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variation ? The argument based upon the hypothesis that 
whatever is useful has been produced by Natural Selection, 
has already been considered. We will give one more 
illustration of the way in which Natural Selection is sup 
posed to intervene. 
“When the accustomed food of some animal becomes scarce or 
totally fails, the creature can only exist by emigrating or by becom 
ing adapted to a new kind of food—a food perhaps less nourishing 
and less digestible. Natural Selection will now act upon the stomach 
and intestines, and all individual variations favourable to the new 
state of things will be taken advantage of to modify the race into 
harmony with the conditions. In many cases, however, it is probable 
that this cannot be done ; the internal organs may not vary quick 
enough, and then the animal will decrease in numbers, and finally 
become extinct.”—(George St. Clair. Darwinism and Design, pft. 
73-74-) 
But several well-known instances can be adduced to 
show that some animals will choose to vary their food 
rather than perish with hunger, and that such variations 
produce a marked result on the organism. 
“ Hunter long ago observed that the muscular coat of the stomach 
of a gull (Lams tridactylus), which had been fed for a year chiefly on 
grain, was thickened ; and, according to Dr. Edmondston, a similar 
change periodically occurs in the Shetland Islands in the stomach of 
the Larus argentatus, which in the spring frequents the cornfields 
and feeds on the seed. The same careful observer has noticed a 
great change in the stomach of a raven which had been long fed on 
vegetable food. In the case of an owl (Strix grallaria) similarly 
treated, Menetries states that the form of the stomach was changed, 
the inner coat became leathery, and the liver increased in size.”— 
(The Variation, vol. zY., ft. 302.) 
In considering the argument drawn from artificial 
selection, it may be well to note a remarkable statement 
made by Mr. Fiske:— 
“ That agency is neither more or less than selection, taking advant 
age of that slight but universal variation in organisms implied by the 
fact that no two individuals in any species are exactly alike. . . . 
It is in this and no other way that our breeds of race-horses have been