698 



DATA OF PROPERTIES OF STARCHES OF PARENT- AND HYBRID-STOCKS. 



are not distinct but are visible in all the grains. Gelati- 

 nization begins at the hilum, which enlarges more rapidly 

 toward the proximal than toward the distal end. Two 

 fissures are formed which extend from either side of the 

 hilum about three-fourths of the way from the hilum 

 to the distal margin. The part of the grain between 

 these fissures gelatinizes rather slowly, usually without 

 any preliminary fissuring, so that the gelatinizing grain 

 presents the appearance of a broad, homogeneous-looking 

 band of refractive material, surrounding a central, clear 

 space. This band is much broader and thicker at the 

 distal than at the proximal end. It grows gradually 

 thinner and more nearly transparent, and is finally gela- 

 tinized. The gelatinized grains are much swollen, have 

 rather thin walls, and are considerably distorted. 



NOTE. The pyrogallic-acid solution used in the qualitative 

 experiments was composed of 6 grams of pyrognllic acid, 0.3 

 gram of oxalic acid, and 35 c.c. of distilled water, and there- 

 fore stronger than the solution in the quantitative reactions. 



Comparison of the pyrogallic-acid reactions between 

 B. socotrana and B. single crimson scarlet shows : 



The hilum and lamellae are more distinct than in 

 B. single crimson scarlet. Gelatinization begins at the 

 hilum which swells slightly, but no more in the direction 

 of the proximal than of the distal end. Two fissures 

 appear which extend from either side of the hilum only 

 about half the distance between the hilum and the distal 

 end, and proceeds from this point quite differently' from 

 that seen in B. single crimson scarlet. The starch be- 

 tween the 2 fissures is divided by a double row of slanting 

 fissures which become more distinct as the grain swells 

 somewhat. Finally, it is gelatinized slowly, leaving a 

 refractive, granular residue at the distal end. The 

 material at the proximal and distal margins and sides 

 forms a thick, refractive, lamellated marginal baud. No 

 further change takes place within an hour except an 

 increased ref ractivity of the whole grain. 



The reaction with nitric acid begins immediately. 

 Complete gelatinization occurs in 100 per cent of the 

 entire number of grains and total starch in 15 seconds. 

 (Chart D509.) 



The hilum becomes distinct in all the grains, attended 

 by the formation of a bubble in a majority of them. 

 The lamellae are not very distinct, but are visible. Gela- 

 tinization begins at the hilum which swells very rapidly, 

 especially toward the proximal end. Two fissures appear 

 extending from either side of the hilum to about half the 

 distance to the distal end. The portion comprehended 

 between them is not fissured, but gelatinizes very rapidly, 

 so that the gelatinizing grain shows merely a refractive, 

 homogeneous-looking marginal band surrounding a cen- 

 tral area. This band is broader and thicker at the distal 

 than at the proximal end, and the distal starch is the 

 last to be completely gelatinized. If a bubble is present 

 at the hilum it first swells as the hilum enlarges, then 

 shrinks, and finally disappears, causing an invagination 

 of the marginal band and capsule at the side. The gela- 

 tinized grains are much swollen, have rather thin cap- 

 sules, and are not much distorted. 



Comparison of the nitric-acid reactions between B. 

 socotrana and B. single crimson scarlet shows : 



The hilum becomes distinct in all the grains, unat- 

 tended by the formation of a bubble. The lamellae are 



more distinct than in B. single crimson scarlet. Gela- 

 tinization begins at the hilum, but proceeds differently 

 from B. single crimson scarlet. Two fissures are formed 

 extending from the hilum on either side nearly to the 

 distal margin. The starch comprehended between them 

 and immediately distal to the hilum is divided by a 

 double row of slanting fissures which are at first indistinct 

 but later become distinct. This fissured material is 

 slowly gelatinized, leaving small pointed protuberances 

 of refractive starch projecting from the sides into the 

 area of the swelling grain. This is as far as the reaction 

 ever seems to go in the normal grains. 



The reaction with sulphuric acid begins immediately. 

 Complete gelatinization occurs in about 97 per cent of 

 the entire number of grains and 98 per cent of the total 

 starch in 15 seconds; in 100 per cent of the grains and 

 total starch in 30 seconds. (Chart D 510.) 



The reaction with hydrochloric acid begins imme- 

 diately. Complete gelatinization occurs in about 92 per 

 cent of the entire number of grains and 96 per cent of 

 the total starch in 30 seconds; in 100 per cent of the 

 grains and total starch in 1 minute. (Chart D 511.) 



The reaction with potassium hydroxide begins imme- 

 diately. Complete gelatinizatiou occurs in 100 per cent 

 of the entire number of grains and total starch in 10 

 seconds or earlier (apparently instantaneous). (Chart 

 D512.) 



The reaction with potassium iodide begins imme- 

 diately. Complete gelatinization occurs in about 85 per 

 cent of the entire number of graifte and 99 per cent of 

 the total starch in one minute and 30 seconds. (Chart 

 D513.) 



The reaction with potassium sulphocyanate begins 

 immediately.- Complete gelatinization occurs in about 80 

 per cent of the entire number of grains and in more 

 than 99 per cent of the total starch in 30 seconds ; in about 

 90 per cent of the grains and in more than 99 per cent 

 of the total starch in 1 minute. (Chart D 514.) 



The reaction with potassium sulphide begins imme- 

 diately. Complete gelatinization is apparently instan- 

 taneous, as all grains are gelatinized as soon as an obser- 

 vation can be made. (Chart D 515.) 



The reaction with sodium hydroxide begins imme- 

 diately. Complete gelatinization occurs in 100 per cent 

 of the grains and total starch in 15 seconds. (Chart 

 D516.) 



The reaction with sodium sulphide begins imme- 

 diately. Complete gelatinization occurs in about 97 per 

 cent of the entire number of grains and in more than 99 

 per cent of the total starch in 1 minute. (Chart D 517.) 

 The reaction with sodium salicylate begins imme- 

 diately. Complete gelatinization occurs in about 93 per 

 cent of the grains and 97 per cent of the total starch in 

 3 minutes ; in more than 99 per cent of the grains and 

 total starch in 5 minutes. (Chart D 518.) 



The reaction with calcium nitrate begins immediately. 

 Complete gelatinization occurs in 88 per cent of the 

 entire number of grains and 99 per cent of the total starch 

 in 2 minutes ; in about 95 per cent of the grains and in 

 more than 99 per cent of the total starch in 5 minutes. 

 (Chart D519.) 



The reaction with uranium nitrate begins imme- 

 diately. Complete gelatinization occurs in about 97 per 

 cent of the entire number of grains and in more than 99 



