CATALOGUE OF PLANTS. 615 
RHAPHIDIUM, Kutz. 
R. polymorphum, Fres. 
In stagnant waters. 
R. convolutum (Corda), Rab. 
Same habitat. 
DIMORPHOCOCOUS, A. Br. 
D. cordatus, Wolle. 
Free-swimming in ponds, 
EHREMOSPH.AGRA, De By. 
H. viridis, De By. 
In small pools; frequent. 
(PLEvROcoccus is not regarded as a valid genus.) 
- 
CHYTRIDIE. 
(An order of questionable affinities.) 
CHYTRIDIUM, A. Br. 
C. acuminatum, A. Br. 
C. globosum, A. Br. 
Parasitic on various fresh-water alge. 
CLASS 3.—ACHLOROPHYLLE. 
SACCHAROMYCETES. 
(Ferments.) * 
SACCHAROMYCHES, Meyen. 
S. cerevisize, Meyen. 
The Yeast Plant, which causes the fermentation of saccharine 
solutions, producing alcohol with the accompanying disengage- 
ment of carbonic acid gas. 
* Only the most common and best-known forms are here enumerated. 
