SPECIES OF ALGvE. 39 



b. Pore above the middle (c]. 



c. Oospore not quite filling the oogonium (d). 



c. Oospore entirely filling the oogonium (e). 



d. Veg. cells 3-5 times as long as wide obsoletum, 71 



d. " " 2 -5-3-5 " " " " " .... phisiospermum, 72 



d. " " 4-10 " " " " " .... polymorphuifi, 73 



e. Veg. cells 4-5 times as long as wide ft -agile , 71 



e. " " 2-4 -zig-zag, 71 



y. Oospores subglobose, filling the oogonia . . . autumnale, 73 

 /. Oospores obovate, not entirely filling the oogonia (g). 



g. Veg. cells 4-6 times as long as wide vernale, 72 



g. Veg. cells 2-4 " " " " " crispum, 72 



h. Oogonia single, opening by a superior pore; oospore globose not 



filling the oogonium urbicum, 73 



/. Oogonia opening by a pore above the middle (/). 



/. Oogonia " " " lid ........ gracillimum, 74 



j. Veg. cells 3-7 times as long as wide paludosum, 74 



j. " " 2-5 " " " crassum, 74 



/&. Oogonia with 7-12 vertical constrictions . . . platygynum, 75 



k. Oogonia without vertical constrictions (/). 



/. Oospore globose or nearly so (m). 



1. " subellipsoid (o). 



m. Diameter veg. cells i5~i7/<, 4 times constricted . undulatum, 76 



m, " " " 28-38^, not constricted . . cataractum, 77 



m. " " " from 9-15^ (n). 



n. Oospore depressed-globose decipiens, 75 



n. " exactly globose Areschougii, 76 



<?. Dwarf males adhering to all parts of the female . multispora, 78 



o. " " on or near the oogonia cyathigerum, 77 



/. Oospore membrane smooth (q). 



p. " " beset with bristles (^). 



q. Oospores globose or nearly so (r). 



q. ellipsoid or ovate (w). 



r. Oogonia opening by a lid (s). 



r. " " " a pore (/). 



s. Terminal cell rounded Lundense, 79 



s. " " apiculate macrandrium, 80 



/. Pore in the middle or a little above (u). 



t. " above the middle (v). 



u. Veg. cells 4.5-6 times as long as broad .... flavescens, 78 



u. " " 2-4 " Braunii, 79 



