TAXONOMY OF MUSCOIDEAN FLIES — TOWNSEND 23 



[Before ptilinal suture] 



1) Ptilinal area (area enclosed .by ptilinal suture = facial depression of 

 descriptions plus antennal somite plus lunula; front of Berlese) of what form, 

 width above and below compared with adjacent parts of parafacials and para- 

 frontals. 



1) Facial plate (clypeus of Brauer and von Bergenstamm; face, facial 

 plate, mcsofacial plate of Lowne plus epistoma; facial depression of authors, 

 prefront of Berlese, transverse impression of face of Hough — in each case 

 minus facialia and plus epistoma) produced and swollen in middle like the 

 bridge of the nose, merely swollen nose-like below, tube-like, projecting for- 

 ward in profile below, flat, even, elongate, reaching almost to lower margin of 

 head, extending obliquely downward and posteriorly, reaching straight down 

 between vibissal angles, widened below same ; shortened in front view, ending 

 high above lower margin of head ; widened below, oval, triangular, compara- 

 tive width above and below, narrowed high or low by the facialia or by the 

 vibrissal angles. 



1) Mesofacial plate (do. of Lowne; facial plate minus epistoma). 



1) Foss.E of facial plate [fovea plus foveal sinuses) long, short, wide, 

 narrow, deep, shallow, curved, straight. 



2) FovE-E (fovece of Robineau-Desvoidy ; antennal grooves of descriptions ; 

 simply depressions in the facial plate) deep, shallow, elongate, short, double, 

 single, and confluent. 



1) Foveal sinuses (more or less linear grooves which in certain cases 

 form outlets of the fovea: anteriorly) linear, widened, deep, faint, convergent, 

 divergent, etc. 



2) Facial carina (keel of descriptions) present, absent, developed only 

 above, weak, strong, high, sharp, knife-like, thin, thick, flattened, rounded, 

 widened, canaliculate or furrowed on its median line, or simple. 



1) Facialia (facialia of Robineau-Desvoidy and Osten-Sacken; facial 

 ridges of descriptions; facial edges of paracephalon of Lowne; Vibrissenleisten 

 of Brauer and von Bergenstamm; vibrissal ridges of Hough) parallel, gradually 

 convergent below, short, long, bare, ciliate, narrow, sharp, widened, flattened, 

 divergent, or absent. 



1) Facial bristles (those on facialia; Vibrissen of Brauer and von Ber- 

 genstamm) ascending less than half way on facialia, or half way, or to point 

 opposite lowest frontals, or nearly or quite to base of antennas ; in one or two 

 rows, bushy, in irregular position, short, weak, long, represented by many 

 rows of fine hairs, normal with hairs among the bristles, only one or two 

 above vibrissa?, or wholly absent. 



1) Vibrissal angles (Vibrissenecken of Brauer and von Bergenstamm; 

 angles or corners where the facialia and peristomalia meet) pronounced, 

 weak, high above the lower margin of head, set low, rounded, sharp, or absent. 



2) Vibrissal papillae (Vibrissemmilste of Brauer and von Bergenstamm; 

 sometimes present at vibrissal angles) prominent, pronounced, flattened, weak, 

 inconspicuous, or absent. 



1) Vibrissa (the two longest or strongest bristles, one at each vibrissal 

 angle; Vibrissen of Brauer and von Bergenstamm) approximated, widely 

 separated ; their insertion on, close to, well removed from the oral margin, or 

 on, close to the under margin of the head, or on the upper edge of the oral 

 margin when this is turned up and broadened, or on or near end of facial plate, 



