| | 0.00022 | small size the only | | | points. | | | Podophyllum |Like tapioca |About 0.00040|Like scammony, but has | | | visible hilum in most | | | of the granules. | | | Aconite | do. | ” 0.00037|Like tapioca, but half | | | the size. -------------+--------------+-------------+------------------------ _Group V_: All granules more or less polygonal. -------------+--------------+-------------+------------------------- Name. | Shape. | Normal | Remarks. | |measurements.| -------------+--------------+-------------+------------------------- Tacca |Poly- or | 0.00075 |Distinguished from maize | hexagonal | to 0.00037 | by its sharp angles. | | | Oat |Polygonal |About 0.00037|Larger than rice and | | | hilum visible in some | | | granules. | | | Rice | do. | 0.00030- |Measurement using | | 0.00020 | one-eighth or | | | one-twelfth inch power, | | | and then hilum visible. | | | Pepper | do. | 0.00020- | Do. | | 0.00002 | Ipecacuanha | do. |About 0.00018|Some round and truncated | | | granules, adhering in | | | groups of three. -------------+--------------+-------------+------------------------- =199. Blyth’s Classification.=—Blyth gives the following scheme for the identification of starch granules by their microscopic appearance.[165] _Division I.—Starches showing a play of colors with polarized light and selenite plate_: The hilum and concentric rings are clearly visible, and all the starch granules, oval or ovate. Canna arrowroot, potato, arrowroot, calumba, orris root, ginger, galangal and turmeric belong to this division. _Division II.—Starches showing no iridescence, or scarcely any, when examined by polarized light and selenite_: Class I.—The concentric rings are all but invisible, and the hilum stellate. The bean, pea, maize, lentil, dari and nutmeg starches are in this class. Class II.—Starches which have both the concentric rings and hilum invisible in the majority of granules: this important class includes wheat, barley, rye, chestnut, acorn, and many starches in medicinal plants.