F. Børgesen: List of species. 445 



freiliegende Lebensweise ein Aussehen und einen cylindrischen 

 Bau bekommen hat, ganz wie z. B. freihegende kleine Fucus- 

 Formen. Daraus erklärt sich auch ihre Sterilität«. Most probably 

 SvEDELius is right in this supposition. To be sure my plant was 

 not detached, but fixed to rocks. Nevertheless there is a possi- 

 bility that we may have to do with a form, the development of 

 which has been retarded because of unfortunate, external con- 

 ditions of life. It might perhaps belong to Padina, the basal part 

 of which in the young state is terete. 



Found in crevices in the small reef near the entrance to the Harbour 

 of St. Thomas. 



Geogr. Distrib.: Jamaica. 



41. Turbinaria trialata Kiitz. 



42. Sargassum vulgare C. Ag. 



— ■ var. ty pica. 



— var. foliosum (Lamx.) J. Ag. 



43. — lendigerum (L.) Kütz. 



44. — platycarpum Mont. 



45. — Hystrix J. Ag. ^) 



Rhodophyceæ. 



1. Asterocytis ramosa (Thwaites) Gobi. 



2. Goniotrichiim elegans (Chauv.) Le Jolis. 



3. — Humphrey! Collins. 



As already pointed out in a corrective note to the Part II, 

 1916, of the Rhodophyceæ, the plant which I, on p. 10, have referred 

 to Bangiopsis subsimplex is not this plant, but a form of Collins' 



1) Sargassum natans (L.) Meyen and Sargassum. fluitans Borgs, both 

 treated in length in my paper: "The Species of Sargassum found 

 along the coasts of the Danish West Indies with remarks upon the 

 floating forms of the Sargasso Sea" (Mindeskrift for Japetus Steen- 

 STRUP, København 1914, No. 32), and the last species described in 

 vol. I. of the present work p. 222, are both floating, pelagic forms, the 

 most common species of the Sargasso Sea. Now and then both forms 

 are washed ashore at the islands, but having never been found at- 

 tached there, they do not belong to the flora of the islands and are 

 therefore not mentioned in the list. 



