viii CIVIC BIOLOGY 



CHAPTER PAGE 



XXIII. CONTROL OF BACTERIAL DISEASES 231 



XXIV. CONTROL OF ANIMAL PARASITES > . 253 



XXV. Civic PROBLEMS RELATING TO MOLLUSKS . . . . 271 



XXVL CRUSTACEA . ... . . 285 



XXVII. PROBLEMS OF FISH AND FISHING 295 



XXVIIL AMPHIBIA : SIRENS, PROTEANS, SALAMANDERS, FROGS, 



TREE FROGS, AND TOADS 313 



XXIX. REPTILES : CROCODILES, ALLIGATORS, TURTLES, TER- 

 RAPINS, TORTOISES, LIZARDS, SNAKES . . . . . 321 



XXX. PRACTICAL LAWS OF LIFE 330 



XXXI. KNOWING How TO KNOW How 346 



XXXII. PROGRESS IN DISCOVERY 355 



INDEX . 363 



