Visit us at

Diatoms of the United States is now known as Diatoms of North America.
This site has been redesigned and updated, and will be closing soon.

Glossary terms starting with "g"

Ghost striae

Faint striae, composed of areolae that may not penetrate the valve wall.



Convex, rounded, protuberant; exceeding a semi-circle but less than a circle.

Girdle view

The view of the frustule when the girdle is uppermost. See valve view for an alternate view of the frustule and cingulum for a definition of the girdle.



A small rounded projection of silica on the outer surface of the valve.