x PRIMARY FACTORS OF ORGANIC EVOLUTION. 



PAGE 



h. Phylogeny of the Horse 146 



i. The Phylogeny of Man 150 



3. The Law of the Unspecialized . 172 



CHAPTER III. PARALLELISM. 



Preliminary 175 



1. Parallelism in the Brachiopoda . 176 



2. Parallelism in the Cephalopoda . . 182 



3. Parallelism in the Vertebrata .... . 192 



4. Inexact Parallelism or Caenogeny . 200 



5. Objections to the Doctrine of Parallelism ... 205 



CHAPTER IV. CATAGENESIS. 211 



PART II. THE CAUSES OF VARIATION 



PRELIMINARY . . 225 



CHAPTER V. PHYSIOGENESIS. 



Preliminary . 227 



a. Relation of Size of Mollusca to Environment . . 229 



b. The Conversion of Artemia into Branchinecta . 229 



c. Production of Colors in Lepidopterous Pupae . . 230 



d. Effect of Light on the Colors of Flatfishes . . 238 



e. Effect of Feeding on Color in Birds 238 



f. Blindness in Cave Animals 241 



CHAPTER VI. KINETOGENESIS. 



Preliminary . 246 



1. Kinetogenesis of Muscular Structure . . ... 249 



2. Kinetogenesis in Mollusca 255 



a. Origin of the Plaits in the Columella of the Gas- 



teropoda 255 



b. Mechanical Origin of Characters in the Lamelli- 



branchiata 261 



c. Mechanical Origin of the Impressed Zone in 



Cephalopoda 268 



3. Kinetogenesis in Vermes and Arthropoda 268 



4. Kinetogenesis in Vertebrata 275 



i. Kinetogenesis of Osseous Tissue 275 



a. Abnormal Articulations 275 



