Laminaria.] ALGJ2 MELANOSPERME.E. 171 



ally midribbed, or variously costate. Fructification obscure ; " as 

 far as hitherto known, either seeds mixed with a mass of vertical, 

 jointed filaments or roundish granules, without Ji laments ; forming, 

 in both cases, dense-spreading spots or sori, on the surface of some 

 part of the frond," Grev. 



6. ALARIA. Grev. Alaria. 



Frond membranaceous, furnished with a percurrent, cartilagin- 

 ous midrib, the stem pinnated with distinct leaflets. Fruct. : 

 pyriform seeds, vertically arranged in the incrassated leaflets. 

 Grev. Name, ala, a wing, from the winged base of the 

 frond. 



1. A. esculenta, Grev. Esculent Alaria. Frond linear, en- 

 siform, entire at the margin; pinnae linear, oblong, fleshy." 

 Hook.Br. Fl. v. ii. p. 271. E. Bot. t. 1759. 



Northern and western shores, abundant. A beautiful plant as it 

 waves freely in the water. The frond is 3 10 or even 20 feet in 

 length, and 1 6 inches in breadth, consisting of a membranaceous, 

 very easily lacerated leaf, with a thick cartilaginous midrib. It is an 

 annual. 



7. LAMINARIA. Lamour. Laminaria. 



Frond coriaceous (rarely membranaceous), plane, expanded, 

 without a midrib. Fruct. : seeds or granules forming dense 

 sori or spots, and imbedded in the thickened surface of some 

 part of the frond. Grev. Name ; lamina, a thin plate. 



1. L. digitata, Lamour. Cleft Laminaria* Stipes coarse, 

 elongated, cylindrical, expanding into a broad roundish lamina, 

 which is deeply cleft into numerous linear segments. Hook. 

 Br. Fl. v. ii.p. 271. E. Bot. t. 2274. 



Sea-shores, in deep water. 2 12 feet long, olive brown. 



2. L. bulbosa, Lamour. Bulbous Laminaria. Root hollow, 

 swollen, tuberculated, bulb-like ; stipes flat, two-edged, twisted, 

 and deeply sinuated near the base, expanding into a broad ob- 

 long lamina, which is deeply cleft into numerous linear seg- 

 ments. Hook. Br. Fl. v. ii. p. 271. E. Bot. t. 1760. 



Sea-shores ; not uncommon on any of our coasts. 



3. L. saccharina, Lamour. Sugary Laminaria. Root 

 fibrous; stipes cylindrical, elongated, expanding into a cartila- 

 ginous, flat, oblong, entire frond. Hook. Br. Fl, v. ii. p. 272. 

 Turn. Hist. *. 163. 



Sea-shores, very common. 



4. L. Phyllitis, Lamour. Thin-leaved Laminaria. Root 

 fibrous ; stipes somewhat compressed, short, expanding into a 



