398 LIST OF DIPTERA. 



black, clothed with short black bristles ; second joint about half the 

 length of the first : chest dark gray, with a tawny tinge, grayish 

 tawny towards the sides, which, like the breast and the hind chest, 

 are hoary ; sides and hind part of the chest beset with black bristles : 

 abdomen gray, hoary beneath, tapering from the base to the tip, 

 thinly clothed with short white hairs, and with a tuft of long white 

 hairs on each side of the base, narrower than the chest, and about 

 twice its length ; segments from the third to the fifth successively 

 decreasing in length ; sixth and following segments of nearly equal 

 size ; ninth segment long, slender, black, shining : legs black, 

 clothed with pale yellow hairs, and beset with some black bristles, 

 which are most frequent on the feet ; claws black ; foot-cushions 

 ferruginous : wings pale brown ; wing-ribs ferruginous ; veins 

 black, piceous towards the base ; poisers tawny. Length of the 

 body 12 lines ; of the wings 18 lines. 



Group VII. Erax, Macquart. 



Asilus macrolabis, Wied. Auss. Zweif. i. 458, 51. 

 a. Georgia. From Mr. Abbot's collection. 



Asilus labidophorus, Wied. Auss. Zweif. i. 459, 52. Erax labido- 



phorus, Macq. Dipt. Exot. i. 2, 110, 7. 

 a. Brazil. 



In one example of this species the vein between the submarginal 

 areolets has a fork at its base in one wing, but not in the other. 



Asilus aestuans, Linn. Syst. Nat. ii. 1007, 5. Annan Acad. vi. 413, 

 95. Fabr. Syst. Ent. iv. 379, 8. Ent. Syst. iv. 379, 14. 

 Wied. Dipt. Exot. i. 200, 32. Auss. Zweif. i. 467, 63. Dasy- 

 pogon aestuans, Fabr. Syst. Antl. 164, 2. Erax aestuans, Macq. 

 Dipt. Exot. i. 2, 115, 19. 



a. Delaware. Presented by E. Doubleday, Esq. 



Asilus niger, Wied, Dipt. Exot. i. 196, 26. Auss. Zweif. i. 460, 



53. 

 a. Georgia. From Mr. Abbot's collection. 



Asilus fuscus, Wied. Auss. Zweif. i. 465, 59. Erax fuscus, Macq. 



Dipt. Exot. i. 2, 112, 11. 

 a. Brazil. From Mr. Mornay's collection. 





