66 DEVELOPMENT AND HEREDITY. 



functions when all connection with the meagre 

 central nervous system is cut off. In many cases 

 no nerves can be traced to certain organs, and yet 

 they perform their functions perfectly. The lower 

 we descend in the scale of life the less noticeable 

 does the visible central nervous system become both 

 in its structure and in its function. The organs 

 seem to act independently of visible nervous struct- 

 ures, and yet they act harmoniously for the main- 

 tenance of the entire organism. In many of the 

 lowest animals no trace of a visible nervous structure 

 has been found ; yet here also the organs perform 

 all their functions as a harmonious whole. All the 

 actions and functions necessary for the life of the 

 individual and of the race are performed with as 

 much regularity and perfection as among animals 

 possessing highly developed nervous structures. The 

 functions of a nervous system are performed, though 

 the nervous stritctnres are not discernible. So great 

 is the similarity in motions and in the performance 

 of all the functions of life between these nerve- 

 less organisms and the higher animals, that we are 

 compelled to believe that, just as some of the low- 

 est animals can digest food in all parts of their 

 minute bodies, so also the nervous property may 

 reside in all parts. Since the same results of nutri- 

 tion, growth, etc., are accomplished among the low- 



