196 Annals Entomological Society of America [Vol. IX, 



Myopa. 



In the following table of the species in my collection I have 

 depended largely upon color; the color of the hair is very 

 important; but the amount of reddish on thorax and abdomen 

 in certain species is doubtless variable. 



1. Wings with distirict dark clouds over the cross- veins; abdomen black-haired. 2 

 Wings without clouded cross- veins 4 



2. Face with rather short hair; a cloud in first posterior cell, which is closed, 



small species melanderi 



Face with long white hairs, forming a fringe below; first posterior cell open. .3 



3. Face with several small black spots on each side, dark clouds in both first 



and second posterior cells willistoni 



Face at most with a reddish spot each side above, no clouds in posterior cells. 



vicaria 



4. Thorax and abdomen with short appressed white hairs 5 



Thorax and abdomen with black hair 6 



5. Abdomen mostly reddish; costal cell not much darkened, vesiculosa var.varians 

 Abdomen mostly black; costal cell very plainly blackish vesiculosa 



6. The hairs on thorax above are hardly one-half as long as the arista; abdomen 



also with very short hair 7 



The hairs on thorax above as long as the arista; abdomen also with long 

 hair .■■•9 



7. Abdomen wholly red; hairs of body are extremely short seminuda 



Abdomen largely black 8 



8. Abdomen reddish on sides and behind; fifth segment not divided by a median 



pollinose pale streak plebeia 



Abdomen not reddish; fifth segment with a median stripe of pale pollen. 



virginica 



9. Abdomen mostly black longipilis 



Abdomen mostly red 10 



10. Proboscis very long, the second joint as long as femur I, the last joint as 



long as the second clausa 



Proboscis with the second joint only about two-thirds as long as the front 

 femur, the last joint a little shorter than second rubida 



Myopa vesiculosa vSay. 



This species is readily known by the white hair of body; it 

 occurs both East and West, specimens are before me from Wash- 

 ington State, and the conjuncta of Thompson from California 

 may possibly be the same species. 



Myopa vesiculosa var. varians n. var. 



Structurally like the typical form, but rufous throughout, and 

 the wings lack the dark cloud through the middle area. The antennas 

 are a trifle shorter, but this may not be constant. 



From Lincoln, Neb. Sent me by Mr. P. R. Jones as his idea 

 of Myopa clausa. 



Myopa vicaria Walk. 



The description of M. pilosa Will, fits this species very well, 

 but I have not seen any Californian examples and it may be 

 distinct. 



