552 STARCHES OF LILIACE^. 



The degree of polarization is fairly high, varying in different grains, being low in some, high 

 in others. It varies also in different aspects of the same grain, being highest when the grain is viewed 

 on end or edge and commonly lower at margin of the distal end than near the hilum in the same 

 aspect of a given grain. 



With sclenite the quadrants are fairly well defined, generally somewhat irregular in shape, 

 and unequal in size. The colors are usually pure. 



Iodine Reactions. With 0.25 per cent Lugol's solution the grains color a deep blue-violet; with 

 0.125 per cent solution they color fairly and the color deepens rapidly. After heating in water until 

 all the grains are completely gelatinized, the solution colors lightly and the swollen grains very deeply 

 on addition of iodine. After boiling for 2 minutes the solution colors tlccplj' and the grain-residues 

 lightly or not at all. The capsules color a reddish-violet on the addition of an excess of iodine. 



Staining Reactions. With gentian violet and with safranin the grains begin to stain very lightly 

 at once and in 30 minutes are lightly colored. 



Te^nperature Reaction. The temperature of gelatinization is 55.8 to 56.9 C, mean 56.35. 



Effects of Vario^is Reagents. With chloral hydrate-iodine reaction begins in 30 seconds and is over 

 in 10 minutes. The reaction starts at the distal end with darkening and considerable irregular pro- 

 trusion, and the process advances until the whole grain is involved. There is always a sharp line of 

 demarcation between the gelatinized and non-gelatinized parts of the grain. The gelatinized grains 

 are fairly large, of a uniform dark color, and do not retain much of the original form of the grain. 



Reaction with chromic acid begins in a few seconds and is over in a minute. The reaction starts 

 at the hilum, where a bubble of gas or air forms, which increases and then decreases in size as the 

 grain swells, and finally disappears. Meanwhile fine striae appear radiating from the hilum in all 

 directions, and the less resistant starch is rapidly gelatinized, accompanied by swelling of the whole 

 grain. The more resistant starch forms a striated band at the margin which rapidly becomes thin 

 and transparent, forming finally a capsule which dissolves at the proximal end, thus allowing the 

 gelatinous material within to flow out and be dissolved. The rest of the capsule is rapidly dissolved 

 after the escaped contents have disappeared. 



Reaction with pyrogallic add begins in 15 seconds and is over in Ij^ minutes. It begins at the 

 hilum, which swells somewhat, and a bubble appears which first increases then decreases in size 

 and finally disappears. Fine stria3 radiate from the hilum in all directions. The less resistant 

 inner starch is gelatinized, and the more resistant outer starch forms a dense striated band at the 

 margin, which as the grain swells becomes thin and transparent, especially at the distal end. The 

 swollen grains are large, crumpled, and sacculated at the distal end and do not retain much of the 

 original form of the grain. 



With ferric chloride reaction begins in some grains in a miiuite and is over in 20 minutes. The 

 reaction originates at the distal end, which is fissured internally in one or more places, and from 

 these fissures gelatinized starch protrudes beneath the capsule. This process of gelatinization 

 proceeds around the margin of the grain on each side and sometimes reaches the proximal end. 

 Then it extends inward over the interior and denser portion of the grain, which is first split by 

 fissures into small pieces that are separated from the main imgelatinized mass by wide bands of 

 gelatinized starch and later are gelatinized themselves. The gelatinized grains are large, saccu- 

 lated, crumpled, and distorted, and do not retain any of the original form of the grain. 



Reaction with Purdy's solution begins at once. It is over in one-third of the grains in a minute, 

 in three-fourths in 3 minutes, and in nearly all in 12 minutes. It appears to be qualitatively the same 

 as that with pyrogallic acid. 



STARCH OF PUSCHKINIA SCILLOIDES VAR. LIBANOTICA. (Plate 37, figs. 219 and 220. Chart 148.) 



General Characteristics. In for??! the grains are usually simple, and are isolated except a few 

 in aggregates. Compound grains are not unusual and consist generally of one large grain with 

 one or more smaller grains at its sides or distal end, the whole being surrounded by one, two, or more 

 lamellse. The components of such grains are frequently partially separated by fissures. There 

 are a few aggregates, and these consist usually of a large grain having one or more small grains 

 attached generally at the distal end, but sometimes at the side. A few of the grains have poorly 

 defined pressure facets at the distal ends. The surface is rather irregular, due in the single grains 

 to the additions of starch, usually lamellated, to the distal end and sides, the longitudinal axis of 

 which additions does not correspond to that of the major part of the grain; and in the double grain 



