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foot-stalks, assuming on the borders the form of scales 

 or hairs. The head is furnished with two large eyes, 

 which, seemingly composed of fifteen thousand cornea, 

 resemble the facets of cut glass. Butterflies have no 

 teeth ; a proboscis, which can be contracted or extended 

 at pleasure, serves them for extracting the sweet juices 

 of trees or flowers on which they feed, and is composed 

 of two tubular filaments lying close together. 



These insects undergo the most complete metamorpho- 

 sis ; first, the egg from which proceeds the well-known 

 caterpillar. Some kinds of these larvae are social, and 

 spin for themselves a common nest in which they live 

 together, until they are able to come forth and sustain 

 themselves singly. Most of them have eight pairs of 

 feet ; three pairs, the forelegs or feet, are covered with 

 a horny substance, resembling scales; four pairs, situ- 

 ated in the middle portion of the body, are membrane- 

 ous; the last pair are situated at the posterior extrem- 

 ity.f Some the Spanners or Measurers^ are without 

 the middle or membraneous feet, and walk by seizing 

 hold of the object with the six fore feet, and, elevating 

 the body into an arch, bring the hind feet close to the 

 others, and disengaging the first, repeat the maneuver ; 

 their mode of progress is too well known to require a 

 more minute description. Most of these caterpillars are 

 are of brilliant color ; some have soft naked bodies, oth- 

 ers are hairy, tubercled, or spined ; some soft and downy, 

 others coarse and bristly. Peculiar species feed on the 

 leaves of peculiar plants ; others are not particular, but 



* In the perfect insect these membraneous feet disappear, leaving 

 but six visible. 



\ Called by the Germans Nachschieber. 

 \ Geomeira or Loopers. Tr. 



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