214 MONOCYSTE^E. 



pila, E. Bot. t. 1377. ; Dillw. Conf. t. 87. ; Harv. 1. c. 

 p. 357. ; also in Manual, p. 134. 



Hob. C. glomerata, common in streams and wells. C. 

 cegagropila, in lakes, rare. North Wales : Rev. M. 

 Dames. North of Scotland: Mr. Brodie. Prestwick 

 Car : Mr. Winch. Culmere Pool and Whitemore, 

 Shropshire : Rev. E. Williams. Cunnemara : Mr. Mac- 

 kay. C. Brownii. On wet rocks, in a cave near Dunree, 

 North of Ireland : R. Brown, Esq. On shady rocks at 

 the entrance of a small cave beyond Black Castle, 

 Wicklow, where it is exposed to the dripping of fresh 

 water, and occasional overflow of the sea: W. H. Harvey. 

 Cornwall coast, near the Land's End : Mr. Ralfs. 



This beautiful and abundant Conferva delights in pure and 

 running waters, attaching itself to stones, walls, and piles in 

 streams, rivers, and cascades, it being drawn out by the cur- 

 rent often to more than two feet in length. In the mass, it is of 

 a deep and refreshing green colour, which is occasioned by the 

 purity of the water in which it lives. Examined separately, 

 the filaments present a peculiar glistening appearance, rare 

 amongst freshwater Alga, though common to many marine 

 species. Not infrequently, the branches are beset with tufts 

 of ramuli, which, when the plant is floated out in water, give 

 it somewhat the appearance of a Sertularia, and increase 

 greatly its beauty. It is in this species that I have seen the 

 apertures situated on one side of the distal extremity of 

 the cells designed for the escape of the zoospores. Notwith- 

 standing that its usual resort is the stream and the waterfall, 

 it will flourish and increase in size amazingly for weeks and 

 months in a vessel, the water of which is occasionally re- 

 newed. I have thus kept it for many weeks, removing, when 

 by its growth it had filled the vessel, all but a small portion 

 of it ; this, however, speedily increased, and again filled its 

 dwelling-place. The tearing away of portions of the plant 

 in no way unpaired the vitality of the remainder, as from its 

 aggregation of minute cells, each the analogue of the other, 

 might a priori have been conjectured. 



