F. Borgesen: Phæophyceæ of the Danish W. Indies. 27 



Phycologicæ", vol. IX, pi. 5. Heydrich, 1. c. refers it to Hydro- 

 clathrus. 



Rosenvingea intricata is a much and very irregularly branched 

 species ; M lle Vickers figure is a good one. 



So far I have been able to see hairs occur in groups several 

 together both in the sterile part of the thallus and in the sori. 

 In M Ile Vickers' specimen the sori are roundish and sharply 

 defined. This agrees with Heydrich's statement that: "H. intri- 

 catus hat ziemlich scharf begrenzte Sori mit dicht gedrängt ste- 

 henden langen Gametangien, welche 12 — 15 meist doppelte Ga- 

 meten enthalten". The specimens of Liebmann I have examined 

 were sterile. So far as I have been able to see the cells contain 

 a single chromatophore. 



The third species, Rosenvingea jastigiata (Zanard.), is described 

 by Zanardini in „Phycearum Indicarum Pugillus", p. 134, tab. 3, 

 fig. 1 — 3 1 ) and where we have also a good figure of the plant; 

 of the f. major Reinb. (in Schmidt, Flora of Koh Chang, Part IV, 

 Bot. Tidsskrift, vol. 31, 1901) I have been able to examine origi- 

 nal specimens and finally Prof. Kuckuck has most kindly sent 

 me a preparation and a drawing of its sori. 



A well marked character is the group of hairs in the middle 

 of the roundish sori. A small disc-shaped chromatophore is pre- 

 sent in each of the epidermal cells. The habit of this plant is 

 very different from mine. 



As mentioned above Rosenvingea is nearly related to Chnoo- 

 spora in several ways. This genus has e. g. the same apex and 

 ramification but it differs essentially in its solid somewhat com- 

 pressed thallus - ). 



In Memorie del Reale Instituto Veneto, vol. 17, Venezia 1S72. 

 Mme Weber- van Bosse has had the great kindness to allow me to 

 examine a collection of Chnoospora implexa from the "Siboga"-Ex- 

 pedition. As this species seems to differ considerably from Chn. 

 fastigiata I give a short description. The solid thallus is somewhat 

 compressed and consists of larger cells in the middle, and small cells 

 with chromatophores at the periphery. Groups of plurilocular spor- 

 angia were found scattered over the surface of the thallus. In these 

 I found no hairs ; the latter occurred scattered in the sterile part of the 

 thallus, but not in great numbers. The plurilocular sporangia differ 

 somewhat from these I found in Rosenvingea ; they are more clavate 

 and in the uppermost end divided into several rows of small cells. 

 Above each sporangium we find the membrane of the mother cell. 

 In each cell was an irregularly lobed chromatophore, and sometimes 

 two occurred. From Chnoosp. fastigiata as we know this plant from 

 Mrs. Gepp's description 1. c. p. 507, this species differs in its marked 



