CONTENTS xiii 



XVI. The Protozoa in Connection with Morphogenetic 

 Problems By Francis M. Summers, College of the 

 City of New York 772 



Physiological regeneration — Some of the factors in re- 

 generation — External environment — Cyclical variations 

 — Racial variations — Degree of injury and reorganiza- 

 tion — The size factor — The nuclei in regeneration — 

 Behavior of fragments: grafting and reincorporation — 

 Regeneration and division — Polarity changes and proto- 

 plasmic streaming — Physiological gradients — Regenera- 

 tion in colonial forms — Literature cited 



XVII. Certain Aspects of Pathogenicity of Protozoa By 



Elery R. Becker, lotva State College 818 



Problems of virulence and pathogenicity — Amoebic 

 dysentery and bacterial complications — Malaria: Plas- 

 modium vivax — Variability in strains and in host re- 

 sponse — Coccidiosis in poultry — Nutrition and resistance 

 - — Conclusions — Literature cited 



XVIII. The Immunology of the Parasitic Protozoa By Wil- 

 liam H. Taliaferro, University of Chicago . . . 830 



The physical bases of immunity — The cells involved in 

 immunity — Antibodies and antigens involved in immu- 

 nity — The cellular and humoral aspects of immunity — 

 Role of immune processes in the development of proto- 

 zoan infections — General methods — Malaria — Leishma- 

 niasis — Nonlethal infection with the Trypanosoma lewisi 

 group of trypanosomes — Continuous fatal trypanosomi- 

 asis in the mouse and sometimes in the rat — Intermittent 

 fatal trypanosomiasis in various laboratory animals — 

 Practical applications of immune reactions — Artificial 

 immunization — Immunological reactions used in diagno- 

 sis — Immunological reactions in relation to classifica- 

 tion — Literature cited 



XIX. Relationships between Certain Protozoa and Other 

 Animals By Harold Kirby, Jr., University of Cali- 

 fornia, Berkeley 890 



Accidental and facultative parasitism — Systematically 

 related free-living and symbiotic Protozoa — Mastigo- 



