THE THOBAX AND ITS APPENDAGES. 

 C 



61 



Fig 26. — Basal elements ot wings of Hymenoptera : A, base of front wing of a sawfly 

 (itycorsia discalor) showin!;' comparatiyely generalized arrangement of veins and 

 axillaries ; B, bases of anterior veins of front wing of a liorntail (Sirex flavicornis) , 

 showing detachment of base of subcostal vein (Sc) from its shaft ; C, corresponding 

 view of anterior veins in front wing of a tarantula-killer (Pepsia sp.), showing com- 

 plete absence of shaft of subcosta, but presence of basal part ISc) fused with base of 

 radius (R) ; D, axillaries of anterior wing of honey bee worker; B, tegula of worker; 

 F base of anterior wing of worker showing absence of shaft of subcosta buf presence 

 of scale (Sc) derived from its base ; G, axillaries of hind wing of worker, the fourth ab- 

 sent in bee ; H, base of hind wing of worker, showing absence of costal and subcostal veins 

 and fusion of bases of subcosta (Sc) and radius (R) into large humeral mass; I, attach- 

 ment of front wing to scutum (Sctz) and scutellum (Sch) of mesotergum ; .T, under view 

 of end of mesoscutellum (8cU) showing attachment of both first (lAx) and fourth 

 axillaries (iiAx) to posterior wing process (PUP), an unusual connection for first axillary. 



