438 K. OSTEN-SACKEN 



vSyn. Didea Ellenziederi Dolesch. 2 Bijdr. 31, Tab. X, f. 2 (Amboina). 

 Syrph-ias fascipennis Macq. H. N. Dipt. I, 537 [Macq.]. 

 SyrpliTis irLflrmixs Rond. Ann. Mus. Civico, vn, 423 (Borneo) ! 



The antennae vary in darkness and are sometimes nearly 

 black ; the hyaline space near the root of the wings is someti- 

 mes nearly obsolete. In the female from Sumatra the two yellow 

 spots on the second abdominal segment are coalescent and form 

 a continuous crossband ; this would answer the S. infirmus 

 Rond., the type of which is also a female ; the yellow spot on 

 each side of the last abdominal segment, mentioned in the des- 

 scription of the latter, is also present in my specimen. 



Syrphus salviae (Fab.) Wied. Auss. Zw. II, 122 (Java). 



?Syn. I3idea ]Vi:acq.u.arti Dolesch. 2 Bijdr. 32, Tab. X, f. 1 (Amboina) ! 



One (/", one 9, Ternate 1875; one 9 Kandari, Celebes, Apr. 

 1874; one 9 Hatam, N. Guinea, June 1875 {Beccavi). 



Wiedemann describes the face as yellowish, the hind tibiae as 

 yellow ; Doleschall the face as black, the hind tibiae likewise. I 

 have both forms among my specimens, which in other respects, 

 do not show any difference, but these specimens are not nume- 

 rous enough to enable me to decide whether these characters 

 are sexual; I therefore assume the synonymy with a doubt. 



Syrphus nectarinus Wied. Auss. Zw. II, 128 (China). 



Syn. S. alternans Macq. D. E. 11, 2, 89 (East-Indies) and Suppl. IV, 149 (Au- 

 stralia). 

 (?) S. triligatus Walk. J. Pr. Lin. Soc. I, 19 (Mt. Ophir). 



Two spec. 0^9; Ternate 1875; Java 1874 (Beccari). 



(?) Syrphus confrater Wied. Auss. Zw. II, 121 (China). 



One c/', one 9 ; Mt. Singalang, Sumatra, July 1 878 ; one 9 , 

 Hatam, N. Guinea, June 1875 (Beccari). 



Type of S. rihesii^ S. americanus etc. The description agrees, 

 except that the thorax is said to be metallic-blue, instead of 

 greenish. However the species of this group require a much 

 closer description than that of Wiedemann. 



