The Scents of Flowers 



attracted or warned off different animals, but he 

 did not do so. There is no difficulty in finding 

 hundreds of examples, and the common buttercup 

 is as good an instance as any of the way in which 

 animals are warned from dangerous plants by this 

 very acute sense of smell. To us the scent of a 

 buttercup is almost imperceptible, but to the cow 

 the scent is sufficiently strong to protect the plant 

 from being eaten. It is most curious to examine 

 a field full of buttercups in which cows are grazing. 

 In some years the field seems to be nothing but 

 buttercups, a veritable cloth of gold, yet the cows 

 go through it, eating all the grasses but leaving 

 both the leaves and flowers of the buttercup un- 

 touched. In this way the life of the buttercup is 

 preserved, and as far as we can see it owes its 

 preservation entirely to its scent. The colour 

 would not deter the cows, for they eat many 

 yellow flowers, nor would the acrid taste or shape 

 of the leaves deter them, for from the relative 

 position of the eyes and mouth of the cow when 

 feeding it is certain that they cannot see the 

 actual plant they are feeding on, and so it can 

 only be by the scent that they are warned from 

 it. And if animals are deterred from some 

 plants by their scent, it is by the scent that they 

 are attracted to others. It is not known for 

 certain how night moths are attracted to flowers 

 whether it is by sight or smell, but it seems most 

 probable that they are attracted in some cases by 

 sight and in some by smell, and in some by both 

 III 



