408 ME. P. W. EDWAEDS ON DIPTEEA 



has the apex of the hind-femora and the base of the hind-tibise dark. These 

 differences may or may not be of specific value. There appear also to be slight 

 differences in the male hypopygia. 



37. PSILOPUS EGENS. 

 Psilopus egens Walker, Proc. Linn. Soc. London, iii. p. 92 (1859). 



1 6 . Mimika River, July 1910. 



In this species the bristle on the underside of the second joint of the antennae is 

 much longer than usual, being fully two-thirds as long as the depth of the head. 

 The only specimen previously in the British Museum Collection was Walker's type 

 from the Aru Islands. 



Family S Y R p H i d ^. 

 Subfamily Syrphinse. 



Genus Asaekina. 



Asarkina Macquart, Dipt. Exot. ii. 2, p. 77 (1842). 

 Asarcina Kertesz, Cat. Dip. vii. p. 94 (1910). 



38. Asarkina iEGROTA. 



Eristalis cegrotus Fabricius, Syst. Antl. p. 243 (1805). 

 1 3 . Mimika River, July 1910. 

 1 d , 2 ? . Wataikwa River, Aug. 1910. 



This species is widely distributed over the Oriental and Australasian regions, but 

 these are the first specimens received by the British Museum from New Guinea. 



39. Asaeeiwa biroi. 



Asarcina biroi Bezzi, Ann. Mus. Nat. Hung. vi. p. 498 (1908). 



"iDidea macquarti Doleschall, Nat. Tijdschr. Ned. Ind. (3) iv. p. 408 (1857). 



1 5 . Wataikwa River, Aug. 1910. 



The British Museum Collection previously contained a pair from the Aru Islands and 

 a female from Mysol {A. B. Wallace), all three being determined as A. macquarti. 



40. Asarkina ericetorum, var. papuana. 



Syrphus ericetorum Fabricius, Species Insect, ii. p. 425 (1781). 



Asarcina ericetorum, var. jjapuo.na Bezzi, Ann. Mus. Nat. Hung. vi. p. 499 (1908). 



1 ? . Wataikwa River, Aug. 1910. 



This is the first specimen of this variety received by the British Museum. 



