C. B. METZ 27 



view by demonstrating that specific egg water increases the motil- 

 ity of Arhacia sperm. This sperm activating action of egg water 

 has been confirmed in a number of forms inckiding Megathura 

 (Tyler, 1940a) and other molluscs (von Medem, 1945), the 

 annelid Nereis (Lillie, 1913b), and several sea urchins. However, 

 it does not appear to be a universal property of egg water for 

 Metz (1945) found no sperm activating action of starfish egg 

 water in spite of Loeb's ( 1915 ) claims to the contrary. 



The nature of the sperm activating agent in sea urchin egg 

 water has been the subject of some dispute. Loeb (1915) be- 

 lieved that this agent differed from fertilizin since egg water pre- 

 pared from fertilizin-free eggs still activated sperm and because 

 calcium ion was required for the agglutination but not the activat- 

 ing action of egg water. 



In studies that aroused much interest at one time Hartmann, 

 Kuhn, Schartau, and Wallenfels ( 1939 ) reported that crystalline 

 preparations of the substituted naphthaquinone, echinochrome, in 

 sea water solution activated the sperm of Arhacia. Echinochrome 

 occurs in the fonn of granules in eggs of the genus Arhacia. Tyler 

 (1939a) and Cornman (1941), however, were unable to confirm 

 this action of echinoclii^ome on sperm of Strongylocentrotiis ptir- 

 puratus and Arhacia punctulata respectively. Both of these inves- 

 tigators used crystalline preparations. Cornman ( 1941 ) suggested 

 that Hartmann's results may have resulted from failure to control 

 the pH of the solutions. Bielig and Dohrn (1950) found no 

 sperm activating action of echinochrome in buffered systems. It 

 would appear, then, that there is no confirmatory evidence to sup- 

 port the view that echinochrome activates sperm. 



Volatile or dialyzable sperm activating agents have been re- 

 ported from egg waters by several investigators (Clowes and 

 Bacliman, 1921; Cornman, 1941; Vasseur and Hagstrom, 1946). 

 Tyler and Fox (1939, 1940), however, found that sperm activat- 

 ing action remained with fertilizin through precipitation and 

 dialysis. Tyler (1955) concluded that the activating action of 

 egg water is associated with the fertilizin but that the fertilizin 

 may be split to yield volatile or dialyzable fractions with sperm 

 activating properties. 



