76 



ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 12 



succession, stalked, the stalks about 25 t^ diam., 1-2 times as long as 

 broad, the sporangia broadly turbinate, to 185-210 fi diam., 150-165 ft 



long- , ^ 



These plants in some details, but not in growth habit, suggest D. 



turbinata Howe & Hoyt (1916, p. 106, pi. 11, figs. 10-16). The spo- 

 rangia are relatively broader and the filaments coarser. 



Ecuador : Archipielago de Colon, abundant at Black Beach Anchor- 

 age, I. Santa Maria, no. 34-264 (TYPE), 18 Jan. 1934. 



Phyllosiphoniaceae 



Plants endophytic or endozooic, of large oval cells or branched fila- 

 ments without crosswalk, coenocytic, with many nuclei and many disklike 

 chromatophores lacking pyrenoids ; reproduction by aplanospores produced 

 in great numbers. 



OSTREOBIUM Bornet & Flahault, 1889 



Plants filamentous, of much-branched and apparently anastomosing 

 coenocytic filaments of veiy irregular form and variable diameter; aplano- 

 spores formed in the swollen ends of branches, and capable of germination 

 to new plants. 



Ostreobium Reineckii Bornet 



Filaments intricately spreading, the ends of the branchlets consistently 

 free. 



Bornet in Reinecke 1896, p. 269. 



Mexico: Is. Revilla Gigedo, as a boring alga in old corals, drifted 

 onto the beach, Sulphur Bay, I. Clarion, no. 34-63, 5 Jan. 1934. Ibid., 

 in old shell fragments dredged at sta. 917 from 50-75 meters' depth. Sul- 

 phur Bay, no. 39-28B, 16 Mar. 1939. Ibid., boring in the test of a key- 

 hole urchin, from 51-79 meters' depth, no. 39-24 p.p., 16 Mar. 1939 (all 

 det. by F. Thivy). 



Vaucheriaceae 

 VAUGHERIA De Candolle, 1805 



Plants forming considerable mats, particularly in shallow water, of 

 branched coenocytic filaments, the filaments without normal vegetative 

 crosswalls or constrictions; containing oil as the stored food reserve; 

 sexual organs sessile or stalked, single or grouped, segregated by cross- 



