The premaxilla is a pair of small bones at the very tip of the jaws of many animals, usually bearing teeth, but not always. They are connected to the maxilla and the nasals. Used to fill a man with much breath. The maxillae are the largest bones of the face, except for the mandible, and form, by their union, the whole of the upper jaw. ... The nasals are a pair of bones in the skull of many animals. ...
During the same evolutionary sequence, the premaxillae generally became the principle tooth-bearing element of the upper jaw, while the maxilla developed into a lever, structured so as to protrude the premaxilla and drop the floor of the mouth for suction feeding.
The sarcopterygian premaxilla appears to be homologous to the actinopterygian bone, although the case is not as clear as it might be.
It varies among families in the size of its two components, the palatal and nasal branches, and in whether the nasal branches are fused to each other at the midline, or whether they are fused to the adjacent maxillae.
Problem: The premaxilla (also known as the incisive bone, intermaxillary bone, or Goethe bone) is the bony segment of the maxilla that lies between the lateral borders of the lateral maxillary incisors.
The leptorrhine nose is characterized by a prominent anterior nasal spine and prognathic premaxilla.
The platyrrhine structure of the typical African nose exhibits retrusion of the premaxilla with an almost absent nasal spine.
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