X TABLE OF CONTENTS 



Page 



Phylum lo. — Urochorda. Classes of tunicates 285 



Phylum II. — Acrania 286 



Phylum 12. — Vertcbrata: Cyclostomala. Pisces. Orders of fishes. 



Amphibia. Orders of amphibia. Reptilia. Orders of reptiles. 



Aves. Orders of birds. Mammalia. Orders of mammals . . 287 



PART III.— GENERAL PRINCIPLES 



Spontaneous generation. Continuity of the living substance. Struc- 

 ture of protoplasm. The nucleus. Chemical structure of 

 protoplasm. Function of cytoplasm and nucleus. Cell division. 

 Number of chromosomes. Nucleoli. Centrosomes. Spindle 

 fibres. Resting nucleus. Conjugation. Fertilization. Matur- 

 ation. Conjugation in protozoa. Fertilization stimulus. Cleav- 

 age. The blastula. The gastrula. The medullary plate. The 

 notochord. The mesoderm. Other types of cleavage. Origin 

 of the tissues. Indirect development. Differentiation of germ- 

 inal and somatic tissues. Division of labor and differentiation. 

 Regeneration. Mechanics of growth. Progressive and regressive 

 development. Sexual dimorphism. Polymorphism. Alterna- 

 tion of generations. Life habits depending on food. Parasitism. 

 Protozoa as parasites. Bacteria as parasites. Immunity . .'. 307 



Species. Variation. Heredity. Mendel's law. Physical basis of 

 heredity. Number of species. Origin of species. The Taxo- 

 nomic Series. The Phylogenetic Series. The Ontogenetic Series. 

 The struggle for existence. Natural Selection. Animals and 

 plants under domestication. Geographical distribution. 382 



Adaptations: Pollination. Care of young. Sexual dimorphism. 

 Sexual selection. Welfare of the individual and of the species. 

 Animal coloration. Protective resemblance. Feigning. Mim- 

 icry. Color changes. Luminescence. Electrical organs. In- 

 stinct. Intelligence 407 



Index 439 



