LEPIDOPTERA. 275 



Sdme caterpillars with fourteen or sixteen feet, bvit of which some of 

 the intermediate membranous ones are shorter than the others, have 

 been called pseudo-geometrce. The membranous feet are frequently 

 terminated by a more or less complete crown of little hooks. 



The body of these larvae are generally elongated, almost cylin- 

 drical, soft, variously coloured, sometimes naked, and sometimes 

 covered with hairs, tubercles aud spines. It is composed of twelve 

 segments or annuli, exclusive of the head, with nine stigmata on each 

 side. Their head is invested Avith a corneous or squamous dermis, and 

 presents on each side six shining granules, which appear to be ocelli; 

 it is also furnished with two very short and conical antennae, and a 

 mouth composed of strong mandibles, two maxillae, a labium, and four 

 small palpi. The silk they employ is elaborated in two long and 

 tortuous internal vessels, of which the attenuated superior extremi- 

 ties terminate in the lip. A tubular and conical mamilla is the 

 s])indle through which the threads are spun. 



Most caterpillars feed on the leaves of plants ; some gnaw their 

 flowers, roots, buds, and seeds; others attack the ligneous or hardest 

 part of trees, softening it by means of a fluid which they disgorge. 

 Certain species attack our woollens and furs, thereby doing us much 

 injury: even our leather, bacon, wax, and lard are not spared by 

 them. Several confine themselves exclusively to a single article of 

 diet ; others are less delicate, and devour all sorts of matters *. 



Some of them form societies, and frequently live under a silken 

 tent, spun by them in common, which even shelters them during the 

 winter. Several construct sheaths for themselves, either fixed or 

 portable. Others make their abode in the parenchyma of leaves, 

 where they form galleries. The greater number are diurnal. The 

 others never issue forth but at night. The severity of winter, bO 

 fatal to almost all Insects, does not affect certain Phalaenae, Avhich 

 only appear in that season. 



Caterpillars usually change their skin four times, previously to 

 passing into the state of a nyuiph or chrysalis. Most of them spin a 

 cocoon in which they enclose themselves. A frequently reddish 

 liquor or sort of meconium, which Lepidopterous Insects eject per 

 anum, at the moment of their metamorphosis, softens or weakens the 

 extremity of the cocoon, and facilitates their exit ; one of these 

 extremities also is generally thinner than the other, or presents a 

 favourable issue, by the peculiar disposition of the fibres. Other 



* One of the most evident proofs of the Divine Providence is the perfect coin- 

 cidence of the appearance of the caterpiil^r with that of the plant on which it is 

 to feed. 



