6 PROCEEDINGS or THE NATIONAL MUSEUM. vol.60. 



3. Posterior spiracles with two slits ; protuberance roughly granular. 



(No. 16) (Leucostoma) Dionea atra Townsend. 

 Posterior spiracles with three slits 4 



4. Spiracles almost on the florsum ; the pupai'ium large. 



(No. 17) Microphthalma disjuncta Wiedemann. 

 Spiracles on the longitudinal axis line 5 



5. Spiracles somewhat cylindrical ; widely divergent ; segmental lines distinct. 



(No. 18) Exorista lobeliae Coquillett. 

 Spiracular protuberances close together 6 



6. Puparium enlarged on caudal half ; spiracles contiguous at the base. 



(No. 19) Gymnosoma fuliginosa Desvoidy. 

 Puparium slightly pointed on caudal end ; spiracles touch at the base ; from 

 above, they are separated by a V-shaped space. 



(No. 20) OcyT)tera carolinae Desvoidy. 



7. Segmentation very distinct; a prominent elevation between the spiracles. 



(No. 21) Exorista confinis Fallfe. 



Segmentation not distinct 8 



S. Spiracles distinctly raised above the surface 9 



Spiracles very slightly raised above the surface 10 



9. Spiracles located at the apes of the puparium ; slits not located on definite 



ridges (No. 22) Trichopoda pennipes Fabricius. 



Spiracles located below the apex ; slits located on a definite narrow ridge. 



(No. 23) Trichopoda lanipes Fabricius. 



10. With four slits 11 



With three slits 13 



11. Spiracular plates very small, on the longitudinal axis line. 



(No. 34) Phorocera saundersii Williston. 

 Spiracular plates larger, not on the longitudinal axis 12 



12. Spiracular plates quite close together ; second slit from the bottom rather 



long (No. 25) Exorista boarmiae Coquillett. 



Spiracular plates quite small and widely separated; second slit from the 

 bottom is S-shaped (No. 26) Hyphantrophaga hyTjhantriae Townsend. 



13. Spiracles widely separated; a high elevation between the spiracles; elevation 



much wider at the bottom and pointed on both sides. 



(No. 27) Exorista eudryadae Townsend. 

 Spiracles widely separated; a large elevation between and below the plates; 

 the elevation notched above on each side. 



(No. 28) Frontina frenchii Williston. 

 Not as above 14 



14. Spiracles close together on the longitudinal axis line ; a transverse, elliptical 



elevation with pointed ends at the base of the spiracles. 



(No. 29) Linnaemyia fuMcauda Walton 

 Spiracles well separated ; tkree distinct lobes ; only a slight elevation below 

 spiracles. 



(No. 30) Frontina aletiae Riley ; Frontina archippivora Williston. 



GaOUP E. 



KEY TO THE SECTIONS. 



End of puparium with a large rounded tubercle Section 1 



End of puparium without a large rounded tubercle Section 2 



