Afiican SjKcies of (lie Genus C'hrysops. 509 



a fifth specimen from the shore of Lake Victoria, in Buddu, 

 1903 [Sleeping Sickness Commission of the Royal Society, 

 per Colonel David Bruce, C.B., R.A.M.C., F.R.S.). 



Of the African species ah'eady described, Chrysops funehris 

 appears, so far as may be judged from the description, most 

 nearly to resemble C. confluens, Lw., irom the Cape of Good 

 Hope, from which, however, it may at once be distinguished 

 by the slender antennae, single frontal callus, and very 

 different wina:-marking:s. 



Chrysops silacea, sp. n. 



? . — Length (17 specimens) 8 to 10 mm.; width of head 

 2^A to 3 ram, ; width of front 1 mm.; length of wing 7^ to 

 9^ mm. 



Head yellow ; thorax Hack or blackish hrown, with yellow 

 longitudinal stripes ; scutellnm ochre-yellow, median portion 

 of extreme base hlack ; abdomen ochraceous, upper side marked 

 on basal half icith two longitudinal black stripes, not reaching 

 hind margin of third segment, and sometimes not extending 

 beyond second ; distal portion of iving from base of third vein 

 infuscated, transverse band inconspicuous, reduced to a small 

 dark blotch extending from base of third vein to posterior 

 upper angle of fifth posterior cell; legs ochraceous, front tarsi 

 and tips of middle and hind tarsi dark brown. 



Head rather broad, dark brown on vertex, elsewhere 

 clothed with ochre-yellow pollen, except on frontal callus, a 

 mark above base of each antenna, the facial tubercles, and 

 a small dark brown spot on the jowls below each eye ; frontal 

 callus of moderate size, three fourths as wide as the front 

 and well separated from the eye on each side, not highly 

 polished, edged with brown at the sides or sometimes all 

 round the upper curved margin ; facial tubercles highly 

 polished, elliptical in shape, occupying lower two thirds of 

 face and extending nearly to margin of buccal cavity, 

 separated from each other by a narrow stripe of yellow 

 pollen ; often only the upper portion of the poUinose stripe 

 is present, when the tubercles coalesce below and assume 

 the ajjpearance of a single elongate cordate tubercle, which 

 extends to the lower margin of the face ; front, except on 

 callus, clothed with short brown hair, densest on vertex ; 

 sides of face and lower surface of head clothed with pale 

 golden hair ; palpi lanceolate, widest part of moderate 

 breadth, thinly clothed with minute yellowish hairs ; 

 antennce 3| mm. in length, dark brown, basal portion of 

 slender first joint tawny ochraceous. Thorax clothed with 



