44 COLLINS AND HERVEY. 



8. Ramuli clustered. 10. C. fascicularis. 



8. Ramuli not clustered. 9. 



9. Ultimate ramuli very short, often of a single cell; cells in ramuli ovoid, 

 1-2 diam. long. 8. C. brachyclona. 



9. Ultimate ramuli not extremely short, cylindrical or nearly so. 



13. C. utriculosa. 



10. Cells generally with a sharp constriction near base. 



10. Cells without regular constrictions. 

 11. Fronds floating except at earhest stages. 

 11. Fronds always attached during active growth. 



12. Main filaments 30-60 n diam. 



12. Main filaments, 100-150 m diam. 

 13. Main filaments distinctly angled or flexuous. 

 13. Main filaments straight or nearly so. 



14. Pale yellow-green; cells 6-8 diam. long. 



14. Light to bright green; cells 2-6 diam. long. 

 15. Main filaments 60 n diam. or less. 

 15. Main filaments 80 /^ diam. or more. 



16. Some branches decumbent, attaching by rhizoids. 



16. No decumbent branches. 

 17. Color pale, glossy, substance soft. 

 17. Color darker, substance crisp. 



18. Cells 3-5 diam. long; ramuU scattered. 



18. Cells mostly 1-2 diam. long; ramuh closer and seriate. 



1. C. DELiCATULA Montagne, 1850, p. 302; Kiitzing, 1856, p. 1, 

 PL I, fig. 2; Collins, 1909, p. 337; P. B.-A., No. 2070. Ely's Harbor, 

 April, Hervey. Some of the plants were young and vigorous, reaching 

 a length of 10 cm. ; others were evidently old, the main branches with 

 laminate walls up to 15 ju thick, and covered with minute epiphytes; 

 new proliferous growth was very abundant, with delicate, thin walls, 

 and generally like the younger plants. 



2. C. LUTEOLA Harvey, 1858, p. 81; Collins, 1909, p. 338. Rein; 

 Merriman in Farlow herb. We have not collected this species, and 

 only these two records exist for Bermuda. 



3. C. CONSTRICTA CoIHns, 1909a, p. 19, PI. LXXVIII, figs. 4-5; 

 1909, p. 339. Hungry Bay, Feb., Hervey. Not over 3 cm. high, 

 while the original material from Jamaica reached a height of 10 cm. 

 The Bermuda plant occasionally sends out a very long, slender rhizoid 

 from one of the lower cells; this has not been seen in the Jamaica 

 material. 



4. C. CRLSPULA Vickers, 1905, p. 56; 1908, p. 19, PI. XVI; Collins, 



