MARINE ALGAE FROM EASTER ISLAND 



2 57 



The plurilocular sporangia (Fig. 7 b) arc roundish-quadrangular or obovatc. 

 Commonly they are about 40 ft long and 35 ;j. broad as is also the case in the 

 West Indian form, the measure given by me (1. c.) drawn from a rather large 

 sporangium. 



So far one is able to judge from material kept so long in formaline, there 

 appears to be several shorter or longer ribbon like chromatophorcs, irregularly 

 bent and with branches of different length in the young parts of the filaments, 

 while in the older ones the chromatophores are more like small roundish or 

 somewhat irregularly shaped discs. 



From Mrs. Geit's description and figures 1 of Ectocarpus spong/osus Dickie 2 

 I feel convinced that this species is the same as E. breviarticulatus, originally 

 described by I. AGARDH in 1847 on specimens collected by LlEBMANN at St. 

 Augustin, Mexico. 



Area of distribution: Pacific coast of Mexico, West Indies, Indian Ocean, 

 Kaster Island. 



Fig. 7. Ectocarpus breviarticulatus J. Ag. 



a 'sterile filaments, c. 45 /i; b (c. 25o /0 an d 



c (c. 2OO /0 pluriocular sporangia. 



Fig. 8. Ectocarpus sp. a filament with pluril- 

 ocular sporangium, c. 4B /i; b the sporangium, 

 c. 200 /i. 



E. spec. — Fig. 8. 



The figure represents all the material found, and I would not have men- 

 tioned the plant if it had not shown so much likeness to another ^Ectocarpus 

 spec.» mentioned by Mme. WEBER in the »Phaeophyceae of the Siboga», p. 131. 



' Barton, Ethel S., List of Marine Algae collected at the Maldive and Laccadive Islands 

 by I. S. Gardiner (Journ. Linn. Soc.-Bot., vol. 35, p. 479). 



2 Dickie, G., On the Algae of Mauritius (Journ. Linn. Soc, Bot., vol. 14, 1875, p. 191). 

 1 7 — 2!9K The Nat. Hist, of Juan Fernandez and Easter I si. Vol. II. 



