191 1] Johnson — Dipterous Genera Proposed by Billberg 73 



Fig. 8. HydropkoTus ampledens sp. no v. side of abdomen of male. 



9. " canescens Wheeler, front femur and tibia of male. 



10. " breviseta Thomson, front tibia of male. 



11. " " " upper view of tip of left middle tarsus, 



male. 



12. " agalma Wheeler, upper view of tip of middle tarsus, male. 



13. " ampledens sp. nov., part of front femur and tibia of 



male. 



14. " philombrius Wheeler, front femur and tibia of male. 



15. Diostracus alga sp. nov., side view of male. 



16. " " " front view of head of male. 



17. " " " antenna of male outer side. 



18. " " " wing of male. 



NOTES ON THE DIPTEROUS GENERA PROPOSED BY 

 BILLBERG IN HIS ENUMERATIO INSECTORUM ^ 



My attention has been recently called to this work by Mr. 

 Henry L. Viereck who was endeavoring to locate some genotypes 

 in the Hymenoptera. A copy of this rare book was presented 

 to the library of the Boston Society of Natural History by Mr. 

 Samuel H. Scudder. In looking over the pages (112-123) 

 pertaining to Diptera I find the following generic names : 



"Tichodartha Eg. ^ — Mosillus Ltr., — Musca 01." No species 

 are mentioned. 



Under "1 Divis. alis divaricatis, 1 subdivis. antennis capite 

 medio brevioribus," page 118, appears the following: — 



"Blera Eg. — Eristalis Flln.— Syrphus Fbr. Ltr.— Musca 01. 

 fallax Svec. Linn. coemiteriorum Svec. Linn." 



Recognizing Cynorhina Will. (1886) as has been done by Verrall, 

 (Brit. Flies, VIII, 590) Musca fallax Linn, becomes the 

 type of Blera, or considering Cynorhina to be a synonym of 

 Criorhina Meigen, 1822, and ignoring Penthesilea Meigen, 1800, 

 Criorhina also becomes a synonym of Blera. Musca camiteriorum 

 Linn, is a doubtful species considered by some to be the same as 

 Chrysog aster solstitialis Fall. 



"Dones Eg. — Doros Mgn. Ill — Syrphus Auct. Pier. — Scaeva 

 Flln.— Musca el [01]. 



> Enumeratio Insectorum in Museo, Gustav Johann Billberg. [Holmiae] Typis Gadelianis 

 Gadel, 1820. 



* Eg. " Auctor hujus opens." 



