Head: Left lateral view - Chicken CC: Comb (Crista carnosa): BL= Blade; P= Point; BD= Body; BS= Base; NE: Nares externus; ON: Operculum nasalis; MX: Maxillary rhamphotheca; MR: Mandibular rhamphotheca; PCL: Wattles (Palea carnosa laryngis); PD: Palpebra dorsalia; PV: Palpebra ventralia; PU: Pupil; IR: Iris; PA: External ear opening (Porus acusticus externus); LA: Lobus auricularis;