412 



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



Aniline Reactions. 



With gentian violet the grains immediately stain very 

 lightly, a little lighter than in II. ossultan, and in half 

 an hour they become moderately light to moderate in 

 color (value 48), lighter and with more variation in depth 

 of the individual grains than in //. ossultan. 



With safranin the grains immediately stain very 

 lightly, a little lighter than in II. ossultan, and in half 

 an hour they stain from light to moderately deep, the 

 mean being moderate (value 50), and there is a greater 

 variation in the depth of the individual grains with the 

 mean lighter than in II. ossultan. 



Temperature Reactions. 

 The majority of the grains are gelatinized at 71° to 

 73° C. and of all but very rare grains at 73° to 74° C, 

 mean 73.5° C. 



Effects of Various Reagents. 



The reaction with chloral hydrate begins in a few 

 grains in 1 minute. Complete gelatinization occurs in 

 about 2 per cent of the entire number of grains and 3 

 per cent of the total starch in 5 minutes ; in about 16 per 

 cent of the grains and 19 per cent of the total starch in 

 15 minutes; in about 25 per cent of the grains and 28 

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

 per cent of the grains and 39 per cent of the total starch 

 in 45 minutes ; in about 41 per cent of the grains and 42 

 per cent of the total starch in 60 minutes. (Chart D 43.) 



One or more bubbles, more frequently the former, 

 may appear at the hilum ; the bubble may expand to con- 

 siderable size, in some grains more tham in II. ossultan ; 

 and a cleft which is present at the hilum in a number of 

 untreated grains becomes much enlarged and refractive, 

 and is more frequently observed than in H. ossultan. The 

 lamellae do not become more distinct ; but the entire grain 

 is more refractive and a border of slightly greater refrac- 

 tivity appears around the main body of the grain as in 

 //. ossultan. A delicate fissure may proceed from or 

 intersect the hilum, which becomes deeper and branched 

 as the reaction proceeds, and this is a little more prom- 

 inent than in H. ossultan. Gelatinization begins and 

 proceeds according to the methods described in II. ossul- 

 tan, but the reaction much more frequently begins at 

 the distal margin and proceeds towards the proximal end 

 than in that species. The starch is disorganized into 

 refractive granules that are a little more resistant than 

 in II. ossultan. 



The gelatinized grains are swollen and considerably 

 distorted so that they do not resemble the form of the 

 untreated grain, about the same as in H. ossultan. 



The reaction with chromic acid begins in 1 minute. 

 Complete gelatinization occurs in less than 0.5 per cent 

 of the entire number of grains and 1 per cent of the 

 total starch in 5 minutes; still in less than 0.5 per cent 

 of the grains and 20 per cent of the total starch in 15 

 minutes ; in about 50 per cent of the grains and 75 per 

 cent of the total starch in 20 minutes; in about 62 per 

 cent of the grains and 90 per cent of the total starch in 

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

 total starch in 30 minutes. (Chart D 44.) 



The reaction with pyrogallic acid begins in a few 

 grains in 1 minute. Complete gelatinization occurs in 

 about 4 per cent of the entire number of grains and 5 per 

 cent of the total starch in 5 minutes; in about 36 per cent 



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

 minutes; in about 78 per cent of the grains and 89 per 

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

 cent of the grains and 92 per cent of the total starch in 

 45 minutes; in about 90 per cent of the grains and 96 

 per cent of the total starch in 60 minutes. (Chart D 45.) 



The reaction with nitric acid begins in a few grains in 

 1 minute. Complete gelatinization occurs in about 1 per 

 cent of the entire number of grains and 2 per cent of the 

 total starch in 5 minutes ; in about 2 per cent of the 

 grains and 6 per cent of the total starch in 15 minutes; 

 in about 10 per cent of the grains and 16 per cent of the 

 total starch in 30 minutes; in about 15 per cent of the 

 grains and 33 per cent of the total starch in 45 minutes ; 

 in about 17 per cent of the grains and 50 per cent of the 

 total starch in 60 minutes. (Chart D46.) 



The hilum swells and a bubble is somewhat more fre- 

 quently observed than in H. ossultan. The fissures pres- 

 ent in the untreated grain become enlarged and more 

 refractive, more frequent and refractive than in H. ossul- 

 tan, and the refractivity is gradually lost without the 

 apparent expulsion of a bubble. The grain becomes 

 refractive throughout its entire extent and occasionally 

 a few lamellfe become more distinct, but they are little 

 more frequently demonstrable than in H. ossultan. A 

 border which is but slightly more refractive than the 

 main body of the grain is quite common and may be 

 separated from the main body of the grain by a distinct 

 clear lamella as in II. osultan. Either one or two fissures 

 appear according to the shape of the grain; more fre- 

 quently one is present, which either proceeds distally 

 from the hilum or may intersect this point ; and the fis- 

 sures are much deeper and more profusely branched than 

 in H. ossultan. The progress of the reaction is much 

 varied and the disorganization of the lamelhe is gener- 

 ally accompanied by the appearance of large refractive 

 granules, which have the same arrangement but are more 

 resistant than in H. ossultan. 



The gelatinized grains are much swollen and slightly 

 to considerably distorted so that they do not usually re- 

 semble the untreated grain as in H. ossultan. A few 

 grains are found which contain no refractive granules, 

 less than in H. ossultan. Fewer grains undergo com- 

 plete gelatinization, but a large number are partially 

 gelatinized and hence the difference between complete 

 and total gelatinization is greater than in II. ossultan. 

 The capsule of the gelatinized grains is less frequently 

 slashed in one or more places than in H. ossultan. 



The reaction with sulphuric acid begins immediately. 

 Complete gelatinization occurs in about 45 per cent of 

 the entire number of grains and 70 per cent of the total 

 starch in 5 minutes; in about 90 per cent of the grains 

 and 96 per cent of the total starch in 15 minutes; in 

 about 98 per cent of the grains and more than 99 per 

 cent of the total starch in 30 minutes. (Chart D 47.) 



The reaction with hydrochloric acid begins in a few 

 grains immediately. Complete gelatinization occurs in 

 about 3 per cent of the entire number of grains and 5 

 per cent of the total starch in 5 minutes; in about 11 

 per cent of the grains and 41 per cent of the total starch 

 in 15 minutes ; in about 33 per cent of the grains and 

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

 per cent of the grains and 80 per cent of the total starch 



