DERMAL PAPILLA AND THE DEVELOPMENT AND GROWTH OF HAIR 755 DISCUSSION PROF. F. J. G. EBLING: One aspect of your work which particularly intrigued me was your suggestion that oral epithelium, under the influence of dermal papilla, cannot quite decide whether to form a tooth-like or a hair-like structure. Could you expand this? THE LECTURER: Oral epithelium seemed to respond in two quite different ways under the influence of dermal papillae. Sometimes, and perhaps here understandably, it developed into recognisable hair follicle elements. However, at other times it closely resembled, particularly in its stellate reticulum-like configuration, enamel organ of early developing teeth. MRS. H. BUTLER: Did this phenomenon occur in lip as well as in gum epithelium? THE LECTURER: Yes. More hair follicles developed in lip epithelium than gum and stellate reticulum-like configurations in epithelia from both sites. DR. I. M. GInSON: Have you tried to develop hair follicles in the normally hairless epidermis of the rat foot pad? THE LECTURER: No, but Kollar (16) has induced follicle development in embryonic mouse foot pad epidermis. MR. K. M. GODFREY: Did you go far enough to allow the hair to grow and penetrate the epidermis? THE LECTURER: Yes. Hair follicles induced from ear epidermis grew hair above the ear surface.