Kahl: The Dipterous Genus Leucophenga Mik. 391 



are all strong; the upper reclinate fronto-orbital is the longest and strongest bristle 

 of the head and situated midway between the inner vertical and the lower reclinate 

 fronto-orbital and a little higher up than the lower ocellus; the outer vertical bristle 

 is stronger than the inner one, which is of the size of the lower reclinate fronto- 

 orbital, and this latter bristle is situated further from the proclinate fronto-orbital 

 than in any of the previous species; behind the regular pair of strong ocellar bristles 

 are seen two pairs of minute, proclinate setulae; the postvertical bristles strong, 

 decussate, but smaller, however, than any one of the fronto-orbital, vertical, or 

 ocellar bristles; one of the setulse of the lower occipito-orbital fringe is more robust 

 and bristle-like; the uppermost setula of the occipito-orbital fringe is stronger and 

 diverging from the other setulae in the fringe; along the posterior oral margin two 

 small, distinct bristles, far apart from each other; the usual very minute setula 

 between the sternopleural bristles present; the anterior dorso-central bristle only 

 one-half the size of the posterior but of the same size as the prescutellar pair, which 

 is situated hardly closer to the scutellum than is the posterior dorso-central; on 

 the humerus there are, besides the minute, hair-like setulae, two or three bristles, 

 the middle one of which is the longest, but not as long or strong as the noto-pleurals; 

 the presutural and the anterior supra-alar distinct, well developed, and of the size 

 of the longest humeral; the posterior postalar is well developed; the apical pair of 

 scutellar bristles cruciate, the lateral pair diverging and longer than the former; the 

 apical scutellar bristles are much closer to each other than either of them to its 

 nearest lateral bristle; two very minute and delicate prothoracic setulae may be 

 detected immediately above the front coxae; all bristles and setulae black. 



Habitat: Cameroons, West Africa, eight specimens collected at 

 Lolodorf, Oct. 29, 1913, by A. I. Good. The type bears the label 

 Carn. Mus. Ace. No. 5264; seven designated as paratypes each have 

 the label Carn. Mus. Ace. No. 5266. 



This species is, indeed, an ambiguous Leucophenga, and I refer it to 

 this genus, because the costa reaches only to the apex of the third vein; 

 its strong postverticals are those of Drosophila. The cross-vein, 

 separating the discal and second basal cells, is distinct in Phorticn 

 and Stegana, but missing, or obliterated in Leucophenga, Drosophila, 

 Scaptomyza, and other genera. Instead of the cross-vein there is a 

 more or less distinct, transparent, or pale, mark, which even extends 

 across the first basal cell and this mark follows the bend of the wing', 

 in amhigua this mark is more pronounced and has in certain lights 

 almost the appearance of a cross-vein. 



It is worth while to call attention here to the fact that the two fol- 

 lowing species, originally described as Drosophila belongs to the genus 

 Leucophenga. 



12. Leucophenga insulana Schiner. 



Drosophila insulana Schiner, Reise der Novara, Diptera, (1868) p. 240; from 

 "Milu (einer der Nikobaren)." 



