1921] Vespa arciica, a parasite of Vespa diahoUca 141 



of V. gennanica and communis, in which the mother queen is often 

 found as late as the hist of September or early October. 



Perhaps the diabolica queen may resemble the crabro queen in 

 her tendency to desert an incipient nest and found another, or 

 perhaps, as a rule, she may desert her nest as soon as it is invaded 

 by an arctica queen. That she is short-lived, like the queen of 

 medm, seems to be indicated by the following observations on 

 uninfested nests : 



July 21, the senior author asphyxiated a diaholica colony which 

 was nesting very near the ground at the base of a cluster of golden- 

 rods in a deserted pasture. The nest was well-developed, with two 

 large combs and a very small, four-celled third comb. There were 

 76 workers but no queen, although her presence might have been 

 expected, since the colony was asphyxiated after dark. 



August 27, the senior author found depending from the ceiling 

 of a porch a small abandoned diabolica nest. It had only a single 

 small comb, about 3.5 cm. in diameter, containing some dead 

 worker pupae and small larvae. A similar deserted nest was found 

 earlier in the season attached to the limb of a tree. 



Also on August 27 a large, well-developed diaholicu nest was 

 found under the roof of a water-tank. Two living workers were 

 still clinging to the involucre, which contained three well-developed 

 combs. There were a few living worker pupa3 in the combs and a 

 number of dead workers that had fallen from the nest. The males 

 and virgin females had departed, so that the colony must have 

 completed its development several days and possibly a few weeks 

 before the first of September. 



Of eight diabolica nests taken by the Junior author before August 

 4, on the grounds of the Arnold Arboretum, only one contained an 

 old queen, although in each case care was taken to secure the entire 

 colony. 



A flourishing colony of V. diabolica comprising 200 to 250 

 workers, also without a queen, was taken August 10. The appar- 

 ently exclusive emergence of males from this colony, as a result 

 of which there were scarcely 25 workers left in the nest by Sep- 



