468 CHARACTERS OF SOME UNDESCRIBED 



nervis dilute fuscis, squamulis fusco-ferrugineis. (Long. corp. 

 1 lin. ; alar. 2|.) Caput thoracis, &c. — (ut antea, descriplionis 

 ulterioris his emendatis,) — Oculi pilis raris subtilissimis erectis 

 consiti : abdomen thoracis fere longitudine et latitudine, ovato- 

 orbiculatum subdepressum laeve : segmenta dorsi octo, anteriora 

 longitudine subsequalia, posteriora lineari-transvera : primi scutum 

 gracillimum (adhuc gracilius quam Microgastri laterali), apice 

 attenuatum, latera membranacea late retecta : sextum ventrale 

 leviter carinatum et apice productum, aculeum subexertum 

 fulciens. 

 Habitat in Spartis scopario. 



Vol. II. p. 252. Sp. 45. Micr. intricatus. b Vespa, &c. 

 Ray Ins. 255. 13. 



Art. XLIII.- — Characters of some undescribed New Holland 

 Diptera. By Francis Walker. 



Megistocera. — Wiedemann. 



M. dispar. Mas et Fern. Mari antennce longissimce, fem. 

 brevissimce. Propter femina antennas brevissiraas Magis- 

 tocera non bene convenit, at vix genus diversum. 



Mas. — Ferruginea, pubescens : oculi nigro-fusci : palpi nigri : antenna? 

 fuscse, pubescentes, corpore fere quadruplo longiores ; articuli l us . 

 et 2 US . omnino 3 US . que basi ferruginei : thorax subtus pallidior : 

 mesothorax vittis supra 3 pallidis : abdomen utrinque fusco fas- 

 ciatum, apice obscurius : pedes ferruginei, longi, graciles, pubes- 

 centes, femora et tibiae apice tarsique nisi ad basin fusca : alee 

 hyalinae, iridescentes, basi et ad costam fusco-flavae ; squamulae et 

 nervi flava, hi ad apices plerumque fusci : halteres flavi, apice pal- 

 lide fusci. 



Fem. — Mari similis at obscurior, thorax angustior, abdomen longius, 

 pedes breviores, alse paullo breviores et angustiores : antenna? 

 obscure fuscae, capite breviores ; articuli l us . et 2 US . ferruginei : 



b In the course of last autumn, Mr. Curtis and I found the follicles of this 

 species in profusion, attached to springs of heath, grass, &c. in the Western 

 Isles. The caterpillars of Mamestra Phi were wandering about the same places, 

 and to them probably the '' Eruca viridis lineolis albicantibus" of Ray should be 

 referred. Two species of TIemiteles, and one of Pezomachus, were produced in 

 abundance out of these follicles, along with the Microgaster. 



