6o SPECIES OF ALGjE. 



V. " s (ii). 



V. " 6 or more {Jj). 



w. Spore-bearing cells inflated, spore elliptic or ovate, elongata, 221 



w. " " " not or only slightly swollen (pc). 



X. Filaments 32-40/4 in diam. decimina, 216 



X. " 43-50/^ " "... . dubia, 217 



X. " 55-60/^ " " subaqua, 220 



;>>. Mature spores yellow, oval, ^ longer than wide . neglecta, 216 

 y. " " not yellow {z). 



z. Diameter of filaments 90-100/4; spore oval . . . jugalis, 219 

 z. " " " 40-65/4 (a(j). 



32-36/^ (dd). 



aa. Spore orbicular, flattened . . orthospira 218 



aa. Spore not flattened (bb). 



bb. Spore spherical or broadly ovate . . . subczqua, 217 



bb. Spore not elliptical or ovate (cc). 



cc. Spore oval-elliptical or subcylindrical . . dubia, adnata, 220- 



cc. Spore oval or subglobose, spore cells 2-4 times longer than wide, 



majuscula, 221 



dd. Sterile cells 7-1 1, fertile cells about 4, times as long as wide, 



rivularis, 220 



ee. Spore-bearing cells much inflated, spore oval, 80/t long, 



fluviatilis, 216 

 ee. " " " slightly or not inflated (77)- •, 



ff. Spore flattend, orbicular orthospira, 218 



ff. Spore not flattened i^gg). 



gg. Diameter of filaments 150-156/1 . ... crassa, 219 



gg. " " " io2-iio/t setiformis, 219 



gg. " " " 90-100/1 ..'.... jugalis, 219 



gg. " " " 72-78/1 (M). 



M. Chlorophyll bands making 1-4 turns in each cell . nitida, 217 

 hh. " " " I ^ " spore 50/1 wide, 



parvispora, 221 

 ii. Spores flattened, orbicular, membrane smooth . . orthospira, 218 

 ii. Spores " " " punctate or porose, 



bellis, 217 

 jj. Filaments of two widths, one 125//, the other 80/t, inmqualis, 218 

 jj. " of equal width (kK). 



kk. Diameter 150-156/1 crassa, 219 



kk. " 118-125/1 maxima, 218 



kk. " I02-II0/1 setiformis, 219 



kk. " 54-62/1 majuscula, 221 



