CHAPTER YIL 



THE PROCESSES OF EVOLUTION AND IMPREGNATION. 



Development of the Many-celled from the -One-celled Organism. Tho Cell- 

 hermit and the Cell-state. The Principles of the Formation of the 

 State. The Differentiation of the Individuals as the Standard of Measure- 

 ment for the Grade of the State. Parallel between the Processes of 

 Individual and of Race Development. The Functions of Evolution. 

 Growth. Inorganic and Organic Growth. Simple and Complex Growth. 

 Nourishment and Change of Substance. Adaptation and Modification. 

 Reproduction. Asexual and Sexual Reproduction. Heredity. Divi- 

 sion of Labour, or Differentiation. Atavism, or Reversion. Coalescence. 

 The Functions of Evolution as yet very little studied by Physiology, 

 and hence the Evolutionary Process has often been misjudged. The 

 Evolution of Consciousness, and the Limits to the Knowledge of Nature. 

 Fitful and Gradual Evolution. Fertilization. Sexual Generation. 

 The Egg-cell and the Sperm-cell. Theory of the Sperm-animals. 

 Sperm-cells a form of Whip-cell. Union of the Male Sperm-cell with 

 The. Female Egg-cell. The Product of this is the Parent-cell, or 

 Cytnla. Nature of the Process of Fertilization. Relation of the Kernel 

 (Nucleus) to this Process. Disappearance of the Germ-vesicle. Mone- 

 rula. Reversion to the Monera-form. The Cytula. 



" If the man of science chose to follow the example of historians and 

 pulpit-orators, and to obscure strange and peculiar phenomena by employing 

 a hollow pomp of big and sounding words, this would be his opportunity ; 

 for we have approached one of the greatest of the mysteries which surround 

 the problem of animated nature and distinguish it above all other problems 

 of science. To discover the relations of man and woman to the egg-cell 

 would be almost equivalent to solving all those mysteries. The origin and 

 development of the egg-cell in the body of the mother, the transfer to it 



