190 



4. Thorax more greyish with three somewhat conspicuous 

 grey median stripes, abdomen with rather large yellow - 



haired median triangles ...humilis, Coquillett. 



44. Thorax at the anterior half* dusted with grey, abdomen 



without distinct triangles iyoensis. Shir. (n. sp.) 



22. Black species with white-haired sciitellum and white-haired 

 bands on abdomen. 

 3. Wings clear. 



4. Tibiae covered with very thick white pubescence, abdomen 



with five white-haired binds 



quinquccinctus, Ricardo. 



44.. Tibiae covered with rather sparse white pubescence, abdomen 



with six white-haired band-. — sexnntus, Ricardo. 



33. Wings tinged with brown on fore border, abdomen with only 



two distinct white bands biclnctus, Ricardo. 



B. Frontal stripe with one callus which is almost always prolonged 

 towards the vertex by a more or less nrrrow line. 

 I. Abdomen with one or more continuous stripes. 



2. Species with a broad reddish yellow median stripe on the 



abdomen. ( Medium-sized) aurotcstacats, Walker. 3 



22. Species with three narrow greyish yellow stripes on the ab- 

 domen. ( Medium-sized) abbreviates, BigoL 



222. Species with a rather inconspicuous narrow yellowish median 

 stripe on the abdomen. (Sma\L*£ized) f ..miya&ei, Shir. (n. sp.) 

 II. Abdomen with one or more interrupted stripes. 

 2. Species with median spots on the abdomen. 



3. Abdomen covered with black pubesence, frontal stripe narrow 

 with narrow callus. 

 4. Thorax with three distinct but narrow yellowish stripes, 

 antennae reddish, tibiae reddish brown, yellow median 



spots very small okinaivanus, Shir. (n. sp.) 



44. Thorax with very faint stripes, antennae blackish tibiae 



