HEPIALID^. 3 



dust, &c. witli their coccoons, or construct them of slight silken 

 materials, while others are furnished with the means of forming a 

 hard semi-transparent case, in which they change to pupae. Although 

 several of the species are crepuscular insects, many of the Bom- 

 bycidse commence their aerial excursions in the afternoon, when 

 they may be observed flying with great velocity, and describing 

 large undulated tracks in their course. 



In dividing this section into four families only, I am in doubt 

 whether the Saturnise should not be separated from the Bombycidse, 

 from which they differ by their broad horizontally extended wings, 

 short deeply pectinated antennae (serrated in the female), and by 

 the nudity of the larvae, which have merely a verticillated series 

 of hairs on each segment. 



r moniliformes, aut setacea; : . .1. Hepialid^. 

 rnuUae: Antennoc^ 

 Mavilla:^ C. pki^™<iue bipectinatae : . . 3. BombyciDjE. 



C plus minus ve con- r brevissimi: . . . .2. Notodontid^. 

 spicucB, . . •? 



t. breves, submembranaccEE : . . 4. Aectiid^k. 



Family I.— HEPIALID^. 



AnteniwB short, moniliform, simple, or furnished with a single row of den ti di- 

 lations, or cilia ; sometimes rather elongate, pectinated, or tomentose at the 

 base, with the apex simple : tongue M^anting : palpi none, or distinct : wings 

 deflexed, long, and narrow : thorax not crested. 



Larvse reside in the interior of vegetables; fleshy, naked, with six pectoral, 

 eight abdominal, and two anal feet : pupa with the segments denticulated on 

 the sides. 



That the Hepialidse are closely allied to the Sphingidae may be 

 shown by a reference to the genus Smerinthus, which bears con- 

 siderable resemblance to some of the gigantic individuals of this 

 family: in Smerinthus the tongue is very short, the thorax and 

 body stout and thick, the antennae rather short, more or less ser- 

 rated, and the wings strongly nerved ; characters which obtain more 

 or less amongst the Hepialidae : again, the habits of the larva are 

 not widely dissimilar to those of the ^geriidae ; the larvae of the 

 genera Cossus and Zeuzera perforating the solid wood of trees, 

 while those of Hepialus devour roots. 



The British genera may be thus distinguished : 



r subfiliformes ; thorace multo breviores : . . .31. Hepialus. 



^setaceae; thoracis longitudine, f internt; dcnticulati : . 33. Cossus. 

 V, apice . . ' • \ 



^simplici: . . .32. Zeuzeha. 



b2 



