^11 I Atiyust, 



Stating that the scutellum was cither ferruginous or black ; but the presence of other 

 points besides tliis sliow that he mixed two distinct species together ; I shall, there- 

 fore, follow Macquart and Schiner, naming the one with the black scutellum P. 

 casifrons, and the other P. assimilis. 



This species is usually more robust than P. cfssifrons, the forehead is very promi- 

 nent, the frontal stripe rufescent, the frontalia are wider than in ccBsifrons, the arista 

 is thickened nearly to the middle, and has the extremity a little pubescent; the apical 

 cross veins are more oblique and less curved than in ccesifrons, the anal segments of 

 the male are less incurved, the scutellum is almost entirely rufous ; all the other 

 characters are similar to those of the former species. Eare. 



P. UNICOLOE, Flu. 



Shining black, almost immaculate ; frontal stripe dull brown, rather wider than 

 [212] sides of frontalia, which are blue-black and glabrous; antennse black, with third 

 g., ^.-. joint robust, and five or six times longer than second; arista thickened to the 

 middle ; facial setae extending only half way up the facialis ; palpi black, large, and 

 clavate at the ends ; thorax black, with whitish-grey shoulders, four indistinct stripes, 

 and three post-sutural outer dorso-centi-al setae ; abdomen black, with slight cinereous 

 reflections, and setae both on the disc and margins of the segments ; wings with 

 fourth vein bent in a curve, and apical cross vein straight ; legs black, hind tibiae 

 ciliated on outer side with short but even bristles. Eare ; I have only seen one 

 specimen, which was sent to me from Norfolk by Mr. Bridgman. 



P. CILIPEDA, End. 



pavida, Mgn. ?. 



pumicafa, Zett. et Mcq. ?, iion Mgn. 



Blue-black, with hoary pubescence ; eyes long ; chin short ; frontal stripe rufous 

 or black, about equal in width to sides of frontalia, which are grey with bluish 

 reflections ; cheeks bare, pale grey with dark reflections ; facial setae large, and rather 

 far apart, extending fully two-thirds of the way up the face ; antennae with the 

 third joint four or five times as long as the second ; arista thickened to a little 

 beyond the centre, and having a fine capillary extremity ; palpi black ; thorax hoary, 

 with four very fine black stripes, and having four post-sutural outer dorso-central 

 bristles ; scutellum with black base and red margin ; abdomen oval, blue-black, with 

 hoary bands round the front parts of the segments, sides of the second segment red 

 in the male ; both discal and marginal setae ; wings with apical cross vein a little 

 curved, and outer cross vein sinuous ; legs black, posterior tibiae piceous or testaceous, 

 and hind tibiae ciliated along their outer surfaces with an even row of bristles, 

 together with one long seta near the middle. Generally distributed. 



P. pumicata, Mgn., is recorded as British, but I have not seen an example ; all 

 the specimens so named that I have examined have been similar to those of cilipeda, 

 having the hind tibiae more or less rufescent, and ciliated with a somewhat even row 

 of bristles ; I am, therefore, inclined to believe that these two (so-called) species are 

 only varieties of one. P.frontosa, Mgn., has also been recorded as British, but I 

 have not been able to see a specimen. 



