EVIDENCES FROM MORPHOLOGY 145 
limestone caverns under nearly the same climate in the two continents 
of America and Europe; so that, in accordance with the theory of 
special creation, very close similarity in the organizations of the two 
sets of faunas might have been expected. But, instead of this, the 
affinities of these two sets of faunas are with those of their respective 
continents—as of course they ought to be on the theory of evolution. 
Again, what would have been the sense of creating the useless foot- 
stalks for the imaginary support of absent eyes, not to mention all the 
other various grades of degeneration in other cases? So that, upon 
the whole, if we agree with the late Professor Agassiz in regarding 
these cave animals as furnishing a crucial test between the rival 
theories of creation and evolution, we must further conclude that the 
whole body of evidence which they now furnish is weighing on the 
side of evolution. 
So much, then, for a few special instances of what Darwin called 
rudimentary structures, but what may be more descriptively desig- 
nated—in accordance with the theory of descent—obsolescent or 
vestigial structures. It is, however, of great importance to add that 
these structures are of such general occurrence throughout both the 
vegetable and animal kingdoms that, as Darwin has observed, it is 
almost impossible to point to a single species which does not present 
one or more of them. In other words, it is almost impossible to find 
a single species which does not in this way bear some record of its own 
descent from other species; and the more closely the structure of any 
species is examined anatomically, the more numerous are such records 
found to be. Thus, for example, of all organisms that of man has 
been most minutely investigated by anatomists; and therefore I think 
it will be instructive to conclude this chapter by giving a list of the 
more noteworthy vestigial structures which are known to occur in the 
human body. I will take only those which are found in adult man, 
reserving for the next chapter those which occur in a transitory manner 
during earlier periods of his life. But, even as thus restricted, the 
number of obsolescent structures which we all present in our own 
person is so remarkable, that their combined testimony to our descent 
from a quadrumanous ancestry appears to me in itself conclusive. 
I mean, that even if these structures stood alone, or apart from any 
more general evidences of our family relationships, they would be 
sufficient to prove our parentage. Nevertheless, it is desirable to 
remark that of course these special evidences which I am about to 
detail do not stand alone. Not only is there the general analogy 
