66 



THE CLASS OF INSECTS. 



Fig. 64 shows what we may call the semipupa, concealed by 

 the larval skin. There are eleven pairs of stigmata, three 

 thoracic and eight abdominal. The head of the semi-pupa 

 lies under the head (a) and prothoracic ring (b). The basal 

 ring of the abdomen (c), or fourth ring from the head, is un- 

 changed in form. This figure also will suffice to represent 



g a 



Fig. 65. 



771 



Fig. 67. 



the larva, though a little more produced anteriorly than in 

 its natural form. 



In another stage (Fig. 65) of the semi-pupa, the larval skin 

 is entirely sloughed off, the two pairs of wing-pads lying paral- 

 lel, and very equal in size, like the wings of Neuroptera. The 

 thoraco- abdominal ring, or propodeum (c), is distinguished by 

 its oblong spiracle (n), essentially differing from those on 

 the abdomen. At this point the body contracts, but the head 



