CHAPTER V. 



SUMMARIES OF THE HISTOLOGIC CHARACTERS, ETC. 



This chapter is devoted to the summaries of the histo- 

 logic characters and qualitative and quantitative reac- 

 tions of the starches of hybrid-stocks in relation to the 

 starches of the parent-stocks, and of the microscopic and 

 macroscopic characters of the hybrid-stocks in relation to 

 the parent-stock plants. 



1. THE STARCHES. 



HISTOLOGIC CHARACTERS AND CERTAIN QUALITA- 

 TIVE AND QUANTITATIVE REACTIONS. 



(Tables C, 1 to 17; D; E, 1 to 22; F, 1 to 50; G; H, 1 to 26; and 

 I, 1 to 8.) 



The methods used in this research in the differentia- 

 tion of starches are both quantitative and qualitative. 

 From a glance at the large number of charts and tables 

 that set forth quantitative results the impression may be 

 gained that much more importance is to be attached 

 to the former than to the latter method of investigation ; 

 but this will be found to be unwarranted by the consider- 

 able space that has been given to and the remarkably 

 valuable results that have been recorded under qualita- 

 tive reactions. In fact, the qualitative method has been 

 found to have far the larger and more varied, and an at 

 least equally important, field of usefulness. Unfortu- 

 nately very little data included under histologic and 

 qualitative records lend themselves to chart-making, or to 

 such forms of tabulation, as have proven so valuable in 

 the preceding chapter and elsewhere in this memoir. 

 Hence, the records herein summarized are presented in 

 a modified arrangement that is particularly well adapted 

 to set forth only a certain but an important aspect of 

 the comparative peculiarities of hybrid and parental 

 properties. 



From the records found in various parts of this work 

 it will be noted that the starch of the hybrid exhibits, his- 

 tologically, physically, and physico-chemically, not only 

 both unipareutal and biparental inheritance, but also 

 individualities that are not observed in either parent; 

 and that any given parental character that appears in the 

 hybrid may be found in quality and quantity to be the 

 same or practically the same as that of one parent or both 

 parents, or of some degree of intermediateness, or de- 

 veloped in excess or deficit of parental extremes. More- 

 over, each unit character and unit character-phase (see 

 Preface and Chapter I, Section 8) is to such a degree 

 independent of the others that one unit-character or 

 character unit-phase may be identical with or very close 

 to that of one parent, while another bears the same rela- 

 tion to the other parent, etc. Thus, in regard to the unit- 

 characters (especially the lamellae), the hybrid may show 

 a very close relationship in the distinctness of the lamella? 

 to one parent, but in the forms of the lamellae to the other 

 parent ; in fineness or coarseness it may be exactly inter- 

 mediate; while in variety, or distribution, or number 

 it may be found at the same time to have the most vary- 

 ing relationships. In a word, in the summing up of the 

 parental relationships it is usually recorded in each of 

 the designations of study (hihun, lamella?, size, polari- 

 284 



scopic reactions, iodine reactions, and gelatinization 

 reactions with each of the different reagents) that a num- 

 ber of correlated unit-characters or unit-character-phases 

 are separable, and that there is a most remarkable and 

 inexplicable swinging to one or the other parent of 

 unit character-development and unit character-phase- 

 development. 



These records show collectively an extraordinary 

 variability in the character relationships of the hybrid 

 to the parents; an independence of each unit-character 

 and unit-character-phase of every other in the direction 

 and degree of its development; an absolute unpredicta- 

 bility at the present embryonic stage of our knowledge 

 of the form, in which, if at all, any given unit-character 

 or unit-character-phase of either or both parents may 

 appear in the hybrid ; and the closer relationship usually 

 of the hybrid in the sum-total of the group-characters 

 or character-phases included in every designation, and 

 of these designations collectively, to one or the other 

 parent. For instance, among the data pertaining to the 

 histologic properties of Brunsdonna sand era? alba, under 

 the designation form it will be noted that the starch 

 grains are more like those of Amaryllis belladonna than 

 those of Brunsvigia Josephines in that they are usually 

 simple and isolated, in their regularity of outline, and in 

 their conspicuous forms; yet in other respects they are 

 more like those of Brunsvigia josepliina because of the 

 presence of a relatively large number of compound 

 grains, of a few small aggregates that consist of 2 or 3 

 components, and of a peculiar form of compound grain, 

 both of which latter are found in this parent but not in 

 Amaryllis belladonna. In the data relating to the la- 

 mella?, the hybrid is closer in form and arrangement to the 

 corresponding parts of the grains of Amaryllis bella- 

 donna; but in average number it is closer to the other 

 parent. In the chloral-hydrate reactions the hybrid in its 

 quantitative reactions shows a decidedly greater sensitiv- 

 ity than either parent, but it is distinctly closer io Amaryl- 

 lis belladonna than to Brunsvigia Josephines. In other 

 reactions the starch is the same or practically the same as 

 one parent or the other or both parents, or of some degree 

 of intermediateness, or of less or even very decidedly less 

 sensitivity than in either parent, very commonly of the 

 latter category. In the qualitative reactions it is in cer- 

 tain well-defined respects closer to Amaryllis belladonna 

 than to the other parent, and in others the reverse; but 

 on the whole the inclination is distinctly toward Amari/1- 

 lis belladonna. 



Moreover, forms of gelatinization are seen in the hy- 

 brids that are individual. In this hybrid it will be found 

 that in the aggregate the gelatinization phenomena re- 

 corded under each reagent incline more or less markedly 

 toward Amaryllis belladonna. With other hybrids the 

 greatest variability of parental relationships may be 

 noted, as, for instance, in Hippeastrum, where it will 

 be found that with one reagent the relationship may be 

 closer to one parent and with another to the other, and 

 more or less marked differences mav be noted in the 



