438 BULLETIN OF THE BUREAU OF FISHERIES. 
Frond 1.5 to 4 cm. tall, forming muddy, dirty-looking tufts; branches spreading, usually short; 
diameter of filaments 15 to 34 mic., lower cells 2 to 3 diameters long, median ones 1 to 1.5 diameters, 
apical ones 3 to 4 diameters; sporangia of both kinds occurring on the same individual; ‘‘unilocular 
sporangia’’ ovate, sessile; “‘plurilocular sporangia’ clavate, broad, obtuse or truncated at the apex, 
sessile, divided into numerous cells zonately arranged. 
West Indies; Guadeloupe. 
Fairly abundant on marine grasses, Newport River, near Green Rock, Beaufort, N. C., August, 1906. 
Fig. 7.—Ectocarpus duchassaingianus, “plurilocular spo- Fig. 10.—Ectocarpus mitchelle, “plurilocular sporangia,’’ 
tangium,”’ X 279. 
Fig. 8.—Ectocarpus siliculosus, “plurilocular sporangium,” 
X 279. 
Fig. 9.—Ectocarpus confervoides, “plurilocular sporangia,’”’ 
X 279. A, Sessile; B, Shortly pedicellate. 
279. 
Fig. 11.—Ectocarpus sp. from coral reef, 1914, “ plurilocular 
sporangium,” X 279. ‘ 
This species can be distinguished from the others occurring at Beaufort by its small size, muddy 
appearance, tufted branches, and the shape of “plurilocular sporangia.’’ 
This is the northern limit reported for the species. 
2. Ectocarpus siliculosus (Dillwyn) Lyngbye. Fig. 8. 
Conferva siliculosa, Dillwyn, 1809, Supplement, p. 60, pl. F. 
Ectocarpus siliculosus, Lyngbye, 1819, p. 131, pl. 43 C (excluding var. 6 and synonyms). 
Ectocarpus viridis, Harvey, 1852, p. 140, pl. 12 B, C. 
Ectocar pus confervoides var. siliculosus, Farlow, 1882, p. 71. 
Ectocarpus siliculosus, De Toni, 1895, p. 549. 
P. B.-A. Nos. 319, 1386, 2294. 
Fronds 3 to 30 cm. long, yellowish or from brownish to olivaceous, forming flaccid tufts, attached 
or floating free; branching distinctly lateral or pseudodichotomous below; branches alternate or uni- 
