284 U. S. NATIONAL MUSEUM BULLETIN 216 



Black. Palpi of male white, of female whitish to fuscous; scape 

 sometimes marked with white in front; flagellum dark reddish brown 

 below, the first one or two segments of the male flagellum often 

 stramineous below; usually more or less of hind corner of pronotum 

 white; tegula white, its apex usually brownish; front coxa and tro- 

 chanters of male white, the coxa more or less fuscous basally; front 

 femur, tibia, and tarsus of male fulvous, the femur and tibia pale 

 fulvous or yellowish in front; front leg of female fulvous, its coxa partly 

 or entirely fuscous; middle coxa and trochanters of male white, the 

 coxa more or less fulvous and/or fuscous basally; middle coxa and 

 trochanters of female fulvous, the coxa often more or less fuscous 

 except at apex; middle femur fulvous; middle tibia fulvous, with a 

 premedian whitish band, basad of which and a little apicad of which 

 the tibia is more or less infuscate; middle tarsus fulvous to fuscous 

 brown, the segments whitish basally; hind coxa, trochanters, and 

 femur fulvous, the coxa often more or less blackish ; hind tibia black- 

 ish, with a broad white submedian band; hind tarsus fuscous, the 

 first three segments white basally and the fifth segment with a variable 

 amount of white basally; hind margin of tergites dark brown to 

 stramineous. 



In specimens from many localities the hind corner of the pronotum 

 is narrowly white and the last segment of the hind tarsus is white at 

 the base below, but not above. In specimens from other localities the 

 hind corner of the pronotum may lack the white and the last segment 

 of the hind tarsus have a complete basal white ring. In those from 

 still other localities there may be other combinations or intermediate 

 conditions in these color characters. We have not been able to use 

 these differences for distinguishing definite subspecies, so leave them 

 with this brief discussion, at the same time realizing that they are of 

 value for distinguishing populations. 



This species is very close to the widespread and common Palaearctic 

 Itoplectis altemans Gravenhorst, 1829. Possibly it should be con- 

 sidered a subspecies of /. altemans, but it is treated as a distinct 

 species because the close similarity of many species of Itoplectis tends 

 to make decisions on specific limits and relations very difficult in this 

 area, and suggests caution in changing the traditional classification. 

 /. guadricingulata differs from /. altemans in having the subapical 

 flagellar segments a little longer and more slender, the hair on the 

 mesoscutum averaging a little sparser, the tooth on the front tarsal 

 claws of the female a little more acute, and the flagellum blackish 

 brown beneath except toward the base. In I. altemans the flagellum 

 beneath is entirely pale yellow to yellowish brown. 



Specimens (514 cf, 5459): From Alaska (Big Delta, Fort Wrangle, 

 Hollis, Ketchikan, Kodiak, Juneau, Mount McKinley at 1,600, 1,700, 



