171 SYNOPSIS OF BIUTISII SBAWEBD8. 



This species frequently fills the pools in which it grows, 

 and, rising in the water, covers the surface with a thick 

 fleece, under which large bubbles of air (a portion of which 

 is oxygen disengaged by tin* plant under the influence of 

 light) are confined. It is readily distinguished from C. 

 fracta by its paler green colour, as well as by the much 

 longer articulations, and their less granular contents. 



313. fracta (The broken Cfadophorctyi tufts irregular, entangled, 



often detached and then forming floating strata, dull— 

 filaments somewhat rigid, distantly branched, the I 

 branches somewhat diehotomous, spreading, with very wide 

 axils, the ramuli few, alternate or commonly Becund ; articu- 

 lations from three to six times as long as broad, at first cylin- 

 drical, then elliptical, with contracted dissepiments, Kiz. 

 Phyc. Gen. p. 2G3. (Atlas, PI. LXVII. Fig. 315.) 

 Conferva fracta, Fl. Ban. C. divaricata, Roth. C. vagabunda, 



Hnds. C. hirta, Fl. Ban. C. flavescens, Wyatt. 

 Hah. In ditches of brackish water, communicating with the tide; 

 also in fresh-water lakes, ditches, and streams. Common. 

 The occasional occurrence of this species in salt-water 

 ditches near the coast gives it a claim to be admitted into 

 the present work. C. front a is rarely found attached ; it 

 is more commonly met with heaped together in widely ex- 

 tending strata, covering the surface of the water. Some- 

 times in lakes, as it thus floats about, it becomes rolled 

 together in dense balls, which have a good deal of the 

 aspect of C. ceqayropila, but not the same regularly radiant 

 structure. When fully developed and in mature fruit, the 

 middle portion of the frond is very frequently entirely con- 

 verted into a string of sporangia, and is then a beautiful 

 and characteristic microscopic object, which it is impossible 

 to mistake for anything else. When not in fruit, C. fracta 

 is more easily known from C. flavescens by the shorter ar- 

 ticulations than by any other character. 



XCII. EHIZOCLONIUM. 



314. riparium {The shore Rhizocloniam); filaments Ion #, slender, 

 decumbent, pale-green, forming wide strafa, flaccid, en- 

 tangled, angularly bent, furnished at the angles with short, 

 root- like processes (which sometimes, but rarely, lengthen 

 into very patent branches, and often attach themselves to 

 neighbouring filaments), Harv. Thy. Brit.pl. 238. (Atlas, 

 PI. LXVII. Fig. 316.) 



