306 Hominoxious Arthropods 



i. Dorsocentrals six; last section of Ri+5 with a gentle curve. 



j. Inner dorsocentrals ("acrostichals") wanting; sterno- 



pleurals arranged 1:3. P. cyanicolor, cadaverina, etc. 



Europe and America Pyrellia R. D. 



jj. Inner dorsocentrals ("acrostichals") present; sterno- 

 pleurals arranged 1:2. E. latreillii. North America. 



Eumesembrina Town. 



ii. Dorsocentrals five; inner dorsocentrals present; last 

 section of Ri+5 with a rounded angle; sternopleurals 

 arranged 1:2. P. cornicina Europe and America. 



(Pseudopyrellia Girsch.) Orthellia R. D. 



ee. Middle tibia without a prominent bristle on the inner surface beyond 

 the middle. 



166. Pycnosoma marginale. (x4.) After Graham-Smith. 



f. Squamula thoracalis broadened mesad and caudad as far as the 



scutellum. 



g. Sternopleural macrochastae arranged in an equilateral triangle; 



front of both sexes broad; genae bare; dorsocentrals six, 



small; wing not rilled. (To COENOSIN.E). Atherigona Rdi. 



gg. Sternopleural macrochaetae when three are present, arranged 



in a right triangle, 

 h. Last section of RH-S with a more or less rounded angle 



(fig. 163!). 



i. Eyes of the male pilose or pubescent, of the female nearly 

 bare; m-cu crossvein usually at or proximad of the mid- 

 distance between the r-m crossvein and the bend of 



R4+5. P. ( = Placomyia R. D.) vitripennis 



Plaxemyia R. D. 



ii. Eyes bare; the m-cu crossvein always nearer to the bend of 



Ri+5 than to the r-m crossvein. 



j. Apex of the proboscis when extended reveals a circlet of 



stout chitinous teeth. P. insignis Austen, of India, 



bites both man and animals. ( = Pristirhynchomyia) 



Philaematomyia Austen 



