70 The Biochemistry of Semen 



but have acquired even more prominence and a wider significance in 

 recent times, chiefly as the outcome of investigations by the schools 

 of Hartmann in Germany, Runnstrom in Sweden, and Tyler in the 

 United States. So far, research on these substances has been Umited 

 largely to invertebrates; it has been thoroughly reviewed by Tyler 

 (1948), Bielig and von Medem (1949), Runnstrom (1949, 1951), 

 Brachet (1950) and Rothschild (1951^, b) and will therefore be 

 mentioned here only briefly. 



The fundamental observations on sperm-egg interacting substances 

 were made by Frank Lillie who discovered that the so-called 'egg- 

 water', that is sea-water with which sea-urchin eggs have remained in 

 contact for a while, is enriched with some substances derived from 

 the eggs, and capable of inducing the agglutination of homologous 

 spermatozoa. Lillie was convinced that the sperm-agglutinating 

 agent plays a significant role in fertilization and called it 'fertilizin'. 

 Another effect produced by egg-water, which he noted in certain 

 species of marine animals, was an increase in the motility of sperma- 

 tozoa. This phenomenon he also ascribed to 'fertilizin'; the sub- 

 stance in the sperm, with which fertilizin was believed to combine, 

 was named 'antifertilizin'. 



The sperm-egg interacting substances, mostly studied in sea- 

 urchins, are sometimes referred to as 'gamones'; those derived from 

 eggs being called 'gynogamones', as opposed to 'androgamones' in 

 sperm. 



Gynogamone I is the name given to the agent responsible for 

 the activating influence of egg- water on spermatozoa. Hartmann, 

 Schartau, Kuhn and Wallenfels (1939) thought that in the case of 

 Arbacia pustulosa the sperm-activating substance is chemically re- 

 lated to echinochrome, the pigment discovered in 1885 by MacMunn. 

 They found that pure echinochrome A (2-ethyl-3 : 5 : 6 : 7 : 8-penta- 

 hydroxynaphtoquinone) isolated from ripe eggs oi Arbacia pustulosa, 

 exerts a stimulating effect on the movements of sea-urchin sperm, 

 even in a 1 : 2,500,000,000 dilution. This claim, however, has been 

 seriously challenged by Tyler (1939) and Cornman (1940, 1941). 



At this point it may be relevant to recall two observations, one 

 by Clowes and Bachman (1921^, b) who noted that a sperm- 

 stimulating agent can be separated from egg-water by distilla- 

 tion, and the other a finding made by Carter (1931) that the 



