Part II.] 
Waterstox ; On Chalcidoidea. 
13 
last 3 funicular joints and club blackish. The rest more or less rufous. 
Wings brown tinted, darker round the stigma. Femora and tibiae 
blackish, knees and tarsi more rufous. Inside of femora obscurely paler. 
The setigerous tergite which forms rather more than the basal half of 
the ovipositor, rufous. Pile everywhere whitish. 
Easily told by the face and by the long ovipositor which is nearly 
half as long again (17:12) as the abdomen. 
Head. Pronotum with coarser punctuation than in T. ruficaudis 
Cam., and definitely umbilicated on the frons. The intertorular area 
triangular (i.e., the toruli rather wide apart) and reaching superiorly to 
about ^ from the top of the scapal furrow. Below the toruli and above 
the clypeal edge are two hollows between which the surface is dull. In 
ruficaudis the intertorular area is short with subparallei sides, its upper 
knife-like edge thinning out before |. The toruli are approximated 
with no hollows below and between them, and the clypeus is a narrow 
shining median line. Mouth parts ; labruni quadrate with rounded 
distal angles, yellowish, thin and clear, with 18-20 fringing bristles 
Mandibles (Fig. 7, b) hardly longer than broad (7 : 6), short, thick at base 
tridentate, all the teeth blunt and rounded, only[jthe basal one clearl 
Fig. 7. Trigonura tenuicaudis Waterst { $). 
a. ovipositor. 
b. mandible. 
c. ventral edge of hind femur. 
separated, the upper pair like two rounded contiguous lobes. Behind 
the upper teeth externally is a patch of 12 bristles and behind them again 
an irregular transverse row of about 6. Maxillae ; the stipes is evenly set 
with very numerous short bristles and there is only a single slightly 
larger bristle inside. Palpus 3, 3|, 4, 6|, joints 2-4 (especially the last) 
shorter than in ruficaudis and distinctly broader, the greatest breadth 
(2|-) occurs on the 4th joint. Mentum with 70-80 bristles ; labial palpus 
much as in ruficaudis {i.e., 1 and 3 subequal and each over twice as long 
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