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昆^ 學雜誌 第參卷 第壹號 



longer than the antenna itself. Proboscis quite long, the sucking suriace 

 broad, the palpi small, blunt conical, the oral margin oval. Compound 

 eyes pubescented or naked, in the male holoptic, vertex shorter or longer 

 than the touched portion of the compound eyes, in the female widely- 

 separated (dichoptic;, vertex as wide as the half breadth of the front 

 between the antennae. Thorax somewhat vaulted, on the side not 

 yellowish striped. Scutellum waxy yellow. Wings broad, hyaline, 

 without markings, the 3rd longitudinal vein straight or somewhat curved 

 into the first posterior cell, opens in or near the apex, the cross-vein at 

 about of the discoidal cell near the base, the bend of the 4th longitud- 

 inal vein with an appendage ； the marginal cell open, the discoidal cell 

 as long- as the first posterior cell, the latter with the apical angle always 

 acute. Alulets distinct, calypteres large, roundish. Abdomen broader 

 than the thorax, yellowish banded, the first band often interrupted, on 

 the lateral sides being indistinctly ridged. Lee^s slender, the femora not 

 thickend, the posterior tibia somewhat curved in the middle. 



We have in Japan the following 20 species and they are classified 

 under the following subgenera : 



Table of subgenera. 



1. Vertex in the male as long as or longer than the touched portion 

 of the compound eyes; the anterior ocellus much smaller than 

 the posterior ones and much separated from the posterior ones. 



Macrosyrphus n. 



一 Vertex shorter thah the touched portion of the compouna eyes; 

 the anterior ocellus scarcely smaller than the posterior ones and 

 not much separated from the posterior ones or nearly in equi- 

 lateral 2 



2. The upper facets of the compound eyes in the male much larger 

 than those of the lower part ； 3 ocelli nearly in equilateral 

 triangle Lasiophticus Rond. 



一 The upper facets of the compound eyes in the male not much 

 larger than those of the lower part 3 



3. rhree ocelli making a longer triangle than equilateral ； the 3rd 

 longitudinal vein opens before tne apex Syrphus n. 



