388 
Fic. 
FIG. 
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Fic. 
WILSON. 
EXPLANATION OF PLATE XVI. 
(Esperella fibrexilis.) 
20. The ovarian egg of Fig. 20’, with neighboring tissue. D.4. 
Gemmule breaking up or “segmenting.” Section. D.4. 
Section through a gemmule near the close of “segmentation.” D.4. 
Part of a section through a gemmule, entirely broken up into 
separate cells. D.4. 
Fic. 24. Longitudinal section through gemmule, in which the posterior pole 
is differentiating. C.4. 
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Cre 
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Fic. 
Fic. 
BIG: 
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Fic. 
25. 
ww Ww oe nb bw HN N 
rm) 
SO Oona 
om 
Longitudinal section through gemmule larva, still in body of parent. 
Surface view of swimming larva shortly after birth. A.4. 
Surface view of swimming larva 36 hours after birth. A.4. 
Surface view of incompletely metamorphosed larva. A.4. 
Longitudinal section of larva shortly after birth. D.4. 
. Longitudinal section of older larva. D.4. 
Ectoderm cells of swimming larva — maceration products. 
Parenchyma cells of swimming larva — maceration products. 
