Packard.] 



294 



of which have become, we must believe, extinct. The Neuroptera 

 are moreover true synthetic types, combining, as do all decephalized, 

 embryonic forms, the structure of several e(juivalent groups, present- 

 ing features which remind us of characters more fully wrought out in 

 higher and more compactly finished groups of insects. 



k I 



h ■■■:.. 



Fig. 1. 



Fig. 2. 



Fig. 3. / Fig. 4. 



DESCRIPTIONS OF THE FIGURES. 



Fir/. 1. Bombus fervidus. The first stage of the semi-pupa con- 

 cealed by the larval skin. The semi-pupa head lies under the head 

 (a) and the prothoracic ring (h). The basal ring of the abdomen ((•) 

 or fourth ring from the head is unchanged m form. This figure also 

 will suffice to represent the larva, though a little more produced ante- 

 riorly than in its natural form. 



