GENUS MUSCARI. 



685 



STARCH OF MUSCARI COMPACTUM. (Plate 44, figs. 261 and 262. Chart 169.) 



Histological Characteristics. — In farm, both simple and compound grains, and a few aggregates 

 and clumps are observed. Some of the aggregates consist of one large grain and one very small, 

 round grain; others consist of grains of equal size, and others of three or more grains may be seen. 

 The surface is sometimes irregular, owing in some cases to small protuberances at different points. 

 The conspicuous forms are round, oval, ovoid, and transitions to the clam-shell shape. When viewed 

 on edge they are usually broadly lenticular or flattened elliptical. These grains bear close resem- 

 blance to those of M. botryoides, but both the hila and the lamella are less conspicuous, fissiiration 

 of the hilum is frequent, and there is a larger proportion of medium-sized grains. 



The hilum is a small, round or oval spot, centric in the round forms, and eccentric from 

 two-fifths to one-fourth, usually one-third, of the longitudinal axis in other forms. Double hila 

 frequently occur. The hilum is often fissured, and the fissuration may be noted in the form of 

 a single transverse or longitudinal fissure, or a cross, or a combination of fissures of irregular 

 arrangement. The fissures are often ragged. Fissures may occur on either side of the hilum or 

 between a double hila. An irregular cavity may be found at the hilum. 



The lam^llce are distinct, rather coarse, complete rings near the hilum, but finer and of the same 

 shape as the grain near the margin and distal end. They may be somewhat irregular at the latter 

 point, and are probably incomplete in the clam-shell- 

 shaped forms. One lamella near the hilum and one about 

 the middle of the space between the hilum and the distal 

 margin are often especially distinct. There are about 18 

 lamelliE in the larger forms. 



The size of the grain varies from 4 to 44;u. The 

 common size of the oval forms is 24 by 30/u in length and 

 breadth, and of the large round forms 26 by 26/x in 

 length and breadth. 



Polariscopic Properties. — The figure is centric in the 

 round grains and eccentric in other forms. It is distinct 

 and fairly clear-cut. Its lines are rather thick and become 

 thicker towards the margin, and are usually straight. 



The degree of polarization is high. It varies slightly 

 in different grains and sometimes in the same aspect of 

 one grain. It is lower than in M. botryoides. 



With selenite the quadrants are fairly well defined; 

 they are as a whole regular in form and very often of 

 about equal size. The colors are usually pure. 



Iodine Reactions. — With 0.25 per cent Lugol's solu- 

 tion the grains color a deep blue-violet; with 0.125 per cent solution they color fairly and the 

 color deepens rapidly. The color is not quite so deep as that of the grains of M. botryoides. After 

 heating in water until all the grains are completely gelatinized, the solution and the grains color 

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

 and the grain-residues fairly, lightly, or not at all. The capsules all color a red-violet with an 

 excess of iodine. 



Staining Reactions. — With gentian violet the grains begin to stain at once and in 30 minutes 

 they are deeply stained. The color is slightly deeper than that of the grains of M. botryoides. 



With safranin the grains begin to stain at once and in 30 minutes they are deeply stained. The 

 color is deeper than that of the grains of M. botryoides. 



Temperature Reaction. — The temperature of gelatinization is 69° to 71° C, mean 70°. 



Effects of Various Reagents. — With chloral hydrate-dodine reaction begins in most grains in 30 

 seconds. About half are gelatinized in 5 minutes, almost all in 12 minutes, and all in 30 minutes. 

 The reaction is the same qualitatively as that of the grains of M. botryoides. 



Reaction with chromic add begins in some grains at once and in all in 15 seconds, and is over 

 in 2J^ minutes. It is the same qualitatively as that of the grains of M. botryoides. 



The reaction with pyrogallic acid begins in 30 seconds and is over in 5 minutes. It is the same 

 qualitatively as that of M. botryoides. 



Curve of Reaction- In tens! ties of Starch of Muacari 



com pactum. 



