78 STRATIOMYID.E 



suture and Avith the actual front iiart (juite impunetate and consequently bare 

 and polislied, l;ut rather more coarsely punctate behind the suture; pubescence 

 very minute, recumbent, and scarcely visible in front of the suture because it 

 is blackish there, but rather more obvious after the suture because it is 

 greyish yellow there ; pleurae with scarcely any pubescence, and with nearly 

 all the mesoiileune impunctate and very brilliantly polished. Scutellum 

 shining black, slightly dulled by the dense coarse punctuation and by minute 

 Ijlackish pubescence. 



Abdomen shining black, rather densely but not very coarsely jjunctate, 

 and each punctuation bearing a tiny decumbent blackish bristle, though 

 towards the tip these tiny bristles become scarcer and more greyish. Belly 

 brightly shining black, and bearing fine rather sparse, depressed, almost 

 whitish, short pubescence. Genitalia (when exserted) about as wide as a 

 third of the hindmargin of the fifth abdominal segment, blackish with slight 

 orange colorings. 



Legs yellow, slightly obscure on the femora ; tarsi pale yellow even to the 

 last joint, though the tiny claws are black ; coxje blackish ; trochanters 

 yellow ; hind femora with a rather indefinite blackish ring just before the 

 tip. Pubescence very slight, Imt there are some tiny pale hairs behind the 

 anterior, and in front of the hind, femora. 



"Wings almost hyaline and minutely pubescent all t)ver, but the stigma is 

 ])ale yellowish and the veins pale brownish yellow on the anterior part up to 

 the end of the cubital vein and farther still along the costa and on the stem 

 and lower fork of the postical vein, while the other veins are very faint ; fork 

 of the cul)ital vein distinct and almost perpendicular, Avell beyond the middle 

 of the submargiiial cell. Squamaj Idackish, with brownish orange margins 

 and fringes. Halteres with large blackish knobs, but with brownish orange 

 stems. 



9 . Very much like the male. Frons shining black, at the top about one-third 

 the widtli of the head but gradually diminishing in width down to the trans- 

 verse channel a little above the antennae where it is about one-fifth the width 

 of the head ; after this the eyes very gradually diverge down to the mouth ; 

 l)ubescence on the frons so short ancl sparse as to be almost imperceptible 

 even though pale, unless viewed absolutely sideways, Init more visible on the 

 very short face ; lower part of the head so much flattened that the jowls 

 can hardly be traced when viewed sideways, but when seen from beneath they 

 are fairly wide and are shining black ; back of the head olwiously puffed out, 

 especially on the lower part, but not so much as in F. atra, and bearing 

 very inconspicuous tiny pale pubescence. Eyes more circular than in the 

 male. Antennae all dull orange, with the third joint larger than in the male 

 and sometimes slightly brownish. 



Thorax and scutellum rather more densely punctate than in the male, 

 except on the impunctate front part of the thorax, and both bearing very 

 short decumbent light grey pubescence except on the bare polished parts. 



Abdomen with more uniform tiny decumbent greyish bristles ; ovipositor 

 (when visible) long and yellowish. 



Legs more whitish yellow, and the blackish marking just before the tip of 

 the hind femora sometimes reduced to a blotch on the front part, ancl 

 sometimes with even that only brownish. 



Wings almost as in the male. Squamse paler, being brownish or orange. 

 Halteres with the knob more brownish. 



Length about 3-35 mm. 



This species is very easily distinguished from the other four European 

 species by its yellow femora, while its hyaline wings with the forked 

 cubital vein distinguish it from all except P. orlitalis. 



P. Leachii is by no means a common species in England, though I 

 expect it will be found to be much more widely distributed than is known 

 at present, and perhaps when its breeding habits are known it may be 

 found more commonly. Ferris (Ann. Soc. Ent. France, 1870, p. 212) 

 stated that he bred it from larv?e found in a Boldns in a hollow oak, or as 



