604 



STARCHES OP LILIACE^. 



PS CI PA I 

 ~ PC PS 



Curve of Reaction-Intensities of Starch of 

 Brodiaea congesta. 



When not fissured, the hilutn appears as a rather indistinct, largo, round spot at the large end 

 of the grain, usually in or near the median line, and eccentrically about one-third of the longi- 

 tudinal axis. Double or triple hila occur, which may be partly separated from one another by fis- 

 sures. The hilum is usually fissured, and the fissure may range from shallow and narrow to very 

 deep and wide. It may be a simple transverse or diagonal line, with or without a single or double 

 ciu-ve; or it may be 3-armed or 4-armed; or irregularly stellate; or ragged and irregular. 



The lamelUB, as a rule, are not very distinct, are coarse and regular, and vary in distinctness 

 in different grains. They follow closely the outline of the margin of the grain. Those near the distal 

 end and marginal portions are apt to be coarser and more 

 distinct than those near the hilum. The latter are ob- 

 scured in almost every case by fissures. There are about 

 8 to 12 lamellae on the larger grains. 



The grains vary in size from 2 to 36ju. The common 

 size is about 20jtt. 



Polariscopic Properties. — The figure is centric and 

 usually clear-cut and distinct. Occasionally one or more 

 of the lines may be broader and less sharp at the margin; 

 rarely one or two are bent or otherwise distorted. In 

 most cases the figure is very regular. 



The degree of polarization is fairly high. It is some- 

 times low or absent at the distal end and marginal parts 

 and varies also in different grains. It is not quite so high 

 as in B. peduncularis. 



With selenite the quadrants are usually clear-cut, 

 unequal in size, and regular or irregular in shape. The 

 colors are fairly pure. 



Iodine Reactions. — With 0.25 per cent Lugol's solu- 

 tion the grains are colored deeply a blue-violet; with 0.125 

 per cent solution they color fairly and the color deepens slowly. The reaction is about the same as 

 in the grains of B. peduncularis. After heating until the grains are completely gelatinized, the solu- 

 tion is colored lightly and the grains very deeply with iodine. The grains are much swollen, dis- 

 torted, and lobulated. After boiling for 2 minutes the solution is colored much more deeply, but 

 the grain-residues much less. With a very slight excess of iodine the capsules are colored a red- 

 violet; some of the capsules contain blue-reacting starch in the proximal end. 



Staining Reactions. — ^With gentian violet the grains begin to stain at once very lightly, and 

 after 30 minutes are fairly stained, but deeper than the grains of B. peduncularis. 



With safranin the grains begin to stain at once, but the color is very faint. After 30 minutes 

 they are lightly stained, slightly deeper than the grains of B. peduncularis. 



Temperature Reaction. — The temperature of gelatinization is 68.5° to 70° C, mean 69.25°. 



Effects of Various Reagents. — With chloral hydrate-iodine there is reaction in some of the smaller 

 grains in 30 seconds, and in half in 5 minutes. About three-fourths are darkened in 30 minutes, 

 and one-fifth are not affected even after an hour. The reaction is in all respects qualitatively the 

 same as that in the grains of B. peduncularis. 



Reaction with chromic acid begins in the small grains in 20 seconds, is general in 23^ minutes, and 

 complete in 5 minutes. It is qualitatively identical with the reaction in the starch of B. peduncularis. 



Reaction with pyrogallic add begins in some grains in a minute, is general in 4 minutes, and is 

 over in 30 minutes. None of the grains is ever fully gelatinized, but all reach about the same inter- 

 mediate stage. The reaction is qualitatively the same as that in the starch of B. peduncularis. 



The reaction with ferric chloride begins in some grains in 13^ minutes; about half are affected 

 in 5 minutes, and two-thirds are completely gelatinized in 10 minutes. The reaction is complete 

 in most of the grains in 30 minutes, and in all in an hour. It is qualitatively the same as that noted 

 in the grains of B. peduncularis. 



With Purdy's solution there is a reaction in some grains in 30 seconds, but only half show 

 signs of reaction in 50 minutes. No further change was noted after the lapse of 23^2 hours. None 

 of the grains are completely gelatinized. This reaction is qualitatively the same as that in the grains 

 of B. peduncularis. 



