STUDIES IN EVOLUTION 



MAINLY REPRINTS OF OCCASIONAL J PAPERS^ ' 

 SELECTED FROM THE 



PUBLICATIONS OF THE LABORATORY OF INVERTEBRATE 



PALEONTOLOGY, PEABODY MUSEUM 



YALE UNIVERSITY 



BY 



CHARLES EMERSON BEECHER 



NEW YORK: CHARLES SCRIBNER'S SONS 



LONDON: EDWARD ARNOLD 



1901 



