672 



STARCHES OF AMARYLLIDACE^. 



Chart No. 233. 



GV S T CI CA PA FC P S Cl PA CA 



Curve of Reactioa-lntensitiea of Starch of 

 Narcissus incomparabilis. 



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

 with 0.125 per cent solution they color fairly and the color deepens slowly. The color is the same 

 as that of the grains of A^. horsfieldii. After heating in water until all the grains are completely 

 gelatinized, the solution colors fairly deeply and the grains deeply on the addition of iodine. After 

 boiling for 2 minutes the solution colors very deeply, but the grain-residues less. With an excess 

 of iodine the capsules color violet, and most of them contain some blue-reacting starch. 



Staining Reactions. With gentian violet the grains begin to stain in 3 minutes and in 30 min- 

 utes they are but lightly stained. The coloration is less 

 than that of the grains of A'^. horsfieldii. 



With safranin the grains begin to stain very lightly in 

 a minute and in 30 minutes they are lightly stained. The 

 reaction is less than that of the grains of N. horsfieldii. 



Temperature Reaction. The temperature of gelatini- 

 zation is 75.5 to 77 C, mean 76.25. 



Effects of Various Reagents. With chloral hydrate- 

 iodine the reaction begins in some grains in a minute and 

 in most of the grains in 3 minutes. About one-fifth are 

 gelatinized in 15 minutes, one-fourth in 30 minutes, one- 

 half in 55 minutes, and two-thirds in IJ^ hours. The 

 reaction is qualitatively the same as that of the grains of 

 A'^. hwsfieldii. 



Reaction with chromic acid begins in 45 seconds and 

 is over in 5J^ minutes. It is qualitatively the same as 

 that of the grains of A'^. horsfieldii. 



The reaction with pyrogallic acid begins in some 

 gi-ains in 30 seconds and is general in 3 minutes. Some 

 are completely gelatinized in 10 minutes, one-third in 15 

 minutes, one-half in 20 minutes, and nearly all in 30 minutes. The reaction is qualitatively the 

 same as that of the grains of A'^. horsfieldii. 



The reaction with ferric chloride begins in some grains in 4 minutes. Most of the grains are 

 completely gelatinized in 30 minutes and all in 45 minutes. The reaction is qualitatively the same 

 as that of the grains of A'^. horsfieldii. 



With Purdy's solution there is a slight reaction in a few grains in IJ^ minutes, and these be- 

 come partially gelatinized in 20 minutes. The reaction is qualitatively the same as that of the 

 grains of A'^. horsfieldii. 



STARCH OF NARCISSUS ODORUS. (Plate 60, figa. 357 and 358. Chart 234.) 



Histological Characteristics. In form the grains are usually simple. There are a few compound 

 grains and aggregates, usually of two components. Grains with pressure facets were rare. The 

 surface of the grains is often irregular, owing to small projections and depressions. The conspicuous 

 forms are ovoid to oval and elliptical. There are spherical, triangular, irregularly pyriform, dome- 

 shaped, hemispherical, and various irregular forms. Broad grains are commonly about half as thick 

 as they are broad, but the narrow grains are about as thick as wide. 



The hilum is usually a small, not very distinct round spot, eccentric about two-fifths to one- 

 third of the longitudinal axis, seldom double or multiple. It is also occasionally elongated or lentic- 

 ular in form. It is rarely fissured, and the fissuration is in the form of a single line, or a small cross, 

 and clear-cut; or very rarely it is irregularly stellate. 



The lamella are not distinct; on many grains they are invisible. When they can be made out 

 they appear as irregular, continuous rings much more distinct near the hilum, and rather fine in 

 iu)mparison with the lamellse of other narcissi. There are about 10 to 12 on the larger grains. 



The grains vary in size from 3 to 38n. The common size is 22;u. 



Poluriscopic Properties. The figure is usually eccentric anil distinct, generally not clear-cut, 

 but in many grains the lines are blurred and indistinct, and often bent or otherwise tlistorted. 



The degree of polarization is fairly high. It varies much in different grains, in ditferent aspects 

 of the same grain, and may be very low or almost absent in large areas of the same aspect of a given 

 grain. It is less vai-jable and slightly less in degree than in the grains of A'^. horsfieldii. 



