NO, 1 TAYLOR: PACIFIC MARINE ALGAE 163 



Leptocladia Binghamiae J. Agardh 



Setchelll912,p.250. 



Plants to 17 cm tall from a small cushion-shaped holdfast, in the 

 lower part cartilaginous, subcylindrical, branching nearly to the base, 

 irregularly alternate, with ill-defined main axes, the branches similar and 

 equaling it; above softer in texture, red, flattened, linear, one to occa- 

 sionally 3 mm broad, the margin irregular and subserrate, the teeth grad- 

 ing into branchlets of indeterminate growth; structurally showing a large 

 central axial cell row with considerable filamentous medulla about it, the 

 inner cortex of large colorless cells, the outer medulla of small cells in 

 rather irregular radial rows. 



Ecuador: Archipielago de Colon, dredged in 26-55 meters' depth at 

 Tagus Cove, I. Isabela, no. 34-136, 13 Jan. 1934. Ibid., dredged at 

 Academy Bay, I. Santa Cruz, no. 34-308, 20 Jan. 1934. 



Leptocladia laxa n. sp.^^ 

 Plate 38, Fig. 1 



Plants to 12-15 cm tall, gregarious from a small disciform holdfast, 

 almost wiry and blackish red, branching irregularly and alternate, or 2-5 

 branches arising together, more or less erect, the upper divisions sometimes 

 beset with a few erect spinelike branchlets ; terete or slightly compressed, 

 0.5-1.5 mm in diameter below, 0.3-0.5 mm in the upper divisions; struc- 

 turally showing a notable axial row of cells with thick walls which be- 

 comes 100-150 /A diam., and the cell cavity at first loosely but later 

 densely filled with irregularly longitudinal filaments attached here and 

 there to the cavity wall; the medulla around the axial row showing a 

 zone about 70 jn thick of relatively thin-walled longitudinal filaments of 

 irregular diameters, and outside this a regular pseudoparenchymatous 

 zone 2-3 times as wide of large thick-walled cells about 60 /x diam. in the 

 inner layers, less without; cortex ultimately about 70-125 /x thick, at first 

 of one cell layer, becoming finally a compact tissue of strict anticlinal rows 

 of cells 10-12 fi in lateral diameter, 12-15 /x deep (radially), appearing 

 rectangular in section, about 7-10 cells in each row. 



99 Leptocladia laxa n. sp.— Plantae ad 12-15 cm altitudine, gregariae, tenuibus 

 rigidisque, ramificatione irregulariter alterna, erecta, ramis superioribus ramulos 

 spiniformes interdum habentibus; ramis teretibus ad compressos, infra 0.5-1.5 

 mm lat., supra 0.3-0.5 mm lat.; cellulis ordinis axialis 100-150 M- diam. rhizoideis 

 demum impletis; medulla intus filamentosa, extra parenchymatica, cortice ex 

 ordinibus anticlinalibus 7-10 cellularum, 10-12 \i diam. constante. Planta typica 

 in loco dicto Point Hughes, Cabo San Lazaro, Baja California, Mexico, legit U. 

 R. Taylor, no. 34-603, 7 Mar. 1934. 



