GENUS TRITONIA (MONTBRETIA) . 



735 



Differentiation of Certain Starches of the Genus Tritonia. 



Histological Characteristics. 

 Conspicuous Forms. 



T. crocala: Mostly or solely simple, numerous aggre- 

 gates or compounds in form of doublets and trip- 

 lets, many doublets consist of a large grain having 

 a small grain partially embedded, rounded and 

 regular. Few grains with pressure facets. Spheri- 

 cal and transitional forms between them and 

 ovoid and elliptical. Doublets oval to flattened 

 ovoid and broad ovoid. Spherical when seen on end. 



T. crocalavM. lilacina: Essentially the same as in T. crocala. 



T. crocala var. rosea: Essentially the same as in T. 

 crocala, e-xcepting a relatively large number of 

 doublets and a less number of small grains. 



T. securigera: Essentially the same as in T. crocala, except 

 that the spherical forms are more conspicuous, and 

 fewer aggregates. 



T. pottsii: Simple, many grains with pressure facets; 

 rounded and fairly regular, hemispherical, ovoid, 

 rounded ovoid and spherical. Differ materially 

 in general resemblances from T. crocala, but 

 closely resemble T. crocosmwflora. 



T. crocosmceflora: Essentially the same as T. pollsii. 



Hilum Form, Number, and Posilion. 

 T. crocala: Form indistinct, small, round, rarely slightly 



fissured, sometimes multiple. Position centric or 



slightly eccentric. 

 T. crocala var. lilacina: Form essentially the same as T. 



crocala. Position centric or slightly eccentric. 

 T. crocala var. rosea: Form essentially the same as in 



T. crocala. Position centric or slightly eccentric. 

 T. securigera: Form fairly distinct, large, no fissures, 



sometimes multiple. Position centric or slightly 



eccentric. 

 T. pollsii: Form fairly distinct, small, round, single or 



occasionally double, often fissured, a single short 



fissure or 3 fissm'es or stellate. Position usually 



eccentric about two-fifths to one-third of the 



longitudinal axis. 

 T. crocosmwflora: Form distinct, small, round, single, 



rarely double, often a single shallow and short 



fissure, or stellate. Position usually eccentric 



about two-fifths of the longitudinal axis. 



Lamelloe General Characlerislics and Number. 



T. crocala: Very indistinct, fairly fine, regular, continu- 

 ous rings; about 10 on the larger grains. 



T. crocala var. lilacina: Very indistinct, rather coarse, 

 regular, continuous rings; about 7 on the larger 

 grains. 



T. crocala var. rosea: Very Indistinct, regular, compara- 

 tively coarse, continuous rings; about 8 on the 

 larger grains. 



T. securigera: Rather indistinct, rather coarse, regular, 

 continuous rings; about 4 to 5 on the larger grains. 



T. pollsii: Not as a rule distinct; rather coarse, regular, 

 continuous rings; 10 to 12 on the larger grains. 



T. crocosmce flora: Essentially the same as in T. pollsii; 

 8 to 10 on the larger grains. 



Size. 

 T. crocala: From 3 to 26m, commonly 18m- 

 T. crocala var. lilacina: From 3 to 26m, commonly 18/i. 

 T. crocala var. rosea: From 4 to 27m, commonly 17m. 

 T. securigera: From 2 to 30m, commonly 18m. 

 T. pollsii: From 3 to 32m, commonly 20m. 

 T. crocosmceflora: From 2 to 34m, commonly 20m. 



PoLARiscopic Properties. 



Figure. 



T. crocala: Centric or shghtly eccentric, not as a rule, 



clear-cut, lines straight. 

 T. crocala var. lilacina: Essentially the same as in T. crocala. 



PoLARiscopic Properties. Continued. 

 Figure. Continued. 



T. crocala var. rosea: Essentially the same as in T. 



crocala. 

 T. securigera: Essentially the same as in T. crocala. 

 T. pollsii: Usually eccentric, not clear-cut, lines may be 



bent or otherwise distorted. 

 T. crocosmwflora: Essentially the same as in T. pollsii. 



Degree of Polarizalion. 

 T. crocala: Fair, not much variation. 

 T. crocala var. lilacina: Fair, probably slightly higher 



than in T. crocala. 

 T. crocala var. rosea; Fair, probably slightly higher than 



in T. crocala. 

 T. securigera: Fairly high, variable, distinctly higher 



than in T. crocala. 

 T. pollsii: Fairly Iiigh, variable, distinctly higher than 



in T. crocala. 

 T. crocosnuE flora: The same as in T. pollsii, except more 



variable and shghtly higher. 



Polarizalion unlh Selenile Quadranls and Colors. 

 T. crocala: Quadrants, as a rule, not sharply defined, 



tend to be regular in shape, and equal in size. 



Colors fairly pure. 

 T. crocala var. lilacina: Quadrants essentially the same 



as in T. crocala. Colors fairly pure. 

 T. crocala var. rosea: Quadrants essentially the same as 



in T. crocala. Colors fairly pure. 

 T. securigera: Quadrants essentially the same as in T. 



crocala, but greater tendency to inequality in size. 



Colors fairly pure. 

 T. pollsii: Quadi-ants fairly well defined, tend to be 



irregular in shape and unequal in size. Colors 



fairly pure. 

 T. crocosmceflora: Quadrants the same as in T. pottsii. 



Colors fairly pure. 



Iodine Reactions. 

 Intensity and Color. 

 T. crocala: Fair; blue-violet. 

 T. crocala var. lilacina: Fair, slightly more than in T. 



crocala; blue-violet. 

 T. crocala var. rosea: Fair, slightly more than in T. 



crocala; blue-violet. 

 T. securigera: Fair, but not so much as in 2". crocala; 



blue-violet. 

 T. pollsii: Light, less than in T. crocala; blue-violet. 

 T. crocosmceflora: Fair, more than in T. pollsii, but less 



than in T. crocala; blue-violet. 



Staining Reactions. 

 With Gentian Violet. 

 T. crocala: Very lightly. 

 T. crocala var. lilacina: Very lightly, about the same as 



in T. crocala. 

 T. crocala var. rosea: Very lightly, about the same as in 



T. crocala. 

 T. securigera: Very light, lighter than in T. crocata. 

 T. pollsii: Fair, deeper than in T. crocala. 

 T. crocosmceflora: Light, less than in T. pottsii, but more 



than in T. crocata. 



With Safranin. 

 T. crocala: Fair. 

 T. crocala var. lilacina: Fair, about the same as in T. 



crocala. 

 T. crocala var. rosea: Fair, about the same as in T. 



crocala. 

 T. securigera: Very light, much less than in T. crocala. 

 T. pollsii: Fair, about the same as in T. crocala. 

 T. crocosmceflora: Fair, less than in T. pottsii and T. 



crocala. 



