N >. HCI88U8. 



S7 



mud intermediate with temperature, but closer to A'. 

 madame de groaff. 



Table A 22 shows the reaction-intensities -f tin- 

 *tarche expressed by tlic percentage of total starch 

 gelatinized at definite time- interval*. 



VKUK-ITY-BKAI-I i .KM. 



Thin section treaU of the velocity-reaction curves 

 <>f tin- -t.m lies of A'orcisnu monarch. N. madam e de 

 graaff, ajul .V. lord robtrtt, showing the quantitative 

 differences in the behavior toward dinVrent reagents at 

 definite tune-intervals. (Chart* 1 .T to 1) 334.) 



most conspicuous features of these charts are : 



( 1 ) The correspondence in the courses of the three 

 curves in all of the reactions (excepting the sulphuric- 

 a. hi reaction in which gelatinization is too rapid for 

 tliir.r.-nuation), and the tendency to moderate to low 

 reactivity. Inclination to separation of the curves if 

 comparatively well marked in the pyrogallic acid. 



I V ) The varying relations of the parental carves to 

 each other and to the curve of the hybrid in all of the 

 reactions (excepting in that with sulphuric acid) during 

 their progress. 



i The curve of A", monarch is distinctly lower than 

 that of the other parent in the reactions with chloral 

 hydrate and pyrogallic acid; distinctly higher with 

 lir.anic acid and nitric acid; and the same with iodine 

 and sulphuric acid. 



(4) The curve of the hybrid is intermediate in the 

 reactions with chloral hydrate, pyrogallic acid, and nitric 

 acid, but close to A', monarch with chloral hydrate and 

 nitric acid, and to the other parent with pyrogallic acid ; 

 and the lowest of the three and well separated from the 

 parental carves in the chromic-acid reaction. 



(5) A tendency to an early period of resistance 

 fallowed by comparatively high reactivity is evident, 

 especially in the three starches in the pyrogallic-acid 

 reaction and in two starches in the chromic-acid reac- 

 tion, with a suggestion of resistance in the reactions with 

 chloral hydrate and nitric acid. 



(6) The earliest period at which the three curves are 

 best separated for differential purposes is in the reaction 

 with sulphuric acid at the very beginning; in those with 

 chromic acid, pyrogallic acid, and nitric acid probably at 

 15 minutes; and with chloral hydrate at 60 minutes. 



RBACTION-INTBN8ITIB8 OF THE HTBBIO. 



This section treats of the reaction-intensities of the 

 hybrid as regards sameness, intermediateneas, excess, and 

 deficit in relation to the parents. (Table A 22 and 

 Charts D 329 to D 334.) 



The reactivities of the hybrid are the same as those 

 of the aeed parent in the reactions with gentian violet, 

 safranin, and sulphuric acid; the same as those of the 

 pollen parent in the polarization reaction ; the same as 

 those of both parents in the iodine reaction ; intermediate 

 in the reactions with temperature, chloral hydrate, pyro- 

 gallic acid, and nitric acid, being closer to the seed parent 

 in two and to the pollen parent in two ; highest in none ; 

 and lowest in the chromic-acid reaction. 



The following is a summary of the reaction-intensi- 

 ties (10 reactions): Same as seed parent, 3; same as 

 pollen parent, 1 ; same as both parents, 1 ; intermediate, 

 4; highest, 0; lowest, 1. 



The parents appear to share about equally the deter- 

 mination of the properties of the starch of 'the hyl.n.l 

 Ih. re is obviously a tendency to intennediateneM. tin- 

 being recorded in nearly half of the reactions. 



COMPOSITE CURVES OF REACTION-INTENSITES. 



This section treats of the composite curves of the 

 reaction-intensities, showing the differentiation of the 

 starches of \areunu monarch, N. madame de graaff, 

 and N. lord robertt. ( Chart E 22. ) 



The most conspicuous features of this chart are : 



(1) The very close correspondence in all three curves 

 in nearness and during their course, excepting in the 

 chromic-acid reaction, in which the curve of A', monarch 

 is well separated from the curves of the other parent and 

 the hybrid. 



(2) In N. monarch in comparison with the other 

 parent the higher reaction with polarization, gentian vio- 

 let, temperature, chromic acid, pyrogallic acid, and nitric 

 acid ; the lower with chloral hydrate ; and the same with 

 iodine and sulphuric acid. 



(3) In A 7 , monarch the very high sulphuric-acid 

 reaction ; the high chromic-acid reaction ; the moderate 

 reactions with polarization, iodine, gentian violet, 

 safranin, and temperature; the low reactions with pyro- 

 gallic and nitric acids; and the very low reaction with 

 chloral hydrate. 



(4 ) In A', madame de graaff the very high sulphuric- 

 acid reaction ; the absence of a high reaction ; the mod- 

 erate reactions with iodine, gentian violet, safranin, and 

 chromic acid ; the low reactions with polarization, tem- 

 perature, pyrogallic acid, and nitric acid; and the very 

 low reaction with chloral hydrate. 



The following is a summary of the reaction-intensi- 

 ties (10 reactions) : 



23. COMPARISONS OF TUB STARCHES or NABCIMCS 



LJEEIMUI MINNIE II I' ME, N. TRIAKDRCS AI.Bt H. AND 

 N. AGNES HARVBT. 



In histologic characteristics, polariscopic figures, 

 reactions with selenite, reactions with iodine, and quali- 

 tative reaction with the various chemical reagents the 

 starches of the parents and hybrid exhibit properties in 

 common in varying degrees of development, which col- 

 lectively are in each case distinctive. The differences 

 are, on the whole, of a minor character, indicating dose 

 relationships of the three starches. In histologic prop- 

 erties in ffarcutuM triandnu albiu in comparison with 

 the other parent there are found a larger proportion of 

 compound grains but fewer aggregate*, somewhat fewer 

 grains with primary and secondary deposits, and the 

 grains are less irregular; the hilum is more often more 

 deeply and more extensively fissured; the lamelbe an 

 leas often distinct and not so fine ; and the grains are, 

 as a whole, smaller than in A", letdtii ninnit hume. 



