THE BOMBYCINA. Ill 



especially strong and membranous, in order that it can grasp 

 the twigs safely. 



The emperor moth has a veiy pretty larva, which is often 

 found upon heather in the summer. It is green, and each 

 segment has seven pink tubercles on black rings, and each 

 tubercle has a tuft of short black hair. The spiracles are 

 orange in colour. 



The caterpillars of Attaais cecropia, from Louisiana, are 

 remarkable for the changes they undergo in moulting, before 

 transforming themselves into pupae. 



At their birth they are almost black, and are decorated with 

 verticiUate hairs, which make them look like little hedgehogs. 

 After a few days their general colour becomes clearer and lighter, 

 and the tubercles which support the hairs become more promi- 

 nent. The skin is then moulted, and the new one succeeds, and 

 is of a grey green or russet colour, and all the tubercles and spines 

 are brilliantly black. Moulting again occurs, and, behold, a light 

 green creature appears, with five rows of black spots ; two mag- 

 nificent tubercles of a carmine colour are to be observed on the 

 second and third segments, and two of a light yellow are situated 

 upon the dorsal part of every other segment. Each tubercle 

 carries several verticiUate hairs, which are black. A third moult 

 finds the body becoming an azure blue on the back, with black 

 spots on the sides and head ; the tubercles form two rows on the 

 back, and are much enlarged ; they are red in colour, and the other 

 tubercles have a single spine upon them. Finally the last moult 

 takes place, and the caterpillar turns out to be of a ps^Ie green 

 colour, with all the lateral tubercles of a light green, and the red 

 tubercles have taken on an orange tint, and have only one spine. 

 These changes of colour and of the development of tubercles 

 and hairs during the skin-shedding are indeed most remarkable. 



The cocoons of these caterpillars are double. There is an 

 envelope, hard, and like parchment in its texture, which can readily 

 be separated from the inner and silky one. 



An Attacus, whose moth, larvae, and cocoon are represented in 

 the engraving, is called Attacus liina, and is celebrated for the 

 fine silk of its caterpillar, which feeds especially upon the Liquid- 

 ambar trees of Carolina and Florida. 



