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THE POPULAR SCIENCE MONTHLY.
in which the egg undergoes a part of its development within the body of the mother, as it is of oviparous forms in which the eggs are laid before development begins.
The fertilized egg of a star-fish, or frog, or man is not a different individual from the adults of these forms, rather it is a star-fish, a frog, or a human being in the one-celled stage, and thereafter this new being
Figs. 6-9. Successive Stages in the Maturation and Fertilization of the entrance cone (EC) and sperm nucleus (♁N) into the egg. Fig. 6 shows the first maformed by this division; Fig. 8, the second maturation spindle (2d Mat. Sp.) and the in the first cleavage spindle (1st CI. Sp.). (From F. R. Lillie.)
