of their proper food plant, must not, nevertheless, considerable 
numbers survive by contenting themselves with other allied food 
materials, and so give rise to varieties whose origin we do not dream 
of, and which therefore we are led to regard as new species?’”— 
(Beddard. Animal Coloration, ftp. 52-3.) 
“Nocturnal species which live exclusively on conifers, have dull 
colours, usually grey, as, for example, our fine Hawk-moth, or the 
Pine Spinner, and several foreign species. This is so invariably true, 
that Koch was able to conclude from the colours of certain species 
from Sydney and Baltimore that the caterpillars lived upon coniferous 
plants, and when he suggested that they should be sought on such 
plants, his conclusion was found to be correct.”—(Eimer. Organic 
Evolution, ft. 130.) 
“ Mr. Goss found that the larva of one of our Fritillaries (.Meliioea 
arte?nis) when fed upon honeysuckle, which is not the usual food- 
plant of the caterpillar, became very dark-coloured imagos. One of 
the Thorn-moths (.Ennomos a7tgularia) shows variations in colour 
according as to whether the larva has been fed upon oak, hawthorn, 
lime, or lilac.”—(Beddard. Ibid. ft. 49.) 
Structure also affects the colours of organisms. 
“Mr. Tylor has called attention to an important principle which 
underlies the various patterns or ornamental markings of animals, 
viz., that diversified coloration follows the chief lines of structure and 
changes at points, such as the joints, where function changes. He 
says:—‘In butterflies the spots and bands usually have reference to the 
form of the wing and the arrangement of the nervures, and there is 
much evidence to show that the primitive markings are always spots 
in the cells, or between the nervures, or at the junction of nervures, 
the extension and coalescence of these spots forming borders, bands, 
or blotches, which have become modified in infinitely varied ways.’”— 
(Wallace. Darwinism, ftp. 288-9.) 
The organisms of certain caterpillars seem to be modi 
fied in colour through the photographic power of reflected 
light, which assumes the tint of the substance from which 
it is reflected, as in the case of the child holding the yellow 
flower of the buttercup to the cheek of his companion. 
Some caterpillars of the small cabbage butterfly (.Pontia 
rapae) were confined by Mr. J. W. Wood in boxes lined