22 MONOGRArHIA CHALCIDITUM. 



postscutellum maximum ; paraptera et epimera trigona ; ster- 

 num parvum : petiolus elongatus, linearis, abdomine brevior : 

 abdomen glabrum, gibbum, compressum, coarctatum, nonnun- 

 quam apice elongatum et acuminatum; segmentum l um . d max- 

 imum ; caetera breviora ; segmenta ventralia pauca maris abdominis 

 apicem versus conspicua : fern, lamina angusta segmenta omnia 

 ventralia et oviductum nisi ad apicem abscondit : propedes breves ; 

 trochanteres parvi ; femora subclavata ; tibiae apice spina elon- 

 gata valida armata ; ungues elongati, subarcuati : pulvilli mi- 

 nuti : mesopedes longiores et graciliores, caetera propedum : 

 metapedum coxae maxima?, elongatae ; femora maxima, ovata, 

 subtus dentibus plurimus armata, quorum basalis maxima ; tibiae 

 valde arcuatae, subtus canaliculatae, femoribus appressae ; apicis 

 angulus internus productus, acuminatus ; caetera propedum : 

 proalae nervus ordinarius ante medium costae junctus, hide 

 per costam fere ad alae apicem productus : nervi duo longitu- 

 dinales sinuati, indistincti, anticus furcam emittens ramulo 

 stigmaticali junctam : metalae angustae ; nervus ordinarius ultra 

 medium productus, apice bamo armatus. 



Divisio 1. Abdomen breve, vix longius quam latum. 



Latreille supposed that these insects infest the Stratiomydae, 

 or other Diptera, that are aquatic in their larva state. 

 C. xanthostigma, Dalrn. is parasitic upon a species of 

 Hylotoma. 



Sp. 1. Smi. nigrifex. Mas et Fern. Nigra, petiolo et pedi- 

 bus flavis, his nigro variegalis. 



Sphex nigrifex. . . Sulzer, Hist. Ins. 191. 1. fig. 21. 1. 



Vespa &c Geqffroy, Ins. Par. II. 380. 16. 



Vespa dearticulata. Fourc. Ent. Par. Tom. II. 437. 16. 

 Sphex sispes . . . Fabr. Sp. Ins. I. 446. 61. Fillers, Ent. 



Tom. I. 222. 6. 

 Chrysis sispes . . . Fabr. Syst. Ent. 359. 15. 

 Chalcis sispes . . . Fabr. Mant. Ins. I. 272. 1. Ent. Syst. 



II. 194. 1. Syst. Piezat. 159. I. 



Gmel, Syst. Nat. I. 5. 2742. 1. 



Hubn. Naturf. 24. 54. 18. Tab. 2. 



rt The second segment of my preceding descriptions ; the petiole being con- 

 sidered as the first. The other alterations require no explanation. 



