PUP.E. 195 



close of my last section consists in another shedding of the 

 outer skin, when the insect appears in a totally different form, 

 during the period of which it is destined to remain in inactivity 

 and liable to destruction, were it not for the admirable instinct 

 which is exhibited by the larva before its change, in the con- 

 struction of a case or cocoon, wherein it is safely lodged 

 until its final assumption of the perfect state. A preceding 

 page (p. 8) described the cocoon of the Emperor moth, w r hich 

 will serve as an instance of the ingenuity exhibited by the 

 caterpillar for effecting this object. There are also many 

 larvae which, although the pupae are inactive, do not con- 

 struct cocoons, but merely secrete themselves in some ob- 

 scure situation, or bury themselves under ground, where 

 they hollow out a narrow cave for their repose. Others, 

 again, as the peacock butterfly, and many others, suspend 

 themselves in the open air. Another class, occurring in the 

 order Diptera, retain their larva skin, within which they 

 become pupae. This period of inactivity is not, however, 

 universal, since there are many insects which retain their 

 activity, and therefore need no cocoon for their defence. 

 This is the case with the grasshopper, cockroach, Cimex y 

 Cicada, and others. 



The state to which the insect is now arrived is technically 

 termed the pupa ; and it is this term which we must be still 

 compelled to make use of in speaking of the present state of 

 insects, since there is no English word applicable to pupae 

 in general. The terms Chrysalis and Aurelia have indeed 

 been applied to the pupae of Lepidoptera, and that of nymph 

 partially to other pupae. 



The variations which exist in the pupae of the different 

 groups of insects are much more striking than those observ- 

 able in the larvae ; hence it is not surprising that Fabricius 

 and his followers employed the name which characterizes the 

 pupa to designate the general nature of the metamorphosis, 



