t^S KANSAS University quarterly. 



scale-like lobe and the broad coalesced collar of some of the moths 

 to the forms in Papilionidce where the lobes are entirely wanting. 

 The scutellum also shows great diversity in form, though a steady 

 development may be traced from the mere dot, scarcely chitenized, 

 found in the familes of Noctoidse, to the higher groups of butterflies, 

 where the chitenized sclerite forms the most conspicuous part of the 

 prothorax. 



The width of the prothorax is noticeably varied, some groups 

 showing a very narrow, compact form with very little membrane, 

 others again being loosely articulated and showing a broad membra- 

 nous surface between the lobes and the mesothorax. 



This variation of form in the sclerites of the prothorax may be 

 reduced to certain families. In the following notes these types are 

 presented and a simple grouping of the species examined is made, 

 based on the different forms of the prothorax found; these types are 

 arranged into groups or classes. 



The first class is based on the special development of the dorsal 

 lobes which almost fill the dorsal space between the head and meso- 

 thorax. The second group is characterized by a greater development 

 of the scutellum. In the third group the prothorax is very narrow 

 and the parts inconspicuous. The fourth class is characterized by 

 scale-like lobes. Under each of these groups a few characteristic 

 species are presented. 



/3. rr ^j^g ^j.gj. group is well represented by 

 Grapia interrogationis (fig. III). A nar- 

 row membranous neck separates the head 

 from the prothorax; the scutum and scu- 

 ScT^ ~^ ^ 1 ^^ tellum are present, the former in the shape 

 of the two large terminal lobes which almost fill the dorsal space, 

 nearly concealing the triangular crescent- shaped scutellum. The 

 lobes are dark brown in color, hollow, the upper surface consisting 

 only of a thin shell; they are covered with short velvety scales, the 

 punctulations, or scale insertions, showing plainly when the scales are 

 brushed away; the anterior part of the scutellum extends forward, 

 forming the deep cleft between the lobes and then expanding into a 

 narrow chitenized band which forms the anterior margin of the pro- 

 thorax, and corresponds to the proscutum. The lateral extremities 

 of the scutellum extend into slender supporting braces beneath the 

 lobes; the scutellum is slightly raised above the membranous surface; 

 it is very narrow just in front of the mesothorax, then broadens 

 abruptly into a narrow collar which articulates with the mesothorax. 

 This ariiculating part is generally concealed by the overlapping meso- 



