Classification of Green Algoe. 141 
Zoospores of different sizes occur and heterogamy has 
been observed. The female planogamete is large, 
round, quadri-flagellate and sluggish, the male is small, 
pyriform, active, with four flagella and very little 
chlorophyll. 
11. Gonatoblnste. Huber, 1892. 
Thallus as in Aplianochaeie but the young cells bearing 
erect setae which secondarily become occluded and 
displaced by further growth. 
Zoospores quadri flagellate. 
12. Endodcvma. Lagerheim, 1883. 
Thallus very various, a creeping branch system without 
erect branches, either endophytic with swollen cells 
straggling branches and no setae or growing as a dense 
cluster in wall of host, or epiphytic with setae, and 
ultimately growing to dense cushions by superposition 
of branches. 
Zoosporangium opening by a small tube, zoospores 
quadri-flagellate and also bi-flagellate (? gametes). 
13. Phaeophila. Hauck, 1876. 
Thallus endophytic or epiphytic, a much branched 
creeping axis with no erect vegetative branches. 
Setae one or two to each cell spirally twisted, second¬ 
arily occluded. Cells sinuous elongated. 
Zoospores emitted through a long tube, and gametes 
probably also occur. 
14. Ocldochactc. Th waites, 1849. 
■ ■ \ 
Thallus an epiphytic cushion of compressed branches 
which may be two or three layered by superposition of 
branches. Each external cell may bear a seta or very 
few may be present. 
Zoospores liberated through a tube. 
Thallus a pseudo-parenchymatous disc produced by the con¬ 
crescence of a branch-system, and without erect branches. 
Setae or filar processes are usually present. 
[Some of the genera placed in this last group have been withdrawn 
from the family Ulvaceae, which is to be characterised by truly paren¬ 
chymatous growth and by the restricted attachment of the thallus. All 
the genera included in the present section grow by concrescence of cell- 
branches and are attached by the whole surface of the thallus.] 
15. Pringsheimia, Reinke, 1889. 
Thallus an epiphytic plate of a single layer of deep 
cells very closely coherent with a well defined outline, 
a general mucilaginous investment and projecting 
setae (sometimes absent). Bi-flagellate zoospores and 
gametes occur. 
