A hole in the diatom (with a number of possible structures), often arranged into stria.

Pore or perforation through the valve, an areolae is a puncta bounded by an internal or external sieve membrane

General term for pore/perforation through valve when substructure (i.e. sieve membrane) is unknown or lacking. Often arranged into stria.

(singular: punctum) openings located at the nasal margins of the upper and lower eyelids through which tears enter the lacrimal drainage system.

A channel in the inner corner of the eye through which tears drain into the back of the throat.

External orifices of the upper and lower canaliculi.