ILLUSTRATIONS 



Figure Page 



1. Portion of Florida west coast in which experimental control 



of red tide was attempted during September and October of 



1957 41 



2. Areas dusted with copper sulfate showing the dates and the 



tonnages used (see table 1) 42 



3. Survey of red tide occurrence on September 26, 1957 .... 43 



4. Survey of red tide occurrence on September 27, 1957 .... 44 



5. Survey of red tide occurrence on September 28, 1957 .... 45 



6. Survey of red tide occurrence on September 29, 1957 .... 46 



7. Survey of red tide occurrence on October 2, 1957 47 



8. Survey of red tide occurrence on October 3, 1957 48 



9. Survey of red tide occurrence on October 4, 1957 49 



10. Survey of red tide occurrence on October 5, 1957 50 



11. Survey of red tide occurrence on October 6, 1957 51 



12. Survey of red tide occurrence on October 7, 1957 52 



13. Survey of red tide occurrence on October 8, 1957 53 



14. Numbers of red tide organisms per liter off Blind Pass ... 54 



15. Numbers of red tide organisms per liter off John's Pass . . 54 



16. Numbers of red tide organisms per liter off Madeira Beach . 55 



17. Numbers of red tide organisms per liter off Indian Rocks 



Beach 55 



18. Numbers of red tide organisms per liter off Little Pass • • 56 



19. Microgram atoms of copper per liter off John's Pass and 



number of red tide organisms per liter. Empirical curve 



shows that number of organisms was reduced at higher 



levels of copper 56 



20. Surface water samples from off Blind Pass showing the num- 



ber of red tide organisms and copper concentrations per 



liter. The before and after dusting points for the G. 



breve curve on September 29 show the swift destruction of 



G. breve when the copper concentration rose 57 



