The larvae ( caterpillars ) of a few of these species , such as `` Pieris brassicae '' and `` Pieris rapae '' , commonly seen in gardens , feed on brassicas , and are notorious agricultural pests .
The caterpillars of a few of these species , such as `` Pieris brassicae '' and `` Pieris rapae '' , feed on brassicas . They are commonly seen in gardens and are agricultural pests .