125 



IIoAvever, befoi-c we transfer en masse the heterogeneous 

 species described nnder Prosopis to Hylaeus it will be well 

 to segregate some of the species into proper genera. 



The following table will serve to distinguish some genera, 

 described species of most of which have been placed in Prosopis. 

 This work of segregation is far from complete. Certainly most 

 of the Australian species described as Prosopis Avill not fall 

 in any properly defined genus Hylaeus. l^either material at 

 hand nor time permits an investigation of all the genera which 

 should fall into the Tlylaeidae. 



TABLE OF SOME GENERA OF HYLAEIDAE. 



1. Mandibles flattened at apex or tridentate or bidentate 



in both sexes 2 



Mandibles acute at apex, edentate, elongate, nearly straight. 

 })ropodeum rugose, angnlate at the sides and subcarinate, the 

 triangular basal area well defined with its sculpture different 

 from the rest of the propodeum, first recurrent nervure received 

 by the first culutal cell or interstitial, the second interstitial 

 with the second transverse cubitus or received beyond it, supra- 

 clypeal area short, bounded by lateral cariuae. Face broad, 

 usually broader than long, clypeus trapezoidal, about as high 

 as broad at its anterior margin, labrum triangiilar, 



$ Stipes greatly produced apically into a slender process 

 nearly as far beyond the apices of the sagittae as their 

 length, eighth sternite with a short rounded median process. 



Coloration. Thorax black, frequently with yellow and fer- 

 ruginous markings, legs and first segment of the abdomen 

 usually more or less ferruginous N othylaeus n. gen. 



2. Mandibles bidentate at apex 4 



^fandibles tridentate at apex 



certain Australian "Prosopis" 



Mandibles flattened at apex, not toothed o 



3. Mandibles not channelled, truncate at the apex, supra- 



clypeal area not angnlate between the bases of the 



