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PROTOZOOLOGY 



permanently in the ciliates and vary in size and distribution among 

 different species. Just as flagellates show various types of move- 

 ments, so do the ciliates, though nearly all free-swimming forms 

 swim in a spiral path (Bullington, 1925, 1930). Individual cilium on a 



Fig. 48. Diagrams illustrating flagellar movements of Monas sp. 

 (Krijgsman). a-g, rapid forward movement (a, b, optical image of the 

 movement in front and side view; c, preparatory and d, e, effective stroke; 

 f, preparatory and g, effective stroke); h-j, moderate forward movement 

 (h, optical image; i, preparatory and j, effective stroke); k-o, undulatory 

 movement of the flagellum in backward movement; p, lateral movement; 

 q, turning movement. 



