Apical axis

Annulae

 

Apiculate

The long axis of the valve face of a pennate diatom, passing through the apices. Follows the midline of the valve and may be curved, as in the genus Cymbella. See Pervalvar axis and Transapical axis.


Citations

Round, F.E., Crawford, R.M. and Mann, D.G. (1990). The Diatoms. Biology and Morphology of the Genera. Cambridge University Press, Cambridge, 747 pp.