146 .. DIPTERA. 



The hind femora, on the outer side, beset with long, soft 

 hairs, without any series of stronger spinules. 

 Face with white, erect hair ; male forceps projecting, 



but of moderate size 8. A. carbonarius, sp. n., cJ ? . 



Face with black, erect hair; male forceps nearly as 



long as half the abdomen 9. A. peodes, sp. n., $ ? . 



l. Aphoebantus cyclops, sp. n., <? $ . (Tab. III. figg. 4, 4 a-c, 6 .) 



Male. General covering of the body greyish-black ; thoracic dorsum, scutellum, and abdomen clothed, besides the 

 longer hairs, with a short, appressed, rather rare fulvous tomentum, not dense enough to conceal the ground- 

 colour ; in the middle of the mesonotum this tomentum forms three, often indistinct, stripes, the lateral of 

 which contain many white hairs, especially on tbeir anterior portion, and thus appear (at least in well- 

 preserved specimens) whitish ; on each side, between the humerus and the post-alar callus, above the root 

 of the wing, is another stripe of short, white, erect hairs ; pleura with a large tuft of white hairs in front 

 of the root of the wing, and another one below more or less coalescent with it ; first segment of the abdomen 

 posteriorly with a dense fringe of short white hairs, forming a distinct cross-band which is slightly interrupted 

 in the middle ; almost imperceptible whitish fringes on the other segments ; the whole abdomen clothed 

 with a fur of long, soft hair, the whitish colour of which becomes visible in a certain light only, especially on 

 the sides and at the tip ; the last ventral segment (enclosing the forceps) conspicuously expanded down- 

 wards, within it (when viewed in the direction of the axis of the body) three pieces, composing the forceps, 

 may be seen, with a Y-shaped incisure between them. Front, face, and occiput beset with whitish hairs ; 

 upper part of the occipital orbits with a silvery reflection. Antennae black ; third joint subcorneal at the base, 

 unsymmetrically prolonged in a stylo about as long as its basal portion, and ending in a microscopic joint 

 with a bristle. Halteres whitish-yellow. Legs black, the knees slightly reddish ; hind femora clothed on the 

 outer side with a short appressed whitish, moderately dense, tomentum, and with a fringe of long soft 

 hairs on the underside ; stiff hairs or spinules on the hind tibia? ; no long bristle at the end of the hind 

 metatarsus. "Wings hyaline, yellowish-brown at the root ; a spot of the same colour near the origin of the 

 second vein. 



Female. General colouring of the body greyish-black ; thoracic dorsum, scutellum, and abdomen clothed with a 

 short, appressed, rather rare, fulvous tomentum, not dense enough to conceal the ground-colour : the stripes 

 which this tomentum forms on the thorax of the male are almost (sometimes altogether) invisible here ; 

 a stripe of white hairs each side above the root of the wings, between the humerus and the post- 

 alar callus ; pleurae beset with white hairs : hind margins of the abdominal segments with more or less 

 distinct fringes of white hairs (more distinct than in the male) ; the fringe on the first segment broader 

 and slightly interrupted, and the erect hairs on the abdomen shorter and much less conspicuous than in the 

 male. Interval between the eyes rather broad on the vertex ; face and front clothed with a short, appressed 

 fulvous tomentum, the short, erect hair on the same parts having a dark appearance, but showing in some 

 specimens and in a certain light a silvery or yellowish reflection ; frontal and occipital orbits whitish ; the 

 orbits near the vertex dark. Antennae and legs as in the male. Wings hyaline, very little yellowish at 

 the root ; a stump on the fork of the third vein often, but not always, present. 



Length 6-8 millim. 



Eab. Mexico, Northern Sonora (Morrison). Three males, four females. 



A female specimen, somewhat larger (9-10 millim.), has the hind margins of the 

 abdominal segments without any white hairs, and even the scale-like hairs on the first 

 segment yellowish. I am not sure whether it is the same species. A. cyclops seems to 

 be variable as to the distinctness of the stripes on the thorax ; specimens in which they 

 are very distinct are comparatively rare. 



