Variation and Heredity ans 
specimens. But it does not at all follow because these inter- 
mediate forms have been found to exist, that they were the 
very stages that were passed through in the course of evolu- 
tion. Counter evidence exists in abundance, not only of the 
appearance of considerable sports, but of their remarkable 
stability in hereditary transmission.” Comparing such an 
apparently continuous series with machines, Galton con- 
cludes, “If, however, all the variations of any machine that 
had ever been invented were selected and arranged in a 
museum, each would differ so little from its neighbors as to 
suggest the fallacious inference that the successive inven- 
tions of that machine had progressed by means of a very 
large number of hardly discernible steps.” 
Bateson, also, in his “ Materials for the Study of Variation,” 
speaks of the two possible ways in which variations may arise. 
He points out that it has been tacitly assumed that the tran- 
sitions have been continuous, and that this assumption has 
introduced many gratuitous difficulties. Chief of these is 
the difficulty that in their initial and imperfect stages many 
variations would be useless. ‘Of the objections that have 
been brought against the Theory of Natural Selection, this 
is by far the most serious.” He continues: “The same 
objection may be expressed in a form which is more correct 
and comprehensive. We have seen that the differences be- 
tween species on the whole are Specific, and are differences 
of kind forming a discontinuous Series, while the diversities 
of environment to which they are subject are, on the whole, 
differences of degree, and form a continuous Series; it is, 
therefore, hard to see how the environmental differences can 
thus be made in any sense the directing cause of Specific 
differences, which by the Theory of Natural Selection they 
should be. This objection of course includes that of the 
utility of minimal Variations.” 
“ Now the strength of this objection lies wholly in the sup- 
posed continuity of the process of Variation. We see all 
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