674 



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



in about 75 per cent of the grains and 79 per cent of the 

 total starch in 15 minutes; in more than 99 per cent 

 of the grains and total starch in 30 minutes. (Chart 

 D 454.) 



The hilum is as distinct as in /. persica var. purpurea, 

 and a small bubble is not so often formed there as in 

 that starch, but more often than in /. sindjarensis. 

 The lamellae are as distinct as in /. persica var. purpurea. 

 The grains become more refractive in appearance when 

 the reagent is added, and the first part to show this in- 

 creased refractivity is a rather narrow band about the 

 margin, as in /. persica var. purpurea. Gelatinization 

 begins at separate points on the distal margin, which 

 has previously been invaded by short, wide cracks that 

 are more numerous and deeper than in /. persica var. 

 purpurea. The progress of gelatinization is not so 

 smooth as in either parent, and there is more fissuring, 

 and in some cases actual granulation of the starch 

 just preceding gelatinization than in even /. persica 

 var. purpurea. The gelatinized grains are much swollen, 

 have as thin a capsule, and are as distorted as in /. persica 

 var. purpurea. 



In this reaction I. pursind shows qualitatively a 

 closer relationship to /. persica var. purpurea than to 

 I. sindjarensis. Phenomena characteristic of one parent 

 are sometimes accentuated in the hybrid. 



The reaction with calcium nitrate begins imme- 

 diately. Complete gelatinization occurs in about 5 per 

 cent of the entire number of grains and 28 per cent of 

 the total starch in 5 minutes; in about 37 per cent of the 

 grains and 80 per cent of the total starch in 15 minutes ; 

 in about 58 per cent of the grains and 90 per cent of the 

 total starch in 30 minutes; in about 70 per cent of the 

 grains and 95 per cent of the total starch in 45 minutes ; 

 in about 85 per cent of the grains and 98 per cent of the 

 total starch in 60 minutes. (Chart D 455.) 



The reaction with uranium nitrate begins in a few 

 grains immediately. Complete gelatinization occurs in 

 about 5 per cent of the entire number of grains and 17 

 per cent of the total starch in 5 minutes; in about 44 

 per cent of the grains and 75 per cent of the total starch 

 in 15 minutes; in about 63 per cent of the grains and 

 90 per cent of the total starch in 30 minutes; in about 

 70 per cent of the grains and 96 per cent of the total 

 starch in 45 minutes ; in about 77 per cent of the grains 

 and 98 per cent of the total starch in 60 minutes. (Chart 

 D456.) 



The reaction with strontium nitrate begins imme- 

 diately. Complete gelatinization occurs in about 9 per 

 cent of the entire number of grains and 39 per cent of 

 the total starch in 5 minutes ; in about 65 per cent of the 

 grains and 90 per cent of the total starch in 15 minutes ; 

 in about 93 per cent of the grains and in more than 99 

 per cent of the total starch in 30 minutes. (Chart 

 D 457.) 



The reaction with cobalt nitrate begins in 30 seconds. 

 Complete gelatinization occurs in about 2 per cent of the 

 entire number of grains and 6 per cent of the total starch 

 in 5 minutes; in about 6 per cent of the grains and 26 

 per cent of the total starch in 15 minutes; in about 7 per 

 cent of the grains and 36 per cent of the total starch in 30 

 minutes; in about 9 per cent of the grains and 43 per 

 cent of the total starch in 45 minutes ; in about the same 

 percentage of the grains and 44 per cent of the total 

 starch in 60 minutes. (Chart D 458.) 



The reaction with copper nitrate begins immediately. 

 Complete gelatinization occurs in about 7 per cent of the 

 entire number of grains and 43 per cent of the total 

 starch in 5 minutes; in about 45 per cent of the grains 

 and 80 per cent of the total starch in 15 minutes ; in about 

 72 per cent of the grains and 95 per cent of the total 

 starch in 30 minutes ; in about 74 per cent of the grains 

 and 97 per cent of the total starch in 45 minutes; in 

 about 80 per cent of the grains and 99 per cent of the 

 total starch in 60 minutes. (Chart D 459.) 



The reaction with cupric chloride begins immediately. 

 Complete gelatinization occurs in about 16 per cent of 

 the grains and 49 per cent of the total starch in 5 min- 

 utes; in about 56 per cent of the grains and 95 per cent 

 of the total starch in 15 minutes; in about 85 per cent 

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

 starch in 30 minutes ; in about 90 per cent of the grains 

 and in more than 99 per cent of the total starch in 45 

 minutes. ( Chart D 460.) 



The reaction with barium chloride begins in a few 

 grains in 1 minute. Complete gelatinization occurs in 

 about 3 per cent of the entire number of grains and 7 

 per cent of the total starch in 5 minutes ; in about 4 per 

 cent of the grains and 12 per cent of the total starch 

 in 15 minutes; in about 6 per cent of the grains and 22 

 per cent of the total starch in 30 minutes; in about the 

 same percentage of the grains and 27 per cent of the 

 total starch in 45 minutes ; in about the same percentage 

 of the grains and 31 per cent of the total starch in 60 

 minutes. ( Chart D 461.) 



The reaction with mercuric chloride begins imme- 

 diately. Complete gelatinization occurs in about 5 per 

 cent of the entire number of grains and 35 per cent of the 

 total starch in 5 minutes; in about 45 per cent of the 

 grains and 82 per cent of the total starch in 15 minutes; 

 in about 65 per cent of the grains and 90 per cent of the 

 total starch in 30 minutes; in about 68 per cent of the 

 grains and 97 per cent of the total starch in 45 minutes; 

 little if any farther advance in 60 minutes. (Chart 

 D 462.) 



A larger percentage of the grains are gelatinized with 

 the exception of the margin than in the parents, but 

 there are fewer entire grains which are resistant than in 

 the parents; hence, the percentages of gelatinization of 

 the grains and total starch show a greater variation than 

 in the parents. 



