23 



jections and ridges of various types especially in the Papilionoidea. 

 These projections have no morphological significance. 



THK HEAD 



The usual sclerites found in the head of generalized insects may 

 be located in lepidopterous pupae. The sutures are distinct in gen- 

 eralized pupae, but are obliterated in the more specialized groups. 



Vertex. — This is an area found on the dorsum of the head. It 

 reaches its highest development in the Gracilarioidea, but is usually 

 distinct in all generalized pupae. It is bounded cephalad by the Y- 

 shaped epicranial suture (es), and may be seen in Figures 3, 25, 29, 

 33' 49' 53' and 56; v. This area was referred to by Chapman and 

 Packard as the dorsal head-piece. 



Front. — The front is the sclerite to which the antennae are at- 

 tached. It is bounded by the epicranial suture on the dorsal surface, 

 and on the ventral surface by the fronto-clypeal suture, which nor- 

 mallv extends for a short distance caudad from the base of each an- 

 tenna and then transversely to the median line. In some pupae where 

 there is a "shoving back" of the head parts as in the Pyraustidae (Fig. 

 76) and Sphingidae, the front is located on the dorsum of the head. 

 The fronto-clypeal suture is usually not distinct except in very gen- 

 eralized forms. The superfamily Gelechioidea, however, shows it 

 very distinctly. It is indicated in Figures i, 8, 26, 30, and 36; f. In 

 generalized pupae the front bears two setae on each side of the meson 

 which are often very conspicuous. 



Genae. — These sclerites are distinctly bounded in Eriocraniidae 

 and Hepialidae (Figs, i and 8, g). They are found laterad of the 

 front and clypeus, and mesad of the glazed eye. The mandibles are 

 alwavs adjacent to the genae at their lateral margins. 



Clypeus. — Remarkably few pupae have the clypeus definitely 

 bounded. The suture between the clypeus and labrum is seldom pres- 

 ent, although it is often indicated by a furrow. It is then impossible 

 to determine accurately as to its presence, but it has been considered 

 as if it were present. The boundaries of the clypeus are shown very 

 distinctly in Figure i, cl. In the Hepialidae (Fig. 8) there is no 

 clypeo-labral suture present although all the other head sutures are 

 distinct. The clypeus can usually be identified by the presence of the 

 invaginations for the anterior arms of the tentorium, which are asso- 

 ciated with its lateral margins. This sclerite often bears prominent 

 setae, and in the pupae of species whose larvae are borers it has 

 often a distinct cutting plate or ridge. 



