70 
Blackman and Tans ley. 
[This group seems also to he derivable from the Chlamydomonas- 
type, and in the simplest genus, Chloraugimn, only a few sessile 
generations become aggregated before tne cells all revert (as zoospores) 
to the motile condition.] 
5. Chloranginm. Stein. 
Colony a widely diverging branched system of only a few 
segments. Chloroplasts two, lateral ( a departure 
from the chlamydomonad type possibly evolved by 
halving). 
6. Ecballocystis. Bohlin, 1897. 
Colony of very closely compressed branchings, the 
successive mother-walls largely superposed. 
7. Prasinocladus. Kuckuck, 1894. 
Colony of oval clustered cells attached by short mucila¬ 
ginous stalks. Chloroplasts at first several in a cell¬ 
fusing to one later. 
***Filawentae. 
Colony taking the form of a branched or unbranched mucila¬ 
ginous cylinder in which the cells are imbedded as a central 
series, usually at some distance from one another. 
8. Radiojiluni. Schmidle, 1894. 
Colony an unbranched cylinder. Cells in close contact* 
with their long axes at right angles to the axis of the 
cylinder. 
9. — Hormospora. Brebisson. 
Colony as in Radiofilum but the long axes of the cells 
are parallel to that of the colony and the cells are 
further apart. 
10. — Hormotila. Borzi. 
Colony a cluster of mucilaginous cylinders branching in 
any direction. Cells large and globular, cylinder 
narrower between the cells 
11. — Hauckia. Borzi. 
Colony dichotomously branched, the successive members 
attached to the older ones by short mucilaginous 
stalks. Cells oval, cylinder of uniform width. 
* * * * C hlorospJiaerea e . 
Cells living singly or loosely associated in an indefinitemncila- 
ginous investment. 
12. — Chlorosphaera. Klebs, 1883. 
Cells spherical with a stellate or reticulate chromatophore. 
usually containing several pyrenoids. Transverse 
