REACTION-INTENSITIES WITH EACH AGENT AND REAGENT. 



173 



the sources of fallacy by increasing the number and 

 changing the concentration of the reagents and modify- 

 ing the standard of values in accordance with the abscis- 

 sas here used. Notwithstanding the crudities of the 

 methods adopted and the fallacies introduced in the 

 formulation of the composite charts in the former 

 memoir the following was rendered apparent : That the 

 reactions of members of a genus constitute a well-defined 

 group, the mean of the character-values constituting a 

 distinct generic type, this type tending to be similar to 

 the types of very closely related genera and dissimilar 

 to the types of distantly related or unrelated genera ; 

 that the reactions of different species of a genus yield 

 curves that tend to be closely in conformity with the 

 generic type of curve, but when there are representatives 

 of subgenera or similar generic subdivisions there may 

 be departures or aberrations from this generic type so 

 that there may be as many subgeneric or group types as 

 there are subgenera or subgeneric groups ; that the reac- 

 tions of varieties of a species yield curves that very closely 

 correspond with those of the species ; and that the generic, 

 subgeneric, and species differentiations are in general 

 in close accord with established botanical data. The re- 

 sults of the present research are in harmony with those 

 of the preceding investigation, but some unexpected 

 variations have been found, especially in the extent of 

 certain generic and subgeneric differentiations which will 

 be referred to here with sufficient detail. 



Taking up first those genera which arc best repre- 

 sented by s]>ecies and varieties, but in which there are 

 not included subgeneric or similar generic group repre- 

 sentatives, such as Hippeastrum (Charts E 2, E 3, and 

 E 4), Ncrine (Charts E 10, E 11, and E 12), Narcissus 

 (Charts E 13 to E 24, inclusive), and Lilium (Charts 

 E25 to E 2!), inclusive), it will be apparent upon 

 even superficial examination that the starches of the 

 varieties or species, or of both varieties and species, of 

 each genus have curves that are in general very similar 

 in form and that the type form of the curve in each genus 

 is different from that of any other, and so markedly 

 so that the curves of the members of one genus could 

 not be confounded with those of another any more than 

 could the plants themselves. It will also he noted that 

 when the starches are from very closely related plants, 

 as in the Hippeastnms, the curves are very closely alike, 

 while in Ncrine and Narcissus, respectively, where there 

 are instances of both botanical closeness and separation, 

 the variations from the mean or the generic type of 

 curve tend to be more and more marked as the repre- 

 sentatives of the genus are botanically farther separated. 

 The curves of Lilium, while yielding a generic type very 

 different from the Ilippeasirum, Nerine, and Narcissus 

 types, are of little usefulness in the differentiation of 

 the various members of the genus represented because 

 of the very rapid gelatinization of the starches with 

 nearly all of the reagents. In order to satisfactorily 

 differentiate these starches reagents of such modified 

 strengths must be used as will render gelatinization very 

 much less rapid, and probably additional reagents may 

 be necessary. In other genera studied, where there are 

 only the two parental and the hybrid representatives of 

 the genus, as in Gladiolus (Chart E34), Triton in 

 (Chart E35), Riclmrdw (Chart E40), Musa (Chart 

 E41), Plating (Chart E42), Miltonia (Chart E43), 



Cyinbidium (Chart E44), corresponding peculiarities 

 will be found, although in Gladiolus and Tritonia, closely 

 related genera, the curves are so much alike as to indi- 

 cate different species rather than different genera. There 

 is also much resemblance between the Amnri/llis and 

 Phaiti-s charts which represent very widely separated 

 genera, but this singular peculiarity will be referred to 

 particularly later on. In the Amaryllis-Brunsvigia reac- 

 tions (Chart El), where there is bigeneric representa- 

 tion, the curves are quite different. 



When genera are represented by subgenera or sub- 

 generic groups, as in Hcemanthus (Chart EG), Crinum 

 (Charts E 7, E 8, and E9), Iris (Charts E 30, E 31, 

 E 32, and E 33), and Begonia (Chart E 36), the curves 

 of the subgeneric representatives may differ not only 

 markedly but to even a much more marked degree than 

 the curves of different genera generally of the same 

 family a most curious and as yet inexplicable phe- 

 nomenon. In Hcemanthus the curve of II. puniceus is so 

 variant in comparison with those of H. l-afJicrincu, H. 

 magnificus, and both hybrids that it seems that this spe- 

 cies must be separated botanically sufficiently far from 

 the other two to be regarded as belonging to a different 

 subgenus, although this differentiation may not have been 

 recognized by the systematist. In Crinum the curves of 

 the representatives of the hardy and tender forms (C. 

 moorei and C. longifolium, hardy ; C. zeylanicum, tender) 

 differ so markedly as to suggest members of different 

 genera. In Iris, in the first three sets (Charts E 30, 

 E 31, and 10 32), the reactions of rhyzomatous forms are 

 represented, and it will be seen that all of the curves 

 conform closely to a common type ; but in the fourth set 

 (Chart E33) the reactions arc of tuberous forms, all 

 three curves conform with great closeness to a common 

 type, and they all differ materially from the rhyzomatous 

 type, and in fact so different are they that they would 

 certainly not in the present stages of the investigation 

 be recognized as belonging to the same genus. In Bc- 

 i/niiia there is found an even more remarkable instance 

 of subgeneric differentiation in the curves of the tuberous 

 and semituberous forms, the former being represented 

 by four garden varieties and the latter by B. socoimna, 

 a very exceptional and isolated species of the genus. 

 Comparing the curves of these charts (Charts E 36 to 

 E 39) it will be seen that the curves of the tuberous 

 forms are in close conformity to a common type, while 

 the curve of B. socotrana is so very unlike the curves of 

 the former in a large number of the reactions with the 

 chemical reagents as to suggest anything but generic 

 relationship to the tuberous forms. Unfortunately, the 

 number of reactions of the latter were with a single ex- 

 ception very limited, but the curve of the reactions of B. 

 siin/li 1 rrinisoii' srarlct (Chart E 3(>) can with perfect 

 safety be taken as very closely typifying the curves of 

 the others. 



The Amaryllis and Pliaius curves (Charts E 1 and 

 E42), while representing wholly unrelated and widely 

 separated genera, give the impression of curves of closely 

 related genera or even of species of a genus ; in fact, the 

 resemblance is much closer than that of related genera 

 here represented, as, for instance, of Amaryllis and Bn/ns- 

 rigia (Chart E 1), of Pliaius and Afilfonia (Charts E -12 

 and E43), or of PJiaius and Cymbidium (Charts E 42 

 and E44). While there is some resemblance between 



