388 C. R. OSTEN SACKEN'S PRODROME 



lirown, except tlie rinnl angle, wlileh is grayish, tlie hyaline tiiangle near the apex, anil some hyaline spots in 

 the tilth ])osterior cell. 

 Lengtli, 7-8 mm. 



Female. Fiice, including- the callosities, ycllowisli-ferrnginoiis ; front Leset Avitli 3'ellow- 

 ish-gray pollen, frontal callositj' blacl^ ; antenna^ : liasal two joints reddish, the third black, 

 reddish at base ; palpi brownish-red. Thorax blackish, with the nsual broad grayish me- 

 dian stripe, divided by a longitndinal black line ; lateral stripes (between the scntelhim and 

 the humeri) yehow ; a Ijrown stripe separates the thoracic dorsum from the [ileura-^ ; the 

 latter with two }ellow stripes, separated Ijy a dark one. Scntellum reddish, with a blackish 

 spot at the l^ase. which, in some cases, extends as a stripe to the apex, leaving onl}^ a yel- 

 low spot on each side of the scutellum. Abdomen yellow, with four longitudinal black 

 stripes of very varialjle breadth ; in some specimens the intermediate pair of stripes con- 

 sists of a series of disconnected blackish sjiots on segments 2-5. the lateral pair being obso- 

 lete ; in other specimens the stripes are continous and liroader, the lateral pair beginning 

 sometimes on the second, sometimes only on the third, segment; (the picture of the abdo- 

 men is very like that of C. viffahis); the two or three last segments are usually blackish; 

 venter yellow anteriorly, Ijlackish posteriorly. Legs reddish, latter half of front tibite and 

 front tarsi, black ; tips of the other tarsi and, in some specimens, a considei-able portion of 

 the hind femora, l)lack. Wings jjrown ; second basal, anal, and fifth posterior cells, anal 

 angle and a triangle on the hind margin, within the second and third posterior cells, hy- 

 aline ; a brown clond on the last section of the fifth vein. 



Male. Face yellow, lateral callosities and cheeks black, shining; facial orbits and the 

 stripe separating the cheeks from the callosities, are covered with a pale fulvous pollen ; 

 palpi black ; antennae black, first joint once and a half as long as the second. Thorax 

 Ijlack, with black hairs ; on each side of the dorsum, above the root of the wings, between 

 the humeri and the scutellum, there is a distinct stripe of pollen, with an almost metallic 

 greenish lustre, appearing yellowish in a difierent light; the nsual median stripe on the dor- 

 sum shows a similar metallic greenish lustre, but darker and without yellow admixture ; (it 

 is almost invisible, unless the light falls oljliqueh' from the side of the abdomen and is 

 easily lost in worn specimens); a shade of the same pollen is visil^le on the scutellum; pleu- 

 rae with alternately brown and greenish-poUinose stripes. Abdomen brownish black, the 

 lateral edge of the second, often also of the first and third segments, brownish-yellow ; 

 along the middle of the dorsum, especially on segments 3, 4, 5, a faint longitudinal stri^ie of 

 grayisli pollen is visible. Front legs blackish, except the base of the tibia3 which is brown- 

 isli ; middle pair brownish, except the proximal half of femora and tip of tarsi, which are 

 black ; hind pair brownish, femora and end of tarsi black. Wings altogether blackish, ex- 

 cept the anal angle, which is grayish; a small hyaline triangle occupies the distal half of 

 the second and third posterior colls ; small subhyaline dots are visiljle on the fourth longi- 

 tudinal vein; before tlie discal cell and at the proximal end of the fifth posterior cell ; a 

 faint subhyaline streak runs across these two dots and the fifth posterior cell to the posterior 

 margin. 



Hah. I have two females from Dist. Columbia and Georgia (J. Eidings) ; males from 

 Kentucky (F. G. Sanborn), Missouri (C. V. Ptiley), and a third specimen without indication 

 of locality. 



