754 GEOLOGICAL SUCCESSION OF THE ECHINI. 



estimated. His influence on the progress of biology has been most bene- 

 ficial, and he lias, in connection with the embryologists, led the way for 

 biology «nit of the mere systematic field which threatened at one time to 

 stop all future progress. But his disciples cannot ask us to take as proved 

 beyond question all the vagaries regarding this and that ancestor of the great 

 types of the animal kingdom, about which they talk with such sublime con- 

 fidence. And when I am introduced to an archetype in a group where we 

 have neither paleontological nor embryological evidence, or when 1 am asked 

 to believe in a genealogical tree of which neither the roots nor the branches 

 have ever existed, as far as we now know, I am no longer dealing simply 

 with an hypothesis, but with the wildest speculation. 



Specialists are supposed to be least fitted to form opinions on general 

 philosophical questions for which their investigations may have furnished 

 valuable data. Vet. unlit as they may be to decide between two rival sys- 

 tems of philosophy, they should at any rate be credited with sufficient intel- 

 ligence to know whether a theorv accords with the facts in the case or not, 

 and explains it satisfactorily. The supporters of Darwin, who outdarwin 

 Darwin himself, seem determined not to imitate their great leader, and at- 

 tempt, in the most dogmatic manner, to crush any argument brought forward. 

 not by showing its worthlessness, but by simply taking it for granted that 

 discussion is no longer possible. 



