672 



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



in length and breadth. The common sizes are 26 by 22p. 

 and 30 by 24/*. I. pursind is somewhat closer in size to 

 I. sindjarensis than to /. persica var. purpurea. The 

 common sizes are in one case as long and 4/n broader, 

 and in the other 4ju longer and the same breadth, as the 

 common sizes of I. sindjarensis; and are, respectively, 6/x 

 shorter and 4/x narrower, and 2ft, shorter and 2/t nar- 

 rower, than the common sizes of /. persica var. purpurea. 



POLABISCOPIC PBOPEBTTES. 



The figure is as distinct and nearly as well defined aa 

 in /. sindjarensis, and much better denned than in I. per- 

 sica var. purpurea. The lines, as in I. persica var. pur- 

 purea, cross at a right angle or at an acute angle which 

 varies considerably in different grains. They are as 

 often bent as in I. persica var. purpurea, but somewhat 

 less often bisected or subdivided into 3 or 4 divisions. 



The degree of polarization varies from moderate to 

 high (value 65), 5 units lower than I. persica var. 

 purpurea and 10 units lower than /. sindjarensis. There 

 is some variation in a given aspect of an individual grain 

 as in I. persica var. purpurea. 



With selenite the quadrants are nearly as clear-cut 

 as in /. sindjarensis, and more so than in /. persica var. 

 purpurea. The quadrants as in I. persica var. purpurea 

 are unequal in size and irregular in shape. The colors 

 are not so pure as in either parent, but are closer to those 

 of the grains of I. persica var. purpurea than of the grains 

 of I. sindjarensis. 



In the character of the figure, the degree of polariza- 

 tion, and the appearances with selenite, I. pursind shows 

 a closer relationship to I. persica var. purpurea than to 

 I. sindjarensis. 



IODINE REACTIONS. 



With 0.25 per cent Lugol's solution the grains all 

 color a moderate blue- violet (value 50), the same as in 

 /. sindjarensis and 5 units lower than in /. persica var. 

 purpurea. With 0.125 per cent Lugol's solution the 

 grains are colored a light blue-violet, the same as in 

 7. sindjarensis and less than in I. persica var. purpurea. 

 After heating in water until all the grains are completely 

 gelatinized and then treating with a 2 per cent Lugol's 

 solution, the gelatinized grains are colored a light or a 

 light to moderate indigo, and the solution a very deep 

 indigo, as in I. sindjarensis. If the preparation is boiled 

 for 2 minutes and then treated with a 2 per cent Lugol's 

 solution most of the grain-residues are not colored except 

 the capsule, and the capsules are colored a reddish violet, 

 and the solution a very deep indigo, as in 7. sindjarensis. 

 Qualitatively and quantitatively the reactions with iodine 

 show a closer relationship to /. sindjarensis than to J. 

 persica var. purpurea. 



ANILINE REACTIONS. 



With gentian violet the grains, as in 7. sindjarensis, 

 stain very lightly at once, and in 30 minutes they are 

 light to moderately colored (value 40), 5 units less than 

 in 7. persica var. purpurea, and 2 units less than in 7. 

 sindjarensis. There is a much greater proportion of 

 grains light to moderately stained than in 7. persica var. 

 purpurea, and somewhat greater than in 7. sindjarensis. 



With safranin, the grains, as in the parents, stain 

 very lightly at once, and in 30 minutes they are moder- 

 ately colored (value 45), 5 units less than in 7. persica 

 var. purpurea, and 2 units less than in 7. sindjarensis. 



In the reactions with aniline stains 7. pursind shows a 

 closer relationship to 7. sindjarensis than to 7. persica 

 var. purpurea. 



TEMPERATURE REACTIONS. 



The temperature of gelatinization of the majority 

 of the grains is 64.5 to 66 C., and of all is 68 to 

 70 C., mean 69 C. The temperature of gelatinization 

 of 7. pursind is the same as that of 7. persica var. pur- 

 purea, and 2.5 C. higher than that of 7. sindjarensis. 



EFFECTS OF VARIOUS REAGENTS. 



The reaction with chloral hydrate begins in 1 minute. 

 Complete gelatinization occurs in about 6 per cent of the 

 entire number of grains and 10 per cent of the total 

 starch in 5 minutes; in about 12 per cent of the grains 

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

 about 21 per cent of the grains and 28 per cent of the 

 total starch in 30 minutes; in about 33 per cent of the 

 grains and 36 per cent of the total starch in 45 minutes; 

 little if any further advance in 60 minutes. (Chart 

 D442.) 



The hilum is as distinct as in 7. persica var. pur- 

 purea, and a bubble is nearly as often formed there as 

 in that starch. The lamellae as in I. persica var. pur- 

 purea are at first indistinct but later become distinct; 

 and the grain becomes refractive during the reaction as in 

 7. persica var. purpurea. Gelatinization begins at the 

 distal margin, usually at small cracks or fissures in the 

 margin as in 7. persica var. purpurea, but sometimes in 

 the elongated forms at the distal corners as in 7. sind- 

 jarensis, and the progress of gelatinization is distinctly 

 closer to that described under 7. persica var. purpurea, 

 although there seems to be some tendency for the surface 

 starch to be less resistant than that of the interior as in 7. 

 sindjarensis. The gelatinized grains have thicker cap- 

 sules than in 7. persica var. purpurea, but not so thick as 

 in 7. sindjarensis, but they are as distorted and bear as 

 little resemblance to the form of the untreated grain as 

 in that starch. In this reaction 7. pursind shows qualita- 

 tively a closer relationship to 7. persica var. purpurea 

 than to 7. sindjarensis. 



The reaction with chromic acid begins in 1 minute. 

 Complete gelatinization occurs in about 2 per cent of 

 the entire number of grains and 12 per cent of the total 

 starch in 5 minutes; in about 28 per cent of the grains 

 and 85 per cent of the total starch in 15 minutes; in 

 about 43 per cent of the grains and 95 per cent of the 

 total starch in 30 minutes ; in about 54 per cent of the 

 grains and 92 per cent of the total starch in 45 minutes ; 

 in about 74 per cent of the grains and 98 per cent of the 

 total starch in 60 minutes. (Chart D 443.) 



The reaction with pyrogallic acid begins in 30 min- 

 utes. Complete gelatinization occurs in about 25 per 

 cent of the entire number of grains and 82 per cent of 

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

 the grains and 99 per cent of the total starch in 15 

 minutes; in about 95 per cent of the grains and in more 

 than 99 per cent of the total starch in 30 minutes. 

 (Chart D444.) 



The reaction with nitric acid begins immediately. 

 Complete gelatinization occurs in about 39 per cent of 

 the entire number of grains and 87 per cent of the total 

 starch in 5 minutes; in about 71 per cent of the grains 

 and 98 per cent of the total starch in 15 minutes; in 



