N0.21T3. A REVISION OF THE BEMBICINE WASPS— PARKER. 91 



femora except broad stripe above on all and a short one below on 

 posterior pair, tibiae except narrow line below on anterior and middle 

 pairs, and tarsi, yellow or yellowish white. The markings of the 

 abdomen are decidedly white. 



Between these two extremes I have before me a very complete 

 series of gradations wherein the extensive markings of the one are 

 almost imperceptibly reduced to the meager maculations of the 

 other. In other respects the series is remarkably uniform. The 

 scape is broad and stout and viewed from the side is larger apically 

 than at the base. Segments 5-8 of the flagellum are spinose posteri- 

 orly and 4-12 bear pits or excavations on their posterior surface, 

 most conspicuous on 9-11. The apical segment seen from above is 

 curved and widest at the base, the width decreasmg perceptibly 

 toward the apex. The middle femora are dentate below and the 

 middle tibiae bear a longitudinal carina on the inner side. The spur 

 at the apex of the middle tibia is less than half the length of the 

 middle metatarsus. The second sternite bears a prominent, laterally 

 compressed, median process, and the sixth a process equally promi- 

 nent, usually bifurcate at the apex, its ventral surface flattened or 

 provided with a median groove but not placed parallel with the 

 long axis of the body as in the case of amoena. 



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

 part of frons, spot before anterior ocellus, broad anterior orbits, poste- 

 rior orbits broad below, prothorax except dusky spot in front of 

 tubercles and an anterior dorsal median spot sometimes broken into 

 lateral spots, tegidae, lateral lines on scutum, pair of longitudinal 

 discal Hues and a posterior transverse discal line, sometimes wanting, 

 on scutum, transverse fascia on posterior border of scutellum en- 

 larged laterally, fascia on metanotum rai:ely wanting, curved fascia 

 on doi-sum of median segment, its lateral angles and sides except a 

 median black emargination on dorsal border of side, metapleurae, 

 mesopleurae whoUy or for the most part, broad fasciae on tergites, 

 all continuous except the first, which is nan-owly interrupted medi- 

 ally, the second or second and third inclosing a pair of dorsal elliptical 

 black spots, which in some specimens are united with the anterior 

 black border in the form of emarginations, fourth and fifth with a pair 

 of anterior dorsal emarginations and a less evident pair of lateral 

 ones, second to fifth with a deep acute median notch on posterior 

 border, spot on apex of ultimate tergite, reduced in some specimens 

 and wanting in others, lateral spots on sternites 1-5 or 2-4, legs 

 almost entirely in the lighter specimens, in the darker ones spots on 

 anterior and middle coxae, femora except above and stripe below on 

 posterior pair, tibiae except stripe below on all, and tarsi, yellow or 

 yellowish white. 



Length. — 17-19 mm. 



