134 NORTH AMERICAN DIPTERA. 



mouth-hooklets. The puparium is oval in the smooth cylin- 

 drical forms, or flattened in the others. 



The flies have received but little attention in this country 

 and not a great deal elsewhere. The following table has been 

 mostly compiled from Meade, Schnabl, Rondani and Schiner, 

 with the aid of the table given by Townsend. 



Tegula and antitegula are the terms proposed by Osten 

 Sacken to indicate respectively the lower and upper scales. 



TABLE OF GENERA. 



1. Front in both sexes wide, including at least one-third of the width of 



the head of the male 16 



Front narrow in the male, never more than one-fifth of the width of 

 the head, often holoptic or sub-holoptic. ..... 2 



2. Tegula larger than the antitegula. 3 



Tegula and antitegula of nearly equal size, neither large. . . 14 



3. Front femora of the males with tubercles or emarginations below, or 



otherwise peculiarly constructed ; front tibiae often with emargina- 

 tions; hind femora of ten arcuate ; middle and hind tibiae sometimes 

 with tufts of hairs ; arista always somewhat pubescent, sometimes 

 distinctly plumose; eyes bare (if hairy Odontontha Rond.); abdo- 

 men without macrochaetae ; species black or blue-black in color, 



sometimes pollinose HTDROT^IA Desvoidy. 



Front femora simple in the male 4 



4. Proboscis projecting, horny, the labella slender and pointed, turned 



backward, hook-like; antennae short, arista pubescent, eyes bare; 



moderate- sized, blackish gray species. . . DRYMEIA Meigen. 



Proboscis not horny and hook-like 6 



6. Eyes hairy, more so in the male ; arista plumose ; abdomen not spotted. 



HYETODESIA Rondani. 

 Eyes bare. . . . '' , . . . . . . . 6 



0. Abdomen distinctly spotted ....... 7 



Abdomen not spotted 9 



7. Arista plumose; hypopygium small; blackish gray, yellowish gray or 



reddish yellow species. . . . SPILOGASTER Macquart. 

 Arista bare 8 



8. First posterior cell not coarctate. . . . LIMNOPHORA Desvoidy. 

 First posterior cell coarctate in the margin. LKUCOMELINA Mat-quart. 



