(iOO TERTIARY INSECTS OF NORTH AMERICA. 



Family CECIDOMYID^E Westwood. 



LASIOPTERA Meigen. 



LASIOPTERA KECESSA. 



PI. 5, Figs. 29-31. 

 Lanioptera recessa Scudd., Bull. U. S. Geol. Geogr. Surv. Terr.. Ill, 745-746 (1877). 



A single specimen of ;i minute fly, with the antennae' perfect, the body 

 preserved on a side view, with parts of the legs and the wings folded 

 together over the back, raised from the body. The head is moderately 

 large and appears to be a little narrower than the thorax. The antennae 

 show fourteen joints, without counting the basal joint, and perhaps one or 

 two more next the base,. where the antennae are parted ; the joints are sub- 

 moniliform, slightly broader than long, subequal ; the last joint subconical, 

 twice as long as broad. The wings show a principal vein, which strikes 

 the costa about the middle, and apparently another, striking the costa half- 

 way between this and the tip, a feature which does not accord with the 

 structure of the Cecidomyiche generally ; but the wing at this point is very 

 obscure, so that the appearance may be accidental. The legs are appar- 

 ently about as long as the body and rather slender. 



Length of body, 1.4"' m ; of antennae, 0.6"""; wings, I" 11 ". 



White River, near the Colorado-Utah boundary. One specimen. (W. 

 Denton.) 



LITIIOMYZA Scudder (A/0o?, 



Lilhomyza Scmld., Bull. U. S. Geol. Geogr Surv. Terr., Ill, 746 (1677). 



Ocelli present. Antennae nine-jointed, scarcely longer than the tnorax, 

 the first joint cylindrical, the remainder submonilifonn, ovate, about twice 

 as long as broad, minutely and sparsely pubescent. Wings resembling 

 those of Anarete in neuration, but differing considerably in shape, being- 

 broadest beyond the middle and tapering toward the base. The first longi- 

 tudinal vein extends beyond the middle of the wing ; the auxiliary vein runs 

 close beside the first longitudinal vein, but only half as far, terminating 

 independently; the second longitudinal vein extends to the tip of the wing, 

 curving downward in the distal part of its course : the third longitudinal 

 vein forks as in Anarete, but the independent or fourth longitudinal vein 



