Mr. Romaiies's Test. 121 



up for the changes it could not otherwise resist or 

 subdue. Instead of itself brooding, as assuredly it 

 once did, it contrived to make others do the brooding 

 for it, and, what is yet more, it also managed so to 

 impress on its young the necessity for a certain kind 

 of action in order to its own well-being and sus- 

 tenance. 1 do not say whether this is, in the terms 

 of Romanes, simple reflex action, or otherwise — the 

 fact — the necessity of certain actions in throwing out 

 the birds of the foster-parents from the nest is there, 

 and most powerfully strong and availing, and all the 

 more significant that it does not stand alone, but is 

 part of a whole crowd of changes and modifications, 

 all agreeing to secure one grand result. 



Mr. Romanes puts down as the prevaihng test the 

 following : 



" Does the organism learn to make new adjust- 

 ments, or to modify old ones, in accordance with the 

 results of its own individual experience ? If it does 

 so, the fact cannot be due to mere reflex action in the 

 sense above described ; for it is impossible that here- 

 dity can have provided in advance for innovations 

 upon, or alternations of its machinery during the life- 

 time of a particular individual." 



This points, though it was not meant to do so, 

 exactly to our difficulty as regards actions of the 

 young cuckoo, thoroughly opposed to its proper and 

 earlier instincts. 



But even these exceedingly able men, by their very 

 aptness in thinking, sometimes bring out in painful 

 prominence their lack of special knowledge or obser- 

 vation in which they ought to be pre-eminently strong. 



Here is a proof, from quite another point, of what 



