VIII 



LARVA AND NYMPH iii 



Quite unlike to what occurs with plants, light 

 does not influence insect-colouring, nor even quicken 

 it. It must be so, since in the species most gifted 

 with splendid colour — Buprestids and Carabids for 

 instance — the wonderful hues that would seem stolen 

 from a sunbeam are really elaborated in darkness, 

 deep in the ground, or in the decayed trunk of some 

 aged tree. 



The first indication of colour is in the eyes, 

 whose horny facets pass successively from white to 

 tawny, then to a slaty hue, and lastly to black. The 

 simple ones at the top of the forehead share in their 

 turn in this coloration before the rest of the body 

 has at all lost its whitish tint. It should be noted 

 that this precocity in the most delicate of organs, 

 the eye, is general in animals. Later a smoky line 

 appears in the furrow separating the mesothorax 

 from the metathorax, and four-and-twenty hours 

 later the whole back of the mesothorax is black. 

 At the same time the division of the prothorax 

 grows shaded, a black dot appears in the central 

 and upper part of the metathorax, and the mandibles 

 are covered with a rusty tint. Gradually a deeper 

 and deeper shade spreads over the last segments of 

 the thorax, and finally reaches the head and sides. 

 One day suffices to turn the smoky tint of the head 

 and the furthest segments of the thorax into deep 

 black. Then the abdomen shares in the rapidly 

 increasing coloration. The edge of the anterior 

 segments is tinted with daffodil, while the posterior 

 segments acquire a band of ashy black. Then the 

 antennae and feet take a darker and darker tint, till 

 they become black, all the base of the abdomen turns 



