Seii. GONGYLOSrEU]\IE.E. ( 55 ) Fam. CKYPTONEMIACEiE. 



Plate LXXXVIIL 

 GIGARTINA VIST11.1.AT A.— La mour. 



Gen. Char. — Frond cartilaginous, filiform, compressed or flat, consisting of two strata; 

 inner of lougitudiual, interlacing and anastomosing filaments ; the outer of 

 vertical, dichotomous, articulated filaments, loosely imbedded in a firm jelly, the 

 apical joints of wliicli are minute, moniliform, coloui'ed, not branching, parallel, 

 and firmly cohering. Fructification of two kinds, on distinct plants : 1. "External 

 tubercles, containing on a central placenta dense clusters of spores (favellidia), 

 held together by a network of fibres" {Harv.) ; 2. Tetraspores, "scattered among 

 the filaments of the periphery," or collected into immersed sori. 



GiGARTiXA jyistiUata. — Frond compressed, stalked, somewhat dichoto- 

 mously branched in a sub-flabelliform manner ; branches very patent, 

 naked or pinnated with short patent ramuli ; tubercles solitary or in 

 pairs ; tetrasj^ores in sori in the ramuli. 



GiGi.K]:isA. pistillata. — Lamour. Ess. p. 49; Grev. Alg. Brit. p. 146; Hooh. Br. Fl. 

 vol. ii. p. 300 ; Endl. Srd Suppl. p. 41 ; Kiltz. Phyc. Gen. p. 402, 

 t. 70, f. 1 ; Mont. Fl. Alg. p. 99; /. G. Agardh, Sp. Gen. Alg. 

 vol. ii. p. 264 ; Harv. P. B. plate 232 ; Harv. Man. p. 140 ; Harv. 

 Syn. p. 113 ; Atlas, plate 43, fig. 197. 



SpHiEROCOccus gigartinus. — Ag. Sp. Alg. vol. i. p. 274 ; Ag. Syst. p. 224. 



Fucus pistillatus. — Gmel. Fuc. p. 159, t. 12, f. 1 ; Lam. Diss. p. 51, t. 27. 



Vxicvs gigartinus. — Linn. Syst. Nat. vol. ii. p. 719; Good. & Woodio. in Linn. 

 Trans, vol. iii. p. 183, t. 17, figs. 3, 4 ; ^. Bot. t. 908; With. vol. iv. 

 p. Ill ; Turn. Syn. vol. ii. p. 280 ; Turn. Hist. t. 28. 



Fucus CEderi. — Esper, t. 135. 



Ceramium gigartinum. — Roth, Cat. vol. iii. p. 109. 



Hab. — On rocks near low-water mark. Perennial. Winter. Very rare. Coast of 

 Cpmwall, in several places (Hon. Dr. Wenman, before 1800); St. Ives (Stackhouse) ; 

 Penzance (Brodie) ; Padstow {Miss Hill) ; Mouth of the Padstow River on rocks {Airs. 

 Griffiths) ; Mounts Bay (Dr. McCulloch) ; Whitsand Bay (Dr. Jacob, 1829, Gilbert 

 Saunders, 1848) ; Jersey (Miss Turner). 



Geogr. Dist. — Atlantic shores of France and Spain ; Mediterranean Sea. 



Description. — Root, a flat disc. Fronds much tufted, two to five 

 inches high. Stem about one-half the length of the frond, cylindrical or 

 nearly so at the base, but gradually becoming more compressed upwards 

 to the forking, where it generally reaches its greatest compression, the 

 branches becoming gradually rounder upwards, the ultimate ramuli being 

 again nearly cylindrical. Fronds three to five times dichotomous ; 



