NO. 1 TAYLOR: PACIFIC MARINE ALGAE 169 



Peyssonnelia calcea Heydrich, prox. 



Plant crustose, forming irregular disks more than 5 cm diam., the 

 margin lobed, the surface dull, brownish or yellowish when dry with 

 darker glutinous spots; moderately closely adherent without any free 

 lobes, but readily cracking off the rocky substratum when dry ; the lower 

 portion firmly calcified, only the upper perithallus free from lime ; thick- 

 ness to 450 IX, composed of a hypothallus about 60 fj. thick including a pro- 

 nounced lower cuticle, of one cell layer, the cells subequal to much taller 

 than broad, about 30 /a long and the narrowest columnar, 15 ju, wide, this 

 layer on the under side covered with very many short, rather straight 

 rhizoids 15 /x, diam.; perithallus of cell rows about 15 /a diam., sparingly 

 divided and the cells considerably taller than broad below, but near the 

 surface much more closely divided, the last 2-3 tiers of small cells about 

 6-7 /x wide and 4-5 fi tall, but the surface layers on some tiers replaced 

 by darker and rounded cells about 12-18 ft diam., rather abundant and 

 giving a characteristic appearance in surface view; sporangia in small sori, 

 red, oval, tetrapartite, 55-72 ju, long, 22-35 ft diam. 



Mexico: Is. Revilla Gigedo, dredged from 37 meters' depth at sta. 

 132, Braithwaite Bay, I. Soccoro, no. 34-41, 2 Jan. 1934. 



CRUORIELLA Crouan, 1859 



Plant crustose, attached to the substratum by rhizoids on the under 

 surface, the thallus composed of a lower layer or hypothallus and an upper 

 layer or perithallus, the hypothallus of radiating filaments in small fan- 

 shaped groups, the perithallus of erect filaments united by a matrix; spo- 

 rangia tetrapartite, in sori. 



Gruoriella Dubyi Crouan, prox. 



This material appears to be close to, if not identical with, that issued 

 in Phyc. Bor.-Amer. no. LVII from Pacific Beach, Calif., as Peyssonnelia 

 Dubyi. 



Mexico: Is. Revilla Gigedo, rare as dredged from 37 meters' depth 

 at sta. 132 off Braithwaite Bay, I. Soccoro, no. 34-40A, 2 Jan. 1934. 

 Ibid., rare on coral fragments from tide pools, Sulphur Bay, I. Clarion, 

 no. 39-8, 16 Mar. 1939. Ibid., rare on shells dredged from 50-75 meters' 

 depth at sta. 917 off Sulphur Bay, no. 39-28 A, 16 Mar. 1939. Nayarit, 

 occasional on Lithothamnieae growing on Pontes coral in littoral pools, 

 I. Isabel, no. 34-589 A, 3 Mar. 1934. 



