GENUS GLADIOLUS. 



719 



Chart No. 275. 



PC PS 

 5 



The hiliim is a fairly distinct, comparatively large round spot, centric, or eccentric to about 

 two-fifths or more of the longitudinal axis of the grain, and in the median line. The hilum is never 

 fissured and no multiple liila were observed. 



The lamellae are invisible. 



The grains vary in size from 2 to \2ix. The common size is 8yu. 



Polariscopic Properlies. The figure is centric or slightly eccentric, distinct, and clear-cut. Its 

 lines are not bent or distorted in any way and tend to be placed at equal distances from one another. 



The degree of polarization is fairly high. It does not vary much in different grains, or in dif- 

 ferent aspects of the same grain, or in different parts of the same aspect of a given grain. It is on 

 the whole not quite so high as in the grains of G. hyzantinus. 



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

 size. The colors are fairh^ 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, but the color soon deepens. It is of the same inten- 

 sity as that of the grains of G. byzantinus. After heating in water until the grains are completely 

 gelatinized, both the solution and the grains color fairly 

 on the addition of iodine. After boiling for 2 minutes 

 the solution colors deeply and the grain-residues rather 

 lightly. All the capsules color violet when an excess 

 of iodine is added and most of them retain some blue- 

 reacting starch. 



Staining Reactions. With gentian violet the grains 

 begin to stain verj- lightly in a minute and in 30 minutes 

 they are but very lightly stained. The color is slightly 

 less than that of G. byzantinus. 



With safranin the grains begin to stain lightly at 

 once and in 30 minutes they are fairly colored. The color 

 is slightly less than that of the grains of G. hyzantinus. 



Temperature Reaction. The temperature of gelatin- 

 ization is 76 to 77 C, mean 76.5. 



Effects of Various Reagents. With chloral hydrate- 

 iodine reaction begins in many grains in a minute. Nearly 

 all are gelatinized in 8 minutes and all in 15 minutes. The 

 reaction is qualitatively the same as that of the grains of 

 G. byzantinus. 



The reaction wnth chromic acid begins in 30 seconds and is over in 33^ minutes. It is the same 

 qualitatively as that of the grains of G. byzantinus. 



Reaction with pyrogallic acid begins in a minute. All are partially gelatinized in 3 minutes and 

 completely in 15 minutes. The reaction is qualitatively the same as that of the grains of G. byzantinus. 



With ferric chloride the reaction begins in a few grains in a minute. About one-half are gelat- 

 inized in 4 minutes and all in 23 minutes. The reaction is qualitatively the same as that of the 

 grains of G. byzantinus. 



The reaction with Purdy's solution begins in a few grains in a minute. In 20 minutes about 

 half the grains are partially and the others beginning to be gelatinized. The reaction is qualita- 

 tively the same as that of the grains of G. byzantinus. 



Curve of Reaction-Intensities of Starch of Gladiolus 

 fioribundus. 



Differentiation of Certain Starches of the Genus Gladiolus. 



Histological Chahacteristics. 

 Conspicuous Forms. 



G. hyzanlinus: Simple, many small aggregates of 2, 3, or 

 more components; nearly all isolated grains have 

 pressure facets; surface regular but varied owing 

 to facets. Hemispherical with a 2-, 3-, or 4-faceted 

 base. 



G. primulinus: Essentially the same as in G. byzanti- 

 nus, except in absence of aggregates and the con- 

 spicuous forms are polygonal, which are much 

 varied. 



Histological Characteristics. Continued. 

 Conspicuous Forms. Continued. 



G. cardinalis var. (Blushing Bride): Essentially the same 

 as in G. hyzanlinus, but the conspicuous forms 

 are ovoid with much rounded ends, spherical, and 

 rounded triangular. 



G. florihundus: Essentially tlie same as in G. byzantinus, 

 except in absence of aggregates and that the con- 

 spicuous forms are spherical or almost spherical 

 with one small facet at distal end, and somewhat 

 quadrilater.<il with 3 basal facets and rounded side. 



