196 SCHOOL SCIENCE AND MATHEMATICS

This work demands not merely the technique of plant breed-ing, but it involves also the technique of cytology to discoverthe structural changes; and the technique of physics and ofphysiological chemistry to determine the conditions and sub-stances that are factors in the various processes. Perhaps oflargest significance is the fact that, just as the doctrine of evolu-tion broke up a static taxonomy, so this experimental work withinheritance is breaking up a static morphology, and a staticgenetics, encrusted with rigid definitions, and is making thesegreat fields dynamic.Those who wish to project the facts of inheritance and response

into the field of eugenics may find some fertile suggestions toconsider. If these two factors are involved in every result ofreproduction what is the contribution of each? Is the controlof inheritance the only problem of eugenics? Our present pic-ture of reproduction is something as follows. A fertilized eggincludes a wide range of possibilities. Inheritance determinesthe number and nature of these possibilities; for our possibilitiesare limited by those we have received. No one of us ever de-velops a tithe of his possibilities; in other words, our stock intrade is always much larger than we use. The parental selec-tion of possibilities may be no clue to our own; that is, we arenot necessarily doomed by the selection our parents have made,for they pass on to us possibilities they have never called upon.

If inheritance limits us only in the number and nature of ourpossibilities, what determines the selection? Here is where therole of response appears and the response follows what maybe called opportunity. The conclusion is, that while we mustsee to it that inheritance is as favorable as possible, it is evenmore important to see to it that every child shall have a stimulat-ing opportunity.

THE JUNEAU GOLD BELT.The large mining developments near Juneau, Alaska, have attracted at-

tention to the northern extension ,of the Juneau gold belt. Though rel-atively little productive mining has yet been done in that area, somedevelopments are under way. The region is heavily timbered and thereforedifficult to prospect. In spite of the difficulties detailed topographic andgeologic maps of this region have been made. The maps are published,together with a description of the geology and mineral resources, ina report entitled The Eagle River Region, Southeastern Alaska, by AdolphKnopf (Bulletin 50Q.), which may be procured on application to the Di-rector of the United States Geological Survey, Department of the Interior,Washington.