BACCHA. 1 23 



reaching to the oral margin, metallic black, sometimes steely ; 

 sides ot face yellowish poUiiiose ; cheeks orange-yellow, with a 

 blackish-browu spot in trout, more or less distinctly connected 

 with the facial stripe, sometimes indistinct in the $ . Front (in- 

 cluding vertical triangle in o ) '"ind face clothed with pale yellow 

 pile. Frontal triangle in 6 dusted with yellowish pollen above ; 

 front in $ , a little below the middle, with a triangular patch of 

 pale yellow pollen on each side, the apices of the triangles meeting 

 or narrowly separated in the median line. A distinct facial 

 tubercle and antenniferous process, the latter somewhat more 

 pronounced in the $ than in the c^ . A lunate spot on eacli side 

 of the antenniferous process metallic-violet. Antennae orange- 

 yellow; 3rd joint oval, arista brown, yellow at the base. Occiput 

 black, whitish j^oUinose, with a fringe of pale hairs. 'Thorax and 

 scutellum : in (5 metallic bronze-black, clothed with golden pile; 

 in J' metallic blue-black, clothed with shorter wjjitish-yellow pile ; 

 in the S ^ sometimes obscure yellowish vertical stripe <dn the 

 pleurae beneath the suture ; in the 5 , humeri and a similar vertical 

 stripe on the pleura) light yellow, the stripe with whitish pile. 

 General colour of the abdomen bronze-black witli yellow markings; 

 clothed with erect and rather long yellowish pile on the sides of 

 the first three segments, and elsewhere with appressed pile, blnck 

 on the black and whitish on the yellow portions; the sides of tlie 

 3rd and 4th segments in the J are so curled round ventral ly as 

 to miike the abdomen at the ti[) appear not more than double the 

 width of the 2nd segment at the base ; distal half of the abdomen of 

 the $ spatulate ; 1st segment reddish-yellow, brown on the hind 

 margin, sometimes wholly brown or bronze-black in the (5; 2nd 

 segment bronze in the S , sometiu)es reddish on each side at the 

 base, with a more or less distinct reddish-yellow transverse band 

 on the second sixth from the hind margin ; in some specimens 

 the 2nd segment is wholly bronze-black in the S , except the 

 posterior fifth, which is dull black ; 2nd segment in the $ metallic 

 black, with a reddish-yellow band on the second fifth fron) the 

 hind margin, and sometimes reddish-yellow at the base ; 3rd 

 segment in the c? bronze on the basal and dull black on the 

 apical third, with a quadrate yellow spot on each side in the 

 middle ; 3rd segment in the $ metallic black, with a yellow, some- 

 what triangular spot on each sule in the middle, the apices directed 

 outwards, and the bases inclined one towards another and some- 

 times narrowly meeting in the middle line in fro?it ; tlie posterior 

 side of each triangle concave ; 4th segment in the 6 bronze- 

 black, with a quadrate yellow spot on each side at the base, 

 occasionally somewhat obscure, but when distinct deeply emargi- 

 nate pf>steriorly, so that each spot shews a sharp angle jjrojecting 

 backwards on each side of the median line; 4th segment in the 

 $ metallic black, with a yellow longitudinal stripe on each side 

 of the median line, starting from the base and running the wlude 

 length of the seginent, and a broader yellow elongated spot 

 starting from the base of the yellow stripe on each side and 



