434 PROCEEDINGS OF THE ACADEMY OF [1899. 



18. Clypeus punctured like front; dorsulum with a slender, raised 



line anteriorly in middle ; sides of clypeus yellov/ 



rxujosieejis 9. 

 Clypeus with deep, separated punctures, front rugoso-punctate; 

 clypeus not yellow, except anterior margin in d^. 



proximus 9 c?. 



19. Head and thorax above without yellowish-brown hair . 20 

 Head and thorax above with dense yellowish-brown hair; 



petiole smooth, shining peculiaris 9. 



20. Head and thorax black 21 



Head and thorax rufous coloralus 9d*. 



21. Apical abdominal segments yellow; tibiae black, the medial 



pair striped with yellow shnillimus 9 . 



Apical abdominal segments narrowly margined with yellow; 

 tibiae more or less reddish 22 



22. Wings blue-black. Length 18-21 mm. . . pundatus 9(^. 

 Wings subhyaline, costal margin fuscous. Length 14 mm. 



emarginatm S'. 



Labus brasiliensis n. sp. 



Head black, clypeus except medially, transverse spot behind the 

 antennae, the eye emarginations, mandibles except apex, scape 

 except a line above, broad stripe on cheeks, a large spot beginning 

 at summit of eyes and extending toward middle of occiput, bright 

 yellow; thorax black, pronotum entirely, tAvo lines on dorsulum, 

 two spots on scutellum, and postscutellum, teguke, large spot beneath 

 wings, middle segment except sides and in medial sulcus, all the 

 coxae and trochanters more or less, the four anterior femora except 

 hasally, the hind pair except a stripe above, all the tibiae and 

 tarsi, except a stripe on hind tibiae, bright yellow; petiole except 

 a medial and lateral stripe, second segment beneath excej)t two 

 spots beyond middle laterally, and above except base and greater 

 part of disc, and the remaining segments more or less, bright 

 yellow; in the male the black spots of second ventral segment are 

 spread out so as to cover most of the segment; flagellum rufous 

 beneath, black above; wings pale fulvo-hyaline, stigma yellowish. 



9. — Head with strong, separated punctures, those on cheeks 

 finer; clypeus rather small, almost as long as broad, the fore 

 margin tridenlate, the medial tooth indistinct; a strong carina 



