THE ORIGIN OF ORNAMENTATION. 511 



moths ; wliile in the lowest tribes there are many examples of almost uni- 

 form drab or brown coloring throughout. To this last statement, however, 

 many exceptions could be given of insects with front wings pictured with 

 variegated designs of such excessive minuteness that their real beauty can 

 be api)reeiate(l only when the siu'face is magnified. 80, too, in the large 

 family of Phalaenidae, or geometrids, we have moths which often fly by 

 day, and rest with all their wings fully expanded ; and here the liind wings 

 are ornamented as well as the front pair. 



It is, however, only when we come to the butterflies, the highest Lepi- 

 doptera, that we find, as a general rule, all the wings and both surfaces 

 highly ornamented. Even within this group we may see differences cor- 

 responding to their relative perfection of structure ; for in the lowest family 

 sombre colors prevail, and in very many instances the under surface is almost 

 uniform in tint ; while, with the sole exception of those l^utterflies known 

 as swallow-tails, the most variegated and exquisite patterns are to be 

 found in the highest families, and are far more generally distributed 

 among them. 



I am not aware that such a direct relation between beauty and rank has 

 been pointed out in other groups of the animal kingdom. There can be 

 no question of its existence here, and in an order of animals at once a 

 synonym for all that is delicate and exquisite it is what should be expected 

 on the theory that the lower represent earlier and the higher later forms 

 developed from a common stock. That complicated or variegated pat- 

 terns of coloring must have had their source in simpler and less varied 

 designs, and these in slight variations from an absolutely uniform tone of 

 color will not be denied by any who believe in the evolution of complicated 

 structural forms from those of simpler organization ; and must be regarded 

 as possible if not probable by all who study the past life of the globe and 

 see the march of life, with its constant tendencies to differentiation. 



It should be borne in mind that, so far as the direct influence of physi- 

 cal agencies is concerned, we are dealing here with a class of facts very 

 different from those we meet in discussing the ornamentation of vertebrated 

 animals. In birds and quadrupeds, the feathers, hair, and other dermal 

 appendages have developed to maturity and even wasted and been replen- 

 ished under all the vicissitudes to which animal life is exposed during a 

 period of several years. In butterflies, on the contrary, the ornamenta- 

 tion we are considering is confined to the brief final epoch of life, there is 

 no replenishing of the scale-tissue, and the scales are formed rapidly and 

 once for all, at a definite period, viz., immediately upon the change from 

 larva to pupa ; and being then concealed from light and excesses of tem- 

 perature within a thick integument, and often also behind the walls of a 

 dark chamber of silk, vegetable fibres, or earth, they are as far removed 

 as possible from external agencies. In the depths of this retreat the 



