6 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. CI. 



mesoscutum and with or without carinae parallel to its hind margin. 

 In cayennensis the pronotiim has no carina (text fig. la), in affinis 

 there is one distinct carina (text fig. 15), and in guzeratensis (text 

 fig, Ic) there are two well-marked carinae. The hind margin of the 

 scutellum is always entire, the metanotum either broadly rounded be- 

 hind as in a^finis (text fig. '2g and h) or projecting and 2-toothed as in 

 gigas (text fig. 2e and /), the propodeum is sometimes equal in length 

 to the metanotum as in affinis or may be twice as long as the metano- 

 tum as in the case of metaUica (text fig. 2a and h). The front leg 



Fig 2. — Diagrams of scutellum, metanotum, and propodeum of Leucospis, viewkl 

 from above and in profile. c and l)=l. metallica ; c and d=l. robertsoni ; e and 



f=GIGAS ; g AND ft.=AFFINIS. 



bears the usual curved forked spine near the ap)ex of tibia beneath, and 

 the usual comb on its metatarsus, the middle tibia bears a slender 

 straight spine on its under side near apex, while the hind tibia bears 

 two spines at apex beneath, one of which is stouter than the other (pi. 

 4, fig. 23). The hind coxae and femora are much larger than those 

 of the front and middle legs, the hind coxa sometimes has its dorsal 

 margin broadly rounded and entire as in cayennensis^ or may have a 

 distinct tooth as shown in affinis (pi. 4, fig. 24) . The femoral teeth are 

 quite variable both in size and number; in opalescens, for example, 

 the basal tooth is large and followed by eleven smaller, regular 

 teeth (pi. 2, fig. 9) while in affinis the large basal tooth is followed 



