456 NORTH AMERICAN DIPTERA 



367. Head about as long as high Masistylum Brauer & Bergenstamm 



Head much higher than long Phantasiomyia Townsend 



368. Cheeks less than half the eye-height in width 369 



Cheeks nearly as wide as the eye-height (28, 29, 144). 



Euryceromyia Townsend 



369. Palpi normal 370 



Palpi very greatly swollen, unusually large Lispidea Coquillett 



370. Third antennal segment more than twice as long as wide. 



Clausicella Rondani 

 Third antennal segment less than twice as long as wide (16). 



Plectops Coquillett 



371. No appendage or fold at bend of fourth vein, if an adventitious ap- 



pendage is present it is not continued in the same line as the fourth 



vein 385 



An appendage or distinct fold at the bend of the fourth vein, the 

 appendage continued in almost the same line as the preceding sec- 

 tion of the vein 372 



372. Posterior pair of presutural acrostical bristles situated very close to 



the suture and much behind the posterior pair of presutural dorso- 



centrals 373 



Posterior pair of presutural acrosticals almost in a line with the 

 posterior presutural dorsocentrals or in front of them 374 



373. Frontal bristles extending almost to the middle of the third antennal 



segment; genital opening not slit-like Exorista Meigen 



Frontals descending but little below the base of the third antennal 

 segment; genital opening rather slit-like (9) . . *Tachinomyia Townsend 



374. Arista with long rays 378 



Arista pubescent or bare 375 



375. Intermediate abdominal segments without discals 370 



Intermediate abdominal segments with paired discals; fourth vein 



with very short appendage, or none; face never carinate. 



•fDexodes Brauer & Bergcmstamm 



376. Cheeks not over one-third as wide as the eye-height 377 



Cheeks about half as wide as the eye-height Ochrocera Townsend 



377. Abdomen long and narrow; ultimate section of proboscis elongate. 



Catenophrys Townsend 

 Abdomen oval; proboscis short and robust JNeophryxe Townsend 



378. Face not strongly carinate, more or less carinate in the middle above. 381 

 Facial carina strongly developed and reaching to the clypeal region. .379 



379. Prosternum bare 380 



Presternum with two pairs of bristles Trichoduropsis Townsend 



* Curran, 1926, Tr. Roy. Soc. Canada, Sec. V. p. 168. 

 t Curran, 1927, Can. Ent., lix, p. 20. 



:•: This genus was described from specimens reared in Massachusetts from material originat- 

 ing in Japan. 



