Page:Popular Science Monthly Volume 78.djvu/545

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MEASUREMENT OF NATURAL SELECTION

complex phases and devoted ourselves temporarily to the morphological and physiological problems upon which they rest.

While testing out this idea in studies of the relationship between structural characteristics and fertility in various fruits, certain inconsistencies in results were found which could be most easily explained by the assumption that there is a selective elimination in which ovaries

PSM V78 D545 Comparisons of matured fruits with fallen ovaries of staphylea.png

Fig. 5. Comparison of Matured Fruits with Fallen Ovaries for Twenty-eight individual Shrubs of Staphylea. Differences expressed In percentages of the mean of the eliminated series. Solid dots and broken lines = mean number of ovules; circles and firm lines = radial asymmetry.

of certain types are extensively weeded out Direct investigation proved the correctness of this assumption. The results will be set forth very briefly.[1]

In the selective elimination which occurs during the development of the ovary of the American bladder nut, Staphylea, into a fruit, the

  1. ↑ Those who care for a detailed account may find it in three papers: (a) "Is there a Selective Elimination in the Fruiting of the Leguminosæ?" Amer. Nat., Vol. XLIII., pp. 556-559, 1909; (b) "On the Selective Elimination during the Development of the Fruits of Staphylea," Biometrika, Vol. VII., pp. 452-504, 1910; (c) "On the Selective Elimination of Organs," Science, n. s., Vol. XXXII., pp. 519-528, 1910.