92 



INTRODUCTION TO 



presents the appearance delineated in the adjoiuin e 

 wood-cut. 



3 ^-^ 



The pupa having made so much nearer an ap 

 proach to the perfect form than the larva, exhibit 

 some indication of the principal divisions of the hod; 

 which afterwards become so strongly marked. A 

 slight constriction frequently points out the bound-* 

 aries of the head, thorax, and abdomen. Regarding 

 the exterior sheath as the case (theca) of the pupa 

 Kirby and Spence have assigned a nomenclature to 

 its principal parts : the anterior division enclosing the 

 head, is called the Head-case (cephalo-theca) ; nex 

 to this is the Trunk-case (cylo-theca) ; and lastly the 

 Abdomen-case (gastro-theca). The coverings of 

 the other parts receive names from the Greek word 

 for these parts compounded with theca; thus the 



