V 
DESCRIPTION OF PLATES 243 
4-6. Stichococcus en e the variation in the length of the cells, 
and the coccoid state (531), p. 
7-9. Stichococcus SZ EEN breaking up, and the coccoid state (575), 
10-13. Stichococcu rivularis. Terminal and intercalary rhizoidal hooks (568), 
66 
PLATE 23 (575:1) 
I. Microspora amoena. (447 A), p. 170. 
2.. Microspora crassior. (620), p. 169. 
3, 4. Microspora Loefgrenü. (351, 447 B), p. 171. 
5. Microspora Wittrockit. (348), p. 172. 
6 filament from the same material, showing the structure of the cell-wall after 
prolonged preservation in pyroligneous-acid-formol solution, 
of the H units of the cell-wall. 
PLATE 24 (575:1) 
. Microspora Er A filament with greater diameter and more inflated cells 
than nis : 349), p- 
pical hae in active growth, with somewhat reduced chromatophore 
(409). 
3. A filament containing zoöspores (599). 
Akinetes and two dead cells (283 A). 
ی و و‎ Willeana. A vegetative filament, with dead cells at top and bot- 
tom Ge p- 17 
u or dead zoöspore, adead cell, and an akinete (609). 
S End of a ہہ‎ <7 SE (609). 
8,9. Microsp Vegetative filaments (600, 679), p 
The 700 of the cell-walls brought out by prolonged کت‎ in pyro- 
er و‎ solution 83 C). 
II. Formation of akinetes (573 A). 
12. poet stagnorum. Vegetative filament and zoöspore formation (495) 
6 
I = A vegetative filament with long cells (66). 
Microscopa quadrata. End of a filament from material which formed a furry 
contig on sticks in an aquarium (669), p. 178. 
. Filament from a confervoid mass (423). 
PLATE 25 (575:1) 
I, 2. Tribonema bombycinum. Varying forms of vegetative cells (430, 421), 
p- 184. 
3. Cells pulling apart for dispersal of zoóspores (128). [This single figure was 
originally drawn from living material with ocular 3 and objective 7, and later was en- 
larged to the scale of the rest of the plate.] 
Tribonema veer Es tenue. A filament drawn at the time of collec- 
tion, October 19th (499 A), p. 
om the same material, sedis October 3oth, showing the change in the chro- 
۱۳9 ی‎ produced by better nutritive conditions. 
6. A common form (443 B). 
7, 8. Tribonema minus. (443 C, 428), p. 186.. 
