428 BULLETIN OF THE BUREAU OF FISHERIES. 
One of the largest genera of alge and one of the most difficult. There are few 
sharply marked characters for distinguishing the species, it being mostly a question of 
more or less in one respect or another. It is impossible for one not familiar with the 
genus to determine the species without abundant authentic specimens for comparison. 
KEY TO SPECIES. 
a. Main’ filaments seldom’ reaching 150 mic. in diameter. / 00. on. eee cee cnet cere esses eeesns b. 
b. Main filaments distinctly angled or flexuous | 1.22.00) 00.02 1. C. flexuosa (p. 428). 
bb.| Main filaments straight or nearly so... ov. 650...) ye ee 2. C. crystallina (p. 428): 
aa. Main filaments 1§6,mic..or more in diamteter.).)... 2) errs akettkaeh-usde Miss ore eaeloee etaapae eels ¢. 
c., Lower cells less thanvro diameters Jong. oo. Sian shes anc Bane poh = 3. C. fascicularis (p. 428). 
cc. Lower cells ro diameters long or more...................- BOB Sits Wee 4. C. prolifera (p. 429). 
1. Cladophora flexuosa (Mueller) Harvey. 
Conferva flexuosa, Mueller, in Flora Danica, tom. s, pl. 882, 1782. 
Cladophora flexuosa, Harvey, 18492, Dp. 202. 
Cladophora flexuosa, Harvey, 1858, p: 78. 
Cladophora flexuosa, Farlow, 1882, p. 54. ' 
Cladophora flexuosa, De Toni, 1889, p. 311. 
Cladophora flexuosa, Collins, 1909, p. 339. 
A. A. B. Ex. No. 206. 
P. B.-A. Nos. 1076, 1527, 2239. 
Fronds 10 to 20 em. high, light green; main filaments 80 to 120 mic. diameter, regularly flexuous 
with flexuous alternate branches, 40 to 80 mic. in diameter, with alternate or secund, curved, and some- 
times refracted ramuli; cells from 6 diameters long below to 2 diameters in the ramuli. 
Newfoundland to Bermuda and Florida; Alaska; Europe. 
Abundant, attached and floating masses, Mullet Pond, Shackleford Banks, and fairly abundant 
on rocks of Fort Macon jetties, Beaufort, N. C., about low-water line, April, 1908. 
This species closely approaches several others of the genus, but as none of these similar species has 
been found at Beaufort, this fact need not give trouble there. Of the Beaufort species, it most nearly 
resembles C. crystallina, from which it is distinguished by its flexuous, alternate branches. It has been 
observed at Beaufort only in April, 1908, not being found there in May, 1907, and not being present in 
Mullet Pond in August, 1907. 
2. Cladophora crystallina (Roth) Kuetzing. Pl. uxxxiv, fig. 1. 
Conferve crystallina, Roth, 1797, p. 196. 
Cladophora crystallina, Kuetzing, 18454, p. 213. 
Cladophora crystallina, De Toni, 1889, p. 318. 
Cladophora crystallina, Collins, 1900, p. 342. 
P. B.-A. Nos. 1581, 1865. 
Fronds yellowish or whitish green, soft, glossy, ro to 30 cm. high; filaments slightly matted, dis- 
tantly dichotomously or trichotomously branched; main branches 80 to 140 mic. in diameter, tapering to 
25 to go mic, in the ramuli; branching erect or patent; upper ramuli sometimes whorled or alternately 
secund; cells cylindrical, 4 to 12 diameters long. 
Massachusetts; West Indies; Bermuda; Europe. 
Abundant on sea buoy, Beaufort, N. C., July, 1907. 
A variable species, but usually marked by its light color and silky gloss. It is distinguished from 
C. flexuosa, the Beaufort species which it most nearly resembles, by its dichotomous or trichotomous 
branching and its straight branches. 
3. Cladophora fascicularis (Mertens) Kuetzing. 
Conferva fascicularis, Mertens, in Agardh, 1824, p. 114. 
Cladophora fascicularis, Kuetzing, 1843, p. 268. 
Cladophora fascicularis, De Toni, 1889, p. 316. 
Cladophora fascicularis, Collins, 1909, p. 345. 
P. B.-A. Nos. 122, 1228, 1472. 
