82 



HISTOLOGIC PROPERTIES AND REACTIONS. 



but nearer N. albicans with iodine; and the lowest of 

 the three, but nearer N. albicans, with temperature. 



Table A 19 shows the reaction-intensities in percent- 

 ages of total starch gelatinized at definite intervals 

 (minutes). 



Velocity-reaction Curves. 



This section treats of the velocity-reaction curves 

 of the starches of Narcissus albicans, N. abscissus, and 

 N. bicolor apricot, showing the quantitative differences 

 in the behavior toward different reagents at definite time- 

 intervals. (Charts D311 to D316.) 



The most conspicuous features of these charts are : 



( 1 ) The close correspondence of the curves in their 

 courses in all of the reactions (with the exception of the 

 very rapid sulphuric-acid reaction, in which there is no 

 differentiation) and the tendency mostly to a moderate 

 or low reactivity. 



(2) The relationships of the parental curves to each 

 other and to the curve of the hybrid (excepting the quick 

 sulphuric-acid reaction) vary in the different reactions 

 and during their progress. 



(3) The curve of N. albicans is distinctly higher 

 than that of the other parent in reactions with the chloral 

 hydrate, pyrogallic acid, chromic acid, and nitric acid, 

 the degree of separation varying as 6tated. 



(4) The hybrid curve is the same or practically the 

 same as that of N. abscissus in the reactions with chloral 

 hydrate and chromic acid, being fairly well separated 

 from the curve of the other parent ; and it is lowest in 

 the reactions with pyrogallic acid and nitric acid, it being 

 in both closer to N. abscissus. 



(5) A tendency to an early period of resistance 

 followed by comparatively high reactivity is indicated 

 only in a minor degree, and almost solely that with 

 chromic 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; with 

 pyrogallic acid, chromic acid, and nitric acid at 15 

 minutes ; and with chloral hydrate at 30 minutes or later. 



Re\ction-intensities of the Hybrids. 



This section deals with the reaction-intensities of the 

 hybrids as regards sameness, intermediateness, excess, 

 and deficit in relation to the parents. (Table A 19 and 

 Charts!) 311 to D 316.) 



The reactivities of the hybrid are the same as those 

 of the seed parent in the reactions witli gentian violet 

 and safranin; the same as those of the pollen parent with 

 polarization and chloral hydrate; the same as those of 

 both parents with sulphuric acid, in which the reactions 

 occur too rapidly for differentiation ; intermediate in 

 those witli iodine and chromic acid, in both being closer to 

 those of the seed parent; highest in none; and the 

 lowest in those with temperature, pyrogallic acid, and 

 nitric acid, in one being closer to the seed parent and in 

 two closer to the pollen parent. 



The following is a summary of the reaction-intensi- 

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

 lent parent, 4; same as both parents, 1; intermediate, 2; 

 highest, ; lowest, 3. 



The seed parent seems to be much more potent in 

 influencing the characters of the starch of the hybrid. 



Composite Curves of the Iveaction-intexsities. 



This section treats of the composite curves of the 

 reaction-intensities, showing the differentiation of the 

 starches of Narcissus albicans, N. abscissus, and A T . M- 

 color apricot. (Chart E 19.) 



The most conspicuous features of this chart are : 



(1) The close correspondence of the curves both as 

 to nearness and course. 



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

 parent the higher reactions with iodine, gentian violet, 

 safranin, chloral hydrate, chromic acid, and pyrogallic 

 acid ; the lower reactions with polarization and tempera- 

 ture; and the same reactions with nitric acid and sul- 

 phuric acid. 



(3) In A T . albicans the very high sulphuric-acid reac- 

 tion ; the high reactions with chromic acid and pyrogallic 

 acid, the moderate reactions with iodine, gentian violet, 

 and safranin ; the low reactions with polarization, tem- 

 perature, and nitric acid ; and the very low reaction with 

 chloral hydrate. 



(4) In N. abscissus the very high sulphuric-acid 

 reaction; the high chromic-acid reaction; the moderate 

 reactions with polarization, iodine, safranin, and pyro- 

 gallic acid; the low reactions with gentian violet, tem- 

 perature, and nitric acid ; and the very low reaction with 

 chloral hydrate. 



(5) In the hybrid the very high reaction with sul- 

 phuric acid; the high reaction with chromic acid; the 

 moderate reactions with iodine, gentian violet, safranin, 

 and pyrogallic acid; the low reactions witli polarization, 

 temperature, and nitric acid; and the very low reaction 

 with chloral hydrate. The following is a summary of the 

 reaction-intensities (10 reactions): 



N. albicans 



N. abscissus 



N. bicolor apricot 



Very 

 high. 



High. 



Mod- 

 erate. 



Low. 



Very 

 low. 



20. Comparisons of the Starches of Narcissus 

 empress, n. albicans, and n. madame de 



GRAAFF. 



In histologic characteristics, polariscopic figures, 

 reactions with selenite, reactions with iodine, and quali- 

 tative reactions with various chemical reagents the 

 starches of the parents and hybrid have properties in 

 common in varying degrees of development together with 

 certain individualities which collectively are in each case 

 distinctive of the starch. The differences are, as a whole, 

 of Tather a minor character. In histologic properties 

 the parental starches differ particularly in the number 

 of aggregates, compound and composite grains, irregu- 

 larity', and conspicuous form?, especially as regards the 

 last. The nearly round and short elliptical grains seen in 

 Narcissus albicans are not present in X. empress. There 

 are minor differences in the hilum and lamella?, and the 

 grains are smaller in N. abscissus. In the polarization 

 figures and reactions with selenite there are minor dif- 

 ferences. In the reactions with iodine no qualitative 

 differences were recorded. In the reactions with chloral 

 hydrate, chromic acid, pyrogallic acid, nitric acid, and 



