Ser. MELANOSPERMEJ:. Fam. FUCACEiE. 



Plate CXXX. 

 HALIDEYS SILIQ-UOSA^—Lpigb. 



Gen. Chak. — Frond coriaceous, linear, two-edged, distichously branclied ; air-vessels 

 stalked, linear oblong, divided by numerous transverse dissepiments, and traversed 

 by longitudinal filaments. Fructification : oblong stalked receptacles, containing 

 immersed spherical conceptacles, communicating with the surface by a minute pore, 

 and containing attached to their walls oblong spores, mixed with antheridia. 

 Name from &\s, "the sea," and Spvs, " an oak." 



Halidbts siliquosa. — Fronds alternately bipinnate or tripinnate ; 

 pinnules very short, obtuse ; vesicles mucronate, often terminated by a 

 receptacle. 



Hajidrts siliquosa. — Lyngh. Hyd. Dan. p. 37; Orev. Alg. Brit. p. 9, t. 1; Hoolc. 

 Br. Fl. vol. U. p. 266 ; Wyatt, Alg. Damn. No. 53 ; Endl. 3rd Suppl. 

 p. 30; Harv. in Maclc. Fl. Hib. part 3, p. 168 ; Harv. P.B. plate 6Q\ 

 Harv. Man. p. 15; Harv. Syn. p. 12; Atlas, plate 1, fig. 3; Harv. N. 

 B. A. part 1, p. 64 ; /. Q. Agardh, Sp. Gen. Alg. vol. i. p. 236. 



Cystoseira siliquosa. — Ag. Sp. Alg. vol. i. p. 72; Ag. Syst. p. 287; Spreng. Syst. 

 Veg. vol. iv. p. 317 ; Grev. Fl. Edin. p. 285. 



Fucus siliquosus. — Liim. 5p. PI. p. 1829 ; Syst. Nat. vol. ii. p. 716 ; Fl. Lapp. 

 p. 365; Gm. Hist. p. 81, t. 2b; Fl. Ban. t. 106; Huds. Fl. Angl. 

 p. 574 ; Lightf. Fl. Scot. vol. ii. p. 921 ; With. Ar. Brit. PL vol. iv. 

 p. 88 ; Good. & Woodw. in Linn. Trans, vol. iii. p. 124 ; E. Bot. 

 t. 474 ; Staclc. Ner. Brit. p. 8, t. 5 ; Turn. Syn. vol. i. p. 60 ; Hist. 

 t. 159 ; Esper, Ic. Fuc. t. 8. 



Fucus siliculosus. — StacJc. Ner. Brit. t. 11. 



Hab. — On rocks and stones in the sea to half- tide level. Perennial. Spring and winter. 

 Very common on all our shores. 



Geogr. Dist. — North Sea ; Northern Atlantic, 



Description. — Root, a large spreading conical disc, very hard and 

 woody. Fronds two feet or more in length, more or less cylindrical at 

 the base, and often half an inch in diameter, becoming nan'ower, com- 

 pressed, and two-edged upwards, and from one to two lines in breadth, 

 bi-tripinnate. Branches alternate, erecto-patent, two-edged, often changed 

 iiito vesicles; these are large and conspicuous, linear oblong, mucro- 

 nate, with thick walls, the cavity divided by numerous diaphragms, and 

 traversed by several longitudinal filaments ; lower pinnae rather distant, 

 often interrupted, or their place occupied by a vesicle ; pinnules closer, 

 more regular, and generally terminating in a pinnated raceme of vesicles 

 VOL. in. B 



