130 STATES OF INSECTS. 



maxillary. The latter never exceed four joints % which 

 seems the most natural number; and the former are limit- 

 ed to three. Both vary between these numbers, and one 

 joint. The joints, though commonly simple, are sometimes 

 branched. This is the case with one I met with in con- 

 siderable numbers upon the Turnip, in October 1808, 

 the second joint of the palpi of which sends forth near 

 the apex an internal branch. In the larva of the Cossus, 

 as Lyonnet informs us b , the joints of the palpi are re- 

 tractile, so that the whole of the organ may be nearly 

 withdrawn. 



After thus describing the head of larvae, and its prin- 

 cipal organs, we must next say something upon the re- 

 mainder of the body, or what constitutes the 



2. Trunk and Abdomen : which I shall consider under 

 one article. These are composed of several segments or 

 rings, to which the feet and other appendages of the 

 body are fixed. The form of these segments, or that of 

 their vertical section, varies considerably: in many Lepi- 

 doptera, the wire-worm, &c, it would be nearly circular; 

 in others a greater or less segment of a circle would re- 

 present it ; and in some, perhaps, it would consist of two 

 such segments applied together. Their lower surface is 

 generally nearly plane. Their most natural number, 

 without the head and including the anal segment, is 

 twelve: this they seldom excee v d, and perhaps never 

 fourteen. The three first segments are those which re- 



a At first in the Bytisci they appear to have five joints ; but, as I 

 before observed, the first joint must be regarded as representing the 

 maxilla. 



b Lyonnet Anatom. 55, 58. 



