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Classification of Green Algce . 
Fam. IV. Chlorococcaceae. 
Plant-body a single cell or coenocyte of simple form, free or 
epiphytic. Chromatophore nearly always a single parietal plate and 
containing one pyrenoid. 
Reproduction only by the formation of zoospores in all the forms. 
Gamogenesis never yet observed. Vegetative division found only in 
palmelloid stages. 
[The first three genera form a natural series which may be regarded 
as derived from the Chlamydomonas-type by the evolution, fiom its 
characteristic continuous succession of walled motile cells, of a type in 
which this sequence has differentiated inlo an alternation of naked 
motile cells (zoospores) and walled non-motile cells (the plant bodies).] 
Genera. 
1. Chlorococcum. Meneghini. 
Plant body round, coenocytic when adult, floating or 
attached to a substratum and then often polygonal by 
compression — the result of a number of zoospores 
having come to rest close together. Zoospores eight 
or more from each cell. 
2. Sykidion. Wright, 1879. 
Cells globular or ovoid, attached singly or in clusters, 
nucleus always single. Two or four zoospores may 
arise in any cell and escape by the detachment of a 
special lid. 
3. Characium. A. Braun, 1849. 
Plant body ovoid or cylindrical, erect or oblique, often 
beaked, attached singly by a definite mucilaginous 
stalk. Zoospores several in a cell, sometimes 
liberated by the detachment of a special lid. 
4. Dicranochaete. Hieronymus, 1887 
Cells hemispherical, attached by the flat surface to 
water plants. Chloroplast single with one or several 
pyrenoids ; nucleus single. Zoospores 4-32, liberated 
by the detachment of a special lid. A remarkable 
large, tubular richly-branched filar structure grows 
out from the base and spreads out above the organism. 
5. Halosphaera. Schmitz, 1878. 
Cells very large and spherical, floating freely in the sea. 
Chloroplasts of numerous parietal discs ; nucleus single. 
Zoospores many from each cell, of unusual form with 
flagella arising from the broad end. 
[The affinities of this genus are by no means clear, hut the absence 
of vegetative division seems to indicate its inclusion in this family.] 
Fam. V. Endosphaeraceae. 
Plant-body a simple spherical cell or a slightly branched coenocijte . 
Reproduction by the formation of zoospores cr of planogametes 
