F. Børgesen: Rhodophyceæ of the Danish W. Indies. 



11 



cells and between these there are thinner parts still consisting of 

 a single row of cells (Fig. 5 a). 



Figs. 5 d, e, /, g show transverse sections of filaments in differ- 

 ent stages of development; fig. 5 c? is of a filament still consisting 

 of a single row of cells, in fig. 5 e we find two cells and in fig. 5 / 

 and g several. As the figures show the cells lie scattered without 

 order in the whole filament. In this my plant differs essentially 

 from the description of Schmitz (1. c.) where the thallus is said 

 to be : "der ganzen Länge nach röhrig hohl, mit gallertgefülltem 

 Hohlräume". 



Now and then especially from the thicker parts of the fila- 

 ments branches grow out; these are commonly short, proliferation- 

 hke, consisting of a single row 

 of cells (Fig. 5 b, Fig. 6) ; only 

 rarely I have found them longer 

 and more like the main filaments. 



Each cell contains a starlike 

 red-violet chromatophore in the 

 middle of which a large pyrenoid 

 is present (Fig. 6). 



In some filaments , all or 

 nearly all cells were emptied, 

 the few remaining cells were nearly 

 spherical and with a granulated 

 contents. I take these cells for 

 the gonidia. I have not succeeded Fig. 6. Bangiopsis subsimplex (Mont.) 



in findincT othor kind of organs Schmitz. Part of a thallus showing 

 m imdmg otner Kma oi organs ^^^^^ ^.^^^ chromatophores and pyre- 



of propagation. noids. (About 250 : 1). 



While my plant seems to 



agree quite well with the description of Montagne it differs as 



pointed out above from that of Schmitz's by its solid thallus. 



Montagne referred the plant to the genus Compsopogon, while 



Schmitz created for it the genus Bangiopsis. It comes surely 



near to Bangia but differs essentially from this genus by the 



want of rhizines at the base and by the common presence of 



prohferations and especially by the rather irregular cell-division, 



the cells in Bangia being divided by radial walls and these as a 



result are generally wedge-shaped. 



The plant has been found only once growing upon a buoy in the 

 harbour of Christianssted, St. Croix. 

 Geogr. Distrib. Guiana. 



mm ' 



