Note 238-1 — Chapter I

Thus, for instance, the sturgeon can, according to Leuckart, produce 3,000,000 eggs in a year. According to Burdach, the posterity of a pair of rabbits may be over 1,000,000 in four years; and that of a plant-louse, according to Bonnet, over a 1,000,000,000 in a few weeks. The prolificacy of a species of animals is wont to be greater in proportion as the structure-material (Bildungsmaterial) saved within a given time during the course of individual life, is greater, and as material wants during the embryonic period are limited; also (teleologically), in proportion as to the danger the individual is exposed to. Compare Leuckart in R. Wagner's physiolog. Wörterbuch,[TN 62] Art. Zeugung. Teleologically,[TN 63] Bastiat says: cette surabondance parait calculée partout en raison inverse de la sensibilité, de l'intelligence et de la force avec laquelle chaque espèce résiste à la déstruction. (Harmonies, ch. 16.)