V. RHODOMELACE.E. 57 



Hab. On mangrove stems, and on logs about the wharf, at Key West, W. II. H. 

 (No. 7). Pine Island, Prof. Tuomey (10^) (v. v.) 



Stems 1-2 inches high, as thick as hog's bristle, alternately branched ; branches 

 an inch long, horizontally patent, simple or once or twice divided, distichous, closely 

 bi-tri-pinnate. The lower parts of the stem are generally beset with short, spine-like, 

 broken branches, the remains of earlier growth ; the upper parts, as well as the 

 main branches and their divisions, closely beset with very slender, alternate, patent, 

 simple or multitid, infiexed or involute, capillary ramuli. The stems and branches 

 and the primary pinnae are solid, inarticulate, and clotted with quadrate cells ; tlie 

 pinnulaj and their divisions articulate, formed of a single series of oblong cells, 

 once and half or twice as lonsr as broad. A cross section of the stem shows a small 

 central cavity surrounded by numerous rows of coloured cells. Conceptades ovate, 

 terminating the primary pinnte, containing a tuft of pear-shaped spores. Stichidia 

 spindle shaped, terminal, curved, acuminate. Colour a brownish purple. Substance 

 cartilaginous, rigid. It does not adhere to paper. 



Our specimens agree with those received by Dr. Montague from Cuba. They 

 differ from the plant described in Harv. Ner. Austr. as above quoted, in being erect, 

 and destitute of root-like discs. 



Plate XIV. C. Fig. 1. Bostbtchia calamistrata, the natural size. Fig. 2, apex 

 of a branch, with conceptades ; Jig. 3, a conceptacle and ramulus ; Jig. 4, spores ; 

 Jig. 5, small portions of the ramulus ; Jig. 6, cross section of the stem ; jig. 7, a 

 stichidium ; all more or less highly magnijied. 



Sub-genus 2. Stictosiphonia. Peripheric cells in a single row 



3. BosTRYCHiA rimdaris; stems an inch high, rising from creeping filaments, 

 capillary, bipinnate; pinna? distichous, alternate, patent, inarticulate, tessellated 

 with subquadrate cells ; pinnulaj subdistant, simple or forked, attenuate, marked 

 with about two rows of oblong cells ; peripheric cells seven or eight ; conceptades 

 ovate, terminating the lowest pinnae, which are then abbreviated and bare of pin- 

 nules. (Tab. XIV. D.) 



Hab. Isle of Shoals, Mr. Pike. Hellgate, New York, Mr. Hooper. On Spartina 

 glabra, and on the Palmetto logs in the Ashley and Cooper Rivers, Charleston, 

 Prof. Bailey and W. H. H., also found by Prof Bailey in the St. John's River, 

 Florida, (v. v.) 



Fronds an inch high or less, slender, spreading over the logs in wide patches, 

 rising from a mat of creeping fibres, attached here and there by discs. Stems some- 

 what flexuous, erect, pinnate or bipinnate, or in luxuriant specimens sub-tripinnate. 

 P/n?ia' altei-nate, distant, spreading, laxly pinnuhite. PinnuUv also patent, subulate, 

 sometimes again compounded. The whole frond is tessellated with quadrate or oblong 

 cells arranged in longitudinal rows, the ramuli having about two rows, the larger 



VOL. IV. — ART. 5. I 



