T. D. A. COCKERELL. 113 



very rich iu insects of tliis group, the several species being attached 

 to different genera or families of plants, especially Compositse. If 

 this view is correct, there is in the south a very rich field for in- 

 vestigation, which will yield results of great interest if the insects 

 are collected in adequate series, and their flower-visiting habits 

 recorded. 



In order to make the identification of the above four species easier, 

 a special table is presented : — 



FEMALES. 

 Hair on iuuer side of basal joint of hind tarsi black or fuscous (dark red in 



raphaelis) 1 ■ 



Hair on inner side of basal joint of hind tarsi ferruginous (dark in raphaelis:) . . .6. 



1. Thorax without black hair above; size rather large (Colo.) 



glenwoodeusis Ckll. 

 Thorax with conspicuous black hair above 2. 



2. Hair of middle of front of mesothorax black, of pleura largely black. 



melaiidri Ckll. 

 Hair of middle of front of mesothorax pale 3. 



3. Comparatively large species, of Colorado mysops Ckll. 



Smaller species, of the S. and E. States, and E. Mexico 4. 



4. Hair of thorax in front ochreous, this extending about as far back as front of 



tegulae (Elkhart, Indiana, from Mr. Lovell) simillima Rob. 



Hair of thorax in front greyish-white, this not extending so far back ; first 

 abdominal segment with green and purple tints 5. 



5. Facial quadrangle about square ; flagellum scarcely reddened beneath (Geor- 



gia; cotype) perplexa Cresson. 



Facial quadrangle conspicuously broader than long; flagellum strongly red- 

 dened beneath (Mexico) raphaelis Ckll. 



6. Thorax without dark hair above ; tegulse and flagellum beneath red. 



briiesi Ckll. 

 Thorax with dark hair above 7. 



7. Subbasal region of second abdominal segment not obviously punctured ; wings 



hyaline, not smoky or reddish ; the whole apical margin of fourth 



abdominal segment with black hair wlieeleri Ckll. 



Subbasal region of second abdominal segment obviously punctured, especially 

 at sides ; apical margin of fourth abdominal segment with light hair, 

 except perhaps in middle 8. 



8. Scopa of hind tibisB thin, little plumose ; abdomen longer, .wickhaiiii Ckll. 

 Seopa of hind tibiae thick, strongly plumose ; flagellum red beneath 9. 



9. Hair of pleura entirely pale (Georgia ; cotype). coinninnis Cresson. 



Hair of pleura black, with some white intermixed (Mexico). 



raphaelis Ckll. 



iHelissotles iiiicrosticta Ckll. 



The range of this species is greatly extended by a % from Color- 

 ado in the Cresson collection. It shows rather more abundant black 



TRANS. XU. ENT. SOC. XXXII. (15) FEBRUARY, 1906. 



