Scanning electron microscopic investigations of olfactory epithelium in the chick embryo.

This paper describes maturation of the surface of the olfactory epithelium of the superior nasal concha of chick embryos from the seventh day of incubation till hatching. From the earliest stages investigated onward, the apical surface of the olfactory epithelium is characterized by variability in the number and configuration of surface protrusions. The growth of olfactory cilia is described and the significance of regional differences in their density is discussed in relation to regional variations in the sensitivity of the epithelium to odorants. The maturation of the respiratory epithelium covering the inferior nasal concha is also described.