120 CHiETOPIIORE^. 



bands across the cells, and essentially in its reproduction. The 

 only real difference between the genera consists in the filaments 

 of the one being simple and those of the other branched. In 

 an arrangement, therefore, in wliich affinities are studied, 

 these two genera should be placed near to each other. 



1. DrAPARNALDIA GL03IERATA Aff. 



PI. XIII. Fig. 1. 



Cha?'. Stem rou7id, branched. Ramuli in tuffs, ivltich are 



frequently alternate a?id ahoays ciliated. Tufts divergent. 



Hah. Everywhere common in slow streams and ditches, 



adhering to stones, sticks, &:c. 

 Draparnaldia (jnutahilis) gelatinosa ; filamentis crassiusculis ; 

 ramis suhjnnnatis, ohtusiuscidis ; fasciculis hreviusculis, 

 comjjlicatis, Bory, in Annales du Museum, pi. 35. fig. 1 . 

 Conferva mutahilis Roth, Cat. Bot. i. 197. Flor. Germ. 

 iii. 518. C. mutahilis Roth, Cat. Bot. iii. 282. C. fas- 

 ciculata Thore, Chlor. 444. Batrachosperme en houpe, 

 Vauch. Conf. 114. pi. xii. fig. 4. et 5. ; Cand. Flor. 

 Fr. ii. 6*^. Batrachospcrmum glomeratum Cand. Syn.144. 

 C. mutahilis, Eng. Bot. t. 1470. D. glomerata Harvey, 

 in Hook. Brit. Fl. p. 388. ; in Manual, p. 121. 



This species differs in appearance greatly according to its 

 age and place of growth. The younger specimens are of a 

 herbaceous and delicate green, abundantly branched, and the 

 older ones often nearly denuded of branches and almost colour- 

 less, becoming so by the escape of the zoospores. When dried 

 on paper the differences between certain specimens of this 

 plant presented to the eye are so considerable that many 

 would regard them as varieties, and almost as species. A 

 microscopic examination would, however, at once remove 

 this supposition. 



When first removed from the water, it presents the appear- 

 ance of a mass of coloured jelly without form or organization : 

 on immersion, however, its branches soon expand. Its fragility 

 is so excessive, that frequently its own weight when fresh is 



