594 
the Algæ or the parts of the fronds to which they are attached die after having 
fructified. 
Cystoclonium purpureum is common in all the Danish waters from the North 
Sea to the Western Baltic Sea, whereas it has not been recorded in the Baltic 
Sea proper. It grows in depths from a little under low-water mark to 20 metres’ 
depth, rarely deeper (21.5 m in the eastern Kattegat, 24.5 and 35 m in the Little 
Belt), on stones and on various Algæ (Furcellaria, Halidrys, Fucus serratus, Phyllo- 
phora Brodiei, Ahnfeltia and several others), further on oysters and other shells 
of bivalves. The largest specimens have been met with in the North Sea, Skagerak 
and the Northern Kattegat, where a length of 50 cm can be reached. In the inner 
waters the length does not usually exceed 20 cm, and the largest specimen col- 
lected in the Western Baltic was only 13 cm long. 
The species is only little variable and no varieties or named forms can be 
distinguished. We shall merely mention that in exposed localities in the North 
Sea and Skagerak large specimens may be met with which are remarkable in 
having a number of long principal branches beset with numerous short branches 
of the second order in their whole length. 
Localities. Ns: Not met with at Esbjerg-Fane and on the groins at the entrance to the Lim- 
fjord. Vorupør, 3 m (S. Lund); XR, off Orhage, 11—13 m; in the bay at Ørhage (Klitmøller), 2 m. — 
Sk: YT off Helshage, Hanstholm, 5.5—13 m, at Roshage, 2m, mole immediately beneath low-water 
mark; YM, YN*, Bragerne 2.5—10.5 m; SY off Løkken; ZK off Lønstrup; several places, XO, VJ ete. 
off Hirtshals, 5—15 m and abundantly on the mole. — Lf: Common from one to 7 metres’ depth and 
from XV and LZ in Nissum Bredning to Hals mole; e.g. Oddesund, Thisted Bredning, Sallingsund, 
Live Bredning and Legster Bredning. — Kn: Common everywhere on stony bottom from Skagen 
harbour, Herthas Flak, 20 m and Læsø Trindel, 16 m, southwards. — Ke: Several places in Fladen, 
Groves Flak, Lille Middelgrund from 10—22 m, further GJ, OO and Gilleleje harbour. — Km: Several 
places from Læsø Rende to NC off Fornes, 4—11 m. — Ks: Several places from Grenaa harbour to 
Hastens Grund and D, grønne Revle. — Sa: Numerous localities from 0 to 15 metres’ depth. — Lb: 
Several places, from 1 to 35 metres’ depth, from Bogense harbour to dH east of Hesteskoen, 15 m. — 
Sf: Several places. — Sb: Several places, 1 to 19 m. — Sm: S.E. of Masnedo, c. 3 m. — Su: Helle- 
bæk; Kronborg; PZ, east of Hveen, 13.5 m; Taarbæk Rev, 12 m; off Skovshoved, 11 m. — Bw: bY 
south of Als; cG off Kegnæs; cE, Middelgrund south of Als, 13 m; DX Vodrups Flak, 13 m; DV south 
of Marstal; LA, south of Lolland, 7.5 m; UL, Øjet 20 m; KY, Femerbelt 12 m. 
Some specimens of Cystoclonium purpureum gathered in the neighbourhood 
of Frederikshavn and in the Limfjord were set with numerous tumours reaching a 
diameter of 2.5 mm or more. The smaller tumours are globular with even surface, 
the larger more irregular, somewhat resembling cauliflower. They are seated on 
both the thin and the bigger branches; in the first case they often cause a back- 
ward bending of the frond (fig. 598). Small shoots of Cystoclonium may issue 
from the surface of the tumours (fig. 598 B). The colour is bright, nearly white, 
yellow or rose to red-brown. 
Such tumours have been shortly mentioned as early as 1808 by TURNER 
(Fuci, p.18, plate 9, figs. f,g,h) who described them as swellings ‘unconnected 
