ART. 19 AMERICAN MUSCOID FLIES ALDRICH 21 



Genus CALODEXIA Van der Wulp 



Calodexia Van der Wulp, Biologia, Dipt., vol. 2, 1891, p. 257. — Bbauer and 



Bergbnstamm, Zweif. Ksiis. Mus., pt., 6, 1893, p. 131. — Townsend, Rev. 



Mus. Paul., vol. 15, 1926, p. 219. 

 Oestrogaster Townsend, Proc. U. S. Nat. Mus., vol. 43, 1912, p. 309 ; Ent. News, 



vol. 26, 1915, p. 28 ; Rev. Mus. Paul., vol. 15, 1926, p. 223. 

 Oeslrogastropsis Townsend, Proc. U. S. Nat. Mus., vol. 49, 1915, p. 424 ; Rev. 



MUS. Paul., vol. 15, 1926, p. 223. 

 Ocstroyastrodes Townsend, Proc. U. S. Nat. Mus., vol. 49, 1915, p. 425 ; Rev. 



Mus. Paul., vol. 15, 1926, p. 225. 



The genus Calodexia originally included three species, of which 

 Coquillett (Proc. U. S. Nat. Mus., vol. 37, 1910, p. 517) desig- 

 nated Calodexia, majuscula Van der Wulp as type. He identified a 

 male specimen from Cuernavaca, Mexico, as belonging to this species. 

 I recently sent this specimen to the British Museum, where Major 

 Austen kindly compared it with Van der Wulp's type, and reports 

 it to be correctly identified. 



Townsend proposed all three of his genera on female specimens. 

 The type and sole species of Oestrogaster is Oestrogaster fv/nwsus 

 Townsend; that of Oestrogastropsis is Oestrogastropsis tnexicana 

 Townsend ; and that of Oestrogastrodes is O estrogastrodes simUis 

 Townsend. A male undoubtedly belonging to similis has since been 

 discovered in our material, and we have a female of flampes Schiner ; 

 so there are two species in which both sexes are known. 



In order to elucidate tlie following species of Schiner it is neces- 

 sary to consider the characters of the genotype of Calodexia. 



The type specimen of Calodexia majuscula is a male, and the 

 female has not yet been associated with this species. It must be 

 very much like similis Townsend. In the male the eye is very large, 

 front in profile not prominent, antennal axis short, vibrissal about 

 three-fourths as long; the front is 0.16 of the head width above, 

 widening but little to the antennae and the face still quite narrow; 

 ocellars merely hairs; outer vertical not developed; two large upper 

 frontals reclinate, remainder smaller, decussate, lowest barely at 

 insertion of antennae, which is at middle of ej^e, third antennal 

 joint two and a half times the second, arista thickened at base, sub- 

 plumose for a short distance beyond the thickening, the plumosity 

 rapidly diminishing in length and the apical half practically bare. 

 Parafacials very narrow; vibrissae at oral margin, ridges bare above 

 them and rather flat. Cheek about one-fifteenth of eye height. 

 Palpi and proboscis normal. Infrasquamal hairs present but pale 

 (in our other species usually only one or two hairs present, some- 

 times none). Abdomen slender and pointed; first and second seg- 

 ments with a pair of erect median marginals, third with a marginal 

 row; second and third with a large erect, discal pair; fourth as long 



