376 University of Calif ontia Publications [Entomology 



side of the cell M.J always less than 180°. This is the case in other 

 Masaridinae {Ceramioides, Ceramms), and in Gayellinae. In Eupa- 

 ragiinae the angle is about 125°, the upper part of the cell M, being 

 produced apicad to a point closer to the cell R- (measured along 

 M3^.4) than the length of the cephalic section of Mo, a condition not 

 obtaining elsewhere in the Vespidae, and giving to the wing of Eupa- 

 ragia a peculiar facies. In the Gayellinae the condition in this region 

 of the wing is almost identical with that found in Ceramoides — 

 M^ + Cui being a little longer than in that genus. 



In Euparagiinae, apart from the prolongation of the upper apical 

 angle of the cell M,, the condition of this region of the wing is more 

 primitive than obtains elsewhere. M4 -|- Cu^ is not abnormally far 

 basad in the wing, is opposite m-cu and two-thirds as long as that vein, 

 so that the cell Cu -|- Cu^ is wide at apex. By reason of the fact that 

 the veins M^ -f- Cu^ and M, approach each other, the caudal margin 

 of the cell M, is scarcely longer than the basal width of the cell, a 

 condition very far from being the case in any other Vespidae. 



THE RADIAL REGION OF THE FOREWING 



The most primitive condition of the radial region of the forewing 

 occurs in Euparagiinae, Gayellinae, and Raphiglossinae, in which cells 

 R4 and R- are distinct, receiving, respectively, veins M2 and M3, j. 



In Zethinae, Eumeninae, Stenogastrinae, Epiponinae, Rhopalidii- 

 nae, Polistinae, and Vespinae the base of the free part of the vein M, 

 has migrated basad toward Mg^^ until they both are opposite the cell R-. 



In Masaridinae these two veins are in the position just indicated, or 

 in an intermediate position, but an additional step is found in the loss 

 of the vein R-, throwing the cells R4 and R- together. 



In the Euparagiinae, Masaridinae, and Gayellinae an appendiculate 

 cell is always present, and in the first two of these subfamilies the cell 

 2d Ri -{- R. does not extend farther toward the wing apex than does 

 the cell R4. In the few genera in wdiich this is not the case both cells, 

 and, in Gayellinae and in most of the genera of Vespidae with plaited 

 wings, the cell 2d R^ + ^i extend closer to the wing apex than they do 

 in Masaridinae. In Stenogastrinae this condition is carried to an 

 extreme. 



In the Vespidae with folded wings an appendiculate cell is rather 

 exceptional. 



