298 Heredity. 



therefore be a much more rapid process than Darwin 

 believes. 



We will now examine the evidence to show that sudden 

 changes of this kind do sometimes occur. This evidence 

 is of necessity drawn almost entirely from our domesti- 

 cated animals and plants. A great gap between fossil 

 forms might be attributed to the imperfection of the 

 record, and if a wild form were to come into existence 

 suddenly it would simply be recorded as a very rare spe- 

 cies, and there would be 110 way to tell whether it is 

 the first or the last of its race. If a considerable modi- 

 fication of a well-known wild species should appear sud- 

 denly in a region which is well known and thoroughly 

 explored, we might have sufficient evidence to be certain 

 that it is due to recent variation: and there arc a few in- 

 stances of this kind, the spike-horned buck of the Adi- 

 rondacks being the most conspicuous one with which I 

 am acquainted. In Dec., 1869, a writer in the Ameri- 

 can Naturalist says that he has hunted in the Adiron- 

 dacks where the Cervus Virginianus abounds for the 

 last twenty-one years. About fourteen years ago he first 

 heard of spike-horn bucks. These became from year to 

 year more common; about five years ago he shot one, 

 and subsequently another, and now they are frequently 

 killed. He says that the spike-horn differs greatly from 

 the common antler of C. Virginianus. It consists of a 

 single spike, more slender than the antler, and scarcely 

 half as long, projecting forward from the brow, and ter- 

 minating in a very sharp point. He believes that it 

 gives a considerable advantage to its possessor over the 

 common buck, as it is a more effective weapon than the 

 common antler, at the same time that it enables him to 

 run more swiftly than the common buck through thick 

 woods and underbrush. 



