GENUS ORNITHOGALUM. 



557 



Curve of Reaction-Intensities of Starch of Ornithogalum 

 umbellatum. 



The degree of polarization is fairly high. It is proportionately much higher in the larger grains, 

 but does not vary much in different aspects of the same grain. It is not so high as that of the grains 

 of 0. nutans. 



With selenite the quadrants are usually not very well defined, are fairly regular in shape, and 

 unequal in size. The colors are pure. 



Iodine Reactions. ^\Yith 0.25 per cent Lugol's solution the grains color a fairly deep blue-violet; 

 with 0.125 per cent solution they color rather lightly and the color deepens fairly rapidly. The 

 color is less than that of the grains of O. nutans. After heating in water until all the grains are com- 

 pletelj^ gelatinized, the solution colors fairly and the grains deeply on the acUlition of iodine. After 

 boiling for 2 minutes the .solution colors tleeply and the 

 grain-residues rather lightly. On the addition of an excess 

 of iodine all the capsules may be seen to be colored a red- 

 dish-\nolet. IMost of them retain more or less blue-react- 

 ing starch. 



Staining Reactions. With gentian violet the grains 

 begin to stain at once and in 30 minutes are fairly deeply 

 stained, not so deeply as those of 0. nutans. 



With safranin the grains begin to stain at once and 

 in 30 minutes are deeply stained, not so deeply as those 

 of 0. nutans. 



Temperature Reaction. The temperature of gelatin- 

 ization is 56.5 to 57 C, mean 56.75. 



Effects of Various Reagents. With chloral hydrate- 

 iodine the reaction begins in 30 seconds. It is over in 

 nearly all in 3 minutes and in all in 7 minutes. It is quali- 

 tatively the same as that of the grains of 0. nutaiis. 



Reaction with chromic acid begins in a very few 

 seconds and is over in 30 seconds. The reaction is qual- 

 itatively the same as that of the grains of 0. nutans. 



The reaction with pyrogallic acid begins in 15 seconds. It is over in most grains in 2 minutes 

 and in all in 4 minutes. The reaction is the same qualitatively as that of the grains of 0. nutans. 



With feme chloride the reaction begins in a few grains in 15 seconds, and is over in 12 minutes. 

 The reaction is qualitatively the same as that of the grains of 0. nutans. 



Reaction ^vith Pwdy's solution begins in a very few seconds and is over in IJ^ minutes. It is 

 qualitatively the same as that of the grains of 0. nutans. 



STARCH OF ORNITHOGALUM NARBONENSE (PYRAMIDALE). 



(Plate 38, figs. 225 and 226. Chart 151.) 



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

 a few doublets. No pressure facets were noted. The surface is quite irregular and somewhat varied, 

 owing to irregular additions in the form of lamellated or amorphous accretions, chiefly to the distal 

 end or to one or both sides near the distal end. These additions, and sometimes also the distal 

 end of the original grain, are irregular, with many small depressions and slight elevations of the 

 surface. The conspicuous form is the ovoid, with a pointed, squared, or irregular distal end; there 

 are also many quadrangular grains with rounded proximal ends and irregularly squared distal 

 ends; and fewer spherical, elliptical with ends of equal size or with a bulging proximal end, and 

 triangular forms with rounded angles. There are many irregular forms. The grains are not flat- 

 tened and are of the same thickness as breadth. 



The hilum is a fairly distinct, small, round, or rarely lenticular spot. It is usually eccentric, 

 about one-fourth, less often one-third, of the longitudinal axis, and in or to one side of the median 

 line. There may be 2, or rarely more, hila in a single grain. The hilum is sometimes Cssured. There 

 is usually but one fissure, which is a short, narrow, clear-cut, transverse line, straight or with two 

 curves; sometimes two fissures form a cro.ss, or an irregularly stellate arrangement of a number 

 of fissures. 



The lamellw are distinct, regular, coarse, continuous rings near the hilum, and probably dis- 

 continuous rings near the distal end. They are somewhat coarser but more distinct near the distal 



