14 
GENERA OF NORTH AMERICAN PLANTS. 
Chondria . . 1 
Spheerococcus . 17 
Halyraenia . 4 
Delesseria . 5 
Tribe VI. Fucoidece. 
Lemania . 2 
Chordaria . 1 
Scytosiphon . 1 
Sporochnus . 4 
Zonaria . 1 
Laminaria . 10 
Furcellaria 
Fucus 
Cystoseira 
Sargassum 
