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. 



Editoeiai, Committee : S. Newcomb, Mathematics ; E. S. Woodwaed, Mechanics ; E. C. Pickeeing, 



Astronomy ; T. C. Mendenhall, Physics ; E. H. Thurston, Engineering ; Ira Remsen, Chemistry ; 



Charles D. Walcott, Geology ; "W. M. Davis, Physiography ; Henry F. Osborn, Paleontology ; 



W. K. Brooks, C. Hart Merriam, Zoology ; S. H. Scuddee, Entomology ; C. E. Bessey, 



N. L. Britton, Botany ; C. S. Minot, Embryology, Histology ; H. P. Bowditch, 



Physiology ; J. S. Billings, Hygiene ; William H. Welch, Pathology ; 



J. McKeen Cattell, Psychology ; J. W. Powell, Anthropology. 



NEW SERIES. VOLUME XIV. 

 JULY -DECEMBER, 1901. 



NEW YORK 



THE MACMILLAN COMPANY 



1901 



/^^, 



