130 OrpER—HY MENOPTERA. 
pes anticus) ; ale antice cellula una marginali, 4 submarginalibus; prima magna accepit venam primam re- 
currentem, secunda parva trigona, tertia parva quadrata accepit venam secundam recurrentem ; cellulis 3 dis- 
coidalibus ; abdomen thorace paullo majus, depressum, subspatulatum ; segmento tertio ventrali in tubereulum 
medium conicum elevato, quarto inciso. 
NOMADINA SMITHII. 
(Westw. Trans. Ent. Soc. loc. cit.) 
PruatE XXIV, Fie. 7. 
Lutea, fusco varia: capite maculis 4 parvis inter et pone oculos; thorace linea media ad post-scutellum 
extensa, maculisque duabus oblongis mesothoracis, fuscis ; margine postico segmentoram abdominalium albido ; 
alis concoloribus, stigmate venisque castaneis. 
Long. corp. lin. 5; expans. alar. antic. lin. 10}. 
Habitat; Amazonia (Bates). In Mus. Smith. 
Gexus—RHOPALOSOMA. 
(Cresson, Proc. Ent. Soc. Philadelph. vol. iv. 1865, p. 58.) 
Caput mediocre, thoracis latitudine ; oculi ovales, margine interno incisura semicirculari (fig. 9@) ; ocelli 
magni; mandibule parve, 3-dentate (fig. 92); antenne ¢ graciles, filiformes, alis longiores, maris 13-, femine 
12-articulatz, non geniculate, articulo lmo parvo (fig. 9); palpi valde elongati, 6-4-articulati (fig. 9c, maxilla) ; 
labium, ut videtur, 3-lobatum (fig. 9d). Thorax elongato-ovatus, collare brevi, lateraliter ad tegulas extenso, in 
medio subtus profunde impresso (fig. 97); petiolus abdominis thorace longior; abdomen elongato-ovatum (fig. 
97, maris); pedes longi, graciles, haud spinoso-denticulati ; calcaribus tibiarum valde elongatis (fig.9 4); tarsis 
omnibus elongatis, simplicibus in maribus, membranaceo-dilatatis in foeminis (fig. 9%); unguibus dente medio 
subtus armatis (figs. 97, 9%); pulvilloque magno recurvo instructis ; alee mediocres, antic haud longitudinaliter 
plicate, cellula una marginali, 3 submarginalibus, prima et secunda equalibus, secunda accepit venam primam 
recurrentem valde obliquam in medio marginis postici; secunda recurrente, valde indistincta, cellulam ter- 
tiam discoidalem claudente, transversa, et apicem cellule secunde attingente; ale postice ad apicem vene 
pobrachialis incise. 
Syy.: Sibyllina. Westw. Trans. Ent. Soc. Lond. 1868, part iv. December, p. 329. 
This curious genus was considered (doubtingly) by the late Mr. Haliday (one of the most profound 
Hymenopterologists) as one of the Sphegidw, with smooth legs, near Pelopzeus, as appears by a note attached to 
a specimen of the type in the Collection of the British Museum}, 
On exhibiting a specimen of this insect at a meeting of the Entomological Society, I expressed an opinion 
of its relations embodied in the following passage, subsequently published in the Transactions of the Society :— 
‘Genus novum Aculeatorum, quoad affinitates animum excrucians, sed ad familiam Vespidarum ut mihi videtur 
magis approximans. Corpus elongatum, Belonogastri (Vespidarum) vel Pelopzi (Sphegidarum) habitu, etiam 
Formicarum nonnullarum antennis elongatis, non dissimile.’ 
Mr. F. Smith, on the same occasion, also considered that ‘it had more characters in accordance with those 
of the ants than with any other family.’ (Proc. Ent. Soc. Nov. 16, 1868.) 
Mr. Cresson, who first described this genus, placed it undoubtingly amongst the multitudinous genera of 
Ichneumonidze (which caused me to overlook it), remarking, ‘I am at present unable to define the true position 
of this remarkable genus. It seems to form a connecting link between the [chneumones genuini and the Adseiti ; 
from the former it differs by the paucity of the antennal joints, and from the latter, by the anterior wings 
having a faint indication of a second recurrent nervure. Its structure places it, beyond doubt, in the family 
Ichneumonide, whilst its general appearance, together with the arrangement of the wing-veins, seems to place it 
among the Adsciti, where I will allow it to remain, for the present.’ 
Subsequently, Mr. Smith (without being aware that the insect had been thus commented upon by 
Ir. Cresson), in a paper communicated to the Entomological Society on the 4th Jan. 1869 (Trans. 1868, Proc. 
li.) discussed the affinities of this genus at length with great acumen, contending, ‘1st, That all wasps have 
‘* Antenne foem. not geniculate; hind wings incised at end of the pobrachial vein; fore wings with a third discal 
areole. See also form of thorax. I think a Sphegid, with smooth legs, near Pelopeus.’ (Haliday MS. in Brit. Mus.) 
