CONFERVACE^. 71 



towards all parts of the circumference, sending forth multifid coloured branches verti- 

 cally and laterally. The articulations of the filaments are once, twice or thrice as long 

 as their diameter in diiferent parts, contracted at the dissepiments, and filled with bright 

 green endochrome. In a young state the apices of the ramuli are prolonged into seta;, 

 or needleshaped, colourless acuminated cells, but these are deciduous in this and other 

 species of the genus. Colour, a bright green. 



Possibly this species is only a small state of C. elegans. 



11. DRAPARNALDIA, Bonj. 



Filaments separate, gelatinous, articulated, dimorphous ; the articulations of the 

 stem and branches hyaline, transversely banded ; those of the ramuli filled with green 

 endochrome. Zoosjwres formed in the articulations. (In fresh water.) 



Very beautiful, and extremely gelatinous, bright green, filamentous, much branched 

 Alga;, found in clear wells and gentle streams. The structure of the filaments is similar 

 to that of the filaments of the Chcetophorce ; and this genus merely differs from the 

 preceding in its filaments being separate one from another, and not combined by means 

 of gelatine into a compound frond. It therefore bears the same relation to Choitophora 

 that Vaucheria does to Codlum. The name was bestowed by Bory de S. Vincent in 

 honour of M. Draparnaud, a French naturalist. 



1. DRAPARNALDIA opposita, Ag.; frond vaguely much branched ; joints of the main 

 filament as long as broad, or shorter ; pencils of ramuli mostly opposite, densely set, 

 lanceolate-acuminate in outline, plumose, bi-tripinnate, the apices much attenuated. 

 Ag. Syst. p. 59. Kiltz. Sp. Alg. 357- Lyngh. Hyd. Dan. tab. 65, Jig. A. Batra- 

 chospermum Americanum, Schweinitz. 



Hab. In clear streams. New York, Professor Bailey. New Jersey, 3Ir. Jackson. 

 (v. s.) 



Frond 2-3 inches long, gelatinous, capillary, irregularly much branched ; the branches 

 patent, lateral, more or less divided, and set with lesser ramuli. Main filaments with 

 short articulations, as long as their breadth or shorter, transversely banded. At every 

 two or three nodes and sometimes at every node a pair of opposite penicillato-multifid 

 ramuli are thrown off. These are bright green, ovato-lanceolate in outline, much 

 acuminated and twice or thrice pinnate, their pinnules somewhat constricted at the nodes, 

 and tapering at the apex into long, needle-like, hyaline points. Their cells are com- 

 monly nucleated and filled with endochrome. 



Whether this be permanently distinguishable from D. glomerata is doubtful. It has 

 externally the aspect of that species, but its microscopic characters are nearer those of 

 D. piumosa. 



