com BBV 171 



uncialis [Thi inch Cladophora) \ tofts very short, spongy, 

 simple below, above divided into numerous fastigiate, woolly 

 segments; filaments flexnous, sparingly branched, densely 

 interwoven; ramuli distant, seennd, Long, patent or incur 

 articulation- about twice as long as broad, Hun-. Fhtf. Brit, 

 pi. 207. (Aii.as. PL LX\ I 



igiomorpha uncialis, A'/:. Conferva uncialis, Fl. /J",/>. 

 < > 1 1 rocks, near low-water mark. Annual. May. 

 This plant more nearly resembles C. lanosa than any 

 other oi our native Bpecies, ami sometimes cannot be rea- 

 dily distinguished without a close examination; but it 

 forms much more dense and Bpongy tufts, which finally 

 ie more intricately interwoven together, and the 

 apices are seldom so distinctly fastigiate as in that species. 

 The habitat in which C. uncialis occurs affords an addi- 

 tional clue. It usually frequents rocky places, growi \ 

 the rock itself, or among the thin coating of sand which 

 •S it, in plaees close to the edge of low-water mark. 

 ■s,i. on the contrary, is almost always found as a 

 parasite on other Algae, or else attached to pieces of wood 

 and to the leaves of Zostera. To C. arcta our ('. uncialis 

 lias much resemblance, hut is a much smaller plant, with 

 very much more slender filaments. 



307. arcta {The straight Cladophora) ; filaments forming broad, 



-tarry tut'ts, of a brilliant green colour, much branched, and 

 mor matted together below; brandies straight, 



crowded, very erect: raiuuii appressed, opposite or alter- 

 nate, scattered; articulations in the older pails once ov 

 twice as long as broad, in the young (upper) branches many 

 times longer, A7:. Phyc. Ben. p. 263. (Atlas, PL 1A\ 1. 

 Fig. 310.) 

 Cladophora vaucherkeformis, Klz. ('. centralis, A'/:. Conferva 



arcta. Dillw. C. centralis, Lyngb. C. vaucheriaeformis. 

 l£ab. On exposed submarine rocks from half-tide level to low- 

 water mark. Perennial? Spring, Bummer, and autumn. 

 This species has a very different aspect at different pe- 

 growth, and it is not without a careful exami- 

 nation, and watching the plant as it progresses from its 

 infant state till It reaches maturity, ami gradually 



offinto old-age and decay, that it can he fully understood. 



1 believe that it always grows upon rocks, within the 



of the tide, hut nearly at the limit of low-H ater. and 

 in such places it frequently covers a considerable surface. 

 When young, ir is peculiarly vivid, and its aspect 



