Fine Structure of a Diatom Centrosome

Abstract
The centrosome of the diatom Surirella ovalis is a dense spherical structure 500 mµ in diamneter with filaments 15 mµ in diamneter connected to it. The interior is filled with uniform granules but does not contain a typical centriole or clear area. The filaments emanating from it resemble the filaments of the mitotic apparatus, but they are present during interphase and appear to terminate at pores in the nuclear envelope.