68 DIPTERA OF NORTH AMERICA. [PART II. 



second joint of the hind tarsi, except its tip, are still rather pale. 

 Tegulse with black cilia. Wings tinged with gray ; more brown- 

 ish-gray along the anterior border ; costa with a hardly perceptible 

 thickening at the tip of the first longitudinal vein ; fourth longi- 

 tudinal vein not broken. 



Hob. Washington, D. C. (Osten-Sacken.) 



36. I>. praeustus LOEW. . Aeneo-viridis, nitens, facie ex cinereo 

 ochracea, antennis nigris, ciliis oculorum inferioribus albidis, tegularum 

 ciliis nigris, pedibus testaceis, litura femorum anteriorum, femoruin 

 posticorum apiee, tarsis anterioribus inde ab articuli primi apice, tarsia 

 posticis totis cum tibiarum posticafum apice nigris, alarum ex cinereo 

 hyalinarum apice nigro. 



Bronze-green, shining; face grayish ochre-yellovr ; antennse black; cilia 

 of the inferior orbit whitish ; cilia of the tegulse black ; feet luteous- 

 yellowish ; a stripe on the fore-femora, the tip of the hind femora, the 

 four anterior tarsi from the tip of the first joint, and the hind tarsi 

 altogether, as well as the tip of the hind tibiae, black ; the tip of the 

 grayish-hyaline wings black. Long. corp. 0.21. Long. al. 0.21. 



SYN. Dolichopus prxustus LOEW, Berl. Ent. Zeitschr. 'VI, 212, 62. 



Bronze-green, shining. Face grayish-yellow. Antennae alto- 

 gether black ; their third joint short. Front metallic green, some- 

 what dusted and therefore but little shining t Occipital bristles 

 very long. Cilia of the inferior orbit whitish. Last segments of 

 the abdomen generally somewhat colored with coppery. Lamellae 

 of the hypopygium of medium size only, broad, with very rounded 

 upper border, white, bordered with black, bristly along the upper 

 and apical edge ; the latter somewhat jagged. Coxae blackish, 

 their tip brownish-yellow ; the fore coxae with a grayish-white dust 

 and hairy with black. Feet brownish-yellow ; the fore femora on 

 the under side with a brownish-black longitudinal stripe ; the hihd 

 femora before the tip with a black bristle and tinged with black 

 on the upper side of the tip ; the delicate hairs on their under ide 

 are somewhat longer than in many other species, although they 

 cannot be called cilia. The hind tibiae are blackened towards 

 the tip, and have, towards the end of the upper side, a rather dis- 

 tinct dimple or impression ; their hind side has no glabrous stripe. 

 Tarsi plain, the four anterior ones from the tip of the first joint, 

 the two hind ones altogether black. Cilia of the tegulas black. 

 Wings grayish hyaline, the extreme tip of the wing black ; the 



