viii editor's note 



apparatus, has been added as representative of the important 

 new methods. Still it is well for the student to review the 

 older methods, particularly the description of the use of the 

 Pettenkoffer tubes which are by no means antiquated. 



The emphasis which the author has placed on his "theory of 

 connection" is apparently justified by the central position occu- 

 pied by the problem of chemical relationships between the two 

 phases of respiration. It is in this field of the chemical aspects 

 of the subject that Kostychev is particularly well qualified to 

 write, and that the most work needs to be done. 



A difficult problem in all translation of material involving 

 the Russian workers is the matter of transliteration of proper 

 names. It has seemed best in this case to take the spelling as 

 given in the German text, except for the name of the author of 

 this book wherever it occurs in the text, the form Kostytschew 

 being kept in the citations. This decision is based largely on 

 the difficulty of determining the exact form of all the Russian 

 names as used in the original works, while for citations it is 

 customary to copy the author of papers in French or German as 

 given in such papers. The pronunciation can usually be 

 determined from the form of the word used in the German text, 

 the greatest difficulty being with the letter u> which is equivalent 

 to V in English. 



The form of citation is a condensation of that used by the author. 

 It uses a Roman numeral in parentheses (followed by a period) 

 for a series number, a bold-face Arabic numeral (followed by a 

 colon) for the volume number, an Arabic numeral in ordinary 

 type (followed by a period) for the first page of the article 

 cited, and an ordinary Arabic numeral for the year of publica- 

 tion. When an article or series of articles occurs at several 

 points in the same volume, the first-page numbers are separated 

 by commas. In the case of the editorial notes and matter in 

 brackets, both the first and last page of the citation are usually 

 given, separated by a dash. This might have been done for 

 most of the author's citations but it was felt that the additional 

 information was not important enough to warrant the extra 

 effort and space. 



