Myxophyceae 129 



(2) Plant mass dull or dark lead-colored; Irichomes 6-14 mic. in 

 diameter, constricted at joints near apices S. hydnoides 

 2. Fascicles appressed; trichomes 1.5-3-5 mic. in diameter, especially 

 constricted at joints S. laete-viridjs 



II. Plants living on moist earth, or in fresh or hot water. 



1. Trichomes 1-3 mic. in diameter 



(i) Plant mass deep blue-green; trichomes 1.2-2 mic. in diameter, 

 sometimes constricted at joints S. thermalis 



(2) Plant mass compact, fibrous; trichomes 1.5-2.5 mic. in diameter, 



not constricted at joints S. dubia 



(3) Plant mass blue-green, changing to brown; trichomes 2-3 mic, 



in diameter S. fuscescens 



2. Trichomes 3-8 mic. in diameter 



(i) Fascicles short, erect, spine-shaped; trichomes 3.4-4 mic. in diame- 

 ter, not constricted at joints; cells somewhat quadrate or shorter 

 than the diameter S. muralis 



(2) Fascicles tapering from a broad base to a loose, somewhat peni- 



cillate apex; trichomes 5.6 mic. in diameter; cells a little longer 

 than their diameter, after division shorter S. borealis 



(3) Fascicles elongate, usually procumbent, spine-shaped; trichomes 



5-8 mic. in diameter, not constricted at joints; cells somewhat 

 quadrate or longer than the diameter S. muscorum 



348. Symploca atlantica Gomont. Monogr. Oscill. 129. pi. 2. f. 5. 1893. 

 De Toni. Syll. Algar. 5: 302. 1907. 



Collins, Holden and Setchell. Phyc. Bor.-Am. Fasc. 28. no. 1356. 1907. 



Plant mass fasciculate-caespitose, blackish green; fascicles up to i 

 cm. in height, erect; filaments very densely entangled, free, unbranched; 

 strongly and angularly twisted; sheaths thin, firm; trichomes 4-6 mic. in 

 diameter, constricted at the joints throughout entire length; outer mem- 

 brane of apical cell thickened into a depressed conical calyptra; cells 2-6 

 mic. in length; transverse walls conspicuous, pellucid, not granulated; cell 

 contents scarcely granular, greenish yellow. 



California. On ground moistened by salt water. Bay Farm Island, near 

 Alameda. November 1905. (Gardner). 



249. Symploca hydnoides Kuetzing. Spec. Algar. 272. 1849. Gomont. Mon- 

 ogr. Oscill. 126. pi. 2. f. 1-4. 1893. De Toni. Syll. Algar. 5: 300. 1907. 

 Schramm and Maze. Essai Class. Algues Guadeloupe. 29. 1865. (S. a n- 

 t ill arum Crouan). Maze and Schrjmim. Essai Class. Algues Guade- 

 loupe. 18. 1870-1877. (O. hydrurimorpha Crouan, O. symplocari- 

 o i d e s Crouan). Murray. Catalogue of the Marine Algae of the West 

 Indian Region. Journ. of Bot. 27: 261. 1889. Collins, Holden and Setchell. 

 Phyc. Bor.-Am. Fasc. 3. no. 203. 1895. Collins. Preliminary Lists of New 

 England Plants.— V. Marine Algae. Rhodora. 2: 43. 1900; Phycological 

 Notes of the late Isaac Holden. — II. Rhodora. 7: 222. 1905. Vickers. Liste 

 des Algues Marines de la Barbade. Ann. Sci. Nat. Bot. VIII. i: 55. 1903. 



