180 PROF. M. iJEZZI. 



of the back is greyish., like the short hairs of the pleurae ; the very long hairs of the 

 lower part of the stemopleura and breast are whitish. All the macrochaetae are 

 of a deep black colour ; middle scapulars well developed, and about as strong as 

 the lateral ones ; there is no trace, as it seems, of the anterior supra-alar bristles ; 

 pteropleurals short, but strong ; scutellum with the apical pair alone. Halteres 

 whitish. Abdomen entirely black, punctate like the thorax, but distinctly more 

 shining ; it is of a characteristic shape, being narrowed at base, and gradually dilated 

 to the end, very convex at the middle, with almost parallel sides ; the segments 

 are distinctly separate, even along the middle line, on which there is no distinct 

 keel ; the last segment is glistening, and shows distinct traces of two oval, transverse 

 spots of a reddish brown colour on the hind half. The short pubescence is whitish, 

 but rather long on the sides of the first two segments ; the lateral cilia of the 3rd 

 segment are darker and more numerous, but not very long. Venter entirely black, 

 greyish dusted ; male genitalia very small, black. Legs rather short and stout, 

 the front femora being distinctly incrassate ; they have black coxae and black femora, 

 but the latter are narrowly reddish at the tips, and those of the last pair are pale 

 yellowish on the basal two-thirds ; tibiae and tarsi whitish yellow, but all the tibiae, 

 and chiefly those of the front pair, are darkened towards the base ; pubescence 

 whitish, longer than usual ; apical spur of middle tibiae black ; claws whitish like 

 the pulvilli, but with black tips. Wings (fig. 2) proportionally short, with dark 

 brown or even black veins, which show a characteristic disposition. The costal, 

 marginal and submarginal cells are very narrow ; the second longitudinal vein is 

 short, the fifth segment of the costa being thus much longer than the preceding one ; 

 third vein straight and parallel with the last section of the fourth ; small cross-vein 

 long and oblique, its lower end placed on the last fourth of the discoidal cell, and 

 thus the cross- vein itself is longer than its distance from the upper end of the posterior 

 cross-vein ; lower prolongation of the anal cell very long and very narrow, being 

 considerably longer than the terminal part of the anal vein ; this last vein is less 

 divergent from the fifth, and thus the axillary lobe is longer than usual. The wings 

 are greyish hyaline, iridescent, and have a very characteristic pattern, consisting of 

 a broad, fuscous patch of triangular shape, the base of which is placed along the fore 

 border, including the stigma, the whole of the marginal, and the central part of the 

 submarginal cell, and the vertex is on the outer lower corner of the discoidal cell, 

 ending obtusely in the 3rd posterior cell. The terminal part of the submarginal 

 cell is yellowish. Besides there is a greyish spot above the 6th longitudinal vein, 

 just beyond the end of the prolongation of the anal cell. The two cross- veins are 

 both included in the fuscous central patch, but the posterior one is nearer the hind 

 border of the patch. The first basal cell is quite hyaline at base, even above the 

 second basal cell. 



Type (£, a single specimen in the British Museum from S. Nigeria, Oshogbo, 

 9.xii.l910 (Dr. T. F. G. Mayer). 



3. Dacus macer, sp. nov. (fig. 3). 



Falling into section 21 d of my additional Key of 1917 (p. 64), and nearly allied 

 to D. mochii, from which it is distinguished by the quite black abdomen, by the entirely 

 infuscated submarginal cell and by the not infuscated base of the small CTOss-vein. 



