34 THE WHENCE AND THE WHITHEB OF MAN 



larger and stronger descendants. We have here evi- 

 dently a process corresponding to the fertilization of 

 the egg in higher animals ; yet there is no egg, sperm- 

 atozoon, or sex. 



It is a little mass of protoplasm containing a nucleus, 

 and corresponds, therefore, to one of the cells, most 

 closely to the egg-cell or spermatozoon of higher ani- 

 mals. If every living being is descended from a single 

 cell, the fertilized egg, it is not hard to believe that all 

 higher animals are descended from an ancestor having 

 the general structure or lack of structure of the amoeba. 



But is the amoeba really structureless ? Probably it 

 has an exceedingly complex structure, but our micro- 

 scopes and technique are still too imperfect to show 

 more than traces of it. Says Hertwig : " Protoplasm is 

 not a single chemical substance, however complicated, 

 but a mixture of many substances, which we must pict- 

 ure to ourselves as finest particles united in a wonder- 

 fully complicated structure." Truly protoplasm is, to 

 borrow Mephistopheles' expression concerning blood, 

 a " quite peculiar juice." And the complexity of the 

 nucleus is far more evident than that of the protoplasm. 

 Is protoplasm itself the result of a long development ? 

 If so, out of what and how did it develop ? We can- 

 not even guess. But the beginning of life may, appar- 

 ently must, have been indefinitely farther back than 

 the simplest now existing form. The study of the 

 amoeba cannot fail to raise a host of questions in the 

 mind of any thoughtful man. 



As we have here the animal reduced, so to speak, to 

 lowest terms, it may be well to examine a little more 

 closely into its physiology and compare it briefly with 

 our own. 



