38 Syrphidae. 



5. Gubital vein without any loop or veinlet down in 



the first posterior cell V. Chrysotoxinae. 4^ li 



— Gubital vein with a veinlet down in the first posterior / 

 cell, sometimes issuing from a more or less angul- 



ated loop 6. 



6. Antennæ with a dorsal arista; scutellum with two 



small spines or processes VI. Microdontinae. 7 i' 



— Antennæ with a terminal style; scutellum unarmed VII. Ceriinae. wj- 



I. Syrphinae. 



Antennæ short or of moderate length, not porrected or not 

 distinctly so; arista bare or short-pubescent, Epistorna with or with- 

 out central knob, sometimes with a central knob in the male. none 

 in the female; otherwise it ranges from straight and flat to consider- 

 ably hollowed below the antennæ with the knob much produced and 

 below the knob either only retreating, or again produced at the upper 

 mouth edge; sometimes the epistorna is conicaliy protruding; it is 

 densely or more or less moderately haired, or bare, and it is black 

 or yellow with or without middle stripe. Eyes usually touching in 

 the male. Subcostal cell open; medial cross-vein before the middle of 

 the discai cell; cubital vein straight or slightly curved, in a few cases 

 somewhat looped; stigmatical cross-vein never present. 



The larvæ of most genera are aphidiphagous and somewhat leech- 

 like; that of Chrysogaster has been found in mud and flood refuse, 

 and has a short tail; Chilosia lives as larva internally in piants or in 

 fungi; Xanthogramma and Doros have been found on the earth under 

 moss and stones, Neoascia in flood refuse, it has a short tail, and 

 Brachyopa in sap of ulcerated trees. 



This subfamily contains by far the largest number of genera and 

 species, and it is not quite homogenous; it is especially the first 

 genera, Paragus and Pipiza and allied genera which stand somewhat 

 separate, and again such genera as Baccha, Neoascia and Phingia, 

 while the genera of the other large group seem to be naturally allied. 



Table of Genera. 



1. Epistorna not hollowed below the antennæ, somewhat 

 flat, straight or retreating, about parallel with the eye- 

 margins and without central knob or produced mouth edge; 

 it is black or æneous; epistorna and eyes hairy; dark 

 species with no pale markings on head and thorax 2. 



— Epistoma with a central knob, or with the Iower part 

 produced, or both with central knob and produced mouth 

 edge 6. 



