1897.1 



123 



closely imbricate and appressed ; tlien lying gradually looser tlicy presently became 

 distichous and acuminate : on the mediastinal nervure the scales are distichous, 

 more slender and longer; and along the opposite part of the costa interior to the 

 fringe are some rather shorter slender scales lying obliquely. Anal nervure as it 

 were beautifully plumose, being beset near the base with extremely long, compressed, 

 capillary scales succeeded gradually by very long, silky hairs, arranged (both scales 

 and hairs) in two divergent crowded ranks : the anterior rank slanting forwards ; 

 the posterior, longer and denser, pendant and in length subequal to the neighbouring 

 portion of the marginal fringe. Axillar nervure also with distichous scales and hair 

 much shorter than those last mentioned or the fringe ; the scales acicular, and the 

 hair very fine and silky. 



Fringes or beard of the hinder pairs of legs dense long and shaggy on the 

 tibia, and dwindling on the 2nd tarsal joint to nothing : on tiie sole, the gloss at 

 the tip can be made to extend to the 4th joint. In the fore leg, the coxa in front 

 and the femur beneath are densely bearded with long acicular or linear scales. 



$ . The dark blotch upon the radial branches does not extend inwards to the 

 bifurcation. Axillar nervure of normal strength, slightly sinuate, clad in its basal 

 half with bristling hair. Fringe of the alula in no way remarkable. Beneath at the 

 wing-roots are some acuminate scales, restricted almost entirely to parts interior to 

 the fold of deflection, and succeeded almost immediately beyond this by flattened 

 hairs of ordinary character and arrangement. 



The contrast between the white gloss of the last four tarsal joints in tlie $ and 

 the sombre tint of the three penultimate joints in the ^ , caused all previous authors 

 to reckon the sexes distinct species : but Zetterstedt possibly overlooked it in 

 specimens lie caught in cop. The accompanying differences in the contour and 

 under-clothing of their wings are also very remarkable. 



After discovering the confusion of species of this Section, 

 mentioned ante, 2nd ser., vol. vi, 209 (Sept., 1895), much difBculty was 

 experienced in adjudicating finally upon their respective synonymy, 

 and in the meanwhile one working-hypothesis after another had to be 

 reluctantly abandoned. For a short time the possibility of reviving 

 Meigen's name calceata for one of them was entertained : hence the 

 superseded nomenclature issued in Mr. Richardson's note, supra, p. 65 

 (March, 1896). But a few days later, opportunity was taken to 

 examine Mr. Dale's collection in order to see whether any specimens 

 were still extant likely to be those referred to by Haliday under this 

 name in Walker's work, his reference governing its application. Both 

 of the species occur at Glanvilles Wootton, and both were intermixed 

 under one label in the cabinet ; but the only specimens among them 

 mounted on old fashioned pins of ancient date were a male and a 

 female of the present species. At the same time on comparison of 

 Curtis's figure of the wing with actual specimens, it was recognised as 

 a representation of the wing of a male of the next species : hence 



L 2 



