The President's Address. By the Bev. W. H. Ballinger. 195 



occurs — the divided organisms are always normal. It is, at least so 

 far as my observation has extended, only in the forms arising from 

 spore that there is any tendency to vary. 



EXPLANATION OF PLATES. 



Plate IV. 



Figs. 1-4 show the general form of the organism with its six flagella, and the 

 attitudes assumed in ordinary movement. 



Figs. 5-9 illustrate the special movement of the organism when engaged in 

 large numbers in battering minute quantities of decomposing matter, as a, fig. 9. 

 The arrows indicate the dii-ection of movement with the condition of the flagella. 

 Figs. 5-8 and 11 are illustrations of the appearance of the flagella when the 

 various stages of the battering are watched. 



Fig. 10. — Attitude of the organism before fission. 



Fig, 12. — The final stage of fission before actual breaking into two. 



Plate V. 



Fig. 1. — Appearance of the form when in ordinary motion. 



Figs. 2-8. — Various stages of the act of fission. 



Figs. 9, 10. — Two forms separated by fission — the result of the division of the 

 organism in the condition seen in fig. 8. 



Fig. 11. — A drawing of the organism as it appears when seen in the best con- 

 ditions for observation in the act of " battering." 



Figs. 12, 13. — Diagrammatic view of what is in all probability the arrange- 

 ment of the flagella in the state of motion shown in fig. 9, plate IV. 



Figs. 14-24. — Various stages in the genetic fusion of two forms issuing in 

 spores (fig. 16) and the development of young forms (figs. 17-24). 



Plate VI. 

 Various modes of fission in difierent forms of the monads already worked out. 



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