UEACTIOX-INTKNSITIKS WITH KACII ACKNT AND REAGENT. 



171 



were entirely gelatinized. In Narcissus tazetta grand 

 monarque, during the first 15 minute l< than 0.5 per 

 cent of the grain*, but 20 per cenl of the total starch, 

 were gelatinized, and during tin.' progress of the reaction 

 both curves rise, but the curve of the percentage of total 

 starch rises somewhat more rapidly than tin- other. In 

 certain of the charts this progressive separation i een, 

 as in Amaryllis belladonna (Chart D635) and Tritonia 

 pottsii (Chart D 651) ; in others, there i- for a time 

 separation, this being followed by approximation, as in 

 Hippeastrum titan (Chart 1) 636) and Hcemanthus puni- 

 ceus (Chart D 640) ; and in others, there i.s an early 

 marked separation followed in time by approximate 

 parallelism, as in Gladiolus tristis (Chart D650) and 

 Calanthe rosea (Chart 1)658), and so on with various 

 differences. 



While no two charts are identical sonic arc quite 

 similar, yet readily differentiated. Such similarity is apt 

 to be found in very closely related varieties and species — 

 for instance, in Hippeastrum til an, II. ossultan, and 

 //. deeones (Charts D636, D 637, and D 638), and in 

 Iris (Charts D 646, DC 17, and D648). Those of the 

 several species of /. ilium, differ markedly (Charts 

 D643, D644, and D645). Those of widely separated 

 species, such as Hcemanthus katherince and II. puniceus, 

 are decidedly different from each other, which species for 

 reasons as stated, probably represent subgeneric groups. 

 The same peculiarities are true in Iris, those of I. iberica 

 (Chart D646), /. trojana (Chart D 647 ) and /. cen- 

 ijiulli (Chart D 648) having a close general resemblance, 

 and markedly contrasted with the curves of the appa- 

 rently distantly related /. persica var. purpurea (Chart 

 1 ) 6 19), which curves are quite different from the former. 

 Gladiolus and Tritonia (Charts D 650 and D 651), wdiile 

 representing closely related genera and exhibiting at the 

 end of the 60-minute period the same percentages of 

 both total starch and entire number of grains completely 

 gelatinized, nevertheless present differences in the courses 

 of the curves that are quite definitely distinctive. 



In some of the charts it will be seen that there is an 

 early period of resistance of the starch to gelatinization. 

 This is manifest in some instances in the percentage of 

 completely gelatinized grains, but not in the percentage of 

 total starch gelatinized, as in Iris iberica and I. trojana 

 (Charts D 646 and D 647), and in Lilium chalcedonicum 

 (Chart D 645) ; in others, it may lie the reverse, as in 

 Narcissus tazetta grand monarque (Chart D 642) : and 

 in others, in both percentages, as in A maryllis bella- 

 donna (Chart D 635) and Hippeastrum titan (Chart 

 D 636). In other charts both curves may begin at once 

 to rise rapidly, but the percentage curve of total starch 

 rises more rapidly than the other, as in Hwmaullnis 

 puniceus (Chart D640), L. martagon (Chart D 643), 

 Musa arnoldiana (Chart D 654), and Miltonia vexillaria 

 (Chart D 656). In the different starches these changes 

 go on with varying rapidity and relationships, so that 

 by the end of the 5-minnte period not only may the 

 two curves of any given starch be well separated but their 

 courses may be quite different. Thus, the figures for the 

 percentages of total starch and number of grains com- 

 pleted gelatinized in 5 minutes in the above four species 

 are 33 and 65, 30 and 77, 30 and 86, and 27 ai 

 respectively. It is to be noted that while in the four cases 

 the percentages of the entire number of grains com- 



pletely gelatinized ai ame or nearly the same, the 



different. 

 'I'h,- i- iif diagnostic impot tan e it ind 



inherenl individual peculiarities of the several 

 The preceding odicate to what degree 



tin- reaction oi different starches with a given rea 

 may differ in tl ta 



entire number of grams compl tely gi I 

 the tendencies in general to sim 

 curves of closely related starches and to i trilies 



of distantly or unrelated starch 



\\ hen similarities are observed, as in the ver 

 related Hippeastrums, such peculiarity 

 in the reactioi ol thi same starches with other rea 

 for instance, in thi tic- with chloral h\ 



(Charts D 659, I) 660, and D 66] ) the threi 

 curves are closely alike, the type i< the sat 



is seen in the pyrogallic-acid reaction (I bai D 

 D 637, and D 638), but the p of the curves in the 



two reactions are different, owing to the distinctly I 

 reactivities of these starches with chloral hydrate. When, 

 however, the reactions of the starches of well-sepai 

 or unrelated species are studied it is found that I 

 may be the widest variations in the r la1 tps of the 



two curves, not only with different agent but also with 

 the same reagent, even to the extent that the p 

 of total starch gelatinized will give a type of curve 

 entirely different from that of the tage of grains 



completely gelatinized. Thus, examining the pyrogallic- 

 acid reactions of the various starches (Charts 1> 6 

 I) 658), it will be found that there is with fi 

 tious a well-marked tendency to separation of th 

 curves, and that in some instances the two cur. 

 not of the same type, as in Lilium chalet <!<inicum (i bait 

 D 645) and Iris trojana (Chart D647). In contrast 

 with this, in the chloral-hydrate tea lions (Charts 1» 659 

 to D 667) both curves tend to marked closeness in course 

 and hence to the same type. Comparisons of the p 

 gallic-acid and chloral-hydrate reactions of the same 

 starch bring out many interesting point-. For insta 

 in Amaryllis belladonna (Charts D 635 and D 662) in 

 the pyrogallic-acid reaction the two curves become v. 

 separated during their progress, the percentage of com- 

 pletely gelatinized grains ceases to increase after 30 

 minutes, but the quantity of gelatinized starch is mate- 

 rially being added to by the grains that are undergoing 

 partial gelatinization ; while in the chloral-hydrate reac- 

 tion the curves keep very close throughout. The most 

 marked difference between the reactions of the two rea- 

 gents is seen in the curves of the percentage of the entire 

 number of grains completely gelatinized, which differ 

 greatly, while the total p e curves differ compara- 



tively very little. In Hcemanthus puniceus (Charts 

 D 640 and D 664) the pyrogallic-acid and chloral-hy- 

 drate curves are of different types; and the cur., 

 both pairs of percentages tend to i loseness, mere particu- 

 larly the chloral-hydrate curves. In us tazetta 

 grand monarque ((hart- D 642 and D665) both pairs 

 are again different, not only from those of the prec 

 charts, but also from each other, and as markedly in the 

 latter as in the former case. 11 pairs 

 of curves are distinctly different, and while the two 

 curves in the pyrogallic-acid reaction tend to progressive 

 separation, these of the chloral-hydrate reaction tei 



