MARINE ALGAE FROM EASTER ISLAND 



2 75 



The plant is richly incrusted with lime; in the dried specimens the branch 

 ends collapse. 



The colour of the dried plant is a dark red-brown. 



The short assimilating filaments usually consist of 3 cells, but 4 cells are 

 not uncommon: compare Fig. 20 b, a character to which KjELLMAN attaches 

 much importance. The basal cells in the filaments are spherical, about 50 u, 

 across, or a little longer than broad; the following cells gradually decrease to 

 about 20 u. 



In the long assimilating filaments the basal cells have nearly the same 

 size as those in the short filaments; in the cylindrical part the cells are about 

 16 ;j. thick and 1 l /a — 2 times as long, and slightly constricted at the cross walls. 



Fig. 20. Galaxaura collabens J. Ag. a part of specimen, c. 2 /i: b assimilating filaments with 



tetrasporangia, c. 13B /i- 



The plant is tetrasporic. The tetrasporangia (Fig. 20 b) are mostly terminal 

 on the long assimilating filaments; but now and then lateral occur, developed 

 from the subterminal cells. The tetrasporangium is nearly spherical in shape, 

 its diameter being 32 a. 



Most likely this plant 2s the tetrasporic form of the following- one. 



Area of distribution: West Australia, Easter Island. 



Sectio II. Microthoe Dene, J. Ag. 



G. spec. — Fig. 21, 22. 



A rather large form, about 10 cm high, forming a rounded, but rather 

 open bush. 



From the broad basal disc a great number of branches arise. They are 

 irregularly subdichotomously divided with joints of very variable length. The 



