246 Marine Algae, of Berwick-on-Tweed. 



Class II.— C HLOEOPHYCEiE. 

 Order II.— CHLOKOZOOSPOKEiE. 



Family— U Ivacese. 



PEASIOLA (Ag.) Langerst. 



Prasiola stipitata, Suhr. 



Mscr. in Jessen Monogr. Prasiolse, p. 16. 



Descr. Prasiola stipitata, J. Ag., Till. Alg. Syst. vi., p. 86. 



Fig. „ „ Jessen, I.e. t. n., fig. 11-16. 



Syn. Prasiola marina, Crouan, Alg. Mar. Finist., no. 391 ; Id., Flor. du 



Finist. p. 130, pi. 9, den. 68. Holmes, Alg. Brit. Rar, no. 21. 



Prasiola stipitata, Langerstedt, Prasiol., p. 36. 

 Hub. On rocks near high-water mark. Jan. — Aug. Not uncommon. 



Berwick Bay, Sharper Head, rocks north of Uodd's Well. 



This pretty little species is to be met with plentifully during 

 the spring and early summer, but disappears later on in the year. 

 It forms indefinite patches, often of considerable extent on rocks 

 near high- water mark. The fronds are very small, usually about 

 a quarter of an inch long, and very seldom more than half an 

 inch. They are oval, oblong, or wedjje-shaped, tapering below 

 into a short stem, the margins usually more or less crisped. 

 Under the microscope the fronds have a tesselated appearance 

 rendering the plant unmistakable amongst British Marine Algse. 



M0N0STR0MA (Thur.) Wixtrock. 



Moxostroma Grevillei, Wittrock, 

 Monostr., p. 57. 

 Descr. Ulva lactuca, Harv., Phyc. Brit. 

 Fig. „ „ Harv., I.e. pi. 243. 



Syn. Monostroma Grevillei, J. Ag., Till. Alg. Syst. vi., p. 1U1 ; Hauck., 

 Meeresalg. p. 424. 

 Enteromorpha Grevillei, Thur., Note snr Syn. Ulv. p. 25. 

 Ulva Grevillei, Le Jol., Alg. Mar. Cherb., p. 37. 

 Ulva lactuca, Qrev. (non Linn), Alg. Brit., p. 172. 

 Harv., Phyc. Brit., pi. 243 ; Ktz., Spec. Alg., p. 474. 

 Id. Tab. Phyc. VI. t. 12; Johnston, Fl. Berwk. u., p. 25U. 



