﻿THE ENT01^10L0<ö!CA!L MAGAZINE Vo!. II. 135 



Face beneath conically produced, the facial tubercle in the middle some- 

 what keel-like elevated. Vertex in the female much narrower tlian the 

 half breadth of the front between the antennae. Antennae small, the 3rd 

 joint blunt conical, the arista from near the base, the first joint scarcely 

 shorter than the 2nd, with many short bristles, the 3rd as long as the 

 first and 2nd taken together, the arista near the base, longer than the 

 antenna itself, finely pubescented. Compound eyes bare. Thorax on 

 the sides yellow striped. Wings broad, the 3rd longitudinal vein opens 

 before the apex, in the middle much curved into the first posterior cell; 

 the bend of the 4th vein without appendage (only a fold may be seen) ； 

 the cross-vein at about ^ of the discoidal cell near the base. Abdomen 

 on the sides scarcely ridged ； hypopygium on each side with a hook-like 

 projection. Ihe larvae of this genus are not yet known, but they are 

 most probably aphidivorous. We have in Japan and Formosa only two 

 following species. 



1. Wings brownish infuscated, thorax in the disk brownish pubescented. 



fumipennis Sack. 



2. Wings grayish or grayish yellow, hyaline, thorax in the disk yellow 



pubescented ericetonim F, 



1. Asarcina ericetorum F. (pi. iv, tig. i， i".) 

 Syrphus ericetcrum F. Ent. Syst. IV, 287, 34 (1794). 

 Syrphus Salvias F. Ent. Syst. IV, 306， 105 (1794). 



Didea Macquarti Dol. Nat. Tijds. Ned. Ind. XIV， 408 PI. 10, 

 f. 1 1(1856). 



Syrphus incisuralis Macq. Dipt exot. Supl. 5, p. 94, 56 (1855). 

 Ancylosyrphus Salivae Bigot. Bull. ent. Fr. P. LXVIII (1882). 

 Syrphus porcinus Coq. Proc. Nat. Mus. U.S.A. p. 322 (1898). 

 Asarcina ericetorum var. formosae Bezz, Ann. Nat. Mus. Hung. 

 6, P. 495 (1908). 



Yellow. Face whitish yellow, vertex fuscous, on the sides narrowly 

 yellow, with black hairs. Antennae yellow, the 3rd joint on its back 

 brownish ； the antennal-process yellow, arched above by a short bluish 

 bar ； cheeks behind blackish. Proboscis black, at the apex yellowish. 

 Thorax aeneous black, yellowish pubescented ； scutellum yellow, fuscous 

 pubescented, the hairs on the hind margin beinp- vellovvish. Wings 



