238 LEriDOPTERA. 



convolutions. The colon is constantly of a large size, and is 

 often dilated into a caecum at its anterior portion." (Siebold.) 

 The salivary glands are composed of two simple tubes, which 

 are very large in the larval state, extending into the abdomen. 



The respiratory system is normal and well developed. In 

 the larva the stigmata are wanting on the second and third 

 thoracic and last abdominal segment. In those species of 

 SjyhingidcB, Bomhycidm and ^oc^rn' dee, which have a 

 long-sustained flight there are numerous vesicular dilatations 

 of the trachea?. 



The urinary tubes are six in number ; they are long, free, 

 and open into the stomach by two excretory ducts. 



The silk-glands consist of two long, flexuous, thick-walled 

 sacs, situated on the sides of the body, and opening by a 

 common orifice on the under lip (labium) usually at the 

 extremity of a short tubular protuberance (Siebold). They 

 are most developed when the larva approaches the pupa state. 



We once found a larva of Clisiocampa Americana that had 

 just spun its cocoon, and to ascertain whether the silk had been 

 exhausted, we removed the worm from its cocoon, when it spun 

 another, but thinner one ; and upon removing it a second time 

 it spun a third very thin cocoon, before the supply of silk was 

 entirely exhausted. 



The ovar}^ consists of four ver}^ long, spiral, multilocular 

 tubes. The receptactdum seminis is pyriform, and often has a 

 long, spiral ductus seminalis. At its base is situated a large, 

 double sebaceous gland ; and there are two small ramose 

 glands, perhaps odoriferous, situated at the orifice of the vagina. 

 The copulatory pouch is a remarkably large, pyriform reservoir, 

 having for the reception of the male intromittent organ a 

 canal, which opens by a special orifice, situated below and 

 behind the external opening of the oviduct. (Siebold.) 



The testes form two round or oval follicles, and the two 

 short deferent canals finite with two simple and very flexuous 

 accessor}^ glands, to form the long ductus ejacuhitorius. 



Several interesting cases of hermaphroditism in butterflies 

 and moths have been published by European entomologists. 

 Mr. Edwards has noticed two remarkable instances in the Pro- 

 ceedings of the Philadelphia Entomological Society (vol. iv, 



