438 



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



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

 60 minutes. (Chart D 103.) 



Gelatinization may proceed along well-defined fis- 

 sures through the mesial region, but more often before 

 much progress is made in the mesial region it may ad- 

 vance rapidly at the distal end of elongated grains or 

 around the entire margin of ovoid grains, the process 

 being accompanied with extension and considerable flut- 

 ing of the capsule. This fluting is more marked than in 

 H. katherince. 



The reaction with barium chloride begins in rare 

 grains in half a minute. Complete gelatinization occurs 

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

 and total starch in 5 minutes; in about the same per- 

 centage of each in 35 minutes ; in about the same percent- 

 age in 30 and 45 minutes ; and in less than 0.5 per cent 

 of the grains and about 1 per cent of the total starch 

 in 60 minutes. (Chart D 104.) 



The reaction with mercuric chloride begins in rare 

 grains in 1 minute. Complete gelatinization occurs in 

 but rare grains and the process begun in but few, less 

 than 0.5 per cent of both the entire grains and total 

 starch in 5 minutes; about 0.5 per cent of the grains 

 and 1 per cent of the total starch in 15 minutes; about 

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

 in 30 minutes; little if any further progress in 45 and 

 60 minutes, respectively. (Chart D 105.) 



ILemanthus andbomeda (Hybeid). 



(Plate 3, fig. 18; Charts D 85 to D 105.) 

 Histologic Properties. 



In form the grains are usually simple and isolated 

 with the exception of a few which occur in aggregates of 

 2, 3, or 4 components. There are some compound grains, 

 but not so many as in H. magnificus. The latter usually 

 are doublets, but may have 3 or 4, or very rarely more, 

 components, and they are similar in appearance and 

 arrangement to those seen under II. magnificus. The 

 grains tend to be more irregular in form than in either 

 parent, and the irregularities are due to the following 

 causes: (1) Protuberances which are usually finger-like, 

 but which may be large and rounded or nipple-like; 

 (2) to a shifting of the longitudinal axis causing a curva- 

 ture at one end; (3) to moderately well-defined pressure 

 facets of varying size and position; (4) to depressions 

 and notches in the margin, one deep semi-circular depres- 

 sion at the distal end being characteristic of this grain as 

 distinguished from those of the parents. The components 

 of the aggregates are usually compactly arranged, but 3 

 or 4 in linear arrangement are observed. The conspic- 

 uous forms are ovoid, elliptical, broad lenticular, plano- 

 convex, and dome-shaped. There are also scalene and 

 isosceles triangular, broad reniform, pyriform, almost 

 round, and irregularly quadrilateral forms. In form the 

 grains of H. andromeda more nearly resemble those of 

 H. leathering but there are some scattered grains which 

 are exactly like those characteristic of H. magnificus. 



The hilum is indistinct and when seen is a small, 

 round or lenticular spot which is very seldom fissured. 

 It may be either centric or eccentric from 0.43 to 0.2 

 usually 0.3, of the longitudinal axis. In the characters of 

 the hilum II. andromeda more closely resembles H. kath- 

 erince than H. magnificus. 



The lamella? are so indistinct that it is impossible to 

 form any satisfactory comparison between the hybrid and 

 parents; when they can be demonstrated, they appear 

 as circular or lenticular in form and throughout the rest 

 of the grain they have the form of the outline of the 

 grain. Those counted on the larger grains vary from 

 10 to 25, usually about 18. 



In size the grains vary from the smaller which are 

 4 by ifx to the larger broadened forms which are 50 by 

 40/x, and the large, narrow forms which are 50 by 30/* in 

 length and breadth. The common size is about 30 by 18/t. 

 In size H. andromeda is closer to H. magnificus than to 

 H. katherincB. 



Polariscopic Properties. 



The figure is centric to quite eccentric, considerably 

 less eccentric than in H. katherince, but distinctly more 

 than in H. magnificus. The lines vary from fine to 

 coarse, more of the latter than in II. katherince, and 

 many more than in H. magnificus. The lines intersect 

 each other or are arranged as a median line with bisected 

 ends as noted in both parents ; the intersection is at right 

 angles in more grains than in H. katherince, but in many 

 less than in H. magnificus. The lines are more fre- 

 quently straight, and not quite so often bent as in H. 

 katherince but more frequently than in H. magnificus. 

 The lines are often bisected, about as in both parents. 

 Compound and multiple figures are not commonly pres- 

 ent, though more frequently than in H. katherince, but 

 not nearly so often as in H. magnificus. 



The degree of polarization is high to very high (value 

 82 ) . There is a great deal of variation among the indi- 

 vidual grains, the polarization ranging from a few mod- 

 erately high to some very high, most of them being high ; 

 the variation in the different grains is about as great but 

 the mean is higher than in H. katherince, and the varia- 

 tion is greater and the mean lower than in H. magnificus. 

 The variation in the same aspect of a given grain is not 

 so frequent as in H. katherince but very much more com- 

 mon than in II. magnificus. 



With selenite the quadrants vary from not very well 

 defined to quite sharply defined. The definition is 

 sharper in more grains than in H. katherince but not as 

 sharp in nearly so many as in H. magnificus. In the 

 majority of grains the quadrants are unequal in size and 

 often irregular in shape, not quite so unequal and irreg- 

 ular as in H. katherince but decidedly more so than in 

 H. magnificus. The colors are generally pure, the blue 

 more frequently than in H. katherince, but not so fre- 

 quently as in H. magnificus; the type of impurity is often 

 due to the presence of grains having an extremely high 

 degree of polarization, imparting a greenish tinge to the 

 colors; this type is not observed in H. katherince, but 

 found in H. magnificus. 



In degree of polarization, in character of the figure, 

 and in appearance with selenite U. andromeda is closer 

 to II. katherince than to H. magnificus. 



Iodine Reactions. 

 With 0.25 Lugol's solution the grains color a mod- 

 erate to light violet (value 47), slightly deeper but of 

 about the same reddish tint as in H. katherince, but a lit- 

 tle lighter and more reddish than in II. magnificus; the 

 color deepens gradually, becoming bluer and to about the 

 same depth and tint as in H. katherince, but a little 



