CONTENTS. 
is 
CHAPTER XIX. page 
Reproduction... 191 
CHAPTER XX. 
Development. 197 
1. Metamorphosis . 207 
2. Alternate Generation. 21 L 
3. Growth and Repair. 214 
4. Likeness and Variation. 215 
5. Homology, Analogy, and Correlation . 217 
6. Individuality . 220 
7. Relations of Number, Size, Form, and Rank. 221 
8. The Struggle for Life. 226 
PART II.—SYSTEMATIC ZOOLOGY. 
CHAPTER XXI. 
The Classification op Animals . 231 
Protozoa... 238 
Spongida. 244 
Ccelenterata. 246 
Echinodermata. 257 
Vermes. 263 
Mollusea.. . 269 
Arthropoda. . 281 
Tunicata... 305 
Vertebrata. . 306 
CHAPTER XXII. 
Systematic Arrangement of Representative Forms . 362 
CHAPTER XXIII. 
The Distribution of Animals. 371 
NOTES . 381 
THE NATURALIST’S LIBRARY.. 397 
INDEX 
399 
