Mr. A. S. Packard on the Hymenoptera. 



the thoraco-abdotninal ring, or propodeum (c), with its oblong 

 spiracle (n), essentially differing from those on the abdomen. 

 At this point the body contracts ; but the head and thorax toge- 

 ther are yet, as still more in the previous stage, much smaller 



kA "^ 



than in the pupa, and there is still a continuous curve from the 

 tip of the abdomen to the head, g, antenna; h, lingua and 

 maxillae and palpi ; i, fore legs ; j, middle legs ; k, mesoscutum ; 

 Z, mesoscutellum; m, metascutellum; w, spiracle of the propodeum. 

 Fig.^. Bombus fervidus. The third stage of the semipupa. The head 

 and thorax together now nearly equal in size the abdomen ; the 

 propodeum (c) has become entirely transferred to the thorax. 

 The head has become greatly enlarged ; the vvings are very un- 

 equal, the hinder pair are much smaller, and overlain by the 

 anterior pair ; the three terminal pairs of abdominal rings, so 

 large in fig. 2, have been absorbed, and partially enclosed in the 

 cavity of the abdomen ; and there has been a further differentia- 

 tion of the ring into the sternite {d), pleurite (c), and tergite (/). 

 a, eye ; h, lingua ; o, ovipositor, two outer rhabdites exposed to 

 view. The abdominal spiracles in figs. 2 and 3 are repre- 

 sented by a row of dots. In the pupa (fig. 4) they are concealed 

 by the tergites. 



