22 Colouration in Animals and Plants. 



function of the part emphasized. They recognise the fact that to 

 give sublimity and grace to a building, the ornamentation must be 

 related to the character of the building as a whole, and to its parts 

 in particular. 



Thus in a tower whose object or function is to suggest height, 

 the principal lines of decoration must be perpendicular, while in the 

 body of a building such as a church, the chief lines must be 

 horizontal, to express the opposite sentiment. So, too, with indi- 

 vidual parts. A banded column, such as we see in Early English 

 Gothic, looks weak and incapable of supporting the superincumbent 

 weight. It suggests the idea that the shaft is bound up to 

 strengthen it. On the other hand, the vertical flutings of a Greek 

 column, at once impress us with their function of bearing vertical 

 pressure and their power to sustain it. 



This principle is carried into colour in most of our useful arts. 

 The wheelwright instinctively lines out the rim and spokes and does 

 not cross them, feeling that the effect would be to suggest weak- 

 ness. Moreover, in all our handicraft work, the points and tips are 

 emphasized with colour. 



This principle seems to hold good throughout nature. It is not 

 suggested that the colouration is applied to important parts in 

 order to emphasize them, but rather that being important parts, they 

 have become naturally the seats of most vivid colour. How this 

 comes about we cannot here discuss, but shall refer to it further on. 



It is owing to this pervading natural principle, that we find the 

 extreme points of quadrupeds so universally decorated. The tips 

 of the nose, ears and tail, and the feet also proclaim the fact, and 

 the decoration of the sense organs, even down to the dark spots 

 around each hair of a cat's feelers, are additional proofs. Look, for 

 instance, at a caterpillar with its breathing holes or spiracles along 

 the sides, and see how these points are selected as the seats of 

 specialized colour, eye-spots and stripes in every variety will be 

 seen, all centred around these important air-holes. 



This leads us to our second principle, that of repetition, which 

 simply illustrates the tendency to repeat similar markings in like 

 areas. Thus the spiracular marks are of the same character on 

 each segment. 



The principle of repetition, however, goes further than this, and 

 tends to repeat the style of decoration upon allied parts. We see 

 this strongly in many caterpillars in which spiracular markings are 



