44 COLLINS AND HEEVET. 



8. Ramuli Clustered. 10- C. fascicularis. 



8. Ramuli not clustered. 

 9. intimate 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. 3. C. constricta. 



10. CeUs without regular constrictions. ll- 



11. Fronds floating except at earliest stages. 12. 



11. Fronds always attached during active growth. 13. 



12. Main filaments 30-60 ^ diam. 4. C. crispula. 



12. Main filaments, 100-150 ^ diam. 7. C. expansa. 



13. Main filaments distinctly angled or fiexuous. 14. 



13. Main filaments straight or nearly so. 15. 



14. Pale yellow-green; cells 6-8 diam. long. 2. C. luteola. 



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



15. Main filaments 60 ii diam. or less. 1. C. deUcatula. 



15. Main filaments 80 m diam. or more. 16. 



16. Some branches decumbent, attaching by rhizoids. 5. C. coraUicola. 



16. Xo decmnbent branches. 17. 



17. Color pale, glossy, substance soft. 9. C. crystaUina. 



17. Color darker, substance crisp. 18. 



18. Cells 3-5 diam. long; ramuli scattered. 11. C. piscinae. 



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



12. C. rigidula. 



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

 PI. 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 /tt thick, and covered with minute epiphytes; 

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

 and generally Hke the younger plants. 



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

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

 only these two records exist for Bermuda. 



3. C. coxsTRiCTA CoUins, 1909a, p. 19, PL LXXATCH, figs. 4-5; 

 1909, p. 339. Hungry Bay, Peb., 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. CRISPULA Vickers, 1905, p. 56; 1908, p. 19, PI. XVI; Collins, 



