Ser. Melax'ospehmeje. Fam. Sporoc/moidea. 



Plate CXV. 



DESMARESTIA LIGULATA, Lamour. 



Gen. Char. Frond linear, either filiform, compressed or flat, distichously 

 branched, cellular, traversed by an internal, single-tubed jointed 

 filament ; producing, when young, marginal tufts of byssoid, branching 

 fibres. Fructification unknown. — Desmarestia (Lamour.), in honour 

 of A. G. JDesmarest, a celebrated French naturalist. 



Desmarestia ligulata; frond flat, with an obscure mid-rib, repeatedly 

 pinnate; pinnae and pinnulse opposite, linear-lanceolate, tapering 

 towards both extremities. 



Desmarestia ligulata, Lamour. Ess. p. 25. Grev. Alg. Brit. p. 37. t. 5. 

 Hook. Br. Fl. vol. ii. p. 273. Earv. in Mack. Fl. Hib. part 3. p. 172. Hare. 

 Man. p. 26. Wyatt, Alg. Damn, no. 55. Endl. 3rd Suppl. p. 28. Kiltz. 

 Phyc. Gen. p. 343. 



Desmia ligulata, Lyngb. Eyd. Dan. p. 33. t. 7. 



Sporochxus ligulatus, Ag. Sp. Alg. vol. i. p. 158. Ag. Syst. p. 261. Grer. 

 Fl. Edin. p. 287. Spreng. Syst. Veget. vol. iv. p. 330. 



Laminaria ligulata, Hook. Fl. Scot, part 2. p. 99. 



Fucus ligulatus, Light/. Fl. Scot. p. 946. t. 29. Turn. Syu. p. 99. Turn. 

 Hist. Fuc. t. 98. Sm. E. Dot. 1. 1636. 



Fucus lierbaceus, Hnds. Fl. Ang. p. 582. 



Hab. On the rocky bottoms of sub-marine tide-pools, near low water 

 mark; and at a greater depth. Annual. Summer. Not uncommon 

 on the shores of the British Islands from Orkney to Cornwall. Jersey. 



Geogr. Distr. European Atlantic, from the shores of the Fceroe Islands to the 

 coast of France. Cape Horn, Dr. Hooker. 



Descr. Root a large conical expansion, half an inch broad. Fronds from two 

 to six feet long or more, with a short, cylindrical, cartilaginous stem from 

 half a line to a line in diameter, which soon becomes compressed, and at 

 the distance of an inch or two from the base passes into the ilat, linear, 

 undivided frond, which gradually widens to its middle, and from thence is 

 attenuated to the apex: this primary frond is from one to four lines wide, 

 furnished with a more or less evident mid-rib, and closely pinnated, at 

 distances varying from an eighth of an inch to upwards of an inch, with 

 opposite, distichous branches. Branch* very variable in length, the long 

 and short ones mixed together without order; the -mailer ones simple, 

 from half an inch to an inch long, resembling lanceolate leaves; the larger 



pinnate or bipinnate, all the divisions being of a lanceolate form, hut varying 

 much in relative breadth in differenl specimens, sometimes not one third of 

 a line in breadth, sometimes three or four lines. All the pinnules are 



margined with minute spine-like teeth, which in young individuals produce 

 tufts of delicate, branching, jointed fibres, fructification unknown. Sub' 



f2 



