620 



STABCHES OF CONVALLARIACEJB. 



Polariscopic Properties. — The figure is usually eccentric, fairly distinct, and usually well defined. 

 Ita lines tend to be thick, often thicker as they near the margin; they are never bent. 



The degree of polarization is fair. It varies in different grains, the large grains being more 

 polariscopic than the small grains; but it does not vary much in different aspects of the same grain. 

 It is slightly lower than that of the grains of T. grandiflorum. 



With selenite the quadrants are well defined, usually fairly regular in shape, but unequal in 

 size. The colors are not pure. 



Iodine Reactions. — With 0.25 per cent Lugol's solution the grains color a deep blue-violet; 

 with 0.125 per cent solution they color fairly deeply and the color deepens rapidly. The color is 

 slightly deeper than that of the grains of T. grandiflorum. 

 After heating in water until the grains are completely gel- 

 atinized, the solution colors fairly deeply and the grains 

 deeply on the addition of iodine. After boiling for 2 min- 

 utes the solution colors very deeply and the grain-residues 

 not at all or but slightly. The capsules color a light violet 

 with an excess of iodine. 



Staining Reactions. — With gentian violet and with saf- 

 ranin the grains begin to stain very lightly in a minute, 

 and in 30 minutes they are still very lightly colored. The 

 color is less than that of the grains of T. grandiflorum. 



Temperature Reaction. — The temperature of gelatin- 

 ization is 56° to 57.5° C, mean 56.75°. 



Effects of Various Reagents. — With chloral hydrate- 

 iodine reaction begins at once and is over in 45 seconds. 

 It is the same qualitatively as that of the grains of T. 

 grandiflorum. 



Reaction with chromic add begins at once and is 

 over in 11 seconds. It is so rapid that the individual 

 steps can not be distinguished. 



The reaction with pyrogallic add begins at once and is over in a minute. It is qualitatively 

 the same as that of the grains of T. grandiflorum. 



Reaction with ferric chloride begins at once and is over in 3 minutes. It is the same qualita- 

 tively as that of the grains of T. grandiflorum. 



Reaction with Purdy's solution begins at once and is over in 15 seconds. It is so rapid that 

 the steps can not be made out. 



STARCH OF TRILLIUM SESSILE VAR. CALIFORNICUM. (Plate SO, fig. 300. Chart 204.) 



Histological Characteristics. — In form the grains are simple and isolated with the exception of a 

 very few small aggregates and clumps that are usually easily broken up. No pressure facets were 

 observed. The surface is generally smooth, but sometimes a little irregular in outline, owing to 

 unequal development, causing small depressions and elevations, as in T. grandiflorum. The con- 

 spicuoiis forms are the oval to ovoid, and round. There are also elliptical, pyriform, reniform, 

 lenticular, and various irregular forms. Some grains are about two-thirds as thick as they are 

 broad, and most are less thick than broad. 



The hilum is not usually distinct. It is a large round or lenticular spot, generally eccentric 

 about two-fifths or less of the longitudinal axis of the grain, and in or near the median line. It is 

 rarely fissured, the fissure being single, clean-cut, broad, and short or long. 



The lameUce are invisible. 



The grains vary in size from 2 to 14/i. The common size is 8/«. 



Polariscopic Properties. — The flgure is usually eccentric, fairly distinct, and generally clear-cut. 

 The lines are rather thick, and in some grains become thicker but not well defined as they near the 

 margin. They are rarely bent. 



The degree of polarization is fair. It varies in different grains, the larger grains being more 

 polariscopic than the small, but not varying much in different aspects of the same grain. It is 

 lower than that of the grains of T. grandiflorum. 



Curve of Reaction-Intensities of Starch of Trillium 

 ovatum. 



