SUMMARIES OF THE HISTOLOGIC CHARACTERS, ETC. 



305 



pollen parent; in 7m three incline to the seed parent 

 and one to the pollen parent; and in Calanthe one in- 

 clines to the seed parent and one to the pollen parent. 

 In the quantitative reactions this absence of constancy 

 to one or the other parent is much more marked; thus, 

 in only Brunsdonna and Begonia do all of these chloral- 

 hydrate reactions tend to the seed parent ; but in no 

 genus do all of them incline to the pollen parent. Exam- 

 ining the different generic groups we note that in Hip- 

 peastrum in two hybrids the reactions incline to the seed 

 parent and in one to the pollen parent; in Hmnanthus 

 in one hybrid the reaction inclines to one as much as to 

 the other parent, and in the other to the seed parent; 

 in Crinum one inclines to the seed parent and two to the 

 pollen parent ; in Nerine one inclines to the seed parent 

 and four to the pollen parent; in Narcissus five incline 

 to the seed parent, six to the pollen parent, and two in- 

 cline to one as much as to the other parent ; in Lilium two 

 incline to the seed parent and three to the pollen parent ; 

 in Iris two incline to one as much as to the other parent, 

 and two incline to the pollen parent; and in Calanthe 

 one inclines to the seed parent and the other inclines to 

 one as much as to the other parent. Of exceptional 

 interest is the fact, several times noted, that in case of 

 any hybrid the qualitative and quantitative reactions 

 may or may not correspond in their parental inclinations. 

 It is certainly remarkable that with a given reagent the 

 qualitative reaction may correspond with that of the seed 

 parent and the quantitative reaction with that of the 

 pollen parent, or vice versa, and so on in other varied 

 relationships. 



The tendency in general to a ratio of approximately 

 2 : 1 in the qualitative reactions in their relations to the 

 seed and pollen parents is well marked. This ratio 

 varies from 4 : to 1 : 1, but in about half of the cases it 

 will be found to be as first stated. Totaling these rec- 

 ords, it will be seen that 62.8 per cent of these reactions 

 incline to the seed parent and 35.8 per cent to the pollen 

 parent, a ratio of 1.8 : 1. In other words, there is 

 approximately twice the tendency for the qualitative 

 reaction to be closer to the seed parent than to the pollen 

 parent. 



There is not a corresponding tendency to such a com- 

 mon ratio in the quantitative reactions, but to a marked 

 inconstancy. In the qualitative reactions the ratio is 

 always in favor of the seed parent ; but in the quantita- 

 tive reactions it may be in favor of either or of neither 

 parent. Thus, it is found that there may be a ratio 

 of 4 : 1 in favor of the seed parent, or one of 1 : 3 or 1 : 4 

 in favor of the pollen parent, and intermediate grada- 

 tions. Summing up these reactions, 44 per cent incline 

 to the seed parent and 40 per cent to the pollen parent 

 a ratio of approximately 1:1. In studying the quanti- 

 tative records the large number of reactions that are 

 recorded as being the same as those of both parents 

 should be taken into consideration, because had these 

 been shown to have had in each case, or even in most 

 cases, definite uniparental inclinations these ratios would 

 of course be subject to more or less modification. Nearly 

 all these reactions showed no difference from the parental 

 reactions because of gelatinization occurring with too 

 great a rapidity or slowness for differentiation. Modi- 

 fied strengths of reagents would doubtless have elicited 

 differences that are wholly obscured by very quick or 

 20 



slow reactions. It is, however, not probable that there 

 would be brought about any important change, as a 

 whole, in these ratios. Why the qualitative ratios should 

 be so different from the quantitative ratios is entirely 

 problematical, very interesting, and very suggestive of 

 stereochemic peculiarities of the starches. 



No feature of these records is more remarkable than 

 the reversal of the qualitative and quantitative reactions 

 of a given starch with a given reagent in their parental 

 inclinations. It is of importance to note that this phe- 

 nomenon is not peculiar to any starch or reagent, but is 

 common, and doubtless common to all starches and to all 

 reagents. With not a single starch was it found that 

 there was not such reversal; and with only four of the 

 reagents (strontium nitrate, barium chloride, and mer- 

 curic chloride) was reversal not recorded, the reason for 

 which is doubtless to be found in the small number of 

 qualitative reactions recorded with these reagents (four 

 reactions with the first, one with the second, and four 

 with the third). Not less remarkable than the reversal 

 of the reactions is the frequency with which this phe- 

 nomenon occurs, the percentages ranging from 6 in the 

 iodine reactions to as high as 50 in the cobalt-nitrate and 

 cupric-chloride reactions with the different starches. The 

 mean is 22.5, or close to one-fourth. 



TABLE E. 



