212 HALIDAY ON 



subtus excisae : gense apice, prothorax, sutureeque thoracis la- 

 terales rufo-piceae : metathorax abdominisque segmentum 1 ru- 

 gulosa, hoc basi piceum: alae hyalinae stigmate nervisque fuscis: 

 stigma latius quam Sp. 25, attenuato-trigonam, cubiti abscissam 

 interiorem opprimens: areola cubitalis 2 quam illi longior, extror- 

 sum parum attenuata : postica disci clausa : nervi recurrentis in 

 alis posticis vestigium nullum. 

 Habitat prope ripas Senani autumno semel lectus. 



FF. Mesothoracis dorsum foveola antescutellari impressum, sulcis 

 humeralibus inchoatis tantum. 



Conferendus O. reconditor, No. 29 post. 



Sp. 24. O. aethiops. Niger, mandibulis rufis, pedibus piceis, 

 femoribus anticis apice et tibiarum basi dilutius, mas. (Long. 

 i lin.) 



Antennae corporis longitudine 21-articulatae nigrse : palpi breves 

 fusci : metathorax medio laevis nitens : abdominis segmentum 1 

 sublineare punctulatum, reliqua laevissima: alae hyalinae, stig- 

 mate nervisque fuscis : stigma angustum fere lineare : areola 

 radialis ante apicem alee clausa, cubitalis 2 longa vix apice 

 attenuata, postica disci haud perfecte clausa : nervi recurrentis 

 vestigium in alis posticis 0. pygmceatori, mas, prima facie similis, 

 differt sculptura, alis hyalinis, areola radiali strictiore, cubitali 

 vero longiore. 



Sp. 25. O. pactus. Niger, antennarum scapo mandibulis 

 pedibus abdominisque segmento 2 antice rufo-testaceis, fern. 

 terebra subexerta. (Long. 1 lin.) 



Antennae corpore paulo longiores 29-articulatse : metathorax abdo- 

 minisque segmentum 1 rugosa, opaca, hoc basi utrinque carinatum : 

 alarum stigma angustum lineari - lanceolatum : cubiti abscissa 

 prima brevissima extricata : alae latiores quam O. spreti (cujus 

 simillimae,) et areola cubitalis 2 minus attenuata: nervi recur- 

 rentis in alis posticis vestigium nullum. 



Habitat prioribus olim commixtus. 



Sp. 26. O. aemulus. Niger antennarum basi late ore pedibus 

 abdominisque segmento 2 antice testaceis terebra exerta brevi, 

 fem. (Long. 1 lin.) 



Antennae graciles corpore longiores 27-articulatae testaceee apice 

 fuscse : oris rima tenuis : clypeus et mandibular testaceae : 



