400 



STARCHES OF LEQUMINOSiB. 



Some of the nearly round grains have a small, indistinct, central hilum. In the few unfissured 

 grains there may be seen sometimes a number of faintly refractive granules grouped together in a 

 central non-lamellated space, but they are too indistinct to admit of their exact number or shape 

 being determined. 



The lamella are fairly distinct, usually rather coarse continuous bands which follow quite 

 regularly the outline of the grain. They are less coarse near the margin than near the central part. 

 There are 12 to 14 on the larger grains. 



The grains vary in size from the smaller, which are G by &n, to the larger, which are 50 by 44;i, 

 in length and breadth. The common size is 34 by 24;u in length and breadth. 



Polariscopic Properties. — The Jigure is centric or slightly eccentric, generally in the form of a 

 cross; in a few grains it is of the bean type. The lines 

 are broad and rarely clear-cut, tending to broaden near 

 the margin of the grain. A large dark area is commonly 

 observed at the point of intersection. 



The degree of polarization is low to fairly high, but 

 usually fairly high. A large part of the central area of 

 many grains, sometimes all except small marginal parts, 

 does not polarize. The degree of polarization does not 

 vary much in different aspects of the same grain. 



With selenite the quadrants, as a rule, consist of sev- 

 eral portions of the same color grouped together, in most 

 of the grains the yellow predominating. The colors 

 usually are not pure. 



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

 tion the grains all color a light violet; with 0.125 per cent 

 solution the color is very light and deepens rather slowly. 

 It is slightly deeper than in L. odoratus var. shahzada. 

 After heating in water until the grains are completely 

 gelatinized, the solution colors deeply and the gelatinized 

 grains fairly deeply on the addition of iodine. After boil- 

 ing for 2 minutes, the solution colors very deeply and the majority of the grain-residues fairly 

 deeply. The capsules become a deep reddish-violet with an excess of iodine. 



Staining Reactions. — With gentian violet the grains when viewed in masses show a very slight 

 tint at once. After remaining in the solution for 30 minutes they are still only lightly stained, 

 but slightly deeper than the grains of L. odoratus var. shahzada. 



With safranin the grains when viewed in masses show a very slight tint of red. After remaining 

 in the solution for 30 minutes they are still only very lightly stained, but sUghtly deeper than the 

 grains of L. odoratus var. shahzada. 



Temperature Reaction. — The temperature of gelatinization is 68° to 70° C, mean 69°. 



Effects of Various Reagents. — With chloral hydrate-iodine a few grains begin to react at once. 

 A few are gelatinized in a minute, about one-third in 5 minutes, one-half in 15 minutes, and two- 

 thirds in an hour. The grains assume a light violet tint at once, which later becomes a pinkish- 

 brown. An interrupted band of dark blue a little distance from the margin is more often connected 

 with the stained gelatinous mass which has formed at one or more points on the border than in 

 L. odoratus var. shahzada. Rounded protuberances appear during the swelling of the grain, and the 

 outline of the gelatinized grain is more or less scalloped. The reaction is qualitatively the same as 

 in L. odoratus var. shahzada. 



With chromic acid the grains begin to react at once. A few are gelatinized in 30 seconds and all 

 in 4J^ minutes. The reaction is qualitatively the same as in L. odoratus var. shahzada. 



The grains begin to react at once with pyrogallic acid. A few are gelatinized in 45 seconds, the ma- 

 jority in 23^ minutes, and all in 4 minutes. The gelatinized grains are convoluted, and one or both 

 ends are divided. The reaction is qualitatively the same as in the grains of L. odoratus var. shahzada. 



Reaction with ferric chloride begins at once. A few grains are gelatinized in 5 minutes, about 

 one-fifth in 15 minutes, and two-fifths in 30 minutes. After remaining in the reagent for an hour, 

 there is little further change. During the reaction the stiiated border is more sharply defined from 

 the central opaque mass than in L. odoratus var. shahzada; otherwise it is qualitatively the same. 



Curve of Reaction-Intensities of Starch of 

 Lathyrua magellanicua var. albus. 



