THE GENUS DENDKOCTONUS. 



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junction with the radius, which appears to form the broad chitinous 

 costal area to near the apex, with branch 2 as a distinct Tein. 



Suhcosta. — The subcosta is the principal vein of the wing. It gives 

 rigidity to the base, and with the head of the costa forms the articu- 



lating head. It is broadest where it is joined by the costa, and is 

 strongly narrowed to its junction with the radius. 



Radius. — The radius is an important vein in giving additional rigid- 

 ity to the median, distal, and costal areas and in forming the folding 



