CHLOROSPERME.E. 185 



Parasitical on the smaller AlgJE, generally on Ceramiiim ruhrum. — Fila- 

 ments 2 or 3 lines high, Ibrming elegant, pencilled tufts, much branched ; 

 branches straight or somewhat flexuous, erect or slightly spreading, close 

 or distant, the upper ones often closely set with minute, bud-like, 1- or 2- 

 jointed ramuli. Capsules minute, elliptical, solitary or clustered. I fear 

 the distinctions pointed out in Br. Fl. between C. Daviesii and virgatu- 

 lum cannot he depended on ; the latter appears to be merely a more ad- 

 vanced state of the former: nor can I discover any permanent characters 

 by which C. lanuginosum and C. secundatum, Ag. may be distinguished. 

 Cal. Daviesii bears a very close resemblance to Treniipohlia pulchclla, a 

 fresh-water Alga, inhabiting mountain streams. 



Sub-Class III. 



CHLOROSPERME.E or CONFERVALES. 



Harv. in Mack. Fl. Hib. part in. p. 220, (183G) ; Zoosper- 

 ME^, J. Ag. Alg. Medit. p. i. (1842). Nostochine.e, Ulvace^, 

 CoNFERVOiDE.^ {in part.) Ag. Syst. pp. xv. xxxii. Zoosper- 

 ME^ and Synspore^, Dne. Sc. Nat. xvii. p. 305. Confer- 

 VACE.ii and part of Phyce.e, Endl. PI. Sd Suppl. p. 10, 19. 

 Confervace.e and part o/"Fucace.e, Lindl. Veg. Kingd. pp. 

 14, 20. (DiATOME^, or Diatomace^, of authors, are also a 

 part of this sub-class). 



Diagnosis. — Plants greeu, rarely a livid purple. Fructi- 

 fication : dispersed through all parts of the frond, the whole 

 colouring matter being capable ot conversion into propagula ; 

 1, spores {Sporidia, Ag.), green or purple, formed within 

 the cells, often at maturity vivacious, moving by means of 

 vibratile cilia ; 2, coniocystce (Ag.), or external vesicles, 

 containing a dense, dark-coloured, granular mass, and finally 

 separating from the frond. Marine, or (more generally) 

 found in fresh-water streams, ponds, and ditches, or in 

 damp situations. (The marine species of this sub-class are 

 alone described in the present work). 



The plants of this sub-class are, in the vast majority of 

 cases, at once distinguished from all other Alga3 by the bright 



