CONTENTS 



CHAPTER PAGE 



I. The Amphibia in General and Frogs in Particular i 



II. The Habits and Natural History of the Frog . 23 



III. External Characters of the Frog 62 



IV. Preliminary Account of the Internal Stru^jUre 68 

 V. The Development of the Frog .... 81 



VI. Histology of the Frog 121 '/ 



- VII. The Digestive System and its Functions . .134 



VIII. The Vocal and Respiratory Organs . . . 165 



IX. The Skin 179 



X. The Excretory System 201 ^ 



XI. The Reproductive Organs and the Fat Bodies . 212 



XII. Internal Secretion and the Ductless Glands . 219 



—XIII. The Skeleton 229 



- XIV. The Muscular System 246 



XV. The Circulatory System 258 



■ -^XVI. The Nervous System 283 , 



XVII. The Sense Organs 321 



XVIII. Instincts and Tropisms as related to Reflex 



Action 342 



XIX. The Intelligence of the Frog . . . , 353 ^ 



INDEX 359 



IX 



