206 POWDERED VEGETABLE DRUGS 



3. Barley starch, Gerstenstarke, G. From the grains of Hordeum 

 sativum Pres., Gramineae. The starch granules resemble those of 

 wheat excepting that they are generally somewhat smaller and some- 

 what more irregular in outline. An admixture of barley and wheat 

 starch would be difficult to detect. 



4. Corn starch, Kornstarke, G. Maisstarke, G. Fecule de mais, 

 Fr. From the kernels of Zea mays L., Gramineae. This is the official 

 starch of the U. S. P. The granules are usually polygonal, though 

 some of them are rounded or spheroidal. The hilum is distinct, 

 fissured, and the polarizing bands are very distinct. The majority 

 of the granules measure about 25ju in diameter, though some reach 

 a diameter of 30 to 35ju. They are quite uniform as to size and form. 



5. Rice starch, Reisstarke, G. Farina de riz, Fr. The starch 

 obtained from the seeds of Oryza sativa, Gramineae. 



In form and other characters much like corn starch but much 

 smaller; it is the smallest of the commercial starches; granules quite 

 uniform; many aggregated; a few compound granules. (2 to 8/*.) 



6. Potato starch, Kartoffelstarke, G. Fecule de pomme de terre, 

 Fr. From the tubers of Solanum tuberosum L., Solanaceae. 



Granules small to large; irregularly oval or pear-shaped; hilum 

 not very conspicuous, excentric, nearer the narrowed end; stratifica- 

 tion distinct. (50 to 90ju.) 



7. Maranta or Arrowroot starch, Marantastarke, G. Salep des 

 Indes occidentalis, Fr. From the rhizomes of Maranta arundinacea L., 

 Marantaceae. 



Granules resemble those of potato starch in general appearance, 

 smaller, more uniform in size and hilum at larger end instead of the 

 narrower end. (30 to 75/*). 



8 Canna starch, Toulema starch, Cannastarke, G. Amidon de 

 canne, Fecule de Tolomane, Fr. From the rhizomes of Canna 

 edulis Ker., Marantaceae. 



In form and size not unlike potato starch, more variable in outline ; 

 hilum mostly near the narrower end. (50 to 115;u.) 



9. Brazilian arrowroot, tapioca or Cassava starch, Cassavastarke, 

 G. Amidon de Cassava, Fr. From the roots of Manihot utilissima 

 Pohl, Euphorbiaceae. 



Granules of about the size of corn starch; single granules spher- 

 oidal; hilum quite distinct, somewhat radiate, centric; many granules 

 compound in twos and threes, mostly separated, showing facets. 

 (15 to 30/i.) 



10. Sago, East Indian arrowroot, Sago, Palmenstarke, G. Sagou, 

 Fr. From the pith of various palms Metroxylon Sagu Rottboell, 



