Glossary
Like the rest of this website, the glossary is a work in progress. If we’ve missed a term, please contact us to let us know the term and references.
Porte-crayon
A porte-crayon is a pointed, hyaline area that surrounds the distal end of the raphe. It is formed by the joining of the longitudinal ribs that lie along each side of the raphe. Porte-crayons are found in the genera Frustulia and Amphipleura. In French, porte-crayon means pencil holder.