The Innervation of the Periodontal Membrane of the Cat, with some Observations on the Function of the End-Organs found in that Structure.

IN a recent paper, the authors gave an account of an investigation which they had made into the innervation of the periodontal membrane in man. They were able to show that the nerve fibres in this tissue broke up into arborizations, many of which ended in round knob-like bodies (4). The results obtained were similar to those which have been described by Kadanoff(3), who also used human material, and were not unlike the findings of Bradlaw (1) who based his conclusions on the periodontal membrane of the monkey. They, however, differed markedly from the findings of van der Sprenkel (5) who, in his examination of the periodontal membrane of the young mouse, had seen an entirely different type of nerve ending. The authors put forward the suggestion in this paper that the discrepancies in van der Sprenkel's results which differed so markedly from those of all other investigators in this field, might be due to the different material which he employed. present investigators study, and they have therefore widened field their investigation studying some typical examples of more mammalian genera. are such interest as deserve further communication this subject before the the work