Morphology of the primate nasopharynx

Abstract

The morphology of the nasopharynx of tree shrew, slow loris, monkey, siamang and man has been studied by gross dissection and histological, histochemical, cinefluorographic and contrast radiographic techniques. It is clear that the primate 'nasopharynx' consists of an anterior 'nasal' and a posterior true 'pharyngeal' portion, the junction between the 2 occurring at about the level of the tubal orifices. Moreover, the 'nasal' portion appears to be a backward extension of the nasal cavity while the true 'pharyngeal' portion is an upward continuation of the oropharynx. Possible taxonomic and evolutionary implications of the findings are discussed.