IS92. 



THE EVOLUTION OF FLAT-FISHES. 199 



irresponsible fashion in which the deeper problems of Biology are too 

 often discussed. There is too much striving after brilliancy and 

 originality, and far too much importance attached to these qualities. 

 In Biology, at present, it would sometimes seem that the Italian 

 epigram, se non e vera, e ben tvovato, is the verdict which authors desire 

 for their papers. When the arguments of eminent biologists exhibit 

 such an absence of logic and accuracy, such an abundance of self- 

 contradictory propositions and baseless assumptions as some that 

 have been published concerning the evolution of flat-fishes, it is small 

 wonder that the claim of Biology to rank as an exact science should 

 be questioned. 



The physiology of the organism, like the physiology of organs, 

 must be investigated by experiment. The final object of the exact 

 sciences is to trace the connection between cause and effect, to ascer- 

 tain the antecedent conditions which are not only necessary but 

 sufficient to produce observed phenomena. The rigid and exact 

 methods of experimental science have been learned and applied by 

 the physiologist who studies the functions of organs in the vertebrata. 

 But the evolutionist has still to learn the logical meaning of the 

 word " cause." He seems to think that accuracy and caution are 

 only necessary in observation and description, and that when he 

 leaves these to consider the causes of things observed, he enters a 

 region of romance, where he may soar on the wings of fancy, and 

 where discoveries can be made by a lively imagination without the 

 labour of research. 



J. T. Cunningham. 



