746 



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



and deeper than in P. walllchii. After heating in water 

 until the grains are gelatinized and then adding 2 per 

 cent Lugol's solution, the grains become moderate to 

 deep blue, some with reddish tint, the depth is somewhat 

 more varied, with the mean a little lighter and not so 

 many of reddish tint as in both parents. If the prepara- 

 tion is boiled for 2 minutes and then treated with an 

 excess of 2 per cent Lugol's solution, the rare grain- 

 residues (less than in both parents) become light to 

 moderate blue, with a somewhat reddish tint, about the 

 same depth but less reddish than in P. grandifolius, and 

 little lighter but as reddish as in P. wallichii; most of 

 the capsules color a deep reddish-heliotrope, with a few 

 wine-red, a little deeper and less reddish than in P. gran- 

 difolius, less varied and the mean deeper and slightly 

 more reddish than in P. ivallichii. In the reactions with 

 iodine P. hybridus is closer to P. wallichii than to P. 

 grandifolius. 



Aniline Reactions. 



With gentian violet the grains immediately color very 

 lightly, and in 30 minutes they are moderate to deep 

 (value 60), slightly deeper than in P. grandifolius, but 

 considerably deeper than in P. ivallichii. A variation 

 in depth of color occurs as in both parents, the hilum 

 being more often deeply colored than in them. The 

 greater depth of color appears to be related to the lamella!, 

 which in the hybrid are coarser in most of the grains than 

 in the parents. 



With safranin the grains immediately color lightly, 

 and in 30 minutes they are moderately deep to deep 

 (value 65), deeper than in both parents. The grains 

 stain more deeply with this reagent than with gentian 

 violet as in both parents. The variations in depth of the 

 different parts of the grain are the same as for gentian 

 violet as in both parents. In the reactions with aniline 

 stains P. hybridus is closer to P. grandifolius than to 

 P. wallichii. 



Temperatuke Reactions. 



The temperature of gelatinization of the majority 

 of the grains is at 64° to 66° C, and of all but rare 

 resistant grains at 66 to 68° C, mean 67° C. The 

 proximal end and sides nearby are not so resistant as in 

 P. grandifolius, and about as in P. wallichii. The tem- 

 perature of gelatinization of P. hybridus is less than that 

 of either parent, and is closer to that of P. wallichii. 



Effects of Various Reagents. 



The reaction with chloral hydrate begins in a few 

 grains immediately. Complete gelatinization occurs in 

 about 23 per cent of the entire number of grains and 21 

 per cent of the total starch in 5 minutes; in about 36 

 per cent of the grains and 44 per cent of the total starch 

 in 15 minutes; in about 52 per cent of the grains and 

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

 56 per cent of the grains and 66 per cent of the total 

 starch in 45 minutes; in about 60 per cent of the grains 

 and 70 per cent of the total starch in 60 minutes. ( Chart 

 D574.) 



The hilum becomes as distinct as in P. grandifolius, 

 rarely a bubble is formed there, and there is the same 

 formation of lines or fissures and wrinkles in the capsule 

 as noted in the parents. The lamella? become as distinct 

 as in P. grandifolius, and a refractive band about the 



margin is quickly formed as in both parents. Gelatiniza- 

 tion usually begins at the distal end, then at the proximal 

 end as in P. grandifolius, though there are some grains 

 in which it begins at the proximal end as in P. wallichii. 

 The progress of gelatinization is the same as noted under 

 P. grandifolius. The gelatinized grains are very large 

 and are distorted as in P. grandifolius, and do not retain 

 much of the form of the untreated grain. In this reaction 

 P. hybridus qualitatively shows a closer relationship to 

 P. grandifolius than to P. wallichii. 



The reaction with chromic acid begins immediately. 

 Complete gelatinization occurs in about 3 per cent of the 

 entire number of grains and 44 per cent of the total 

 starch in 5 minutes; in about 34 per cent of the grains 

 and 87 per cent of the total starch in 15 minutes ; in about 

 98 per cent of the grains and over 99 per cent of the total 

 starch in 30 minutes. (Chart D 575.) 



The hilum, as in P. grandifolius, is distinct, as are also 

 the lamella?, and the lamella? are obscured and later ap- 

 pear as rows of granules. The refractive band noted in 

 the parents is also seen here. Gelatinization, as in the 

 parents, begins at the hilum. The method of gelatiniza- 

 tion in the majority of grains is that noted under P. 

 grandifolius, although in some it is the same as in 

 P. wallichii. In this reaction P. hybridus shows a closer 

 relationship to P. grandifolius than to P. wallichii. 



The reaction with pyrogallic acid begins in a few 

 grains immediately. Complete gelatinization only occurs 

 in a few grains, less than 0.5 per cent of the entire num- 

 ber of grains, and 8 per cent of the total starch, in 5 

 minutes ; in about 12 per cent of the grains and 62 per 

 cent of the total starch in 15 minutes; in about 23 per 

 cent of the grains and 70 per cent of the total starch in 

 30 minutes; in about 36 per cent of the grains and 77 

 per cent of the total starch in 45 minutes; in about 44 

 per cent of the grains and 84 per cent of the total starch 

 in 60 minutes. (Chart D 576.) 



The reaction with nitric acid begins immediately. 

 Complete gelatinization occurs in about 44 per cent of 

 the entire number of grains and 78 per cent of tile total 

 starch in 1 minute; in about S7 per cent of the grains 

 and 99 per cent of the total starch in 5 minutes ; in about 

 94 per cent of the grains and 99 per cent of the total 

 starch in 10 minutes; in about 99 per cent of the grains 

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

 (Chart D 577.) 



The hilum swells, and a bubble, which enlarges often 

 to considerable size and may be quite persistent, is more 

 frequent than in both parents. Gelatinization begins and 

 proceeds as in both parents. The minute steps and the 

 most resistant starch more closely adhere to that noted 

 for P. grandifolius than P. ■wallichii. The gelatinized 

 grains are swollen and distorted, about as in P. grandi- 

 folius; less than in P. wallichii. These reactions are 

 closer to P. grandifolius than to the other parent. 



The reaction with sulphuric acid begins immediately. 

 Complete gelatinization occurs in about 75 per cent of 

 the grains and 92 per cent of the total starch in 1 minute ; 

 in about 98 per cent of the grains and 99 per cent of the 

 total starch in 2 minutes ; complete gelatinization of all 

 the grains in 3 minutes. (Chart D 578.) 



The reaction with hydrochloric acid begins imme- 

 diately. Complete gelatinization occurs in about 92 per 



