162 Evolution and Adaptation 
shall appear at the places whence the lateral ribs start, and 
that here also a definite acute angle shall be preserved.” 
Thus the philosopher in his closet multiplies and magnifies 
the difficulties for which he is about to offer a panacea. Had 
the same amount of labor been spent in testing whether the 
life of this butterfly is so closely dependent on the exact imi- 
tation of the leaf, we might have been spared the pains of 
this elaborate exordium. There are at least some grounds 
for suspicion that the whole case of Kallima is ‘made up.” 
If this should prove true, it will be a bad day for the Darwin- 
ians, unless they fall back on Weismann’s statement that 
their theory is insufficient to prove a single case! 
Weismann has used Kallima only as the most instruc- 
tive illustration. The objections that are here evident are 
found not only in the cases of protective coloration, but “ are 
applicable in all cases where the process of selection is con- 
cerned. . Take, for example, the case of instincts that are 
called into action only once in life, as the pupal performances 
of insects, the fabrication of cocoons, etc. How is it that 
the useful variations were always present here?” Weismann 
concludes that “something is still wanting to the selection 
theory of Darwin and Wallace, which it is obligatory on us 
to discover, if we possibly can, and without which selection 
as yet offers no complete explanation of the phyletic processes 
of transformation.” Weismann’s first step in the solution of 
the difficulty is contained in the following statement: — 
“My inference is a very simple one: if we are forced by 
the facts on all hands to the assumption that the useful 
variations which render selection possible are always present, 
then, some profound connection must exist between the utility 
of a variation and tts actual appearance, or, in other words, 
the direction of the variation of a part must be determined by 
utility, and we shall have to see whether facts exist that con- 
firm our conjecture.” 
Weismann finds the solution in the method by which the 
