138 HEREDITY AND " ARRANGEMENT r 



" arranged," and this something can hardly be 

 other than material if it is to be " arranged " at 

 all. But let that pass. What is far more im- 

 portant is to remember that if a thing is to be 

 " arranged " there must be somebody to 

 " arrange " it, for chance-medley cannot " ar- 

 range " anything in an orderly manner ; or if it 

 could do so once, cannot be supposed capable of 

 doing it a second time in a precisely similar 

 manner, not to say capable of doing it countless 

 thousands of times. 



If we go into a great museum our first idea, 

 perhaps our last, concerns the arrangement found 

 therein. But it may safely be said that no sane 

 person ever entertained that idea without being 

 perfectly aware that the arrangement was made 

 by human hands, controlled, in the last resort, 

 by the brain of the curator of the museum. 

 Now, in a sense, the living body is a museum 

 containing specimens of different kinds of cells. 

 There are brain-cells, liver-cells, bone-cells, scores 

 of different varieties of cells, and all of them, so 

 to speak, are arranged in their appropriate cases. 



If we go to the brain-case we can search it 

 through and through without finding a liver-cell, 

 any more than we should find a typical brain-cell 

 embedded in the marrow of one of the bones. 

 The different specimens all occupy their appro- 

 priate positions. How did they get there ? 

 The future animal, like animals of all kinds, in- 

 cluding man, commences as a single cell. All 

 save a few interesting but at present negligible 

 cases are composed of elements drawn from male 



