221 
The species forms crusts on stones and gravel, in depths from 5 to 24,5 meters. 
In one case it was found growing on a dead specimen of Lithothamnion calcareum. 
It has been found with sporangial conceptacles and cystocarpie conceptacles in 
May and September. 
Localities. Sk: Off Hirshals, 13 met. (F. Borgesen). — Lf: ZY, Nissum Bredning, 5 met. (deter- 
mination uncertain). — Kn: Herthas Flak, 20—23 met.; FF and TR, Trindelen, 23,5 and 15 met. 
Ke: IP and IL, Fladen, 20,5—24,5 met.; IK, Lille Middelgrund, 17—19 met. — Sb: GP near the light- 
buoy at Halskov Rev (no. 3171, see above); Strandby reef, W. side of Langeland (?). — Sm: VC, Vene- 
grund, 4—5,5 met. 
4. Lithothamnion glaciale Kjellm. 
F. R. Kjellman, Norra Ish. algfl. p. 123 (93) tab. 2 and 3. Foslie, Norw. Forms p. 13; Remarks p. 26. 
Mme P. Lemoine, Struct. p. 92. 
Nearly all the rather numerous Danish specimens referred to this species have 
been determined by FosLıE, who received them from me at different times and ac- 
cordingly gave them different names. In 1895 he described and figured Norwegian 
specimens, corresponding exactly to those mentioned here as var. Granii, under the 
name of L. flabellatum f. Granii. Later on this variety was referred to L. glaciale, 
an opinion which has only been expressed in Rev. Surv. (1900, p. 11, where after the 
name L. Granü, which is here a nomen nudum, is added: “(L. glaciale f. ?)”). As late as 
in 1905 FosLie referred specimens of these algæ to L. glaciale, partly to f. Granii, 
partly to other forms. But in the same year (Remarks p. 59,') FosLıE established 
L. Granii as a distinct species. That he has been uncertain at the last as to the 
limitation of the species can be concluded from the fact that the same species, on 
p- 10 of the same paper, is mentioned as L. glaciale f. Granii. It is easy to under- 
stand that it has been difficult to come to a decision as to the delimitation of species 
when considering that FosLıEe (Remarks p. 28) “found it almost impossible to draw 
any line between L. Granii, admitted below, and L. glaciale”. L. c. p. 59 is said, as 
to the relation between L. Granü and L. tophiforme f. divergens, that there are many 
specimens “which are quite like each other in almost every respect, but that the 
specimens of one species show a somewhat greater tendency in one direction and 
the other in a different one”. It is however not to be seen in the named paper on 
which characters the difference between the two species really rests, save that L. 
Granii has thinner, usually more ramified branches. Some Danish specimens for- 
merly determined as L. glaciale, in part as f. colliculosa, are now (Remarks p. 34) 
referred to L. colliculosum which is here regarded as a separate species, while he 
had formerly considered it a form of L. glaciale; a description of it is given, but 
he does not emphasize how it differs from L. glaciale. As I cannot see any distinct 
difference between these specimens and some of those referred by FosLie to L. Granii 
I prefer to adhere to FosLie’s somewhat older opinion in regarding L. colliculosum 
and L. Granii as varieties of L. glaciale. 
1 FosLie’s “Remarks” appeard however only in 1906. 
