27 [ 175 3 



CHAPTER T. 



NATURAL HISTORY OF THE SILKWORM. 



The phalaena, or moth of the silkworm, or, more properly, the silk- 

 caterpillar, is about an inch long, and nearly an inch and a half be- 

 tween the extremities of the largest wings, when extended. The bo- 

 dies of both male and female, are obscurely white, and thickly covered 

 with short hairs. There are tvvo antennae;* the stems are whitish, and 

 lateral fillets pectinated, or like the teeth of a comb. In the male, 

 they are unequally spaced, while in the female, they are smooth, less 

 pectinated, shorter, and not so close, and, in a state of repose, they 

 commonly lie on their sides. There are four transparent wings, of 

 the same color as the body. In the male, the upper surface of the su- 

 perior wings are crossed by two brown bands; the broadest one is near 

 the extremity of the wing, and is continued on the under wing. Both 

 bands are bordered with a line: on the under surface there is only one 

 band. The superior wings are a little bent downwards at their ends. 

 The inferior wings of both are reverse in a state of rest, and extend 

 beyond the upper ones. The wings are covered with a white powder. 



The tail of the male is somewhat raised and square. The female i,s 

 larger than the male; her wings are less strongly marked with bands, 

 and on the exterior margin of the wings. On the wings of both, are 

 several rays, which are as apparent on the under as the upper surfaces. 

 These are termed nervures, and are hollow tubes, proceeding from 

 the commencement of the wings, and diminish gradually in size, (the 

 marginal one excepted) to their termination. The vessels contained in 

 these nervures, consist of spiral threads, whence they appear to be in- 

 tended to be air vessels communicating with the air vessels in the 

 body.! The wings are flat, and incapable of contraction or dilatation. 

 There are two black convex eyes, one on each side of the head. They 

 are protuberant, and rise above the head rather more than a hemi- 

 sphere. To the naked eye, their surface appciirs to be plain; but, by 

 submitting them to the microscope, their true and admirable structure 

 is ascertained. By the help of this instrument, it is found that the 

 whole surface consists of a multitude of lenses, all separated from one 



* The antenn?e are commonly called feelers, from the circumstance of numerous 

 Tnsects touching- substances with them; but all antennse are not thus used, nor are 

 they formed to answer this purpose. 



It is now supposed that they are, in some way, connected with the organ of hear- 

 ing; and that they may collect and transmit sound to such an organ, the minuteness 

 of which defies investigation. This organ is suspected to be at the base of the an- 

 tenn?e, the spot in which the same organ has been discovered in tlie crayfish. Kirbv 

 and Spence on Insects, vol. 3. pp. 43. 46, vol. 4. p. 246. 



■\ These nervures are not peculiar to the iHoth of the silk-caterpillar, lint conimon 

 to the wings of most insects. 



