AMARYIAIS — ^BRUNSVIGIA — ^BRUNSDONNA. 



39 



Do the properties of Brunsdonna tubergeni, Brunsdonna 

 sandercs alba, and Brunsdonna sandera indicate that 

 these hybrids are the offspring of the same cross or of 

 reciprocal crosses; and (2) what are the indications 

 of the probable parentage of Amaryllis parkeri alba? 



The starch of Brunsdonna tubergeni has in compari- 

 son with the starch of B. sanderce alba and B. sanderw 

 certain properties that are closely similar or identical 

 and others that are more or less markedly dissimilar, 

 the latter much predominating. The grains of the for-- 

 mer are more irregular, and more slender and elongated ; 

 the hila are less distinct; the lamellae are more distinct, 

 more often coarse, and more often irregular ; the grains 

 are larger. In the polariscopic properties there are not 

 any conspicuous differences except that the figures tend to 

 be more irregular. In the iodine reactions the coloration 

 is distinctly less. In the aniline reactions with both 

 gentian violet and safranin the coloration is more 

 marked. In most of the foregoing instances the starch 

 of B. tubergeni does not differ more from the starches 

 of B. sanderw alba and B. sanderce than do the latter 

 from each other. In the temperatures of gelatinization 

 the figure for B. tubergeni is 64.76°, or a difference 

 approximately of 7.5° less than the temperatures of 

 the parental starches, these being 72.7° and 71°, re- 

 spectively. The temperatures for B. sanderw alba and 

 B. sanderw are 72.25° and 72.75°, respectively. It will 

 be noted that while the temperature for the parental 

 starches differ only 1.7°, that of B. tubergeni differs 

 from that of the pollen parent {A. belladonna) 7.94°, 

 and from that of the seed parent (B. josephinw) 6.24° ; 

 and that the temperatures for B. sanderw alba and B. 

 sanderw and their parents differ very little, mostly within 

 the narow limits of error of experiment. The very low 

 temperature for B. tubergeni on the one hand and the 

 marked closeness of all of the temperatures for B. san- 

 derw alba and B. sanderw and their parents on the 

 other indicate quite conclusively that B. tubergeni and 

 B. sanderw alba must have arisen from reciprocal crosses. 

 This conclusion is substantiated by the records (not- 

 withstanding their limitation) of the reactions with 

 chemical reagents. The reactions of all of the starches 

 with sidphuric acid occur with such rapidity that no 

 satisfactory differentiation is possible, but with both 

 potassium iodide and sodium hydroxide there are marked 

 and distinctly diagnostic differences. In reactions with 

 potassium iodide the starch of B. tubergeni exhibits a 

 somewhat higher reactivity than the starch of either 

 parent, while on the other hand the starches of B. sanderw 

 alba and B. sanderw show very much lower reactivities, 

 not nearly so much of the latter being gelatinized at the 

 end of an hour as there is in case of the B. tubergeni 

 and parental starches in 5 minutes. It is also to be 

 noted that during the progress of gelatinization the 

 curves of B. sanderw alba and B. sanderw tend to pursue 

 the same course, they being separated at and after the 

 5-minute interval by about 10 points. In the sodium 

 hydroxide reactions similar results are recorded, the 

 reactivity of the starch of B. tubergeni being very high 

 and closely corresponding to the reactivities of the 

 parental starches, but slightly higher than either, while 

 the reactivities of the starches of B. sanderw alba and 

 B. sanderw are both moderate, the reactivity of the former 

 being distinctly lower than that of the latter. 



There were studied in this research three groups of 

 parental and hybrid starches in each of which were in- 

 cluded two hybrids of the same cross, and it is of inter- 

 est to note to what degrees in general the members of each 

 pair compare with each other and with their parents 

 and how these peculiarities compare with those of the 

 Brunsdonnae hybrids and their parents. Examining first 

 the temperatures of gelatinization and taking up the 

 Nerine crispa-elegans-dainty maid-queen of roses group 

 (page 165) it wili.be seen that the temperature of the hy- 

 brids differ only 1.3° and that they are iatermediate 

 between the parental temperatures, which latter differ 

 5.2°; in the Nerine bowdeni^sarniensis var. corusca 

 major-giantess-abundance group the temperatures of the 

 hybrids differ 3.35° and both are lower than either of the 

 parental temperatures, these differing 3.9°; and in the 

 Narcissus poeticus-poeticus poetarum-poetiaas herricJc- 

 poeticus dante group the temperatures of the hybrids 

 differ 2°, that of one being intermediate between the 

 parental temperatures and the other practically the same 

 as that of the seed parent, while the parental tempera- 

 tures differ 5.5°, that of the seed parent being the higher. 

 The temperatures of each of these pairs of hybrids keep 

 close together and close to the temperatures of the 

 parents, as in the case of Brunsdonna sanderw alba and 

 B. sanderw, with wider variations in the former than in 

 the latter, but there is no suggestion of a wide departure, 

 such as is found in B. tubergeni, this latter indicating 

 either difference in parentage or in the direction of the 

 cross from that of the other Brunsdonna. 



In the reactions of the members of these groups with 

 potassium iodide and sodium hydroxide corresponding 

 characteristics have been recorded, that is, that the two 

 starches of each group show close reaction-intensities. 

 In the potassium iodide reactions of the Nerine crispa- 

 elegans-dainty maid-queen of roses group, those of the 

 hybrids are very much alike and, on the whole, inter- 

 mediate between those of the parents ; and in the Nerine 

 boivdeni-sarniensis var. corusca major-giantess-abundance 

 group, while those of the hybrids are low and differ dis- 

 tinctly, at least one and probably both tend to interme- 

 diateness, and one takes more after the seed parent and 

 the other more after the pollen parent. In the sodium- 

 hydroxide reactions, in the first group those of the hy- 

 brids are not only very close but also close to those of 

 the parents ; and in the second group those of the hybrids 

 are very close and lower than those of the parents. It 

 will be seen that in the reactions of each of the several 

 pairs of hybrids there are no such departures of the 

 reactions of each of the couples as are observed in the 

 case of Brunsdonna Uibergeni compared with B. sanderw 

 alba and B. sanderw. Prom the description of B. tuber- 

 geni this hybrid is more closely related in its properties 

 to Brunsvigia josephina than to Amaryllis belladonna, 

 while the data of B. sanderw alba and B. sanderw indi- 

 cate that, on the whole, both of these hybrids show a 

 closer relationship to A. belladonna than to B. joseph- 

 ina — in other words, in each case the hybrid is more 

 closely related to the seed parent. 



These data also give a clue as to the probable origin 

 of Amaryllis parkeri alba. The starch of this plant 

 throughout the histologic and polariscopic properties 

 and the iodine and aniline reactions, with rare exceptions, 

 exhibits a much closer relationship to Brunsdonna son- 



