296 PROCEEDINGS OF THE NATIONAL MUSEUM vol.88 



of segment 4, segments 4 to 10 usually equal, somewhat variable, 11 

 and 12 slightly shorter than 10, 13 usually equal to 10; scrobe cavity 

 shallow, carinate at ventral margin and ventral half of lateral mar- 

 gins, the latter strongly curved mesad ; interantennal projection with 

 a minute, vague anterior carina; frons minutely reticulated, almost 

 glabrous ventrad of antennal bases, pubescence short, sparse; frontal 

 tentorial pits located ventrad and laterad of antennal bases ; width of 

 malar space one-third height of compound eye; frontogenal suture 

 slightly curved; combined widths of compound eyes equal to inter- 

 ocular width at level of antennal bases; left mandible with two 

 acute teeth, dorsal one larger, right mandible with three teeth ; diam- 

 eter of posterior ocellus from slightly more than one-half to three- 

 fifths width of interocellar space; head, from dorsal aspect, one-half 

 as long as wide. 



Dorsum of thorax with close irregular punctures, pubescence in- 

 conspicuous except at lateral margins of thorax, where it is slightly 

 longer and stouter; anterolateral angles of pronotum mintely cari- 

 nate; anterior dorsal margin acarinate; parapsidal furrows distinct; 

 prepectus not visible; apex of mesoscutellum with a narrow, mesally 

 depressed lamina; metepisternum covered by large, shallow punc- 

 tures, pubescence short and fine; metacoxae with entire surface sha- 

 greened, setose on outer ventral side, sparsely so on dorsal; meta- 

 femora with outer surface minutely reticulated, pubescence short, 

 sparse, ventral margin provided with 16 to 20 small, closely set teeth, 

 basal one slightly larger ; inner tooth sharp. 



Propodeum usually entirely without setae, surface provided with 

 strong carinae, areas between carinae glabrous, spiracular openings 

 oblique, one very slight projection present at each posterolateral angle 

 of propodeum; petiole two and one-quarter times as long as wide, 

 entire surface shagreened and uneven, basal lamina wide, lateral 

 carinae absent; gaster acuminate, slightly longer than metafemur, 

 abdominal tergites 4 to 7 with long, sparse lateral setae; eighth 

 tergite minutely and obscurely reticulated, setae long, sparse; spi- 

 racular openings round; cerci oval, located midway between ante- 

 rior and posterior margins of epipygium ; apex of ovipositor sheaths 

 with a few short ventral setae. 



Male: 2.5-3 mm. Antennal scape (fig. 8, q) enlarged in the mid- 

 dle; flagellum stout, segments usually as wide as long; width of 

 malar space two-fifths height of compound eye; combined widths of 

 compound eyes slightly less than interocular space at level of antennal 

 bases ; petiole four times as long as wide. 



Type locality. — Florida. 



Types. — Holotype, male, 51949, U. S. National Museum. The 

 female was described as SpilochcHcis syrphidis Wolcott, from Puerto 



