32 PROCEEDINGS OF THE NATIONAL MUSEUM vol.78 



Townsend's name of piperi is retained for Coquillett's schizurae. 

 Aldrich failed to note that schizurae (Townsend) 1891 is also an 

 Achaetoneura, hence he regarded the new name piperi unnecessary. 



16. ACHAETONEURA RILEYI (Williston) 



Masicera rileyi Williston, Sciiclder's Butterflies of New England, vol. 3, p. 

 1924, pi. 89, figs. 22-24, 1889. 



Front of male at vertex 0.31 to 0.29, at widest part 0.41 to 0.39, in 

 female at vertex 0.32 to 0.33, at widest part 0.40 to 0.41 the head width. 

 In quite a few specimens there appears to be little or no difference in 

 the width of the front as regards sex. Front and face cinereous; 

 inner eye margins moderately divergent. Antennae in both sexes 

 about three-fourths the length of the face; second joint yellowish, a 

 little less than one-half the length of the third, the latter black; 

 bucca one-fifth the head height. 



Thorax black, gray pollinose; the chaetotaxy as in frenchii; scu- 

 tellum with four pairs of marginal bristles besides the apical ones, 

 the bristles nearest the suture and those nearest the apical pair 

 strongest. 



Abdomen brownish in most part with a well-marked black dorsal 

 vitta. Bases of last three segments with narrow borders of light 

 grayish pollen. Usually the first and second segments are destitute 

 of macrochaetae but sometimes a weak pair are present on seg- 

 ment 2. 



Mid tibiae with one strong bristle on the outer front side near 

 middle. Hind tibiae evenly ciliated without a longer bristle. 



Wing venation normal. 



Length, 7-8 mm. 



Redescribed from a number of specimens of both sexes at the 

 United States National Museum. 



The species was originally described by Williston from material 

 (both sexes) reared by C. W. Riley, from Papillo tlioas Linnaeus, 

 locality not given. 



Coquillett '^f had considered rileyi as a synonym of irrequieta Walker 

 but later, in his manuscript notes, regarded the two as distinct, 

 Aldrich-^ also regarded them as distinct. At the United States 

 National Museum the species was placed in Thysanomyia Brauer and 

 Bergenstamm, presumably by Townsend, but as the type of that 

 genus, Brachycoma fbrnhriata v. d. Wulp, has the vibrissae well above 

 the oral margin and other differences also, rileyi certainly can not be 

 of that genus and is best regarded as an Achaefoneura. 



=" Revision N. A. Tachinidae, p. 108, 1897. 

 s«Cat. Dipt, p. 463, 1905. 



