THE GREEN ALGAE OF NORTH AMERICA 5 



3. C. PYRIFORMIS (A. Br.) Borzi, 1894, p. 153 ; G. M. Smith, 

 igi6b, p. 563 ; Characium pyriforme A. Brattn, 1855, p. 40, Pi. 

 V. B. Cells obovoid with broadly rounded apex, base attenuate 

 into a capitate stipe, 9-13 /* long; total length of cell 18-25/1, 

 width 5-12 /*; chromatophores 1-4. Wis. Europe ', Africa. 



Var. SUBSESSIUS Lemmermann, 1914, p. 254, fig. il. C. 

 minuta P. B.-A., No. 1369. Smaller, cell 13-16 X 4-5 /" ; stipe 

 very short, 1.5-2 /A; chromatophore single. Cal. Europe. 



4. C. GROENI.ANDICA (P. Richter) Lemmermann, 1914, p. 

 255 ; Characium grocnlandicum P. Richter, 1897, p. 6. Cell 

 claviform or subfusiform, apex straight or more often slightly 

 curved, rounded, base gradually attenuate into non-capitate 

 stipe. Cells 50-150 X 7-25 /*, stipe about 12 /u. long ; chromato- 

 phore single ; zoospores numerous. On crustaceans. Greenland. 



5. C. CYLINDRICA (Lambert) Lemmermann, 1914, p. 256 ; 

 Characium cylindricum Lambert, 1909, p. 65, PI. LXXIX, figs, 

 i, 2, 7, 8, 10-13, 23-25; Collins, 1909, p. 151; P. B.-A., No. 

 1269. Cell cylindrical with rounded apex and tapering base, 

 24-430 X 10-20 p., stipe short, without basal disk ; chromato- 

 phores two; macrozoospores 8-16, escaping by a lateral open- 

 ing, microzoospores numerous, escaping by an apical opening. 

 Mass. 



6. C. ACUTA (A. Br.) Borzi, 1894, p. 153; Collins, 1909, 

 p. 99; Lemmermann, 1914, p. 257 ; Charadcum acutum A. Braun, 

 1855, p. 41, PI. V. C. ; Wolle, 1887, p. 177, PI. CLIX, fig. 2 ; 

 Wittr. & Nordst., No. 1236. Cell ovoid or broadly fusiform, 

 short-acuminate at each end, 20-38 X 6-10/1, stipe 3-4^ long, 

 with basal disk ; chromatophores 1-2 ; zoospores escaping by 

 apical opening. Pa. Europe. 



7. C. MINUTA (A. Br.) Borzi, 1894, p. 152 (as to name only) ; 

 Collins, 1909, p. 99 ; Lemmermann, 1914, p. 257, figs. 4-5 ; 

 Characium minutum A. Braun in Kiitzing, 1849, p. 892 ; 1855, 

 p. 46, PI. V. F. ; P. B.-A., No. 1221. Cell lanceolate, straight 

 or very slightly curved, ending in a short, curved apiculum, 

 base gradually attenuate into a short stipe with disk ; cells 

 12-38 X 3-8 p. ; chromatophore single; zoospores 4-8, escaping 

 by an apical opening. Mass., Cal. 



Europe, So. America, Australia, etc. 



Collins, 1900, fig. 6, does not represent this species, but C. 

 turgida W. & G. S. West, which has not yet been found in this 

 country. Borzi having first used the binominal Characiopsis 

 minuta, his name must be retained as author, although the 

 plant described and figured by him, 1894, p. 152, PI. XIV, figs. 



