THE GREEN ALGAE OF NORTH AMERICA 403 



6. Ratnuli forming a distichous plumule. 7. 



6. Ramuli forming an apparently secund plumule. 8. 



7. Plumule linear to linear-lanceolate; stems seldom branched. 



7. B.pennata. 

 7. Plumule usually triangular ; stems generally freely branched. 



3. B. plumosa. 

 8. Ramuli forming a plumule over all but the base of the rachis. 



9. B. foliosa. 

 8. Ramuli in a short series below the naked, often incurved tip. 



8. B. Harveyana. 



1. B. HYPNOIDES L,amouroux, 1809, p. 135, PI. I, fig. 2, a 

 and b ; Harvey, 1846-51, PI. CXIX ; Vickers, 1908, p. 30, PI. 

 LJII ; P. B.-A., Nos. 1028, 1286; not474- Frond seldom over 

 10 cm. high, soft, rather pale green, usually much branched, 

 branches in no definite order, growing smaller in the successive 

 series, and with no sharp division between the lesser branches 

 and the ramuli that clothe them on all sides, and themselves 

 branch more or less. Southern Mass, to W. I. ; Washington to 

 southern Cal. Europe. 



A common European species, considered rare on our Atlantic 

 coast, but probably often mistaken for B. plunwsa. There is 

 little distinction between the various orders of branches, and 

 though the plant is delicate and graceful, there are none of the 

 definite plumules characteristic of B. plunwsa and its allies. 



2. B. DUCHASSAINGII J. G. Agardh, 1854, p. 107; 1886, p. 

 31 ; B. hypnoidcs P. B.-A., No. 474, not 1028, 1286 ; Trichosolen 

 antillariim Montague, 1860, p. 171, PI. XI. C. Frond up to 20 

 cm. high, rather pale green ; stem stout, main branches long, 

 virgate, with one or more series of similar branches, covered in 

 the upper part with a woolly coating of short ramuli, shorter 

 towards the end of the branch, giving the branch a linear or 

 linear-lanceolate outline with acute tip ; also with numerous 

 short, slender, secondary branches, bare below, the upper part 

 densely covered with minute ramuli. Fla., W. I. 



The main stems are stouter than in B. hypnoidcs, the ramuli 

 are shorter and denser, the branches virgate and not much 

 divided. The branches vary much in length, and the frond 

 does not have the regular outline usually found in most species 

 of Bryopsis. 



3. B. PLUMOSA (Huds.) Agardh, 1822, p. 448; Harvey 

 1846-51, PI. Ill; 1858, p. 31 ; Farlow, 1881, p. 59, PI. IV, fig. 

 i ; P. B.-A., No. 227. Frond seldom over 10 cm. high, rich 

 and glossy green ; amount of branching variable ; typical forms 



