564 



DATA OP PROPERTIES OF STARCHES OF PARENT- AND HYBRID-STOCKS. 



small granules which begin to gelatinize almost at once. 

 The secondary starch becomes homogeneous-looking and 

 very refractive, and as the primary starch and the less 

 resistant portions of the secondary starch are gelatinized, 

 the grain swells and the more resistant part of the sec- 

 ondary starch forms a refractive homogeneous-looking 

 band at the margin, which gradually grows thinner and 

 more nearly transparent until it is all gelatinized and 

 only the capsule remains. The gelatinized grains are 

 much swollen, have rather thick capsules, and are much 

 distorted. 



Comparison of the sulphuric-acid reactions between 

 N. abscissus and N. albicans shows : 



The hilum and lamellae are as distinct as in N. albi- 

 cans. Gelatinization progresses according to two 

 methods instead of but one. The first, which is seen 

 in a great majority of the grains, is very nearly the 

 same as that described for all the grains of N. albicans; 

 the differences are that the primary starch is usually 

 divided into but four or five portions which gelatinize 

 more or less independently of the secondary starch. In 

 some grains it is not divided at all and gelatinizes as a 

 separate part more slowly than does the secondary 

 starch. The secondary starch is finely striated at first, 

 but the more resistant portion forms a homogeneous- 

 looking refractive band as in N. albicans. In the second 

 method, which is not seen" in N. albicans, 2 furrows or 

 fissures extend transversely from either side of the 

 hilum to the margin and the material distal to them 

 and to the hilum is divided by concentric fissures into 

 portions of varying size, which are gelatinized from the 

 margin in to the hilum. The starch at the proximal 

 end and sides nearby is pushed to the margin and then 

 forms a homogeneous-looking, thick, refractive band 

 which is gelatinized rather slowly, after the rest of the 

 grain is gelatinized. The gelatinized grains are as much 

 swollen, have as thick capsules, and are even more dis- 

 torted than in N. albicans. 



NARCISSUS BICOLOR APRICOT (HYBRID). 



(Plate 12, fig. 72 ; Charts D 311 to D 316.) 

 HISTOLOQIC PROPERTIES. 



In form the grains are usually simple and isolated 

 and there are fewer compound grains and aggregates than 

 in either parent, and in this respect the hybrid is closer 

 to N. albicans. Both compound grains and aggregates be- 

 long to the same types as were described under N. albi- 

 cans. There are as many simple grains in which a clear 

 distinction can be made between a primary and a sec- 

 ondary starch formation as in N. abscissus. The grains 

 are not so often irregular in form as in N. albicans and 

 much less than in N. abscissus, and the irregularities, 

 if present, are due to the same causes as in N. albicans. 

 The conspicuous forms are ovoid, triangular, plano- 

 convex, and nearly round. The additional forms are 

 irregularly quadrilateral, lenticular, and elliptical. 



In form N. bicolor apricot shows a somewhat closer 

 relationship to N. albicans than to N. abscissus. 



The hilum when not fissured is not very distinct as 

 in N. albicans. It is fissured as often as in N. abscissus, 

 and not so deeply or so extensively as in either parent. 

 The fissures have the following forms: (1) A single 

 straight, longitudinal or transverse line; (2) cruciate; 

 (3) an irregularly stellate mass of fissures. The fissures 



are not so varied in form as in either parent. The hilum 

 is sometimes centric, but in the majority of the grains 

 it is eccentric from 0.45 to 0.27, usually 0.34, of the 

 longitudinal axis. 



In the character of the hilum N. bicolor apricot shows 

 a somewhat closer relationship to N. abscissus than to 

 N. albicans. The degree of eccentricity is the same in 

 both parents and hybrid. 



The lamellce are, as in N. albicans, not very distinct, 

 rather fine continuous rings, with the same arrangement 

 as in N. albicans. The number on the grains can not 

 be determined. 



In the character of the lamella N. bicolor apricot 

 shows a closer relationship to N. albicans than to N. 

 abscissus. There is, however, no marked difference in 

 the character of the lamellae between the two parents 

 and the hybrid. 



The grains vary in size from the smaller which are 

 4 by 4/i, to the larger which are 30 by 40/u, in length 

 and breadth. The common sizes are 20 by 20/t, 20 by 

 18/t, and 18 by 22/j.. In size N. bicolor apricot is some- 

 what closer to N. albicans than to N. abscissus. The 

 three starches are, however, very close to one another 

 in size. 



POLABISCOPIC PROPERTIES. 



The figure as in N. albicans is moderately distinct 

 and usually well defined. The lines cross at right angles 

 or at acute angles which do not vary greatly in size. They 

 are more often bent and bisected than in N. albicans. 

 There are a very few figures which have the form of a 

 conjugate hyperbola or of a long line bisected at both 

 ends. 



The degree of polarization varies from low to high 

 (value 37), the same as in N. albicans and less than in 

 N. abscissus. There is the same amount of variation 

 in a given aspect of the same grain as in N. albicans. 



With selenite the quadrants are, as in N. albicans, 

 moderately well defined and unequal in size, but are 

 somewhat more irregular in shape than in N. albicans. 

 The colors are usually not pure, as in N. albicans, and 

 there are very few grains which have a greenish tinge. 



In the degree of polarization, the character of the 

 figure, and the appearances with selenite, N. bicolor apri- 

 cot shows a much closer relationship to N. albicans than 

 to TV. abscissus. 



IODINE REACTIONS. 



With 0.25 per cent Lugol's solution, the grains all 

 color a moderate violet tinged with blue (value 55), 

 the same as in N. albicans, and much more than in N. 

 abscissus. With 0.125 per cent Lugol's solution the grains 

 all color a light violet, the same as in N. albicans and 

 more than in N. abscissus. After heating in water until 

 the grains are all gelatinized and then treating with a 

 2 per cent Lugol's solution, the gelatinized grains all 

 color a moderate to deep indigo, and the solution a moder- 

 ate indigo, as in N. abscissus. If the preparation is 

 boiled for 2 minutes and then treated with an excess 

 of 2 per cent Lugol's solution, the grain-residues all 

 color a light or a light to moderate indigo as in N. ab- 

 scissus, the capsules a red or a reddish violet, and the 

 solution a very deep indigo as in both parents. 



Qualitatively and quantitatively the reactions with 

 iodine of the unheated grains show a closer relationship 



