Page:Popular Science Monthly Volume 79.djvu/582

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THE POPULAR SCIENCE MONTHLY

case of Paramecium, it will be seen that the conditions are entirely different from those which accompany conjugation in the majority of

Fig. 12.After Lèger

Protozoa. In the latter fertilization is accomplished by the formation and fusion of gametes or minute simulacra of the adult cells, some being differentiated into microgametes and macrogametes, or male and female.