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laxed or hindered, from excessively hot or dry 
weather, which apparently render their food un- 
palatable, in what way I am not able to judge. 
It is, however, certain, that wet or showery wea- 
ther is far most conducive to their progress. The 
late dry summers serve to corroborate this, as we 
find gardens in general have been pretty free 
of this ravenous animal. 
When they are full grown they are about 
an inch in length, of a dark green, thickly 
marked with black tubercles or prominent 
spots, in some of which are inserted two or three 
hairs, others having only one, which is scarcely 
discernible without the aid of a microscope. 
They have sixteen feet, exclusive of the three 
thoractic pairs. In about six weeks after their 
first appearance, or at the fore end of June, they 
undergo their first change, by retiring under the 
leaves of the tree, and under the leaves of weeds, 
where they slough or cast their maculated skin, 
after which they are of a pale yellow colour, blend- 
ed with green. In a short time they conceal them- 
selves about two or three inches in the earth, 
where they form to themselves a cocoon or case. It 
is in texture similar to thin writing paper, is of a 
brownish colour, composed of a slimy matter, pro- 
duced from themselves, and, coated over with 
earth, forms a complete protection. The shell is 
of an oval shape, about the thickness of the first 
quill of a Goose, and about three-eighths of an 
inch in length, and the outside being incrusted 
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