Nägeli's (1874) Classification of Starches From Different Sources
A. Grains Simple.
I. Centric. Hilum in the mathematical center; lamellae always equal at two corresponding diametrically opposite points.
Type 1. Spherical. When the grain is free both hilum and grain are spherical (Plate 1, Zea mays).
Type 2. Lenticular. When the grain is free both hilum and grain are rounded; grains compressed; sometimes circular or ovoid; sometimes triangular or quadrangular (Plate 2, Secale).
Type 3. Oval. When the grain is free both hilum and grain are oval to lanceolate-oval; occasionally kidney-shaped or somewhat curved; when on end they appear circular or somewhat compressed (Plate 6, Phaseolus and Doliches).
Type 4. Spindle-shaped. Grain linear or lanceolate, tapering towards the pointed ends, or of equal width with blunt ends; when on end they appear almost circular (Euphorbia, none illustrated).
Type 5. Bone-shaped. Grain elongated and compressed from the narrow aspect, but linear spindle-shaped from the broad aspect, with enlarged laminated ends (Euphorbia, none illustrated).
II. Eccentric. Hilum usually more or less removed from the mathematical center of the grain; lamellae coarsest and finest at opposite ends of the grain, respectively.
Type 6. Inverted cone-shaped. Grain on end almost circular; slender at the hilum end (Plate 100, Solanum tuberosum).
Type 7. Cone-shaped. Grains on end almost circular; decidedly thicker and broader at the hilum end (Plate 35, Scilla peruviana).
Type 8. Wedge-shaped or compressed. Grains flattened, of equal thickness throughout, or thicker but narrower at the hilum end than at the distal end (Plate 83, Canna edulis).
Type 9. Rod-shaped (Plate 63, Iris florentina, I. pallida).
III. Grains simple and structure obscure.
Type 10. Structure not fully developed, or not identified owing to diminutive size of the grains. Lamellae, hila, cavities, fissures, and clefts seldom observed (Plate 60, Narcissus poeticus).
B. Grains semi-compound.
Type 11. Grains semi-compound. The component part-grains are enveloped partly or wholly by a common substance (Plate 41, Hyacinthus orientalis).
C. Grains Compound. The component part-grains not enveloped by a common substance.
I. Composed of fused part-grains.
Type 12. Composed of fused part-grains. The part-grains are not separated by fissures, and even different grains may be fused with one another (Plate 80, Zingiber officinale).
II. Composed of separated part-grains. The part-grains separated by fissures.
Type 13. Grains in I or 2 rows. From 3 to 11 components arranged in I or 2 rows (Plate 10, Polygonum fagopyrum).
Type 14. Equally divided grains of few components. From 2 to 10 or more almost equal-size part-grains which when separated have I curved surface and 1 or more pressure facets (Plate 98, Manihot and Plate 100, Batatas edulis).
Type 15. Unequally divided grains of few components. From 2 to 10 or more unequal sized firmly united part-grains, which when separated have 1 curved surface and several flattened pressure facets (Plate 95, Aconitum napellus).
Type 16. Multiple grains. From 20 to many thousand firmly united part-grains which when separated are covered with pressure facets (Plate 2, Oryza sativa).
Type 17. Hollow spherical grains. The part-grains are arranged in a spherical layer, as if a globular shell had been divided radially (Algae, none illustrated).
