324 MEMOIRS OF THE CARNEGIE MUSEUM 



Abdomen ovate, not longer than the thorax, the ovipositor not exsei-tcd, the second segment 

 (first body) occupying about one fourtli tlie wliole surface, the third segment small. 



Merisus Walker (type M. splendidtis Walk.). 



4. Abdomen ovate, the dorsum usually Hat, the second segment not occupying one fourth the whole sur- 



face, segments 3-6 subequal Homoporus Thomson (type Pleromalus fuMvenh-ia Walk.). 



5. Metathorax not ending in a subglobosc neck 6 



Metathorax ending in a subglobose neck. 



Abdomen subrotund or short ovate, the second segment large, occupying one lialf or more of 

 the whole surface ; antennse filiform, clothed with a short, fine pubescence. 



Micromelus Walker. 



6. Marginal vein always distinctly longer than the stigmal vein 7 



Marginal vein riot or scarcely longer than the stigmal vein 8 



7. AntenuiT? at apex stylate ; abdomen oval, depressed Pliaenacra Forster. 



Antenna; at apex normal ; abdomen oblong, narrowed, the second segment not quite as long as the 



three following united, which are short and subequal, the fourth very slightly the longest ; antenna; 

 filiform, rather densely pubescent Merisus Walker. 



8. Abdomen short, spatulate, the second .segment as long as or a little longer than the three following 



united, which are very short, the third the longe.st ; antennre filiform, densely pubescent. 



Homoporus Thomson. 



Tribe III. Isoplatini. 

 In this trilie tlie mesonotal farrows are always di.stinct, complete, while the an- 

 tennae are usually inserted far anteriorlj' near the mouth border. 



TABLE OF GENERA. 



1. Females 2 



Males 5 



2. Non-metallic ; mandibles variable, sometimes edentate 3 



Metallic ; mandibles dentate. 



Abdomen compressed, the ventral valve prominent ; stigmal vein as long as the marginal, end- 

 ing in a small knob Isoplata Forster (type I. geniculata Forst). 



3. Mandibles acute, edentate -i 



Mandibles broad, dentate. 



Abdomen conic-ovate ; antennte short, strongly clavate, inserted near the mouth border, the 

 pedicel large ; stigmal vein as long as the marginal, clavate. 



CcElocyba Ashmead (type C. nigrocincla Ashm.). 



4. Abdomen .short, globose, depressed above ; marginal vein not or scarcely longer than the stigmal vein ; 



metathorax very short. 



Stigmal vein ending in a small knob ; abdomen with the first dorsal segment elongate, occupy- 

 ing half or more of the whole surface Terobiella A.shmcad (type T. flavifrons Ashm.). 



Stigmal vein ending in a moderately large knob ; abdomen with the dorsal segments short. 



Brachyscelidipliaga Ashmead (type B. flava A.shm.). 



.5. Non-metallic ; mandibles acute or broad, dentate (i 



Metallic ; mandibles dentate Isoplata Forster. 



G. Mandibles acute, edentate 7 



Mandibles broad, dentate. 



