394 ME. F. W. EDWAEDS ON DIPTEEA 



Family Stkatiomyiid^. 



Subfamily Pacliygastrinae. 



Genus Evaza. 

 Evaza Walker, Proc. Linn. Soc. London, i. p. 109 (1857). 



6. Evaza impendens. 



Nerna impendens Walker, Proc. Linn. Soc. London, iv. p. 97 (I860). 

 Evaza impendens Kertesz, Ann. Mus. Nat. Hung. iv. p. 282 (1906). 



1 2 . Mimika Eiver, July 1910. 



This specimen agrees well both with Walker's type and Kertesz's description, 

 except that the thorax is scarcely at all shining. There appears to be no difference in 

 the punctuation of the thorax, however, so that the specific identity of our specimen 

 with JE. impendens is quite probable. The species is known from Celebes and the 

 Aru Islands. 



Genus Ptilocera. 

 Ptilocera Wiedemann, Nova Dipt. Gen. p. 7 (1820). 



7. Ptilocera violacea, sp. n. (PL XXXVIII. figs. 2 a, 2 h.) 



2 ?. Mimika Eiver, July 1910. [Type and faratype of the species.) 



Also 2 d , 1 ? in the British Museum Collection from the Aru Islands {A. B. 

 Wallace). 



2 . Head : front much excavated between the antennae and the ocelli ; shining 

 black, except for a small reddish patch just above the antennae and a pair of small 

 roundish silvery-poUinose patches at the margins of the eyes. Face shining black, 

 clothed with short white pubescence except on the central knob. Antennae with the 

 basal joint black, cylindrical ; second, third, and fourth joints reddish (in one specimen 

 the second joint is blackish), these three joints each much deeper than they are 

 long and together forming a sub-circular disc ; appendage of the fourth and lower 

 appendage of the fifth joints reddish, the remainder of the antennae black, except the 

 extreme tip, which is whitish. Thorax with four stripes of small iridescent scales 

 which are either emerald-green or purple according to the direction of the light ; the 

 outer and inner pairs are connected together at the front margin and again on the 

 scutellum, but the middle of the scutellum is without scales. Abdomen somewhat 

 shining, metallic blue ; small lateral longitudinal patches of white pubescence on 

 the second and third segments, fourth segment with a pair of transverse patches of 

 similar pubescence, which do not quite meet in the middle ; hind margin of the 

 fourth segment with a simple emargination. Legs : femora and tibiae blackish, 

 somewhat shining, with inconspicuous pale pubescence ; tarsi dark brown to yellowish 



