ON EGGS OF MARINE ANIMALS 53 



. 1922. Initiation of development in the egg of Arbacia. 



I. Effect of hypertonic sea-water in producing membrane separa- 

 tion, cleavage and top-swimming plutei. Biol. Bull., Vol. 43. 



LiLLiE, R. S. 1908. Momentary elevation of temperature as a 

 means of producing artificial parthenogenesis in starfish eggs and 

 the conditions of its action. Journ. Exp. Zool., Vol. 5. 



. 1916. Mass action in the activation of unfertilized starfish 



eggs by butyric acid. Journ. Biol. Chem., Vol. 24. 



LoEB, J. 1913. Artificial parthenogenesis and fertilization. Univ. 

 Chicago Press, Chicago. 



