FERTILIZATION REACTION IN ECHINARACHNIUS PARMA. 2Q 



sperm. Thus, we have a sharply defined difference in behavior 

 between the Echinarachnius egg and the Arbacia egg with respect 

 to foreign sperm. 



B. Hetero-agglutination in Echinarachnius and Arbacia. 

 If fertilizin is necessary for fertilization and if it is likewise 

 specific, we should expect that where cross fertilization is pos- 

 sible in one direction only the sperm agglutination reaction- 

 would, if it occurred at all, take place in the same direction 

 The opposite appears to be the case for the Echinarachnius X 

 Arbacia cross since Echinarachnius egg-water has no effect on 

 Arbacia sperm while Arbacia egg- water has a powerful aggluti- 

 nating effect on Echinarachnius sperm. However, as shown 

 beyond this is not the effect of Arbacia sperm agglutinin but is 

 due to a separate substance, a hetero-agglutinin. 



i. Effect of Echinarachnius Egg-water on Arbacia Sperm. 



Sea-water from above Echinarachnius eggs highly charged 

 with the substance that agglutinates Echinarachnius sperm has 

 no agglutinative action on Arbacia sperm. This is true of the 

 most powerful Echinarachnius egg-water that was used.- The 

 Echinarachnius egg-water does, however, intensely activate 

 Arbacia sperm. 



Experiments were made with egg-water of both " ovary " and 

 dry eggs. 



July 2, 10:00 A.M. Eggs from four Echinarachnius strained and washed 5 

 times in 250 c.c. of sea-water. 2 c.c. of eggs and small bits of ovary. 12:00 M., 

 210 c.c. of sea-water removed and filtered. Tests with Echinarachnius sperm, at 

 1:30 P.M. and 8:30 P.M., showed great agglutinating strength. 



11:00 A.M. Eggs from Arbacia washed 5 times in 100 c.c. of sea-water at each 

 washing. 12:05 P.M., 45 c.c. of supernatant sea-water removed and filtered. 

 Tested with Arbacia sperm, showed very powerful reaction. 



3:00 P.M. Arbacia egg-water agglutinates Arbacia sperm; Echinarachnius 

 egg-water agglutinates Echinarachnius sperm, but fails to agglutinate Arbacia 

 sperm trials being made on sperm of three males. 



July 10, 10:30 A.M. I 1/2 c.c. of dry eggs of Echinarachnius in 8 1/2 c.c. of 

 sea-water. n:ooA.M. 8 c.c. of sea-water were pipetted off and filtered. (8 c.c. 

 of fresh sea-water added to the eggs.) 1 1 :05 A.M. 7 c.c. of Arbacia eggs from four 

 females put in 50 c.c. of sea-water. 



12:10 P.M. Echinarachnius secretion gives a 5-6-second reaction with its 

 sperm on 1/500 dilution; full strength, this fails to agglutinate Arbacia sperm. 

 Arbacia sperm suspensions used were 50 per cent., 20 per cent., 10 per cent, and 

 i per cent, freshly prepared in each case. Arbacia egg-water agglutinates Arbacia 

 sperm. 



