1 75 



Ionium obtusangulum, Ktz. Conferva riparia, Roi 

 obtusangula, Lyngb. C. perreptans, 

 Wyatt. Zygnema littoreum, Lyngb. 

 Hah. On Band-covered rocks, near high-water mark. Annual. 

 Bummer. Noi common. 

 The specimens published by Mrs. Wyatt, under the 

 uame Conferva tortuosa, belong, in the copies "l" her valu- 

 able work which I have examined, to our R. riparium. I" 

 is more Blender than C. tortuosa, of a paler colour, and, 

 above all, distinguished by the root-like fibres which issue 

 at intervals from the articulations, and the presence of 

 which has induced Kiitzing to place it in a separate genus. 



315. Casparyi {Caspary*s Rhieoelonium) ; filaments elongated, 

 extremely Blender, decumbent, pale yellow-green, Btratified, 

 interwoven, curved, and here and there angularly bent 

 the angles emitting Bhorl root-like branches, which some- 

 times lengthen, and are filled with endochrome; arti 

 tions 2-6 times longer than broad, with narrow dissepiments 

 and granular endochrome, Harv. Pltijc. Brit. j>l. 35i, B. 



(Atlas, PL LXVIII. Pig. 318.) 



Hah. Falmouth and Penzance. 



This species has more slender filaments than the ordinary 

 22. riparium, and occasionally appears with Longer joints. 

 But the joints vary extremely in different threads, and 

 even in the same thread, so that I find it difficult to fix any 

 satisfactory character by which it can be known from It. 

 riparium, in the absence of specimens of that plant. 



XCni. CONFKRYA. 



31G. arenicola (The sand-inhabiting Conferva)*, w threads soft, 

 Bimple, extremely fine, matted, somewhat crisped, at first 

 uniform pale-green, at Length distinctly jointed ; articula- 

 tions once and half as long as broad, dotted; interstices 

 pellucid," Berk. Gl. Brit. Alg. p. 36. t. 13. / 8. (A 

 PL I.W II. Pig 317.) 

 Salt-marshes, within reach of the tide. 

 1 m indebted to Mr. Berkeley, from whose 'Gleanings' 

 I copy the above account, for a loan ^^ the original speci- 

 men from which his description was prepared. Except in 

 colour, this plant hears a close resemblance to ( . implexa. 



■U7. arenosa [Thi sandy Conferva)*, filament slender, straight- 

 ish, rigid, forming broad Btrata ; articulations from three to 

 five times Longer than broad, Carm. Alg. A \ 



PL LXVIII. Fig. 321.) 



