380 
is found growing on Laomedea and on various alge, partly 
creeping with rhizoids, reaching a length of 1—3 cm. It has 
only been found sterile. 
Localities. Lf: near Jegindø Tap, 5,5 m; IT, West of Ejerslev 
Ron, 7 m. 
5. Ceramium Deslongchampsii Chauvin. 
J. Agardh, 1851 p. 122; Henn. Petersen”1908 p. 83 (89). 
This species which is principally characterized by the 
cortical bands being of almost equal height and breadth, 
and by the straight ends of the 
branches, has only been recorded 
with certainty from one locality, 
viz. the harbour of Frederikshavn, 
where it occurs constantly at 
the ends of the northern outer 
mole and of the northern trans- 
verse mole. It grows at low-water 
Fig. 320. 
Ceramium Deslongchampsi. mark and reaches a length of 
Part of frond with two bands. 4 cm. All the specimens collected 
Henn. Petersen det. 270: I. : 3 . 
were sterile till July 1923 when Fig. 321. 
specimens up to 6 cm high were met with, partly with Ceramium Deslongchampsi. Heap 
= É = of paraspores. 200 :1. 
tetrasporangia or paraspores. The sporangia were vert- 
icillate, the fertile joints much swollen. The heaps of para- 
spores are solitary or several on the same joint (fig. 321, comp. __ 
Harvey Phye. Brit. pl. 219). | 
Localities. Lf: Nykebing Mors (Bergesen), referred with doubt to this i 
species. — Kn: Harbour of Frederikshavn (April—August). 
6. Ceramium vertebrale Henn. Petersen. 
Henning Petersen, 1908 p. 63, 90 Fig. V. Tab. II Fig. 2. 
As shown by Dr. PETERSEN, this species is on the one hand 
related to C. diaphanum and C. strictum, on the other hand to 
C. Deslongchampsü. It is distinguished in particular by the last 
branches becoming straight, by the great number of articles in 
the internodes and by the thick cell-membranes. It reaches a 
length of 4 to 6 cm. 
Dr. PETERSEN did not find hairs in this species. I observed 
these organs in specimens gathered in August: the rare oc- 
Fig. 322. currence of hairs probably depends on the fact that the species 
Ceramium vertebrale. Part has only been recorded in July and August. Tetrasporangia 
of frond with tetraspor- 2 2 ks 
angia. 230:1. were observed in specimens collected in August at Bornholm; 
