224 DIFFERENTIATION AND SPECIFICITY OF STARCHES. 



into a rather elongated blunt point; strongly compressed to about one-fourth of their width; 

 lamelhT" none, or numerous and delicate; occasionally a small trausverse fissure in the hilum; 

 hilum about one-seventeenth eccentric. The grains are as large as, and occasionally larger 

 than, those of potato starch. According to Soubciran, width 20/i, length 60 to 70/i, and 

 thickness IOm. 

 Starch-grains of Tikhur-Mehl flour are about 72/n long and 38m broad, thus they are 1 to 3 times 

 as long as broad; 6 to Syu thick; sometimes from the broad aspect they are oblique or irregular, 

 and broadened toward the distal rounded end : while at the proximal end they are usually 

 narrow and triangular; this end maj' occasionally be either almost blunt or the angle may 

 protrude; even the place where the hilum is located may occasionally be more prominent 

 and wart-shaped; in the long, narrow aspect the grains are rod-shaped, and of either almost 

 equal thickness throughout or slightly thicker in the middle, with rounded or blunt ends; the 

 hilum is rarely indicated by a small cavity about one twenty-fourth eccentric; lamellae deli- 

 cate and numerous. 



Curcuma longa Linn. (Zingiberacece.) — According to Munter, grains as in preceding. 



Curcuma angustifolia Roxb. (Zingiberacece.) Root-stocks. — According to Leon Soubeiran (Joum. 

 Pharm., 18-54, xxv, 178), the grains are triangular, v.ith rather blinit, not flattened, angles; 

 lamella and hilum visible, but indistinct, grains very unequal in size, from 5 to 30^, small 

 ones numerous, many split and torn. Soubeiran concludes from this that Travancora starch 

 can not be derived from Curcuma angustifolia. 



Hedychium flavescens Carey. {Zingiberacece.) Root-stocks. — According to Fritzsche (Poggendorff's 

 Annal., 1834, xxxii, 142, taf. ii, 40-49), the grains are oval to lanceolate, narrow at the 

 hilum end, or drawn out to a point; one-third to one-half as long as broad; very strongly 

 compressed; lamellae numerous, dehcate; hilmn invisible. Also semi-compound grains are 

 present, with 2 to 4 part-grains, wliich at the hilum end are completely separated bj' fissm-es, 

 but at the distal end are surrounded with the common lamellae of the grain. 



Maranta arundinacca Linn. {Jamaica West Indian arrowroot, partly East Indian arrowroot; Mar- 

 anta starch.) {Marantacece.) Dry stolon. — Grains rounded to oval, rarely oblong, usually 

 more or less irregular; often triangular; two-fifths to twice as broad as long; the oblong and 

 oval grains are about circular in transverse section; many are pressed in until they are about 

 one-half as thick as broad; thicker at the hilum end; from the broad aspect the distal end is 

 either narrower or broader than the hilum end (to about twee as broad as the length of the 

 entire grain), the distal end is always thin; lamellae delicate; instead of the hilum a small 

 cavity is frequently found, either with a rather delicate, short, transverse fissure, or 

 with 3 to 4 short radial fissures, or rarely with a longitudinal slit; eccentricity one-half 

 to one-si.xth. Length 40 to 50yu, width about 40^. According to Soubeiran, the length is 

 60 to 70/i. Occasionally a smaller part-grain rests upon a grain, as if the grain had been 

 cut off at one corner. 



Jamaica arroicroot sp. — Related to the foregoing starch is a specimen which was sent to Niigeli 

 from England as a variety of potato starch, but which, however, was found to be a kind of 

 Jamaica arrowTOot. The grains are oval, elongated-conical, triangular to quadrangular, 

 usually more or less irregular; two-fifths to twice as long as broad; the hilum end thickened, 

 the distal end broadened; compressed, and almost obliquely angular; lamellae quite distinct; 

 delicate, the outer ones frequently forming a special lateral group; the grain is usually solid, 

 instead of the hilum there is occasionally observed either a short longitudinal or transverse 

 slit or very short radial fissures, which form a triangle, or an oblique-angled cross or more 

 rarely a right-angled cross; eccentricity about one-fifth. Length about 50^- This starch in 

 some respects acts like potato starch, or as a variety derived from it, swelling up and passing 

 into solution when cooked, dissolving if subjected to moist heat, and soluble when treated 

 with saliva. Maranta starch is easily distinguished, however, from ]iotato starch, with 

 which it is often adulterated, by means of the smaller, often obliquely triangular grains 

 (scarcely two-thirds as large as potato starch-grains) ; by the many wedge-shaped, compressed 

 forms with thickened hilum end and thinned angvilar distal margin (in the potato starch the 

 hilum is usually found at the thinner end); by the more delicate, less distinct, narrower 

 lamellae and the short slits or radial fissures which develop when the grain is dry (of which, 

 as a rule, the potato starch shows no indication). 



