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\"Schon bei Aristoteles und Plinius finden wir einige Beispiele von Regeneration erwähnt. Indessen wurde erst durch die Aufsehen erregenden Beobachtungen und Experimente von Abraham Trembley die allgemeine Aufmerksamkeit der wissenschaftlichen Welt auf diesen Gegenstand gelenkt. Wie bei so vielen großen Entdeckungen spielt auch hier der Zufall eine gewisse Rolle. Trembley bekam einige Exemplare eines Süßwasserpolypen, Hydra, in die Hände, die ...

Excerpt from Heredity and Sex What I most fear is that in thus attempting to for mulate some Of the difficult problems of present-day interest to zoologists I may appear to make at times unqualified statements in a dogmatic spirit. I beg to remind the reader and possible critic that the writer holds all conclusions in science relative, and subject to change, for change in science does not mean so much that what has gone before was wrong as th...

Excerpt from The Mechanism of Mendelian Heredity We have tried to bring the book up to date not only by adding here and there throughout the text the latest results on the subject, but also by adding two entirely new chapters, and new maps of the best known mutant factors. Much new material has been added to the chapter on sex, the chapter on selection has been largely rewritten. The new chapters are one on heredity in Protozoa, and one on mu...

Excerpt from The Physical Basis of Heredity That the fundamental aspects of heredity should have turned out to be so extraordinarily simple supports us in the hope that nature may, after all, be entirely approach able. Her much-advertised inscrutability has once more been found to be an illusion due to our ignorance. This is encouraging, for, if the world in which we live were as complicated as some of our friends would have us believe we mig...

Excerpt from Evolution and Adaptation The adaptation of animals and plants to the conditions under which they live has always excited the interest, and also the imagination, of philosophers and scientists, for this relation between the organism and its environment is one of the most characteristic features of living things. The ques tion at once suggests itself: How has such a relation been brought about? Is it due to something inherent in th...

Excerpt from Experimental ZoologyPhysiology has from the beginning made use of the method of experiment, and with notable success. Morphology has, up to the present time, followed mainly the historical and descriptive methods, although striking exceptions could be cited. While the historical study of zoology must always remain a legitimate field for activity, as human history has been a time-honored study, yet there can be little doubt that th...

Excerpt from Sex-Linked Inheritance in DrosophilaFurrowed Additional data for yellow, white, vermilion, and miniature.New data contributed by A. H. Sturtevant and H. J. Muller Summary of the previously determined cross-over values Summary Of all data upon linkage of gens in chromosome I.About the PublisherForgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.comThis book is a reproduction of...

Excerpt from A Critique of the Theory of Evolution Occasionally one hears today the statement that we have come to realize that we know noth ing about evolution. This point of View is a healthy reaction to the over-confident belief that we knew everything about evolution. There are even those rash enough to think that in the last few years we have learned more about evolution than we might have hoped to know a few years ago. A critique theref...

Excerpt from The Development of the Frog's Egg: An Introduction to Experimental Embryology Polar bodies and fertilization Extrusion of the First Polar Body and Egg-laying. The Jelly of the Egg, and the Second Polar Body. Entrance of Spermatozoo'n and Copulation of Pronuclei. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an im...

Excerpt from Regeneration Tms volume is the outcome of a course of five lectures on Regeneration and Experimental Embryology, given in Columbia University in January, 1900. The subjects dealt with in the lectures are here more fully treated and are supplemented by the discussion of a number of related topics. During the last few years the prob lems connected with the regeneration of organisms have interested a large number of biologists, and ...

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