14 A. J. GOLDFARB. 



in the eggs of different females. They ascribed the primary 

 variation to a difference in the amount of enzyme present in the 

 different eggs of the same parentage. 



In earlier studies, I showed that the ripe eggs from different 

 freshly collected females varied far beyond Loeb's individual or 

 primary variation. I determined the exact range of variability of 

 the freshly removed eggs, not merely in one but in several morphologic 

 and physiologic entities, and for three species of sea urchin. I 

 showed moreover that these variations were measurable and corrobora- 

 tive indices of differences in the vitality or physiologic condition of 

 the different lots of eggs. And hence it was possible not only to 

 ascertain with exactitude the condition of the eggs but to sort them out 

 according to their physiologic condition. 



This unusual diversity in freshly liberated eggs of different 

 females is due, firstly to the original or primary variability of 

 Loeb and Chamberlain already referred to; secondly, to injurious 

 changes that take place within the body of the female before 

 liberation, and even as early as the maturation of the egg. 

 For as soon as maturation is completed the eggs are susceptible 

 to injurious agencies in the body fluid of the mother, particularly 

 changes in ionic concentration and oxygen content. Whether 

 these be the sole injurious agents or whether accumulated toxic 

 (metabolic) substances also contribute, I cannot say. In any 

 event, the equilibrium is upset and the cycle of physiologic 

 deteriorative changes which begins with maturation, proceeds at 

 varying rates depending upon the length of time the eggs are held 

 within the body, and the nature of the body fluids. 



Since the eggs of different females may mature at different times, 

 and the eggs of a given female mature at different intervals, and since 

 the body fluids either cause or permit deleterious changes to take 

 place, and finally since the time between maturation and liberation 

 may vary very widely in different females, it is not surprising then 

 that such marked differences obtained in the different lots of eggs. 

 These marked variations occurred in the two southern species 

 probably throughout the breeding season; in the northern 

 species the variation was less marked during the height of the 

 breeding season. 



Hence to assume that ripe eggs of different females, or that 



