Electron microscopic observations on avian esophageal epithelium.

The stratified squamous epithelium of the chicken and pigeon esophageal mucosa was studied mainly with the electron microscope. 1. The basal and spinous cells contained well-developed Golgi complexes, many mitochondria and multivesicular bodies. In the chicken basal cell a centriole and a single cilium were found. Both cells were rich in free ribosomes; the cisternae of the granular endoplasmic reticulum were sparse though tending to increase towards the spinous cells. The tonofilament bundles conspicuously increased towards the spinous cells. 2. In the chicken spinous cells some dilated cisternae of the granular endoplasmic