106 BATRACHOSPERME^E. 



Conf. gelatinosa Dillw. Brit. Conf. Bat. ludibundum (var. 

 confusum) Bory, in Annales du Museum, vol. xiv. p. 320. 

 pi. 29. fig. 3. no. 63. ; Gir. Chantrans. Mycros. p.|175. 

 pi. 25. 



Hob. Lea well, Devonshire : W. H. Harvey. In a 

 small brook in Clive Wood, Swansea : Dillw. 



Under the name of Batrachospermum ludibundum Bory de- 

 scribes seven different varieties of Batrachospermum: many of 

 these are indigenous to Great Britain, and several of them 

 doubtless, are distinct species, in which light the plant under 

 consideration ought to be regarded. 



" This variety is not rare ; it grows in the closed basins of 

 very pure and cold fountains. It there appears to choose 

 shady places. It is found in the holes of rivers, whose waters 

 carry no mud. I have observed it in France, in Spain, in 

 Germany, in Poland, and in Ducal Prussia. 



" Of all Batrachosperms, this acquires the greatest dimen- 

 sions : its length is sometimes four inches and a half, its dia- 

 meter equal often to that of the culm of grasses. Its branches 

 appear also to be less obtuse than in the following varieties. 

 The globules or whorls are so approximated and so large 

 that they are often confounded together in such a manner, 

 as to be with difficulty distinguished in certain specimens 

 which have the aspect of Batrachosperma helmintosa. The 

 colour of the plant is of a mouse grey, agreeable by its trans- 

 parency. The large stems approach a little upon yellow. 

 These tints become of a beautiful violet by putrefaction. 



" It is upon individuals of the variety which now engages 

 us that I made, for the first time, twelve years ago, an experi- 

 ment which ought to be known ; after having many times car- 

 ried from one locality to another stones bearing individuals of 

 this species, which continued to prosper in spite of the change 

 of habitation, I steeped many of them in lukewarm water, 

 afterwards in boiling, and no part of the batrachosperm ap- 

 peared, under the microscope, to have undergone the slightest 

 disorganization by these immersions, and certain sprigs replaced 

 in their native place continued to vegetate after these experi- 



