THE CHILD 



The question is often asked in what way the reproductive 

 organs of man differ from those of the animal. Fundamentally 

 there is no difference, but there are naturally many variations 

 of detail, such as size and position of organs, number of 

 young, length of the period of gestation, etc. Physically 

 speaking, the relation of man to the higher animals, especially 

 the apes, is affirmed in a thousand ways. Sexual reproduc- 

 tion is part and parcel of the vertebrate organization. It is 

 so closely identified with the animal economy as to exhibit 

 little change from the earliest times. Thus, the ovaries of 

 most fish produce hundreds of thousands of eggs during the 

 life of the fish. Likewise, each ovary of a three-year-old 

 female child has fully 400,000 eggs within it. Since at most 

 only a few hundred eggs are discharged, nature makes an 

 effort to economize by reducing the great number to about 

 36,000 by the time the child is eight years of age. The sperms 

 of the human male are produced by the hundred million. 

 Though many are still needed, such vast numbers probably 

 reflect a time when they were shed in the water and great 

 numbers were required to insure fertilization of the eggs. 



Human Sperm Cells and How They are Produced 



There are several typical methods of reproduction in the 

 living world: (1) that of direct division, as in many low orders 

 of plants and animals in which a single cell, the parent, divides 

 to form daughter cells; (2) that of spore formation, as in 

 ferns and fungi ; (3) that of budding, in which a single parent 

 gives rise to progeny by pushing out a bud from the parent 

 body, the new individual remaining in connection with the 

 parent body or detaching itself; (4) that of bulb formation; 

 (5) that of sexual generation, in which specialized cells are 

 regularly set apart to perform the function of producing the 

 new individual. Most plants and animals have come from 

 ancestors that early chose this last method of reproduction. 

 For all vertebrates this method is universally true. When 



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