Ser. GOXGYLOSrERMEiE. ( 75 ) Fam. CRYrTONEMTACEJi:. 



Plate XCV. 

 SCHIZYMENIA DUBYI.— /. G. Ag. 



Gen. Char. — Frond subcarnose-memljranaceous, flat, composed of two strata : the inner 

 of longitudinal, anastomosing and interlacing, articulated filaments ; the outer 

 of cells, of which the inner are large, ovate, irregular, the oiiter smaller, and 

 disposed in moniliform vertical series. Fructification of two kinds, on distinct 

 plants : 1. Favellidia, more or less immersed in the substance of the frond ; 

 2. Tetraspores, tripartite or cruciate, scattered ' among the filaments of the 

 periphery. Name from o-x'C'*', " I divide, " and ii/xV, " a membrane." 



ScHiZTMENiA Duhyi. — Froud submembranaceous, thin, flat, obovate 

 or oblong ovate, sometimes divided to the base into linear, oblong or 

 obovate lacinise or segments. 



ScnizTMENiA Duhyi. — /. G. Agardh, Sp. Gen. Alg. vol. ii. p. 171. 



Kallymenia Duhyi. — Harv. P. B. plate 123 ; Harv. Man. p. 150; Harv. Syn. 

 p. 123 ; Atlas, plate 47, fig. 214. 



Haltmenia Duhyi. — Chauv. Bot. Gall, p, 944. 



Haltmenia laminarioides. — Bory, sec. Lenorni. 



Nemostoma Duhyi. — /. Ag. Alg. Medit. in not. p. 96. 



Irid^a Duhyi. — Lenorm. in Herh. 



Delesseria Ferrarii. — Bonnem. et Lamour. sec. Lenorm. 



Hab. — On rocks, stones, &c., within tide-marks. Annual. Spring and early summer. 

 Falmouth Harbour (3Iiss Warren) ; Plymouth (Rev. W. S. Hore, J. W. Rohloff) ; 

 Carnlough Bay, 1833 {Miss Davison) ; Belfast Bay in ten fathoms (TF. Thompson); 

 Glenarm, co. Antrim, Ireland (D. Moore). 



Geogr. Dist. — Atlantic coasts of France and Spain. 



Description. — Root, a small flat disc. Stem veiy short, scarcely a 

 quarter of an inch long, cylindrical at the base, but immediately expand- 

 ing into the base of the frond, whose normal fonn is obovate, entire, six 

 inches to a foot in length, somewhat tufted, the margin quite entire, but 

 more or less full and undulating, broad and rounded at the summit, 

 but gradually tapering to the base : frequently, however, the frond is 

 cleft nearly to the base, the divisions assuming the normal form, or are 

 more or less oblong, entire, or again cut or cleft more or less deeply ; 

 sometimes the fi-ond is entire, oblong, or roundish oblong, and nearly as 

 wide in the lower as in the upper half. Structure consisting of an axis, 

 occupying one-half the diameter, and composed of slender articulated 



