191 



Family Bombyliidse — The Bee Flies 



Small to moderately large flies, often with pictured wings and 

 frequently clothed with abundant, delicate hairs or scales which are 

 easily abraded, rarely with conspicuous bristles. 



Head narrower than or as broad as the thorax, more or less hemis- 

 pherical in shape; usually closely applied to the thorax. Face variable, 

 usually short, often prominent below. Eyes large, often contiguous in 

 the male, rarel}' so in the female. Antennae three-segmented, porrect, 

 rarely long, usually of moderate length, sometimes small; third segment 

 simple; style usually small, never more than two-segmented, some- 

 times absent. Ocelli present. Proboscis sometimes short and with 

 broad labellse, usually more or less elongate and projecting from the 

 oral cavit}'. Thorax convex above, sometimes strongly so, usually with 

 bristles. Abdomen composed of six to eight segments, slender in a few 

 genera, usually depressed but often cylindrical and more or less taper- 

 ing. Legs moderately long and weak, usually with short, weak bristles 

 or spines; pulvilli sometimes rudimentary, the empodia usually absent. 

 SquamsB small. Wings often pictured; two to four submarginal cells 

 (rarely with only one) discal cell almost always present (absent in 

 some genera occurring outside North America) ; anal cell closed or 

 narrowly open. 



The family comprises almost two thousand described species and 

 occurs throughout the world, being most abundantly represented in the 

 tropical and subtropical regions. They are found particularly in warm 

 spots, a relatively small numl)er occurring in woods, and I have taken 

 none in heavy shade. They like the warmest time of the day and most 

 of them rest upon the dry soil, dried grass or upon grass in sandy 

 places when not visiting flowers. Some species are found mostly at 

 bloom, others but rarely. They are (mostly) great hoverers and gen- 

 erallj^ very rapid fliers although they frequently fly but a short dis- 

 tance when disturbed. In the tropics I found many species in sunny 

 places near the trees at the edge of the beach and along the trails in 

 the forest, and similar places are productive in the north. Many of 

 the species buzz persistently when captured. 



Taxonomically the family is (in North America) in almost hope- 

 less condition, the literature being extremely scattered. Only a few 

 of the described species have been properly figured and without illus- 

 trations and usable keys the student is greatly handicapped. In addi- 

 tion to this unfortunate state of affairs the flies themselves present an 

 obstacle, as the hairs are easily abraded and great care must be exer- 

 cised in collecting them. Only a very few specimens should be placed 



