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pupa apparently lacks legs and prolegs. As will be shown later, the 

 legs are always present, but folded and not in use, while the scars of 

 all the prolegs remain to show their location and are very easily 

 identified in the majority of cases. Many lepidopterous larvae possess 

 striking tubercles and warts, and usually an abundance of setae. All 

 larvae possess setae, but they are often inconspicuous. On the ex- 

 posed portions of the body surface, in so far as observed, the pupa 

 always retains the scars of these warts and tubercles, and the pupal 

 body possesses setae arranged in most cases in the exact order in 

 which they occurred in the larva. Many other structures of the larva 

 can be easily identified in the pupa, and these will be discussed later. 



In the case of insects with complete metamorphosis the name pupa 

 is applied to the stage of the insect in which it is more or less quies- 

 cent while undergoing the changes which are necessary to fit it for 

 its adult life. This word pupa, from the Latin meaning baby, was 

 applied to this stage by Linnaeus from the resemblance of certain 

 pupae to a baby which has been swathed or bound up, as was the 

 custom in many parts of Europe at that time. This name was per- 

 haps more appropriate for the pupae of the Lepidoptera than for 

 those of any other order of insects because the appendages are usually 

 all soldered to the thorax. 



The change from larva to pupa in the Lepidoptera has been 

 observed by many workers and is full of surprises for the amateur 

 who wishes to breed these insects. The caterpillar when ready to 

 pupate stops feeding, and in many instances leaves the food plant and 

 wanders about, often apparently in the greatest of haste. Many are 

 then seen on sidewalks, garden paths, and other traveled places, 

 especially during the autumn months, when the majority of larvae are 

 seeking a place to spend the winter. These larvae, if confined, will 

 refuse food and many of them spin silk threads which are used to 

 suspend the pupa or to form a cocoon. The alimentary canal is always 

 freed of any food materials. The larval skin at this time loses its 

 luster and becomes more and more wrinkled ; and the body becomes 

 shorter and shorter and appears swollen, which is due to the molting- 

 fluid glands pouring their secretions between the outer and inner 

 layers of cuticle. Some drops of a yellowish or reddish fluid are 

 usually found in the place where larvae are confined and this, together 

 with their peculiar appearance, often leads the amateur breeder of 

 Lepidoptera to think that decomposition is taking place, and results 

 in the hasty disposal of the now helpless insect. In the case of larvae 

 which spin a cocoon these changes are not so easily observed, unless 

 the cocoon is a very frail one, because most of the changes described 

 take place inside of the cocoon. These changes may occupy but a few 



