142 FAMILY OTNIPID2B. 



breadth to the thorax. Their most important distinc- 

 tive features are : 



The abdomen pedunculafced ; trochanters biarticu- 

 lated ; antennae twelve- to fifteen- jointed, and never 

 elbowed ; prothorax reaching to the insertion of the 

 wings ; wings without a stigma, and with one radial 

 and one to three cubital cellules, the second, when 

 present, being minute, usually triangular ; the sub- 

 costal cellule large, always present, the other cellules 

 badly defined or absent ; submarginal nervure absent ; 

 abdomen compressed ; ovipositor originating close to 

 the base of the abdomen, the borer usually semi-spiral, 

 and with the parts free ; larva apterous, never spin- 

 ning a cocoon ; eggs stalked. 



The species are small in size, seldom exceeding 5 

 m.m. in length, and often not more than 2 m.m. As a 

 whole they form a well-defined group, possessing suffi- 

 cient characteristics which enable the species to be 

 readily recognised from the other groups of Hymen- 

 optera with petiolate abdomen. The Ghalcididse are 

 easily separated from them by the wings having a 

 stigma and neither a radial nor cubital cellules, by the 

 antennae being elbowed, and by the prothorax not 

 reaching to the insertion of the wings. The Oxyura 

 agree in the prothorax reaching to the tegulae, but 

 differ in the antennae being elbowed, in the wings 

 generally having a stigma, and in the ovipositor issu- 

 ing from the point of the abdomen. The Jtraconidx 

 and IchneumoniddB both possess a stigma, and differ in 

 many other points from the Cynipidx. 



The Mouth Organs. The mandibles are short, broad, 

 quadrangular, and bear one, two, or three teeth, either 

 one large apical tooth separated by a deep depression 

 from the basal part, as in Gynips ; two large, acute, 

 bent teeth, as in JEgilips, or three teeth as in Figites. 

 Frequently the teeth are not alike. The labium is 

 entire, fleshy, and truncated, or with a curve at the 

 top. The maxilla has usually a large, broad, fleshy 

 outer lobe, the inner lobe obsolete. The labial palpi 



