120 STARCH ITS FORMS. [BOOK i. 



sulphuric acid. Found exclusively in Gingerworts (Zin- 

 giberacese) in the rhizomes ; not in Marants. 



IV. Club-shaped Granules. 



13. With long central holes,, in the milky sap of European 

 and some tropical Spurgeworts (Euphorbiacese.) 



V. Perfectly irregular Grains. 



14. In the milky juice of most tropical Spurgeworts. 



III. COMPOUND GRAINS. Single grains are only found as 

 exceptions in this group. 



I. Single united Grains without an apparent central hole. 



15. Two, three, or four simple grains are united in the 

 rhizome of Maranta (West-Indian Arrowroot), in the 

 tubercles of Aponogeton, in the thickened disjointed 

 parts of the leaves of Marattia, and in the root of Bryonia. 



16. From 2 6 grains, usually united regularly, seldom 

 irregularly, in the bark of the roots of all sorts of 

 Sarsaparilla. 



II. Single united Grains with an apparent central hole. 



A. All parts of the grains of nearly the same size. 



17. From 2 4 simple grains united, the central hole being 

 small and round. As in the tubercles of Manihot. 



18. From 2 4 simple grains united, the central hole being 

 large and mostly torn in a stellate manner. As in the 

 corm of Colchicum autumnale. 



19. From 2 4 simple grains united, each grain being 

 hollow and apparently cup-shaped. This remarkable 

 form occurs in the Grass oil plant : Radix Iwarancusa? 

 (Anatherum Iwarancusse.) 



20. From 2 12 grains firmly united in very irregular 

 masses. In the rhizome of Arum macula turn. 



21. A great number (often as many as 30) small round 

 grains joined so as to form loose spherical masses. 

 Frequent in the stem of Bernhardia dichotoma. 



