694 JULIAN S. HUXLEY 
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ILLUSTRATIONS. 
All figures are drawn to scale with the Abbé Camera lucida. 
Otherwise they are semi-diagrammatic. All were drawn at 
table level ; the magnification is indicated for each figure. 
Fig. 1.—Clavellina type of reduction (x25). Two zooids, a and B, 
isolated without stolons. a. Day of operation. B has a trace of stolon- 
connexion. 6. After forty-eight hours. Reduction started earlier in 
B. Both have formed short stolons, but that of B remains within the test. 
A has only just started to reduce. c. Advanced reduction (three days for B, 
four days for 4). The stolon of B is large and lobulated, but has not emerged 
from the test. B is spheroidal and opaque, in stage 4-5. A is in stage 3, 
which it did not reach till after three days. Its stolon has grown, and is 
distended with cells. a’s heart was beating slowly, B’s had almost stopped. 
Figs. 2 and 3,—Growth or maintenance of zooid at expense of stolon, 
