GENUS BABIANA. 



767 



water until the grains are completely gelatinized, the solution colors lightly and the gelatinized 

 grains very deeply on the addition of iodine. After boiling for 2 minutes the solution colors very 

 deeply and the grain-residues fairly. The capsules all color violet when an excess of iodine is added. 



Staining Reactions. With gentian violet the grains begin to stain very lightly in 1 to 2 minutes 

 and in 30 minutes are colored lightly. Color deeper than that of grains of B. var. {Violacca). 



With safranin the grains begin to stain lightly at once and in 30 minutes are fairly colored, 

 slightly deeper than the grains of B. var. {Violacea). 



Temperature Reaction. The temperature of gelatinization is 81 to 83 C, mean 82. 



Effects of Various Reagents. With chloral hydrate-iodine the reaction begins in 30 seconds and is 

 over in nearly all in 10 minutes. It is the same qualitatively as that of the grains of B. var. {Violacea}. 



Reaction with chromic acid begins in 15 seconds and is over in 2 minutes. It is the same quali- 

 tatively as that of the grains of B. var. (Violacea). 



The reaction with pyrogallic acid begins in 15 seconds, and all are nearly completely gelatinized 

 in 8 minutes. The reaction is the same qualitatively as that of the grains of B. var. (Violacea). 



The reaction with ferric chloride begins in some grains in a minute and is over in 17 minutes. 

 It is the same qualitatively as that of the grains of B. var. (Violacea). 



Reaction with Purdy's solution begins in a few grains in 2 minutes, a few are partially gelati- 

 nized in 12 minutes, and nearly all are partially gelatinized in 30 minutes. The reaction is the 

 same quaUtatively as that of the grains of B. var. (Violacea). 



Differentiation of Certain Starches of the Genus Babiana. 



Iodine Reactions. 

 Intensity and Color. 

 B. var. {yiolacea): Rather light; blue- violet. 

 B. var. {Alhraxiion): Rather light, less than in B. var. 

 {Violacea); blue- violet. 



Staining Reactions. 

 With Gentian Violet. 

 B. var. {Violacea): Light to fair. 

 B. var. (Athraclion): Light, less than in B. var. (7ioiacea). 



With Safranin. 

 B. var. (Violacea): Fair. 



B. var. (Athraclion): Fair, slightly deeper than in B. 

 var. (Violacea). 



Temperature op Gelatinization. 

 B. var. (Violacea): 79 to 81 C, mean 80". 

 B. var. (Athraclion): 81 to 83 C, mean 82. 



Effects of Various Reagents. 



Reaction with Chloral Hydrate-Iodine. 



B. var. (Violacea): Begins in 30 seconds; complete in 



four-fifths in 7}^ minutes, and in all in 20 minutes. 



B. var. (Athraclion): Begins in 30 seconds; complete in 



nearly all in 10 minutes, no further change. 



Reaction with Chromic Acid. 



B. var. (Violacea): Begins in all in 5 seconds; complete 

 in all \nl% minutes. 



B. var. (Athraclion): Begins in aU in 15 seconds; com- 

 plete in all in 2 minutes. 



Reaction with Pyrogallic Acid. 

 B. var. (Violacea): Begins in all in 30 seconds; complete 



in all in 20 minutes. 

 B. var. (Athraclion): Begins in all in 30 seconds; 



nearly complete in all in 8 minutes. 



Reaction with Ferric Chloride. 



B. var. (Violacea): Begins in many in 45 seconds; com- 

 plete in all in 15 minutes. 



B. var. (Athraclion): Begins in some in 60 seconds; 

 complete in all in 17 minutes. 



Reaction with Purdy's Solution. 

 B. var. (Violacea): Begins in many in 15 seconds; com- 



Histoloqicai, Characteristics. 

 Conspicuous Forms. 

 B. var. (Violacea): Simple, isolated except a number of 

 aggregates chiefly in the form of doublets and 

 triplets, isolated grains faceted, surface rounded 

 and smooth, often 2 lines from hilum to facets. 

 Hemispherical with usually 1 to 3 pressure facets 

 at base, and spherical. 

 B. var. (Athraclion): Same as in B. var. (Violacea). 



Hilum Form, Number, and Position. 



B. var. (Violacea): Form indistinct to fairly distinct, 

 comparatively large round spot or sometimes a 

 cavity; rarely fissured; occasionally 2 liila. Posi- 

 tion usually very shghtly eccentric. 



B. var. (Athraclion): Form fairly distinct, otherwise the 

 same as in B. var. (Violacea). Position usually 

 very slightly eccentric. 



Lamelke General Characteristics and Number. 



B. var. (Violacea): Not as a rule distinct, rather coarse, 



regular, continuous, of the shape of the grain near 



the margin. Probably 5 to 6. 

 B. var. (Athraclion): Less distinct than in B. var. 



(Violacea), otherwise the same. Number not 



estimated. 



Size. 



B. var. (Violacea): From 3 to 20/i, commonly 14;i. 

 B. var. (Athraclion): From 2 to 19;i, commonly 12;j. 



PoLARiscopic Properties. 



Figure. 



B. var. (Violacea): Usually shghtly eccentric, distinct, 



clear-cut and regular. 

 B. var. (Athraclion): The same as in B. var. (Violacea). 



Degree of Polarization. 

 B. var. (Violacea): Low to high, usually fair. 

 B. var. (Athraclion): Low to fairly high, less than in 

 B. var. (Violacea). 



Polarization vnlh Selenite Quadrants and Colors. 



B. var. (Violacea): Quadrants usually well defined, reg- 

 ular in shape, and unequal in size. Colors usually 

 pure. 



B. var. (Athraclion): Quadrants the same as in B. var. 

 (Violacea). Colors usually pure. 



plete in two-thirds in 4 minutes. 

 B. var. (Athraclion): Begins in a few in 120 seconds; 

 nearly all partially gelatinized in 30 minutes. 



