BOMBYLIID^E. 213 



flower flies, feeding upon the pollen and honey within 

 the blossoms, extracted by aid of their often long probos- 

 cis. The larvae of species of Aphcebantus and Systcechus, 

 occurring in western America, are found in the egg-pods 

 of the locust, Caloptenus spietus. 'The larvae begin to 

 transform themselves into the pupa state early in the 

 summer, and the pupa pushes itself half way out of the 

 ground in order to disclose the fly. They continue to 

 issue during the summer months. Aphcebantus is first 

 observed as a yellowish white grub, about half an inch 

 long when extended, it being usually curved so that the 

 head and tail nearly meet. It is usually found in a case 

 of locust eggs which it has devoured, pushing the empty 

 shells aside, and at last occupying the space where were 

 twenty-one to thirty-six eggs. Often it is found in a lit- 

 tle space below a number of egg-cases, as though it had 

 feasted off the contents of several nests' (Riley). The 

 larvae of Anthrax have been found parasitic upon Mega- 

 chile, Osmia, Odynerus, Mamestra, Noctua and Agrotis ; 

 those of Spogostylum upon Pelop<zus, Megachile, Cemonus, 

 Osmia, Cicindela and Calicodoma; those of Bombylius upon 

 Andrena and Collettes; those of Toxophora upon Eumenes; 

 those of Callostoma in the egg-cases of Caloptenus italics; 

 those of Systropus upon Limacodes. 



Fig. 86. Bombyliidae. i, Anthrax, wing; 2, Hyperalonia, wing; 

 3, Exoprosopd) wing; 4, Exoprosopa, hind claw; 5, Spogostylum, 

 antenna; 6, Anthrax, antenna; 7, 8, Exoprosopa, antennae; 9, Bom- 

 bylius, wing; 10, Pantarbes, wing; n, Pantarbes, antenna, 12, Sys- 

 toechus, wing; 13, Lordotus, wing; 14, Lordotus, antenna; 15, Phthi- 

 ria, wing; 16, Phthiria, antenna; 17, Sparnopolius, antenna; 18, 

 Geron, w T ing; 19, 20, Geron, antennae; 21, Toxophora, wing; 22, Tox- 

 ophora, antenna; 23, Systropns, wing; 24, Systropus, antenna; 25, 

 Mythicomyia, wing; 26, Mythicomyia, antenna. 



21 



