777 



Subdivision 2. 18 species. 

 Codiolum gregarium. 

 Percursaria percursa. 

 Monostroma Grevillei. 

 Ulothrix flacca. 

 Bolbocoleoii piliferum. 

 Pilinia maritima. 

 Ulvella fucicola. 



— confliiens. 

 Pringsheimia scutata. 

 Urospora mirabilis. 



— Wormskioldii. 

 Chætomorpha Melagonium. 

 Spongomorpha vernalis. 

 Acrosiphonia incurva. 

 Cladophora riipestris. 



— sericea. 



Ostrobium Queketti. 

 Vaucheria coronata. 



C. The boreal-arctic groiip. 

 7 species. 

 Enteromorpha inlestinalis. 

 — clathrata. 



Ulva Lactuca. 

 Chætomorpha tortuosa. 

 Rhizoclonium riparium. 

 Cladophora gracilis. 

 Gomontia polyrhiza. 



D. The cold-boreal group. 

 11 species. 

 Codiolum pusillum. 

 Prasiola crispa •= marina. 



— furfuracea. 



— stipitata. 

 Endoderma Wittrockii. 

 Acrochæte repens. 

 Acrosiphonia albescens. 



— flagellata. 



— grandis. 

 Derbesia marina. 

 Valonia ovalis. 



E. The warm-horeal group. 

 2 species. 

 Enteromorpha Linza. 

 Bryopsis plumosa. 



IV. Cyanophyceæ. 



13 species. 



Å. The ar die group. 

 O species. 



B. The siibarctic group. 

 Subdivision 1. O species. 



Subdivision 2. 1 species. 

 Pleurocapsa amethystea. 



C. The boreal-arctic group. 

 3 species. 

 Spirulina subsalsa. 

 Calothrix scopulorum. 

 Rivularia atra. 



D. The cold-boreal group. 

 2 species. 

 Dermocarpa Farlowii. 

 Hyella endophytica. 



E. The warm-boreal group. 

 7 species. 

 Chlorogloea tuberculosa. 

 Dermocarpa violacea. 

 Hyella cæspitosa. 

 Phormidium autumnale. 

 Lyngbya lutea. 

 Microcoleus tenerrimus. 

 Calothrix æruginea. 



