6 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL.17 



Type locality: Epiphytic on Polysiphonia urceolata in depths of 

 11-15 m., M</)llegrund, about 3^ mile off Hirshals, north Denmark. 



Mexican distribution: Pacific Baja Calif. — D. 87-45, (in Herb. 

 U. C.) on Cladophora, Punta Descanso, Apr.; D. 9169, on Porphyra, 

 Bahia Asuncion, Apr. Gulf of Calif. — D. 126-40, on Valoniopsis, Isia 

 Turner, Jan. (monosporangial) ; D. 402a-40, on Polysiphonia, Isia 

 Pond, Feb. ; Johnston 32a, on Dictyota, Isia Tortuga, June. 



Erythropeltis discigera (Berthold) Schmitz 



Schmitz, 1896, p. 313, fig. 195; Dawson, 1944, p. 252; Kylin, 1937, 

 p. 44, figs. 19A-C. Erythrotrichia discigera Berthold, 1882, p. 25, pi. 1, 

 figs. 15-18. 



Thalli epiphytic, prostrate, discoid, expanded to 0.2-0.3 mm. in 

 diameter on flat surfaces, or encircling cylindrical parts of small algae, 

 monostromatic, parenchymatous, with irregular margins ; cells irregular- 

 ly placed, polygonal, subisodiametrical, some of those of the central part 

 of the disc projecting above the surface as short filaments; chromato- 

 phores single, parietal ; monosporangia globose, cut off from the originat- 

 ing cell by an oblique wall. 



Type: Holotype not designated. Syntypes not at the Zoological 

 Station, Naples, Italy, and whereabouts unknown to the writer. 



Type locality: Epiphytic on Cystoseira abrotanifolia and on 

 Posidonia, Gulf of Naples, Italy. 



Mexican distribution: Gulf of Calif. — D. 686-40, a few discs 

 encircling filaments of Sphacelaria, Isia Tiburon, July. The possible 

 immaturity of the specimens makes this a tentative determination. 



Erythrotrichia ascendens sp. nov. 

 Plate 1, fig. 6 



Thallis 400-600 /x altis, sursum curvatis a filamento repenti, 3-6 

 cellulato ; haud ramosis, diametro ad utrumque terminum decrescentibus, 

 super infraque uniseriatis, irregulariter bi- vel tetraseriatis, in partibus 

 mediis 20-24 /x crassis. 



Thalli epiphytic, 400-600 ix high, attached at first by a basal cell, 

 later by a 3-6-celled creeping filament developing from it, consisting of 

 an unbranched (or rarely branched?), usually curved, cylindrical, erect 

 frond tapering at either end, 14-15 ju thick at the uniseriate base and 

 apex, 20-24 /a thick in mid-parts which are irregularly bi- or tetraseriate ; 

 reproduction not clearly observed, but apparently by monospores cut off 

 in the thickened mid-parts. 



