780 



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



Shreds of the capsule often remain after the rest has 

 dissolved. No true completely gelatinized grains are 

 noted. 



The reaction with pyrogallic acid begins in 1 minute. 

 Complete gelatinization occurs in but rare grains, less 

 than 0.5 per cent of the entire number, and 25 per cent 

 of the total starch is gelatinized in 5 minutes; still but 

 rare grains are completely gelatinized and 66 per cent 

 of the total starch gelatinized in 30 minutes; complete 

 gelatinization occurs in about 31 per cent of the grains 

 and 93 per cent of the total starch in 30 minutes; in 

 about 41 per cent of the grains and 96 per cent of the 

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

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

 (Chart D 629.) 



The reaction with nitric acid begins immediately. 

 Complete gelatinization occurs in about 56 per cent of 

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

 starch in 5 minutes ; in about 63 per cent of the grains 

 and 93 per cent of the total starch in 15 minutes; in 

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

 total starch in 30 minutes ; little if any further advance 

 in 45 and 60 minutes, respectively. (Chart D 630.) 



No bubble occurs at the hilum, and rarely definite 

 fissures proceed from the hilum, such as found in C. 

 vestita var. rubro-oculata. The granules in the mesial 

 region are more refractive throughout the entire portion, 

 gelatinization of them is more rapid towards the distal 

 end of narrow or one side of rounded grains, but the 

 group of larger refractive granules at the proximal 

 end is not so marked as in C. vestita var. rubro-oculata. 

 The marginal lamella or lamella} of rounded grains and 

 that at the proximal end and sides of slender grains break 

 into very refractive linear granules, not commonly ob- 

 served in C. vestita var. rubro-oculata. During gela- 

 tinization of this outermost layer, it may break into small 

 segments and the process is always accompanied by much 

 distortion. The gelatinized grains are swollen and much 

 distorted, the latter more throughout the entire margin 

 than in C. vestita var. rubro-oculata. A few refractive 

 granules, segments, or a small concave area at one end, 

 may remain in an otherwise gelatinized grain; this was 

 not noted in C. vestita var. rubro-oculata. 



The reaction with sulphuric acid begins immediately. 

 Complete gelatinization occurs in about 86 per cent of the 

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

 in 30 seconds; in about 98 per cent of the grains and 

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

 (Chart D 621.) 



The reaction with hydrochloric acid begins imme- 

 diately. Complete gelatinization occurs in about 9 per 

 cent of the entire number of grains and 42 per cent of 

 the total starch in 5 minutes; in about 18 per cent of 

 the grains and 71 per cent of the total starch in 15 

 minutes ; in about 22 per cent of the grains and 89 per 

 cent of the total starch in 30 minutes ; in about 32 per 

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

 45 minutes; in about 36 per cent of the grains and 94 

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

 D 632.) 



Fissures similar in character to those in C. vestita 

 var. rubro-oculata are formed which resemble this starch 

 in contour and homogeneous ref ractivity ; but later 

 irregular deep fissures proceed over the mesial region 



of such grains more often than in C. vestita var. rubro- 

 oculata. The characteristic grains of this species have 

 either a sinuous or a crenate margin and appear un- 

 evenly refractive when viewed from above, due prob- 

 ably to unequal density caused by the margin ; these 

 grains are also broader than the characteristic ones of 

 C. vestita var. rubro-oculata. Similar fissures form in 

 these grains to those noted for C. vestita var. rubro- 

 oculata. The border which is sharply defined by the 

 formation of these fissures in both types of grains is 

 much narrower than that found in C. vestita var. rubro- 

 oculata; in the first-named grains the mesial region is 

 broken into more refractive granules although in both 

 types these are less resistant than in C. vestita var. rubro- 

 oculata. At the completion of the experiment (60 min- 

 utes) more grains have undergone disintegration and 

 solution and many more are in the act of breaking down 

 than in C. vestita var. rubro-oculata; the narrow border 

 is also quite resistant especially at the proximal end, 

 though narrower and less resistant than in C. vestita var. 

 rubro-oculata. Some grains become completely gela- 

 tinized without previous disintegration at one or more 

 points, and are then much swollen and somewhat dis- 

 torted. All the grains are swollen during the reaction 

 as in C. vestita var. rubro-oculata, but more frequently 

 show distortion and partial disintegration. 



The reaction with potassium hydroxide begins imme- 

 diately. Complete gelatinization occurs in about 5 per 

 cent of the entire number of grains and 77 per cent of 

 the total starch in 5 minutes ; in about 6 per cent of the 

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

 in about 10 per cent of the grains and 85 per cent of the 

 total starch in 30 minutes ; in about 19 per cent of the 

 grains and 90 per cent of the total starch in 45 minutes ; 

 in about 19 per cent of the grains and 93 per cent of the 

 total starch in 60 minutes. (Chart D 633.) 



The hilum or lamellae are not visible, except in a 

 very few grains. Gelatinization begins all through the 

 interior of the grains which is divided into very fine 

 granules by many fine fissures, and part or all of the 

 marginal material is often separated from the rest by an 

 irregular fissure ; the capsule, however, is not broken until 

 later. As the granular starch gelatinizes the grain en- 

 larges and there is here also more frequent dissolution 

 of the capsule than in G. vestita var. rubro-oculata. The 

 gelatinized grains are not so large as in C. vestita var. 

 rubro-oculata, and are much more distorted. 



The reaction with sodium salicylate begins immedi- 

 ately. Complete gelatinization occurs in about 92 per 

 cent of the entire number of grains and 96 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 634.) 



The hilum and lamella? are not visible. A very nar- 

 row and not very refractive band is formed about the 

 margin before gelatinization begins. Gelatiuization be- 

 gins at one point on the margin and proceeds differently 

 from the same reaction in C. vestita var. rubro-oculata 

 by the invasion of the grain by large irregular fissures 

 and cracks, which separate off small and large pieces of 

 ungelatinized starch, which then gelatinize; when the 

 end of the grains opposite to that at which gelatinization 

 started is reached, the ungelatinized starch becomes very 

 extensively fissured, and quickly and widely separated 



