592 AN INTRODUCTION TO ENTOMOLOGY 



LLL. Palpi upturned, with acuminate third segment, 



often exceeding the vertex; maxillary palpi of folded 



type but very minute or obsolete. 



M. Vein Ri of the fore wings more than twice as 



long as vein R2 and arising before the middle of the 



discal cell. p. 629 Cosmopterygid^ 



MM. Vein Ri of the fore wings but little longer than 

 vein R2, and arising beyond the middle of the discal 



cell. p. 631 SCYTHRIDIDyE 



Suborder JUGATE 



This suborder includes those Lepidoptera in w^hich the posterior 

 lobe of the fore wing is specialized so as to form an organ which unites 

 the fore and hind wings ; and in which the venation of the hind wings 

 is similar to that of the fore wings. 



The Jugatse includes the more generalized members of the order Lepidoptera 

 now living, those which are believed to resemble most closely the primitive in- 

 sects from which in ancient times the Lepidoptera were evolved. In fact the first 

 two families here included in the Jugatae may be of even more ancient origin, repre- 

 senting one or two lines of evolution distinct from the lepidopterous stem. 



Several writers have called attention to indications of trichopterous affinities 

 of the two families in question; and a study of the wing- venation of these in- 

 sects led me to believe that they are more closely allied to the Trichoptera than to 

 the Lepidoptera. For this reason, in "The Wings of Insects" I classed them with 

 the Trichoptera. 



Although these indications of trichopterous affinities are undoubted, it appears 

 that the view now generally held is that, while they show a close community of 

 descent of the Trichoptera and the Lepidoptera, they are not sufficient to warrant 

 the removal of the families in question from the Lepidoptera. I, therefore, in- 

 clude them, provisionsally, in this order in the following account. For a detailed 

 discussion of this subject, see Braun ('19) and Crampton ('20 b). 



The suborder Jugatse, as now more commonly limited, in- 

 cludes several families, representatives of three of which have been 

 found in America; these are the Micropterygidae, the Eriocraniidge, 

 and the Hepialidce. 



The members of the first two of these families diflFer greatly in 

 appearance from those of the third family, being very small moths 

 which resemble the small tineids in size and appearance; our largest 

 species has a wing expanse of from 12 to 14 mm. For this reason 

 they may be known as the Microjugatas. They have also been termed 

 the Jugo-frenata, because, in addition to having the posterior lobe of 

 the fore wing specialized so as to form an organ which serves in 

 uniting the fore and hind wings, there is also a bunch of bristles borne 

 by the hind wing near the humeral angle, which resembles a frenulimi ; 

 these bristles, however, are not homologous with the frenulum, but 

 are the costal spines described on page 575. On the other hand, the 

 members of the third family are mostly large moths; many of them 

 are very large ; and the smaller species have a wing-expanse of 2 5 mm. 

 The members of this family may be known as the Macrojugatas. 



Family MICROPTERYGID.^ 



The Mandibulate Jugates 

 The members of this family are small insects which resemble 

 tineid moths in general appearance. As with other members of the 



