30 MARCUS M. HARTOG. 
The Bancraces® differ, however, little in the essentials 
of gametogeny from those protophytes which they resemble so 
closely in vegetative growth. In Bangia the spermatogo- 
nium undergoes repeated bipartitions accompanied by cell- 
wall formation ; finally, the cell bodies undergo two further 
bipartitions, and become free as four naked spermatia. The 
oogonia produce oospheres by bipartition, which are cells 
with a narrow anterior receptive apex and a dilated base 
containing the nucleus. A spermatium sticks to the narrow 
end (trichogyne), and conjugates with it, and the spermato- 
nucleus passes down, we may suppose, to fuse with the 
oonucleus. The basal protoplasm then contracts to form the 
zygote, while the upper part takes no further share in its 
life. The trichogyne is here obviously comparable to the beak 
in Vaucheria or G@idogonium. Porpuyra differs in minor 
points only from Banera. 
In the true FLoripr# the spermatia! are formed, not by 
ordinary fission, but by budding and abstriction, and are 
uninucleate. In every case they are borne on a persistent 
basal cell, whose nucleus divides, one daughter-nucleus passing 
into the budded cell, the other remaining in situ. We may 
distinguish two modes, which can again be subdivided. 1. The 
budded cell undergoes (one or) two mitotic divisions to form 
four spermatia, all of the same generation, and grandnieces of 
the basal cell: (a) the divisions are crucial and the spermatia 
are collateral, resting on the basal cell (Polyides); (6) the 
divisions are horizontal, and the spermatia form a vertical 
file(Hypnea). 2. The basal cell repeats the former process 
of budding, so that the spermatia are of successively lower 
generations, and the youngest is sister to the ultimate 
basal cell: (a) the buds are collateral and all spring 
directly from the basal cell (Chondria); (b) the buds are 
intercalated in turn between the basal cell and the next older, 
so as to form a basipetal file like the conidia of many Fungi 
(Melobesia). 
1 The following account is taken from Guignard, ‘“ Développement et 
Constitution des Anthérozoides,”’ in ‘Rev, Gén. de Botanique,’ vol. i, 1889. 
