316 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 3 



pletely corticated above; internodes naked below but shorter than the 

 corticated zones at the nodes ; corticating cells not arranged in any defi- 

 nite order; tetrasporangia completely immersed, irregularly placed in 

 the swollen, often once- or twice- forked terminal ramuli; tetrasporic 

 branches at maturity usually with one or two sharp points; cystocarps 

 sessile, surrounded by 6-8 ramuli ; antheridia completely covering upper, 

 several-times-forked, somewhat swollen ramuli. 



With more adequate material on hand it has been possible to interpret 

 the types of Ceramium sinicola and C. bicorne more fully. The compari- 

 sons show that the two sharp, apical points used in distinguishing C. 

 bicorne are not specific. There may be from one to three, quite at random 

 and depending upon certain features of the individual plant. In review- 

 ing the type of C. sinicola, the presence of tetraspores "in a single whorl 

 at the nodes" can be interpreted as such only in young branches. The 

 irregularity of placement is generally as great as in the type of C. bicorne. 



These plants are epiphytic, commonly on Codimn and Grateloupia. 

 Tetrasporic plants have been detected from collections made at various 

 seasons through the year. 



D. 444, San Esteban Island, Feb.; D. 298c, Puerto Refugio, Jan.; 

 D. 389, Tepoca Bay, Feb.; D. 162, 127, 134, 128, Turner's Island, 

 Jan.; J. 67b, Ensenada Bay, April; J. 62a, Isla Partida, July; D. & R. 

 3231a, 3411a, Guaymas, Dec. 



Ceramium sinicola var. interruptum (S. & G.) comb. nov. 



Ceramium interruptum Setch. & Gard., 1924, p. 775, pi. 26, fig. 47. 



The Setchell and Gardner illustration does not satisfactorily interpret 

 the specimen from which it was drawn. The material of Marchant's col- 

 lection is similar in all general respects to the specimens of C. sinicola 

 investigated. It differs in the marked interruption in cortication just above 

 the forkings. This character has been sought for through the specimens 

 of C. sinicola, and, though nowhere else so prominent, a more or less 

 strong tendency toward a cortical break in this region is present in most 

 of them. Marchant's specimens appear, then, to be extreme types of this 

 complex and, lacking other well-defined points of distinction, should 

 better be considered as a variety of C. sinicola. 



Epiphytic on other algae, M. 78, Eureka, May. 



Ceramium sinicola var. Johnstonii (S. & G. ) comb. nov. 



Ceramium Johnstonii Setch. & Gard., 1924, p. 774, pis, 76, 77. 



This is another form of the sinicola complex which is fundamentally 

 inseparable from the general assemblage. The type specimen is a robust 



