RHOPALOCERA. 
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RHOPALOCERA. — Butterflies. 
Day flying insects, the antennce knobbed at the tip. No frenulum, 
the costal nervure arched at the base. 
The butterflies are familiar to everyone from their large size, their 
bright colours, their sunshine-loving habits. Whilst most are clearly 
distinct from the moths, these distinctions are not easily defined, and the 
fundamental distinction lies in the wings. In Rhopalocera, the hindwing 
has a projecting shoulder at the base, which fits under the forewing, thereby 
securing the rigidity of both wings together. This fact can be 
expressed by saying that the costal nervure is arched, as it is to support this 
shoulder. In Heterocera, the wings are held together by the frenulum, 
a bristle or tuft which projects forward from the hindwing and fits into 
a pocket on the under surface of the forewing, or the jugum, a projection 
from the posterior edge of the fore wing. The costal vein is not arched 
and moths are said to be frenulate or jugate. The distinction between 
moths and butterflies is a useful one but hardly an accurate one and 
there is little need to discuss its value. 
The butterflies are eminently a group that love the densely forested 
hills where vegetation is abundant and varied, where rain falls abundantly, 
producing a continual greenness. Few are found in the dry cultivated 
plains, where foodplants are scarce, where there are long periods of drought 
and little shelter. Those that are of wide distribution are grass-feeding 
species, species that have widely scattered foodplants among the wild 
shrubs or flowering plants, or which feed on a cultivated plant. The 
ideal place for butterflies is the lower slopes of the hills well clothed with 
forest, with a sub-tropical climate and an elevation not over three to 
four thousand feet. Here butterflies attain their greatest development 
and few places are richer than such localities in India. Fortunately 
these insects may be omitted in this place. Our concern is only with 
the few very common ones likely to be found generally distributed 
over the plains and which are abundant in the bare cultivated areas. 
Almost all butterflies have a similar life-history. The eggs are laid 
on the foodplant, singly or in clusters. The larvae have five pairs of 
suckerfeet, and feed openly on the leaf on plant tissue. Pupation takes 
place on the plant, openly, with no cocoon. The eggs are rounded, up¬ 
right, with the micropyle at the top as in the greater number of the moths. 
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