16 G. E. J. NIXON 



13 Tergite 3 as heavily sclerotised as 2, conspicuously dome-shaped, longer than 2 ; the 



two tergites together form a carapace beneath which the more apical segments are 

 completely hidden. 



Areolet large, the 2nd transverse cubitus arising from the 2nd abscissa of the 

 radius ; tergite 2 without a median field. Africa . BULUKA de Saeger (p. 265) 



- Tergite 3 always smooth, polished and never with tergite 2 forming a carapace, except 



in the basimacula-group of Protomicroplitis but this group has the areolet very 

 small with the 2nd transverse cubitus arising from the 1st and tergite 2 with an 

 elongate, median field, bordered on each side by a rugose furrow. Old and New 

 World .... PROTOMICROPLITIS Ashmead (part) (p. 234) 



14 Mesoscutum with very deep, smooth notaulices ; median lobe of the mesoscutum 



raised, shield-like ; 1st abscissa of the discoideus extremely short, only about one 

 third as long as the 2nd. Peru .... PRASMODON gen. n. (p. 205) 



- Mesoscutum without notaulices except that their course may sometimes be indicated 



by a slight coarsening of sculpture or row of foveae (Microgaster spp.) ; median 

 lobe of the mesoscutum never thus raised ; 1st abscissa of the discoideus rarely as 

 short as this ............ 15 



15 Body more or less completely polished, at most with a little fine punctuation towards 



front of mesoscutum. 



Propodeum highly polished, its sculpture consisting at most of a medial keel ; 

 ovipositor very short, almost hidden ........ 16 



- Body not completely polished. 



Stigma never orange-yellow (except in the mediatus-group of Protomicroplitis 

 but this group has the propodeum coarsely rugose) ; vannal lobe with distinct 

 apical notch ............ 17 



16 Tergite 2 with two divergent furrows that set off a very large, triangular area that 



occupies the greater part of the tergite ; vannal lobe not notched at apex and 

 hence not defined as such ; very large species, ca. 7 mm. with orange-yellow stigma. 

 Red-fulvous with dark maculated wings ; 1st abscissa of the discoideus less 

 than half as long as the 2nd. Brazil . . . LARISSIMUS gen. n. (p. 204) 



- Tergite 2 with two convergent furrows that almost meet behind and then curve 



outwards to the lateral margin of the segment, dividing it clearly into three areas of 

 which the median is narrowly triangular and widest in front ; vannal lobe notched 

 at apex ; length ca. 4-5 mm. ; stigma evenly dark brown. 



Brightly coloured species with head and gaster reddish-yellow and thorax mostly 

 black with yellowish propodeum. N. Guinea 



EUTERPE- group of Protomicroplitis (p. 250) 



17 Second abscissa of the mediella of the hind wing about two and a half times longer 



than the 1st ; 1st abscissa of the discoideus of the fore wing distinctly less than 

 half as long as the 2nd ; claws with a close pectination of 6-8 black spines. 

 Bright fulvous species ; propodeum polished with medial keel. N. Guinea 



PARENION gen. n. (p. 208) 



- Second abscissa of the mediella of the hind wing always much shorter in proportion to 



the 1st, about one and a half times longer ; 1st abscissa of the discoideus of the fore 

 wing about as long as the 2nd or even longer (only exceptionally shorter and then 

 the propodeum is not both polished and with medial keel) ; claws without a 

 pectination of fine spines, though spines, sometimes stout enough to be described as 

 teeth, less evenly spaced, are sometimes present in species of Microgaster but all 

 these have a strongly rugose propodeum . . . . . . . 18 



18 Tergite 1 always distinctly widened towards apex, usually distinctly shorter than its 



apical width, rarely slightly longer ; tergite 2 not distinctly shorter than 3 and, 

 with the exception of Microgaster politus, strongly rugose all over and without trace 

 of a median field. 



