614 



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



Temperature Reactions. 



The temperature of gelatinization of the majority of 

 the grains is 52° to 53° C., and of all is 55.6° to 56° C, 

 mean 55.8° C. 



Comparison of the temperature reactions between L. 

 mart-agon album and L. temdfolium shows : 



The temperature of gelatinization is higher than 

 that of L. tenuifolium, 62° to 64° C., mean 63° C. 



Effects of Various Reagents. f 



The reaction with chloral hydrate begins in 30 sec- 

 onds. Complete gelatinization occurs in about 23 per 

 cent of the entire number of grains and 68 per cent of 

 the total starch in 5 minutes ; in about 80 per cent of the 

 grains and 97 per cent of the total starch in 15 minutes; 

 and in about 98 per cent of the grains and in more than 

 99 per cent of the total starch in 30 minutes. (Chart 

 D361.) 



The hilum becomes distinct, attended by the forma- 

 tion of a bubble in a majority of the grains. The lamella? 

 are usually not visible, but in some of the grains they are 

 moderately distinct. The grains become, more refractive 

 after the addition of the reagent, and the first part of the 

 grain to show this increased refractivity is a narrow strip 

 at the margin. Gelatinization begins at one or two 

 isolated points on the distal margin, and from these 

 points it extends around the margin, only the extreme 

 marginal material being affected. Gelatinization is 

 attended by much swelling and distortion of the capsule. 

 One or two groups of lamella; at the distal end are 

 separated from the rest and gelatinized. After this, 

 gelatinization progresses smoothly inward from all sides. 

 The last part of the grain to be gelatinized is that just 

 distal to the hilum. This is invaded by irregular fissures 

 and appears to be eroded at several points and is finally 

 completely gelatinized. The gelatinized grains are much 

 swollen, have rather thick capsules, and are very much 

 distorted. They bear no resemblance to the form of the 

 untreated grain. 



Comparison of the chloral-hydrate reactions between 

 L. martagon album and L. tenuifolium shows : 



A bubble is formed at the hilum in a small minority 

 of the grains instead of in a majority as in L. tenui- 

 folium, and the lamella? are never visible. The grain docs 

 not become so refractive after the addition of the re- 

 agent, and the strip of starch at the margin which first 

 shows this change is broader than a similar strip in 

 L. tenuifolium. Gelatinization begins at the distal end 

 and progresses around the margin more rapidly than in 

 the interior of the grain, but a wider layer of the marginal 

 material is gelatinized than in L. tenuifolium. Gela- 

 tinization is preceded by the formation of shallow depres- 

 sions in the margin and by a pitted appearance of the 

 surface of the ungelatinizcd starch. The last part of 

 the .grain to be gelatinized is, as in L. tenuifolium, the 

 portion just distal to the hilum, and this is often split 

 into two pieces which are gelatinized independently of one 

 another. This is never seen in L. tenuifolium. The 

 gelatinized grains are as much swollen and have as thick 

 capsules as in L. tenuifolium. They are even more dis- 

 torted than in that starch and bear no resemblance to the 

 form of the untreated grain. 



The reaction with chromic acid begins immediately. 

 Complete gelatinization occurs in about 77 per cent of 



the entire number of grains and 95 per cent of the total 

 starch in 3 minutes; in about 81 per cent of the grains 

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

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

 per cent of the total starch in 15 minutes. (Chart 

 D362.) 



The hilum becomes distinct in all the grains, attended 

 by the formation of a bubble in very few. The lamella? 

 are moderately distinct. The hilum begins to swell much 

 more rapidly toward the proximal than the distal end 

 of the grain. Two fissures extend from either side of 

 the hilum nearly to the distal margin. The starch in- 

 cluded between them is extensively fissured by a number 

 of fine branching fissures and is then rapidly gelatinized. 

 As the grain swells the residue of this starch forms a 

 refractive granular mass at the distal end which is often 

 gelatinized before dissolution of the grain. The portion 

 at the proximal end and sides forms a refractive homo- 

 geneous-looking band at the margin which is thinner at 

 the proximal end. It is finally dissolved at this point, 

 and solution proceeds toward the distal end ; the last part 

 to be dissolved being the thin capsule at the distal end. 



Comparison of the chromic-acid reactions between 

 L. martagon album and L. tenuifolium shows : 



There are as few grains in which a bubble is formed 

 at the hilum as in L. tenuifolium, and the lamella? are 

 more distinct than in that starch. Gelatinization pro- 

 ceeds in an essentially similar fashion. The differences 

 noted are that the fissures extending from the hilum on 

 either side toward the distal end are much shorter and 

 the material comprehended between them is more dis- 

 tinctly and somewhat more irregularly fissured, and the 

 granular residue at the distal end is much less distinctly 

 granular and is also more resistant, often being nearly the 

 last part of the grain to be dissolved. 



The reaction with pyrogallic acid begins immediately. 

 Complete gelatinization occurs in about 93 per cent of 

 the entire number of grains and in more than 99 per 

 cent of the total starch in 5 minutes. (Chart D 365.) 



The reaction with nitric acid begins immediately. 

 Complete gelatinization occurs in about 98 per cent of 

 the entire number of grains and 99 per cent of the total 

 starch in 15 seconds, and in 100 per cent of the grains 

 and total starch in 30 seconds. 



The reaction with sulphuric acid begins immediately. 

 Complete gelatinization occurs in about 88 per cent of the 

 entire number of grains and 96 per cent of the total 

 starch in 30 seconds, and in more than 99 per cent of 

 the grains and total starch in 45 seconds. 



The reaction with hydrochloric acid begins imme- 

 diately. Complete gelatinization occurs in about 95 per 

 cent of the entire number of grains and 98 per cent of 

 the total starch in 15 seconds, and in 100 per cent of the 

 grains and total starch in 30 seconds. 



The reaction with potassium hydroxide begins imme- 

 diately. Complete gelatinization occurs in more than 99 

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

 10 seconds, and in 100 per cent of the grains and total 

 starch in 15 seconds. 



The hilum becomes distinct in all the grains, unat- 

 tended by the formation of a bubble in any. The lamella? 

 are distinct. Gelatinization begins at the hilum which 

 swells more rapidly toward the proximal than toward 

 the distal end. Two fissures extend from either side of 



