CHAPTER XVII. 



SYNTHETIC HETEROGENESIS. 



The 'Pellicle.' Biocrasis. Observations of Pineau and Pouchet. 

 Author's Observations. Formation of Embryonal Areas. Origin 

 of Amoebae and of Fungus-spores. Mode of Origin of Embryonal 

 Areas. Direct origin of Monads and Fungi from same Elements. 

 Development of Flagellum. Indirect Origin of Monads. Their 

 Transformation into Amoebae. Encystment. Death of others by 

 Analytic Heterogenesis. Origin of other Amoebae by Archebiosis. 

 Subsequently break up into Fungus-spores. Similar Fungus-spores 

 arising by Archebiosis. Their Germination. Mutual interchange- 

 ability between Monads, Amoebae, and Fungus-spores. Further 

 proof. Fungus-spores, or Monads and Amoebae, producible at will 

 from Embryonal Areas. Embryos of Unknown Organism. Origin 

 of Enchelys seen by Pineau. Origin of Paramecium described by 

 Pouchet. Confirmation by Joly and Musset. Essential Conditions. 

 Author's Observations on Origin of Paramecia. Fission of Em- 

 bryos. Their Minute Structure. Great Simplicity. Subsequent 

 Modifications. Origin of Vorticellse. Pineau's Observations. 



Theoretical objections. These fostered by Novelty of the Facts. Similar 

 Difficulties concerning Formation of Crystals and Development of 

 Higher Organisms. Diversity of ' Spontaneous ' Products. This 

 natural and long recognized. Infusorial ' Species ' Convertible. 

 Mutability an Essential Characteristic. Facts recorded easily Veri- 

 fiable. Synthetic Heterogenesis comparable with the Synthesis 

 occurring in Archebiosis. 



THE mode of formation of the c primordial mucus ' 

 of Burdach the c proligerous pellicle' of Pouchet 

 has been already described ; but it now remains for us 



