300 BULLETIN 45, UNITED STATES NATIONAL MUSEUM. 



AnteiiiiiP lO-jointod, the scape siibdavatc slightly curved at base, 

 in botli sexes tenninatiiig in a S-Jointed eliib, the funiclar joints vary 

 but the tirst in both Kexos i.s usually minute, the second uiul third sub- 

 e(|ual, cylindiic, in 9 , while in the <? the sc<'ond is enlarged, swollen, 

 the third S(;arccly half aslarj;e, thinner andobli(|uely truncate at apex. 



Thorax subovoid, convex, the niesonotuni ran'ly li times as long as 

 .vide, with or without furrows; scutelluin transversely elevated, convex 

 or cushion shap<'d, separated from the mesonotum by a transverse 

 de|»ression or furrow; metathorax short, the metapleura bounded above 

 by a carina. 



Wings veinless. 



Abdomen, in 9, pointed-ovsite, depressed, 0-jointed, the first joint 

 petioliforni, striated, the secoiul longer than the following together, 

 sm(K)th, with 2 oblong foveohe at base, in $ oblong oval, 7- or 8- jointed. 



Legs <'lavate, the basal joint of hin«l tarsi about thrice as long as the 

 second. 



Distinguished from Platygnster by the shorter, rarely distinctly 

 gro<»ved mesonotum, broader head, ditferent antenna^, and the higher, 

 nuu'e c<mvex, or eushioned-shaped scutelluin, which has a deep trans- 

 verse impression all across the base. 



TABI.E OF SPECIES. 



FEMALES. 



Mesonotiil furrows entire 6 



Mt'aonot.'il furrows iiidifivtcd only posteriorly 3 



Mesonotum without trace of furrows, or the faintest trace of them posteriorly. 

 Vertex not transversely aciculated 2 



Vertex transversely acicnlatefl. 

 Coxa; black. 



Legs Mack or brown-hlack. 

 Antenna' black; jieilicel as long as the two following joints united and 

 much thicker, the tip pale; first joint of fuuicle small, second and 

 . third larger, nearly equ.al, the second slightly the larger, fourth 



; transverse; club joints, except the last, as broad as long. 



P. 8ALICICOLA 



Antenna' brown-black ; pedicel much longer tlian the two following 

 joints united and much stouter; joints one and two of funiele very 

 ' small, ni'arly eciual. the third slightly larger, fourth transverse; 



:■- club joints, except the last, only slightl." longer than thick. 



- ' P. DIPLOSIDIS 



Coxa> dark rufous or piccons. 



Legs rufous, the tarsi yellowish, femora .and tiba> often dusky. 

 Scape black, sometimes pale at base and apex, flagellum dark brown; 

 pedicel as long as the two IVdlowing joints united and stouter; 

 joints one and three of funiele minute, the second slightly larger, 

 fourth longer than wide; club joints except the last, very slightly^ 

 wider than long P. UACCHARicoiJk. Ashm. 



Front legs, all trochanters and tarsi honey-yellow, sometimes the front 

 femora and tibiie dnsky, middle and posterior femora and tibiae dark 

 brown or black ; sometimes all tbe legs pale brown. 



