744 



PROCEEDINGS OF THE NA TIONAL MUSEUM. 



covered by observing the behavior of the medial and cubital branches 

 just after their separation. Just bcvond the arculus veins J/i+g and 

 M. separate by arching in t)pposite directions, forming a symmetrical 

 fork. At the end of the quadrangle vein J/^ arches forward, vein 

 Cu^^ sometimes arching with it, and vein 6^1*2 arches backward, the 

 two thus becoming set in opposing positions. Vein Cu^ remains 

 simpU\ 



Fl(i. 82. — WlNC OF Pt<ruiliipli:tii t:}/^ 



Throughout the group the stigma is well developed. In the space 

 between veins J/j and JI^ the longest of the sectors occupies an inter- 

 mediate position, with shorter sectors on either side of it. The South 

 American Cyanocliar'ix (Plate LI, fig. 3) and D'lcterian parallel the 

 next following group in the fusion o-f vein M^_^ with the radius bej^ond 

 the arculus, but in general the group is wholly lacking in those 

 peculiar developments that characterize the two next groups. 



Anisopleura, Epallage (Plate LI, fig. 2), Bayadera^ CyanocharisiPhiiQ 



Fig. 33.— Ba.se of fohewinu and a bit of hindwing of Rhinocypha sp? o, oblique vein that ■ 



WORKS THE I'OINT OF SEPARATION OF THE TRACHEA OF THE RADIAL SECTOR. 



LI, fig. 3), Dlphlehia, and IViiloganga (fig. 44) illustrate a tendency 

 toward the reduction of the base of the wing, and toward a consider- 

 able degree of vein difiercntiation throughout the membrane. The 

 general result is analogous to that arrived at in the Agrionina\ 

 discussed below. 



VcKtalina?.. — In all this extensive group the media descends the 

 arculus and departs from it in a line that is continued directly by\i 

 vein J/",, Avhilc \em M^+o arches strongly from its anterior side. The'j 



