156 The Bible of Nature 



mutationSy in which something new emerges sud- 

 denly without gradual stages and with no small 

 degree of perfectness. Using Galton's simile we 

 can picture a polyhedron oscillating or rocking 

 on one of its faces, this would be fluctuation; 

 we can picture it rolling over to a position of 

 equilibrium on another face, this would be 

 mutation. 



Though there is some truth In Lamarck's saying 

 that ''Nature is never brusque," and though we 

 may justifiably disbelieve entirely in grotesque 

 " Jack-in-the-Box " phenomena, such as Bastian's 

 *' Heterogenesis " (e. g.y the origin of a large infu- 

 sorian by the transformation of a Rotifer's egg), 

 which would make Nature magical and irrational, 

 we now know, through the work of Mr. Bateson 

 and others, that discontinuous variations are not 

 rarities. In particular we know through the beau- 

 tiful work of De Vries on *' Evening Primroses and 

 Other Plants," that organisms may give rise to 

 offspring which are distinctively new, and that 

 these are mutations come to stay. Such words as 

 "freaks" and "sports" are not very happy, but 

 they suggest the idea of what Mr. Galton calls 

 " transilient " variations — the fact that organic 

 structure may pass with seeming abruptness from 

 one position of organic equilibrium to another. 

 We have, in short, to deal with a Proteus who 

 leaps as well as creeps. 



