J. K. MALLOCH 313 



Hylemyia piloseta sp. n. 



Male. — Agrees in color with marginelln. 



Eyes separated by distinctly more than the width across posterior ocelli; 

 arista with the longest hairs not as long as basal diameter of arista; parafacial 

 in profile almost as wide as height of cheek. The armature of fifth abdominal 

 sternitc is similar to that of margimda and sinnilamellata (fig. 6), but the 

 hypopygium is distinctly different (fig. 12). The chaetotaxy of the legs is 

 similar to that of the other members of this group, but the femoral bristles 

 of mid and hind legs are longer and stronger on the ventral surface and form 

 more nearly complete series than in the others. The outer cross-vein is more 

 erect and much straighter than in any of the other species, especially margin- 

 nata. Length, 7 mm. 



Type.— d"; Corvallis, Oregon, April 26, 1908, [Coll. Illinois]. 

 Paratypes. — 1 cf , Mary's River, Oregon, [Coll. Illinois]; Troy, 

 Idaho, May 31, 1908. 



Type and one paratype in the collection of Illinois State Nat- 

 ural History Survey, one parat^'pe in the Academy of Natural 

 Sciences of Philadelphia. 



There are several more species closely allied to the foregoing in 

 North America, some of which I have before me now. The 

 species described by Johannsen as Hammomyia setigera is a 

 Hylemyia very closely related to, if not identical with, marginata 

 Stein. I have not seen setigera, but the description agrees more 

 closely with marginata than with any species known to me and 

 the hjqiopygia are ver\' much alike. 



Hylemyia mimetica sp. n. 



Male. — Black, shining. Face, orbits, and cheeks with .slight whitish prui- 

 nescence. Thoracic dorsum indistinctly trivittate. Abdomen with the dor- 

 sum very conspicuously brownish gray pruinescent, when viewed from be- 

 hind with a broad black central line, when viewed from above and laterally 

 the segments appear to be blackened on anterior and posterior margins; 

 hypopygium glossy black. Legs black. Wings subfuscous. Calj-ptra white. 

 Halteres yellow. 



Eyes separated by a little more than width of anterior ocellus; parafacial 

 in profile nearly as wide as third antennal joint at base of antennae, becoming 

 much narrower below; cheek about one-fifth as high as eye; arista with the 

 longest hairs slightly longer than its basal diameter. Thorax with three 

 pairs of moderately strong presutural acrostichals, between which there are 

 no weak hairs. Abdomen narrow, slightly tapered to apex, depressed; hypo- 

 pygium small; fifth sternite with two narrow elongate proce.sses, which are 

 armed with soft erect hairs along their inner margins and to middle of disc, 

 the hairs longer at bases of processes, but nowhere bristly. Fore tibia with 



TRAN.S. AM. EXT. SOC, .XLIV. 



