No. 2080. NEW SPECIES OF CRANE-FLIES— ALEXANDER. 443 



Rostrum bluish black at the tip, light brown basally, palpi black. 

 Antennae brownish black, the flagellar segments rounded oval. Head 

 reddish chestnut, darker on the middle of the vertex. 



Thoracic dorsum dark chestnut with three black stripes, the 

 median one longest, the lateral stripes very indistinct, clearer behind ; 

 the region near the transverse suture including the posterior part of 

 the praescutum and the anterior part of the scutum light yellow; 

 scutum trivittate with black; scutellum and postnotum chocolate 

 brown, more yellowish on the sides. Pleurae reddish yellow. Hal- 

 teres brown. Legs with the coxae and trochanters reddish, femora 

 dark brown, pale yellowish at the base, tibiae and tarsi black. Wings 

 whitish hyaline with small brown marks at the origin of Rs, on cross- 

 vein r, along the cord, on the basal deflection of Ou t and along the 

 outer end of cell 1st M 2 . Venation as in figure 3; basal deflection 

 of Cu ± far before the fork of M about underneath the middle of Rs. 



Abdomen long, slender, black, the caudal portions of the segments 

 chestnut-yellow, seventh segment mostly chestnut, the hypopygium 

 black. 



Habitat. — Panama. 



Holotype. — Male, Porto Bello, Panama, March 4, 1911, Aug. 

 Busck, coll. 



Paratypes. — Five males, topotypic, same date and collector. 



Type-specimen. — Cat. No. 18498, U.S.N.M. 



Genus ORIMARGA Osten Sacken. 

 Orimarga Osten Sacken, Mon. Dipt. N. Amer., vol. 4, 1869, p. ]20. 



ORIMARGA NIVEITARSIS, new species. 



Black with two silvery lateral stripes on the thorax, tips of the tarsi 

 white, wings unspotted. 



Male. — Length, about 5.8-6 mm.; wing, 4.6 mm. 



Female. — Length, about 6.8-7 mm.; wing, 4.4 mm. 



Rostrum, palpi, and antennae black. Front narrowly silvery 

 between the eyes, remainder of head grayish. 



Thoracic dorsum black, shiny; the lateral margin of the praescutum 

 up to the wing-root narrowly silvery. Pleurae black with a con- 

 spicuous silvery mark, narrowest in front, broader behind. Halteres 

 light brown, knob darker. Legs with the coxae and trochanters dull 

 yellow, femora dark brown lighter on the basal half, tibiae dark brown, 

 tarsi, segment 1 with the basal two-thirds dark brown, remainder 

 of the tarsi white except the terminal segment and claw which are 

 darker. Wings hyaline, veins dark brown, distinct. Venation as 

 in figure 5. 



Abdomen dark brownish black. 



Habitat. — Panama. 



