102 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 17 



its upper side to ascending and finally erect, once- or twice-branched rows 

 of more or less quadrangular perithallus cells mostly taller than broad, 

 these perithallus cells 18-21 /a broad below, 7-9 jx broad above; tetra- 

 sporangial nemathecia superficial, elevated, about 80-100 /x thick, of 

 rather slender, clavate paraphyses of 5-7 cells; tetrasporangia narrow- 

 elliptical, about 45-50 fi long, 9-12 /a wide; sexual reproduction not 

 observed in Mexican material. 



Type: Holotype not designated and existence of original material 

 unknown to the writer. 



Type locality: Mediterranean Sea. 



Mexican distribution: Baja Calif. (Cape district) — Howell 

 728, dredged from 40 meters depth, off San Jose del Cabo, Aug. 



A comparison of the Howell collection with specimens from the 

 Mediterranean has shown them to be essentially identical in all sig- 

 nificant respects. A Japanese specimen of Peyssonelia caulifera Okamura 

 also shows very close agreement and suggests that that name probably 

 should be considered as a synonym. 



Peyssonelia pacifica Kylin 



Plate 11, figs. 3-4 



Kylin, 1925, p. 25, figs. 12B-D; Kylin, 1941, p. 8; Smith, 1944, p. 

 212, pi. 48, fig. 3. 



Thalli saxicolous, very lightly calcified, closely adherent by rhizoids 

 or by semi-penetrating cell rows, usually reflecting the irregularities of 

 the substrate, to 6-7 cm. broad, of a dark purplish-red color, the surface 

 often with a somewhat granular texture, usually without conspicuous 

 striations, 250-350 (450) /a thick; transection showing a hypothallus of 

 quadrangular cells 15-20 ju, in diameter giving rise to erect or ascending, 

 1-3 times branched rows of more or less rectangular cells decreasing up- 

 wards in diameter and height to about 4-6 ju, broad ; tetrasporangia long- 

 ovate, 40-55 ix long, 18-25 jx wide, cruciately divided, borne in super- 

 ficial, scarcely elevated nemathecial sori 1.5-3.0 mm. broad, 70-100 /a 

 deep, among dense, rather coarse, clavate paraphyses of 6-8 cells, the 

 upper ones relatively short and broad ; sexual reproduction not observed 

 in the Mexican material (see Kylin, 1925). 



Type: Holotype not designated but probably represented by 

 Kylin's original collection in the Botanical Museum, University of 

 Lund, Sweden. 



Type locality: Growing on Patella, south of False Bay, San 

 Juan Island, Washington. 



