Linnean Society. 477 
Read also, ‘“‘ Observations on the Genus Derbe of Fabricius.” 
By John O. Westwood, Esq., F.L.S. 
After noticing the recent memoirs by Messrs. Percheron and 
Boheman on this almost unknown Fabrician genus, and its very 
close relationship to Otiocerus and Anotia of Kirby, the author shows 
that the Fabrician type of the genus D. hemorrhoidalis is quite 
distinct from the group described by the two first-mentioned 
authors as its type. He accordingly restricts the generic name 
Derbe to the typical species with the following characters : 
Derze. Rostrum ad medium abdominis extensum, articulo apicali minuto. 
Antenne breviores. Oculi subrotundati. Alz longiores, angustiores, 
costa anticarum ante apicem incisé, venis numerosis, longitudinalibus, 
in medio venis transversis conjunctis, mediana ramos 10 longitudinales 
emittente; alz posticee vend postcostali 4-fida. 
In addition to the typical species and the D. nervosa, Klug, 
Burm., the author adds the two following species to the typical 
group: 
' 1. D. semistriata, luteo-fulva ; alis pallidis cost&é magis fulvescenti venis 
nigricantibus strigisque tenuibus fuscis inter venas (nisi cellulis apica- 
libus) dispositis. Expans. alar. lin. 163. Brasilia. Mus. Westw. 
2. D. strigipennis, pallidé fusco-lutea; dorso thoracis et carina faciei 
sanguineis, alarum venis fuscis strigisque tenuibus fuscescentibus inter 
venas omnes, ad apicem alarum carentibus, pedibus albidis. Expans. 
alar. lin. 14. Brasilia. Mus. Westw. 
Mysip1a. Rostrum ultra pedes posticos haud extensum. Antenne me- 
diocres. Oculirotundati. Alz breviores, latiores, pulverose ; anticze 
integrze, venis paucioribus, vend mediana ramos tres emittente, ramo 
medio bifido; posticze vena postcostali bifida aut trifida. 
The variation in the position and number of the veins of the 
wings, affording a character of primary importance for distinguish- 
ing the preceding groups, the author has at some length entered 
into an examination of their normal state and direction, and the 
manner in which they become modified. The following species are 
referred to this subgenus: Derbe pallida, Fabr., (described and 
figured by Percheron from the Copenhagen Cabinet as the type of 
the genus), D. squamigera, Fab., D. costalis, Fab., and probably 
D. punctum, Fab., D. testacea, Fab., and D. nivea, Fab., as well as 
the following new species : 
M. albipennis, parva, tenera; alis albis anticis puncto parvo ante me- 
dium costz, punctis nonnullis ad marginem internum venis trans- 
_versis punctoque ante apicem nigris lunulisque parvis marginalibus 
fuscis. Expans. alar. lin.8. Vera Cruz. Mus. Westw. 
M. lactiflora, luteo-albida; capitis vertice et collaris margine antico 
parm sanguineis, hujus margine postico et margine postico tegula- 
rum albis, alis albis margine antico lutescente versus basin maculis 
tribus parvis maculaque majori ante apicem nigris. Expans. alar. 
lin. 123. Brasilia. Mus. Westw. 
M. subfasciata, alba; alis fusco transversé nebulcsis punctoque ante 
apicem nigro ad basin arez parve triangularis subapicalis venisque 4 
transversis obscuris. Expans. alar. lin. Brasilia. Mus. D. Burchell, 
et Soc. Zool. Lond. 
