1840.] L'iiineua Society. 83 



He accordingly restricts the generic name Derbe to the typical spe- 

 cies, with the following characters : 



Derbe. Rostrum ad medium abdominis extensum, aiticulo apicali minute. 

 Antennas breviores. Oculi subrotundati. Alse longiores, angustiores, 

 costa anticarum ante apicem incisa, venis numerosis, longitudinalibus, 

 in medio venis transversis conjunctis, mediana ramos lOlongitudinales 

 emittente ; alae posticas vena postcostali 4-fida. 



In addition to the typical species and D. nervosa, Klug, Burm., 

 the author adds the two following species to the typical group : 



1. D. semistriaia, luteo-fulva ; alis paUidis costa magis fidvescenti venis 

 nigricantibus strigisque tenuibus fuscis inter venas (nisi in cellulis api- 

 calibus) dispositis. Expans. alar. lin. 16J. Brasilia. Mus. Westw. 



2. Z). strigipetmis, pallide fusco-lutea ; thoracis dorso carinaque faciei 

 sanguineis, alarum venis fuscis, strigls tenuibus fuscescentibus inter 

 venas omnes ad apicem alarum carentibus, pedibus albidis. Expans. 

 alar. lin. 14. Brasilia. Mus. Westw. 



Mysidia. Rostrum ultra pedes posticos baud extensum. Antennae me- 

 diocres. Oculi rotundati. Alae breviores, latiores, pulverosae ; anticEe 

 integrae, venis paucioribus, vena mediana ramos tres emittente, ramo 

 medio bifido ; posticae 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. Fab., (described and 

 figured by Percheron from the Copenhagen Cabinet as the type of 

 the genus,) D. squamigera, Fab., D. costalis. Fab., and probabl)'' 

 D. punctum. Fab., D. testacea, Fab., and D. nivea. Fab., as well as 

 the following new species : 



M. albipennis, parva, tenera ; alis albis, anlicis puncto parvo ante me- 

 dium costae punctis nonnullis ad marginem internum venis trans- 

 versis punctoque ante apicem nigris, lunulis parvis marginalibus fuscis. 

 Expans. alar. lin. 8. Vera Cruz. Mus. Westw. 



M. lactifora, luteo-albida ; vertice coUarisque margine antico parum 

 sanguineis, hujus margine postico margineque postico tegularum albis, 

 alis albis margine antico lutescente versus basin macuUs tribus parvis 

 maculaque majori ante apicem nigris. Expans. alar. lin. 12^. Brasilia. 

 Mus. Westw. 



M. suhfasciata, alba ; alis fusco transverse nebulosis puncto ante apicem 

 nigro ad basin areae parvae triangularis subapicalis, venis 4 transversis 

 obscuris. Brasilia. Mus. D. Burchell, et Soc. Zool. Lond. 



