Structure and development of the scale case of Mallomonas adamas (Synurophyceae)

Abstract

The structure and development of the elaborate scale case of Mallomonas adamas (Synurophyceae) was studied throughout the cell cycle. Immediately following division, scale cases normally possess 30 siliceous scales, or 5 rows of 6 scales each. Scale rows overlap one another and spiral around the cell in a clockwise direction when viewed from either end of the cell. Throughout interphase, a duplicate set of 30 scales is manufactured and secreted into the existing scale case in a precise sequence, resulting in a scale case with 60 scales, or 5 rows of 12 scales each. Scales are not added to the scale case in rows, but individually positioned within the cytoplasm and inserted one at a time over..