327 



original specimens in HARVEY'S Herbarium, must be considered as 

 the var. typica. The other more slender and softer plant I propose 

 to call var. laxa. 



FALKENBERG suggests, not having made any observations regard- 

 ing the localities in which the two forms grow, that the var. typica 

 ought to originate from shallow water while the var. laxa on the 

 other hand ought to be a deep sea form. My 

 observations have not quite verified this 

 supposition. To be sure the var. typicais often 

 found in shallow water in exposed places 

 with strong light, but I have also dredged 

 this form once in a depth of ten meters and 

 another time in about twenty meters. As 

 to the var. laxa this was once found in shal- 

 low water in a lagoon growing in the shade 

 of the mangroves and therefore at a place where 

 it might be exspected to occur, but another 

 time it w r as gathered in shallow water behind 

 Long Reef at Christianssted, a rather exposed 

 place with strong light. 



The specimens with tetraspores were ga- 

 thered in the month of January. 



HeterosiphoniaWurdemanniis often found 



rig. 6'2b. Heterosipnonia 



upon other larger algse. Between its branches Wurdemanni (Bail.) 



Falkenbergia Hillebrandii is often entangled. Falkb var. Zoara n. yar. 



a, sticniaium with rip<- 

 Heterosiphoma is most probably a com- tetrasporang-ia ; in the 



mon species along the shores of the islands ; k. asal P art the ^ are em P~ 



tied, b, ends ot ramuli 



I have gathered it only at the shores of St. transformed into rhi- 

 P ro ix zoids. c, transverse sec- 



tion of the thallus. 

 St. Croix: Christianssted s Lagoon, Long (About 180:1). 



Reef, White Bay, Casavagarden. 



Geogr. Distrib.: West Indies, Key West, Cadiz, Mediterranean Sea. 



Dictyurus Bory. 



1. Dictyurus occiden tails J. Ag. 



AGARDH. J., Nya alger fran Mexico (Ofversigt af Kungl. Vet.-Akad. 

 l-Y.i-handl., 1847, p. 17); Spec. Alg., vol. 11,3, p. 1243. KUTZING, F., Spec. 

 Alg., p. 673; Tab. phycol., vol. XII, t. 64. 



Unfortunately all the material preserved in spirit of this 



