VOL. 5] Notes on Alga. 127 



periphery, finally dying away at the center, but the margins 

 continuing to grow and to extend, reaching a diameter of from 

 30 to 40 cm., thick, dull red in color, distinctly zonate, the erect 

 fronds arising at the margins in considerable numbers, but be- 

 coming intramarginal as growth proceeds; structure of the pros- 

 trate frond of rounded colorless thin-walled cells which become 

 narrower and more elongated above. Erect frond gregarious, 

 short (up to 8 cm. in length), at first obovate and entire, later 

 usually divided, even to the very base, into several narrow, 

 cuneate or spatulate segments; color dark red to almost black 

 above, lighter below. Tetraspores and cystocarps unknown. 



Gregarious on boulders along the beach near Helmet Rock, 

 Land's End, San Francisco, in the middle of the littoral zone. 

 Distributed as Sarcophyllis Californica f. pygmcea Setchell, in Col- 

 lins, Holden, and Setchell, Phyc. Bor.-Amer., No. 396. It is 

 very similar to Dilsea Californica (J. Ag. ) Schmitz, but is smaller, 

 thicker, and with characteristic horizontal thallus. 



Constantinea simplex Setchell mss. Low, simple or once 

 forked, solitary or, at times, decidedly gregarious; stem 2 to 6 cm. 

 long, 6 to 12 mm. in diameter, stout, annulate with the scars of 

 fallen blades, the scars crowded, there being always much less 

 than the diameter of the stem between any two adjacent ones. 

 Blade, one, or occasionally two, on the same stem or branch, 

 orbicular, 6 to 12 cm. in diameter, thick, fleshy, dull red, either 

 entire, or soon splitting, more or less deeply, into several seg- 

 ments, the new blade appearing as a delicate saucer-shaped mem- 

 brane in the center of the old one and gradually expanding and 

 thickening. Tetrasporangia in irregular, extended, more or less 

 confluent nemathecia or sori, which form a distinct zone from the 

 margin towards the center, about two-thirds of the radius, zonate 

 (with more or less oblique divisions) scattered among simple, 

 slender, more or less clavate, unicellular paraphyses. Cysto- 

 carps closely crowded, in a zone similar in extent to that 

 occupied by the sori; centripetal, in development, situated in the 

 inner cortex of the upper surface of the blade, opening outward 

 through the outer cortex of the upper surface by small pores, 

 with gonimolobes confluent at maturity and separated slightly by 



