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 two 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 1 8 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 (Forsk.) 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. clavifcra 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 



