234 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 12 



Ecuador: Archipielago de Colon, dredged from 27 meters off Post 

 Office Bay, I. Santa Maria, no. 34-280 A (tetrasporic, cystocarpic), 19 

 Jan. 1934. Ibid., dredged from 12-18 meters, no. 34-360 (cystocarpic, 

 TyP£),27Jan. 1934. 



Gracilaria tenuifolia n. sp.^^^ 

 Plate 78, Fig. 1 



Plants to 15 cm tall, bright rose red, thin, crisply membranous-fleshy 

 in texture, near the base slender and compressed, gradually widening to 

 the blade which is rather irregularly 7-10 times dichotomously or occa- 

 sionally polychotomously divided, the segments narrow, below somewhat 

 cuneate, above more strap shaped, to 5 mm broad above the 20°-60° 

 forks, the sinuses slightly rounded, the apices a little more narrow, obtuse ; 

 to 130-260 /x thick, structurally showing a medulla of 2-3 layers of very 

 large thin-walled cells and a cortex of 1-2 layers of small close-placed 

 cells, each about 6-8 fi deep and as broad or somewhat broader ; sparingly 

 proliferous, the branchlets with slender bases and at first ligulate but later 

 branching like the parent plant ; sporangia tetrapartite, scattered over the 

 upper branches below the final fork, prominent in the thin cortex, 25-35 

 IX diam. ; cystocarps very prominent, entirely above the general thallus 

 surface, showing a contracted base and a pericarp considerably thickened 

 near the top, with a pore, the carpospore mass covering a large sterile 

 basal tissue which is connected by occasional filaments with the pericarp. 



Dawson's Gracilaria veleroae (1944, p. 297, pi. 70, fig. 2 in part) 

 may represent a less luxuriant phase of this same plant, but one cannot be 

 sure from his description, particularly since the orientation of the cortical 

 cells is not clearly stated. 



Mexico: Is. Revilla Gigedo, abundant as dredged at sta. 129 from 

 25-32 meters off Braithwaite Bay, I. Soccoro, no. 34-13 (tetrasporic and 

 cystocarpic, TYPE), 2 Jan. 1934. Ibid., rare as dredged at sta. 135 

 from 45 meters' depth off Sulphur Bay, I. Clarion, no. 34-47 (cysto- 

 carpic), 5 Jan. 1934. Ibid., dredged from 41-84 meters' depth at sta. 

 924, no. 39-68, 18 Mar. 1939. Ibid., dredged from 51-79 meters' depth 

 at sta. 917, no. 39-23, 16 Mar. 1939. Ibid., dredged from 45 meters' 

 depth at sta. 919, no. 39-33, 17 Mar. 1939. Ibid., dredged from 56-102 

 meters' depth at sta. 921, no. 39-39, 17 Mar. 1939. 



141 Gracilaria tenuifolia n. sp. — Plantae ad 15 cm altitudine, infra compressae, 

 supra dilatatae in laminam 7-10 dichotome aut polytome furcatam, segmentis 

 angustis, paululum cuneatis ad ligulata, ad 5 mm latitudine, apicibus paululum 

 angustatis, obtusis; planta tenui et crispate membrano-succulenta; medulla con- 

 stante e 2-3 stratis cellularum magnarum, parietes tenues habentium, cortice ex 1-2 

 stratis cellularum parvarum confertarumque constante. Planta typica in loco dicto 

 Braithwaite Bay, Soccoro I., Mexico, legit W. R. Taylor no. 34-13, 2 Jan. 1934. 



