138 ILB. E. E. ArSTE>' OlST IfEW DIPTEROUS INSECTS. [Jan. 17, 



SO that the outer extremity of the first posterior cell is Avide : 

 alulce rudimentary. 



Mysol Is., Malay Archipelago (Wallace): one specimen. 



The type of this species was described by Walker (Journ. Linn. 

 Soc. vii. p. 212) as being possibly the male of his species Baccha 

 purpuricola, the type of which is a female. The yellow face and 

 variegated abdomen of the present species, however, render its 

 identity with B. purpuricola absolutely impossible. This species 

 is clearly allied to Baccha moluccana, Doleschall (Xatuurk. Tijdschr. 

 Ned. Ind. xiv. p. 412, tab. iii. fig. 2), from Araboina, the abdomen 

 of which, as figured by Doleschall, is strikingly similar to that of 

 the present species ; the face of Doleschall's species is, however, 

 black in the middle and yellow on the sides, and he expressly states 

 that the scutellum is black. 



Baccha EEFULGENS, sp. n. (Plate I V". fig. 4, $ .) 



5 . Length 13 mm. 



Front, face, and cheeTcs metallic dark purple, thinly clothed with 

 pale pile ; facial tubercle not sharply defined. Antennce orange- 

 yellow ; third joint oval. Thorax and scutellum metallic purplish 

 violet, nearly bare ; postalar callosities brownish. The abdomen 

 spatulate from the commencement of the thii'd segment, thinly 

 clothed with short blackish pile ; the first two segments metallic 

 blackish, the remainder brilliant metallic pansy-purple. Le(/s _yellow; 

 posterior femora \\ith a faint indication of a narrow broMTiish ring 

 beyond the middle ; distal third of posterior tibiae and posterior 

 tarsi brown. Wings hyaline, with the costal border to the tip of 

 the thii-d vein (including the costal, subcostal, and marginal cells) 

 and a central area, which includes the basal cells, rather less than 

 the basal half of the submargiual cell, rather less than the basal 

 third of the first posterior cell and the basal two-thirds of the 

 discal cell, and faintly extends to the posterior margin at the tip 

 of the anal cell, brown : alulce of full size. 



Bouru Is., Malay Archipelago ( Wallace) : one specimen. 



This species is allied to Baccha purpuricola. Walker (Journ. Linn. 

 Soc. iii. [iv.] p. 129), from Key Is., but is distinguished at once by 

 the colour of its thorax. 



Baccha teiangulifeea , sp. n. (Plate lY. fig. 5, S ■) 



S 2 . Length 13 mm. ( $ 12| mm.). 



Front, face, and cheeks yellow, with short pale yellow pile ; a 

 narrow dark brown median stripe extending a little more than 

 halfway down the face from the antennas. Vertical triangle in 

 cJ shining black, very long and narrow, extending more than one- 

 third of the distance between the occiput and anteunje. I'ront of 

 5 with a brownish triangular spot immediately above the antennae ; 

 very narrow above, metallic black, with parallel sides for one half 

 its length from the occiput. Occiput dull black, poUinose, with a 

 fringe of glistening whitish hairs. Antennce orange, third joint 



