PLATE 1 
EXPLANATION OF FIGURES 
All figures have been drawn with the aid of the camera lucida. The magnifica- 
tion indicated is the original magnification, the figures as they appear in the plate 
have been reduced to three-fourths the original size. 
2 Primitive egg cells in the pedicel of the gonophore, arising from entire ento- 
derm cells.  X 1900. 
3 and 4 Egg cells in the pedicel of the gonophore. These have been formed 
from the basal half of a divided epithelial (entoderm) cell. The chromatin of 
the nuclei arranged in loops. x 1900. 
5 Egg cell passing along the pedicel into the gonophore. The chromatin has 
lost its polar arrangement and has formed a reticulum in the nucleus. X 1228. 
6 Egg cell in position in the gonophore. Beginning of chromatin emission. 
x 715. 
7 Egg grown to about one-fifth its mature size. Nucleolar fragmentation 
shown, chromatin emission taking place. X 1228. 
8 Egg about one quarter grown. Shows nucleolar fragmentation and vacuoli- 
zation; chromatin emission; beginning of yolk formation. X 1228. 
9 In addition to the features shown in figure 8, this egg shows the granules of 
the cytoplasm arranged in radial lines, an indication of outgoing currents from the 
nucleus. X 1228. 
10 Growing egg. Vacuolization of the nucleolus very marked. Chromatin 
emission. X 1228. . 
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