Abstract.Hyaline bodies in odontogenic cysts were studied in the electron microscope after retrieval from paraffin blocks. Although epithelial preservation was poor, hyaline bodies appeared to be well preserved. Our observations do not support unequivocally either of the two major hypotheses of pathogenesis ‐ epithelial cell production or hematogenous origin. Electron micrographs do, however, clearly demonstrate that hyaline bodies are not composed of keratin. Hyaline bodies in our material reveal no ultrastructural similarity to the published electron micrographs of cuticle “B” which Listgarten (1966a, b) suggested corresponds to the secondary enamel cu