Charles Darwin,
A Monograph on the Sub-class Cirripedia…
“ There is here no distinction between a peduncle and capitulum, that is between the lower or anterior, and the upper or posterior end of the animal, as seen externally. The small orifice is toothed and hairy: it is coloured purple, as is likewise the projecting labrum; the rest of the animal being tinted only by the muscles and internal parts seen through the outer integuments. ”
