THE rROBLEM OF ACTR'ATION 239 



the action of the secretion in this ])henomenon is spe- 

 cific, but it obviously deserves attention. This dual 

 action of the egg secretion (fertiHzin) is due in Miss 

 Woodward's opinion to two distinct substances, which 

 may be obtained separately by appropriate chemical 

 treatment. The one of these is a sperm agglutinin, 

 the other is a parthenogenetic agent. The latter has 

 fat-dissolving properties, and is assumed to be a lipase, 

 for which the name ''lipolysin" was adopted. It has 

 no agglutinating action on the sperm but is a very 

 efficient parthenogenetic agent. 



Miss Woodward then proposes a theory of activa- 

 tion in the following terms: ''The resting egg contains 

 enzymes which control metabolism, unsaturated fatty 

 acid which inhibits enzyme action, and lipolysin, which 

 reacts with the unsaturated fatty acid to make it 

 innocuous." Activation is then caused by any method 

 that increases the ratio of activating enzymes to fatty 

 acid, such as increase of lipolysin, which destroys 

 the fatty acid, or the action of fat solvents, which 

 produce the same eftect directly. It is difticult to 

 see how the spermatozoon can act in any such sense. 

 The theory does not bring together fertilization and 

 parthenogenesis. The role of the sperm-agglutinating 

 component of the egg secretion is also left out of 

 account. 



This author thus agrees with the writer with refer- 

 ence to the necessity of fertilizin and with reference to 

 its dual capacity, agglutinating the sperm and activa- 

 ting the egg. She believes, however, that two separate 

 substances, not merely two separate side chains of 

 one substance, as the writer supposed, are concerned 



