',/ 



23 



after ; fig. 1, eight months after. But this only holds good 

 as regards those pupa which lie dormant after the first stage 

 is completed, which takes about sixty hours to accomplish ; 

 they are then in a state of repose, and the nervous system 

 eeeras to remain almost inactive until the warmth of the 

 Ternal sun awakens the slumbering world to life and fresh 

 vitality. 



The insects that change to the winged state in a few days 

 have no period of rest. The larva of the small tortoishell 

 butterfly, Vanessa urticae, as soon as it is full fed, hangs 

 itself up by the tail, changes to the pupa, and in nine or 

 ten days the beautiful imago is seen sporting through our 

 gardens. Thus the period in which the insect may remaia 

 in the pupa state varies very much, from a few days to one, 

 two, or I believe even more years. Just previous to its 

 exit we shall find on examination that the insect has now a 

 very difl!'erent aspect to what it had when first it took on 

 the pupa form, the legs and antennae are formed, the spiral 

 trunk complete, the eyes, those wonderful and beautiful 

 objects, are perfected, the first ganglion and brain are one, 

 the fourth, fifth, and sixth ganglia are united; and thus 

 bear out what I before alluded to, that the largest nervous 

 developments are found where the greatest demand is made 

 for nervous power — look at the brain, surrounded with 

 highly developed organs ; the thoracic ganglia, to supply 

 the powerful wings during the period of action. Thus all 

 parts being perfected, the imprisoned insect splits the pupa 

 case down the back, the legs, antennae, and wing covering 

 become lose and detached, and the liberated prisoner creeps 

 from his earthly shroud, but his wings have yet to expand ; 

 all 18 there, every little scale or feather that gives thos 

 beautiful hues to its outstretched pinion are in a measure 

 closely compressed. The insect as soon as it escapes from 

 its tenement climbs up any object at hand, and then the 

 completion of the process takes place. The wing I must 

 inform you now is very soft and has several large vessels in 

 it, they form the ribs. As the tracheal vessels communicate 

 freely, I believe the process of expansion is entirely owing 



