Confoymity to Enviroujnctit 



similar to that of the seal to the wax. The 

 Impression on the wax Is often far more legible 

 than the monogram engraved on the seal. We 

 may put this fact In another form. Environ- 

 ment Is really a great host of forces and tend- 

 encies pressing and crowding, luring and draw- 

 ing, the animal from all sides. But the animal 

 cannot at any one time yield In all directions. 

 All these forces unite In one grand resultant, 

 urging the animal In a certain direction. Simi- 

 larly gravitation, wind, tide, eddy, and current, 

 all unite to drive a sailboat along a steady course. 

 When we study the Impression which environ- 

 ment has made upon animals, or the resultant 

 of Its forces as shown by the directions In which 

 they have been urged, we notice that the Impres- 

 sion and resultant have continually changed as 

 they advanced from stage to stage of develop- 

 ment. During the zoophytic stage the chief 

 business of our ancestors was to develop good 

 digestion, worms had to develop muscles, early 

 vertebrates a backbone, mammals a brain. 

 Judged by Its Impression or resultant, environ- 

 ment appears successively as a power making for 

 good digestion, then for muscular power and 

 quickness of movement, then for shrewdness. 



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