24 THE INTERNATIONAL MONTHLY. 
The genealogical problem for animals is precisely analogous to 
that of the science of language. In both sciences the attempt is 
made to trace the development of the modern from the ancient, 
to demonstrate the common origin of things now widely sepa- 
rated and differing in all apparent characteristics, and to make 
clear the manner in which this evolution and differentiation have 
been effected. It is regrettably true that, at the present time, 
biology still lags far behind philology with regard to the solution 
of these analogous problems, and is, indeed, in much the same 
stage of progress as was etymology when it called forth Vol- 
taire's famous sneer, " Etymology is a science in which the 
vowels count for nothing and the consonants for very little." 
Of the genealogical trees and tables constructed to exhibit the 
mutual relationships of animals few have any better foundation 
than the " guessing etymologies " of the eighteenth century, and 
for exactly the same reason. The old etymologists had no 
test to distinguish a true derivation from a false one except a 
likeness in sound and meaning in the words compared, and the 
modern zoologist is likewise without any criterion of the rela- 
tionship of animals, except certain likenesses and unlikenesses of 
structure. How great a value is to be allowed to a given simi- 
larity and how far this is offset by an accompanying dissimilarity, 
we have, as yet, few means of determining. Those laws of 
organic change are still to be discovered which shall render to 
zoology the same service as Grimm's law has done to the study 
of the Aryan tongues. Etymology was established upon a firm, 
scientific basis by laboriously tracing back the changes of words, 
step by step, from their modern forms to their ancient origins. 
The same principle must be adopted in zoology, and until a cer- 
tain number, at least, of animal series can be traced back to their 
far distant ancestors, the law of change must remain conjectural 
and largely a matter of individual judgment. 
The principal methods by which the genealogical problem may 
be attacked are comparative anatomy, embryology, and palaeon- 
tology. Each of these branches of zoology has its own partic- 
ular advantages, but each has also its especial limitations and 
