40 Allan Hancock Pacific Expeditions vol. 26 



Thalli partim endophytici, e filamentis profunde inclusis, cellulis 30 fi 

 diam., 100-150 /x long, constantes; filamenta inter utriculos Codii remote 

 alterne ramosa, ad superficiam filamenta 500-800 fi long, libera brevia erecta 

 ramosa producentia; filamenta libera irregulariter semel vel bis alterne aut 

 subdichotome ramosa, non in eodem piano, e cellulis plerumque 1.0-1.5 plo 

 longioribus quam latae composita, haud attenuata, cacuminibus obtusis; 

 polysporangia subspherica aut ovata, ad 100 n long., 12-18 sporas habentia, 

 reproductio sexualis non visa. 



Thalli partly endophytic, consisting of deeply embedded filaments, 

 with cells 30 \x in diam., 100-150 /x long, ramifying between Codium 

 utricles, remotely alternately branched, at the surface producing short, 

 erect, branched, free filaments 500-800 /x long; free filaments irregularly 

 once or twice alternate or subdichotomous, not in one plane, of cells 

 mostly 1.0-1.5 diameters long, not at all attenuated, the tips blunt; 

 polysporangia subspherical or ovoid, to 100 /x long, with 12-18 spores; 

 sexual reproduction not seen. 



Type: Holotype is E. Y. Dawson 8318, December 18, 1949, in 

 Herb. A. Hancock Foundation; an isotype slide is in Herb. Beaudette 

 Foundation. 



Type locality: Endophytic in Codium fragile, intertidal, extreme 

 south tip of Isla Guadalupe, Baja California, Mexico. 



Pleonosporium dasyoides (J. Ag.) G. DeToni 

 PL 13, fig. 1-2 

 G. DeToni, 1903, p. 1310; Kylin, 1941, p. 28; Dawson, 1946c, p. 83; 

 Callithamnion dasyoides J. G. Agardh, 1876, p. 31. 



Thalli 5-10 cm. tall, usually epiphytic (sometimes on hydroids, etc.), 

 alternately more or less distichously branched, the upper main branches 

 from the primary axis often longer than the lower ones; primary axes 

 and branches of first and second orders corticated by slender, branched, 

 descending rhizoidal filaments from the basal cell of lateral branches; 

 primary axes 300 /x in diam. or more, to 1 mm. near the base; 

 ultimate indeterminate branchlets of 11-16 cells about as long as broad, 

 about 40 [x in diam. at the base, somewhat tapered, more or less 

 adaxially curved, terminally blunt; polysporangia terminal on simple 

 or compound branchlets of 1-several cells from near the base (adaxial, 

 sometimes also abaxial) of determinate laterals, elliptical, about 65-75 [x 

 long; spermatangia forming a terminal subcylindrical or subconical 

 compact cluster on ultimate branchlets, the sterile base of 1-3 cells. 



Type: Not specifically designated, represented by at least 2 

 specimens in Agardh Herbarium, Lund, Sweden. 



Type locality: Not specifically designated, indicated as "Chile" 

 and "California." The type of the California plant is represented by a 

 specimen marked Callithamnion dasyoides 6 californicum without 

 definite locality. 



Mexican distribution: Pacific Baja Calif. — D. 173-45, Punta 



