GENUS GLADIOLUS. 



717 



Qart No. 273. 



Curve of Reaction-Intensities of Starch of Gladiolus 

 primulinus. 



With selenite the quadrants are, as a rule, fairly well defined, regular in shape, and nearly equal 

 in size. The colors are fairly pure. 



Iodine Reactions. — With 0.25 per cent Lugol's solution the grains color a fairly deep violet; 

 with 0.125 per cent solution they color lightly and the color deepens slowly. The color is less than 

 that of the grains of G. hyzantinus. After heating in water until the grains are completely gelatin- 

 ized, the solution colors fairly and the grains deeply on the addition of iodine. After boiling for 2 

 minutes the solution colors deeply and the grain-residues 

 usually lightly. On addition of an excess of iodine the 

 capsules take on a red-violet color and many are seen 

 to retain some blue-reacting starch. 



Staining Reactions. — With gentian violet the grains 

 begin to stain very lightly in 2 minutes and in 30 min- 

 utes the color has not changed. It is lighter than that 

 of the grains of G. hyzantinus. 



With safranin the grains begin to stain lightly in a 

 minute and after 30 minutes the color has not changed. It 

 is distinctly lighter than that of the grains of G. hyzantinus. 



Temperature Reaction. — The temperature of gelatin- 

 ization is 80° to 82° C, mean 81°. 



Effects of Various Reagents. — ^With chloral hydrate- 

 iodine reaction begins in some grains in 30 seconds and 

 in most grains in 2 minutes. About half are gelatinized 

 in 10 minutes, two-thirds in an hour, and three-fourths 

 in 1^ hours. It is the same qualitatively as in the grains 

 of G. hyzantinus. 



The reaction with chromic add begins in 2 minutes 

 and is over in 5 minutes. It is the same qualitatively as that of the grains of G. hyzantinus. 



Reaction with pyrogallic acid begins slightly in a few grains in 2 minutes. In 15 minutes a few 

 of the grains are partially gelatinized, in 22 minutes all are partially gelatinized, and in 35 minutes 

 some are completely gelatinized. The reaction is the same qualitatively as that of the grains of 

 G. hyzantinus. 



With ferric chloride the reaction begins in a few grains in 13^ minutes and is over in 25 minutes. 

 It is qualitatively the same as that of the grains of G. hyzantinus. 



There is no reaction with Purdy's solution. 



STARCH OF GLADIOLUS CARDINALIS VAR. (BLUSHING BRIDE). 

 (Plate 69, figs. 411 and 412. Chart 274.) 



Histological Characteristics. — Inform the grains are simple, except a very few compounds, consist- 

 ing of two or three components which have become covered with two or three common lamellae. The 

 grains usually occur in aggregates of two or three grains of equal size, which are so firmly adherent 

 that few of them become separated; hence, grains with pressure facets are rare. The grains con- 

 stituting the aggregates are regular in outline, but varied in form in accordance with the number, 

 size, and arrangement of the grains. The conspicuous forms among the isolated grains are the ovoid 

 with much rounded ends, spherical, and rounded triangular; those among the aggregates are the 

 triangular, the elliptical, and the ovoid. The last is formed by one large grain having what appears to 

 be one or two very small grains inserted in the distal end. The forms of the component grains of 

 the aggregates are somewhat hemispherical with two or three or more facets at the distal end, and 

 hemispherical and sugar-loaf forms with one facet at the distal end. The grains are not flattened, 

 and in one aspect they appear spherical. 



The hilum is a fairly distinct, comparatively large, round spot, centric or eccentric about two- 

 fifths of the longitudinal axis and in the median line. It is never fissured. Rarely there are double 

 hila in a single component. Fissures, depressions, or lines may be seen which define the regions 

 of union of components of aggregates. 



The lamellos arc not distinct, and appear as regular, coarse rings which tend to follow the marginal 

 outline. They do not vary much in size and distinctness in different grains, nor in different parts 

 of the same grain. There are from 6 to 8 on the larger grains. 



