DIPTERA. 293 



2. Hind metatarsi black quadripunctatus, sp. n. 



Hind metatarsi, except the tip, light yellow 3. 



3. Mesonotum dark red pulcher, sp. n. 



Mesonotum black, with light yellow markings 4. 



4. Thorax, except the yellow margins of the mesonotum, wholly black . similis, sp. n. 

 Pleurae with yellow and red markings rogersi, O. Sack. 



Systropus rogersi (?) (p. 158). 



To the locality given, add : — Mexico, Amula in Guerrero (H. H. Smith). 



A single female specimen from Guerrero perhaps belongs to this species. The head 

 and thorax agree pretty well in colour with the description, save that the whole 

 posterior underpart of the latter, from the base of the abdomen to the hind coxae, is 

 red. The abdomen is brown above, not black, and reddish-yellow on the underside. 

 The hind femora are yellow, with the upperside on the basal half brown. 



7. Systropus dolorosus, sp. n. 



c? $ • Frontal triangle and sides of the face silvery. Antennae black ; second and third joints taken 

 together as long as the first, the third nearly twice the length of the second. Thorax black ; a transverse 

 spot on the humeri, one in front of the root of the wings, one on the post-alar callus, and one above the 

 front coxae, light yellow. Abdomen reddish-yellow, the base and distal segments black. Legs black or 

 deep brown, the knees narrowly reddish. Wings brownish. Length 14-16 millim. 



Hab. Mexico, Jalisco {Schumann), Temax in Yucatan (Gaumer). 



Four specimens. The two from Yucatan have the yellow spots of the dorsum of the 

 thorax smaller or obsolete, and the dorsum of the abdomen black or brown throughout ; 

 they are also larger than the others. This species can hardly be the same as 

 S. angulatus, Karsch, as the anterior branch of the third vein is not angulated, and no 

 mention is made of the pleural spot. The presence of the yellow spot on the pleurae 

 will distinguish S. dolorosus from S. infuscatus and S. imbecillus, Karsch. 



8. Systropus quadripunctatus, sp. n. 



9 . Frontal triangle, save the uppermost portion, and the sides of the face, light yellow. Antennae black, the 

 basal portion of the first joint yellowish; first joint only a little longer than the second and third joints 

 together, the third about one and two-thirds the length of the second. Thorax black ; mesonotum with 

 a hoary geminate stripe in the middle ; the sides from in front of the root of the wings, extending 

 inwardly, anteriorly, and downwards to the front coxae, and a small spot on the post-alar callus, light 

 yellow ; the whole posterior inferior part, from the base of the abdomen to the hind coxae, and including 

 the hypopleurae, also light yellow, and with four small black spots arranged in pairs. Abdomen red, the 

 first three or four segments black above, the distal segments brown. The four anterior legs are light 

 yellow ; hind femora brown, yellow below distally ; hind tibiae blackish : hind tarsi black. Wings 

 tinged with brownish. Length 13-15 millim. 



Hal. Mexico, Northern Yucatan (Gaumer). 



