GENUS SPARAXI8. 



759 



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

 color. The tint is distinctly deeper than in S. grandijlora alba. 



Temperature Reaction. — The temperature of gelatinization is 72° to 73° C, mean 72.5°. 



Effects of Various Reagents. — With chloral hydrate-iodine the reaction begins immediately. A 

 few grains are gelatinized in 30 seconds and all but a few resistant grains in a minute. The reaction 

 is usually complete in the latter in 3J^ minutes. Rarely a broadly triangular grain with curved 

 base and rounded angles is observed, in which gelatinization does not reach completion in 18 min- 

 utes. The grains generally swell uniformly during the reaction, but in the broadly triangular form 

 a small, rounded protuberance appears at the proximal end. The reaction is qualitatively the same 

 aa in S. grandijlora alba. 



The reaction begins immediately with chromic add. A few grains are dissolved in 15 seconds, 

 nearly all in 30 seconds, and all but rare resistant grains in a minute. The reaction is complete in 

 the latter in 1^ minutes. It is qualitatively the same as in S. grandijlora alba. 



The reaction begins immediately with pyrogallic acid. A few are gelatinized in 15 seconds, 

 and all but a few resistant grains in 25 seconds. The reaction is complete in the latter in 45 seconds. 

 It is qualitatively the same as in S. grandijlora alba. 



With ferric chloride the reaction begins immediately. A few grains are gelatinized in 30 sec- 

 onds, nearly all in a minute, and all but rare resistant grains in 3 minutes. The reaction is usually 

 complete in the latter within 10 minutes, but very rarely a broadly triangular grain resists the reagent 

 for 25 minutes. The reaction is qualitatively the same as in S. grandijlora alba. 



The reaction begins at once with Purdy's solution. A few grains are gelatinized in 15 seconds, 

 nearly all in 45 seconds, and all but rare resistant grains in a minute. The reaction is usually com- 

 plete in the latter in 10 minutes. A much smaller number of grains in which the reaction has only 

 proceeded as far as the first stages is found in this starch than in *Si. grandijlora alba. The reaction 

 is qualitatively the same as in S. grandijlora alba. 



Differentiation of Certain Starches of the Genus Sparaxis. 



Histological Chakacteristicb. 

 Conspiciums Forms. 



S. grandijlora alba: Almost wholly single, few compound 

 grains, some aggregates or clumps, isolated grains 

 usually have sharply defined pressure facets, sur- 

 face sometimes irregular. Dome-shaped with 

 sometimes a pointed base, hemispherical, round 

 and nearly round. 



S. var. (Albertine): Essentially the same as in S. grandi- 

 Jhra alba, but with a large proportion of large 

 ovoid, pyriform, and broadly triangular grains. 



Hilum — Form, Number, and Position. 



S. grandijlora alba: Form clear, round spot, or irregular 

 cavity, 2 or more short fissures. Position centric, 

 or eccentric to about 0.33 or 0.25 of the longitudinal 

 axis. 



S. var. (Albertine): Form essentially the same as in 

 S. grandijlora alba. Position centric, or eccentric 

 to about 0.33 to 0.2 of the longitudinal axis. 



Lamelloe— General Characterislics and Number. 



S. grandijlora alba: Usually indistinct, but occasionally 

 fairly coarse complete rings or having the form 

 of the outhne of the grain. About 7 to 9 on roimd 

 and dome-shaped grains. 



S var. (Albertine): Essentially the same as in S. grandi- 

 jlora alba, but less often demonstrable. The same 

 as in S. grandijlora alba. 



Size. 

 S. grandijlora alba: From 3 to 30m, commonly 12ii. 

 S. var. (Albertine): From 3 to 32^, commonly 13/x. 



PoLARiscopic Properties. 

 Figure. 

 S. grandijlora alba: Centric or eccentric, lines frequently 

 not distinct throughout, often either bent or 

 bisected. Double figures fairly frequent. 

 50 



PoLARiscopic Phopbhties. — Continued. 

 Figure. — Continued. 

 S. var. (Albertine): The same as in S. grandijlora alba, ex- 

 cept that the lines are more often distinct through- 

 out their length, and figure more often eccentric. 



Degree oj Polarization. 

 S. grandijlora alba: Fair to high. Variable in different 



grains and in a given aspect of a grain. 

 S. var. (Albertine): Fair to high. On the whole higher, 

 and less variable in a given aspect of a grain. 



Polarization with Selenile — Quadrants and Colors. 

 S. grandijlora alba: Quadrants usually clearly defined, 

 generally irregular in shape and unequal in size. 

 Colors not pure. 

 S. var. (Albertine): Quadrants the same as in <S. grandi- 

 jlora alba, but on the whole less irregular. Colors 

 not pure. 



Iodine RBAcnoNS. 

 Intensiiy and Color. 

 S. grandijlora alba: Fairly deep; blue-violet. 

 <S. var. (Albertine): Deep, much deeper than in S. 

 grandijlora aJba; blue with reddish tint. 



Staining Reactions. 

 Wiih Gentian Violet. 



S. grandijlora alba: Light. 



S. var. (Albertine): Light to fair, deeper than in <S. 

 grandijlora alba. 



With Sajranin. 



S. grandijlora alba: Light. 



S. var. (Albertine): Light to fairly deep, distinctly 

 deeper than in S. grandijlora alba. 



Temperature of Gelatinization. 

 S. grandijlora alba: 71 to 72° C, mean 71.5". 

 S. var. (Albertine): 72 to 73° C, mean 72.6°. 



