SPH.EH0PH0K1A. 



21 



3. Legs entirely or iu great part yellow picticauda, Bigot. 



Legs for the most part black micrura, O. Sacken. 



4. Bands of the abdomen broad and nearly straight Sp. 



Bands of the abdornen narrower, bilaterally oblique on their 



posterior rnargins Spp. (nos. 5 & 6). 



1. Sphaerophoria picticauda. * " 



Sphcerophoria picticauda, Bigot, Ann. Soc. Ent. Fr. 1884, p. 102 l . 



BoJb. Mexico K Omilteme 8000 feet, Sierra de las Aguas Escondidas 9500 feet, and 

 Acaguizotla 3500 feet, all in Guerrero, Teapa in Tabasco (H. H. Smith). 



Bigot's vague description would leave one very much in doubt, save for the pecu- 

 liarly marked fifth abdominal segment, which he recognizably describes. As the 

 species seems to be very variable, I give here a full description, based upon about 

 twenty-five specimens : — 



Male. Face in profile more prominent than in S. cyKndrica, with a greater coneavity on the upper part. Pace 

 yellow, with a median blaek stripe, which is often almost wholly obsoletc, leaving only a brownish streak, 

 or a small spot on the tubercle. Prontal triangle with a shield-sbaped black spot, sometimes leaving 

 only a narrow orbital yellow margin, at other times small. Antennae black with the third joint yellow 

 below, sometimes rcd with the third joint black above. Mesonotum dark green or greenish-black, some- 

 times distinctly bronzo-coloured, but little shining : the yellow lateral stripe truncate at the suture ; a 

 small yellow spot on the postalar callosities. Pleurse shining blue-black, with two or three yellow or 

 yellowish spots. Scutellum yellow, or reddish-yellow, sometimes with a darker cloud across the disc. 

 Abdomen opaque black ; first segment, except the lateral yellow spots, shining, somewhat metallic, black ; 

 secoud, fourth, and fifth segments narrowly in front and behind, and the sixth in great part, shining 

 black ; second segment with a yellow transverse band, wider at the sides, sometimes dissolved in two 

 triangles ; third and f ourth segments each with a gently arcuate band j fifth segment with two median 

 streaks or comma-like spots, and two larger lateral ones. Hypopygium small, black. Legs often yellow, 

 with the hind legs chiefly, and all the tarsi, brownish ; usually the four anterior legs are in great part 

 brownish, and the hind pair is darker ; coxae chiefiy brownish or black. Wings sometimes nearly 

 hyaline ; usually very distinctly tinged with brownish. 



Female. Front shining black, with the orbits on the lower two-thirds yellow. Legs usually lighter-coloured, 

 light yellow, exeept the hind tarsi ; coxa3 yellow. 



Length 7-9 millim. 



2. Sphserophoria micrura. 



Sphcerophoria micrura, Osten Sacken, Western Diptera, iu Bull. U.S. Geol. & Geogr. Survey, iii. 

 p. 330 x j Willist. Synopsis N.-Am. Syrphidse, p. 107 2 . 

 Hab. United States, California 1 2 . — Mexico, Omilteme in Guerrero 8000 feet 

 (H. H. Smith). 



A single male specimen from Omilteme, agreeing well with the descriptions. The 

 black facial stripe reaches quite to the antennae, and the second and third abdominal 

 bands are gently arcuate. The postalar callosities have no yellow spot ; there is no 

 yellow on the pleurse ; and the legs are darker than in S. picticauda. Bigot. The two 

 species are suspiciously alike. 



