On the avian Merkel cells.

Small Merkel cells are described in the hard palate epithelium of the chick. Further, spherical juxtaepithelial Merkel cells and more deeply situated apparently degenerating Merkel corpuscles are also described. The observations are interpreted as a reflection of a sequence of growth and decay of Merkel corpuscles, and seem to support the hypothesis of an epithelial origin of the Merkel cells.