680 



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



gelatinized and many are either undergoing disintegra- 

 tion or have passed into solution — a much larger per- 

 centage in each case than noted for 0. cardinalis. The 

 region of the facets is the most resistant, the capsule at 

 other parts frequently being either slit at many points 

 or completely dissolved. The most resistant grains are 

 the scattered larger globular and dome-shaped grains. 



The grains are swollen and generally, if not com- 

 pletely gelatinized, retain only a single lamella at .the 

 margin which is either profusely striated or broken down 

 into linear granules, the process having proceeded much 

 farther iu all the grains, with exception of the few scat- 

 tered grains above mentioned, in which progress is about 

 the same as in G. cardinalis. 



The reaction with potassium hydroxide begins im- 

 mediately. Complete gelatinization occurs in about 3 

 per cent of the entire number of grains and 13 per cent 

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

 the grains and 18 per cent of the total starch in 15 min- 

 utes; in about 16 per cent of the grains and 25 per cent 

 of the total starch in 30 minutes ; in about 22 per cent 

 of the grains and 30 per cent of the total starch in 45 

 minutes; in about 31 per cent of the grains and 37 per 

 cent of the total starch in 60 minutes.^ (Chart D 469.) 



The reaction with potassium iodide begins imme- 

 diately. Complete gelatinization occurs in about 4 per 

 cent of the entire number of grains and 8 per cent of the 

 total starch in 5 minutes; in about 9 per cent of the 

 entire number of grains and 21 per cent of the total 

 starch in 15 minutes; in about 20 per cent of the entire 

 number of grains and 50 per cent of the total starch in 

 30 minutes; in about 25 per cent of the grains and 58 

 per cent of the total starch in 45 minutes; in about 31 

 per cent of the grains and 65 per cent of the total starch 

 in 60 minutes. (Chart D 470.) 



The hilum is not so distinct as in G. cardinalis. 

 The lamella? are visible and in some grains are less in- 

 distinct than in G. cardinalis. Gelatinization begins at 

 the hilum, and the process is very similar to that noted in 

 G. cardinalis, except that the whole process is much more 

 rapid, and the fine stria? radiating from the hilum are 

 usually not distinctly seen until near the end when they 

 become very prominent; later the starch at the margin 

 is divided into a number of coarse granules which grad- 

 ually become more transparent and are finally gela- 

 tinized. There are many more completely gelatinized 

 grains than in G. cardinalis, and they are large and some- 

 what distorted, but have some of the form of the un- 

 treated grain. There are some grains noted here that 

 have a more quickly reacting outer layer as in G. 

 cardinalis. 



The reaction with potassium sulphocyanate begins 

 immediately. Complete gelatinization occurs in about 5 

 per cent of the entire number of grains and 18 per cent 

 of the total starch in 5 minutes ; in about 25 per cent of 

 the grains and 86 per cent of the total starch in 15 

 minutes; in about 61 per cent of the grains and 93 per 

 cent of the total starch in 30 minutes ; in about 64 per 

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

 45 minutes; in about 64 per cent of the grains and 97 

 per cent of total starch in 60 minutes. (Chart D 471.) 



The reaction with potassium sulphide begins in a few 

 grains immediately. Complete gelatinization occurs in 

 about 1 per cent of the entire number of grains and 3 



per cent of the total starch in 5 minutes ; slight advance 

 in 15 minutes; in about 3 per cent of the grains and 5 

 per cent of the total starch in 30 minutes; in about 4 

 per cent of the grains and 6 per cent of the total starch 

 in 45 minutes ; in about the same percentage of both the 

 grains and total starch in 60 minutes. (Chart D 472.) 



The reaction with sodium hydroxide begins imme- 

 diately. Complete gelatinization occurs in about 15 per 

 cent of the entire number of grains and 25 per cent of 

 the total starch in 5 minutes; in about 22 per cent of 

 the grains and 35 per cent of the total starch in 15 min- 

 utes ; in about 35 per cent of the grains and 50 per cent 

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

 of the grains and 63 per cent of the total starch in 45 

 minutes ; in about 50 per cent of the grains and 68 per 

 cent of the total starch in 60 minutes. (Chart D 473.) 



The hilum becomes somewhat less distinct than in 

 G. cardinalis, and the lamella? appear sometimes very 

 clearly as gelatinization progresses. Gelatinization be- 

 gins at the hilum, and the process is similar to that 

 described under G. cardinalis, except that the stria? radi- 

 ating from the hilum are not so distinct as in that starch, 

 nor are the granules which tend to persist in the interior 

 of the gelatinized grain so often seen. The gelatinized 

 grains are large and their walls are not so thick as those of 

 G. cardinalis; they are also somewhat more distorted. 



The reaction with sodium sulphide begins imme- 

 diately. Complete gelatinization occurs in about 3 per 

 cent of the entire number of grains and 8 per cent of the 

 total starch in 5 minutes; in about 10 per cent of the 

 grains and 18 per cent of the total starch in 15 minutes; 

 in about 24 per cent of the grains and 34 per cent of the 

 total starch in 30 minutes; in about 36 per cent of the 

 grains and 58 per cent of the total starch in 45 minutes; 

 in about 40 per cent of the grains and 70 per cent of the 

 total starch in 60 minutes. (Chart D 474.) 



The reaction with sodium salicylate begins imme- 

 diately. Complete gelatinization occurs in about 52 per 

 cent of the entire number of grains and 64 per cent of 

 the total starch in 5 minutes; in about 88 per cent of 

 the grains and 90 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 

 D475.) 



The hilum becomes distinct and a bubble is moder- 

 ately often formed there, not so often as in G. cardinalis, 

 and two lines are formed from the hilum to the corners 

 of the pressure facets. The lamella? are not visible. 

 Gelatinization begins at the hilum in the less resistant 

 grains and at the distal corners of the pressure facets 

 in the more resistant grains. In the first-named grains 

 gelatinization progresses in the same way as in G. car- 

 dinalis; in the second, the grain lengthens transversely 

 as the hilum and the fissures or canals connecting it with 

 the distal corners swell and lengthen. By this swelling 

 the grain is divided into two parts, distal and proximal, 

 of which the former is the first to be gelatinized. The 

 gelatinized grains are moderately large and somewhat 

 distorted, but retain much of their original form. 



The reaction with calcium nitrate begins immediately. 

 Complete gelatinization occurs in about 2 per cent of the 

 entire number of grains and 6 per cent of the total 

 si arch in 5 minutes ; in about 3 per cent of the grains and 

 10 per cent of the total starch in 15 minutes; in about 9 



