SUBFAMILY MESEMBRINELLINAE 61 
or near middle of eye with head in profile; bases approximate; 
third segment of antenna reaching nearly to vibrissa; arista 
nearly twice as long as third segment, penultimate segment 
short, terminal segment elongate, thickened only at base and 
uniformly tapering to apex, with long ciliation above and below; 
back of head flat or but slightly rounded in profile. 
Thorax with propleuron bare; presupraalar bristle one; no- 
topleural bristles two; prosternum narrowed posteriorly, widen- 
ing anteriorly, setose; postalar declivity with tuft of hair in 
center; sclerites at wing-base with only preepaulet setose; tym- 
panic pit bare; greater ampulla slightly reniform posteriorly; 
postalar bristles two, one weak; postdorsocentral bristles three; 
intrapostalar, intrapostsupraalar and intrapostsutural bristles 
absent; postintraalar bristles two; postsupraalar bristles three; 
spiracles large; scutellum with under surface finely setose, the 
setae short, and with one discal and one apical bristle. 
Legs elongate and slender; hind coxa setose posteriorly; fore 
tibia with one posterior bristle near apical third; middle tibia 
with one anterodorsal bristle near apical third and one ventral 
bristle near apical third; hind tibia with one anteroventral 
bristle near apical fourth and two posterodorsal bristles toward 
base. 
Wing without costal spine; subcostal sclerite with fine pube- 
scence; remigium bare below (ciliate posteriorly above in Mes- 
embolia) ; only third vein with setae; bend in fourth vein widely 
rounded; anterior cross vein at or near middle of second section 
of fourth vein; upper squamal lobe small, bare, rounded; lower 
squamal lobe of medium size, ovate, bare. 
Abdomen with tergites not overlapping sternites, the ventral 
membrane usually widely exposed in both sexes; first and sec- 
ond segments without dorsal bristles; fourth segment often with 
discal and usually with strong marginal bristles. 
Genital sezments of male large, terminal, globose, and obvious 
in repose; of female, not in form of extensile ovipositor. 
MORPHOLOGY OF INTERNAL SEXUAL STRUCTURES. 
It has been stated previously that the Mesembrinellinae are 
aberrant in the Calliphoridae. The reproductive habits, the 
structures of the internal organs of reproduction, and certain 
details of external morphology in the female are not as in typical 
blowflies. However, these flies are treated here as a subfamily 
of Calliphoridae because the male genital structure is very 
similar to that found in typical Calliphoridae, and the adult fly 
possesses most of the characters considered calliphorine. 
