234 ALG^E CHLOROSPERMEiE. [Rivularia. 



Pools and ditches. About Limerick, &c. 



2. V. velutina, Ag. Velvet Vaucheria. Filaments creeping; 

 branches erect, fastigiate, woven into a velvetty stratum ; cap- 

 sules solitary, lateral. Carm. — Hook. Br. Fl. v. ii. p. 319. 



On the muddy sea-shore. At Miltown Malbay. 



3. V. Dillwynii, Ag. Dillwyns Vaucheria. Fronds 

 branched, flexuose ; vesicles globose, lateral, sessile. Hook. Br. 

 Fl. v. ii. p. 320. — Conffrigida, Dillw. t. 16. 



On the ground, in damp places, common. 



4. V. terrestris, D C. Ground Vaucheria. Filaments 

 straight, forming a lax, somewhat bristly stratum (upon the 

 ground) ; vesicles lateral, hemisphaerical on the side of the horn- 

 shaped peduncle or receptacle. Grev. — Hook. Br. Fl. v. ii. 

 p. 320. 



On the ground, in moist shady places. 



* H< Vesicles tioo or more together. 



5. V. ccespitosa, Ag. Tufted Vaucheria. Filaments caaspi- 

 tose ; branches secund, fructiferous at the apex; vesicles ses- 

 sile, globose, intermediate horn-shaped, process straight or 

 curved. Carm. Hook. Br. Fl. v. ii. p. 321. — Conf. amphibia, 

 Dillw. t. 41. 



On damp earth, or by the side of ditches, &c. 



Tribe XIX. OSCILLATORIE^. 



Plants growing in the sea, in fresh water, or on damp ground, 

 of a gelatinous substance and filamentous structure. Filaments 

 slender, tubular, continuous, filled with a coloured, granular, trans- 

 versely striate matter, seldom branched, though often agglutinated 

 together so as to appear branched, usually massed together in broad, 

 floating, vr sessile strata of a very gelatinous nature ; occasionally 

 erect and tufted, and still more rarely collected into radiating series, 

 bound together by firm gelatine, and then forming globose, lobed, or 

 plane-cr ustaceous fronds. Fructification. : an internal mass, di- 

 vided by transverse septa, finally separating itito roundish or lenti- 

 cular sporidia. 



70. Rivularia. Roth. Rivularia. 



Frond globose or lobed, rarely incrusting, green or olivaceous, 

 carnose or gelatinous, composed of continuous filaments, an- 

 nulated within, and surrounded by, or set in, gelatine.-— 

 Name, in allusion to the habitat of some of the species. 



