258 LEPIDOPTEKA. 



maturity, are females, tliey will give forty-five millir 

 caterpillars in the second, and six thousand seven hii 

 and fifty millions in the third generation. These data 

 to show that the actual nvmiber of these insects, exist: 

 any one time, must be far beyond the limits of calcu 

 The greater part of caterpillars subsist on vegetable 

 and especially on the leaves of plants ; hence their ir 

 to vegetation are immense, and are too often forced 

 our notice. Some devour the solid wood of trees, son 

 only in the pith of plants, and some confine themsel 

 grains and seeds. Certain 'species attack our woollen 

 fiirs, thereby doing us much injury ; even leather, 

 Avax, flour, and lard afi:ord nourishment to particular 

 of caterpillars. 



Caterpillars vary greatly in form and appearance 

 in general, their bodies are more or less cylindrical 

 composed of twelve rings or segments, with a shelly 

 and from ten to sixteen legs. The first three pairs o 

 are covered with a shelly skin, are jointed and tap 

 and are armed at the end with a little claw ; the othe 

 are thick and fleshy, without joints, but elastic or contr 

 and are generally surrounded at the extremity by nun 

 minute hooks. There are six very small eyes^ on 

 side of the head, two short antennse, and strong ja' 

 nippers, placed at the sides of the mouth, so as to ope 

 shut sidewise. In the middle of the lower lip is a 

 conical tube, from which the insects spin the silken tl 

 that are used by them in making their nests and the 

 coons, and in various other purposes of their economy, 

 long and slender bags, in the interior of their bodies 

 ending in the spinning tube, contain the matter of th( 

 This is a sticky fluid, and it flows from the spinner 

 fine stream, which hardens into a thread so soon as it < 



[2 Though Dr. Harris mentions the " eyes " of caterpillars, yet be it 

 stood, he does not assert that they see. It is very doubtful whether they h 

 faculty of vision. — Muiuas.] 



