Myxophyceae 131 



Plate V. fig. SI. 



Plant mass fasciculate-caespitose, widely expanded, dark blue-green; 

 fascicles up to i mm. in height, erect, approximate, somewhat thick; fila- 

 ments sometimes branched, fragile, twisted and densely entangled at the 

 base, above parallel, curled, closely crowded; sheaths very thin, sometimes 

 mucous; trichomes 1.2-2 mic. in diameter, here and there constricted at 

 joints; apex of trichome not tapering; apical cell rotund; calyptra none, 

 cells 1.7-S mic. in length; transverse walls inconspicuous, sometimes marked 

 by two protoplasmic granules; cell contents homogeneous, rarely slightly 

 granular, pale blue-green. 



Canada. Forming extensive layers or knob-like masses on bottom of 

 ditch. Natural Sulphur Springs, Banflf, Alberta. August 1897. (Tilden). 

 New York. Adhering to bricks and stones in hot water from condensers 

 of steam engines of the water works. Schenectady. June 1893. (Holden). 



252. Symploca dubia (Naegeli) Gomont. Monogr. Oscill. 135. 1893. De 



Toni. Syll. Algar. 5: 308. 1907. 



Plate V. fig. 52. 



Plant mass compact, fibrous, widely expanded, fasciculate on the sur- 

 face, yellowish, blue-green or gray, sometimes reddish on the surface, light- 

 er colored within on account of empty sheaths; filaments coiled, entangled 

 at the base, forming parallel fascicles; sheaths somewhat thick, firm, ir- 

 regular in outline; trichomes 1.5-2.5 mic. in diameter, not constricted at 

 joints; apical cell rotund; calyptra none; cells 3-8 mic. in length; trans- 

 verse walls inconspicuous, sometimes marked by two granules; cell con- 

 tents showing protoplasmic granules arranged in lines, pale blue-green. 



Mexico. (Miiller). 



253. Symploca fuscescens (Kuetzing) Rabenhorst. Fl. Eur. Algar. 2: 153. 



1865. De Toni. Syll. Algar. 5: 307. 1907. 

 Wolle. Fresh Water Algae. Bull. Torr. Bot. Club. 6: 283. 1879; Fresh- 

 Water Algae U. S. 304. pi. 205. f. 8-12. 1887. 



Plant mass blue-green, changing to brown; fascicles mucous, penicil- 

 la^fSV'iKe apex, obtuse; filaments agglutinated; sheaths mucous, scarcely 

 ■iijjicUOtt'S;'- tells somewhat quadrate; cell contents homogeneous or finely 

 |1f«la^?^a)e' olive or yellowish blue-green. 



^h^ylvania. "Diameter of trichomes 2-3 mic.'' (Wolle). 



254. Symploca muralis Kuetzing. Phyc. Gen. 201. 1843. Gomont. Monogr. 



Oscill. 132. pi. 2. f. 10. 1893. De Toni. Syll. Algar. 5: 304. 1907. 

 Setchell. Notes on some Cyanophyceae of New England. Bull. Torr. 

 Bot. Club. 22: 429. 1895. Collins. Flora of the Blue Hills, Middlesex Fells, 

 Stony Brook and Beaver Brook Reservations of the Metropolitan Park 

 Commission, Massachusetts. 127. 1896. 



Plate V. fig. 53- 



Plant mass continuous, widely expanded, shaggy, dark lead-colored; 

 fascicles up to 2 mm. in height, spine-shaped, somewhat thick, erect; fila- 

 rr.ents elongate, twisted, irregularly entangled, closely crowded, decumbent 



