ACOTYLEDONS. ALG^E. Batrachospermitni. 77 



purple or green. They propagate by various means, eith&r ly 

 granules, which fall out on the bursting of the filaments, or, 

 after the union oftwojilamtnts ly the granules of two arti- 

 culations collecting into one ', or, ly an articulation giving 

 origin to a neiv individual, and, as it were, viviparous ; or, 

 ly seeds included in a capsule or immersed in gelatine. 



5. DRAPARNALDIA. 



Frond gelatinous. Primary filaments jointed, with penicellate 

 branchlets. Granules internal. Fronds very gelatinous, and 

 formed of conferva-like^/owze7z/5 of two kinds, of which one 

 is penicelliform, and, as it were, parasitic on the other more 

 simple one. The primary filaments are equal, jointed ; the 

 articulations pellucid, marked with a green transverse zone. 

 Secondary filaments in pencil-shaped fascicles, with short ar- 

 ticulations scarcely distinct, terminated by a long, acuminated, 

 pellucid point. Fruit ; none external, but the species are pro- 

 pagated by granules included in the articulations. They have 

 a most elegant appearance on paper, resembling a beautiful 

 drawing, and adhere firmly by their own tenacity. 



1. D. glomerata, pencils of branchlets ovate obtuse patent. Ag. 

 p. 124. Batrachospermum glomeratum, Vauch. Conf. t. 12. 

 /. 1. Conferva mutalilis, E. B. t. 1746. 



HAB. Margins of lakes, clear ditches, and streamlets, attached to 



stones and aquatic plants. 

 Very gelatinous in tufts of 2 or 3 inches in length. Primary branches 



pellucid, rather thick ; secondary ones small, much pencilled, with 



the branchlets spreading, in which respect it differs principally from 



the following. 



2. D. plumosa, pencils of the branchlets lanceolate acute erect. 

 Ag.p. 124. Batrachospermiim plumosum, Fauch. Conf. t.\\. 



f. 2. Conferva mutalilis, Dillw. Conf. t. 12. 

 HAB. The same situations as the last. 



6. BATRACHOSPERMUM. 



Frond gelatinous. Primary filaments jointed, branchlets ver- 

 ticillate. Gemmce external. Fronds very gelatinous, branch- 

 ed, often moniliform, composed ofjilaments of two kinds. The 

 primary ones resembling the more simple Confervce, jointed, 

 equal ; and filaments or Iranchlets arising from their joints, 

 whorled, divided, moniliform. Fruit; gemmcB ? or seeds, 

 external among the Iranchlets. 



1. B. moniliforme, frond alternately branched moniliform, 

 branches attenuated. Ag. p. 122. Batrachospermum moni- 

 liforme, Fauch. Conf. t. 1. /.5. t. 1 1. /. 1 and 3. E. B. 

 t. 689. Dillw. Conf. t. 32. 



HAB. Clear running streams, not uncommon. 



