INSECT ACTORS 115 



Certain of the Diptera mimic the Hymenop- 

 tera. The Surphus flies are extremely wasp- 

 like with their gaily striped yellow and black 

 bodies, and a great many people mistake them for 

 the more aggressive insect. The Volucella also 

 mimic wasps and bees in their outward appear- 

 ance : one member ;of this family, Volucella 

 bombylans, precisely resembles a small, hairy 

 bumble-bee. The particular advantage this fly 

 gains by the similarity is that thus disguised 

 it can enter the nests of the bees and deposit 

 its eggs without being observed, and so provide 

 food for its young, who, when they emerge from 

 the eggs, feed upon the larva of the bumble-bees. 

 Several other species of Diptera mimic bees, 

 most of them being parasitic in the larval stage, 

 and living in the nests of solitary bees. 



Several species of Coleoptera have become 

 adepts in passing themselves off as belonging 

 to entirely different Orders of insect. In the 

 tropics many of the Longicorns appear in the 

 guise of wasps, bees or ants, in order to escape 

 the persecution of insectivorous birds, who are 

 particularly fond of this type of beetle. The wing- 

 cases of the Longicorns that mimic hymenop- 

 terous insects have become much shortened, 

 so that the membranous wings have freer play, 

 and the yellow banded bodies are exposed. In 

 some species the abdomen Js constricted at the 

 base into a narrow wasp-like waist, and others 

 that mimic bees have tufts on the hind legs to 

 represent the pollen-gathering tibea of the 

 hymenopterous insect. 



Some of the Coleoptera are themselves 



