88 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 52. 



which may appear as anterior emarginations, third, fourth, and fifth 

 more or less distinctly biemarginate on anterior border, second, 

 third, and fourth acutely notched at middle of posterior border, 

 lateral spots on sternites 2-5, those on second sometimes connected 

 by an apical line, femora except to a slight extent basally, tibiae, and 

 tarsi, yellow. 



Length. — 17-20 mm. 



The wings of the female are conspicuously clouded medially; 

 those of the male are hyaline with only a trace of the clouding on the 

 wings of some individuals. The veins are dark brown. The flagel- 

 lum on the female is usually fulvous or tawny below, but on the male 

 the color is limited to the more basal segments. The pubescence is 

 light, sparse and relatively short. The variation in the maculations 

 of this species is greater than usual, especially on the female. The 

 great majority of the females do not show discal marks on the scutum 

 but a few specimens show not only a well developed pair of longi- 

 tudinal discal lines but also a posterior transverse line. On some the 

 sides of the thorax and median segment are almost wholly yellow, 

 whereas on others these parts are almost entirely black. 



Habitat. — Tennessee, Iowa, Illinois, Kansas, Texas, New Mexico, 

 Colorado, and Arizona. 



Number of specimens examined — Males, 31 ; females, 46. 



BEMBIX AMOENA Handlirsch. 



Figs. 148, 149, 189, 210. 



Bembex amoena Handlirsch, Sitz. Akad. Wissensch. Wien, Math. -Nat. CI., 

 vol. 102, 1893, p. 769, male, female, pi. 1, fig. 32; pi. 6, fig. 31. 



Male. — Black: Labrum, mandibles except apices, clypeus, lower 

 part of frons, scape below, broad anterior orbits sometimes shortened 

 above, narrow posterior orbits broader below and not reaching vertex 

 above, spot on sides of prothorax sometimes including tubercles, 

 spot on tegulae, wanting in some specimens, large irregular spot on 

 side of mesopleurae united on mesosternum, pair of small spots on 

 mesosternum in front of middle coxae, sometimes wanting, fasciae on 

 tergites entirely absent or present on 1-5, first broad laterally, narrow 

 and widely interrupted medially, remainder narrow, strongly undu- 

 late and narrowly interrupted medially, pair of median spots on 

 sixth, lateral spots on sternites 1-5, sometimes reduced to 2-3, 

 coxae below more or less, trochanters more or less in some specimens 

 and in others not at all, femora below, tibiae except spot below in 

 some specimens, and tarsi, greenish yellow or white. 



Segments 5-8 of the flagellum when viewed from above show small 

 but distinct spines on the posterior surface, and segments 5-12 bear 

 pits or excavations on their posterior surfaces best developed on 



