_615 
as in the vegetative cells, but the pyrenoids are easily observed. In the exhausted 
spores the chromatophore is very distinct (fig. 613 D); its arms are shorter than 
in the vegetative cells. In the living spores the chromatophore was red, while the 
pyrenoid appeared with a yellowish colour. In a certain position the chromatophore 
showed an incision on one side where the nucleus probably was situated. The 
living spores showed no amoeboid changes of shape, but were able to execute 
gliding movements on the slide.! 
The Danish plants are here referred to Erythrotrichia reflexa although they 
are almost all unbranched and their dimensions larger than those of the French 
specimens, and though there seem also to be differences as to the attachment organ. 
Crovan attributed to his species a “Racine discoide incolore”. I have not observed 
the attachment organ of the original specimens in Crouan’s Exsiccate No. 394, 
but I have seen the attachment organs in specimens of the same species from 
Biarritz communicated by Borner (herb. THURET), and these agreed with those of 
the Danish specimens; I think, therefore, that Crovan’s short description of the 
attachment disc is founded on some incomplete observation. Colourless attachment 
organs are otherwise not known in the genus Erythrotrichia. As to the nearly 
complete want of ramification in the Danish specimens, it is noteworthy that only 
one little branch has been met with, although the species has been observed 
repeatedly during recent years. On the other hand the greater part of the specimens 
examined from the collection of Crovan were unbranched, and 
all the filaments examined of the specimen from Biarritz were 
unbranched. The greater thickness of the filaments in the Danish 
specimens is perhaps due to the different external conditions. As 
long as Er. reflexa and its variation is not better examined in differ- 
ent localities, it is impossible to decide with certainty whether the 
Danish species is the same as that from the coast of France. 
The species was found growing on various Algæ (Polysi- 
phonia urceolata, Cystoclonium purpureum, Sphacelaria saxatilis and 
Callithamnion Hookeri) at 1 to 19 metres’ depth; it was only 
observed in July and August. 
Localities. Kn: N.W. end of Tonneberg Banke; Hirsholm harbour (Henn. 
Petersen); Frederikshavn harbour; Borrebjergs Rev, Marens Rev. 
Fam. Naccariaceæ Kylin 1928. 
Atractophora sp. 
In July 1929 I found on a stone picked up from a depth 
of about 2 metres in the neighbourhood of Frederikshavn a small 
red Alga, only 2 mm high, issuing from a circular disc. As the 
Fig. 614. 
{iractophora Sp.? 33:1 
! Comp. L. KorneruP ROSENVINGE, On Mobility in the reproductive Cells of the Rhodophycee. 
Botan. Tids. 40 p. 72. 
