Ser. MelanospermejE. Fam. Sporochno'ulea. 



Plate LXIV. 



ARTHROCLADIA VILLOSA, Duly. 



Gen. Char. Frond filiform, cellular, with an articulated, tubular axis, 

 nodose; the nodes producing whorls of delicate, jointed filaments. 

 Fructification ; pedicellate, moniliform pods, borne on the filaments, 

 and containing, at maturity, a string of elliptical spores. Arthrocladia 

 {Bub?/) — from apdpov, a joint, and kXHSos, a branch. 



Arthrocladia villosa. 



Arthrocladia villosa, Duly, Mem. Ceram. p. 18 (1832). /. Ag. Alg. Medit. 



p. 43. Midi. %rd Suppl. p. 25. Kiltz. Phyc. Gen. p. 344. 

 Elaionema villosum, Berk. Glean, p. 49. 1. 19. f. 3 (1833). Harv. Man. 



p. 28. 

 Sporochnus villosus, Ag. Sp. Alg. vol. i. p. 155. Ag. Syst. p. 260. Grev. 



Alg. Brit. p. 42. Hook. Br. PI. vol. ii. p. 274. Wyatt, Alg. Damn. no. 105. 



Harv. in Mack. PI. Hib. part 3. p. 173. 

 Conferva villosa, Huds. PI. Aug. p. 603. With. vol. iv. p. 141. E.Bot. 



t. 546. Dillw. Conf. t. 37. Roth. Cat. Bot. vol. hi. p. 314. 



Hab. On submarine rocks, shells, &c, and on Zostera, in four or five 

 fathoms water, rare. Annual. Summer and Autumn. Southern 

 coasts of England, not uncommon. Yarmouth, Turner. Anglesea, 

 Rev. H. Davies. Frith of Forth, Mr. Hasell. Ardthur, Copt. Car- 

 michael. Wicklow, W. H. PI. Malahide, and Carrickfergus, Mr. 

 McCalla. Jersey, Miss White aud Miss Turner. 



Geogr. Distr. Atlantic shores of Europe. Baltic sea. Mediterranean sea, 

 (very rare). 



Descr. Root, a minute disc. Fronds several from the same base, from six 

 inches to nearly three feet in length, very slender, once, twice, or thrice 

 pinnated ; the pinnae distant, opposite, or rarely alternate, patent, simple or 

 again pinnated with similar, simple pinnules ; all the branches furnished at 

 intervals of from half a line to a line, with minute, knob -like swellings which 

 produce whorls of very delicate, byssoid, repeatedly pinnate jointed fila- 

 ments of a pale green colour. The substance of the frond is traversed by a 

 wide tube, about one third of the width, which is divided by transverse sepia 

 into joints or chambers, whose length is rather less than their breadth, and 

 four or five of which interpose between every whorl of filaments. This 

 tube is surrounded by a row of large cellules, and these again by several 

 rows of smaller ones, which gradually diminish to the circumference. The 

 substance when quite fresh is cartilaginous, but it soon becomes flaccid. 

 Fructification ; minute, articulated, lanceolate pods (stichidia) borne along 

 the sides of the whorled filaments; at first short, finally much Lengthened, 

 moniliform, and containing, at maturity, in each joint, an ova] spore of an 

 olive colour, which at Length bursts through the membrane and falls away. 

 In drying it adheres firmly to paper. 



B 2 



