GENUS HYACINTHUS. 571 



color deepens rather slowly. After heating in water until all the grains are completely gelatinized, the 

 solution colors a deep greenish-blue and the gelatinized grains a deep purplish-blue on the addition of 

 iodine. After boiling for 2 niiiuites the solution colors very deeply an indigo-blue and the grain- 

 residues a deep blue. The capsules all color a deep heliotrope to a wine-red with an excess of iodine. 



Staining Reactions. With gentian violet the grains begin to stain at once slightly and in 30 min- 

 utes they are fairly stained. 



With safraiiin the grains begin to stain at once and in 30 minutes they are fairly deeply stained. 



Temperature Reaction. The temperature of gelatinization is G6 to 68 C, mean 67. 



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

 tically all the grains are gelatinized in 5 minutes and all in 10 minutes. The reaction begins at the dis- 

 tal end and spreads around the margin, the more prominent portions of the latter becoming darker 

 than the rest. These portions swell somewhat, and this process moves inward over the rest of the 

 grain, the part about the hilum being the last to be affected. When the hilum is reached a bubble is 

 often seen to form here, which increases in size, then becomes smaller, and finally disappears. The 

 swollen grains are fairly large, of a uniform dark color, and retain some of their original shape. 



The reaction with chromic acid begins at once. Some of the grains are dissolved in a minute, 

 nearly all in IJ^ minutes, and all in 2 minutes. The starch about the hilum becomes granular and 

 gelatinous, and the part of the grain between the hilum and the distal end is divided by a number 

 of longitudinal fissures and converted into an irregular mass; the rest of the grain shows a number 

 of fine, radial striae. The grain swells and a bubble appears at the hilum, which increases in size, 

 then becomes smaller, and finally disappears. The granular mass in the interior of the grain becomes 

 more and more gelatinous, and the more resistant starch is gathered at the margin in the form of 

 a striated band or capsule, which shows two or three alternate refractive and non-refractive lines, 

 apparently the remains of the lamellae. This capsule becomes thin and transparent and is dissolved 

 at the distal end or on one side. The gelatinous starch within the capsule flows out and is dissolved, 

 the capsule dissolving later. 



The reaction with pyrogallic acid begins immediately. Many grains are gelatinized in 10 sec- 

 onds, almost all in 30 seconds, all but a few resistant grains in 40 seconds, and all in a minute. The 

 starch about the hilum is transformed into a clear, semiliquid, gelatinized state; the grain becomes 

 covered by fine striae; and a bubble often appears at the hilum, which increases and then decreases 

 in size, and finally disappears. The less resistant inner starch becomes gelatinous, attended by 

 swelling of the whole grain, and the more resistant outer starch forms a thick, finely striated band 

 at the margin, and this band or capsule becomes thinner and clearer and sometimes becomes invag- 

 inated just at the proximal end. The grains when fully swollen are large, the marginal band or cap- 

 sule is rather thick, fairly transparent, and somewhat wrinkled and sacculated. Thej' do not retain 

 much of the original form of the grain. 



With ferric chloride the reaction begins in some grains immediately. A few grains are gelatin- 

 ized in a minute, the majority in 5 minutes, and nearly all in 10 minutes. The rare very resistant 

 grains are not fully gelatinized until 15 to 20 minutes. The reaction begins at the distal end, which 

 is fissured internally in one or two places, and the starch which is gelatinized at these points pro- 

 trudes beneath the capsule. This process spreads to all parts of the distal end and nearby portions 

 of the grain, and from here it extends upward and inward over the rest of the grain. A bubble in 

 the meanwhile forms at the hilum, and as the reaction nears this point the bubble increases and 

 then decreases in size and finally disappears. The portion of starch as yet ungelatinized is divided 

 by fissures into two or three parts which become widely separated by bands of gelatinized starch, 

 and then themselves become gelatinized independently of each other. The gelatinized grains are 

 verj' large, sacculated, folded, and distorted. They do not retain much of the original form. 



Reaction with Purdy's solution begins in some grains at once and in all in a minute. In 15 

 minutes all are partially gelatinized and in 30 minutes all are completely or nearly completely gelatin- 

 ized. As far as the reaction goes, it appears to be the same qualitatively as that with pyrogallic acid. 



STARCH OF HYACINTHUS ORIENTALIS VAR. ALBULUS (WHITE). 

 (Plate 41, figs. 243 and 244. Chart 160.) 



Histological Characteristics. In form both simple and compound grains are present. There 

 are many aggregates, usually consisting of two to five components. Isolated grains with pressure 

 facets are occasionally found, and a few small clumps are observed. The outline of the grain 



