Response of the avian chorionic epithelium to presumptive scale‐forming dermis

Abstract

Abstract The isolated chorionic epithelium (CE) from 8‐day chick embryos responds to the inductive influence of anterior shank (scale) dermis (ASD) in different ways depending on the age of the dermis. Eleven‐day dermis induces the fomrmation of barb‐ridges, typical of feathers, yet, very little feather elongation; while 13‐day dermis induces the CE to form normal scale epidermis. Twelve‐day ASD elicits both the formation of barb‐ridges and scales. Thus, the ASD, in association with the overlying scale‐forming epidermis, becomes altered in its inductive ability between 11 and 12 days of development.