Pl.cell.aph. 1. HYDROPHYTES. 24. Draparn. 303 
2. Draparnaldia plumosa. Feathery draparnaud . 
Threads very much branched; branches in bundles, m any- 
cut, pencilshape, mostly opposite, lanceolate, acute, up- 
right ; joints rather longer than broad, with a transverse 
band. 
Batrachospermutn plumosum, Voucher, 113. 
Conferva mutabilis, Roth Cat. 1, 197. 
Draparnaldia hypnosa, St. Vincent. Ann. Mas. 12,405. 
Draparnaldia plumosa, Agardh Disp. ed. 1,42. 
On woods and stones in rivers ; annual ; summer. 
Tufts three inches long; last division of the branches 
much the longest. 
XXV. 25. CONFERVA. Pliny. CrowsilL 
Threads uniform, simple or branched, greenish, jointed ; 
knots pellucid; spores granular, enclosed in the joints. 
a. Plant greenish , sunk, branched. 
1. Conferva lubrica. Slippery crow silk. 
Threads very much branched, very slender, minute, ge- 
latinous, slippery, green; branches divaricating, scattered, 
close, awlshape; tip long, transparent; joints 2 or 3 times 
as long as broad, with a central, transverse band. 
Conferva lubrica, Dillwyn, 57 ; Engl. Rot. 2087. 
Draparnaldia tenuis, Agardh Decad. 3, 30. 
On wood and stones in rivers or stagnant waters; summer. 
Tufts glaucous green, dense, 1 or 2 inches long; threads 
weak, flaccid, attenuated. 
(3. exigua. Threads less than a quarter of an inch long; 
joints about as long as broad. 
Conferva exigua, Dillwyn Syn. 62. 
2. Conferva protensa. Extended crow silk. 
Threads branched, slippery, green; branches diffused, 
very long, attenuated ; tip pellucid ; joints rather longer 
than broad. 
Conferva protensa, Dillwyn , 67. 
3. Conferva nigricans. Blackish crowsilk. 
Threads forked, rather stiff, straight, thick, equal; branches 
distant, long, spreading at bottom ; joints 4? times as long 
as broad. 
Conferva nigricans, Roth. Cat. 3, 277 ; Dillwyn , 63. 
Ponds. 
