SCIENCE 



A WEEKLY JOURNAL DEVOTED TO THE ADVANCEMENT OF SCIENCE, PUBLISH- 

 ING THE OFFICIAL NOTICES AND PROCEEDINGS OF THE AMERICAN 

 ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE. 



NEW SERIES. VOLUME XX. 



JULY-DECEMBER 1904. 



I'lObSS' 



NEW YORK 



THE MACMILLAN COMPANY 



1904 



