THE ULTRASTRUCTURE OF TASTE-BUDS IN THE NEWBORN CAT

The ultrastructure of taste buds on circumvallate papillae was studied in one-day-old kittens. Attention was paid to the occurrence, localiz ation and presence of organelles in dark, light and receptor cells, fo rmation of the porus gustatorius and occurrence of intragemmal nerve f ibres and their relation to the three cell types of the bud. At the ti me after birth, the feline taste bude contained dark, light and recept or cells. All three cell types had a high amount of filaments in the c ytoplasm. In the dark cells, secretory granules and dark substance in the porus gustatorius were seen only occasionally. Both dark and light vesicles in the cytoplasm were only rare findings in the receptor cel ls. The apical portions of bud cells did not terminate as microvilli a nd never came to level with the epithelial surface. Infrequent intrage mmal nerve fibres were in contact with all bud cell types.