368 



APPLICATIONS OF RESULTS OF RESEARCHES. 



for instance, as has been referred to in the synthesis of 

 starch (see Publication 173, page 156), when six mole- 

 cules of formaldehyde are polymerized and condensed to 

 form dextrose. Moreover, it is to be assumed that the 

 molecular system consists of these three forms of mole- 

 cules in chemical combination, and therefore if the pro- 

 portions vary the system will vary in its properties. The 

 chief component of this system when water is in the form 

 of ice is (H 2 0) 3 and of steam (H 2 0), while in the form of 

 liquid water it is (H 2 0) 2 . 



Each of these forms of water is, therefore, a ternary 

 mixture of molecules in chemical combination, the pro- 

 portions of the three kinds of molecules differing, and 

 alterable in relation to changes in temperature and 

 pressure, and in the direction of the maintenance of 

 physico-chemical equilibrium. It is also probable that 

 there may be higher polymers, and that each polymer 

 may exist in more than one form, thus indicating a 

 further and by no means unimportant degree of plastic- 

 ity in stereochemic phenomena, especially in relation to 

 vital processes. Even the proportions of these molecules 

 in ice prepared under varied conditions are almost cer- 

 tainly different, inasmuch as some forms of ice are 

 heavier and other forms lighter than water, and as one 

 form crystallizes in the hexagonal system, another in 

 the tetragonal system, and another in the regular system. 



Further evidence of the plasticity of water is seen 

 in the variety of forms of snow crystals, all of which are 

 said to belong to the hexagonal system. It is easy to 

 account for these different forms if, as is indicated, the 

 proportions of these three kinds of molecules vary with 

 temperature; if water in vapor form in the clouds has 

 like eteam a maximum proportion of the (H 2 0) mole- 

 cules, and if cooling to the freezing-point brings about 

 (as the temperature falls) progressive changes in the 

 proportions of the molecules, and hence of the molecular 

 system, so that at any given temperature the composi- 

 tion of the system is different from that at any other 

 temperature; if these changes in proportions may be 

 further influenced by the rapidity of the fall of tempera- 

 ture, the velocity of the change not keeping pace with 

 the temperature change; and if crystallization may be 

 influenced by incidental conditions, as is manifested in 

 the variety of crystalline figures when ice forms on a win- 

 dow pane. It has recently been found that when con- 

 densation takes place in highly supersaturated ascend- 

 ing air, and the air temperature is much below freezing- 

 point, both snow crystals and rain-drops are formed. 

 If such plasticity is to be found in substances so simple 

 as water it seems that almost any conceivable degree is 

 to be expected in complex substances, such as the pro- 

 teins, fats, carbohydrates, and other organic metabo- 

 lites, and to the very ultimate degree in protoplasm. 

 The plasticity of proteins has been demonstrated in the 

 modifications of the hemoglobins in specific relationship 

 to the source ; and of carbohydrates in the starches in the 

 same respect, and especially in the diversified reactions 

 in which properties are elicited that are the same as 

 those of one or the other parent, or both parents, or 

 which are not exhibited by either parent, and which 

 are therefore peculiar to the hybrid, and in all the 

 phases of the reactions seem to be limited only by the 

 number of reagents. 



Having now in protoplasm a molecular system of 

 extreme complexity, affectibility, and plasticity, unceas- 

 ing changes in internal and external conditions and a 

 knowledge of the fundamentals of biochemistry such as 

 is indicated in preceding sections, it requires no more 

 effort of the imagination, than in the reactions of organic 

 substances generally, to picture the underlying factors 

 and processes that become expressed in the differences in 

 form, structure, and vital characteristics that are mani- 

 fested in variations, sports, fluctuations, and kindred phe- 

 nomena, and in individuals, varieties, species, and genera. 

 It seems that the mechanisms of Mendelian inheritance 

 and sex have striking analogies in the evolution of a and 

 ft forms of stereoisomers, as, for instance, in the case of 

 a- and /8-glucose, as was pointed out in the preceding 

 memoir, page 10. 



PROTOPLASMIC STEREOCHEMIC SYSTEM APPLIED TO 

 THE GENESIS OF SPECIES. 



The importance of hybridization in the genesis of 

 species has undoubtedly been greatly underestimated, 

 chiefly because of a false valuation that has been placed 

 upon intermediateness as a criterion of hybrids and the 

 belief that the hybrids between species are very commonly 

 infertile. But it seems obvious from the records of this 

 research that such characters of a hybrid as may be in- 

 termediate may be overshadowed by others, some of 

 which are the same as those of one or the other parent 

 or both parents, or developed beyond parental extremes, 

 or which may be peculiar to the hybrid. De Vrics, in 

 his exposition of the laws of mutation of Oenotkera, 

 states as follows : 



| 



"The mutations to which the origin of new elementary 

 species is due appear to be indefinite, that is to say, the changes 

 may affect all organs and seem to take place in almost every 

 conceivable direction. The plants become stronger (gigas) or 

 weaker (albida), with broader or with smaller leaves. The 

 flowers become larger (gigas) and darker yellow (ruprinervis), 

 or smaller (oblonga and scintillans) and paler (albida). The 

 fruits become longer (rubrinervis) or shorter (gigas, albida, 

 lata). The epidermis becomes more uneven (albida) or 

 smoother (Icevifolia); the crumples on the leaves either in- 

 crease (lata) or diminish (scintillans). The production of 

 pollen is either increased (rubrinervis) or diminished (scin- 

 tillans); the seeds become larger (gigas) or smaller (scintil- 

 lans), more plentiful (rubrinervis) or more scanty (lata). 

 The plant becomes female (lata) or almost entirely male 

 (brevistylis) ; many forms which are not described here were 

 almost entirely sterile, some almost destitute of flowers. 0. 

 gigas, 0. scintillans, 0. oblongata tends to become biennial 

 more than O. lamarckiana; and 0. lata tends to become less 

 so; whilst 0. nanella cultivated in the usual way scarcely ever 

 runs into the second year. This list could easily be extended, 

 but for the present it may suffice. To regard the new forms 

 from another point of view, some of them are fitter, some 

 unfitter, than the parent form and others neither the one nor 

 the other." 



In reference to 0. lamarckiana, he states that nearly 

 all organs and all characters mutate, and in almost every 

 conceivable direction and combination. The foregoing 

 quotation is of especial interest at the present juncture 

 because the data are applicable to hybrids, and as it seems 

 to have been satisfactorily established that these mutants 

 nrc actually hybrids. Moreover, when they are taken 

 in connection with the data quoted from Focke in 

 the Introduction, we have facts that arc in entire accord 

 with the results of the studies of the physico-chemical 

 properties of the starches. Again, Ipomcea sloteri, one 



