Page:Popular Science Monthly Volume 67.djvu/115

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which must have been condensed in the ovary of Eve, arrived at the amazing result of two hundred millions.

Work of Wolff.—Wolff, as a young man of 26 years, set himself against this grotesque doctrine of preformation and encasement, in his 'Theoria Generationis,' published in 1759. This consists of three parts: One devoted to the development of plants, one to the development of animals and one to theoretical considerations. He contended that the organs of animals make their appearance gradually, and that he could actually follow their successive stages of formation.

The figures in it illustrating the develomentdevelopment [sic] of the chick, some of which are shown in Fig. 6, are not, on the whole, so good as Malpighi's. Wolff gives in all seventeen figures, while Malpighi published