N K HCI88U8. 



BB 



The reactivity of A", veardale perfection is the Mine 

 or practically the same aa that of BH other pan-nt in 

 the polarization reaction; higher in tin- iodine and tem- 

 perature fractions; and lower in the gcntian-violi-t and 

 aafranin reaction*. The reactivity of the hybrid is the 

 r j.rartn-ally the same aa that of N. weardale per- 

 fection in tin- iodine reaction ; intermediate between 

 those of the parents with gentian violet and aafnuiin; 

 :he three in the temperature reaction; and the 

 hi^'hcxt of the three in the polarization reaction. 



Table A 21 show* the reaction-intensities in percent- 

 ages of total starch gelatinized at definite intervals 

 t minutes) : 



TABLB A 21. 



VELOCITY-REACTION CURVES. 



This section treats of the velocity-reaction curves of 

 the .-larches of Xarcissiu weardale perfection, N. ma- 

 dame de graaff, and A", pyratnut, showing the quantita- 

 iitTerences in the behavior toward different reagents 

 at definite time-intervals. (Charts D 323 to D 328.) 



The most conspicuous features of these charts are: 



( 1 ) The close correspondence of the curves in each 

 of the reactions during their progress (the curves of the 

 sulphuric-acid reaction are identical, owing to the ex- 

 tremely rapid reaction), and the tendency of the reac- 

 tions to be moderate to low. 



i The varying relations of the parental curves to 

 each other and the hybrid in the different reactions and 

 i'ting with sulphuric acid) during the progress of 

 the reaction*. 



(3) The curve of 2V. weardale perfection is lower 

 than the curve of the other parent in the chloral-hydrate 

 reaction; higher in those of chromic acid, pyrogallic 

 acid, and nitric acid ; and the same in that of sulphuric 

 acid. In all except the latter they are sufficiently well 

 separated for positive differentiation. 



it) The curve of the hybrid is the lowest of the 

 three in the reaction with chloral hydrate; and the 

 highest with chromic acid, pyrogallic acid, and nitric 

 acid. The relationship is closer to N. weardale perfec- 

 tion in the chloral-hydrate reaction; and to this parent 

 at first and to the other parent later in the reactions 

 with chromic acid, pyrogallic acid, and nitric acid. On 



the whole, however, the relationship is distinctly clc 

 to JV. weardale perfection. 



(6) A tendency to an early period of resistance fol- 

 lowed by comparatively rapid reactivity is noted in the 

 reactions with chromic acid and pyrogallic acid, with 

 suggested resistance in the chloral hydrate reaction. 



(6) The earliest period at In. h the three curves are 

 best separated for differential pur|x>ses is in the sul- 

 phuric-acid reaction at the very beginning of the reac- 

 tion ; in the reactions with chromic acid, pyrogallic acid, 

 and nitric acid at 15 minutes; and in the chloral-hydrate 

 reaction at 60 minutes, or probably quite as good at 

 15 minutes. 



REACTION-INTENSITIES OF TUB HYBRID. 



This section treats of the reaction-intensities of the 

 hybrid as regards sameness, iiitermedi&teneM, excess, 

 and deficit in relation to the parents. (Table A 21 and 

 Charts D 323 to D 328.) 



The reactivities of the hybrid are the same as those 

 of the seed parent in the iodine reaction; the same aa 

 those of the pollen parent in none; the same as those 

 of both parents in the sulphuric-acid reaction, in which 

 the reactions occur too rapidly for differentiation ; inter- 

 mediate in the reactions with gentian violet and safranin, 

 in both being closer to those of the pollen parent; high- 

 est in the reactions with polarization, chromic acid, pyro- 

 gallic acid, and nitric acid, in one being as close to one 

 as to the other parent, and in three HO-.T to the seed 

 parent; and lowest with temperature and chloral hydrate, 

 in both being closer to the pollen parent. 



The following is a summary of the reaction-intensi- 

 ties (10 reactions) : Same as seed parent, 1 ; same as 

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

 2 ; highest, 4 ; lowest, 2. 



The seed parent exercises a distinctly more marked 

 influence than the other parent in determining the char- 

 acters of the starch of the hybrid. The almost entire 

 absence of sameness to one or the other parent and the 

 tendency, on the other hand, to highest and lowest reac- 

 tivities are conspicuous features of the reactions of the 

 hybrid. 



COMPOSITE CURVES OF REACTION-INTENSITIES. 



This section treats of the composite curves of the 

 reaction-intensities, showing the differentiation of the 

 starches of Narcimnu weardale perfection, N. madame 

 de graaff, and A', pyramiu. (Chart E 21.) 



The most conspicuous features of this chart are: 



(1) The close correspondence of all three curves 

 both as to course and nearness, the only well-marked 

 tendency to departure being in the chromic-acid reaction 

 in which all three curves tend to be well separated. 



(2) In N. weardale perfection in comparison with 

 the other parent the higher reactions with iodine, tem- 

 perature, chromic acid, pyrogallic acid, and nitric acid ; 

 the lower reactions with gentian violet, safrauin, and 

 chloral hydrate; and the same or practically the same 

 reactions with polarization and sulphuric acid. 



(3) In \. wear dale perfection the very high sul- 

 phuric-acid reaction; the high chromic-acid reaction; 

 the moderate reactions with iodine, safranin, and pyro- 

 gallic acid ; the low reactions with polarization, gentian 



