l'KNII'M. 33 



S. 0ONDEN8ATA, Breb. Plate III, figs. 21, 22. 



Fusiform, or cigar-shaped, ends rounded, eight to ten times 

 a- long a- broad, with a single, broad, closely wound chloro- 

 phyl spiral band, its revolutions numerous. 



Diameter 18-25 ,,., 



Pound in meadow pools, ponds, etc. Has been collected 

 in man y States of the Union, from New York and New Jersey, 

 south t< Florida, ami westward to Minnesota. 



S. 0BCDRA, Ralfs. Plate III. figs. 16-19. 



Fusiform, deep gre n, five to eighl time- longer than broad, 

 ends attenuated, apices rounded. Chlorophyl arranged in a 

 number of narrow spiral, parietal, bands. 



Diameter 81 5 ". 



The locality in which this species occurred i i frequently 



to me, was In small pool- aside streamlets on the open slope 

 nt' our mountain sides, hut found it also in New Jersey. 

 European specimens air quoted as large a- 30 .". in diameter. 

 I have found none so he 



s. bryophila, (Breb) Rab. S. muadoola, l>. By). Plate III, 

 fig. 20. 

 Cells cylindrical, two to four time- a- long as broad, ends 

 obtusely rounded, chlorophyl a single, broad, smoothly defined, 

 widelv wound spiral hand ; its revolutions one or two. 



Diameter 8 y. 



\)v. Wood nport- t hi- species, measure and form, from 

 near Philadelphia, growing among some masses which were 

 kept constantly wet by overhanging dripping rocks. It 

 formed little transparent masses of almost colorless jelly, 

 looking like little drops of dew. 



Genus, PENIUM, Breb. 



(Netrium, Naeg. Cylindrocystis Menegh.) 



Plate V, figs. 1-22. 



("ells straight cylindrical or fusiform, not incised nor constricted 



in the middle; ends more or less obtusely rounded. Chlorophyl 

 lamina axillary; when seen transversely, radiately divergent, arms 

 often forked, and containing starch granules. 



