AMERICAN ENTOMOLOGY. 11 



ing at least the twentieth of an inch beyond the thorax : pleura 

 with a dilated blackish-brown line or vitta, beginning at the eye, 

 and including the abdomen above and on each side : feet brown, 

 more or less annulated with pale : venter pale yellowish or testa- 

 ceous. 



Length to tip of wings, nine-twentieths of an inch. 



Obs. I obtained this insect in Georgia and East Florida, where 

 it is not uncommon. 



The upper and right figures of the plate ; natural size and 

 magnified. 



LAPHRIA. Plate VI. 



Generic characters. Body elongated ; wings incumbent : an- 

 tennas divaricating, approximate at base, three-jointed ; third 

 joint inarticulate, obtuse, and destitute of a style : front im- 

 pressed : hypostoma with long rigid hairs": proboscis horizontal, 

 short, without dilated labia : poisers naked : abdomen with seven 

 segments : posterior tibia arquated : tarsi terminated by two nails 

 and two pulvilli. 



Obs. The genus Laphria, of Meigen, is perfectly well distin- 

 guished from its neighboring groups by the above stated traits, 

 and has received the approbation of all recent authors who are 

 willing to keep pace with modern discoveries. The arrangement 

 of the nervures of the wings, particularly of those of the anterior 

 margin, is very similar to that of the wing nervures in the genus 

 Asi'lus, as restricted by the same author ; but the form of the 

 antennae, in this case, at once decides the genus, those of Laphria 

 being simple at their termination, whilst those of Asilus are fur- 

 nished with a very distinct, and generally elongated, setaceous 

 style. 



These insects fly swiftly, and the force with which the wings 

 strike upon the air, produces a loud humming sound. They are 

 predaceous, and pursue with voracity smaller and weaker insects, 

 which they seize, and then alight to suck out their fluids. Many 

 species inhabit the United States. Of these, the thoracicus of 

 Fabricius, and another which I described under the name of ter- 

 gissa, in consequence of the form of body and sounding flight, 

 have been very frequently mistaken for humble-bees, (Bombus.) 



The larvae live, probably, in the earth. 



