768 



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



minute; in all but very rare grains more than 99 per 

 cent in 2 minutes. The reaction is qualitatively about 

 the same as in the parents ; the reaction in all three being 

 so rapid that minute differences can not be determined. 

 The gelatinized grains are swollen and considerably dis- 

 torted, somewhat less than in C. lowianum, but more 

 than in C. eburneum. They do not usually resemble the 

 shape of the untreated grain, about as in G. lowianum, 

 less frequently than in G. eburneum. 



The reaction with potassium sulphide begins imme- 

 diately. Complete gelatinization occurs in all but a few 

 grains in 15 seconds, and in all the grains in 1 minute 

 and 15 seconds. 



The reaction with sodium hydroxide begins imme- 

 diately. Complete gelatinization occurs in all but rare 

 grains in 30 seconds, and in all grains in 1 minute. 



The reaction is so rapid that the minute steps can not 

 be studied, as in both parents. The gelatinized grains 

 are much swollen and distorted, about as much dis- 

 torted as in G. lowianum; more than in C. eburneum; 

 the wall is slightly thicker than in G. lowianum, but 

 thinner than in C. eburneum. The gelatinized grains 

 do not usually resemble the untreated grains, as in G. 

 lowianum; less resemblance is seen than in G. eburneum. 



The reaction with sodium sulphide begins imme- 

 diately. Complete gelatinization occurs in about 92 

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

 of the total starch in 1 minute; in about 98 per cent 

 of the grains and over 99 per cent of the total starch in 

 2 minutes; in over 99 per cent of both the grains and 

 total starch in 5 minutes. 



The reaction with sodium salicylate begins immedi- 

 ately. Complete gelatinization occurs in about 80 per 

 cent of the entire number of grains and 81 per cent of the 

 total starch in 1 minute; in about 94 per cent of the 

 grains and 95 per cent of the total starch in 2 minutes ; 

 in about 98 per cent of the grains and 99 per cent of 

 the total starch in 3 minutes. 



The hilum, as in the parents, is very distinct, and 

 a small bubble is formed there. The lamellae are, at 

 first, as distinct as in C. lowianum, and later become 

 obscured. A narrow, refractive band is formed quickly 

 about the margin of the grains and remains there as 

 gelatinization proceeds. Gelatinization as in C. lowi- 

 anum begins at the distal margin in most of the grains, 

 and in some at various points on the margin as in G. 

 eburneum. The progress of gelatinization in most of 

 the grains is the same as that described under C. lowi- 

 anum, and in a few the same as under G. eburneum. 

 The gelatinized grains are large and much distorted and 

 retain less of the form of the untreated grain than those 

 of G. lowianum, but more than those of C. eburneum. In 

 this reaction C. eburneo-lowianum shows qualitatively a 

 closer relationship to G. lowianum than to G. eburneum. 



The reaction with calcium nitrate begins immedi- 

 ately. Complete gelatinization occurs in about 66 per 

 cent of the entire number of grains and 80 per cent of 

 the total starch in 30 seconds ; in about 84 per cent of 

 the grains and 95 per cent of the total starch in 1 

 minute; in about 95 per cent of the grains and 99 per 

 cent of the total starch in 2 minutes. 



The reaction with uranium nitrate begins imme- 

 diately. Complete gelatinization occurs in about 71 per 



cent of the entire number of grains and 90 per cent of 

 the total starch in 1 minute; in about 86 per cent of the 

 grains and 95 per cent of the total starch in 2 minutes; 

 in about 97 per cent of the grains and in over 99 per 

 cent of the total starch in 5 minutes. 



The reaction with strontium nitrate begins imme- 

 diately. The majority of the grains are gelatinized in 15 

 seconds, and all but rare grains (over 99 per cent of 

 both the grains and total starch) in 45 seconds; these 

 grains which are only in the proportion of 1 in several 

 hundred are very resistant. 



The reaction with cobalt nitrate begins immediately. 

 Complete gelatinization occurs in about 84 per cent of the 

 entire number of grains and 90 per cent of the total starch 

 in 1 minute ; in about 95 per cent of the grains and 97 

 per cent of the total starch in 2 minutes; in about 98 per 

 cent of the grains and over 99 per cent of the total starch 

 in 5 minutes. 



The reaction with copper nitrate begins immediately. 

 Complete gelatinization occurs in all but rare grains in 1 

 minute, in all (100 per cent of both the grains and total 

 starch) in 1 minute and 15 seconds. 



The reaction with cupric chloride begins immedi- 

 ately. Complete gelatinization occurs in about 75 per 

 cent of the entire number of grains and 86 per cent of the 

 total starch in 1 minute; in about 78 per cent of the 

 grains and 90 per cent of the total starch in 2 minutes ; 

 in about 93 per cent of the grains and 97 per cent of the 

 total starch in 5 minutes; in about 99 per cent of the 

 grains and in over 99 per cent of the total starch in 

 15 minutes. 



The reaction with barium chloride begins in a few 

 grains immediately. Complete gelatinization occurs in 

 about 8 per cent of the entire number of grains and 15 

 per cent of the total starch in 5 minutes ; in about 33 per 

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

 15 minutes; in about 49 per cent of the grains and 55 

 per cent of the total starch in 30 minutes; in about 53 

 per cent of the grains and 62 per cent of the total starch 

 in 45 minutes; in about 62 per cent of the grains and 67 

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

 D 618.) 



The hilum is distinct as in C. lowianum, and the 

 lamellae are not so distinct, but more distinct than in 

 G. eburneum. Gelatinization, as in the parents, begins 

 at the hilum, and the progress of gelatinization is the 

 same as in G. lowianum, except that fissuration is not so 

 extensive, but more extensive than in G. eburneum, and 

 lamellation of the marginal band is less obvious. The 

 gelatinized grains are as large and as distorted as in 

 G. lowianum. In this reaction G. eburneo-lowianum is 

 closer, qualitatively, to G. lowianum than to C. eburneum. 



The reaction with mercuric chloride begins imme- 

 diately. Complete gelatinization occurs in about 70 per 

 cent of the entire number of grains and 78 per cent of 

 the total starch in 1 minute ; in about 80 per cent of the 

 grains and 91 per cent of the total starch in 2 minutes ; 

 in about 95 per cent of the total starch in 3 minutes ; in 

 about 91 per cent of the grains and 98 per cent of the 

 total starch in 5 minutes; in about 98 per cent of the 

 grains and in over 99 per cent of the total starch in 15 

 minutes. 



