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and rudimentary, feed mostly on the leaves of shrubs and 
trees ; their moths are of large size, with the hind wings 
often crimson, scarlet, or yellow, and traversed by black 
bands. But as these insects are not particularly interesting 
to the farmer, any further account of them, in this treatise, 
will be unnecessary. 
3. Geometers. (Geometry.) 
The caterpillars of the Geometry of Linnaeus, earth- 
measurers, as the term implies, or geometers, span-worms, 
and loopers, have received these several names from their 
peculiar manner of moving, in which they seem to measure 
or span over the ground, step by step, as they proceed. 
Most of these caterpillars have only ten legs ; namely, six, 
which are jointed and tapering, under the fore part of the 
body, and four fleshy prop-legs, at the hinder extremity ; the 
three intermediate pairs of prop-legs being wanting. Con- 
sequently, in creeping, they arch up the back while they 
bring forward the hinder part of the body, and then, resting 
on their hind legs, stretch out to their full length, in a 
straight line, before taking another step with their hind legs. 
Some of the Geometers have twelve or fourteen legs; but 
the additional prop-legs arc so short that the caterpillars 
cannot use them in creeping, and their motions are the 
same as those that have only ten legs. Some caterpillars 
with fourteen legs, and wanting only the terminal pair of 
prop-legs, are placed in this tribe, on account of the resem- 
blance of their moths to those of the true Geometers. 
The latter live on trees and hushes, and most of them 
undergo their transformations upon or in the ground, to 
reach which, by travelling along the branches and down 
the stem, would be a long and tedious journey to them, 
on account of the deficiency of their legs, and the slowness 
of their gait. But they are not reduced to this necessity; 
for they have the power of letting themselves down from 
