1919] Setchell-Gardncr : Myxophyceae 81 



Species of Symploca maj' usually be readily recognized by tlieir 

 habit of occurring in more or less extended layers with the filaments 

 at first prostrate, but soon forming erect fascicles which give the sur- 

 face the effect of ])eing covered b}- more or less crowded tooth-like 

 tufts. In certain stages, however, and even under certain conditions, 

 these fascicles are not formed. In such cases it may be difficult to 

 distinguisli the species from those of Phormidium. The symplocoid 

 habit is also found in certain species of Schizothrix, Scijtonema, and 

 Calothrix, and one of us ("W. A. S.) has found, particularly among 

 thermal algae, undoubted species of Phormidium assuming a symplo- 

 coid habit under certain conditions. 



Key to the Species. 



1. Apical cell rounded, not calyptrate 2 



1. Apical cell convex, calyptrate 3. S. aeruginosa (p S3) 



2. Apical cell slightly swollen, trichomcs 6-8/a thick 1. S. hydnoides (p 81) 



2. Apical cell not at all swollen, trichonies 3-3. 5/^ thick 



2. S. funicularis (p 82) 



1. Symploca hydnoides Kuetz. 



Plate 1, figs. 12, 13 



Filaments forming erect, sordid, or dark blue-green, sharply 

 pointed fascicles, 1-2 cm. high, in age often discolored at the base, 

 sparingly- false branched; sheaths thin, slightly mucous; trichomes 

 blue-green, 6-8/i, diam., slightly torulose near the apex ; length of cells 

 variable, 5-14/a long; protoplasm filled with large granules, par- 

 ticularl}^ near the cross walls; apical cell slightly inflated, without 

 calyptra. 



Growing on logs in the littoral belt. Whidbey Island, Washington. 



Kuetzing, Sp. Alg., 1849a, p. 272; Gomont, Monogr. des Oscill., 

 1892, p. 107, pi. 2, figs. 1-4 (1893, p. 126, Repr.) ; Setchell and 

 Gardner, Alg. N.W. Amer., 1903, p. 188 ; Collins, Ilolden and Setchell, 

 Phyc. Bor.-Amer. (Exsiec), no. 905 (under var. genuiim Gomont). 



We have retained the name Symploca hydnoides for this species, 

 since this was the final decision of Gomont. We note, however, that 

 Gomont {loc. cit., p. 108; p. 129 of Repr.) states that the first name 

 given to this species was Blennothrix elegant Kuetz. (1845, p. 181) 

 and that this was referred by Kuetzing later (1849rt, p. 272) to 

 Symploca as S. elegans. In the same account (1849o, p. 270), how- 

 ever, occurs also a description of the earlier Symploca elegans Kuetz. 

 described in 1843 (p. 201). In the Tabulae Phycologicae (vol. 1, 



