596 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 86 



Genus HETERACANTHIA Macquart 



HETERACANTHIA RUFICORNIS (Macquart) 



Three females, Higiiito, San Mateo, Costa Rica (Pablo Schild). 

 Genus MACROMERACIS Enderlein 



MACROMERACIS LONGICORNIS (Philippi) 



Figure 71, c 



One female, Ancud, Isla Cliiloe, Chile, December 1926 (R. and E. 

 Shannon). This specimen seems to belong to Philippi's Beris l&ngi- 

 comis, and is clearly a Macromeracis^ though differing somewhat in 

 venation from Enderlein's diagnosis of the genus. It is here de- 

 scribed in detail because of the brevity of Philippi's description. 



Female. — Head black, subshiiiing, with inconspicuous yellow hair; 

 the occipital orbits (which are developed only on the upper part and 

 are there very narrow), lower third of the front, and face whitish 

 pollinose. Antennae black (segments beyond the second missing). 

 Palpi and proboscis bright yellow. Thorax yellow; the dorsum, ex- 

 cluding the humeri, however, is brownish and becomes black laterally 

 in front of the suture and posteriorly before the scutellum. Meta- 

 pleura blackish. Scutellum blackish in the center, that color gradually 

 merging into the broad yellow margin. Scutellum with four spines, 

 the lateral pair directed outward, the median pair one and one-half 

 times as long as the scutellum and three times as long as the lateral 

 pair. Legs entirely yellow, the tarsi at most somewhat brownish at 

 the apex. Discal cell large, two and one-half times as long as wide; 

 the cross-vein r-m joins it at its basal fifth, and its apex reaches almost 

 halfway between r-m and the origin of R.j. Four posterior cells ; the 

 fourth borders the discal cell for a gi^eater distance than does the third. 

 Abdomen three times as long as wide and three times as long as the 

 thorax (excluding scutellum) and j'ellow, the first four segments 

 dorsally with posterior subquadrate black spots, which are bluish in 

 certain lights; those of the first segment are confluent with those of 

 the second; a broad transverse band of similar color occupies the fifth 

 and a broad, semicircular area on the basal and medial part of the 

 sixth ; this is confluent with the posterior spots of the fourth segment. 

 Pile yellow, inconspicuous. Length, 7 mm. 



The form of the discal cell readily distinguishes this species from 

 M. elongata Aubertin and M. thoracica (Philippi). 



Genus BERIDOPS Enderlein 



BERIDOPS MACULIPENNIS (Blanchard) 



Male, Bariloche, Rio Negro, Argentina, November 1926 (R. and E. 

 Shannon). 



