422 



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



0.5 per cent of the entire number of grains and also in 

 the total starch in 5 minutes ; in about 1 per cent of the 

 grains and 2 per cent of the total starch in 15 minutes; 

 slight progress in 30 minutes; in about 2 per cent of 

 the grains and 3 per cent of the total starch in 45 min- 

 utes ; little if any further progress in 60 minutes. ( Chart 

 D80.) 



The reaction with copper nitrate begins in rare grains 

 in half a minute. Complete gelatinization occurs in a 

 few grains, less than 0.5 per cent of the entire number 

 of grains, and 1 per cent of the total starch in 5 minutes ; 

 in about 1 per cent of the grains and 2 per cent of the 

 total starch in 15 minutes; slight progress in 30 min- 

 utes; in about 2 per cent of the grains and 3 per cent 

 of the total starch in 45 minutes; in about the same 

 percentage of the grains and 4 per cent of the total starch 

 in 60 minutes. (Chart D 81.) Gelatinization proceeds 

 through the mesial region along the course of deep fis- 

 sures, the reaction in elongated grains being more rapid 

 at the distal margin. 



The reaction with cupric chloride begins in very rare 

 grains in 1 minute. Complete gelatinization occurs in 

 less than 0.5 per cent of the entire number of grains 

 as well as in the total starch in 5 minutes; still in less 

 than 0.5 per cent of the grains and total starch in 15 

 minutes; in about 0.5 per cent of the grains and 1 per 

 cent of the total starch in 30 minutes; in about 2 per 

 cent of the grains and 3 per cent of the total starch in 

 45 minutes; little if any further progress in 60 minutes. 

 (Chart D 82.) Gelatinization proceeds along the course 

 of deep fissures from the hilum to the distal margin, the 

 latter region being gelatinized previous to the proximal 

 end and sides nearby. 



The reaction with barium chloride begins in very rare 

 grains in 1 minute. Complete gelatinization occurs in 

 less than 0.5 per cent of the entire number of grains as 

 well as in the total starch in 5 minutes ; very slight prog- 

 ress in 15 minutes; still in less than 0.5 per cent of the 

 grains and total starch in 30 minutes ; very slight prog- 

 ress in 45 minutes; still in less than 0.5 per cent of the 

 grains and 1 per cent of the total starch in 60 minutes. 

 (Chart D83.) 



The reaction with mercuric chloride begins in very 

 rare grains in 1 minute. Complete gelatinization occurs 

 in less than 0.5 per cent of the entire number of grains 

 as well as in the total starch in 5 minutes; still in less 

 than 0.5 per cent of the grains and 1 per cent of the total 

 starch in 15 minutes; slight progress in 30 and 45 min- 

 utes; in about 1 per cent of the grains and 2 per cent 

 of the total starch in 60 minutes. (Chart D 84.) 



HlPPEASTRUJI ZEPHYR (POLLEN PARENT). 

 (Plate 3, fig. 14; Charts D 64 to D 84.) 

 Histologic Properties. 

 In form the grains are usually simple and isolated, 

 and there are less numbers of aggregates and of com- 

 pound grains than in II. da-ones. The grains have the 

 same characteristics as those described under that parent, 

 except that the long, narrow, root-like or finger-like 

 grains noted in that starch are not seen in this. The 

 grains are more regular in form than those of II. dceones, 

 and any irregularities which occur are due to the same 

 causes as have been described in those grains. It is to 

 be noted, however, that protuberances from the distal and 



proximal ends and sides are less numerous and not so 

 large as in that starch. The conspicuous forms are 

 nearly round, round, long and slender ovoid, short broad 

 ovoid with pointed ends, and elliptical. There are also 

 triangular, plano-convex, and lenticular forms. The 

 broad forms tend to be somewhat flattened, but the other 

 forms are not. The grains are, as a rule, more rounded 

 in form than those of H. dceones, but are very much like 

 them. 



The hilum is less distinct and less frequently fissured 

 than in II. dceones. The fissures usually have the form 

 of an irregularly branched transverse, oblique, or longitu- 

 dinal line, and occasionally small irregular Y-shaped 

 figures. The hilum is sometimes centric, but usually 

 eccentric from 0.46 to 0.3, usually 0.4 of the longitudinal 

 axis. The eccentricity of the hilum is the same as iu 

 H. do?ones. 



The lamella; are less distinct and less fine than in 

 II. dceones, but are otherwise similar in form and arrange- 

 ment. The number counted on the common-sized and 

 larger grains varies from 8 to 18, usually 14. There are 

 fewer lamellae on these grains than in H. dceones. 



The size of the grains varies from the smaller which 

 are 2 by 2/*, to the larger broad forms which are 38 by 

 36/i, and the larger elongated forms which are 38 by 24/t 

 in length and breadth. The common forms are 26 by 

 26/*, 26 by 20/t and less frequently 24 by 14/*. The 

 grains are about the same common size as those of H. 

 dceones, though the large grains are slightly less, and 

 no grains are noted whose transverse exceeds the longi- 

 tudinal axis in length. 



Polariscopic Properties. 



The ■figure varies from centric to very eccentric, 

 fewer grains of the extremes are present than in H. 

 dceones, but a larger number of the mean, hence the 

 average eccentricity is about the same. The figure is 

 usually distinct and clean-cut, and the lines vary from 

 fine to moderately coarse, with more of the former, as in 

 H. dceones. The lines usually intersect obliquely though 

 sometimes they are arranged as a median line with 

 bisected ends and rarely intersect at right angles, and 

 there are fewer grains with the last two methods of 

 arrangement than in II. dceones. The lines are usually 

 straight with broadening towards the margin, but are 

 sometimes bent and bisected, less frequently than in 

 H. dceones. Double and multiple figures are present, but 

 are not quite so numerous as in H. dceones. 



The degree of polarization is high to very high (value 

 83), variation is frequently present in the same aspect 

 of a given grain ; the range of polarization is the same, 

 but fewer grains with a moderately high degree are pres- 

 ent, hence the polarization is a little higher than in H. 

 dceones. 



With selenite the quadrants are usually well defined 

 and generally unequal in size and regular in shape, a 

 little more clearly defined and a little more frequently 

 regular than in H. dceones. The colors are generally 

 pure, the yellow is less frequently pure than the blue, 

 but the colors are usually purer than in H. dceones. 



Iodine Reactions. 

 With 0.25 per cent of Lugol's solution the grains 

 immediately color a moderate bluish violet (value 50), 

 Less blue in tint and deeper in color than in II. dceones; 



