410 STARCHES OF LEGUMINOS^. 



With seleniie the quadrants in the unfissured grains arc fairly well defined, irregular in 

 form, and unequal in size. The fissured grains have many areas of each color grouped together, 

 and in some grains the blue predominates, but in most there is more yellow. The colors are 

 usually pure. 



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

 with 0.125 per cent solution they color a light violet, and the color deepens rather slowly. The 

 color is deeper than that in Eugenie peas. After heating in water until all the grains are com- 

 pletely gelatinized, the solution colors a deep blue-green and the grains a very dark blue on the 

 addition of iodine. After boiling for 2 minutes, the solution colors a deep indigo-blue and most 

 of the grain-residues a bright blue. The capsules stain a reddish-violet when an excess of iodine 

 is added. 



Staining Reactions. — With gentian violet and with safranin the grains when viewed in masses 

 show a light tint of violet at once; after remaining in the solution for 30 minutes they are lightly 

 stained. The color of the grains is slightly deeper than in Eugenie peas. 



Temperature Reaction. — The temperature of gelatinization is 68° to 69° C, mean 68.5°. 



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

 About one-eighth are gelatinized in 5 minutes, one-third in 15 minutes, and two-thirds in 30 minutes. 

 After remaining in the solution for an hour no more appear to be gelatinized, but they are changed to 

 a golden-brown color by the reagent. The grains on adding the reagent at once assume a light violet 

 tint, which soon becomes of a light rose color. The refractive and non-refractive lamella? are sharply 

 differentiated, and striae are clearly observed on the refractive lamellae. Gelatinization begins 

 either at one end or at the clear line of division in the reniform grains, as a mass of deeply stained 

 starch, sometimes irregular in shape. From this mass strands of color often pass, but eventually 

 the mass of color advances over the entire grain. The gelatinized grain is usually regular in outline, 

 but occasionally broken and ragged at some points. The reaction resembles those observed in the 

 starches of Vida, Phaseolus, and Lathyrus. 



Reaction begins at once with chromic acid. A few grains are dissolved in 2 minutes, the majority 

 in 5 minutes, while an occasional resistant grain may take 12 minutes before it passes completely 

 into solution. The reaction is qualitatively the same as in the bean starches generally. 



The reaction with pyrogallic acid begins at once. A few grains are gelatinized in 40 seconds, 

 the majority in iK minutes, and all in 2 minutes. The reaction is qualitatively the same as noted 

 in the bean starches generally. 



With ferric chloride the grains begin to react in 30 seconds by the hilum and lamellae becoming 

 distinct. A few are gelatinized in 15 minutes, and about one-fourth are gelatinized in an hour. 

 The reaction is qualitatively the same as noted in the bean starches generally. 



Reaction with Purdy's solution begins in 30 seconds. A few grains are gelatinized in 8 minutes 

 and about nine-tenths in 30 minutes. Rows of brilliant granules, which seem to be remains of 

 lamellae, appear during solution of the grain. The phenomena of this reaction are similar to those 

 observed with pyrogallic acid, but the remains of the lamellae are generally less convoluted and the 

 outline of the gelatinized grain is more regular. The reaction is qualitatively similar to those 

 observed in bean starches generally. 



Differentiation of Certain Starches of the Genus Pisum. 



HlSTOLOQICAIi ChARACTEBISTICS. 



Conspicuous Forms. 



Eugenie (green): Simple and iaolated, much fissured. 

 Round, ovoid, and oval rosettes, linear aggre- 

 gates; part-grains triangular, and quadrangular, 



Histological Chak actebiswcs. — C!ontinued . 



Hilum — Form, Number, and Position. 



Eugenie (green): Not demonstrable. Position probably 



centric or slightly eccentric. 

 Eugenie (yellow): Same as in Eugenie (green). Position 



crescentic, hemispherical. Few grains of bean i probably centric or slightly eccentric. 



type. 



Eugenie (yellow): Same as in Eugenic (green). 



Thomas Laxlon: Same as in Eugenie (green). 



Electric Exlra Early: Simple and isolated, often fissured. 

 Ovoid, oval, elliptical, reniform. 



Mammoth Grey Seeded: Essentially the same as in Elec- 

 tric Extra Early. 



Large While Marrowfat: Essentially the same as in Elec- 

 tric Extra Early. 



Thomas Laxlon: Same as in Eugenie (green). Position 

 probably centric or slightly eccentric. 



Electric Exlra Early: Hilum probably a granular non- 

 lamellated space, usually fissured. Position cen- 

 tric or slightly eccentric. 



Mammoth Grey Seeded: Same as in Electric Extra Early. 

 Position centric or slightly eccentric. 



Large While Marrowfat: Same as in Electric Extra Early. 

 Position centric or slightly eccentric. 



