BULBOCHAETE 
bo 
“I 
OEDOGONIACEAE De Bary 
1854, p. 94; Pringsheim 1858, p. 68; Wittrock 1874, p. 6; Hirn 1900, p. 71; 
Collins 1909, p. 222. 
Plants aquatic or terrestrial; filaments simple or branching; 
cells uninucleate; chloroplast parietal, generally in the form of a 
reticulum, with one or more pyrenoids; cell division by the 
rupture of a ring-like thickening on the inner wall of each cell 
near the apex. Reproduction asexually by multiciliate zoo- 
spores, formed singly by the vegetative cells, germinating 
almost immediately. Reproduction sexually by eggs and 
sperms in oogonia and antheridia; oogonia single or in groups, 
arising as a result of division of a vegetative cell, opening by a 
pore or a lid, through which the sperm may pass; the egg when 
fertilized becomes the oospore, with a wall of one to three layers, 
which after a period of rest produces four zoospores. Antheridia 
either in the same filament as the oogonia or in separate fila- 
ments; male filaments approximately the same size as the 
female, or much smaller (‘‘dwarf males’’); dwarf males, arising 
from the germination of androspores, are epiphytic usually 
on or near the oogonia, sometimes scattered; sperms one or 
two in each antheridium. 
KEY TO THE GENERA. 
lig [Evi evaave ayes biol eyez havels\eto| cian on a aomeooR Cam ecco cene III. Oedogonium (p. ey, 
Pea iremicMb ranchers ee ciccrs cosa ce ca se cc enEe ee dc. ct dere os = seen 
2. Vegetative cells with laterally placed setae.... I. Bulbochaete (p. a 
2. Vegetative cells devoid of setae................ II. Oedocladium (p. 51) 
Genus I. Bulbochaete Agardh 
1817, p. XXIX; Pringsheim 1858, p. 71; Wittrock 1874, p. 43; Hirn 1900, p. 321; 
Collins 1909, p. 266; Tiffany 1928, p. 129. 
Filaments usually attached, branched, the branches unilateral; 
vegetative cells normally widening upwards; basal cell ordinarily the 
only one capable of division in formation of main axis, first new cell 
forming a long tubular bristle with swollen bulb-like base, subsequent 
cells intercalated between basal cell and next one above; rarely division 
is intercalary; other vegetative cells potential origin for side branches; 
terminal cell of each branch always furnished with a bristle; oogonium 
arising by a double division of a vegetative cell. 
