74 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 52. 



carina of intermediate femora and genital stipes similar to those of 

 capnoptera. 



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

 below, broad anterior orbits not reaching vertex, narrow posterior 

 orbits, posterior border of pronotum including tubercles, lateral lines 

 on scutum not reaching anterior margin, tegulae, spot on base of 

 anterior wings, one large and two smaller spots on mesopleurae, 

 rounded lateral spots on scutellum, transverse fascia on metanotum, 

 four spots (a suppressed curved line) on dorsum of median segment, 

 lateral angles of same, broad fasciae on tergites 1-5, interrupted 

 medially, first greatly and second slightly narrowed medially, small 

 lateral spots on ultimate tergite, triangular lateral spots on sternites 

 2-5 connected by narrow apical lines, spot on anterior coxae below, 

 pale creamy yellow. Coxae (except anterior pair) and trochanters 

 entirely black; femora with more or less of the distal part yellow; 

 tibiae yellow with very dark spot below on first and second pairs; 

 tarsi tawny yellow. Wings somewhat infumated, slightly darker 

 than those of the male but not so dark as those of ventralis. The 

 ultimate tergite lacks lateral ridges and a pygidial area. 



Length. — 15 mm. 



A female from Texas has the mandibles and labrum black with 

 faint pale yellowish markings basally; another, from Arizona, has a 

 pair of discal spots on the scutum, small lateral spots on prothorax 

 and a very large spot on mesopleurae. A male from Arizona has the 

 labrum ferruginous, the yellow on the clypeus restricted to two 

 lateral apical spots, a pair of small lateral spots on the dorsum of the 

 median segment, and the black on the femora much reduced in 

 extent and intensity. 



The male of this species is very similar to the male of capnoptera 

 Handlirsch with which it agrees with respect to the character of the 

 intermediate femora and the development of the antennae. It differs 

 from that species only in the color of its maculations and to a slight 

 degree in the form of the genital stipes. The female, however, is 

 quite closely allied to parata and ventralis, from which it may be 

 distinguished only by the character and color of its maculations. It 

 differs markedly from capnoptera in the absence of lateral ridges and 

 a pygidial area. The association of a male and female of such diver- 

 gent relationships as sexes of the same species without biological 

 evidence to sustain it is open to question. I have retained them, 

 however, as sexes of the same species since they have been so asso- 

 ciated and since I have no data to show that such association is not 

 the correct one. 



Habitat. — New Mexico, Arizona, Texas. 



Number of specimens examined. — Males, 4; females, 3. 



