20 



2. Proboscis destitute of a white ring near the middle 3. 



Proboscis marked with such a ring, bases of tarsal joints white. 



twniorlnpichus Wied. 



3. Bases of tarsal joints distinctly white 4. 



Bases of tarsal joints never white 5. 



4. Mesonotum marked with four stripes of silvery scales fasciutus Fabr. 



Mesonotum destitute of such stripes: 



Fifth joint of hind tarsi white Irfnintus Wied. 



Fifth joint, except its extreme base, dark l>rown siimulans Walk. 



5. Last two joints < if hind tarsi never white 6. 



Last two joints of hind tarsi snow white jwsticaius Wied. 



6. Abdomen marked with a cross band of whitish scales at base of each segment. 



impiger Walk. 

 Abdomen never marked in this manner, hut witli a cluster of whitish scales at 

 front angles of some of the segments triseriatus Say. 



7. Proboscis marked with a distinct whitish ring near the middle, tarsi white at 



sutures of the joints. ._ 8. 



Proboscis destitute of a whitish ring near the middle 9. 



S. Tarsal joints white at liases only perturbcms Walk.' 



Tarsal joints white at both ends tarsalis Coq. 



9. Tarsi white at bases of joints 10. 



Tarsi never white at bases of the joints 12. 



10. Mesonotum never marked with stripes of silvery .scales 11. 



Mesonotum marked with four stripes of silvery scales, first tarsal joint never 



marked with a whitish ring near the middle signifer Coq. 



11. First tarsal joint marked with a whitish ring near middle of each. 



e.rcrncicms Walk. 

 First tarsal joint destitute of such a ring e.rcitans Walk. 



12. Petiole of submarginal cell less than one-third of the length of that cell. 



pungens Wied. 

 Petiole of submarginal cell at least almost one-half of the length of that cell. 



consohrinns Desv. 



(It) UNRECOGNIZED SPECIES. 



annulatuH Schrank. This European species was credited to our fauna by Osten 

 Sacken. The description agrees fairly well with specimens which I have identified 

 as excitant, Walker, except that in the latter there is no white ring on the femora 

 toward their apic(!S. 



boscii Desv. Probably a rubbed specimen of pungens. 



nigripes Zett. Black, the legs of the male dark yellow, hairs of pleura of female 

 gray, a band of white scales at base of each segment of her abdomen. 



rubidus Desv. The description was apparently founded on a rubbed specimen of 

 Psorophora ciliata. 



testaceus v. d. Wulp. Is probably a somewhat injured example of consobrinus. 



incident Thomson. Is evidently a synonym of impiger Walker. 



bigoti Bellardi. According to the figure and description, the bands of black scales 

 are at the bases oi the abdominal segments; in the recognized species these bands are 

 always at the apices of the segments. In other respects this species must greatly 

 resemble j:>ungens. 



cubensis Bigot. Apparently founded on a badly rubbed specimen of pungens. 



frater Desv. This name was proposed for the Cide.v fasciatus of Wiedemann, under 

 the impression that this is not the same species as the one described by Fabricius 

 under the same name. It seems quite certain, however, that the word "proboscis" 

 in Fabricius' description was simply a lapsus for "palpi," and with this emendation 

 the two descriptions agree very well. 



mexicana Bellardi. Is evidently a synonym of posticatus. 



provocans Walker. Is probably a synonym of stimulant. In some specimens of 

 this species the light color at the bases of the tarsal joints is very indistinct. 



lerritans Walker. Is apparently a synonym of pungens. 



'Mr. F. V. Theobald, after studying Walker's type of perturbans, writes us that it 

 has toothed claws in the female. 



