Prin. of Phys., p. 907.
Should it be objected that in the higher plants the sperm-cell and germ-cell differ, though no distinct co-ordinating system exists, it is replied that there is co-ordination of actions, though of a feeble kind, and that there must be some agency by which this is carried on.
It is a significant fact that amongst the diœcious invertebrata, where the nutritive system greatly exceeds the other systems in development, the female is commonly the largest, and often greatly so. In some of the Rotifera the male has no nutritive system at all. See Prin. of Phys., p. 954.
Prin. of Phys., p. 908.
"Parthenogenesis," pp. 66, 67.