696 



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



Form. — No compound grains or aggregates, such as 

 occur in B. single crimson scarlet, are seen in B. soco- 

 trana. The grains are not so often irregular as in B. 

 single crimson scarlet, but the irregularities are usually 

 more marked. The irregularities are due to the same 

 causes as in B. single cri??ison scarlet, and also very 

 commonly to: (1) 1 to 3 large or small, rounded or 

 pointed protuberances from the proximal end or sides. 

 The grains are much more elongated, and there are very 

 few of the round forms, common in B. single crimson 

 scarlet'. 



The htium is somewhat distinct and somewhat more 

 often fissured. The fissures have the same forms as in 

 B. single crimson scarlet, and in addition: (1) A some- 

 what branched Y form; (2) a flying-bird form. The 

 hilum is usually eccentric 0.18 of the longitudinal axis, 

 which is 0.07 more eccentric than in B. single crimson 

 scarlet. 



The lamella are somewhat more distinct and less 

 regular than in B. single crimson scarlet. There is 

 never a very coarse, refractive lamella near the hilum, 

 or one outlining the primary starch in the grain which 

 consists of both primary and secondary starch deposits. 

 Otherwise the characteristics and the arrangement are 

 the same. 



In size the grains are larger, the larger grains being 

 22/A longer and 6u broader, and the common sizes 12^ 

 longer and 1/* broader and 12/i longer and 7/*. broader 

 respectively than the corresponding common forms of 

 B. single crimson scarlet. 



Polabiscopic Properties. 



The figure is distinct and usually well denned. The 

 lines are usually thin, but may be thick especially near 

 the margin. They cross at an acute angle which does 

 not vary greatly in size in the different grains. They are 

 sometimes considerably bent, but usually are not bent, 

 and are often bisected or even divided into 3 or 4 lines 

 near the margin. The figure sometimes has the form of 

 a conjugate hyperbola. 



The degree of polarization varies from moderately 

 high to high (value 60). There is very little variation 

 in a given aspect of the individual grains. 



With selenit'e the quadrants are usually clear-cut, but 

 in a moderate number of grains they are not. They 

 are unequal in size and usually regular but sometimes 

 very irregular in shape. The colors are usually pure, 

 except for a few, which have a greenish tinge. 



Comparison of the polariscopic properties between 

 B. socotrana and B. single crimson scarlet shows: 



The figure is as distinct and better defined than in 

 B. single crimson scarlet. The lines are always thin 

 and not so often or so much bent, or bisected, or other- 

 wise subdivided, as in B. single crimson scarlet. Figures 

 in the form of a conjugate hyperbola are never seen. 



The degree of polarization varies from moderately 

 high to high (value 60), the same as in B. single crimson 

 scarlet. 



With selenite the quadrants are more often well 

 defined, more unequal in size, and less often irregular in 

 6hape. The colors are usually pure and about the same 

 number of grains have a greenish tinge as in B. single 

 crimson scarlet. 



Iodine Reactions. 



With 0.25 per cent Lugol's solution the grains all 

 color a moderate blue-violet (value 45). The color 

 deepens rapidly until it is very deep and has assumed 

 more of a bluish tint. With 0.125 per cent Lugol's solu- 

 tion, the grains all color a light violet tinged with blue, 

 and the color deepens with moderate rapidity until it is 

 deep and has assumed more of a bluish tint. After heat- 

 ing in water until the grains are all gelatinized, the gela- 

 tinized grains all color a deep indigo, and the solution 

 a moderate to deep indigo. If the preparation is boiled 

 for 2 minutes and then treated with an excess of a 2 per 

 cent Lugol's solution, the grain-residues are usually only 

 colored in the capsules, but a few are colored a moderate 

 indigo; the capsules are all colored a moderate violet; 

 and the solution a very deep indigo. 



Comparison of the iodine reactions between B. soco- 

 trana and B. single crimson scarlet shows : 



With 0.25 per cent Lugol's solution the grains all 

 color a light to moderate violet tinged with blue (value 

 30), 15 units less than in B. single crimson scarlet. 

 With 0.125 per cent Lugol's solution the grains are 

 colored a very light violet, much less than in B. single 

 crimson scarlet. After heating in water until all the 

 grains are completely gelatinized, the grains are colored 

 less and the solution more than in B. single crimson scar- 

 let. If the preparation is boiled for 2 minutes and then 

 treated with an excess of 2 per cent Lugol's solution, all 

 the grain-residues are more colored, the capsules more 

 and the solution somewhat less deeply colored, than in 

 B. single crimson scarlet. 



Aniune Reactions. 



With gentian violet the grains all color very lightly at 

 once, and in half an hour they are light to moderately 

 colored (value 45), most of the grains are colored moder- 

 ately, a few are light to moderate, and a few moderate 

 to high. 



With safranin the grains all color very lightly at 

 once, and in half an hour they are moderately to deeply 

 colored (value 60). Most of the grains are moderately 

 to deeply colored — a few moderately, and a few deeply 

 colored. 



Comparison of the aniline reactions between B. soco- 

 trana and B. single crimson scarlet shows : 



With gentian violet the grains color light to moder- 

 ately (value 35), 10 units less than in B. single crimson 

 scarlet. There is a wider variation in the depth of color 

 of different grains than in B. single crimson scarlet. 



With safranin the grains color moderately (value 55), 

 5 units less than in B. single crimson scarlet. There 

 is a wider variation in color in the different grains than 

 in B. single crimson scarlet. 



Temperature Reactions. 



The temperature of gelatinization of the majority of 

 the grains is 67° to 68.5° C, and of all 70° to 72° C, 

 mean 71° C. 



Comparisons of the temperature reactions between B. 

 socotrana and B. single crimson scarlet shows : 



The temperature of gelatinization is 81° to 81.8° C, 

 mean 81.4° C, which is 10.4° C. higher than that of 

 B. single crimson scarlet. 



