336 University of California Publications in Botany [Vol. 



Myrionema minutissimum sp. nov. 



Plate 34, figures 1-3 



Froiulil)us pulviiiulos iiicoiispicnos. 0.75-1.5 mm. diam.. for- 

 maiilibus; parte prostrata filamentis dense compactis, re^ulariter 

 radiantilnis eomposita; filamentis erectis dense stipatis, eylindricis, 

 omnibus fruetiferis; pilis veris ignotis; eellulis filamentorum repentium 

 4/u, diam., in centre frondis, quadratis, ad margines leviter longioribus 

 quam latis; eellulis filamentorum erectorum sirailibus iis repentium; 

 zoosporangiis et "aseocvstis" ignotis; gametangiis pedieellis 4-8- 

 cellulis eompositis sufifultis, eylindricis, dense stipatis, 34-40|Li longis, 

 4-4.5/i, latis. 



Growing on the cysts of Egrcgia Menziesii. Cast ashore near the 

 "ClifY House," San Francisco, California. Type, Gardner, no. 4123& 

 (Herb. Univ. Calif., no. 207020), November. 



Myrionema minutissimum may be distinguished by the absence of 

 sterile erect filaments and hairs, and by the small sized, very densely 

 crowded pedicellate gametangia. Thus far no "ascocysts" nor zoo- 

 sporangia have been observed. In its phylogenetic relationship it would 

 seem to stand equally close to M. corunnae and M. foecundum, differ- 

 ing from each, however, in details of measurements. The erect fila- 

 ments are of the same diameter at their bases as the length of the cells 

 in the creeping filaments. Since the lower part of each remains sterile, 

 it gives the mass of cells the appearance of being parenchymatous. 



Myrionema foecundum f. simplicissimum forma nov. 



Plate 33, figures 9', 10 



Frondibus pulvinulos orbiculares, 0.5-1.5 mm. diam. formantibus; 

 parte prostrata filamentis regulariter radiantibus et arete adhaeran- 

 tibus augmentatione ramificationeque apicali eomposita ; filamentis 

 erectis omnibus fruetiferis; pilis veris ignotis; eellulis filamentorum 

 repentium 3-4. 5|a diam., medio quadratis, prope marginem 2-plo 

 longioribus; zoosporangiis ignotis; "ascoeystis" raris usque ad numer- 

 osis, elavatis 28-34ju, altis; gametangiis transformatione filamenti omnis 

 quisque erectiis marginis frondis exceptis oriendis, 30-40/x altis. 7-9/i 

 latis. 



Growing on the sporophylls of Nereocystis Luetkcana. Puget 

 Sound, Washington, to central California. Type, Gardner, no. 4316 

 (Herb. Univ. Calif., no. 207022), Moss Beach, San Mateo County, 

 California, July. 



We have not seen either the type or any other authentic material 

 of Phycocelis foccunda Stroemfelt. Neither have we anv authentic 



