850 STARCHES OF NYMPH^ACEiE. 



than others. After heating in water until all the grains are completely gelatinized, the grains are col- 

 ored very deeply, but the solution not at all, with iodine. After boiling for 2 minutes, the grain- 

 residues are much less deeply colored and some are reduced to granular masses which do not color at 

 all ; but the solution is colored deeply. With an'excess of iodine the capsules become a blue-violet. 



Staining Reactions. — With gentian violet the reaction begins in a minute and in 30 minutes all 

 are deeply stained. Grains greatly fissured are at first stained more than the others. 



With safranin the reaction begins at once and in 30 minutes the grains are well stained, but 

 not deeply. 



Temperature Reaction. — The temperature of gelatinization is 58° to 59.5° C, mean 58.75°. 



Effects of Various Reagents. — With chloral hydrate-iodine reaction begins slightly in 30 seconds. 

 All are affected and about five-sixths are fully gelatinized in 20 minutes. The hilum often becomes 

 very prominent as a dark spot or bubble. The margin grows clearer and darker and the inner por- 

 tion light and opaque. The distal end grows dark and this coloration tends to spread all around 

 the margin. Gelatinization with swelling and protrusion of the contents of the grain begins at the 

 distal end and extends over the whole grain. In the aggregates, gelatinization begins with each com- 

 ponent grain on one side at the line of fissuring. The proximal end may become dark, but there 

 is very little gelatinization. The gelatinized grains are large, somewhat distorted, and somewhat 

 lobulated. Commonly the distal end has alternate light and dark bands, above which is a round, 

 clear space, representing the swollen hilum. 



Reaction with chromic add begins in 20 seconds and is over in 2 minutes. The hilum is promi- 

 nent, but the lamellsB not especially so. The hilum swells, and if a bubble is present it is forced to 

 one side and disappears. As the hilum swells, the whole grain is at first divided by fine radiating 

 fissures, and then swells, a thin marginal ring being formed, which is striated and banded. The 

 main mass of the substance of the grain is forced, in the form of a granular mass, to the distal end. 

 This and the margin quickly clears. The grain is much swollen, one portion of the margin at the 

 proximal end dissolves, and the granular contents are extruded and dissolved, followed by solution 

 of the remaining parts. 



The reaction with pyrogallic acid begins in 20 seconds and is over in 23^ minutes. The hilum, 

 if fissured, becomes distinct as a dark bubble. It swells rapidly, especially in the direction of the 

 proximal end. The bubble is forced to one side and disappears. There is an invagination of the 

 margin from one side so that the grain has the appearance of a large central cavity surrounded by a 

 double ring of banded, striated mass with a clear space between the two rows which represents 

 the swollen hilum. The gelatinized grain finally becomes clear and may be either round, ovoid, or 

 ring-shaped, and somewhat folded and seamed. 



The reaction with ferric chloride begins in 30 to 60 seconds and is over in 15 minutes. The 

 hilum appears as a dark bubble and the lamellse disappear. The margin becomes clear and darker 

 and the inner portion becomes light and opaque. Gelatinization begins with irregular protrusion 

 at the distal end and may progress around the margin. Usually before gelatinization has progressed 

 very far the hilum swells enormously. The thin, distinct marginal ring formed is finely striated. 

 The ring soon becomes thinner and clearer. One side of the grains invaginates. The gelatinized 

 grains are large, ovoid or round, lobulated at a distal end, and folded and seamed. 



The reaction with Purdy's solution begins immediately and is over in 30 seconds. The reaction 

 is so rapid that it is hardly possible to make out the steps. It appeared to resemble closely the 

 reaction with pyrogallic acid. 



STARCH OF NELUMBO LUTEA. (Plate 94, figs. 559 and 560. Chart 366.) 



Histological Characteristics. — In form the grains are simple. No compounds were observed. 

 There are a few aggregates which generally are in the form of doublets. A single pressure facet is 

 noted on occasional grains. There are a few clumps. The surface is quite regular, but a few irreg- 

 ular forms are seen in which a set of lamellae has its axis at an angle with that of the original set, 

 rarely as much as at right angles. The conspicuous forms are ovoid, oval, and round, with modifi- 

 cations; also dome-shaped, hemispherical, and sugar-loaf-shaped, and some irregular forms. 



The hilum is a well-defined, fairly large, slightly round refractive spot, centric in a few round 

 forms and eccentric in all other grains, usually from about two-fifths to one-third of the longitudinal 

 axis. Two hila are occasionally found in one grain. A short transverse fissure is sometimes observed 

 instead of the hilum. The fissuration is less than in N. nucifera. 



