432 



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



in a narrow band at either side of the hilum when the 

 process advances from two ends. The starch is frequently 

 more resistant at one than the other side of the hilum. 



The completely gelatinized grains are swollen and 

 but little distorted. Some grains are only partially gela- 

 tinized, often containing either large refractive masses 

 or very refractive granules. Many grains are but little 

 affected by the reagent with the exception of swelling of 

 the hilum and enlargement of fissures present in the 

 untreated grain. 



The reaction with potassium sulphocyanate begins 

 in very few grains in 1 minute. Complete gelatinization 

 occurs in about 1 per cent of the entire number of grains 

 and in about 2.5 per cent of the total starch in 5 minutes ; 

 in about the same percentage of each in 15 minutes; in 

 about 2 per cent of the grains and 3 per cent of the total 

 starch in 45 minutes ; and in about 2.5 per cent of the 

 grains and 4 per cent of the total starch in 60 minutes. 

 (Chart D93.) A large percentage of the grains is 

 apparently unaffected. 



The hilum swells, but no bubble was detected at this 

 region. The untreated grain is sometimes penetrated by 

 a delicate fissure, in which case an enlargement of this 

 cleft is noted, but no marked refractivity. The lamellae 

 do not usually become more sharply defined, excepting 

 previous to their disorganization in a few grains. One 

 or two fissures may proceed from the hilum, and some- 

 times the hilum may be inlersected by a fissure. These 

 fissures are generally unbranched and delicate, but occas- 

 ionally they are sparingly branched and quite deep. 

 Gelatinization more frequently begins by a swelling of 

 the hilum and progression along the course of fissures, the 

 distal end being less resistant. The process may begin 

 almost simultaneously at both ends when the hilum is 

 either centric or but slightly eccentric, the most resistant 

 area then being a band at either side of the hilum. In 

 a few grains gelatinization may begin at a prominent 

 corner or at the distal end, and a deep fissure, which 

 at first has no connection with the hilum, may extend 

 inward from this gelatinized area. The mesial region 

 is often disorganized with the appearance of irregularly 

 arranged refractive granules, and the marginal region, 

 especially the proximal end and sides, into linearly 

 arranged refractive granules. In some grains deep fis- 

 sures may break the starch into moderately large refrac- 

 tive granules previous to gelatinization. 



The gelatinized grains are swollen and but slightly 

 to considerably distorted. Eefractive granules are found 

 in many of the grains, often linearly arranged at the 

 proximal end and sides nearby. Some of the gelatinized 

 grains bear a general resemblance to the untreated grain. 



The reaction with potassium sulphide begins in rare 

 grains in 1. minute. Complete gelatinization occurs in 

 less than 1 per cent of the entire number of grains and in 

 about 1 per cent of the total starch in 5 minutes; in 

 about 0.5 per cent of the grains and 1 per cent of the total 

 starch in 15 minutes; in 1 per cent of the grains and 

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

 same percentage of each in 45 minutes ; and in about the 

 same percentage of each in 60 minutes. (Chart D 94.) 

 A very few grains are fairly soon completely or almost 

 completely gelatinized, with but little additional effect, 



a peculiarity observed in all six of the Hsemanthuses 

 except H. puniceus. 



The hilum swells ; either one or two fissures leave the 

 hilum and proceed distalward, which may remain clean- 

 cut, but often become branched towards the distal end. 

 One lamella frequently becomes very distinct and serves 

 as a boundary between the mesial portion and a very 

 refractive border ; occasionally a few lamellae become dis- 

 tinct through the mesial portion between two obliquely 

 directed longitudinal fissures. The mesial portion of 

 the grain is usually disorganized with the appearance 

 of quite refractive irregularly arranged granules, and of 

 a narrow marginal border of very refractive, linearly 

 arranged granules. 



The gelatinized grain is much swollen, and when com- 

 pletely gelatinized is slightly distorted, but many are 

 gelatinized with the exception of either linear marginal 

 granules or a deeply striated, narrow marginal border. 



The reaction with sodium hydroxide begins in a few 

 grains in 1 minute. Complete gelatinization occurs in 

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

 in about 1 per cent of the total starch in 5 minutes; 

 in about 1 per cent of the grains and 2.5 per cent of the 

 total starch in 15 minutes; in about the same percentage 

 of each in 30 minutes ; in about the same percentage of 

 grains and a slight increase in the percentage of total 

 starch in 45 minutes ; and in about tlie same percentage 

 of grains and 3 per cent of the total starch in 60 min- 

 utes. ( Chart D 95.) The hilum swells very slowly, and 

 no bubble is detected at the point. Very gradually one 

 lamella situated at varying distances from the hilum 

 (frequently about 0.66 of the longitudinal axis), and 

 sometimes a few near the margin, may become more 

 distinct. Either one or two delicate fissures proceed 

 from the hilum which are usually clear-cut, but may 

 branch toward the distal end. The mesial region breaks 

 down into very refractive granules; a narrow marginal 

 border which may be entire or extend only around the 

 proximal end and sides is very resistant, it becoming very 

 refractive and profusely striated, finally breaking down 

 into very refractive granules, linearly arranged, before 

 gelatinization. The distal end is the first point of this 

 marginal border to become gelatinized, and when the fis- 

 sure is branched at this end the reaction may be com- 

 pleted at this point previous to that at the mesial margin. 

 The gelatinized grain is much more swollen. 



The reaction with sodium sulphide begins in rare 

 grains in 1 minute. Complete gelatiuization occurs in 

 about 1 per cent of the entire number of grains and 

 about 1.5 per cent of the total starch in 5 minutes; in 

 about the same percentage of each in 15 minutes and in 

 30 minutes ; in about the same percentage of grains and 

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

 the same percentage of each in 60 minutes. A very few 

 grains are quickly attacked by the reagent but apart from 

 this there is very little effect. (Chart D 96.) 



The reaction with sodium salicylate begins in 30 sec- 

 onds. Complete gelatinization occurs in about 68 per 

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

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

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

 15 minutes; in over 99 per cent of both grains and total 



