140 Blackman and Tansley. 
v*The upright branches few and only slightly branched, the basal 
plate preponderating. Branches sometimes ending in 
unicellular hairs. 
4. Endoclonimn. Szymanski, 1878. 
Thallus-form various, usually an irregular basal plate 
of polygonal cells, produced by concrescence, and 
bearing erect or ascending free branches which may 
end in unicellular hairs. Epiphytic or endophytic. 
Quadri-flagellate zoospores and bi-flagellate gametes 
(?) occur. 
5. PseuJcndoclonium. Wille, 1901. 
Thallus epiphytic, a small irregular basal plate with 
upright or rhizoid-like free branches of one or a few 
cells ; no tapering branch-ends. Chloroplast a parietal 
plate only occupying a small part of the cell. 
Zoosporangia round and opening with a very short 
neck. Zoospores quadri-flagellate without eyespots. 
6 . Epicladia. Reinke, 1879. 
Thallus abundantly branched, the central part cohering 
to a pseudo parenchymatous plate, the peripheral 
branches flee and without tapering ends. Chloroplast 
may line the whole cell. Reproduction by zoospores. 
*** Thallus an irregularly branched, creeping, endophytic, elongated 
axis, beaiing short erect branches, which end in hairs or 
setae. 
7. Chaetonenia. Nowakowski, 1876. 
Thallus an elongated sparsely branched creeping 
endophytic axis bearing short erect branches which 
terminate in unicellular hairs. Cells elongated not 
crowded. Quadri-flagellate zoospores alone observed. 
8. Bolbocoleon. Pringsheim, 1862. 
Thallus an elongated endophytic axis bearing numerous 
short erect branches, all the cells of which bear setae. 
Zoospores bi-flagellate. 
9. Acrochaete. Pringsheim, 1862. 
Thallus as in Chaetonenia , but the erect branches are 
very short and unicellular, or only unseptate processes. 
Branches end in setae, with a thickened basal wall. 
Probably both zoospores and gametes occur. 
----Thallus a creeping branched endophytic or epiphytic axis without 
erect vegetative branches, but bearing erect hairs or setae. 
10. Aphanochaete. A. Braun, 1851. 
Thallus a creeping epiphytic branched axis bearing 
upright unicellular hairs. In cultures the hairs may 
revert to ascending branches. 
