MARINE ALG OF BEAUFORT, N. C. 437 
and possibly small gametes(?). Occasionally gametes, either male or female, may 
germinate without fusion. In addition to these, aplanospores may be formed in the 
“plurilocular sporangia.”” Both “unilocular’’ and ‘“‘plurilocular’’ sporangia are formed 
in special branches or in portions of ordinary branches. 
KEY TO GENERA. 
Basal portion of the frond a filament expanded on the surface of the substratum; sporangia 
PORE MEG EUS eciale PEACHES eteraleve tic elefetereinie nis Meissner sect araleine teers erie 1. Ectocarpus (p. 437). 
Basal portion of the frond a filament penetrating within other alge............ 2. Streblonema (p. 440). 
Frond consisting of horizontal, more or less crowded, filaments, forming irregular or some- 
what disklike patches on the surface of the host............---2....000.. 3. Pheostroma (p. 442). 
Genus 1. Ectocarpus Lyngbye. 
Ectocarpus, Lyngbye, 1819, p. 130. 
Thallus consisting of few or many simple or branched upright filaments arising from 
a horizontal filament; attached to substratum by the horizontal filament, often assisted 
by rhizoidlike processes from the bases of the upright filaments; longitudinal growth in 
the upright filaments intercalary, in the horizontal filaments apical; filaments usually 
monosiphonous, very rarely polysiphonous by longitudinal walls here and there; asexual 
Propels a by laterally biciliate zoospores and nonmotile aplanospores produced in 
“unilocular sporangia;’’ sexual reproduction by laterally biciliate motile gametes, 
similar or differing in size, etc., produced in “plurilocular sporangia;’’ both organs of 
fructification occurring in the place of branches, always singly, usually on different 
individuals, sometimes apparently on the same individual; “unilocular sporangia’’ 
usually globose, ellipsoid, or short pyriform, sessile or shortly pedicillate, opening by an 
apical pore; “plurilocular sporangia’’ various in form, usually ovoid or silique form, or 
narrowly subuliform, sessile, or pedicillate, usually opening by an apical pore, sometimes 
tapering at the apex to a segmented hair. 
Numerous species described, but many on insufficient characters, about 40 to 70 
recognized; in all seas, especially the North Atlantic. 
An extremely difficult genus which has not yet received sufficient study to establish 
order among the innumerable forms occurring init. One not familiar with the genus can 
scarcely hope to determine the species. Fruiting specimens are always necessary. The 
fruits are microscopic. 
KEY TO SPECIES. 
a. Frond 2 to 5 cm. tall, rarely more; ‘“‘plurilocular sporangia’’ clavate, broad, obtuse or 
EnMICALeg Ab SNe ABE XS SE SSCL coe cision telat alee ela 1. E. duchassaingianus (p. 437). 
Ga. MYON SHALLY, 6 LOO CM ANG NOME LAU: cree eciacec ce Cece cian eee tee Per ne ct ore See OO eee ES b. 
b. “Plurilocular sporangia’’ conical-subulate, rarely short ovate, often tapering to a hair 
EE Ae Oe BE ee arene am pri tae ichoraaeiner cerita be tcidicashe 2. E. siliculosus (p. 438). 
bb. “ Plurilocular apeEABI short subulate or fusoid, not iis to a. hair 
ost lenale ..3. E. confervoides (p. 439). 
bbb. « Plurilocilar spordaseiast Ioelitpticad Obie obtuscs U okid Qaaes Gta » 4. E. mitchelle (p. 439). 
1. Ectocarpus duchassaingianus Grunow. Fig. 7. 
Ectocarpus duchassaingianus, Grunow, 1867, p. 45, pl. 4, £. z- 
Ectocar pus duchassaingianus, De Toni, 1895, D. 54s- 
P. B.-A. Nos. 985, 2077. 
