THE SYRPHIDAE OF OHIO 67 



In 1889 these larvae were reported seriouslj' damaging corn at Cadet, 



Missouri in August. Here they were feeding between the base of the 



leaf and the stem in large numbers causing a wilting and browning of all 



the lower leaves, an effect "Exactly the same as that produced by the 



Chinch bug." 



"j5Vo-— The egg, according to Mr. Ashmead, is pure white, elongate-oval, with 

 longitudinal and intersecting cross-lines or grooves, not apparent to the naked eye. 

 It measures nearly i mm. in length. 



'■'■Laiiia — Average length about 7 mm. Slender, subcylindrical, tapering anteri- 

 orly, its posterior end slightly flattened. The whole body is divided by apparently 

 36 annulae, and its surface is closely granulated. Mandibles black. The last 

 segment bears the two short, stout, polished, dark yellow spiracular tubes, each with 

 three spiracles at the tip. Color pale yellowish, or more or less of the color of the 

 pollen, with 2 medio-dorsal, slender, somewhat wavy purple lines, which start con- 

 jointly on the first segment, diverging but slightly posteriorly, and terminating on 

 the anterior portion of the penultimate segment, which latter is marked in addition 

 with somewhat reddish and squarish spots, arranged in transverse square. 



''Pupanum — I^ength 5 mm., to 7 mm. Clavate, subcylindrical, slightly curved, 

 it? anterior end thickest and rounded. The posterior end has a median carina and 

 rather sharp lateral edges and more or less flattened ventral side. The last segment 

 bears the two spiracular tubes with black spiracles, the upper one of which is smallest 

 and round, whilst the tvvo other large ones which are placed close above each other 

 are transversel}' oval. Color greenish or brownish-j'ellow, marked often with a more 

 or less distinct dusky median, an interrupted subdorsal, and a lateral line. The 

 median line isgenerall}- present only along the posterior carina." 



Sphaerophoria — ^. cylindrica aphidophagous. See p. 59. 



"Some species are known to be aphidophagous and S. flavicauda is 

 in some way associated with the ordinary garden Asparagus and may l)e 

 found rather commonly upon the flowering plants." Verrall, British 

 Flies p. 427. 



Riley, Dept. Agr. 1889, p. 351 reports the larvae of 5". cylindrica as 

 feeding on Siphonophora avcnae. 



Sphegina and Neoascia — Metamorphoses apparently not known. 



Rhingia — "The metamorphoses are supposed to occur in cow-dung, 

 and Schiner suggests that in flight and color the species mimic the red- 

 dish species of Aphodius." Verrall, British Flies, p. 478. 



Brachyopa — -"Our one British species {bico/o)-) has been bred by 

 Leon Dufour from the flowing, ulcerous sap of an elm, and as it has been 

 captured in England where the sap was exuding from a tree-trunk, there 

 can hardly be any doubt about its habits." Verrall, British Flies, ji. 475. 



Copestylum— Williston, F^nt. News, II, 162, notes the rearing of 

 Copestylmn margijiatiDn from larvae feeding in the tissues of the common 



