292 



LEPIDOPTERA. 



Thyridopteryx. It constructs an oval cocoon (Fig. 223d) 

 which hangs to the edge of the leaf. 



The genus Perophora, another sack-bearer (P. Melsheimerii 

 Harris), is a gigantic Psychic!, being about the size. of the silk- 

 worm moth, which it closely resembles in the imago state. It 

 also lives in a case during the larva state, formed of two oblong 

 pieces of leaf, fastened together in the neatest manner by their 

 edges, and lined with a thick and tough layer of brownish 

 silk. The larva is cylindrical, as thick as a common pipe-stem 

 gc^a and light reddish brown in color. 

 The head has extensible, jointed 

 feelers which, when extended, are 

 kept in constant motion, while be- 

 hind is a pair of antenna-like organs, 

 broad and flattened at the end. The 

 Fig. 224. tail is widened and flattened, form- 



ing a circular horny plate, which like the operculum of a whelk, 

 closes lip the aperture of the case. Before transforming within 

 its case, the larva closes each end with a circular silken lid. 

 The pupa is blunt at the hinder end and with a row of teeth on 

 each abdominal ring. Both sexes are winged. Our species, 

 P. Melsheimerii Harris, is reddish ash gre} r , sprinkled with 

 blackish points, and with a common oblique blackish line. 



Notodonta and its allies (Ptilodontes Hubner) are mostly 

 naked in the larva state, with large humps on the back, and the 

 hind legs often greatly prolonged, as 

 in Cerura, the "fork-tail." The pupa 

 and moths are best described by stat- 

 ing that they bear a close resemblance 

 to the Noctuids, for which they are 

 often mistaken. 



Coelodasys (Notodonta) unicornis 

 Smith derives its specific name from the horn* on the back of 

 the caterpillar, and its generic name from the large conical tuft 

 of hairs on the under side of the prothorax. The moth is light 

 brown, with irregular green patches on the fore wings. The 

 cocoon is thin and parchment-like, and the caterpillars remain 

 a long time in their cocoons before changing to pupae. Nerice 

 bidentata Walker (Fig. 224) is a closely allied moth. Edema 



Fig. 225. 



