DEDIFFERENTIATION IN PEROPHORA 665 
than in blastozoites, and appeared to be a healthier process 
unaccompanied by so many abnormal swellings of the test, 
extrusions of parts of zooids, phenomena of local decay, &e. 
Treatment with Alcohol.—A few experiments were 
made to test the effect of a 2 per cent. solution of alcohol 
on the process. Jt appeared that under its intluence, dedif- 
ferentiation, both in oozoites and blastozoites, started sooner 
TExtT-Fic. 1. 
Reduction in oozites of Amaroucium. 
A. Zooid in stage 3, test spherical, test of tail degenerating, 
B. As A, except that the zooid shows detached cell-masses, and 
lies in a spherical portion of test detached from the rest. 
than in the controls, but that it did not progress in a normal 
way. Opacity might be attained, but the loss of form, especially 
in the pharynx, was not as great as usual, e.g. the siphons 
remained visible relatively much longer after their retraction 
from the test than in normally-reducing specimens (fig. 28). 
This appears to indicate that there are two distinct pro- 
cesses at work in normal deditferentiation, the first bemg a mere 
shrinking as a result of exposure to an unfavourable environ- 
ment, the second a real despecialization of the cells, resulting 
in loss of typical form. This latter then is due to active positive 
