662 



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



7. pallida queen of may and 1.2 C. less than that of I. 

 cengialti. It is therefore closer to 7. cengialti than to I. 

 pallida queen of may. 



EFFECTS OF VARIOUS REAGENTS. 



The reaction with chloral hydrate begins in 30 sec- 

 onds. Complete gelatinization occurs in about 8 per 

 cent of the entire number of grains and 14 per cent of 

 the total starch in 5 minutes; in about 58 per cent of 

 the grains and 72 per cent of the total starch in 15 min- 

 utes ; in about 90 per cent of the grains and 95 per cent 

 of the total starch in 30 minutes ; in about 98 per cent 

 of the grains and 99 per cent of the total starch in 45 

 minutes. (Chart D 421.) 



Experiment repeated with practically precisely the 

 same percentages. 



The hilum becomes distinct, attended by the forma- 

 tion of a bubble in a smaller majority than in either 

 parent. The lamellae, as in I. pallida queen of may, 

 are usually not visible. The grains become more refrac- 

 tive after the addition of the reagent, and the first part 

 of the grain to show this change is a rather narrow band 

 of starch at the margin which is as narrow and as 

 refractive as in /. pallida queen of may. Gelatinization, 

 as in both parents, begins at the corners of the distal 

 margin, and in a large majority of the grains it pro- 

 gresses as in I. pallida queen of may, but in a small 

 minority as in I. cengialti. In a very few grains it also 

 begins at the proximal end immediately after it starts 

 at the distal as in that starch. The gelatinized grains 

 are as much swollen, have rather thick capsules, and 

 are as distorted as in I. pallida queen of may. In this 

 reaction I. mrs. alan grey shows qualitatively a some- 

 what closer relationship to 7. pallida queen of may than 

 to I. cengialti. 



The reaction with chromic acid begins in 1 minute. 

 Complete gelatinization occurs in about 2 per cent of 

 the grains and 6 per cent of the total starch in 5 minutes ; 

 in about 11 per cent of the grains and 57 per cent of the 

 total starch in 15 minutes; in about 21 per cent of the 

 grains and 86 per cent of the total starch in 30 minutes ; 

 in about 43 per cent of the grains and 95 per cent of 

 the total starch in 45 minutes; in about 67 per cent 

 of the grains and 98 per cent of the total starch in 60 

 minutes. (Chart D 422.) 



The reaction with pyrogallic acid begins in 1 minute. 

 Complete gelatinization occurs in about 1 per cent of the 

 entire number of grains and 5 per cent of the total 

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

 and 16 per cent of the total starch in 15 minutes; in 

 about 12 per cent of the grains and 56 per cent of the 

 total starch in 30 minutes; in about the same percentage 

 of the grains and 66 per cent of the total starch in 45 

 minutes; in about 20 per cent of the grains and 78 

 per cent of the total starch in 60 minutes. (Chart D 423.) 



The reaction with nitric acid begins immediately. 

 Complete gelatinization occurs in about 2 per cent of 

 the entire number of grains and 10 per cent of the total 

 starch in 5 minutes; in about 21 per cent of the grains 

 and 63 per cent of the total starch in 15 minutes; in 

 about 29 per cent of the grains and 71 per cent of the 

 total starch in 30 minutes ; in about 37 per cent of the 

 grains and 80 per cent of the total starch in 45 minutes; 



in about the same percentage of the grains and 83 per cent 

 of the total starch in 60 minutes. (Chart D424.) 



The reaction with sulphuric acid begins immediately. 

 Complete gelatinization occurs in about 64 per cent of the 

 entire number of grains and 93 per cent of the total 

 starch in 2 minutes ; in about 85 per cent of the grains 

 and in more than 99 per cent of the total starch in 5 

 minutes. ( Chart D 425.) 



The reaction with hydrochloric acid begins imme- 

 diately. Complete gelatinization occurs in about 10 per 

 cent of the entire number of grains and 20 per cent of 

 the total starch in 5 minutes ; in about 14 per cent of the 

 grains and 62 per cent of the total starch in 15 minutes ; 

 in about 31 per cent of the grains and 75 per cent of the 

 total starch in 30 minutes ; in about the same percentage 

 of the grains and 86 per cent of the total starch in 45 

 minutes; little if any further advance in 00 minutes. 

 (Chart D426.) 



The hilum and lamellae are as distinct as in I. pallida 

 queen of may. Gelatinization begins at the hilum and 

 progresses according to two methods. The first, which 

 is seen in a great majority of the grains, is the same as 

 that described for all the grains of I. pallida queen of 

 may. The second, which is seen in a few grains, is the 

 same as that described for a moderate minority of the 

 grains of 7. cengialti. The gelatinized grains are as 

 much swollen, have as thin capsules, and are as much 

 distorted as in 7. pallida queen of may. In this reaction 

 7. mrs. alan grey shows qualitatively a closer relationship 

 to 7. pallida queen of may than to 7. cengialti. 



The reaction with potassium hydroxide begins imme- 

 diately. Complete gelatinization occurs in about 26 per 

 cent of the entire number of grains and 66 per cent of 

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

 grains and 73 per cent of the total starch in 15 minutes; 

 in about 44 per cent of the grains and 81 per cent of 

 the total starch in 30 minutes; in about 50 per cent of 

 the grains and 88 per cent of the total starch in 45 min- 

 utes ; in about 50 per cent of the grains and 90 per cent 

 of the total starch in 60 minutes. (Chart D 427.) 



The reaction with potassium iodide begins imme- 

 diately. Complete gelatinization occurs in about 3 per 

 cent of the entire number of grains and 37 per cent of 

 the total starch in 5 minutes; in about 26 per cent of the 

 grains and 53 per cent of the total starch in 15 minutes; 

 in about 40 per cent of the grains and 77 per cent of the 

 total starch in 30 minutes; in about 46 per cent of the 

 grains and 81 per cent of the total starch in 45 minutes; 

 in about the same percentage of the grains and 83 per 

 cent of the total starch in 60 minutes. (Chart D428.) 



The hilum and lamellae are as distinct as in I. pallida 

 queen of may. Gelatinization is preceded by granular 

 formation in the portion of the grain comprehended 

 between 2 pre-existing fissures as in both parents, and 

 the granules are as fine and as regularly arranged as in 

 7. cengialti. Gelatinization proceeds according to two 

 methods which are the same as the two described under 

 7. pallida queen of may, except that the second is seen 

 in a somewhat larger proportion of grains than in that 

 starch, but in a somewhat smaller proportion than in 7. 

 cengialti. The gelatinized grains are as much swollen 

 and no more distorted than in I. pallida quer.n of may, 

 but have as thick capsules as in 7. cengialti. In this 



