180 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 12 



f. galapagense Foslie 



Foslie 1929, p. 30, pi. 48, fig. 14 (as Goniolithon frutescens f. gala- 

 pagense). 



The medullary cells ranged to 40 /x long in no. 34-340 and to 50 /j. or 

 a little more in no. 34-326. 



Ecuador: Archipielago de Colon, shores of Ba. Cartago, I. Isabela, 

 no. 34-352D, 13 Jan. 1934. Ibid.j littoral, in intertidal pools, I. Baltra, 

 no. 34-326, 22 Jan. 1934. Ibid., littoral, on the shores of I. Bartolome, 

 near I. San Salvador, no. 34-340, 23 Jan. 1934. 



Lithophyllum trichotomum (Heydrich) Lemoine 



Heydrich 1901, p. 538 (as Ltthothamnion trichotomum) ; Lemoine 

 1929, p. 45 ; Dawson 1944, p. 267, pi. 58, figs. 1, 4-6. 



For the aspect of this plant one has only the figures which Dawson 

 gives, but fig. 1 (loc. cit.) is of type material. Foslie's monograph does 

 not mention this species name. Size of the cells is a feature depended on 

 to distinguish this from L. bracchiatum, which Lemoine (1929, p. 44) 

 also records from Panama, but which has cells about half as long, or less ; 

 in this material they reach 40 /x. 



Mexico : Is. Revilla Gigedo, from tide pools along the shore of Sul- 

 phur Bay, L Clarion, no. 39-47 A, 17 Mar. 1939. 



Lithophyllum amplostratum n. sp.^*'* 

 Plate 43 



Plants moderately large, forming clumps several centimeters in 

 diameter and 2-4 cm thick; basal crust thin, commonly destroyed; erect 

 branches moderately crowded, below freely anastomosing, above free, 

 irregularly and erectly branched, the branches 2-6 mm diam., little 

 tapered, the ends blunt; conceptacles crowded on the outer segments, 

 slightly elevated, appearing 180-200 /x diam. and with a single pore; in 

 section tetrasporangial conceptacles deeply immersed, oval, about 160 /* 

 deep, 320 /* wide; perithallus thin, of few cell layers, cells 8-14 /x diam., 

 10-20 II long; medulla very evenly and conspicuously zonate, the zones 

 one cell deep, of somewhat varied thickness, rarely only 50 /t, generally 

 85-255 /x thick, of cells 8-13 /x diam. 



104 Lithophyllum amplostratum n. sp. — Plantae botryones aliquot cm diam., 

 2-4 cm crass, formantes; copiose irregulariterque ramosae, ramis teretibus obtusis- 

 que erectis, 2-6 mm diam.; perithallo tenui, cellulis 8-14 |x diam., 10-20 \i long.; 

 medulla manifeste zonata, zonis crassitudine unius cellulae, cellulis 8-13 \i diam., 

 50-225 \x, long, Planta typica in loco dicto I. Santa Maria, Ecuador, legit W. R. 

 Taylor no. 34-234A, 17 Jan. 1934. 



