LEPIDOPTEROUS INSECTS. 18 



I. The two anterior feet shorter than the others, folded, not 

 ambulatory, in both sexes, or in the males only ; chrysalis 

 fixed by its posterior extremity, and suspended with the head 

 downwards ; central areola of the lower wings open poste- 

 riorly in many species. 



A. The central areola of the lower wings is always posteriorly- 

 closed ; the two anterior feet, although small and folded, very 

 similar to the others ; the lower wings in general scarcely 

 embracing the abdomen below ; labial palpi slightly elevated 

 above the hood, much separated, slender, cylindrical. 



The genera are DANAUS, IDEA, HELICONIUS, and ACREA. 



B. Central areola of the lower wings open in many species ; 

 two anterior feet often minute and concealed, or apparent 

 and very hairy ; lower wings embracing the abdomen below ; 

 labial palpi rising above the hood, slender and cylindrical, 

 and not distant. 



a. Central areola of the lower wings open posteriorly. 



* The labial palpi are either separated through their whole 



length, or merely at their extremity, and abruptly terminated 



by a slender and a circular joint. 



2. Perlata. 



The genera are CETHOSIA and ARGYNNIS. 

 ** The inferior palpi are contiguous through all their extent, 

 and not terminated abruptly by a slender and acicular joint. 

 \- The antennae are terminated in a small club, in the form of 

 a button, short, turbinated, or ovoid ; caterpillar thickly 

 beset with spines. 



Contains one genus, VANESSA. 



j--|- Antennae terminated in an elongated club, or nearly fili- 

 form ; caterpillar naked or slightly spinous, with the poste- 

 rior extremity terminated in a bifid point. 



The genera are LIBYTHEA, BIBLIS, NYMPHALIS, and 

 MOKPHO. 



