7. MACHIMUS 669 



species with far more numerous white bristles on the thorax and legs, 

 short inconspicuous fine ciliation beneath the front tibite, and only two 

 long white bristles on the scutelluni. M. rudicus has the tibite 

 rufescent at just the base, and has also far more numerous white bristles 

 on the thorax, scutellum, and legs, and also more abundant long pale 

 pubescence on the back part of the thorax, while in the female the end 

 lamellce of the ovipositor stand out clear and free from the apex of the 

 upper piece of the ovipositor (fig. 359). 



E. rufibarhis appears to be rare in Britain, though the old collections 

 of the British Museum and the late J. C. Dale contain several specimens. 

 I caught a female at Weybridge in Surrey on June 29, 1872, and Colonel 

 Yorbury and Mr C. J. Wainwright have since taken about four specimens 

 in the New Forest ; Colonel Yerbury and Mr J. E. Collin caught a male 

 and two females at Tangham Forest in Suffolk at the end of August, 1907; 

 one of Mr Dale's specimens was labelled "Coombe Wood, August 18, 

 " 1817," and Mr J. E. Mason has recorded it from Mumby Chapel in 

 Lincolnshire. My dates extend from June 24 to August 29. It is 

 recorded from Middle and North Europe. 



Synonymy. — This species stood under the name of A.forcijiatus in the collections 

 of the British Museum and Mr J. C. Dale, and also under the name of A. fimhriatus 

 in the British Museum. 



7. MACHIMUS. 

 Machimus Loew, Linn. Ent., iv., 1 (1849). 



Rather large flies of blackish or brownish grey colour. 

 Males with a process from the eighth ventral segment. 



Face rather broad (except in M. atricajyillus and its close allies); face-beard long 

 and rather strong, but leaving at least the top quarter and the side thirds of the 

 face bare ; postocular festoon present, though the bristles may be few in number 

 and only shghtly bent forwards at their tips ; frons with small bristles or hairs at 

 the sides ; collar with some stout bristles on the upper part. Antennae normal ; 

 basal joint with long bristles beneath, but the second joint with only short bristles ; 

 third joint elongate narrow elliptical, and terminated by a long thin jointed style. 



Thorax with very short bristles rather than pubescence all over the disc, includ- 

 ing all over the stripes. Bristles ; two strong prsesutural (with often a smaller third 

 one), two or three supra-alar, two or more postalar, about four (3-6) well defined 

 dorso-central postsutural and sometimes about three somewhat indistinct prae- 

 sutural extending not more than half-way between the suture and the front of the 

 thorax. Pleuras with no special pubescence, but the metapleural fan composed of 

 long and distinct bristles or even fine hairs and the hypopleural fan also distinct. 

 Scutellum pubescent, and bearing (2-8) strong upturned marginal bristles or bristly 

 hairs. 



Abdomen with moderately strong but conspicuously contrasted hindmarginal 

 bristles (sometimes reduced to one) near (but not extending far away from) the sides, 

 which however become very few or die out after the fifth segment ; eighth ventral 

 segment produced at the middle of the hindmargin into a more or less trowel- 

 like prolongation (which is pronged in M. atricapillus) on which the pubescence 

 usually becomes long and bristly, and this valuable generic character (though not 

 always very conspicuously developed) is very obvious in our two British species. 

 Genitalia of the male of moderate size, neither compressed nor swollen ; claspers 

 usually simple • ovipositor pointed triangular, sometimes rather elongate but never 

 linear, distinctly compressed laterally, and with two rather long free almost style- 

 like lamellie at the tip (fig. ,359) but with no circlet of short spines. 



Legs rather stout (though not much so in M. atrica2nllu&) ; femora more or less 



