Contents 



1. Introduction 1 



2. Protoplasm and Cellular 

 Organization 14 



3. Phylum Protozoa. One- 

 Ceiled Animals 30 



4. Phylum Protozoa. Flagel- 

 lates 42 



5. Phylum Protozoa. One- 

 Celled Parasites 50 



6. Phylum Protozoa. Ciliates 54 



7. Relations of Protozoa to 



Man 67 



8. Introduction to the Meta- 



zoa 78 



9. Phylum Porifera. Simple 

 Multicellular Animals 92 



10. Phylum Coelenterata 

 (Cnidaria). Simple Tissue 

 Animals 102 



11. Phylum Ctenophora. 



Comb Jellies 130 



12. Phylum Platyhelminthes. 

 Simple Organ-System 

 Animals 133 



13. Phylum Nemathelmin- 



thes, Phylum Nemato- 

 morpha, and Phylum 

 Acanthocephala. Round- 

 worms 1 49 



14. Miscellaneous Minor Phyla 163 



