number 
of sporelings apparently of the same species. Some of 
them were unbranched, others were branched, the rami- 
fication being irregular, alternate or secund. 
The species is nearly related to C. Furcellariæ from 
which it differs in particular by its robuster filaments, 
by the principal axes being corticated in their lower part, 
and by the ovate, not lobed gonimoblasts. 
The above description is founded on numerous living 
and preserved specimens from Frederikshayn. Elsewhere 
the species has only been met with in two other places 
in a sterile state. 
The basal part of the plants is usually enveloped 
by dense masses of detritus. In one case, the lowermost 
Fig. 259. part of the main axis had no cortex while the next 
Callithamnion roseum. Sporelings 5 2 
found on a tetraspore-bearing spe. following part had a well developed cortex. The species 
cimen of C. roseum. 24:1. has been observed with sexual organs and with ripe 
cystocarps and tetrasporangia in the months of July and 
August, the only months in which it has been collected at Frederikshavn. In this 
locality it has been met with only in the harbour from low-water mark to about 
one meters depth. In the Smaaland Sea it has been found in 11,5 meters’ depth. 
Localities. Li: Fuur “apportavit Kjolbye”, Herb. LyxGsye, determined by Lyngbye as C. ro- 
seum. A specimen from Limfjorden communicated by HoRNEMANN to Lyngbye in the same year (1826) pro- 
bably originates from the same locality. All the specimens are well developed but sterile. — Kn: Frederiks- 
havn, in the harbour for boats at the end of the north mole (1891—1923), on the head of the northern 
transverse mole and at the harbour of the pilots. Vesterø Havn, Læsø. — Sm: (2) Agersosund, 11,5 m, sterile. 
6. Callithamnion Furcellariæ J. Agardh. 
J. Agardh, 1851, p. 57; Kylin 1907, p. 167; Kolderup Rosenvinge 1920, p. 49; Kylin 1923, p. 56. 
Callithamnion byssoides Areschoug, 1850, p. 107, Tab. V, B; Svedelius, Ostersj. hafsalgfl., 1901, p. 126. 
Callithamnion hiemale Kjellm., Kylin, 1907, p. 170, teste Kylin, Botan. Notiser 1916, p- 65, ex parte. 
? As mentioned above, p. 330, a specimen of C. hiemale communicated to me by prof. Kyrın has 
turned out to be a C. corymbosum; but as the said author has found lobed gonimoblasts in other 
specimens, it seems that two species have been confounded under the name of C. hiemale Kjellm. 
