PREFACE 



It seemed desirable that the reader should be spared an 

 undue amount of repetition, and for this reason a number 

 of publications are omitted from this collection, and those 

 printed are in many cases shortened. Among the papers 

 which have been omitted are the preliminary notices and all 

 those papers of which I am not the sole author. Occasion- 

 ally I have made additions in the form of footnotes. Such 

 footnotes have always been marked by the addition of [1903] 

 at the end. 



Only a small number of these papers appeared originally 

 in English, namely, VII, XXI, XXVI-XXXV, and XXXVII. 

 The other papers were translated from the German by Pro- 

 fessor Martin H. Fischer, to whom I wish to express my 

 sincere thanks. The credit as well as the responsibility for 

 the translation belongs entirely to him. In the reading of 

 the proof I was assisted by Dr. Fischer. Dr. Rogers, Dr. 

 Bullot. and Dr. Bancroft. Mr. Rogers made the index for 

 the first volume. To all these gentlemen my thanks are due. 



JACQUES LOEB. 



BERKELEY, CALIFORNIA, 

 October 14, 19U4. 



