324 



JOHN B. SMITH. 



ordinarily recognized, but also the true labrum and mandibles. This 

 is the only species I have seen in which the mandibles are present, 

 and with this species I shall start, using at once the nomenclature 

 which 1 consider correct, and which 1 hope to establish.* 



In this species there projects from the middle of the front margin 

 of the oral opening (clypeus?), a long, flat, chitinous process, reaching 

 to the end of the mouth organs, supported each side by a rod reach- 

 ing to within the clypeus, and, at the end of this central piece, resting 



Mouth parts of Buffalo gnat. 



on a muscular base supported by the lateral rods, are the minute 

 mandibles, set ol)liquely. They are red-brown, solid, three toothed, 

 and grooved inwardly, in all respects like the mandibles of some 

 Coleoptera and Neuroptera, and absolutely unmistakable. It re- 

 quires a good objective on a well prepared specimen to see them at 

 all, but a one-fifth brings them out fully and clearly. These man- 

 dibular supports are in front of the other mouth parts, and behind 

 them, most prominently, are the parts which I consider the subgalea 



* In the Report of the Entomologist 1886, Dr. Riley's account of the Buffalo gnat is il- 

 lustrated (PI. viii, fig. 2) by a figure of the head, which is very accurate, and in which the 

 mandibles are properly shown. The meaning of the structure was not recognized by either 

 author or artist. 



