6 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.60. 



Specimens examined are two male paratypes, Austin, Texas, De- 

 cember 13, 1899, A. L. Melander (Aldricli). On comparison with 

 original description it would appear that these specimens have faded ; 

 that description alluding to jet-black general color and black halteres. 



I have not described the genitalia of the species of this genus, as 

 it is not necessary at present to base the classification upon them. 



BIBIODES HALTERAUS CoQnillett. 



Bibiodes Jialteralis Coquillett (D. W.), New North American DIptera, 

 Proc. Ent. Soc. Wash., vol. 6, No. 3, July, 1904, p. 171 [California]. 



Male. — Black, shining, legs dark reddish brown ; halteres yellow ; 

 head with short, body and legs with rather long yellowish white 

 hairs; spurs of front tibiae rufous, the outer long and stout, the 

 inner a mere pointed tubercle; wings nearly hyaline; the anterior 

 veins and stigma brown, the posterior nearly colorless. Length of 

 wing, 3.5 mm. 



Specimens examined are from San Mateo County, California, 

 C. F. Baker (type) ; Los Angeles, California, Coquillett (U.S.N.M.) ; 

 Claremont, California, Baker (Aldrich). 



Genus BIBIO GeoflFroy. 



A considerable number of the older names applied to American 

 species of this genus remain unidentified. This is chiefly due to 

 the fact that characters used in later diagnoses are not mentioned 

 in earlier ones, and that elucidation of the obscure points has not 

 been possible on account of lack of types or of opportunity of 

 examining those in existence. 



The male genitalia of Bibio undissected have not been found 

 available for taxonomic use. They are not heavily chitinized, hence 

 are not all constant in appearance in dried specimens of the same 

 species; the superior plate is decidedly emarginate in all species 

 examined, but the width of the emargination varies greatly, being 

 strictly correlated with the degree to which the forceps are spread. 

 Dissection of excised genitalia has not been attempted. 



KEY TO THE) SPECIES : MALES. 



A. Inner spur of front tibia long, sometimes nearly as long as outer. 



B. Legs almost entirely black criorMnus. 



BB. Legs with at least one joint yellow to rufous. 



C. Only the femora rufous femoratus. 



CC. More of legs yellow to rufous. 



D. Smaller species (wing, 4.5-6.5 mm.) ; body with rather short pale hair. 

 E. Hind metatarsus distinctly shorter than succeeding three joints 



together abbreviatus. 



EE. Hind metatarsus about as long as succeeding three joints together. 



fraternus. 



DD. Larger species (wing, 7.5-9.5 mm.) ; body with copious long gray to 



black hair variabilis. 



