XIV CONTENTS. 



CHAPTER XII. 



PAGE 



Theory of Fertilisation . . . . . 157-168 



§ I. Old theories — 



{a) Ovists, {/?) animalculists, (<:) the " aura 

 seDiinalisy 

 § 2. Modern morphological theories — 



(a.) Nuclei all - important. Hertwig, Stras- 



burger, &c. 

 {b.) Cell-substance also important. Nussbaum, 

 Boveri, &c. 

 § 3. Modern physiological theories — 



Sachs, De Bary, Marshall Ward, (S:c. 

 Cienkowski and Rolph, 

 Weismann's view. 



Critique and statement of present theory. 

 § 4. Use of fertilisation to the species — 

 (a.) Rejuvenescence — 



Van Beneden and Blltschli. 

 Galton and Hensen. 

 Weismann's critique. 

 '{b.) The observations of Maupas. 

 {c.) A source of variation. Brooks and Weismann. 



CHAPTER XIII. 



Degenerate Sexual Reproduction or Parthenogenesis 169-187 

 §1. History of discovery. 

 § 2. Degrees of parthenogenesis — 



Artificial, pathological, occasional, partial, sea- 

 sonal, total. 

 § 3. Occurrence in animals — 



Rotifers, crustaceans, insects. 

 § 4. Occurrence in plants — 



Phanerogams and fungi. 

 § 5. The offspring of parthenogenesis. 

 § 6. Effects on the species. 

 § 7. Peculiarities of parthenogenetic ova- — 



Weismann's discovery. 

 § 8. Theory of parthenogenesis — 



Minot and Balfour. 



Rol]5h and Strasburgcr. 



Weismann. 



The present. 

 § 9. Origin of parthenogenesis. 

 I o. Case of bees. 



CHAPTER XIV. 

 Asexual Reproduction . . . . . 188-199 



§ I. Artificial division. 

 § 2. Regeneration. 



§ 3. Degrees of asexual reproduction. 

 § 4. Asexual reproduction in plants and animals. 



