864 



STAHCHES OF HELLEBORACE^. 



the grains is rather irregular owing to pressure. The conspicuous forms are round, oval and ovoid, 

 and dome-shaped to hemispherical; also low triangular with rounded base, irregular lenticular, 

 polygonal, and various indefinite forms. 



The hilutn is often not visible, and when seen it is round or oval, and not very refractive, and 

 appears to be more or less eccentric. There is no fissuration at the hilum, but sometimes there is a 

 depression passing through the center of the grain. 



The lameUce can not be distinguished. 



The grains vary in size; the smaller are 1 by 1ft; the larger are 12 by 12/i or 8 by lO/i in length 

 and breadth. The common size is 8 by 8m. 



Polariscopic Properties. — The figure is usually more or less eccentric. The lines are rather 

 thick and usually straight and expanded towards the margin. In some grains they are bent. 



The degree of polarization, is low. It varies somewhat in different grains and sometimes in 

 the same aspect of a grain. 



With selenite the quadrants are generally fairly well defined, slightly irregular in shape, and 

 unequal in size. The colors in a few are fairly bright and pure, while in others they are very dull. 



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

 tion the grains all color a deep blue-violet; with 0.125 

 per cent solution they color fairly, and the color deepens 

 rapidly. After heating in water until the grains are com- 

 pletely gelatinized, the solution colors fairly and the gel- 

 atinized grains very deeply on the addition of iodine. 

 After boiling for 2 minutes the solution colors very deeply 

 and the grain-residues lightly. The capsules all color a 

 violet on the addition of an excess of iodine. 



Staining Reactions. — With gentian violet and with saf- 

 ranin the grains begin to stain very lightly in a minute 

 and in 30 minutes they are very lightly stained. 



Temperature Reaction. — The temperature of gelatin- 

 ization is 59° to 60° C, mean 59.5°. 



Effects of Varums Reagents. — With chloral hydrate- 

 iodine the reaction begins in a few seconds and is over 

 in a minute. The distal end darkens and the grain at 

 this point becomes gelatinized and swells. The process 

 then spreads upward and inward rapidly over the whole 

 grain, and as it nears the hilum a bubble appears here 



which increases in size, then shrinks, and disappears as the rest of the starch at the proximal end 

 darkens and swells. The gelatinized grains are not very large and retain much of their original 

 form. They have a Ught, round space in the center surrounded by a thick, dark margin. 



The reaction with chromic add begins at once and is over in 10 seconds. It is so rapid that the 

 separate steps can not be determined. 



The reaction with pyrogallic acid begins in a few seconds and is over in a minute. The starch 

 about the hilum begins to gelatinize, and this is followed by the gelatinization and swelling of all of 

 the grain. Striae do not appear, or if they do they are so fine that they can not be made out. The 

 gelatinized grains are large and thin-walled and the walls are somewhat folded and wrinkled. The 

 gelatinized grains retain some of the original form. 



The reaction with ferric chloride begins in 15 seconds and is over in 33^ minutes. The reaction 

 b^ins at the distal end, which becomes gelatinous and swells out irregularly. The process then 

 spreads upward and inward over the rest of the grain until only the proximal end is ungelatinized. 

 This part is fissured m several places and divided into two or three pieces of unequal size which 

 gelatinize. The gelatmized grain is large and distorted, and the capsule is much wrinkled and 

 folded. 



Reaction with Purdy's solution begins at once and is over in 25 seconds. The several steps of 

 the reaction can not be determined, but it appears to consist of the gelatinization of the starch 

 surrounding the hilum and the general swelling of the grain. The more resistant starch forms a 

 fairly thick homogeneous band at the margin, and this grows thinner and transparent. The gelat- 

 inized grains are large and somewhat distorted. 



Curve 



of Reaction-Intensities of Starch of Cimicifuga 

 racemosa. 



