| Abstract: The ultrastructure of jaws in three species of the genus Glycera (Errantia, Glyceridae) has been investigated. Two of these are the Jurassic G. baltica and G. pilicae, another, the Glycera sp. is a Recent one. G. baltica differs from the other species by a lack of protein fibrils. The channels in the matrix were interpreted as traces of fibrils left after the breakdown of collagen. The fibrils have been interpreted as the material filling the channels left after the breakdown of collagen. The fibrils in Glycera have been compared with the fibrils and channels in the jaws of Halla parthenopeia (Eunicidae) and Nephtys sp. (Nephtyidae). Structures observed in the myocele of G. baltica may be the vestiges of collagen cuticle underlying the jaws. |
