364 



APPLICATIONS OF RESULTS OF RESEARCHES. 



THE GERMPLASM A STEREOCHEMIC SYSTEM. 



The Germplasm is a Stereochemic System that is, a 

 Physico-chemical System Particularized by the Char- 

 acters of its Stereoisomers and the Arrangements of 

 its Components in the Three Dimensions of Space. 



If during the progress of development there arise 

 the multiple forms of differentiated protoplasm that are 

 represented in the nerve cells, muscles, glands, etc., 

 which exhibit such diversity of form, functions, com- 

 position, and products, each part being correlated to 

 other parts by the agency of tissue products, it is logical 

 to assume that in the development of the ovaries and 

 testicles these organs have been so specialized as to en- 

 dow them with the attribute of producing a form of 

 protoplasm that embodies in a germinal state the funda- 

 mental peculiar stereoisomerides and the peculiar ar- 

 rangements or phases of the associated proteins, fats, 

 carbohydrates, and other substances which inherently 

 characterize the organism; and, moreover, that owing 

 to the influences of the products of activity of the vari- 

 ous tissues upon these organs, such changes in the organ- 

 ism as give rise to acquired characters may through the 

 actions of modified or new tissue products or foreign 

 substances affect the operations of these organs and thus 

 alter the germplasm and consequently become mani- 

 fested in some form in the offspring. The ovule in its 

 incipiency is conceived to be comparable to a complex 

 unequilibrated solution in which changes go on until 

 the attainment of full development, at which time it is 

 equilibrated and remains inactive because of the absence 

 of some disturbing influence, but in which energy-reac- 

 tions may be initiated physically, mechanically, or chem- 

 ically, and proceed according to definite physico-chemi- 

 cal laws in definite directions to a definite end. For 

 instance, when a solution of boiled starch and diastase 

 is at a temperature below the minimal of activity and the 

 temperature is raised, causing immediate developmental 

 activation ; or when the equilibrated molecules of nitro- 

 glycerine are exploded by percussion ; or when an equili- 

 brated maltose-dextrose-glucase solution is rendered 

 active by dilution with water. 



The nature of the germplasm or transmissive material 

 that serves as the bridge of continuity between parents 

 and offspring has been the subject of speculation from 

 time immemorial. Such hypotheses and theories as have 

 been advanced have had reference almost wholly to its 

 physical constitution or ultimate morphological struc- 

 ture. Most of them are micromcric, that is, they hold 

 that the germplasm is made up of an infinite number of 

 discrete ultramicroscopic particles which are endowed 

 with both determinate structural and vital attributes. 

 A considerable degree of ingenuity has been displayed in 

 thoir formulation. Thus, we have the "organic mole- 

 cules" of Buffon, the "microzymes" of liechainp, the 

 " life units " of Spencer, the " plastidules " of Maggi, 

 the "bioplasts" of Altmann, the " stirps " of Galton, 

 the " gemmules " of Darwin, the " biophors " of Weis- 

 mann, the "pangens" of DeVries, etc., each author 

 attributing to the units certain inherent peculiarities. 

 To the foregoing might be added particularly the con- 

 ceptions that belong to the chemical category, such as the 

 " cheniism " of Le Dantec and the " physico-chemical " 

 theory of Delage. Some of these conceptions are so fan- 



ciful in the light of modern science as to be unworthy of 

 more than passing consideration, while none of them'has 

 led anywhere beyond the field of speculation and reason- 

 ing. Even the very recent and extremely interesting 

 and important additions to our knowledge of the histo- 

 logical phenomena of the developing ovum, especially 

 of the chromosomes, have not taken us appreciably nearer 

 the ultimate constitution or mechanism of the germ- 

 plasm, or even to the nature of the reactions which occur 

 immediately antecedent to and cause the formation of 

 the chromosomes. 



A theory to be ideal must not only have as its basis 

 well-defined principles that are consistent with facts, 

 but also be capable of substantiation by laboratory in- 

 vestigation. Given as the basis of scientific study a 

 germplasm that has inherently the power of develop- 

 ment, that is in the form of a stereochemic system that 

 is peculiar to the organism, that is highly impression- 

 able to stimuli, and that has the marked plasticity 

 inherent to organic colloidal matter, we have all the 

 postulates that are needed as a foundation upon which, 

 according to the laws of physical chemistry, can be built 

 a logical explanation of the essential fundamental ele- 

 ments of the mechanism of heredity. 



The inherent potentiality that determines the de- 

 velopment of the egg along a line of definite sequential 

 processes must be recognized as being common to Iwth 

 animate and inanimate matter and subject to the same 

 laws, so that the phenomena of living and dead matter 

 are inseparably linked and reciprocally explanatory. The 

 typical condition of matter of definite composition is crys- 

 talline, and the crystalline form is the result of develop- 

 ment that becomes manifested in a separation and orderly 

 and progressive arrangements of components in the three 

 dimensions of space. Having a homogeneous solution 

 of various selected crystalline substances of appropriate 

 chemical composition and constitution, and given con- 

 ditions attendant to crystallization, the successive stages 

 of crystalline development will proceed along fixed and 

 definitely recognized lines, and the interactions and 

 interaction-relationships between the various substances 

 constituting the physico-chemical mechanism become 

 obvious to a greater or less extent in the peculiarities 

 of form, composition, and other properties of the crys- 

 tals. Having in the germplasm an analogous physico- 

 chemical system, but one which is markedly different 

 especially because of its organic and colloidal character 



and infinitely greater molecular complexity and s ii- 



tivity, the phenomena of development likewise proceed 

 in conformity with the same laws along definite lines. 

 but they are for perfectly manifest reasons more com- 

 plex and varied, more difficult of analysis, and neces- 

 sarily in many very important respects quite different. 

 Each step in this orderly development leads not merely 

 to changes of the physico-chemical mechanism by the 

 modification, rearrangement, or splitting off of com- 

 ponent parts, but also to alterations which automati- 

 cally determine the characters of the next succeeding 

 step, and so on to the establishment of physico-chemical 

 equilibrium and the consequent termination of the 

 reactions. 



In living matter the chemical processes are depend- 

 ent to a preeminent degree upon en/ymes that are 

 formed by the different kinds of protoplasm to serve as 



