Percipient: with the power of perceiving.
Percurrent: running through the entire length.
Pereion: the prothorax.
Pereipoda: the second and third pair of thoracic legs of larvae, and the 2d pair in adults.
Perfoliate: divided into leaf-like plates: applied to antennae with disc-like expansions connected by a stalk passing nearly through their centres: also to any part possessing a well-developed leaf-like or plate-like expansion.
Pergamenous: thin, partly transparent: resembling parchment.
Peri-: round about. Periopticon: a complex nerve structure back of the basilar membrane of the eye.
Pericardial: around, or belonging to the heart.
Pericardial cavity: the space between the diaphragm and dorsal body wall, which contains the heart.
Pericardial cells: specialized cells, which lie along both sides of the heart, and whose function it is to purify the blood.