522 
been begun or afterwards developed by means of Natural Selection. 
For if it be not even yet of any conceivable use to its possessor, 
clearly thus far survival of the fittest can have had nothing to do 
with its formation. On the other hand, seeing that electric organs 
when of larger size, as in the Gymnotus and Torpedo, are of obvious 
use to their possessors . . . the organ in the skate seems to be 
on its way towards becoming such an organ as we meet with in these 
other animals. . . . Professor Ewart’s investigations go to indi 
cate that the organ is here not in a state of degeneration but of 
evolution. For instance, in Raid radiata it does not begin to be 
formed out of the muscular tissue until some time after the animal 
has left the egg-capsule and assumed all the normal proportions 
(though not yet the size) of the adult creature. . . . Moreover, 
it does not attain its full development (i.e., not merely growth, but 
transforming of muscular fibres into electrical elements) till the fish 
attains maturity. ... If, for the sake of saving an hypothesis, 
we assume that the organ, as it now stands, must be of some use to 
the existing skate, we should still have to face the question :— 
Of what conceivable use can those initial stages of its formation have 
been when first the muscle-elements began to be changed as the very 
different electrical-elements, and when therefore they became useless 
as muscles while not yet capable of performing even so much of the 
electrical function as they now perform ? Lastly, in the formation of 
this structure, there has been needed an altogether unparalleled 
expenditure of the most physiologically expensive of all materials— 
namely, nervous tissue. . . . We are forced to conclude that 
Natural Selection ought strongly to have opposed the evolution of 
such organs.”—(.Darwin and After Darwin, pp. 365-372.) 
Mr. Romanes admits that the difficulty presented by this 
case is of a magnitude and importance altogether un 
equalled by that of any other case. “ If there were any 
other cases of the like kind to be met with in nature, I 
should myself at once allow that the theory of Natural 
Selection would have to be discarded.”* But as there are 
not, Mr. Romanes thinks that probably some explanation 
will be offered to account for this in accordance with 
Darwinian principles, as in the case of the conspicuous 
colouring of caterpillars. 
But, as we have seen, there are other cases, in which 
experts have supposed that there was evolution without 
* P- 373-