THE GREEN ALGAE OF NORTH AMERICA 419 



Var. TYPICA Weber, 1898, p. 352. Pedicel of varying height, 

 branches cylindrical or flattened, ramuli pinnate, subverticillate, 

 alternate, and imbricate, sometimes leaving a naked strip along 

 the back of the branch. 



Forma PASPALOIDES Weber, 1898, p. 352. Branches sub- 

 cylindrical ; ramuli pinnate ; pinnules with bases adjacent, 

 forked or with a single row of secondary pinnules. 



Forma PHLEOIDES (Bory) Weber, 1898, p. 353. Branches 

 subcylindrical, ramuli pinnate, pinnules with adjacent bases, 

 with tw y o rows of secondary pinnules. 



Forma COMPRESSA Weber, 1898, p. 353. Pedicel very short, 

 1-2 cm. long; branches 2-3 cm. long, cylindrical, digitate at 

 the summit of the pedicel, surrounded by very dense, imbricate 

 ramuli in many indistinct ranks; ramuli small, plane, with 

 simple or forking, opposite or subopposite, pinnately distichous, 

 patent pinnules. 



Forma FLABELLATA Weber, 1898, p. 353. Pedicel up to n 

 cm. high ; branches simple or branched, flabellately arranged 

 at the summit of the pedicel, flattened, ramuli distinctly in- 

 clined to right and left, with bases adjacent, dense, but not as 

 much so as in the preceding forms ; pinnules inclined to one 

 side, biseriate, simple or forked. 



Var. WURDEMANNI Weber, 1898, p. 353. Pedicel about 8 

 cm. high ; branches 10 cm. or more, with biseriate, subopposite 

 or scattered ramuli, bearing biseriate, simple, unilateral pin- 

 nules. 



Forma PHYLLOPHLASTON (Murray) Weber, 1898, p. 353 ; C. 

 phyllophlaston Murray, 1891, p. 207, PI. LIU, figs. 3-6. Pin- 

 nules uniseriate. 



Var LAXA Weber, 1898, p. 353. Pedicel up to 18 cm. high; 

 branches up to 28 cm.; arising fasciculately at the summit of 

 the pedicel, surrounded by very small, distant, subverticillate 

 ramuli ; pinnules small, simple, unilateral. 



Var. Wurdemanni forma phyllophlaston has so far been found 

 only in Yucatan ; the other varieties and forms at Florida and 

 the West Indies. 



14. C. RACEMOSA (Fb'rsk.) J. G. Agardh, 1872, p. 35 ; 

 Weber, 1898, p. 357, PI. XXXI, figs. 5-8; XXXII, figs. 1-7 ; 

 XXXIII ; P. B.-A., Nos. 767, 870; C. davifera Harvey, 1858, 

 p. 19; Alg. Am.-Bor., No. 39; P. B.-A., No. 270. Fronds 

 robust or delicate, simple or branched, ramuli distichous, alter- 

 nate, opposite, multiseriate, or imbricate. Ramuli with 

 rounded or plano-convex summit, enlarging insensibly from the 



