DEDIFFERENTIATION IN PEROPHORA 697 
the test (x) did not change, and a space was left between it and the ecto- 
derm when contraction occurred. Note the thickened epithelium in con- 
traction, with irregular outline externally. Note the small outgrowth 
in the expanded state; this was not observed after contraction. The 
stolon remained for a few minutes contracted, then expanded in under 
a minute ; and vice versa. The blood-cells are not figured. 
Fig. 25 (x 340).—A large lateral outgrowth, on the same stolon as that 
shown in fig. 24. The blood-cells are shown in the outgrowth itself, but 
only a few indicated elsewhere. 
Fig. 26 (x340).—A normal growing stolon-tip. Note the columnar 
epithelium at the extreme tip. Close to the tip there are very few green 
blood-cells, the majority being white. Then comes a zone where a con- 
siderable proportion are green, and then one where they are in the majority. 
The circulation, though active, did not extend into the densely-packed 
region drawn. 
Figs. 27 and 28.—Dedifferentiation in Amaroucium. 
Fig. 27 (x 80).—A young oozite in stage 2-3 of reduction. The dense 
anterior mass was orange-red. Portions of the intestine are seen below. 
Muscular contraction of the whole organism still took place at intervals. 
Fig. 28 (x 80).—A blastozooite dedifferentiated in weak alcohol, stage 3. 
Note the cell-masses outside the main body of the organism. 
