LEPIDOPTERA OF NEW YORK AND NEIGHBORING STATES 



21 



off behind, and there is a slight notch in the upper front side, where 

 the antenna arises. Often there are minute straight hairs arising 



between the facets, in 

 which case the eye is called 

 hairy (fig. 14). A lashed 

 eye is one in which bristles 

 arise around the edge and 

 curve over it (fig. 15), 

 especially in front below 

 the antennae, and behind. 

 The facets are usually finer 

 and more numerous in noc- 

 turnal forms. 



The simple eyes, or ocelli 

 (fig. 3), when present, lie 



FIG. 13. FRONTAL VIEW OF LOWER PART OF HEAD, behind the rQ()t Q f the fln . 

 DIAGRAMMATIC m i 



tenn83. They vary in size 



and in distance from thr eye, and are often absent, as in all butterflies. 



The portion of the head between the eyes in front is the front, called 



clypeus or clypeus posterior by some entomologists (figs. 3, 13), and 



Epipharynx 



13 



FlG. 14. HAIRY EYE 



(HIGH MAGNIFICA- 

 TION) 



15 



FlG. 15. LASHED EYE (MODER- 

 ATE MAGNIFICATION) 



the sharp projecting ridge along its lower boundary is the true clypeus. 

 The head between the eyes above is the vertex; and the back of the 

 head, behind the eyes and ocelli, is the occiput (fig. 3). 



The labrum of the imago (fig. 13) is a three-lobed structure. The 

 middle lobe merely closes the space between the bases of the maxillae; 

 the two lateral lobes are the pilifers, and project across the base of 

 the tongue, each bearing a tuft or row of bristles, which provide 

 important characters in the classification of the Sphingidaa. 



"The mandibles are almost always rudimentary or absent, difficult to 

 find, and unimportant (fig. 49). In Epimartyria alone there are regu- 

 lar biting mandibles ; but in a dried specimen they are usually difficult 

 to see without dissection. 



