656 STARCHES OF LILIACE^. 



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

 and is over in 8 minutes. The reaction begins at the distal end of the grain, which becomes dark 

 violet, and this color spreads over the entire surface of the grain. The distal end soon changes 

 in color to a very dark indigo and swells somewhat. This process extends upward around the margin 

 and to the interior of the grain, until the whole grain is involved. The gelatinized grains so formed 

 are fairly large, uniformly dark, and retain some of the original form. 



Reaction with chromic add begins in a very few seconds and is over in 45 seconds. The hilum 

 swells, and a large bubble is formed which increases to a large size, then decreases and disappears. 

 The inner portion of the grain is changed into a gelatinous mass, and the more resistant outer por- 

 tion is formed into a thin, transparent envelope which as the grain swells becomes invaginated 

 just over the point originally occupied by the hilum. The thin wall is dissolved at some point, 

 and the inner gelatinous starch flows out and is dissolved. The capsule is dissolved, but not so 

 rapidly as the extended gelatinous mass. 



The reaction with pyrogallic acid begins in 15 seconds. The grains are nearly completely 

 gelatinized in 8 minutes and all are fully disorganized in 30 minutes. The reaction begins at the 

 hilum, which swells; the less resistant starch is changed into a gelatinous mass, the more resistant 

 collects at the margin in the form of a broad, dense band, which sometimes is seen to be finely 

 striated and which generally shows two or three indistinct, alternate, refractive and non-refractive 

 rings; usually this band slowly becomes thinner and somewhat transparent, but in many grains it 

 remains broad. The gelatinized grains are fairly large, generally smooth, and not much distorted. 



With ferric chloride the reaction begins in some grains in 45 seconds and is over in 11 minutes. 

 The reaction originates at the distal end, which is fissured internally, and from this fissure the 

 gelatinized starch protrudes as a gelatinous mass covered by a gelatinized capsule. This process 

 proceeds rather slowly towards the hilum, and when this point is reached an internal fissure extends 

 downward to the gelatinized portion. The ungelatinized part of the grain is divided into two parts 

 and these two into several pieces, which become widely separated by gelatinized starch, and then 

 gelatinize themselves independently of one another. The gelatinized grains are very large, thin- 

 walled, and irregular. 



The reaction with Purdy's solution begins in 45 and is over in 60 seconds. It appears the same 

 quahtatively as that with pyrogallic acid, but there is invagination of the capsules over the point 

 formerly occupied by the hilum. The capsules are large, wrinkled, and sacculated at the distal end. 



STARCH OF ORNITHOGALUM UMBELLATUM. (Plate 38, figs. 223 and 224. Chart 150.) 



Histological Characteristics. — In form the grains are simple and with the exception of a few 

 doublets and clumps they are isolated. No pressure facets were observed. The surface is rather 

 irregular and somewhat varied, owing in part to a set of two or three lamellae at or near the distal 

 end, whose longitudinal axis does not agree with that of the larger part of the grain; and in part 

 to irregularities in the development of the surface giving rise to small depressions in the margin, 

 chiefly near the distal end. The conspicuous form is the ovoid with a squared end, and having 

 in the center of this squared portion a deep but narrow depression; there are also spherical, irreg- 

 ularly elliptical, quadrangular with a rounded proximal end, a few triangular, and some irregular 

 forms. The grains are not flattened and are of the same thickness as breadth, hence spherical 

 when seen on end. The grains are slightly more irregular than those of 0. nutans. 



The hilum is a fairly distinct, small, round, or rarely lenticular spot. It is eccentric about 

 one-third of the longitudinal axis and in the median line. Rarely it is centric. There are occasion- 

 ally 2, and sometimes more, hila in a single grain. The hilum is often fissured, and there may be 

 a narrow, short, straight, single, clean-cut, transverse or longitudinal fissure; less often there are 

 two short, narrow, clean-cut fissures forming a cross. 



The lamellae are distinct, rather coarse, somewhat irregular, usually continuous rings; near the 

 distal end they are probably discontinuous, and also more irregular, coarser, and more distinct 

 than those near the hilum, often showing irregularities corresponding to depressions of the margin. 

 They vary in distinctness and size in different grains. There are 8 to 14 on the larger grains. 



The grains vary in size from 5 to 40/i. The common size is 21/j. 



Polariscopic Properties. — The figure is eccentric, distinct, somewhat clear-cut, and fairly regular. 

 Its lines are thick and become thicker and less well defined near the margin. They are usually 

 not bent, are sometimes placed at equal distances from one another, and may be bisected. 



