As a rule there is no marked resemblance between the different stages of the same insect. Thus, a brilliantly coloured caterpillar may change to a dull and unattractive chrysalis, from which may emerge a butterfly or moth that partakes of the colours of neither. But in a few cases there _are_ colours or other features that remain persistent throughout the three stages, or show themselves prominently in two. An interesting example in point is that of the Magpie or Currant Moth (page 279). The caterpillar of this moth is cream-coloured, with orange stripes along the sides, and very bold black markings down the back. The chrysalis, which is at first entirely yellow, afterwards turns black with the exception of some yellow transverse bands. Then, the moth exhibits the same colours as these two earlier stages, with the same degree of boldness; for its pale cream-coloured wings, tinted with patches of yellow, are marked with numerous deep black spots. Thus, in this case, we find the same general character of the colouring throughout the insect's existence. [Illustration: FIG. 34.--THE PUPA OF THE CURRANT MOTH.] [Illustration: FIG. 35.--PUPA OF THE PALE TUSSOCK MOTH (_Pudibunda_).] Another interesting example, though not so striking as the last, is to be found in the case of a group of moths known as the _Liparidae_. The caterpillars of these are remarkable for their very hairy bodies, often ornamented by several bold brush-like tufts. The chrysalides are also hairy; and several of the moths themselves are not only thickly clad with shaggy hair, but a bold tuft often tips the abdomen. We must not leave these few remarks on the characters of chrysalides without a mention of the brilliant spots of burnished gold that decorate the pupae of certain butterflies. This is the feature that led to the invention of the term _chrysalis_, which is derived from the Greek word _chrysos_, meaning _gold_. For the same reason the term _aurelia_ has been applied to the pupae of _Lepidoptera_, this being derived from _aurum_--the Latin name for gold. Strictly, then, these two terms apply only to the pupae of a certain number of the butterflies; but the former is now generally used to designate the pupae of all the _Lepidoptera_, and is even extended to the corresponding stages of insects of other orders. If you examine one of these gold-speckled chrysalides, the brilliant metallic lustre seems to belong to the outer surface, just as if certain spots had been tipped with real gold; but after the butterfly has quitted its case the beautiful golden spots are gone. This proves that the metallic appearance is not due to reflection from the outer surface of the chrysalis, but to a reflection from some structure beneath it. This latter is a very thin membrane which lies just under the outer transparent covering of the chrysalis.