duce, in the other as the instinct to seek a mate 

 and the will to hunt a meal. The obvious corollary 

 of this, of course, is that these laws have prevailed 

 from the time of the beginning of the first cell 

 until the present day. 



It is patent, however, that these laws are not of 

 equal force as regards the individual organism. 

 The law pertaining to reproduction is paramount 

 — nothing in the lives of higher animals is more 

 purposeful than the pursuit of love, nothing 

 among lower creatures is fraught with greater ur- 

 gency than the demands of this most potent of in- 

 stincts or what passes for its pristine equivalent. 

 In a word, the affairs of the stomach give prece- 

 dence to the affairs of the heart. 



From these considerations, it may at first sight 

 appear as passing from the sublime to the ridicu- 

 lous to speak of sex-appeal in a worm. Neverthe- 

 less, the fact cannot be disguised that it was at 

 least something partaking of this element that led 

 some simple-structured creature to grope its way 

 out of the labyrinth in which so many forms were 

 lost, and to arrive at the estate of man. And that 

 this lowly creature was the early flatworm is not 

 beyond belief. Thus conceived, it was a fixed form. 



[182] 



