464 



COMPARATIVE PHYSlOLOaY. 



Fig. 330.— Group of cells in connection with anterior roots of spinal nerves, as seen in 

 transverse section of spinal cord of sheep (after Flint and Dean). A, emergence 

 of anterior roots from gray matter; b, 6, b, cells connected both with each other 

 and with fibers of anterior roots. 



very large extent, as may be shown by experiment, yet it can 

 not be too well borne in mind that in the actual normal life of 

 an animal such purely independent behavior must be exceed- 

 ingly rare. We are constantly in danger, in studying a sub- 

 ject, of making in our minds isolations which do not exist in 

 nature. When one accidentally sits upon a sharp object, he 



