75 



CHLOROPHYLLOPHYCE.E. 



165. Individual plants one or two celled. 168 

 Individual plants composed of many cells. 



Thallus consisting of threads jointed throughout. 166 

 Thallus membranous or thread-like and not jointed throughout. 



Thallus membranous, leaf -like, or formed into an irregular sac or 

 tube. Cells minute, in vegetation dividing into twos or fours. 



ULVACEJS. 



Frond consisting of a simple or branched smooth thread, with 

 whorls of jointed branches. Having root-like projections at base. 

 Growing in salt water. DASYCLADE.E. 



Cells inflated. Frond consisting sometimes of one large, long cell, 

 sometimes of several cells cohering into a long thread or honey- 

 combed membrane. The threads sometimes cohere into a net 

 work or a leaf -like expansion. Growing only in salt water and 

 in warm climates. VALONIACE^E. 



166. Threads not branched. Cells very long, cylindrical, all alike. 



Chlorophyll arranged in ring-like bands. Spores formed in one 



cell very numerous. SPH^EROPLEACE^;. 

 Threads sometimes simple, sometimes branched. 167 

 Threads always branched. 



Growing in the air. Filled with red or orange coloring matter 

 equally distributed. Having a smell of, violets. 



CHROOLEPIDACE^E. 

 Growing in water. Green. 



Branching by twos. Terminal cells appearing as long, colorless 

 hairs. Imbedded in mucus. CH^ETOPHORACE^:. 



Branching variously. Threads bent in the middle, pointed at the 

 ends. Genus Asterothrix. 



167. Cells all alike, not surrounded by mucus. Green matter, some- 

 times uniformly distributed, sometimes variously grouped. (The 

 exact place of this family is still uncertain.) CONFERVACEJE. 

 Cells not all alike, showing a peculiar cap-like arrangement at the 

 ends during vegetative division. Cells short. (EDOGONIACE*. 



