744 



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



and are much more frequently present, as well as more 

 branched, than in P. grandifolius. The different regions 

 are disorganized as in P. grandifolius, but the quite re- 

 fractive areas are much less frequently observed. The 

 reaction begins at the proximal end in the majority of 

 grains, but instead of advancing along the narrow refrac- 

 tive border of the sides, as so often observed in P. grandi- 

 folius, the disorganization occurs also in the mesial 

 portion of the proximal end. The distal corners are 

 more frequently gelatinized with distortion than in P. 

 grandifolius. 



The gelatinized grains are much swollen and dis- 

 torted, more of the latter than in P. grandifolius. The 

 distal margin is more frequently thrown into irregular 

 folds, and the proximal end more frequently elongated 

 and irregularly distorted than in P. grandifolius. The 

 gelatinized grains do not resemble the untreated grains 

 as in P. grandifolius. 



The reaction with sodium sulphide begins imme- 

 diately. Complete gelatinization occurs in about 67 per 

 cent of the entire number of grains and 92 per cent of 

 the total starch in 2 minutes ; in about 82 per cent of the 

 grains and 96 per cent of the total starch in 5 minutes; 

 in about 96 per cent of the grains and 99 per cent of the 

 total starch in 15 minutes. (Chart D 585.) 



A bubble appears at the hilum which expands to con- 

 siderable size as in P. grandifolius. The lamclke become 

 sharply defined and striated as in P. grandifolius. 

 Usually 2 fissures appear which are not deep, but are 

 much branched, especially towards the distal corners, 

 and are much more frequently present than in P. grandi- 

 folius. The starch in both the mesial and marginal re- 

 gions is disorganized without the formation of refractive 

 granules as in P. grandifolius. The process more fre- 

 quently begins as in P. grandifolius, with the exception 

 that all the starch across the proximal end gelatinizes, 

 accompanied by irregular distortion at this end instead 

 of a ruffling of the narrow lateral border, the latter being 

 usually noted in P. grandifolius. The distal corners and 

 margins are quickly gelatinized, accompanied by much 

 distortion, more distortion than in P. grandifolius. In 

 a few grains the narrow, refractive, proximal and lateral 

 borders are the most resistant — fewer grains of this 

 nature than in P. grandifolius, but they gelatinize in a 

 similar manner. The reaction is so rapid that no further 

 minute differences between the species can be determined. 

 The gelatinized grains are much swollen and irregularly 

 distorted, often with the proximal end much extended and 

 irregularly twisted, with more distortion and more exten- 

 sion at the proximal end than in P. grandifolius. 



The reaction with sodium salicylate begins imme- 

 diately. Complete gelatinization occurs in about 45 per 

 cent of the grains and 54 per cent of the total starch in 

 5 minutes; in about 94 per cent of the grains and 97 per 

 cent of the total starch in 15 minutes ; in over 99 per cent 

 of both the entire number of grains and total starch in 

 30 minutes. (Chart D 586.) 



The hilum becomes more distinct than in P. grandi- 

 folius, and a small bubble is more often formed there; 

 the folds or wrinkles in the capsule extending from the 

 hilum to the distal margin noted in P. grandifolius are 

 also present here. The lamellre are more distinct at first 

 than in P. grandifolhis and later become indistinct as 

 in that starch. A refractive band (less distinct than 



in P. grandifolius) is formed quickly about the margin 

 of the grain, and it recedes as gelatinization progresses. 

 Gelatinization unlike that of the grains of P. grandifolius 

 begins usually at the proximal end, and this is followed 

 by gelatinization of the corners of the distal margin, and 

 then of the whole distal end. Gelatinization progresses 

 smoothly from its initial points, and more rapidly from 

 the proximal than from the distal end, but the marginal 

 starch, differing from that in the grains of P. grandi- 

 folius, is less resistant than the central portion, the 

 most resistant part of which is usually found midway 

 between the hilum and the distal margin, or just at the 

 distal end, in any case nearer to the distal end than in 

 P. grandifolius. The gelatinized grains are very large 

 and much distorted and do not retain as much of the 

 form of the untreated grain as do those of P. grandifolius. 



The reaction with calcium nitrate begins immediately. 

 Complete gelatinization occurs in about 61 per cent of 

 the entire number of grains and 83 per cent of the total 

 starch in 5 minutes; in about 94 per cent of the grains 

 and over 99 per cent of the total starch in 15 minutes; 

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

 of the total starch in 30 minutes. (Chart D 587.) 



The reaction with uranium nitrate begins in a few 

 grains immediately. Complete gelatinization occurs in 

 about 63 per cent of the entire number of grains and 

 90 per cent of the total starch in 5 minutes ; in about 78 

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

 in 15 minutes; in about 93 per cent of the grains and 

 over 99 per cent of the total starch in 30 minutes ; little 

 if any further change occurs in 45 and 60 minutes. 

 (Chart D588.) 



The reaction with strontium nitrate begins imme- 

 diately. Complete gelatinization occurs in about 83 per 

 cent of the entire number of grains and 91 per cent of 

 the total starch in 2 minutes ; in about 99 per cent of the 

 grains and over 99 per cent of the total starch in 5 min- 

 utes; in 100 per cent of both the grains and total starch 

 in 9 minutes. (Chart D 589.) 



The reaction with cobalt nitrate begins in a few 

 grains in 1 minute. Complete gelatinization occurs in 

 about 7 per cent of the entire number of grains and 48 

 per cent of the total starch in 5 minutes; in about 31 

 per cent of the grains and 78 per cent of the total starch 

 in 15 minutes; in about 45 per cent of the grains and 87 

 per cent of the total starch in 30 minutes; in about 55 

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

 in 45 minutes; in about 63 per cent of the grains and 



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

 D 590.) 



The reaction with copper nitrate begins immediately. 

 Complete gelatinization occurs in about 86 per cent of the 

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

 starch in 5 minutes; in over 99 per cent of both the 

 grains and total starch in 10 minutes. (Chart D 591.) 



The reaction with cupric chloride begins in a few 

 grains immediately. Complete gelatinization occurs in 

 about 39 per cent of the entire number of grains and 

 82 per cent of the total starch in 5 minutes ; in about 63 

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

 in 15 minutes; in about 81 per cent of the grains and 



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

 89 per cent of the grains and 98 per cent of the total 



