268 



Puget Sound Marine Sta. Pub. Vol. 1, No. 25 



colorless cells. Plants single or in clusters arising from a small disc-like 

 base. 



Rare ; on stones in the lower littoral zone. 



Cymathere triplicata 



Phyllitis fascia 



24 



Punctaria latifolia 



0.25. 



PLATE 57 



Fig. 22. Diagrammatic sketch of plant. X about 0.05. 



Figs. 23 and 24. Diagrammatic sketches of the plants. X about 



15. PUNCTARIA Greville 



1. Punctaria latifolia Grev. Alg. Brit. p. 52. Fig. 24 



Plant body an undivided flat olive-green Ulva-like blade, oblong or 

 obovate, suddenly tapering below into a short stalk. Blade usually com- 

 posed of four layers of cells and covered by distinct minute dots in which 

 the sporangia are produced. Plants sometimes in groups. 

 In the lower littoral zone on other algae. 



