26 PEOCEEDINGS OF THE NATIONAL MUSEUM vol. 08 



latter yellow. Abdomen black. Legs black, tibiae and tarsi yellow^ 

 hind tibiae more or less fuscous. Wings smoky. Halteres dark. 



A robust species. Thorax fully as wide as long, scutellum twice as 

 wide as its length at center. Legs stout, fore femur with strong 

 posteroventral bristles; fore tibia with short posteroventral setulae. 



Length, 1.75 mm. 



Type. — Higuito, San Mateo, Costa Rica (P. Schild). Cat. No. 

 28459, U. S. N. M. 



In this genus the wing venation shows an approach to that of 

 Steganops^ls latipennis Coquillett. 



Family AGROMYZIDAE 



This family is distinguished from its allies by the presence of 

 vibrissae, the postvertical bristles being divergent, the basal cells of 

 wing both present, and the auxiliary vein very close to first vein or 

 fused with it. 



In this paper I describe one new genus and three new species. 



SCHILDOMYIA, new genus 



Generic characters. — Of the same habitus as Odinia Robineau- 

 Desvoidy, but differing as follows : The divergent postvertical bristles 

 much closer together, situated on edge of vertex, and more widely 

 separated from posterior ocelli than length of ocellar triangle, the 

 latter elevated; frontal lunule sparsely haired; orbital bristles in 

 three pairs as in Odinia, the anterior pair incurved; an upwardly and 

 forwardly directed bristle well above margin of cheek, not on margin 

 as in Odinia. Only four pairs of dorsocentral bristles present, one 

 pair presutural; posterior intra-alar present; scutellum haired on 

 disk. Fourth wing vein not deflected apically, the first posterior cell 

 therefore not widened, but slightly narrowed, apically, the costa 

 not obviously discontinued at apex of third vein, but continued rather 

 noticeably to apex of fourth. Hind femora not abnormally thick- 

 ened, unarmed on anteroventral surface near apex. 



Genotype. — Schildomyia vittithorax, new species. 



KEY TO SPECIES 



1. Arista long haired, plumose; prescutellar acrostichals absent; proplenral 



bristle not duplicated; scutellum with a large dark brown spot on each 

 sifle which cover entire lateral margins and almost meet in center of 

 disk, leaving only the base and apex gray in center; orbits with dark 



spots vittithorax, new species. 



Arista pubescent ; prescutellar acrostichals present ; propleural bristle 

 duplicated; scutellum with the lateral margins pale 2 



2. No dark spots at bases of the frontal orbital bristles ; antennae yellow. 



brevihirta, new species. 

 A dark spot at base of each orbital bristle; antennae largely black. 



punctifrons, new species. 



