308 



Hominoxious Arthropods 



at rest. Cluster flies. P. rudis and related species, widely 



distributed Pollenia R. D.* 



gg. Body metallic blue or green. Eastern Hemisphere. 



h. Vibrissal angle placed very high above the oral margin; a 

 carina between the antennae; outer posthumeral wanting; 



anterior intraalar present. T. viridaurea. Java 



Thelychata Br. 



167. Horn fly. (a) egg; (&) larva; (c) puparium; (d) adult. (x4). Bureau of Entomology 



hh. Vibrissal angle moderately high above the oral margin; 

 carina small or wanting; no post humeral macrochaeta; 

 lower squamae hairy above. (=Paracompsomyia 



Hough) (fig. 166) Pycnosoma Br. 



ff . Genae bare. S. terminata. Eastern Hemisphere 



Strongyloneura Bigot 



ee. Sternopleurals arranged 2:1. 



f. Body metallic green or blue, with gray stripes; genae hairy to the 

 lower margin; post numerals often wanting; lower squamae bare 



above. ( = Compsomyia Rdi.) Chrysomyia R. D. 



g. With one or two orbitals; height of bucca less than half the 



height of the eye. South and east U. S. (fig. 107) 



C . marcellaria 



gg. No orbitals; height of bucca about a third less than height of 

 eye. West U. S C. wheekri Hough 



*Nitellia, usually included in this genus has the apical cell petiolate. Apollenia Bezzi, has 

 recently been separated from Pollenia to contain the species P. nudiuscula. Both genera belong 

 to the Eastern hemisphere. 



