CRYPTOGAMIA ALG.E. 255 



11. C.fracta, green, much branched and entangled; branches 

 scattered, divaricated ; joints twice as long as broad, cylindrical. 

 Eng. Bot. t. 2338. DILLW. Syn. 65. t. 14. HOOK. Scot. ii. 82. 



Hob. In stagnant pools not uncommon, floating in densely 

 entangled masses of a dull green colour. 



The older authors, under the name of Conferva bullosa, united 

 several species, which agreed in the common property of 

 retaining bubbles of air within the meshes of their entan 

 gled filaments. C. fracta is one of these which have been 

 used as wadding for stuffing garments, and wove into 

 coarse household linen. LIGHT FOOT says he has also seen 

 a coarse kind of paper made of it at Edinburgh. 



1 2. C. glomerata, green, very much branched ; branches alter- 

 nate, clustered, pencil-shaped, the ultimate ones directed to one 

 side ; joints cylindrical, five times as long as broad, their partitions 

 pellucid HOOK. Scot. ii. 82. GREV. Fl. Edin. 318. 



(a.) Fluviatilis, in running fresh water. C. glomerata, LIGHTF. 

 Scot. 993. DILLW. Syn. 65. t. 13. Eng. Bot. t. 2192. 



(b.) Littoralis, in pools of salt water. C. late-virens, DILLW. 

 S-yn. 66. t. 48. Eng. Bot. t. 1854. 



Hob. Rivulets, and the sea shore, abundant. 



The bed of little rapid rivulets is frequently rendered green 

 by the abundance of this species, which floats at the bot- 

 tom in very dense masses from 6 to 12 inches in length. 

 The sea variety, on this coast, rarely exceeds 3 inches, 

 and it is more rigid and less deeply coloured. In drying, 

 the plant scarcely adheres to paper. 



1 3. C. rupestris, densely tufted, deep green, much branched ; 

 branches erect, rigid, straight, rather obtuse ; joints 3 times as 

 long as broad or more, the partitions pellucid. LIGHTF. Scot. 994. 

 DILLW. Syn. 65. t. 23. Eng. Bot. t. 1699. HOOK. Scot. ii. 83. 



Hab. On rocks between low and high water marks, very 

 common. 



Tufts from 2 to 4 inches long. In drying it retains its fine 

 colour, and scarcely adheres to paper. 



159. ZYGNEMA. 

 1. Z. deciminum, green, soft, lubricous ; filaments long, with 



