VADE MECUM. i) 



appioiicli of winter ; there iU'c few, the period of whose life 

 exceeds that of a year. Some outlive the rigors of winter, 

 from being concealed under ground, and others remain hid 

 in the hark of trees, or in chinks of cdd walls ; but the pro- 

 portion which survives is very inconsiderable, unless it be 

 those in the egg state. Those which are hatched in the 

 autumn, and live under ground, or in other places of security 

 during winter, usually come forth in the spring, take proper 

 nourishment, and undergo their several changes to the per- 

 fect state. 



When the insect has quitted the cxuvice of the pupa, it has 

 attained the last stage of its existence, and is termed an 

 imago, or perfect insect. Afler its first exclusion it is weak, 

 soft, and languid, and all its parts covered with moisture. 

 The wings, instead of being of their subsequent amplitude, 

 and painted with a variety of hues, are very small and of a 

 dull colour, in which no distinct characters can be traced. 

 These symptoms of debility and imperfection, however, soon 

 vanish ; the moisture of the skin evaporates ; the texture 

 becomes firm ; the colours appear in their perfect beauty ; 

 and the wings expand to their fall size. The proceedings 

 liere described, observe Messrs. Kirby and Spence, were 

 witnessed very recently in that interesting and beautifal 

 Butterfly Papilio Machaon, which 1 had the plcasm-e to sec 

 leave its puparium. With great care I placed it npon my 

 arm, where it kept pacing about above an hour ; when all 

 its parts appearing consolidated and developed, and the 

 animal in perfect beauty, I secured it, though not without 

 great reluctance, for my cabinet. To observe how gradual, 

 and yet how rapid, was the development of the parts and 

 organs, and particularly of the wings, and the perfect coming 

 forth of the colovus and spots, was an interesting .spectacle. 

 At first it was unable to elevate or even move its wings ; 

 but in proportion as the aerial or other fluid was forced by 



