NO. 1 TAYLOR: PACIFIC MARINE ALGAE 75 



or 2-4 fairly close together, obliquely placed on very short stalks 14-17 ju, 

 diam., the stalk cell perhaps at first formed by two walls but at maturity 

 represented by a refractive disk 4-8 /x thick; sporangia cylindric-oval, 58- 

 90 /A diam., 121-180 /x long. 



This plant is of about the same size as D. marina (Lyngb.) Kjellm., 

 (Setchell & Gardner 1920, p. 165), but the sporangia are clearly cylin- 

 drical in midsection, with slightly decreased and rounded ends, and so 

 quite distinctive. 



Ecuador: Guayas, in mats in shallow water on the rocky south- 

 eastern side of Pta. Santa Elena, Salinas, no. 34-464 (TYPE), 8 Feb. 

 1934. 



Derbesia prolifica n. sp.^'^ 

 Plate 2, Figs. 1-6 



Plants matted below, tufted above, to 1.5 cm tall, the erect filaments 

 frequently and chiefly laterally branched, flexuous or a little arcuate, 

 reaching 120-250 ju, diam., the zoosporangia very numerous, seriate and 

 often unilateral on the erect branches, borne at right angles or a little 

 ascending, stalked, the stalks 32-42 fi diam., generally short but some- 

 times one or two diameters long, the sporangia subspherical, to 160-210 fi 

 diam. 



Ecuador: Archipielago de Colon, in intertidal pools on an islet in 

 Gardner Bay, I. Espanola, no. 34-425 (TYPE), 31 Jan. 1934. 



Derbesia Hollenbergii n. sp.^^ 

 Plate 1. Figs. 7-9 



Plants tufted, epiphytic, 1.0-1.5 cm tall, the filaments from 60-142 fi. 

 diam., generally 100-120 /t, the erect axes occasionally branched, cross- 

 walls infrequent, near the top flexuous or arcuate ; zoosporangia solitary 

 or 2-3 on an axis, or perhaps formed, discharged, and dropped in rapid 



5'?^ Derbesia prolifica n. sp. — Planta infra implecta, supra caespitosa, ad 1.5 cm 

 altitudine, filamentis erectis saepe lateraliter ramosis, 120-250 jx diam.; zoospo- 

 rangiis plurimis, seriatis et saepe unilateralibus, patentibus aut ascentibus, in 

 stipitibus brevibus positis, 32-42 |idiam. ; sporangiis subsphaericis, 160-210 \i diam. 

 Planta typica in loco dicto Gardner Bay, I. Espafiola, Ecuador, legit W. R. Taylor 

 no. 34-425, 31 Jan. 1934. 



58 Derbesia Hollenbergii n. sp. — Planta epiphytica, caespitosa, 1.0-1.5 cm alti- 

 tudine, filamentis 60-142 ^ diam., axibus erectis interdum ramosis, supra flexuosis; 

 zoosporangiis singulis aut 2-3 simul, stipitibus circa 25 [.i diam., 1-2 plo longiori- 

 bus quam latis; sporangiis late turbinatis, 185-210 n diam., 150-165 \i long. Planta 

 typica in loco dicto Black Beach Anchorage, I. Santa Maria, Ecuador, legit W. R. 

 Taylor no. 34-264, 18 Jan. 1934. 



