POLYBIA. 



383 



tibije with two spines at apex, tlie claws simple. Wings long ; fore 

 wino- with the radial cell both broad and long, the apex sharply- 

 acute and reaching very nearly to the apex of the wing ; the 

 cubital nervure continued to the margin of the wing, hence four 

 cubital cells — the 1st very large, about equal to the 3rd and 4th 

 united ; the 2nd very small, constricted towards the radial cell, 

 receivin"' both recurrent nervures ; the 3rd cubital cell a little 

 lar<^er than the 2nd and a little wider at apex than at base ; the 

 4th a httle smaller than the 1st. Abdomen petiolate, the petiole 

 cylindrical at base, swollen and spherical at apex above ; 2ad 

 seo-ment generally shortly petiolate at base, increasing in width to 

 the apex ; remaining segments gradually smaller, closing into the 

 2nd telescopically. 



It is difficult to distinguish the insects belonging to this genus 

 from those coming under the genus Icaria. So far, however, as 

 the Indian species are concerned, they are slighter, more slenderly 

 built than any of the Icurice. 



Key to the Species. 



a. Mesonotum with two distinct parallel longi- 



tudinal stripes. 

 a'. Of comparatively large size. ^ , length 



11-12 mm P- orientalis, p. 383. 



b'. Of comparatively small size. §, length 



7 nim -P. stigma, p. 384. 



b. Mesonotum without marks, or markings 



indistinct. 

 a', 2nd and 3rd abdominal segments with 



large lateral yellow spots ; remaining 



seo-inents immaculate P. indica, p. 384. 



b'. 2nd to 5th abdominal segments with 



transverse narrow yellow bands above. . P. sumatrensts, p. 385. 



609. Polybia orientalis, Smiss. Mon. Guep. Soe. p. 208, f? , pi. xxvi, 



fig. 2 ; S7}iith, Cat. v, p. 133. 



5 . Closely allied to P. indica, and resembling it greatly, but 

 lighter in colour and with the yellow markings 

 )t.-=^^ brighter and more profuse ; P. orientalis is 



also constantly smaller. Light rufescent 

 brown ; the mandibles, the clypeus except a 

 reddish-brown cloud in the middle, the space 

 between the base of the antenna?, the sinus of 

 the eyes and the inner and outer orbits broadly, 

 a spot in front of the anterior ocellus, the 

 scape and flagellum of the antennae in front, 

 the apical joints of the latter above, the pro- 

 thorax except for a transverse streak in front 

 Fie WQ.—rolyhia ^"^ another on each side, two medial longi- 



orientalis,2- i- tudinal parallel lines on the mesonotum, the 



scutellum, postscutellum, sides of the thorax, 



and median segment except in the sutures, two broad vertical 



