234 M. W. R. de V. GRAHAM 



Antenna with length of flagellum, not counting the pedicellus, slightly to 

 (usually) distinctly greater than breadth of head ; sixth funicular segment 

 most often longer than broad. Gastral petiole often with a sharp trans- 

 verse crest, which forms the front edge of its main sculptured portion . . 4 



2 (1) Gaster much shorter than thorax, 1 to 1-5 times as long as broad, obtuse 



apically ; basal tergite occupying half or slightly more than half the total 

 length. Propodeum with spiracular sulci distinctly impressed, reaching as 

 far as the supracoxal flanges. Antenna with third segment of clava very 

 small, its length at most about one fifth that of the whole clava. Mandi- 

 bular formula 3.4 . . . . picinervis Thomson (p. 240) 



- Gaster not or only slightly shorter than the thorax, 1-5 to 2-15 times as long as 



broad, pointed apically ; basal tergite occupying at least slightly less than 

 half the total length. Propodeum with spiracular sulci shallow and poorly- 

 defined. Antenna with third segment of clava occupying fully one quarter 

 of the total length .......... 3 



3 (2) Both mandibles with four teeth. Propodeum with median carina often irregu- 



lar or incomplete, sometimes straight and sharp ; panels of median area 

 most often with some fine carinulae or rugosities as well as the reticulation 



brevicornis Thomson (p. 240) 

 Left mandible with three teeth, right mandible with four. Propodeum with 

 median carina complete, straight and sharp ; panels of median area rela- 

 tively uniformly reticulate, without or with few rugosities 



simillimus Delucchi (p. 241) 



4 (1) Antenna with length of flagellum, not counting the pedicellus, only very 



slightly (1.05 times) greater than breadth of head ; sixth funicular segment 

 quadrate or at most 1-2 times as long as broad, not or hardly longer than 

 first segment of clava ; clava 2 to 2-5 times as long as broad, all its seg- 

 ments closely compacted, the third segment occupying one fifth or less of 

 the total length of the clava. Gastral petiole without a distinct anterior 

 transverse crest, its main portion transversely aciculate 



picinervis Thomson (p. 240) 

 Antenna with length of flagellum, not counting the pedicellus, 1-2 to 1-4 

 times the breadth of the head ; sixth funicular segment 1 • j to 1 -8 times as 

 long as broad, often distinctly longer than the first segment of the clava ; 

 clava 3 to 3-5 times as long as broad, with a deep suture between at least its 

 first and second segments, the third segment occupying one quarter to one 

 third of the total length of the clava. Gastral petiole often with a distinct 

 anterior transverse crest ......... 5 



5 (4) Malar space fully one-third the length of an eye. Legs extensively testaceous 



as in crassipes (q.v.), but femora less stout. Sculptured part of gastral 

 petiole about twice as broad as long ...... sp. indet. 



Either {crassipes) malar space about one quarter the length of an eye or 

 slightly more, sculptured part of petiole at most 1-5 times as broad as long, 

 and femora very stout ; or legs relatively darker ..... 6 



6 (5) Mid femora pale, or with at most a small dark streak beneath ; fore femora 



pale, or with at most their proximal third dark ; femora stout, especially 

 the hind ones, which are, excluding the trochantellus, only 3-2 to 3-5 times 

 as long as broad. Sculptured part of gastral petiole varying from 

 quadrate to 1 -5 times as broad as long . . . crassipes Thomson (p. 238) 



- Mid femora with at least a bold dark streak beneath ; fore femora with at 



least rather more than their proximal half dark ; hind femora less stout, 

 excluding the trochantellus 3 -7 to 5 times as long as broad. Sculptured part 

 of petiole varying from quadrate to three times as broad as long . . 7 



