[Fig. 20] is nearly circular or rounded polyhedral in forms with scarcely visible rings, and in most cases a depressed hilum, resembling in size and shape corn starch, but having peculiar irregularities which distinguish it, such as rosette-like formation on a flattened granule, or a round depression at one end. It does not polarize as actively as maize starch and can be distinguished from rice by the greater angularity of the latter.
PEPPER STARCH
[Fig. 21] is the most minute starch which is usually met with, not averaging over .001 millimeter nor exceeding .005. It is irregularly polyhedral and polarizes very well, but requires a high power to discover any detail when a hilum is found. It cannot be confused with other starches.
CINNAMON STARCH
[Figs. 22] and [23] have an extremely irregular polyhedral or distorted granules, often united in groups with smaller granules and adherent to the larger ones. In size, it varies from .001 to .025 millimeter, averaging nearly the latter size. In some granules the hilum can be distinguished, but no rings; it is readily detected with polarized light.
BUCKWHEAT STARCH
[Fig. 24] is very characteristic. It consists of a chain or groups of angular granules with a not very evident circular nucleus and without rings. The outline is strikingly angular and the size not very variable, being about .01 to .015 millimeter.
MAIZE OR CORN STARCH
[Figs. 25] and [26] have granules largely of the same size from .02 to .03 millimeter in diameter, with now and then a few which are much smaller; they are mostly circular in shape or, rather, polyhedral with rounded angles. They form very brilliant objects with polarized light, but with ordinary illumination show but the faintest signs of rings and a well-developed hilum, at times star-shaped and at others more like a circular depression.