specific modifications of Japan Carahi. 521 



exclude the air, which would obliterate delicate structure 

 on the interstices. The beautiful moth, Urania, from 

 Madagascar is highly coloured on both sides, and par- 

 ticularly on the under surface, after the manner of the 

 Buprestidce, and doubtless from the same cause. I look 

 on this moth as one of the oldest forms of Lepidoptera, 

 though not so old as the Buprestidcs, for colour would 

 appear sooner on its wings than on the harder elytra of a 

 beetle. How Lepidoptera of this type of beauty preserve 

 their colours, — and there are numbers in the tropics, — I 

 do not clearly see. Papilio thoas, too, is worth looking at, 

 as it exhibits a type of pattern common in its family. The 

 pattern of the wing seems regulated by aero- and photo- 

 plasticity ; the yellow band does not j)ass over the space 

 which is open by the presence of the thorax during rest, 

 and, if the idea of this is carried in mind, it is curious 

 how soon the eye catches its influence as a cause of pat- 

 tern. These factors are acting in all quarters of the globe 

 on all Ehopalocera ; so there is no reason for seeking 

 affinity where we discover mere similarity in pattern. 

 When butterflies show signs of bright colour in the con- 

 cavity of the hind wings, it is because this part fits 

 tightly over the abdomen when they rest. 



We are fond of speaking of the simplicity of Nature's 

 operations, yet do we always see how really simple it is ? 

 Butterflies and birds living in the air seem to me clothed 

 by it, and they are made beautiful by the solar-ray 

 which passes through it. The complex nature of living 

 organisms is the result of modification through im- 

 measurable periods, not from a complex physiological 

 economy at birth. 



When we observe an exceptional structure or colour in 

 an animal, and see the peculiarity repeated, again and 

 again, in creatures which are so wholly different that we 

 can only see this peculiarity to connect them, we are 

 right in thinking there is no real affinity, or one exceed- 

 ingly remote. But we can trace the origin of the ex- 

 ceptional form or colour to the same source, for we find 

 it everywhere fulfilling the same service. We must, 

 however, look at things closely ; we must not say, that 

 the colour of a Carahus, agrees with that of a Buprestis, 

 because their tints do not absolutely correspond, and 

 we know something of the reason, as one originates in a 

 clear, dry, mountain atmosphere, and the other in the hot 

 steamy vapour of an undrained jungle. 



