SYNOPSIS OF NORTH AMERICAN SYRPUIDiE. 91 



times exteiidiug over tbe whole tibiie ; IVoiit and middle tarsi brownish, 

 except the base and ti]); hind tarsi on the three intermediate joints 

 blackish ; the metatarsi also sometimes blackish. Wings with a grayish 

 tinge ; stigma brownish ; veins ou basal part red ; cnrvature of the third 

 vein more shallow than in D.fuscipes. 



Three specimens from the White Mountains (Dr. George Dimmock, 

 150C) and thirty-three from Oregon and Washington Territory ; also, 

 three from California. In some of the Western specimens the front and 

 middle tibite have a small brownish ring. 



This species corresponds to D. ahieti of Europe. 



XANTHOGRAMMA. 



Xantliogramma Scbiner, Wien. Eut. Mouatsclir., iv, 215, 1860. 



Moderately large, nearly bare, species, black, with yellow markings 

 on head, thorax, and abdomen. Antennae shorter than the head, third 

 joint oval, arista basal, bare. Face yellow, tuberculate. Eyes bare, 

 contiguous in the male; front long in the female, narrowed above. 

 Thorax with yellow lateral stripes. Scutellum yellow, its base black. 

 Abdomen more than twice as long as, and wider than, the thorax ; ellip- 

 tical or with the sides nearly parallel, not club-shaped. Legs simple, 

 slender. Wings as in >yrphufi^ the third vein often gently curved into 

 the first posterior cell. Type of genus X. ornuta Meigen, Europe. 



This genus cannot be sharply distinguished from Syrphns, as, except 

 in aeqiialis and flavipes, the lateral dorsal stripes are not much more 

 conspicuous than in certain species of Syrphus. 



TABLE OF SPECIES. 



1. — Dorsum of thorax before the scntelhim with two coalescent light yellow spots; 



wnngs with a browu anterior margin aequalis 



Dorsum of thorax without yellow spots on the hind margin ; wings not brown in 



front 2 



2. — Pleura3 with light yellow spots flavipes 



Pleurae without distinct light yellow spots 3 



3. — The yellow band on the second abdominal segment attains the lateral margin. 



emarginata 

 The yellow band of the second segment is separated by a distinct black interval 



from the lateral margin 4 



4. — All the cross-bands of abdomen broadly interrupted divisa 



All the cross-bands not broadly interrupted felix 



Xanthogramma felix. 



Xaii iJiogramma felix Osten Sacken, Bull. Buff. See. Nat. Sci.,ili,G7; Cat. Dipt., 

 12G and 247, note 215 ; Williston, Proc. Phil. Soc, xx, 311. 



Habitat. — Illinois, Xew York (O. S.), Connecticut! 

 " 9 . Length 9.5 to 10. 5™™. Face and cheeks yellow (in all my speci- 

 mens, except one, the face has the brownish-red tinge, which the faces 



