142 ITR. E. E. AtlSTEK Olf NEW DIPTEEOUS I>'SECTS. [Jan. 17, 



to decide whether they really belong to a new species ; I therefore 

 regard them provisionally as a variety of B. pulchrifrons. 



Baccha fallax, sp. n. (Plate IV, fig. 12, cJ.) 



d . Length 11 mm. ; wing, length S| mm, width across the 

 centre 2| mm. Yery closely I'esembling B. pulchrifrons; differing 

 as follows : — front, and broad median facial stripe reaching to the 

 oral margin, metallic black, not steely; sides of the /wcf, including 

 upper portion, and cheeks deep yellow ; antenniferous process 

 considerably smaller, when viewed from above, and no trace of 

 metallic violet spot on the side ; thorax and sciiteUmn more bronzed ; 

 pileural stripe orange, much more conspicuous, and rising higher on 

 the sides of the dorsum ; first segment of the abdomen pure yellow ; 

 second segment considerably narrower, longer, and wholly bronze- 

 black, except the basal angles, which are yellow; the yellow markings 

 on the third and fourth segments entirely resembling those on the 

 corresponding segments in the $ of B, pulchrifrons, and not as in 

 the S of that species ; wings longer and narrower ; except at the 

 base, uniformly suffused with bro^^Ti, not darker in the middle ; 

 apical spot above the third vein reduced to a mere line, so as to 

 appear as a simple continuation of the stigma : alidce long and 

 rather narrow, with a straight posterior edge. 



Ceylon {Lieut. -Colonel Yerbury) : two specimens, both males. 

 The type was collected at Haycock Hill, near Galle, April 27, 

 1892 ; the second individual at Kandy, May 30, 1S92. 



Owing to the deceptive similarity between the markings on the 

 abdomen of this species and those on the abdomen of B. pulchri- 

 frons 2 > these specimens would certainly be regarded as males of 

 the latter if regard were not paid to the differences enumerated 

 above. 



Baccha amphithoe, "Walker, List. Dipt. iii. 549. (Plate IV. 

 fig. 2, 2 .) 



Walker's type is from the " East Indies," i. e. Mulmein, 

 according to the Museum register, coll. Archdeacon Clerk, The 

 Museum collection also contains another specimen from Sarawak, 

 collected by Wallace (Walker, Journ. Linn. Soc. i. 125). Walker's 

 type, however, is a mere fragment, the sex of which it is impossible 

 to determine, and was minus its head when Walker described it. 

 I therefore avail myself of the opportunity presented by the 

 acquisition of three specimens from Ceylon, contained in a collection 

 of Diptera recently brought home by Lieut.-Colonel Terbury, to 

 re-describe this species. The specimens from which this re- 

 description is drawn will be marked and placed in the Museum 

 collection. 



S $ , Length : J 10 mm., 5 10 to 11 mm. Face and cheeks 

 yellow. A sharply-defined black median stripe on the face, from 

 antennae to mouth, becoming somewhat indistinct before reaching 

 the mouth in the $ ; sometimes with a metallic bluish sheen. A 

 low facial tubercle. Front metallic black iu both sexes, and yellow 



