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SCIENCE 



[N. S. Vol. XL. No. 1036 



C. The Oermplasm a Stereochemic System, 

 that is, a Physico-chemical System that is 

 Particularized hy the Characters of its 

 Stereoisomers and the Arrange- 

 ments of its Components in the 

 Three Dimensions of Space 

 If during tlie progress of development there 

 arise the multiple forms of differentiated pro- 

 toplasm that are represented in the nerve 

 cells, muscles, glands, etc., which exhibit such 

 diversity of form, functions, composition 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 endow them with the 

 attribute of producing a form of protoplasm 

 that embodies in a germinal state the funda- 

 mental peculiar stereoisomerides and the pecu- 

 liar arrangements or phases of the associated 

 proteins, fats, carbohydrates and other sub- 

 stances which inherently characterize the 

 organism; and, moreover, that owing to the 

 influences of the products of activity of the 

 various tissues upon these organs, such changes 

 in the organism as give rise to acquired char- 

 acters 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 

 manifested in some form in the offspring. The 

 ovule in its incipiency is conceived to be com- 

 parable to a complex unequilibrated solution 

 in which changes go on until the attainment of 

 full development, at which time it is equili- 

 brated and remains inactive because of the 

 absence of some disturbing influence, but in 

 which energy-reactions may be initiated phys- 

 ically, mechanically or chemically, and proceed 

 according to definite physico-chemical laws in 

 definite directions to a definite end. As, 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 equilibrated maltose-dextrose-maltase solu- 

 tion is rendered active by dilution with water. 



The nature of the germplasm or transmis- 

 sive material that serves as the bridge of con- 

 tinuity between parents and offspring has been 

 the subject of speculation from time immemo- 

 rial. Such hypotheses and theories as have 

 been advanced have had reference almost 

 wholly to its physical constitution or ulti- 

 mate morphological structure. Most of them 

 are micromeric, that is, they hold that the 

 germplasm is made up of infinite number of 

 discrete ultramicroscopic particles which are 

 endowed with both determinate structural and 

 vital attributes. A considerable degree of in- 

 genuity has been displayed in their formula- 

 tion. Thus, we have the " organic molecules " 

 of Buffon, the " microzymes " of Bechamp, the 

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

 Maggi, the " bioplasts " of Altmann, the 

 " stirps " of Galton, the " gemmules " of Dar- 

 win, the " biophors " of Weismann, the 

 " pangens " of DeVries, etc., each author 

 attributing to the units certain inherent pecu- 

 liarities. To the foregoing might be added 

 particularly the conceptions that belong to the 

 chemical category, such as the " chemism " of 

 LeDantec and the " physico-chemical " theory 

 of Delage. Some of these conceptions are so 

 fanciful in the light of modern science as to 

 be unworthy of more than passing considera- 

 tion, while none of them has led anywhere be- 

 yond the field of speculation and reasoning. 

 Even the very recent and extremely interest- 

 ing and important additions to our knowledge 

 of the histological phenomena of the develop- 

 ing ovum, especially of the chromosomes, have 

 not taken us appreciably nearer the ultimate 

 constitution or mechanism of the germplasm, 

 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 con- 

 sistent with facts, but also be capable of sub- 

 stantiation by laboratory investigation. Given 

 as the basis of scientific study a germplasm 

 that has inherently the power of development; 

 that is in the form of a stereochemic system 

 that is peculiar to the organism ; that is highly 

 impressionable to stimuli; and that has the 



