The mandibles have no Palpi, the maxillipeds or foot-jaws are used as feet, whereas in the mature form they serve as jaws.
"On the Origin and Metamorphoses of Insects"
Sir John Lubbock
A tiny ball of earth is held between the fangs and is supported by the Palpi, or feelers, which are little arms employed in the service of the mouth-parts.
"The Life of the Spider"
J. Henri Fabre
Like the others, these hasten to the red- woollen lure, which my straw insidiously keeps moving; they come from their tent among the leaves as readily as from the centre of the web; they explore it with their Palpi and their legs; but, soon perceiving that the thing is valueless, they are careful not to spend their silk on useless bonds.
"The Life of the Spider"
J. Henri Fabre