THE BIBIONID^. 157 



S. Jlavicollis, Mg. — S. oc/iracea, Mg. 



Tawny ; head black ; antennai at base yellowish ; palpi dark 

 brown ; thorax tawny ; scutellum tawny or brownish ; sides of the 

 breast light. Abdomen black above, except the hind borders of the 

 segments, anal segment pale brown. Legs light brown; tarsi darker. 

 Halteres yellowish. Wings: costal short; first, second, and third 

 veins tawny ; the fork of the fourth very long ; petiole short ; trans- 

 verse veinlet small : sixth scarcely undulating. Lower veins all pale. 

 Length i to i\ lin. This is an autumnal species, and frequents the 

 flowers of ivy, and ali^o found withZ/Vfr?.* 



.S". Al/'ifarsis, Zett. 



This is a black species, with long body and milky wings, with 

 white tani. Length i] to ih lin. Common. 



.S". transversal is, Lw. 



Black. The veining of the wings easily distinguishes this fly. 

 The second vein short and curved abruptly upwards to the costa ; 

 the third undulated, transverse veinlet between them thick ; the 

 fourth forked, petiole short and fork long, arising nearer the base of 

 the wing than the transverse veinlet ; the upper J>rotig of the fork 

 U7iited to the third by a long transverse veifilet, the prong angu- 

 lated at the origin of the veinlet ; fifth nearly straight ; sixth bent 

 abruptly to posterior border and undulated. Length | to i lin. 

 Verrall records it as occurring freely on a tree near Thetford, lune 

 17, 18S0. 



6". luevicornis, Mg. =-- S. septe/nnodia, Schrk. 



Dark black ; antennae very short and deep black ; legs and hal- 

 teres also deep black. Wings milky ; second and third longitudinals 

 short, running close together and curved up abruptly ; costal very 

 short ; fourth forked near its apex, petiole of fork very long ; eighth 

 nearly straight ; sixth with an abrupt undulation. This fly is distin- 

 guished at once by the shortness of the second and third longi- 

 tudinals and by the curious short fork of the fourth. Length h to 

 f lin. A fairly common insect. 



.V. ha/terata, ^g. = [^- '''^''P'^"^^'^ ^- ^o^^"-' 

 \S. niinuta, Zett. 



Black ; antenns thick, long ; proboscis and palpi black ; halteres 

 white. Wings whitish ; second longitudinal short, about one-fourth 

 length of wing ; third running near it, and ending at about half the 



* Walker mentions a variety with disc of thorax lilack. 



