S . Head transverse, compressed, sometimes orbicular or sub- 

 triangular ; eyes generally more or less emarginate ou the inside, 

 in some species ovate or round ; ocelli three, placed in a triangle 

 on the vertex ; mandibles arcuate, generally tridentate at apex ; 

 thorax short, massive ; tegul* usually large, sometimes remarkably 

 so. Wings broad and ample, the fore wing with three, in some 

 species only two, cubital cells ; the 2nd and 3rd each receive a 

 recurrent nervure ; when only two cubital cells are present, the 

 2ud recurrent nervure is obsolete. Legs long and pubescent. 

 Abdomen ovate, generally strongly curved downwards towards 

 apex, the apex armed Avitli blunt teeth or spines; the 1st segment 

 sometimes petiolate. 



Keij to the Species. 



Females*. 

 A. Head black ; thorax red. 



a. Second abdominal segment with two spots, 

 the spots lateral. 

 a'. The spots of yellow or f^olden pubes- 

 cence. 

 (r. Apical margin of 2nd abdominal seg- 

 ment with a transverse fascia of 

 yellow or golden pubescence. 

 a^. First abdominal segment black, 

 with a semilunar spot of yellow 



pubescence M. maximincp, p. 10. 



h\ First abdominal segment entirely 

 black. 

 «'. Anal segment rufo-ferruginous. 

 «\ Lateral spots on 2nd abdomi- 

 nal segment small ; marginal 



fascia very narrow M. pulchrinella, p. 10. 



b". Lateral spots on 2nd abdomi- 

 nal segment large ; marginal 



fascia broad M. tiitinii, p. 11. 



6". Anal segment black. 



a^. Transverse band ou 2nd and 3rd 

 segments broadly interrupted 



in the middle M.fece, p. 11. 



6\ Transverse band on 2nd and Srd 



segments entire M. lilliputiana, p. 11. 



h^. Apical margin of 2nd abdominal seg- 

 ment without a transverse fascia. 

 «■'. Fourth abdominal segment with a 

 transverse fascia of yellow or golden 

 pubescence, 

 rt'. Head with golden pubescence .. M. pulchricfps, 'p. 12. 

 I)\ Plead without golden pubescence. 

 r/\ Thorax posteriorly armed with 



two teeth M. tridum/iduta, p. 11, 



}>''. Thorax not so armed . . ..... M. soror, p. 12. 



//■'. Fourth abdominal segment without [p. 12. 



a transverse fascia M. pectino-spinata, 



* In many species only one sex is known. 



B 2 



