xii PROBLEMS OF FERTILIZATION 



PAGE 



Fig. 14. Reaction of a Sperm Suspension of Nereis 

 TO A Drop of i Per Cent C02 Sea- 

 Water 105 



Fig. 15. Diagram of the Reaction of Spermatozoa of 

 Nereis to a Drop of i Per Cent C02 in Sea- 

 Water 106 



Fig. 16. Curve of Fertilizing Power of Perfectly 



Fresh Sperm Suspensions of Arhacia . . 135 



Fig. 17. Curve of Fertilizing Power of Sperm Sus- 

 pensions OF Arhacia About 20 Minutes Old 137 



Fig. 18. Imbibition of Water by Arhacia Eggs in 



Diluted Sea-Water 150 



Fig. 19. Curve of Fertilization Superimposed upon 



Butyric Acid Treatment in ylrftac/a . . 168 





