Ser. Mela>!OsperjiejE. Fam. Chordariea. 



Plate LXXXII. 



MESOGLOIA VIRESCENS, Carm. 



Gen. Char. Frond filiform, much branched, gelatinous. Axis composed 

 of loosely packed, longitudinal, interlaced filaments, invested with 

 gelatine ; the periphery of radiating, dichotomous filaments whose 

 apices produce clusters of club-shaped, moniliform fibres. Fructifica- 

 tion, obovate spores, seated among the apical fibres. Mesogloia 

 (Ag.) from /xeVoy, the middle-, and yXotos, viscid; in allusion to the 

 gelatinous axis. 



Mosogloia virescens ; frond filiform, gelatinous ; branches long, slender, 

 villous ; ramuli numerous, patent, short, linear, obtuse. 



Mesogloia virescens, Carm. Alg. Appin. ined. Hook. Br. Fl. vol. ii. p. 387. 

 Wyatt, Alg. Damn. no. 49. Berk. Gl. Alg. t. 17. f. 2. 



Mesogloia affinis, Berk. Gl. Alg. 1. 16. f. 2. 



Mesogloia Hornemanni, Suhr. ? Kiitz. Phyc, Gen. p. 332 ? 



Tricholadia virescens, Harv. in Mack. Fl. Hib. part 3. p. 184. 



Helminthocladia virescens, Harv. Man. p46. 



iS, Zoster icola ; frond brownish, simple, with a few short branches. 



Mesogloia gracilis, Carm. Alg. Appin. ined. Berk. Gl. Alg. t. 17. f. 1. 

 Endl. 3rd Suppl. p. 23. 



Mesogloia Zosterae, Aresch. 



Rivularia Zosterse, Mohr. in Weber. Beitr. vol. ii. p. 367. Lyngb. Hyd. 

 Ban. p. 194. t. 66. 



Hab. On rocks, stones, and Algae, at half-tide level. Annual. Spring 

 and Summer. Common. West of Scotland, Carmichael, Rev. 1). 

 Landsborov.gh, 8fc. North of Ireland, Mr. IF. Thompson. West, 

 south, and east of Ireland, abundant. South coast of England, Mrs. 

 Griffiths, Sfc. 0, parasitical on Zostera, at Appin, Capt. Carmichael. 

 ftoundstone Bay, Mr. Mc'Calla. 



Geogr. Distr. Northern shores of Europe. Baltic Sea. Atlantic coasts of 

 France. 



Descr. Root scutate. Frond from four to twelve or fourteen inches in length, and 

 from half to nearly a hue in diameter, cylindrical, filiform, equal in diameter 

 throughout its extent, with an undivided stem, densely clothed with lateral 

 brandies. Branches issuing at short distances from each other, sometimes 

 as long as the stem, sometimes half as long, and in \ar. /3. very short, 

 patent, resembling the main stem, and like: it having numerous, lateral, 

 simple or forked, patent secondary branches. Every part of the frond 

 appearing villous to the naked eve from the greai Length, and little density 

 of the stratum of filaments, which form the periphery. These JUament* arc 

 irregularly dichotomous or somewhat fascicled; their divisions moniliform, 



