104 L. KoLDERL'P Rosenvinge. 



to the genus Cruoriopsis, as a new species. At all events it cannot 

 belong to the genus Cruoriella, the sporangia not occurring in ne- 

 mathecia but scattered in the very crust. It reminds one somewhat 

 of Cruoriella armorica Hauck (1885, p. 31, non Crouan) which is 

 referred to the genus Cruoriopsis by Batters (1896, p. 387) under the 

 name of C. Hauckii. De-Toni (1905, p. 1690), has certainly protested 

 against its translation to this genus, as it has terminal sporangia; 

 this however does not appear convincing to me, the diagnosis of 

 the genus Cruoriopsis containing nothing very precise as to the posi- 

 tion of the sporangia (comp. De-Toni 1. c. and Schmitz und Haupt- 

 fleisch (1897, p. 535)). In Cruoriopsis cruciata Dufour the sporangia 

 are certainly lateral on the filaments (comp. Zanardini (1876), Tav. 

 86), but in our species lateral sporangia also occur though more 

 rarely than the terminal ones. I think it therefore most correct, at 

 least provisionally, to refer it to the same genus. 



I have been able to compare our plant with a microscopical 

 preparation of Cruoriopsis Hauckii Batt. from Plymouth, kindly sent 

 me by the late Mr. Batters, thus an original specimen. It differs by 

 having thinner erect filaments, ca. 4 /г thick or a little thicker, con- 

 sisting of more elongated and more thin-walled cells. The sporangia 

 are more lengthened, narrower, 21 — 25« long, 7 — 8fi broad, always 

 terminal on the ordinary erect filaments, scattered in the crust; the 

 divisions are cruciate but oblique. In the basal layer numerous 

 transversal fusions occur. 



Through the kindness of Mrs. Weber — van Bosse I have also 

 been able to examine two microscopical preparations of Cruoriella 

 armorica Hauck, from the collection of Hauck, originating from 

 Naples. This plant is also different from the Greenland one. The 

 basal layer consists of broad cells arranged in regular radiating fila- 

 ments, the erect filaments are thinner, sometimes dichotomous above. 

 The sporangia are always terminal, they are larger, 46 — 56 /y. long, 

 26 — 28 /J. broad, regularly cruciate. 



Loc. Along ttie Koldewey Island, Aug. 26th 1907 (No 556). 



Rhododermis Crouan. 

 8. R. elegans Crouan. 



K. Rosenvinge (1898 I) p. 18. 



Crusts of this species, recognizable by their dull rose-red or 

 light purple colour have been found growing on stones from various 

 localities. They are always polystromatical and may be up to 20 

 cells thick and even thicker. The vertical filaments are 7 — 9 ^ 

 thick; the height of the cells is variable, sometimes about the same 



