386 SYNOPSIS 



PAGE 



6. Mycetozoa. 



Like Protomyxa, but owing to the presence of nuclei the 

 relation of the individual cell-bodies to the plasmodium 

 is more clearly seen : cell wall of cellulose 5 2 



7. Saccharomyces. 



Cell-body encysted : cell-wall of cellulose : nutrition 

 saprophytic : reproduction by gemmation or by internal 

 fission : acts as an organized ferment 7 



8. Bacteria. 



Cell-body ciliated or encysted : cell-wall of cellulose : 

 nutrition saprophytic : reproduction by binary fission or 

 by spore-formation : act as organized ferments : the 

 simplest and most abundant of organisms 82 



II. UNICELLULAR ORGANISMS IN WHICH THERE is CONSIDERABLE 

 COMPLEXITY OF STRUCTURE ACCOMPANIED BY PHYSIOLOGICAL 

 DIFFERENTIATION. 



a. Complexity attained by differentiation of cell-body. 



9. Paramoecium. 



Medulla, cortex, and cuticle : trichocysts : complex con- 

 tractile vacuoles : nucleus and paranucleus : mouth, 

 gullet, and anal spot : conjugation temporary, no zygote 

 being formed, but interchange of nuclear material during 

 temporary union 106 



I o. Stylonych ia. 



Extreme differentiation or heteromorphism of cilia ... 116 



1 1 . Oxytricha. 



Fragmentation of nucleus 120 



12. Opalina. 



Multiplication of nuclei ; parasitism and its results ; 

 necessity for special means of dispersal of an internal 

 parasite 121 



13. Vorticella. 



A stationary organism : limitation of cilia to defined 

 regions : muscle-fibre in stalk : necessity for means of 

 dispersal in a fixed organism : conjugation between free- 

 swimming micro- and fixed mega-gamete : zygote indis- 

 tinguishable from a zooid of the ordinary kind .... 126 



14. Zoothamnium. 



A compound organism or colony with dimorphic (nutri- 

 tive and reproductive) zooids : begins life as a single 

 zooid 135 



