8 Mr. Westwood's Observations on the Genus Derbe. 



costalis, puncto rotundo ad basin furcse apicalis trifidae venae postcostalis, venis qua- 

 tuor transversis discoidalibus, punctisque quatuor marginis interni nigris ; posticte 

 puncto parvo inter venam medianam et primam analem venaque transversa versus 

 apicem nigris ; lunula parva fuscescenti inter omnes venas ad marginem posticum ala- 

 rum omnium. Vena postcostalis alarum postiearum apice bifida. 



Mysidia lactiflora. fVestw. 



Tab. I. Fig. 4. 



Luteo-albida ; vertice collarisque margine antico parum sanguineis, hujus te- 

 gularumque marginibus posticis albis, alis albis margine antico lutescenti 

 basin versus maculis tribus parvis maculaque majori ante apicem nigris. 



Long. Corp. lin. 2^. Expans. alar. lin. 12^. (mens. Angl.). 



Habitat in Brasilia. In Mus. Westw. 



Totalutescenti-albida; capite parvo; oculis fuscis; vertice pariim sanguineo; antennis longis, 

 albis. Collare album, margine antico luteo-sanguineo. Tegulm magnae, postice albae. 

 Mesothorax postice albus. Pedes omnes albidi. Ala albae, apicem versus albido tinctae, 

 pulverosEe, pariim translucidae, venis pallidis ; antica costa luteo-albida, punctis tribus 

 nigris ante medium, punctis duobus minutis ante apicem in ramis trifidis apicalibus 

 venae postcostalis, punctoque majore rotundato in vena transversa ramos duos posti- 

 cos venae postcostalis conjungente, nigris, venis tribus transversis discoidalibus fusco- 

 tinctis, macula parva nigra versus marginis interni basin ; al<e posticx venis duabus 

 transversis punctoque parvo versus angulum analem nigris, vena postcostali ad apicem 

 bis bifida. 



The last of the Fabrician species of the genus Derbe, D. elongata, is an 

 inhabitant of New Holland, and recedes so much from the type of the genus, 

 especially in the form and veining of the wings, that it is necessary to esta- 

 blish a distinct subgenus for its reception. This insect was described by 

 Fabricius from the Banksian cabinet, now in the possession of the Linnean 

 Society, in which are preserved three specimens, from which the accompany- 

 ing figure is taken. The following characters distinguish it from tlie other 

 subgenera of this group. 



