EFFECT OF X-RADIATION ON FERTILIZIN. I47 



probable that fertilizin is simply one example of a group of sub- 

 stances which may be the object of such action (but an example 

 which may be studied). It is to be noted that these experiments 

 render untenable the conclusion of the Hertwigs, that chromatin 

 is the chief and perhaps exclusive seat of the effects of radiation 

 upon eggs. Fertilizin is a substance doubtless without mor- 

 phological representation in the structure of the egg; yet it may 

 suffer considerable modification from x-ray treatment. 



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 Euler, H. 



'12 General Chemistry of the Enzymes. New York. WileJ^ 

 Glaser, Otto 



'13 On Inducing Development in the Sea Urchin (Arbacia punctulata) 



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Science, N. S., 38, p. 446. 

 '14a A Qualitative Analysis of the Egg-Secretions and Extracts of Arbacia and 



Asterias. Biol. Bltll., XXVI. 

 '14b On Auto-Parthenogenesis in Arbacia and Asterias. Biol. Bull., XXVI. 

 Lillie, F. R. 



'13a Studies of Fertilization. V. The Behavior of Spermatozoa of Nereis and 



Arbacia with Special Reference to Egg Extractives. Jour. Exp. Zool., 14. 

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Jour. Exp. Zool., 16. 

 Richards, A. 



'14 The Effect of X-Rays on Certain Enzymes. Amer. Jour. Physiol., 35. 



