V. RHODOMELACE^. 43 



lations of the stem and branches areolatetl with small, irregular cells, more or less 

 obsolete ; of the raniuli once and a-half or twice as long as broad, marked with 

 numerous (secondary) tubes and small cells ; primary tubes four. Ag. Sp. Ah/, 

 vol. 2. p. 82. Kutz. Sp. Alg. p. 828. Harv. Phjc. Brit. t. 292 and 293. 



Hab. Boston Harbour in various places, rare ? Lynn Beach, Dr. Durkee. Ger- 

 man town, Miss E. H. Brewer, (v. v.) 



Root a large scutate disc. Fronds mostly solitary, 6-12 inches long, cartilaginous, 

 firm, as thick as packthread at the base, gradually attenuate upwards, decom- 

 poundly branched in a manner between dichotomous and alternate ; the branches 

 sometimes bare of ramuli, long and twiggy ; and sometimes emitting, especially 

 from their upper half, broad pencils of multifid, rosy or blood-red flaccid ramuli. 

 Internodes obscurely visible in all the older parts of the frond, distinctlj' marked 

 in the i-amuli alone, about once and half as long as broad, sometimes a little longer, 

 netted over with irregularly shaped, polygonal cells. A cross section shows four 

 primary tubes of a large size, protected externally by several rows of irregularly 

 placed cells, which are gradually smaller to the circumference. Conceptades ovate, 

 scattered over the branches. Tetrasjwres in the distorted tips of the flaccid ramuli. 

 Colour red-brown in the stem, rosy or blood-red in the ramuli. In drying, the stem 

 scarcely adheres to paper, except after strong pressure, but the ramuli, when pre- 

 sent, adhere very closely. 



A most variable plant in aspect. Specimens of the first year's growth have a 

 vei-y few flaccid ramuli scattered along the twiggy branches. In winter these, as 

 well as the ends of the branches, fall away, leaving a truncated or somewhat 

 pollarded frond. In the following spring, such as survive throw out a profusion of 

 byssoid and multifid ramuli, which are peculiarly abundant and dense round the 

 wounded pai'ts. 



16. PoLYSiPHONiA fibrillosa, Grev. ; pale straw-colour or brownish ; stems 

 inarticulate, opaque, marked with sinuous veins, robust, alternately branched ; 

 branches spreading, resembling the stem, but less opaque, articulated near the ends, 

 sub-simple, thickly set with very slender, articulated, finely divided, short ramuli, 

 whose tips are copiously fibrilliferous ; internodes of the ramuli. rather longer than 

 broad, bi-tri-striate ; primary tubes four, in the stem coated with a thick layer of 

 cells ; conceptades ovate ; tetraspores large, in the terminal ramuli. Ag. Sp. Alg. 

 vol. 2. p. "8. Kiitz. Sp p. 827- Harv. Bliyc. Brit. t. 302. 



Hab. Newport, Rhode Island, Prof. Bailey. Lynn, jNIassachussetts, and Peconic 

 Bay, Mr. Hooper, (v. v.) 



Tufted. Stems once or twice as thick as a hog's bristle, alternately much 

 branched, the lateral branches s])reading irregularly on all sides, re[)eatedly com- 

 pound ; the main stem and principal and lesser branches opaque and inarticulate, 



G 2 



