51 IIAUSTELLATA. — I-El'IDOPTEIiA. 



Family IV.— ARCTIID^E, Leach. 



Palpi two, rather small, mostly triarticulate, pilose ; rarely wanting : maxiUae 

 generally short, somewhat membranaceous, sometimes obsolete. Antennw mo- 

 derate, bipectinate or ciliated, sometimes serrated, the pectinations simple or 

 ciliated, and furnished with one or more bristles at their apex : thorax rarely 

 crested, stout : body not very robust ; the apex of the males usually tufted, 

 and of the females occasionally furnished with a woolly mass: wings deflexed, 

 or horizontal, entire. Males usually smaller, but not unfrequently larger, than 

 the females. Larva; generally very hairy, frequently ornamented with several 

 compact tufts of hair on the back, and elongate ones on the neck or tail ; 

 occasionally naked, enclosed in a covered moveable case, or free : piipa various, 

 mostly foUiculated. 



The insects which I have included in this family are considerably- 

 diversified in habit, and I do not feel satisfied with the location of 

 several of the geneva; but, without materially increasing- the number 

 of families, no better situation presents itself for their reception ; 

 their diversities will be hereafter pointed out : it may be suflScient 

 to notice in this place, that the typical genera form the genus 

 Arctia of Schrank, a name imposed by him from the hairiness of 

 their larvee, and which has consequently been used to designate 

 the family. As among the Bombycidse, the^larvse of many genera 

 are gregarious, and the males of the perfect insect assemble in 

 search of their virgin females, and fly with great celerity in the 

 afternoon. One group, Psyche and its congeners, approaches closely 

 to the Hepialidse ; and another, Limacodes and Heterogenea, to the 

 first group of Bombycida?, the cause of which will be rendered very 

 evident by an inspection of the diagram in my catalogue : these 

 groups differ materially from the true Arctiidse and from each other, 

 and offer some most interesting facts, which will be subsequently 

 detailed. 



If the two great genera, Laria and Arctia of Schrank, require 

 further division (and such appears to be the universal opinion of 

 modern writers), it necessarily follows that, unless that subdivision 

 is carried on to the utmost, dissimilarly constructed species must 

 inevitably remain united : I have therefore been compelled to divide 

 the indigenous species into the following genera; which may be 

 known by the subjoined table, formed, as far as possible, from ex- 

 ternal characters. 



