CONTENTS. 



CHAPTER. . PAGE 



1 INTRODUCTORY 1 



' 2 Ouu RELATIONS 2 



3 EMBRYOLOGY 9 



4 COMPARATIVE DEVELOPMENT '. 27 



5 RUDIMENTS 46 



6 TABULAR REVIEW 56 



7 TESTIMONY OP GEOLOGY <>5 



8 Eozoio AGE 70 



9 SILURIAN, AGE or MOLLUSKS , 73 



10 DEVONIAN, AGE OF FISHES 80 



11 CARBONIFEROUS, COAL AGE 82 



12 MESOZOIC, REPTILIAN AGE 85 



13 TERTIARY, AGE OF MAMMALS 91 



14 QUARTERNARY OR POST TERTIARY PERIOD 96 



15 THE GEOLOGICAL LESSON 97 



16 NATURAL SELECTION OF SPECIES 105 



17 SEXUAL AND ARTIFICIAL SELECTION 115 



18 PERIODICITY 121 



19 EFFECT OF TEMPERATURE 125 



20 VARIOUS MODIFYING AGENCIES 131 



21 BILATERALISM 145 



22 OSSEOUS SYSTEM 156 



23 RESPIRATORY SYSTEM 171 



24 CHLOROPHYL 176 



25 PARASITISM AND SOCIAL RECIPROCITY 183 



26 FUNGI 200 



27 ORGANIC FERMENTS 213 



28 SOLUBLE FERMENTS, DIGESTION 225 



29 REPRODUCTION OF VEGETAL CELLS 234 



30 CELLULAR PLANTS, INFUSORIA AND THEIR TRANSMUTATIONS. . 243 



31 ZYMOTIC AND GERM DISEASES 254 



32 DIFFERENTIATION 268 



33 ORIGIN OF SEX 294 



34 HABIT 315 



35 ENERGY 318 



36 ELECTRICITY 324 



37 CRYSTALLIZATION 347 



38 POLARITY IN ORGANIC ELEMENTS 360 



39 SOUND 372 



40 HEAT AND LIGHT GENERAL THEORY OF RADIATION 381 



41 EFFECT OF BODIES ON LIGHT AND HEAT 387 



42 EFFECTS OF HEAT AND LIGHT ON INORGANIC BODIES 409 



43 EFFECTS OF LIGHT AND HEAT ON ORGANISMS, 416 



44 CHROMATIC FUNCTION 419 



