242 CRYPTOGAMIA ALG^E. 



Hob. On rocks, principally on sandstone, near high- water 

 mark, abundant in Berwick Bay ; also on a wall by the 

 river side at Tweedmouth church. 



" C. Rothii grows in patches of various sizes, generally, accord- 

 ing to Dr KOTH, affecting an oblong form. The colour is 

 a bright red, sometimes tending to brown, and changing, 

 when dried, to a beautiful shining crimson ; the filaments 

 are very slender, frequently not more than three lines, 

 and, I believe, never exceeding an inch in length ; they 

 .are erect, densely matted together, and much branched ; 

 the branches dichotomous, alternate, and most numerous 

 towards the apices ; the joints are cylindrical, and their 

 length is about equal to twice their thickness ; the inter- 

 stices pellucid." These remarks from DILLWYN agree 

 exactly with my own observations on this plant. It some- 

 times grows in places where it seems beyond the reach of 

 the sea, except in spring tides; and at our river side, 

 where it grows luxuriantly, it can only occasionally be 

 washed with brackish water. 



144. GEIFFITHSIA. 



1. G. setacea, bright crimson, tufted ; filaments capillary, branch- 

 ed; branches subdichotomous, erect-patent, long, straight, with 

 joints five times their diameter, GREV. FL Edin. 312. Conferva 

 setacea^ DILLW. Conf. p. 74, t. 82. 



Hab. Amongst sea refuse, in tufts about 1 or 2 inches in 

 height on this coast, not uncommon. 



The name of this genus is intended to commemorate Mrs 

 GRIFFITHS of Devonshire, a lady whose discoveries are 

 among the most important which have been made in ma- 

 rine botany. 



145. TRENTEPOHLIA. 



1. T. pulchella, reddish-brown, densely tufted ; filaments much 

 and irregularly branched ; branches erect, straight, tapered at the 

 ends, generally alternate, never opposite, with pellucid articu- 

 lations 4 times their diameter. LOUD. Encyclop. No. 15072. 

 Conferva nana, Eng. Bot. t. 2585. opt. 



Hab. On mosses in rapid streamlets. On Hypnum ripa- 

 rium, in the stream which runs through Lumsden Dean, 



