CONTENTS OF VOL. I. XXvii 



Page. 



2. Oviparous Animals. Male organs. Female organs. 

 Egg. Impregnation. Hatching. Ovoviviparous 

 Animals. . . 415 



3. Androgynous Animals. Organs. Sexual union re- 



quisite in some. Hermaphroditism complete in 

 others. 423 



4. Gemmiparous Animals, Spontaneous division. . 424 



5. Hybridous Animals. Prevented by the selective 

 attribute of the procreative instinct. Circumstances 

 under which they are produced. They are barren. 428 



