The Bumblebees. Various. The Syrphid Flies. 



The Honeybee. Eristalis flavipes. 



i V Megachilelatimana. 



Bombus Virgifiicus (Leaf-cutterbee) 



Helophilus similis. 



Halictus confusus. 



Bombus tern cola. 



Mallota posticata. 



Andnena vicina. 



Halcctus &>Andrena M r-r-t 



are ground bees. V IPjJ 



Bombus Pennsylvanicus Syrpus diversipes. 



BUMBLEBEES, BEES, AND FLIES CONCERNED IN THE 

 CftOSS-FERTlLlZATION OF FLOWERS. 



