2 PROCEEDINGS OP THE NATIONAX, MUSEUM. vol.65 



frons as described above. Other characters that may be mentioned 

 are : Orbital bristle 1 ; and dorsocentrals, two pairs. The family is 

 more closely related to Ortalidae than to Sapromyzidae. 



The Pallopteridae resemble the Lonchaeidae in having the ovi- 

 positor elongate sword-shaped, but the frons is transverse at its an- 

 terior margin as in Sapromyzidae, and the frontal luniile is con- 

 cealed; the propleural bristle is absent or present; stigmatal bristle 

 absent, or present but weak; sixth wing vein traceable to margin, 

 straight; preapical dorsal tibial bristle absent; each orbit with one 

 bristle as in Lonchaeidae ; propleura bare. 



The Sapromyzidae have no stigmatal bristle, and in this respect 

 agree with many allied families, but the propleura are bare ; the sixth 

 wing vein is shorter than the seventh ; the posterior basal cell of wing 

 is very small and is not prolonged at apex ; usually one or more pairs 

 of the tibiae have a distinct preapical bristle, and both the meso- 

 pleura (except in Periscelis) and sternopleura have one or more 

 strong bristles. Each orbit in American genera (except Periscelis) 

 with two bristles ; the frontal lunule is concealed ; the anterior mar- 

 gin of frons transverse ; postvertical bristles convergent or cruciate ; 

 propleural bristle present. The ovipositor is never sword-shaped. 



Our only representative of the Pallopteridae occurs in humid, well- 

 shaded localities; the Sapromyzidae, on the other hand, are rather 

 inclinded to sit in the sun and they are sometimes attracted to flowers. 

 The immature stages of these f amiles are practically unknown. The 

 larvae of a number of Lonchaeidae are known, however, and they 

 live in sappy places under bark or in decaying vegetation where 

 they are predaceous ; the adults are of more random occurrence than 

 those of the other familes here treated but agree with them in being 

 attracted to light. 



The number of species in the present list compared to that of the 

 New Jersey State List of Insects ^ is : 



District 



Lonchaeidae. _ 

 Pallopte^idae_ 

 Sapromyzidae. 



Of the 60 species here listed, 19 (indicated in text by asterisks) 

 were originally described from material derived wholly or in part 

 from our region. Thirty- two of the species have been collected on 

 Plummer Island, Md., headquarters of the Washington Biologists' 

 Field Club, and 17 others in adjacent parts of the Potomac River 



lAnn. Rep. State Mus., (1909) 1910, Diptera by C. W. Johnson. 



