6G DIFFERENTIATION AND SPECIFICITY OF STARCHES. 



III. Compound Granules. Here we find a simple grain as an exception in the plant or part of the 

 plant. 



1. The separate grains in the compound grains without evident central cavity or hilum. 



15. Compounded according to the simplest types in 2, 3, or 4, as in the rhizomes 



of Marantacew (West Indian arrowroot). Also in tu])crs oi Aponogdon, in 

 the thickened vagination of the leaves of Marattia, and in roots of Bryonia. 



16. Gcnerallj' arranged regularly, seldom irregularly, and composed of from 2 to 6. 



In the bark of the roots of the various sorts of sarsaparilla. 



2. The separate grains in the compound grain having a distinct central cavity or hilum. 



(a) All the parts of the grains of nearly the same size. 



17. United according to simple types from 2 to 4. The central cavity or hilum 



small and roundish, as in the tubers of Jatropha manihot. 



18. Combined according to simple types from 2 to 4. The central cavitj^ or hilum 



large and very beautiful, opened in a star-like form, as in the corms of 

 Colchicum aidumnale. 



19. Combined according to simple iypcs from 2 to 4. The separate grains quite 



hollow, apparently cup-shaped. A marked form occurs in Radix ivarancusa; 

 (Anatherum ivarancusa:). 



20. Firmly combined, from 2 to 12 in number, in verj- irregular groups, as in the 



rhizomes of Arum maculatum. 



21. A large number, often as many as 30, of small rountlish grains, very loosely 



gi'ouped. Frequent, for instance in the stem of the Bcrnhardia dichotoma. 

 (6) Many smaller grains grown together upon one larger one. 



22. In the pith of Sagua rumphii, etc., and generally in sago. 



Nageli's Classification of Starches from Different Sources. 



A. Grains Simple. 



I. Centric. Hilum in the mathematical center; lamellse always equal at two corresponding 



diametrically opposite points. 

 Type 1. Spherical. When the grain is free both hilum and grain are spherical. 

 Type 2. Lenticular. When the grain is free both hilum and grain are rounded; grains 



compressed; sometimes circular or ovoid; sometimes triangular or quadrangular. 

 Type 3. Oval. When the grain is free both hilum and grain are oval to lanccoIate-o\'al; 



occasionally kidney-shaped or somewhat curved; when on end they appear circular 



or somewhat compressed. 

 Type 4- Spindle-shaped. Grain linear or lanceolate, tapering towards the pointed ends, 



or of equal width "with l)hmt ends; when on end they appear almost circular. 

 Type 5. Bone-shaped. Grain elongated and compressed from the narrow aspect, but 



linear spindle-shaped from the broad aspect, with enlarged laminated ends. 



II. Eccentric. Hilum usually more or less removed from the mathematical center of the grain; 



lamellse 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. 

 Type 7. Cone-shaped. Grains on end almost circular; decidedly thicker and broader at 



the hilum end. 

 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. 

 Type 9. Rod-shaped. 



III . Grains simple and structure obscure. 



Type 10. Structure not fidly developed, or not identified oiving to diminutive size of the grains. 

 Lamellse, hila, cavities, fissures, and clefts seldom observed. 



B. Grains semi-compound. 



Type 11. Grains semi-compound. The component part-grains are enveloped partly or 

 wholly by a common substance. 



