SYSTEOPUS. 159 



pale reddish-yellow, including the coxae ; hind femora more reddish ; hind tibiae and 

 tarsi brown. Wings tinged with greyish ; stigma brown. A single male. 



3. Systropus lugubris, sp. n., ? . 



Black, including the legs ; only the distal third of the hind tibiae yellowish-white. 

 Length about 25 millim. 



Hab. Mexico (Sumichrast, in coll. Bellardi). 



Sides of the face yellowish ; facial orbits silvery ; antennae black, the third joint a little 

 more than twice the length of the second. Thorax black ; the humeri with small pale 

 yellow spots ; pleurae hoary, beset with white hairs. Abdomen black ; venter paler on 

 the first four segments ; with fringes of silvery hair on the incisures of segments 2-4 . 

 Legs black ; front femora with a trace of reddish near the base on the posterior side ; 

 four anterior tibiae silvery on the posterior side ; distal third of the hind tibiae yellowish- 

 white, the extreme tip, however, black. Halteres black. Wings tinged with brownish- 

 grey, darker near the costa. A single female. 



4. Systropus rufiventris, sp. n., s . 



Four anterior legs yellow ; hind legs black, with the bases of the femora and tibiae, and the first joint of the tarsi, 

 except its tip, yellow ; humeri and sides of mesonotum yellow ; abdomen black at the base and along the 

 back, reddish on the underside and sometimes towards the tip also. 



Length 22-25 millim, 



Hab. Mexico (Sumichrast, in coll. Bellardi). 



Sides of the face and the lower part of the frontal triangle yellow ; facial orbits silvery ; 

 antennae black, the third joint but little longer than the preceding one. Thorax black ; 

 sides of the mesonotum from the humerus to the root of the wings yellow : this yellow 

 sends out one branch which connects the humerus with the yellow front coxae, 

 and another shorter branch (separated by a black space from the corresponding 

 branch on the opposite side) forms the anterior margin of the mesonotum. Halteres 

 yellow. Abdomen : the first four segments black above, pale reddish-yellow below ; 

 the following segments more or less reddish-brown above, and reddish below, some- 

 times altogether reddish. Four front legs, including the coxae, yellow; hind legs 

 black; hind femora at the root more or less yellow, especially on the underside; 

 proximal third of the hind tibiae and the first joint of the hind tarsi (except the tip) 

 yellow. Wings tinged with pale brownish. 



5. Systropus sallsei. 



Systropus sallei, Costa, Ammario del Museo Zool. della R. Univ. di Napoli, 1864, p. 151 ; O. Sacken, 

 Cat. of N.-Am. Diptera, 1878, Additions and Corrections, p. 265 (where the diagnosis is 

 reproduced) . 

 Hal. Mexico (Sumichrast). 



