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



15 



ovalia — rectangularia, 33// long, 

 et 22// lat., interdum elongata 

 clavataque usque ad 64 // long., 

 27// lat. 



Growing upon an old Pa- 

 dina together with some other 

 Ectocarpi were found a few 

 specimens of a small Ectocarpus. 



The plant had creeping, 

 irregularly bent, basal filaments 

 from which the erect filaments 

 grow up (Fig. 9 /). The cells 

 in the basal, rhizoidal filaments 

 have rather thick walls and 

 are about three times as long 

 as broad, the diameter being 

 about 8 — 9 //. 



The erect filaments have 

 cylindrical cells, which in the 

 lower part of the filaments 

 are 2 — 3 times as long as their 

 own diameter, which is about 

 11//. Higher up the cells can 

 reach a length of up to 150 (j. 

 or nearly 14 times their own 

 breadth. The long cells in the 

 end of the filaments make these 

 hairlike, and are devoid or al- 

 most devoid of chromatophores 

 etc. (Fig. 8). The growth of the 

 filaments takes place by divi- 

 sion of the cells in the middle 

 and lower part of the filament. 

 A marked growing zone is 

 found at times, but not always. 



The chromatophore is 

 ribbonlike and irregularly rami- 

 fied (Fig. 9 b). 



From the cells in the 

 middle and lower part of the 

 filaments thin rhizoids are 

 occasionally found growing 

 downwards (Fig. 9 a). 



Fig. 8. Ectocarpus rhodochortonoid.es nov, 

 spec. Part of a plant. (About 40 : 1). 



