Introdcctiox. xvii 



loose, something like a firm felty substance ; others are very hard and firm, especially if shavings 

 have been used in their construction ; and sometimes they are quite smooth and parchment-like. 

 The cocoons are generally placed in hidden or protected situations, some in corners, in crevices 

 of trees, in the ground, or under moss, and the outside is often difficult to distinguish from 

 surrounding substances! Cocoons attached to the trunks of trees are often very skilfully 

 constructed, and covered with pieces of bark and lichen so as perfectly to resemble a natural 

 excrescence of the bark. The form of the cocoon is generally egg-shaped, but some are spindle- 

 shaped, pear-shaped, or boat-shaped. Others resemble a bottle with a short neck, and have a 

 valve-like partition at the base inside, and others are closed by a kind of lid. The larvae which 

 feed in the interior of the hard portions of plants prepare a path by which the moth can escape, 

 before they assume the pupa state. This generally consists of a tube or passage from the place 

 where the pupa rests, to the outer wall, where it is closed by the outermost skin of the plant. 

 Case-bearing larvae do not prepare a special cocoon, but fasten the upper end of the case to some 

 object, and then turn round inside before assuming the pupa state. The moth afterwards emerges 

 from the hinder end. Larva; which live between leaves which they have spun together generally 

 make no regular cocoon, but change to pupae between the leaves where they have lived, or else go 

 into the ground for the purpose. Most of the naked larvae of Macro-Lcpidoptcra, except those of 

 the butterflies, undergo their transformation in or on the surface of the ground, sometimes without 

 any preparation. Some of those which change on the surface of the ground do so between two 

 leaves, which they draw together around' them ; and others which change beneath the surface 

 construct a sort of cocoon of agglutinated grains of earth, which may be either loose or firm, and 

 is generally lined with silk. The transformation to a pupa is efi"ected by the swelling of the front 

 segments till the skin of the larva splits at the back of the neck, and is shuffled off behind by 

 continuous movements of the pupa. When the pupa first appears it is often soft and pale, but 

 soon acquires its proper colour and consistency. The larger and more complicated cocoons 

 frequently require a day or more for their completion. 



PUP.€. 



• 



Form and Colour.— The shape of the pupa is generally cylindrical, becoming narrower behind, 

 either gradually or suddenly. It is surrounded with a horny skin varying in hardness, and is 

 divided into the thorax, corresponding to the thoracic segments of the larva ; and the abdomen, 

 which consists of nine movable rings jointed together. The separate parts of the future butterfly 

 may be plainly noticed on the outside of the thora.x of the pupa, in the seams by which the cover- 

 ing is divided. The head is indicated by a slight swelling in front. It is pressed downwards, and the 

 eyes are visible on each side. Behind and above this is a narrow segment, the pro-thorax; then the 

 large and broad meso-thorax, and behind this the short meta-thora.x. The lower joints of the two 

 first pairs of legs are placed on the under side in front, on the side of the head, while their thighs 

 and the last pair of legs are concealed, except that the extremities of the latter are visible behind 

 the other legs. The antennas pass round the eyes, and run backwards outside the middle pair of 

 legs, which they thus enclose. The cases of the fore-wings rise on the sides of the meso-thora.x, and 

 run backwards and beneath, bordering the antenna;, and meet towards the ends, or are separated 

 by the legs, antennae, and tongue, according to the length of these organs. The hind-wings are 

 attached to the meta-thorax, but there is only a small part of their base visible, because they are 

 hidden under the fore-wings. The winc^-cases usually extend at least as far as the middle of the 

 pupa, and are always conspicuous beyond the meta-thorax. They sometimes reach as far as the end 

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