II] CLASSIFICATION 47 



Order 3. Dinoflagellata. 



Forms with a thick cellulose cuticle and with transverse 

 and longitudinal grooves each containing a flagelluin. 



Order 4. Choanoflagellata. 



Forms with a protoplasmic collar surrounding the base of 

 the flagellum. 



Order 5. Lissoflagellata. 



Forms with well-marked cuticle and myonemes but no 

 collar, skeleton, or groove. Lissoflagellata parasitic in the 

 blood are termed Haematoflagellata. 



Class III. CILIATA. 



Protozoa bearing numerous cilia, at least When young. Vege- 

 tative and special sexual nuclei develop. 



Order 1. Holotricha. 



Cilia all over body, all same size. 



Ex. Paramecium. 

 Order 2. Peritricha. 



A wreath of cilia round one end. 



Ex. Vorticella. 

 Order 3. Suctoria. 



Cilia replaced in adult condition by suctorial tentacles. 

 Ex. Acineta. 



Class IV. SPOROZOA. 



Protozoa, with or without stiff cuticle and myonemes, in which 

 spores are formed, the contents of which break up into several 

 amoeboid young. All when young are parasites within the proto- 

 plasm of their hosts. 



Sub-class I. NEOSPORIDIA. 



Fission and the formation of spores occur at the same time in 

 different parts of the body. 



