ptca( 15 



time no part of England lias been more zealously or more 

 successfully explored, by a multitude of skilful observers, 

 than the coasts of Devonshire and Cornwall, bu1 no one 



has met with a sera]) <>f this plant ; wherefore 1 fear it is 

 but too evident thai it lias no claim to a place in our 



list. 



7. foeniculacea The Fennel-leaved Cysto8eira)\ stem com] 



branches Long, slender, rough with hard point-, repeatedly 

 dichotomo-pinnate j air-vessels small, solitary or two to- 

 gether, elliptical oblong, placed near the tip- of the branches : 



receptacles minute, smooth, linear-lanceolate, Grev. Alg. Br, 



p. (5. (Atlas, PL II. Fig. 7.) 



ira discors, Ag. C. abrotanifolia, Ag. Fucus fceniculaceus, 

 Linn. V. discors, Linn. V. abrotanifolius, Linn. 



Hah. Atlantic shores of England. Growing on rocks, in tide* 

 pools, near low-water mark. Perennial. Summer. 

 I follow Turner, and all succeeding British writers, in 

 uniting, under the common name foeniculacea, the Fucus 

 discors and F. abrotanifolius of Linnaeus, which Conti- 

 nental authorities, without exception, retain in the rank 

 of species. Mrs. (Jritliths, on the accuracy of who 

 serrations made 1 during many years' familiarity with this 

 species I place implicit reliance, states that Buch specimens 

 as grow in deep water, where they are seldom or never 

 exposed by the tides, constitute the F. discors «>f authors, 

 especially if collected in summer, at which season th< 

 extremely luxuriant, with broad leaves and large air-blad- 

 ders : and that fronds which are developed in shallow tide- 

 pools, or collected late in autumn or winter, being more 

 branched, and having narrower leaves, make the /*'. abro- 

 tanifolius. ( >n the depth o^ water, or difference of s< 

 therefore, depend all the characters on which it has been 

 attempted to erect two species. 



8. fibrosa (77/ e fibrous Oystoseyrd) \ stem woody, compr 



vt -r\ much branched ; branches slender, alternately bi-'tri- 

 pinnate; pinnules furnished with linear, setaceous, acut< 

 ramuli ; vesicles elliptical, solitary or in pairs, immersed in 

 1 1 k* Bmaller branches, remote from the apices ; receptacles 

 linear, very Long, more or Less clothed with setaceous ramuli, 

 Ag. Sp. Alg. v. L. p. 65. (Atlas, PL 11. Fig. 6.) 



Phyllacantha fibrosa, Kiitz. Fucus fibrosus, Ihuls. F. abrotano- 

 idee, Ghnel. V. baccatus, G F. setaceus, Hud. 



Hob. Frequent on the Bhoresof England and of the north, west, 



