Two canals from the bottom of the internal nares, across the arch of the palate, which open behind the first and largest of the dentes incisorii; their lower orifices are in the foramen pala-rinum anterius, called nasopalatini ductus.

Incisorii inferiores Cowperi, musculi, arise from the alveoli of the lateral incisores of the lower jaw.and are inserted into the middle of the semi-orbicularis of the lower lip.

Incisorii latera'i.es, musculi. Canini minores A biceps muscle, which unites at the other extremity. It arises from the os maxillare, below the middle tendon of the orbicularis palpebrarum, and below the edge of the orbit in the os maxillare, near the union of this bone with the os malae; the heads from each side unite about the lateral dentes incisorii.

Incisorii medii, musculi; incisorii minora Cow. fieri, or incisores, minores, superiores; are two small short muscles situated near each other below the septum narium: they rise from the os maxillare, on the alveoli of the first incisores, and are inserted into the middle and upper part of the upper lip.