Fio. 2, Zygogonium cvicetorum : A, early stage in process of fusion of gametes 
—for description see text; the contents of each gametangium has shrunken 
somewhat owing to the mounting ; B, mature zygospore ; C, ditto, free from 
the “conjugation-canal”; D, crossed zygospores —seetext; the contents of the 
topmost zygospore has been omitted in order to show the outline of the lower, 
which is immature ; E, three successive stages (from right to left) in the 
developmentof an azygospore; the mature azygospore is seen on the extreme 
left; F, young filament of two cells produced by the germination of a 
zygospore, and attached at one end to one of the conjugating filaments. 
AH X 600. 
