304 BULLETIN 31, UNITED STATES NATIONAL MUSEUM. 



EXPLANATION OF PLATES. 



[All the fip;iires are from nature, by the author.] 



PLATE I. 



1. MlCRODON FCSCIPENNIS Maoq., Irt, hind leg of male. 



2. MlCRODON IJALIOPTKKCS Loew ?, head of male. 



3. MlCRODON TRiSTis Loeu, wing; '.ia, hind leg. 



4. MlCRODON (jLoi'.osis Fabr., head of male. 



5. Chrysotoxtm DKRiVATUM Walker, wing; 5a, head of male; 56, hind leg; 5c, 



antenna- of four dilt'wrent individuals. 



6. CHRY.soTOXlhM, SJ). (PUIJESCKNS?). 



7. Paragi s nicOLOR Fabr., head of female. 



8. Paragus TIBIALIS Fallen, head of female. 



9. Para(;us bicolor Fabr., wing. 



10. Nausigastek punctulata Will., male; lOo, wing, var. 



