376 



NOTES AND CONCLUSIONS. 



become epecifioally female and others male. Moreover, 

 in addition to these sex hormones and hypothetical sub- 

 stances there are the influences of environmental con- 

 ditions which are effective in unknown ways. 



If, as seems manifest, there are species-types of 

 metabolism, if these types are undoubtedly modifiable by 

 environimental conditions, if these types give rise to 

 corresponding species-types of metabolites, and if these 

 metabolites have inherently the potemtialities of both 

 parents that can, as has been shown, be elicited in any 

 one or more of the six parent-phases by the selection 

 of the proper agent or reagent, it seems to follow, as a 

 corollary, that corresponding properties should be mani- 

 fested by sex-types. These statements suggest that in 

 artificial parthenogenesis and artificial fertilization the 

 selection of a proper agent or reagent may render it pos- 

 sible to give rise to eitifier siex, or before or after develop^ 

 ment has begun, to gynandromorphism. In a word, from 

 present knowledge and indications (and all that they 

 imply), species, parthenogenesis, fertilization, sex, sec- 

 ondary sex characters, and sex control are problems of 

 physical chemistry. 



Intermediateness as a Ceiteeion of Hybeids. 



Whether or not intermediateness is a criterion of hy- 

 brids depends upon the sense in which these two terms are 

 used — that is, whether or not intermediateness is to be 

 taken as meaning mid-intermediateness, and where the 

 line is to be drawn where intermediaieness in either 

 a broad or a narrow sense is or is not a criterion. Some 

 authorities, as is evident by references in the introduc- 

 tion, look upon intermediateness in the sense of mid- 

 intermediateness or " exact intermediateness," and upon 

 this developmental peculiarity as being a criterion when 

 all or nearly all of the characters of the hybrid are mid- 

 intermediate ; but it is manifest that such a conception 

 is not justified by literature and is untenable. Viewing 

 intermediateness from a broad point of view — ^that is, to 

 include all characters which show stages of character 

 development between those of the parents, it is an open 

 question as to whether a character that is intermediate 

 but exhibits almost identity with that of one parent 

 should be classified as intermediate or as being the same 

 as the character of the parent. Many of both the starch- 

 reaction and the tissue characters that herein have been 

 classified as intermediate have been so close in their 

 development to the parent characters that it is question- 

 able if they should not have been assigned to the charac- 

 ters that are the same or practically the same as those 

 of the parent. Then again, what percentage of inter- 

 mediate characters must be intermediate to justify the 

 application of the term criterion? Among the 1,018 

 starch reactions, 236 were recorded as being intermediate, 

 while 53 were mid-intermediate. Among the 959 macro- 

 scopic and microscopic tissue characters 415 were inter- 

 mediate, and 160 were mid-intermediate. The differences 

 in the figures of the starch and tissue records are prob- 

 ably due chiefly to differences in both number and kind of 

 material. Moreover, the percentages of characters devel- 

 oped beyond parental extremes are very high, those in the 

 starch reactions exceeding (nearly doubling) the per- 

 centage in intermediate characters ,(40.6: 23.2), and in 

 the tissue characters being almost as high as the latter 

 (39 : 43.2) . It seems from these data that if intermedi- 



ateness is a criterion, development in excess and deficit 

 of parental extremes may or should have an equal or 

 greater degree of importance, and even a far greater value 

 if only mid-intermediate characters are taken as the 

 criterion. 



Geemplasm a Steeeochemic System. 



The recognition that the germplasm is a stereochemio 

 system that ia characterized by the kinds and arrange- 

 ments of its stereoisomers in the three dimensions of 

 space; that it is of great complexity, impressionability, 

 and plasticity; that it presumably possesses potentially 

 the characters and character-phases of the parent; that 

 the germplasms of the sexes are different, varying in 

 plasticity, etc.; and that in normal fecundation there 

 occurs a union of the two sex systems with interactions, 

 rearrangements, and combinations, and therefore a new 

 physico-chemical state is developed that possesses the 

 potentialities of both sexes; that stereoisomerides are 

 readily transmuted with attendant change of properties, 

 and that the directions and propensities of the reactions 

 are determined by peculiarities of the compounds and 

 attendant conditions; and, finally, that we have, in a 

 word, in the germplasm a form of protoplasm that must 

 like all colloidal substances be studied upon the basis 

 of physical chemistry, opens up a unique and promising 

 field for investigation of the laws that determine organic 

 growth, form, and function. 



Applications to the Explanations op the Oc- 



CUEEENCE of VaEIATIONS, SpOETS, FlITCTUA- 



tions and the Genesis of Species. 



The characters of the germplasm and of protoplasm, 

 and incidentally the extraordinary plasticity of the starch 

 molecule, as set forth by the results of this research, 

 seem readily to induce clear conceptions of the mechan- 

 isms that underlie variations, sports, fluctuations, Men- 

 delism, reversions, monstrosities, etc., and also the genesis 

 of strains, subspecies, and species by gradual and progres- 

 sive changes and ultimate fixation. And it also seems, 

 from the data presented in conjunction with biological 

 literature, that we have all of the postulates that are 

 necessary to warrant the assumption that probably the 

 chief method in the genesis of species is by hybridization. 



Scientific Basis foe Classification of Plants 

 AND Animals and foe the Study of Peoto- 



PLASM. 



The discovery of the existence of highly specialized 

 stereoisomers that are specifically modified in relation to 

 genera, species, varieties, etc., has brought to light one 

 of the most extraordinary phenomena of living matter, 

 and it not only gives us a strictly scientific basis for the 

 classification of all forms of life, but also leads us to 

 the varying constitutions of protoplasm of the same and 

 of different organisms, and to the differences in vital 

 phenomena that are dependent upon these variations. 

 The dictum set forth in the hemoglobin investigation 

 that "vital peculiarities may be resolved to a physico- 

 chemical basis " has been most substantially supported, 

 and it may be safely predicted that important and even 

 epochal advances in the elucidation of many of the great 

 problems of biology will be made in the near future 

 along such or closely related lines of investigation as 

 have been pursued in these researches. 



