396 OTTO GLASER. 



However the failure of the fertilizin with which the eggs were 

 treated and for which they are permeable, to offset the effects of 

 washing, remains to be accounted for. 



2. . The Prevention of Auto-parthenogenesis by Means of a Group 

 Split from the Sperm. Lillie has made the apparently justifiable 

 assumption that fertilizin bound by sperm is activated, i. e., has 

 a greater chemical affinity for the substances with which it unites 

 in the egg than the unbound fertilizin. If this is true, it occurred 

 to me that the use of sperm, in conjunction with the secretion 

 might give better auto-parthenogenetic results than had been 

 obtained by the use of the secretion alone, either with or without 

 the hypertonic after-treatment. Naturally only dead or seriously 

 injured sperm are available for this experiment, and with the latter 

 one could not be sure to exclude a certain and misleading number 

 of real fertilizations which would then be mistaken for very fine 

 cases of parthenogenesis. Since the power of the fertilizin to 

 produce the agglutination reaction and to play a part in normal 

 fertilization is not destroyed by brief boiling, it seemed possible 

 that the complementary chemical groups in the sperm might also 

 survive boiling without being destroyed or so altered as to be 

 incapable of taking some part at least in the reactions between 

 egg and fertilizin. 



However, instead of furthering auto-parthenogenesis, exactly 

 the opposite effect was found, for the boiled sperm absolutely 

 prevented the process, as shown by the following experiment: 



i volume of eggs-f-i volume of secretion 1 +2 volumes boiled 

 sperm infusion 10.40 A.M. to 2.50 P.M. Four hours later 

 little if any effect visible; a few cell-masses were noted, but 

 nothing that in any way suggested auto-parthenogenesis. 

 At 2.58 P.M. the mixture was diluted with an excess of sea- 

 water. At 6 P.M. no effect was noticeable; by 10 A.M. the 

 next day, the eggs had undergone a granular decomposition. 



Experiment repeated carefully controlled. Result identical. 

 In the control however auto-parthenogenesis occurred and 

 on the following morning 12 very fine larvae were seen in ad- 

 dition to the usual number of delayed cleavages and micro- 

 blastulse. 



1 Unfortunately the egg-secretion in these tests was more dilute than usual, but 

 the effect noted is not interpretable on this basis since parthenogenesis occurs at 

 greater dilutions. The sequel to these experiments further emphasizes the inter- 

 pretation given here. 



