250 MANUAL OF NATURAL HISTORY. 



their wings are large, opaque, and membranous ; and 

 there are two subspiral appendages at the base of 

 the fore-legs. These insects have been placed by 

 some between the Beetles and the Earwigs, while 

 others have considered their natural position to be 

 between the Lepidoptera and the Diptera ; they 

 are, indeed, often termed "Wasp-Flies/' and " Wild- 

 Bee Flies." 



X. ORDER. BEE-PARASITES (Strepsiptera). 



Anterior wings in form of short, slender, contorted 

 appendages ; hind-wings very large, folding longitu- 

 dinally, like a fan ; mouth with two slender acute 

 jaws wide apart, and two large 2-jointed palpi ; tarsi 

 2-3 or 4-jointed. Larva apodal, vermiform, with a 

 flattened head ; pupa coarctate, inactive. 

 1. FAMILY. Bee-Parasites (Stylopidae). Antennse 

 of few joints, often furcate or branching, aris- 

 ing from between the eyes ; head distinct, ex- 

 posed; eyes large, lateral, prominent, upon 

 the contracted sides of head ; thorax very 

 large ; body long and narrow ; wings opaque, 

 membranous ; legs moderate, weak, two ante- 

 rior pairs with elongate coxse ; tarsal joints 

 with fleshy cushions beneath, without termi- 

 nal claws. Parasitic on bees and wasps. 



FLIES. 



Although not so numerous in species as some of 

 the other Orders of Insects, with regard to indivi- 



