NO. 10 DAWSON : MARINE ALGAE. GULF OF CALIFORNIA 225 



Sphacelaria brevicorne S. & G. 



Setch. & Card., 1924, p. 725, pi. 19, figs. 59, 60. 



Brand. 59 on Sargassum, La Paz; D. 598b, on and among encrusting 

 algae in coral heads, San Gabriel Bay, Espiritu Santo Island, Februaiy. 



In describing this species Setchell and Gardner say: "Sphacelaria 

 brevicorne has very close affinity in S. cornuta Sauv. ( 1901, p. 132, repr.) 

 the type locality of which is New Caledonia. Unfortunately, we have no 

 fruit on ours. We are basing the distinction from S. cornuta largely on 

 the differences in the character of the propagula." 



D. 589b is undoubtedly of this same species but even more closely re- 

 sembles S. cornuta. The propagulum-rays are 3-4 celled and often mark- 

 edly acute, rather than "short, blunt, and of two cells," as stated in the 

 original description of S. brevicorne. Some, however, are identical with 

 the Setchell and Gardner figure. The plants are about 3 mm. high, some- 

 what larger than those of the Brandegee collection, but it is not unlikely 

 that the latter specimens are younger, the propagula not fully mature, this 

 accounting for the shorter rays and the smaller size of the whole plants. 

 For the present, the specimens on hand will be placed under the name 

 given to them by Setchell and Gardner, although this may be relinquished 

 in favor of S. cornuta as a fuller knowledge of our species is developed. 



Sphacelaria Hancockii sp. nov. 

 Plate 31, Fig, 8 



Frondes caespitosae, 8-12 mm. altae, inferne dense superne sparse ramosae; 

 ramis omnibus erectis strictisque; fills 35-60 \i diam. ; pills copiosis, 500-1000 n 

 longis; propagulis tribuHformlbus, 75-90 \i latis, 100-110 |x longis, pedlcellls 2-3 

 cellularibus suffultis et radiis inconspicuis, quibusque cellula rotunda singula aut 

 leviter protrudente aut non protrudente compositis; zoosporangiis gametangiisque 

 nondum visis. 



Erect filaments forming brown tufts on rock surfaces, 8-12 mm. high, 

 attached by a small, dense mat of rhizomes, densely branched from the 

 base, sparsely and irregularly above; all branches erect and strict; fila- 

 ments 35-60 fi in diam.; segments as broad as high, with vertical parti- 

 tions only; hairs abundant, 500-1000 /x long, of up to 10 cells, about 15 fi 

 in diam.; propagula tribuliform, 75-90 /a broad, 100-110 /a long, on 2-3- 

 celled pedicels ; rays inconspicuous, each of one rounded cell, little project- 

 ing or not at all ; zoosporangia and gametangia unknown. 



