FERTILIZATION AND EGG-SECRETIONS. 65 



second lot of eggs was treated with normal egg-secretion and 

 inseminated in its presence. The results show a decrease in the 

 inactive eggs to 50 per cent. a decrease in the anomalous 

 cleavages to 14 per cent, and an increase in normal divisions to 



36 per cent. 



II. 



Our second question is, how do the exudates act? Naturally, 

 we must formulate our explanation in terms of material entities. 

 This, indeed, was done from the first, but the entity postulated 

 was little more than a symbol for the observed effects. 



These fall into two groups: the effects on spermatozoa and the 

 effects on eggs. As Lillie first found, the spermatozoa are 

 activated and exhibit a remarkable process of swarming and 

 agglutination; the eggs, as I found, upon exposure to secretion 

 develop spontaneously. Lillie attributed both phenomena to a 

 single substance -the agglutinin of his earlier papers the fer- 

 tilizin of his later writings. 



Lillie has introduced prevention as an aid to analysis, and has 

 described two natural inhibitors. In the presence of one of these, 

 the "anti-fertilizin" derived from the eggs themselves, spermato- 

 zoa do not swarm and agglutinate and eggs cannot be fertilized; 

 in the presence of the other, contained in species-true blood, 

 although the spermatozoa agglutinate, nevertheless the eggs fail 

 to develop. 



To account for these facts, Lillie made the following assump- 

 tions: The agglutinin has two bonds. One of these normally 

 combines with a sperm-borne valence. The symptom of such 

 union is the agglutination reaction. The other bond of the 

 agglutinin unites with an egg-borne valence. The symptom of 

 this union is the initiation of development. "Anti-fertilizin," 

 prevents fertilization because it binds the spermophile group of 

 the agglutinin and so renders the normal union with the sperm- 

 valence impossible. Inasmuch as the inhibitor in the blood 

 does not affect the agglutination reaction, this substance is 

 assumed to occupy the ovophile bond of the agglutinin. Apply- 

 ing the picture-language of Ehrlich, Lillie called the agglutinin an 

 "amboceptor," whose two bonds are satisfied in fertilization in 

 the suggested manner. 



