FOUR-FOOTED BUTTERFLIES. 
279 
specimen of this fine butterfly was taken at Sandwich, by 
Mr. John Bethune. 
Some butterflies have the first pair 
of legs so much shorter than the oth- 
ers that they cannot he used in walk- 
in<\ and are folded on the breast like 
a tippet. Their caterpillars, when 
about to transform, do not make a 
loop to support the fore part of the body, but suspend them- 
selves vertically by the hindmost feet. As they all secure 
themselves pretty much in the same way, it may be proper 
to explain the process. Having finished eating, the caterpil- 
lar wanders about till it has discovered a suitable situation 
in which to pass through its transformations. This may be 
the under side of a branch or of a leaf, or any other hor- 
izontal object beneath which it can find sufficient room for 
its future operations. 
Here it spins a web or tuft of silk, fastening it securely to 
the surface beneath which it is resting, entangles the hooks 
of its hindmost feet among the threads, and then contracts 
its body and lets itself drop so as to hang suspended by the 
hind feet alone, the head and fore part of the body being 
curved upwards in the form of a hook. After some hours, 
the skin over the bent part of the body is rent, the fore part 
of the chrysalis protrudes from the fissure, and, by a wrig- 
gling kind of motion, the caterpillar-skin is slipped back- 
wards till only the extremity of the chrysalis remains attached 
to it. The chrysalis has now to release itself entirely from 
the caterpillar-skin, which is gathered in folds around its tail, 
and to make itself fast to the silken tuft by the minute hooks 
with which the hinder extremity is provided. Not having 
the assistance of a transverse loop to support its body while 
it disengages its tail, the attempt would seem perilous in the 
extreme, if not impossible. Without having witnessed the 
operation, we should suppose that the insect would inevitably 
fall, while endeavoring to accomplish its object. But, al- 
Fig 108. 
Thecla Augusta. 
