63 [August, 



base in S. notata ; the 4th and 5th longitudinal wing veins are parallel, or slightly 

 divergent at their extremities, in S. maculosa, while the 5th vein converges a little 

 towards the 4th at its extremity in S. notata. The former is the more common 

 species. 



S. 4-MACULATA, Fall. 



This may be distinguished from all of the three following species, to each of 

 which it bears considerable general resemblance, hy the following points of structure : 

 it has the arista shorter haired ; it has only three dorsal thoracic bristles behind the 

 transverse suture in the row between the middle and lateral black stripes instead of 

 four ; and the posterior tibiae are furnished witli a number of long hairs on their 

 inner sides, which are absent in the others. This species is not very common. 



S. DUPLICATA, Meig. 



Several different but very closely allied species have been confounded together 

 under this name. Meigen says, " this species differs manifoldly in colour, size and 

 design ;" which remark evidently shows that he included more than one species 

 under the same designation. I find three vei-y distinct though closely allied species, 

 which may be named dupUcata, duplaris, and communis ; the last will come under 

 the second section, as the legs are partly pale. 



I shall briefly describe the first species, and then point out how the two others 

 differ from it. 



S. duplicata : colour grey ; eyes of male sub-contiguous ; forehead and face 

 very slightly prominent ; antenna; rather short ; arista long haired ; thorax with 

 four longitudinal black stripes (the outer of which are interrupted at the suture) 

 placed rather close together, and sometimes rather indistinct ; four dorsal bristles 

 behind the suture ; scutellum marked with a fugitive brown spot at the base ; abdo- 

 men narrow and conical, whitish-grey, with four black spots, two on the second and 

 two on the third segment, which vary in size and shape, being sometimes round and 

 sometimes square 'ov triangular ; in some specimens, an indistinct longitudinal 

 dorsal stripe is also present between the spots ; wings clear with black veins, which 

 are sometimes slightly clouded ; external transverse vein mostly straight, but more 

 or less oblique ; internal transverse vein placed over the discoidal cell at about two- 

 fiftlis from its end ; costal spine distinct ; calyptra yellowish-white ; halteres yellow ; 

 legs black ; posterior tibiae thickly clothed with short hairs on both sides, and having 

 several strong bristles of uneven lengths on their outer surfaces. The female has 

 the eyes widely separated by a grey-coloured frontal space, having a bifurcated black 

 mark in the fore part. The external transverse veins are usually less oblique than 

 in the male, and the posterior tibise have a slight rufous tinge ; it other respects it 

 closely resembles the male. Length of <? and ? , 2 to 2^ lines. 



The late Professor Rondani to whom I sent some specimens for his inspection, 

 said that in his opinion it was the S. duplicata of Zettcrstedt, but not that of 

 Meigen. This species is not uncommon, I have found it upon the ground on path- 

 ways m. fields. 



S. DUPLAKIS, Zett. 



This species differs from S. duplicata by being rather larger and stouter in 

 shape ; by having the abdomen more oval ; by the absence of the brown mark at the 

 base of the scutellum ; by the lines on the thorax being narrower and more distinct ; 



