300 19. Serpent. 1. HYDROPHYTES. PLcelLaph. 
1. Serpentinaria cmnpressa . Compressed serpentinare . 
Threads brittle, bent, coupling; joints three times as long 
as broad ; granules in a compressed mass. 
Conferva serpentina, Muller N. Act. Petr. 3. 
Conjugal a serpentina, Vaucher , SI. 
Conferva genufiexa, Dillicyn Intr. 18. 
Zygnema compression, Lyngbye Hydr. Dan. 171. 
Stagnant waters. 
Threads as line as human hair, very brittle; spore glo- 
bular, in the transverse tube. 
2. Serpentina geimflexa . Knee-lent serpenlinare . 
Threads brittle, knee-bent, coupling; joints four times as 
long as broad, half filled with granules. 
Conjugata angulata, Vaucher , 79. 
Conferva genuflexa, Roth Cat. 2, 199; Engl. Bot. 1914. 
Conferva serpentina, Muller N. Act. Petr. 3, 92. 
Conjugata genuflexa, Agardh Disp. ed. 1, 28. 
Zygnema genuflexion, Agardh Syn. 98. 
Ditches and stagnant waters; spring and autumn. 
Tufts dense, floating; threads as thick as human hair, 
slightly curved or knee- bent; granules entirely or half filling 
the joints ; spore globular, in the transverse tube. 
G. HYDRODiCTVONiDEiE. Thallus cylindrical, thread- 
shape, tubular, jointed, anastomosing like a net; ineshes 
many-sided, each side formed of a single joint \jpore P or 
emlrio ? like the parent, reticulated, contained with the 
joints. 
XX. 20. HYDRODICTYON. Roth. Water-net. 
Threads jointed, membranaceous, woven into the form 
of a purse-net; spared same form as the parent plant, en- 
closed in each joint. — Fresh-water; green. 
Hydrodictyon utriculatum. Bottle water-net . 
Threads united into a tubular net. 
Conferva reticulata, Raii Syn. 59, 10 ; Lin. Sp. PI. 1635; Engl. Bot . 
1687. 
Hydrodictyon utriculatum, Roth FI. Germ. 3, 531. 
H\drodictyon pentagonum, Vaucher , 88. 
Hydrodictyon rnajus, Roth Cat. 2,2.38. 
Hydrodictyon tenelium, Roth Cat. 2,239. 
Stagnant, or slightly flowing waters; annual. 
Plant forms a dense stratum, floating, from 2 inches to 
^ feet long ; 7iieshes mostly 5-sided, rarely 4 or 6-sided. 
