164 



\CTION-INTENSITIES OF STARCJII 



With i ceptions, the figures for the several 



members of each group ami each genus tei d to be distrib- 

 uted among I al division : genus 

 with remarkable uniformity, in some gem 



lumber falling among the very high, 

 high and high reactions, or the very low, or the very 

 low and low n . ami so on. Such diff i 



themselves, arc usually quite definite in making distinct 

 groups which upon comparison will lie found to agree 

 remarkably with botanical classification. Thus Hi} 

 trum, Nerine, Gladiolus, and Tritonia are characti 



icularly by the relatively large number of reactions 

 i number varying in the diffi renl 

 ra) ami the fairly uniform distribution of the re- 

 maining reactions among the other divisions, chiefly 

 among th.' moderate and low. in Lilium, Phaius, and 

 '•(liiiin the characterization is by the very large 

 number of very high reactions and the fairly uniform 

 ribution of the other reactions among the other 

 divisions, nerally among the Inch and mod- 



erate. I" Imaryllis-Brunsvigia, Crinum, Hmmanthus, 

 Iris, Begonia, and Mum variations from these systems 

 may he obsi rvi d because of certain subgeneric peculiari- 

 that have already been referred to. 

 These data indicate quite clearly that peculiarities in 

 the distribution of these reaction-intensities are inti- 

 mately related to generic ami subgeneric divisions, and 

 i the distributions in the case of members of a 

 sel or of a L r 'ims may lie alike or nearly alike there may !»' 

 differences in the sums and averages that arc more or less 

 definitely distinctive. For instance, the distribution in 

 Brunsdonna sandera alba ami /.'. sanderm is identical, 

 urns and averages differ sufficiently to differ- 

 entiate these hybrids. In Nerine, the distributions dif- 

 fer very little; in some cases the sums and averages are 

 absolutely or practically identical, and in others they 

 differ within small to very narrow limits. Under such 

 conditions positive identification of different members 

 of the group can not satisfactorily he made. Correspond- 

 onditions arc found in relation to intergeneric dif- 

 itiation. Thus, the distributions in Hippeastrwm 

 ami Nerine are closely the same, and were dependence 

 ai tin- feature to distinguish genera it would 

 naturally he concluded that the genera are alike; hut 

 upon a careful examination of the two sets of figures it 

 will he found that in Hippeastrwm there is a manifest 

 'ting of dm reai tion-intensities toward 



the very low reactivity end, and in Nerine in the si 



direction, hut to a slightly less degree, so that in the final 

 summing up the sums am] averages in the former fall 

 than in the latter — in Hippeastrwm, ranging from 

 ! is to 925 ami -.'it to 36, respectively; and in Nerine 

 from 869 to 1 199 and 33 to [o. respectively. In I 



and Tritonia, wry closely relati I c the flis- 



tribul | receding 



the bi meets referred to. On th be hand. 



/.ilium ar. 1 i Hum, while in genera] very cl 



in distribution, sum, and average are ver mar 

 different from all other groups. Phaiusv&h 



i the figures of Liliun 

 Iris in its firsl th. im all 



i in the manner of distribution of the rea tion- 

 ities, \vt the sum.- and avi 



somewhat less than iii Nerine. In other words, different 

 genera maj or may not exhibii distinctive peculiarities in 

 the distribution, sum, and average of the reaction-:' 

 sities. The value of such data seems to lay particularly 

 in showing that members of a at are not so 



differentiated as to fall into subgi ons tend to 



e.xhihit a method of distribul ii reaction-intensities 



according to a definite system, which system is composed 

 of the averages of the number of very high, high, moder- 

 ate, low. and very low react ion-inteiis it n ■-. of the a ■■ ■ 

 of the sum of the read ton-intensities, and of the average 

 of the latter. For comparative purposes the sj stem i 

 Miitcd by Hippeastrum, Iris (first three sets), and Lilium 

 may he taken because they -how different types: 



If the figures for any given member of any one of the 

 genera represented be compared with the figures for the 

 genus, it will be found that those for the corresponding 

 columns differ, if at all, only "within narrow limits. Thus). 

 in case of Hippeastrwm the figure in the fjr.-t column 

 of this table and chart is ".'.S, while the figures for the 

 nine starches represented in this genus vary between 2 

 and 5; in the last column the figure is 12.8, while the 

 range for all of these starches is from 11 to 14. The sum 

 is 836, and the range from 7 IS to 925. The average is 

 31, and the range from 39 to 36. And so on with Iris 

 and Lilium. When, however, there are subgeneric 

 groups there may be as many types as there are groups, 

 as is well illustrated by instances referred to. 



Obviously, the method of differentiating genera, sub- 

 generic groups, species, hybrids, and varieties by such 

 a system has its limitations, not because of the failure 

 of the data p< /• se, hut because of the faultiness of the 

 method of formulating the data. This is manifest, for 

 instance, in Hippeastrum and Nerine, in which the data 

 as tabulated indicate very closely related trenera or even 

 subgenera, yet these genera, although belonging to the 

 same family, are well separated and are not confounded 

 by the botanist. When, however, the data are presented 

 in other forms, as in other tables and charts, tic genera 

 are a- markedly differentiated from each other, and the 

 members of each genus from each other, as they are by 

 tic data of toe e \ si emat ist. Finally, it is of interest 

 to note that in summing up these averages intermediate- 

 of the hybrid is not the rule, the tendency being 

 more frequently for the hybrid values to e, eed or fall 

 belovi ; : f the parents than to he intermediate. 



\vi r lge Temperatures of Gelatinization ( !om pari d 

 with the Average Reaction-intensities. 



ible B -'. Chart B 42) 



During the pi if the research it was found thai 



the temperature i E gelatinization bore varying relation- 



to the average reaction-intensities, as a whole, of 



at members of certain sets, different sets, and dif- 



