tier. MelanosfermEjE. lam. Fucete. 



Plate CXXXI1I. 



CYSTOSEIRA FIBROSA, Ag, 



Gen. Char. Frond much branched, occasionally leafy at the base ; branches 

 becoming more slender upwards, and containing strings of simple 

 air-vessels within their substance. Receptacles terminal, small, cellu- 

 lar, pierced by numerous pores, which communicate with immersed, 

 spherical concejjtaclcs, containing parietal spores, and tufted anther id la. 

 Cystoseira (Ag.), — from kvo-tls, a bladder and aetpa, a chain; because 

 the air-vessels are often arranged in strings. 



Cystoseira fibrosa; stem woody, compressed, very much branched; 

 branches slender, alternately bi-tri-pinnate, pinnules furnished with 

 linear, setaceous, acute ramuli ; vesicles elliptical, solitary or in pairs, 

 immersed in the smaller branches, remote from the apices ; receptacles 

 linear, very long, more or less clothed with setaceous ramuli. 



Cystoseira fibrosa, Ag. Sp. Ahj. vol. i. p. 65. Ag. Syst. p. 285. Spreng. 

 Syst. Veg. vol. iv. p. 317. Grev. Alg. Brit. p. 8. Hook. Br. Fl. vol. ii. 

 p. 266. Harv. in Mack. Fl. Hid. part 3. p. 168. Harv. Man. p. 19. Wyatt, 

 Alg. Damn. no. 52. Endl. 3rd Suppl. p. 30. Fl. Ban. t. 1902. 



Phyllacantha fibrosa, Kiitz. Fhyc. Gen. p. 356. 



IVcus fibrosus, Huds. Fl. Aug. p. 575. Good, and Woodio. in Linn. Trans. 

 vol. hi. p. 137. With. vol. iv. p. 87. Stack. Ner. Brit. p. 80. t. 14. Tnm. 

 Syn. vol. i. p. 93. Turn. Hist. t. 209. E. Bot. t. 1969. Lamour. Ens. p. 18. 



Fccus abrotanoides, Gmel. p. 89. Esper, p. 65. t. 29. 



Fucus baccatus, Gmel. p. 90. t. 3. f. 2. Esper, Ic. p. 108. t, 54. 



Fucus setaceus, Huds. Fl. Aug. p. 575- 



11a B. On rocks, near low-water mark and in tide-pools; also in 4-15 

 fathom water. Perennial. Summer. Frequent on the shores of 

 England and of the north, west, and south of Ireland. Not found in 

 Scotland. 



Geogr. Distr. Atlantic shores of Europe, from England to Spain. 



Descr. Root a large, hard, conical expansion. Fronds mostly solitary, from 

 two to three feet long, or more, very bushy, and excessively branched. 

 Main stem as thick as a swan's quill, simple, or once or twice branched, 

 from six inches to afoot in length, furnished throughout with alternate, 

 subdistichous slender branches, accompanied b) more or less numerous, 

 linear, simple or forked, narrow Leaves, which are furnished with a mid-rib 

 and attenuated to each extremity. Branches from one to two feel in 

 length, as thick as small twine. SOmewhal compressed, gradually attenuated 

 from the base to the apex, Imt without any swelling at the hase, more or 

 less naked below, and rough witli the remains of broken ramuli, eloseK 



(initiated above with alternate, distichous branchlets, which in like manner 

 are pinnated with a second, and these with a third series of branchlets, 



