COLORATION IN POLISTES. 83 



neath, joints above more or less black, especially those at the apex ; collar more 

 or less black ; prothorax generally more or less margined with pale yellow ; meso- 

 thorax black, with two central, longitudinal, more or less distinct ferruginous 

 lines ; scutellum sometimes divided centrally by a black line; metathorax with 

 a broad, deep, longitudinal groove, finely and transversely striated, ferruginous, 

 generally with three longitudinal Ijlack lines, which are sometimes subobsolete ; 

 sometimes the metathorax is entirely ferruginous, except the groove, which is 

 always black, sometimes entirely black, except a spot on the flanks and a stripe on 

 each side of the groove ; pleura generally yellowish beneath, more or less black 

 laterally. Abdomen of different shades of ferruginous, strongly golden sericeous ; 

 the three basal segments have frequently a more or less distinct, narrow yellow 

 apical margin ; the base of the second, third, and fourth segments is more or less 

 broadly black, sometimes obsoletely so, sometimes only the second or third or 

 fourth is so marked ; ventral segments more or less marked with black at the base, 

 the intermediate segments sometimes banded with yellow. Legs ferruginous, the 

 four anterior coxae, femora, and tibiae beneath more or less pale yellowish, all the 

 coxae more or less black above. Wings fuscous, darker along the costa and in the 

 marginal cell ; second and third submarginal with subhyaline streaks. Length 

 18-21 mm. 

 Hab. Texas, Bermuda. 



P. generosus Cress. 



Male. Head subsericeous, face lon.^, dull luteous ; anterior orbits, a band above 

 the antennae filling up the emargination of the eyes, and mandibles yellowish 

 white or luteous ; venter and occiput black ; cheeks and a dot on each side be- 

 hind the ocelli ferruginous ; clypeus longer than wide, flat, sparsely and finely 

 punctured, apex angular ; ridge between the antennae subtuberculate above ; an- 

 tennae long, black above, fulvous beneath, scape yellowish beneath, narrowly edged 

 with fulvous above ; prothorax fulvo-ferruginous, black laterally, upper margin 

 narrowly edged with yellowish ; mesothorax black, with two short ferruginous 

 stripes on the anterior middle ; scutellum black, with two ferruginous spots ; post- 

 scutellum ferruginous, narrowly margined with black ; metathorax transversely 

 and rather coarsely wrinkled above, with a broad, shallow groove down the middle, 

 a slender stripe on each side of the groove and a spot on each flank ferruginous ; 

 pleura black ; a ferruginous spot beneath, the tegulae and a luteous subangular 

 mark behind the anterior coxae ; tegulae ferruginous, fuscous at the base. Legs 

 fulvous, yellowish beneath, sericeous ; the four anterior coxae above, posterior 

 pair entirely, and all the femora above, black. Abdomen subsericeous, fulvo- 

 ferruginous, a longitudinal mark on the basal middle oT the first segment ; basal 

 margin of second segment dilated above and suddenly dilated laterally ; the nar- 

 row basal margin of the third and fourth segments black ; apex of the second and 

 following segments stained more or less with fuscous ; apical segment blackish, 

 rugulose ; venter black. Length 22 mm. 



Hab. Texas. 



P. texanus Cress. 



Female. Dull ferruginous, sericeous. Head yellow ; vertex, occiput, and pos- 

 terior margin of the cheeks ferruginous ; clypeus subconvex, sparsely punctured, 

 sometimes tinged with fulvous at the base ; antennae entirely fulvo-ferruginous ; 

 narrow margins of the prothorax, sometimes a band at the base of the scutellum, 

 postscutelluin more or less, two stripes on the disc of the metathorax, a spot or 

 stripe on each side, a spot beneath the tegulae, a spot beneath the posterior wing, 



