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Genus HIPPARCHIA. 
With the exception of Polyommatus, which ap- 
proaches it in the number of species, this is by far 
the most extensive genus among the British Butter- 
flies. As at present constituted, however, it is not 
of a very homogeneous nature, several of the insects 
which it includes not only differing considerably from 
each other in habit, but also in the form of tha 
wings, the proportions of the joints of the palpi, and 
other essential parts of structure. None of the in- 
digenous kinds are remarkable for the brightness of 
their colours, the prevailing tints being deep brown, 
relieved and variegated with oclire-yellow and brown- 
ish-red •, and the under side is often ornamented with 
eye-like spots. The caterpillars are almost inva- 
riably of some shade of green, and are thus assimi- 
lated, no doubt with a view to their safety, to the 
colour of the plants on which they feed, viz. the dif- 
ferent kinds of grasses. Their bodies are nearly 
naked, or covered only with short hairs, and there 
are two projecting points behind, which make the 
anal extremity appear bifid. The antenna; are va- 
riable in length, the club generally spindle-shaped, 
or tapering at both ends, and curved ; in H. semele, 
